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CHEMISTRYin Sri Lanka

The Tri Annual Publication of the Institute of Chemistry Ceylon

May 2019 Volume 36 No. 02

Commemoration of the Fourth Death Anniversary of Emeritus Professor J N O Fernando

The fourth death anniversary of the late Professor J N O Fernando was commemorated on 7th and 8th March 2019. A “Pahan Pujawa” organized by the Student Council 2018/19 was held on 7th March 2019 while the morning alms were presented to monks the next day, alongside a multi-religious ceremony in the afternoon. The fourth commemoration oration on “Development of 21st Century Skills through STEM Education” was delivered by Professor G Bandarage on 8th March. The autobiography of the late Professor J N O Fernando “Recapturing an Epitome”, was launched as a project of the Alumni Association of the College of Chemical Sciences. Mrs Mandrupa Fernando, former colleagues of Professor Fernando, staff members and students participated to pay tribute to the late Professor.

Soorya Mangallaya 2019The Institute of Chemistry Ceylon held its annual Aurudu cerebrations on 7th April 2019, Sunday at the Presidents College, Kotte premises. The event was organized by the Student Council of 2018/19.

Mrs Mandrupa FernandoMrs Mandrupa FernandoProfessor G BandarageProfessor G Bandarage

Section of partcipantsSection of partcipants

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Chemistry in Sri Lanka ISSN 1012 - 8999

The Tri-Annual Publication of the Institute of Chemistry CeylonFounded in 1971, Incorporated by Act of Parliament No. 15 of 1972

Successor to the Chemical Society of Ceylon, founded on 25th January 1941

Vol. 36 No. 2 May 2019

Pages

Council 2018/2019 02

Outline of our Institute 02

Chemistry in Sri Lanka 02

Guest Editorial 03

Forty Eighth Annual Sessions and Seventy Eighth Anniversary Celebrations 2019 04

Technical Sessions 05

Chandrasena Memorial Award 09

Abstract of the Chandrasena Memorial Award 09

Abstracts of Research Papers to be presented at the 48th Annual Sessions 2019 10

Fifteenth Convocation of the College of Chemical Sciences 40

Convocation Address 41

36th Batch of Graduate Chemists 2018 43

Fifteenth Convocation Award List 2018 44

44th Batch of DLTC Diplomates 45

Tenth Inaugural Professorial Lecture 47

Chemistry Olympiad Sri Lanka 2019 48

All Island Inter School Chemistry Quiz Contest 2019 48

Graduateship Examinations in Chemistry 2018

Leve1 1 - Overall Award List 49



Entrance Scholarships & Bursaries 2019 50

Publications of the Institute of Chemistry Ceylon 51

RSC (SL Section) News 52

Theme for the year - Steering Chemical Industries towards a Smarter Nation

Adamantane House, 341/22, Kotte Road, Welikada, Rajagiriya Office ( : 2861231, 2861653, 4015230 Ê : 2861231, 2861653 E mail : [email protected] web page : www.ichemc.edu.lk

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The Tri-Annual Publication of the Institute of Chemistry Ceylon

Outline of our InstituteThe Institute of Chemistry Ceylon is a professional body and a learned society founded in 1971 and incorporated by act of Parliament No. 15 of 1972. It is the successor to the Chemical Society of Ceylon which was founded in 1941. Over 50 years of existence in Sri Lanka makes it the oldest scientific body in the country.

The Institute has been established for the general advancement of the science and practice of Chemistry and for the enhancement of the status of the profession of Chemistry in Sri Lanka. The Institute represents all branches of the profession and its membership is accepted by the government of Sri Lanka (by establishment circular 234 of 9-3-77) for purposes of recruitment and promotion of chemists.

Corporate MembershipFull membership is referred to as corporate membership and consists of two grades: Fellow (F.I.Chem.C.) and Member (M.I.Chem.C.)

Application for non-corporate membership is entertained for four grades: Associate (former Graduate) (A.I.Chem.C.), Licenciate (L.I.Chem.C.), Technician (Tech.I.Chem.C.) and Affiliate Member.

Revision of Membership Regulation All Special Degree Chemists can now apply directly to obtain Associate (Graduate) Membership. Three year B. Sc. Graduates (with an acceptable standard of Chemistry) can(i) directly become Licentiate (ii) obtain corporate membership in a lesser number of years.

Tech.I.Chem.C.Those who have passed the DLTC examination or LTCC examination or have obtained equivalent qualification and are engaged in the practice of Chemistry (or chemical sciences) acceptable to the Council are entitled to the designation Tech.I.Chem.C.Members/Fellows with Membership for Life are entitled to the designation of Chartered Chemist (C.Chem.) on establishment of a high level of competence and professionalism in the practice of chemistry and showing their commitment to maintain their expertise.

All corporate members (Members / Fellows) are entitled to vote and become Council/ Committee members whether Chartered Chemists or not.

Membership ApplicationsAny application for admission to the appropriate class of membership or for transfer should be made on the prescribed form available from the Institute Office.

Current Subscription RatesFees should be payed on 1st of July every year and will be in respect of the year commencing from 1st July to 30th June

Fellow Rs. 2000 Member Rs. 2000 Associate Rs. 1500 Licenciate Rs. 1200 Technician Rs. 750 Affiliate Rs. 1200 Membership for Life Rs. 15000

Entrance Fee All the grades Rs. 1000 Processing Fees* Rs. 500 Processing Fee for Chartered Chemist designation Rs. 5000 Institutional Members Rs. 2500 *per application for admission/transfer to any grade Headquarters BuildingAdamantane House341/22, Kotte Road, Welikada, Rajagiriya Telephone/Fax : 2861653, 2861231 Telephone: 4015230 e-mail : [email protected] web : www.ichemc.edu.lk

Council 2018/2019President : Prof. Sudantha LiyanagePresident Elect : Prof. (Mrs)P A ParanagamaVice President : Prof. (Mrs) S EkanayakeImmediate Past President : Dr. Poshitha Premarathne Hony. Joint Secretaries : Dr. (Mrs) C Padumadasa Dr. (Ms) H I C de SilvaHony. Treasurer : Dr. A A P KeerthiHony. Asst. Treasurer : Dr. S R GunathilakeHony. Editor : Dr. (Mrs) Theshini PereraHony. Asst. Editor : Dr. (Mrs) D N UdukalaSecretary for International Relations : Prof. (Mrs) J A LiyanageChairman/Academic Board : Prof. (Mrs) Sujatha Hewage Hony. Secretary for Educational Affairs : Dr. (Mrs) T Gobika Chairman, Admission & Ethical Practices Committee : Mr. E G SomapalaSecretary, A & EP Committee : Mrs. Deepika SenevirathneChairman, Board of Trustees : Prof. S P Deraniyagala

Elected MembersProf. (Ms) R D Wijesekera Dr (Mrs) L S R ArambewelaProf. P A N Punyasiri Prof. Siromi SamarasingheDr. Gamini Rajanayake Ms. P M Jayasinha Mrs. Kumudini Gunathilake Mr. N M S Hettigedara Mr. K R Dayananda Ms. Nalini De Silva

Editorial and Publicity Committee Dr. (Mrs) Theshini Perera (Editor) Dr. (Mrs) D N Udukala (Asst. Editor)Dr. (Mrs) T GobikaDr. Upul Kumarasinghe Mr. N I N S NadarasaMr. Sahan Jayasingha

CHEMISTRY IN SRI LANKA Chemistry in Sri Lanka is a tri-annual publication of the Institute of Chemistry Ceylon and is published in January, May and September of each year. It is circulated among the members of the Institute of Chemistry and students of the Graduateship/DLTC course and libraries. The publication has a wide circulation and more than 750 copies are published. Award winning lectures, abstracts of communications to be presented at the annual sessions, review papers, activities of the institute, membership news are some of the items included in the magazine. The editor invites from the membership the following items for publication in the next issue of the Chemistry in Sri Lanka which is due to be released in September 2019.• Personal news of the members• Brief articles of topical interests• Forthcoming conferences, seminars and workshops• Latest text books and monographs of interest to

chemists

All publications will be subjected to approval of the ‘Editorial and Publicity Committee’ and the Council of the Institute of Chemistry Ceylon. Further, prospective career opportunities for chemists, could be advertised in Chemistry in Sri Lanka at a nominal payment. The editor welcomes suggestions from the members for improvement of the publication.

Vol. 36 No. 2, May 2019

Chemistry in Sri Lanka

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Guest EditorialResearch and Innovation: Essential Components for Economic Prosperity

Professor Rohini M de SilvaDepartment of Chemistry, University of Colombo, Sri Lanka

The total number of global mobile phone users in 2019 will reach 4.68 billion compared to 750 million users in year 2000 and this is believed to surpass the number of people in the world in the near future. Over 2.6 million airline passengers

take flight with 43,000 airplanes having complex airspace systems compared to 1.8 million airline passengers in 2009. These are just examples of how the scale of things is being changed with time and its impact on social and business life over a period. During the next twenty years there will be more exponential changes in social life and on the economy than in the previous twenty years. If we look back carefully, we can see that this revolution is due to a blend of chemistry and physics through engineering. Therefore, the prime need for a better life can be directly correlated to research and innovation. The health of people has been improved tremendously by having countless new drugs and health products. New and improved transport and digital services offer many more comfortable life style options creating new jobs and bringing economic growth in addition to creating an informed society. Therefore, economic growth and standard of living of a country are well connected. Power of innovation is a determining factor for a country’s economic growth. Research and innovation should go hand-in-hand; research is an essential factor to guide numerous ideas into innovations. At the same time, one cannot deny the importance of pure or basic research, because all good innovations arise by assembling pieces of knowledge gained through such research work. Creating a society to inculcate more innovative ideas is of paramount importance for a country’s economic growth. Therefore, the foundation for innovations should come from the kindergarten. The children should be allowed to raise questions by observing their surroundings, rather than keeping children indoor and feeding them with theories. According to research, students who score lower in intelligence tests, end up doing better in exams because they compensate their lack of inborn intelligence with hard work. However, it is very important to inculcate creativity within a child because this is a unique human quality that will set future graduates apart from the

ever growing artificial intelligence. In order to focus on stimulating creativity, it is important to integrate science, technology, engineering and mathematics (STEM) into their curriculum. It is very important to design a thinking component in the curriculum in order to develop students’ ability to think by themselves and brain storm ideas to be implemented. Introduction of project-based learning will be one such path for building innovative ideas. The consequence of this will definitely lead to already well-trained students to undertake challenging research in future. Currently, more research funds are available for applied research rather than fundamental research due to various reasonable reasons. When it comes to applied research it is very important to understand the research problem that you are trying to solve and also it should be relevant to a considerable percentage of the society. The research ideas are usually connected to many unsolved issues in the world and many more can be gathered by having frequent discussions with the industrial sector. On the other hand, many problems seen in society or in industries cannot be solved by sticking to one discipline and as a result many successful stories on innovations are the product of interdisciplinary research. Definition of interdisciplinary research can be quoted as "Interdisciplinary research is a mode of research by teams or individuals that integrates information, data, techniques, tools, perspectives, concepts, and/or theories from two or more disciplines or bodies of specialized knowledge to advance fundamental understanding or to solve problems whose solutions are beyond the scope of a single discipline or area of research practice." The other significance of interdisciplinary research is that the teamwork among many disciplines ensures the exchange of experiences and development of knowledge between various parties and accumulation of more and more innovative ideas. This will provide a platform for each and every scientist to enter the research paradigm. The best innovations are yet to happen and it can be from anywhere in the world. The technologies such as Artificial Intelligence, Robotics, Biotechnology, Nanotechnology and Internet of Things (IOT) will shape up the planet in the next two decades and therefore it is paramount to understand this trend and implement policies to adopt various techniques to inculcate innovative minds in our school children and in university graduates.

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INSTITUTE OF CHEMISTRY CEYLONForty Eighth Annual Sessions and

Seventy Eighth Anniversary Celebrations 2019Inauguration of the 48th Annual Sessions, Institute of Chemistry Ceylon

Monday, June 10th 2019At Sri Lanka Foundation (SLF), Colombo 07

Programme

8.30 am Arrival of Guests

9.00 am Ceremonial Procession of the Council Members and Past Presidents

9.10 am Lighting of the Oil Lamp & National Anthem

9.15 am Welcome Address Prof Sudantha Liyanage President, Institute of Chemistry Ceylon

9.20 am Presidential Address

9.40 am Address by the Chief Guest Mr Navin Adikarama Chairman, Industrial Development Board

10.10 am Presentation of Awards, Prizes and Certificates Institute of Chemistry Ceylon Awards

• Yeoman Service Award – Professor Srianthie A Deraniyagala• Chandrasena Memorial Award – Dr Pamoda B Ratnaweera• Special Service Award – Mr D I S H Jayasingha• All Island Interschool Chemistry Quiz prizes• National Chemistry Olympiad Prizes

Graduateship Examination in Chemistry • Scholarships, Prizes and Awards • J N Oleap Fernando Memorial Scholarships

11.00 am Chandrasena Memorial Award Lecture Dr Pamoda B Ratnaweera Senior Lecturer, Department of Science and Technology, Uwa Wellassa University

11.30 am Vote of Thanks Prof Priyani Paranagama President Elect, Institute of Chemistry Ceylon

11.40 am Close of Ceremony

12.00 noon Annual General Meeting – 2019 (for Corporate Members only)

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Chief Guest at the 48th Annual SessionsMr Navin Adikarama

Mr Navin Adikarama is a strategic leader, a proven visionary, a successful entrepreneur, seasoned Telecommunication Technology and Management executive with exposure in Fortune -500 companies, mutli-national, multi-cultural, multi-ethnicity environments in Sri Lanka and across the globe including USA, UK, Singapore, China and Nepal. He has over twenty one years of extensive experience and proven track record in Corporate Management, both locally and internationally. Mr Adikarama obtained his Bachelor of Science, in Computer Science and Mathematics in 1996 from the Central Missouri State University, USA. He commenced his career while reading for his Bachelor of Science degree. He worked as a Computer Consultant at Central Missouri State University

from March 1994 to April 1996. Immediately after graduation in 1996, he joined the Information Resources, Inc., Fairfield, NJ USA as an Associate Project Director. Thereafter, he joined DMS Software Technologies (Pvt.) Ltd., Sri Lanka as a System Engineer in 1997. In 1998, Mr. Adikarama moved on to Millennium IT Pvt Ltd Sri Lanka as Senior Analyst – Systems. He has held several positions in acclaimed companies such as Convergys Singapore (Pvt) Ltd Sri Lanka and Asia Info International (Pte.) Ltd., Singapore. He has served as Chief Executive Officer and Director of Galoya Plantation (Pvt.) Ltd., Sri Lanka from 2007 to 2015. Mr. Adikarama has converted a loss-making Lanka Sugar Company to a profit making company within ten months. He initiated and completed the first private Water Purchase Agreement with the government of Sri Lanka. Furthermore, he restructured the Hingurana Sugar Industries as Gal-Oya Plantations. He successfully completed the Geneva Billing System at Sri Lanka Telecom. He is an academic Council Member of the South Eastern University of Sri Lanka. Mr. Adikarama has received two awards for extraordinary work on the Warner Lambert Account and for designing and implementing a program used by Decision Support Team. Mr Adikarama is presently the Chairman of the Industrial Development Board of Ceylon.

Professor Srianthie A Deraniyagala will be awarded the Yeoman Service Award at the 48th Annual Sessions in recognition of the yeoman services rendered in an honorary capacity and thereby richly contributing to the educational programmes of the Institute and the College in an exemplary and noteworthy manner. Prof Srianthie A Deraniyagala is a Senior Professor of the Department of Chemistry, University of Colombo and is credited with an illustrious academic career spanning over four decades.

Mr Sahan H Jayasingha will be presented with the Special Service Award at the 48th Annual Sessions in appreciation of over 16 years of devoted and loyal service to the Institute of Chemistry Ceylon. Mr. Jayasingha currently serves as the Publications Officer of the Institute in which capacity he continues to discharge his duties with great responsibility, dedication and to the entire satisfaction of the Institute.

YEOMAN SERVICE AWARD 2019

SPECIAL SERVICE AWARD 2019

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Technical SessionsVenue: P P G L Siriwardene Auditorium, Adamantane House, Rajagiriya

Time: 3.30 pm – 5.10 pm Date: 10th June 2019

Presentations by Prof. M. U. S. Sultanbawa Award Applicants

Session Chair: Professor Hema Pathirana

Panel members: Prof Hema Pathirana, Prof Sagarika Ekanayake, Prof Dhammike Dissanayake, Prof Janitha Liyanage, Dr Lakshmi Arambewela

Time Title Authors

3.30 - 3.50 pm

Estimation of dissolved organic carbon in source and treated water to ascertain treatment efficiency and water safety with respect to trihalomethanes

D Ilangangedara, A N Navaratne

3.50 – 4.10 pmSynthesis and evaluation of a transition metal ion-selective fluorescence sensor

M K B K Perera, S M Vithanarachchi, R D Wijesekera

4.10 - 4.30 pm

Synthesis and characterization of sulfonamide derivatized di-(2-picolyl)amine ligands and their rhenium tricarbonyl complexes towards fluorescent imaging

T Darshani, I C Perera, N T Perera

4.30 - 4.50 pmA novel immunoanalytical method for obesity biomarker detection using antibody function-alized silver nanoparticles

A A D T Abeysinghe, N M S Sirimuthu, P P R Perera

4.50 - 5.10 pm

Acute and subacute toxicity studies of the ethyl acetate soluble proanthocyanidins of immature inflorescence of Cocos nucifera L. in Wistar rats

C P Ekanayake, M G Thammitiyagodage, S Padumadasa, B Seneviratne, C Padumadasa, A M Abeysekera

REFRESHMENTS

Technical SessionsVenue: P P G L Siriwardene Auditorium, Adamantane House, Rajagiriya

Time: 8.30 am – 5.00 pm Date: 11th June 2019

SESSION 01

Chair: Professor Priyani A Paranagama

Time Title Authors

8.30 – 8.45 amEnhancement of crop productivity of red onion using tea waste biochar as a soil amendment

C Peiris, P D Wathudura, O Nayanathara, J J Wewalwela, M N Kaumal, B Gajanayake, S R Gunatilake

8.45 – 9.00 am

Development of a new spectrophotometric method for the analysis of metformin hydrochloride in drugs administered to patients with type II diabates

H M M B Herath, U K Jayasundara

9.00 – 9.15 amMethod development and validation of lipid lowering drug Atorvastatin using UV-Visible spectroscopy

P V N Kaushalya, Udaya K Jayasundara

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9.15 – 9.30 amApplication of green synthesized palladium nanoparticles using banana leaf extract in Suzuki cross-coupling reaction

S O A Dantanarayana, H I C De Silva

9.30 – 9.45 amMicrowave assisted acetylation of cellulose isolated from the banana pseudo-stem

K H C S Kariyawasam, M D M S Gunathilake, H I C De Silva, D T U Abeytunga

9.45 – 10.00 amSynthesis and characterization of novel zinc ditriazine complexes

W G K Fonseka, S P Deraniyagala, N T Perera

10.00 – 10.15 amA preliminary study on green synthesis of silver nanoparticles using Annona glabra leaf extract

W S Sithara, S Wickramarachchi, C R De Silva, A A A U Aberathna, L D Amarasinghe

10.15 – 10.30 am REFRESHMENTS

SESSION 2

Session Chair: Professor Janitha A Liyanage

Time Title Authors

10.30 – 10.45 amAdsorptive removal of Co(II) in aqueous solutions using Strychnos potatorum seed powder

K H Ranaweera, B A Perera

10.45 – 11.00 amCinnamon wood as an adsorbant for the removal of Cu2+ from aqueous solutions

D N Wijesekara, C S Udawatte

11.00 – 11.15 amSpectrophotometric determination of nitrite content in processed chicken products

W R P Somarathne, K K D Chilki, R M K P Jayatissa, S M S Nishadya, G V D Anuththara, I M S A Illangakoon, E G Somapala, C S Udawatte

11.15 – 11.30 amSorptive removal of p-nitroaniline from aqueous matrices by using acid modified tea-waste biochar

Y D Block, B Dissanayake, C Peiris, S R Gunatilake

11.30 – 11.45 amMicrowave and open vessel digestion methods for biochar and activated carbon

P D Wathudura, C Peiris, S R Gunatilake, M N Kaumal

11.45 – 12 noonDetermination of the oxalate ion concentration in green leafy vegetables

J V Liyanage, U K Jayasundara

12 noon – 1.00 pm REFRESHMENTS

SESSION 3

Session Chair: Professor Nimal Punyasiri

Time Title Authors

1.00 – 1.15 pmInfluence of volatiles from brinjal host on the attraction of brinjal fruit and shoot borer- Leucinodes orbonalis Guenee

M S F Nusra, P A Paranagama, L D Amarasinghe, D N Udukala

1.15 – 1.30 pm Determination of antioxidant activity, phenolic content and pH in wine prepared from local beet

S R Gunasekara, C S Udawatte, U S K Weliwegamage

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1.30 – 1.45 pm

Determination of microbiological and chemical parameters of ready-to-serve fruit drinks and carbonated beverages commercially available in Sri Lanka

F I Radiyya, E G Somapala, M Perera, S P Deraniyagala

1.45 – 2.00 pmChemical and microbiological contaminants and preservatives in commercially available tomato sauces

F N Iqbal, E G Somapala, M Perera, S P Deraniyagala

2.00 – 2.15 pmPlumbagin functionalized silver nanoparticles for potential antimicrobial applications

I N Dammulla, L B A E Bogahawatta, C P Gunasekara, M M Weerasekera, C Padumadasa, N M S Sirimuthu

2.15 – 2.45 pmCytotoxic potential and apoptotic effect of Barringtonia asiatica seed kernel against HepG2 cell line

R Paramasamy, S Ekanayake, S R Samarakoon

2.45 – 3.00 pmDurian and rambutan peels as potential sources of antioxidants

A A G Silva, S Wickramaarachchi, R N Attanayake, C S K Rajapakse

3.00 – 3.15 pm REFRESHMENTS

SESSION 4

Session Chair: Professor Sujatha Hewage

Time Title Authors

3.15 – 3.30 pmComplexation between Fe2+ and 1, 10 - phenanthrolin-5-amine and the quenching mechanism

G I P Wijesekera, M D P De Costa, R Senthilnithy

3.30 – 3.45 pmA study on the use of Bathophenanthroline as a fluorescence sensor for iron (II)

P P P Perera, M D P De Costa, R Senthilnithy

3.45 – 4.00 pmDFT study on classical Koshland retention mechanism of linamarin hydrolysis

D L S Dinuka, C N Ratnaweera

4.00 – 4.15 pmFabrication and characterization of water stable multi-layer graphene oxide membranes by potassium ion crosslinking

W R N M Bandara, J A Liyanage, A R Kumarasinghe

4.15 – 4.30 pmSynthesis and characterization of graphene oxide coated silica nanoparticles

M A S N Weerasinghe, J A Liyanage, A R Kumarasinghe

4.30 – 4.45 pmBinding interactions of coumarin derivatives with Hodgkin’s disease related protein ADAM-10; an in-silico approach

N M H N Thilakarathne, C N Ratnaweera, C S Udawatte

4.45 – 5.00 pm

A computational study on the inhibition of MCL-1 anti-apoptotic protein to activate apoptosis in cancer cells via commercially available natural product derivatives

M S V Costa, C S Udawatte, C N Ratnaweera

5.00 – 5.30 pm REFRESHMENTS

Cover PageThe cover page photograph (source: vevra) shows the Graduate Chemists at the 15th Convocation of the College of Chemical Sciences, Institute of Chemistry Ceylon, held at BMICH on 25th February 2019. This was the 36th batch and 149 students were formally awarded Graduate Chemist status, thereby increasing the overall production to a total of 1552. More formal photographs of the Convocation are on page 40.

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Chandrasena Memorial AwardAwarded for an exceptional research contribution of an original nature in the field of Organic Chemistry and/or related areas such as Biochemistry, Pharmacognosy, Molecular Biology and Bioactivity studies.

Abstract of Chandrasena Memorial Award - 2019

Novel and interesting antibiotic scaffolds from endophytic fungi of Sri Lankan origin

Pamoda B RatnaweeraDepartment of Science and Technology, Faculty of Applied Sciences, Uva Wellassa University, Badulla, Sri Lanka

Email: [email protected]

Antibiotic resistance within a wide range of infectious agents is increasing steadily, causing a growing public health crisis in the world. The development of resistance by pathogens limits the useful lifespan of antibiotics, causing an urgent need for introduction of new compounds. The most appropriate method to address the antibiotic resistance of bacteria is to find new alternatives to the currently available broad spectrum antibiotics through exploitation of nature. Endophytic fungi are an innovative group of organisms that can produce a plethora of secondary metabolites that feature unique structural characteristics and fascinating biological activities. Endophytic fungi in plants from distinct environmental settings and/or with unconventional biology, are considered to be a promising source for isolating novel secondary metabolites. Hence, in the current investigation to find novel antibiotic scaffold, endophytic fungi from various plants from different ecological settings in Sri Lanka were isolated, screened, the major bioactive secondary metabolites were purified using bioassay guided chromatographic techniques, characterized using NMR and mass spectral data and bio activities were evaluated. In the case of completely novel structures, confirmation of correct structural/stereochemical assignments was acquired by X-ray crystallography, and semi-synthetic modifications while biogenesis pathway was investigated through stable isotope feeding experiments. The novel antibiotic solanioic acid with an unprecedented carbon skeleton was isolated from Rhizoctonia solani from the medicinal weed, Cyperus rotundus, “common sedge” in Sri Lanka. Solanioic acid showed promising in vitro activity against the problematic human pathogen Methicillin resistant Staphylococcus aureus (MRSA, MIC: 1 µgmL-1). The culture feeding experiment with [1-13C]-acetate, [2-13C]-acetate and [1,2-13C]-acetate showed that the

steroid ring B contraction involved in the biogenesis of the unprecedented carbon skeleton of the solanioic acid involves cleavage of the C-5/C-6 bond. The feeding study also revealed that 9-epi-solanioic acid which spontaneously coverts to solanioic acid, is also produced by the R. solani cultures and it may be the actual natural product. Three novel thiodiketopiperazine derivatives, rostratazine A-C were isolated with two known compounds, exserohilone and boydine A, from the endophyte Setosphaeria rostrate from Costus speciosus in Sri Lanka. Rostratazine B showed porcine pancreatic alpha amylase inhibitory activity while exserohilone showed alpha-glucosidase inhibitory activity. The antibacterial compounds helvolic acid, equisetin, butyrolactone I, 9-epi viridol, gliotoxin and bisdethiobis(methylthio)gliotoxin, mycoleptodiscin B and chaetoglobosin A and C were isolated from endophytic Xylaria sp., Fusarium sp., Aspergillus terreus, Trichoderma virens, Hypocrea virens, Mycoleptodiscus sp., Chaetomium globosum species from Anoectochilus setaceus, Opuntia dillenii, Cyperus bulbosus, C. melanosperrmus, Premna serratifolia, Calamus thwaiesii and Nympaea nouchali plants respectively collected from different ecological settings in Sri Lanka. Although these are previously known compounds, in some instances the fungal source was new while the isolation of endophytic fungi from the host organisms and report of their antimicrobial activities turn out to be novel reports with some ecological implications. The investigations revealed that endophytic fungi from different, harsh and competitive environment settings are capable of producing a variety of bioactive compounds which may lead to the discovery of novel antibacterial chemical scaffold.

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Abstracts of Research Papers to be presented at the 48th Annual Sessions 2019

Technical Sessions : A - 01

Estimation of dissolved organic carbon in source and treated water to ascer-tain treatment efficiency and water safety with respect to trihalomethanes

D Ilangangedara1*, A N Navaratne2

1National Water Supply and Drainage Board, Sri Lanka2Faculty of Science, University of Peradeniya, Sri Lanka

*Email: [email protected]

The use of chlorine as a disinfectant, although essential for pathogen control, leads to the halogenation of organic matter present in source water and produces trihalomethanes (THMs) and halo acetic acids1 which have been identified as mutagenic and carcinogenic agents.2 For this reason, the United States Environmental Protection Agency currently regulates THMs and halo acetic acids in drinking water.3 Therefore, it is necessary to optimise plant conditions to minimize dissolved organic carbon (DOC) content in drinking water. The objectives of this study are to find a reliable method to quantify the DOC in natural water sources, identify the characteristics of DOC in source and treated water with respect to potential of THM formation and water safety and to measure the efficiency of water treatment process, considering the removal of DOC from treated drinking water. To quantify the DOC in natural water sources, standard solutions of humic substances were prepared using the commercially available humic acid powder (Sigma Aldridge brand) and a graph was obtained by scanning the different standard samples, against a series of wave lengths from 190 to 1100 nm. Thereafter, the wavelength range was narrowed down (230 nm to 630 nm), as the absorbance at the other wavelengths did not provide considerable variations. The concentration of the organic matter in the sample can be estimated by comparison of the unknown with results obtained from the standard graph. To identify the characteristics of DOC in water with respect to THM formation and water safety, specific ultraviolet absorbance (SUVA) was calculated. In addition, graphs were constructed by scanning the raw water samples and treated water samples from the water treatment plants on the same day for comparison to check whether concentrations of DOC is decreased or increased during the water treatment process. This study reports on the development of a method to measure the concentration of DOC in water using

DR 5000 spectrophotometer by scanning the water samples against various wavelengths in the presence of standard DOC solutions. Once the concentration is estimated, SUVA can be used to evaluate the water safety with respect to THM formation. In a treatment plant, SUVA values of raw water and the treated water taken simultaneously can be used to assess the efficiency of the treatment process. According to the study, treated water SUVA values were generally lower than 2 L/mg-m. Therefore, as per the USEPA drinking water guidance on disinfection by-products, our potable water indicates a high fraction of hydrophilic non-humic matter with low UV absorbance, a low chlorine demand and low THM formation potential. Therefore, water can be assumed as safe with regard to formation of THM when chlorinated. However few water sources were contaminated with DOC, showing the highest value of 7.2 at Peradeniya University Water Treatment Plant where the Mahaweli River is the source of raw water. Furthermore, it can be concluded that water treatment plants operated by National Water Supply and Drainage Board at Kandy South Region are effective in DOC removal by the water treatment process.

KeywordsNatural Organic Matter (NOM), Dissolved Organic Matter (DOM), Trihalomethane (THM), Absorbance, Specific Ultra Violet Absorbance (SUVA)

AcknowledgementThe authors appreciate the corporation of National Water Supply and Drainage Board.

References1. Croue, J.P.; DeBroux , J.F.; Amy, G.L.; Aiken, G.R.;

Leenheer, J.A. 1999, Natural Organic matter – Structural characteristics and reactive properties. Formation and control of disinfection by products in drinking water; American Water Works Association.

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2. Krasner, S.W.; Weinberg, H.S.; Richardson, S.D.; Pastor S.J.; Chinn, R.; Sclimenti, M.J.; Onstad, G.D.; Thurston, A.D. 2006; Environmental Science and Technology; Vol. 40; N0. 23; pp 7175-7185.

3. United States Environmental Protection Agency (USEPA); 2009, Federal Register; June 29, 2009; Vol 74, No. 123.


Synthesis and evaluation of a transition metal ion- selective fluorescence sensor

M K B K Perera1,2, S M Vithanarachchi1*, R D Wijesekera1

1Faculty of Science, University of Colombo, Sri Lanka 2College of Chemical Sciences, Institute of Chemistry Ceylon, Rajagiriya, Sri Lanka


Heavy metals are a common pollutant of the environment. Some of these metals can be toxic and hence, developing methods to detect their presence is important. Fluorescent chemosensors are available for detection of these metal ions. However, some of them have limitations such as low sensitivity, variations in sensitivity at different pH, and low solubility in aqueous systems.1 A novel fluorescence probe (L) was synthesized by esterification of ferulic acid with 6-hydroxymethyl-pyridine-2-carboxylic acid methyl ester. The synthesized fluorescence probe 6-[3-(4-Hydroxy-3-methoxy-phenyl)-acryloyloxymethyl]-pyridine-2-carboxylic acid methyl ester (L), was purified with a yield of 35% and characterized using UV-visible, fluorescence, FTIR and 1H NMR spectroscopy. Fluorescence studies of L showed an emission at 342 nm when excited at the wavelength of 300 nm in acetonitrile/water (3:2) mixture at room temperature. The fluorescence profile of the ligand in the presence of various metal ions such as Mn(II), Fe(III), Co(II), Ni(II), Cu(II), Zn(II), Cd(II), Hg(I), Mg(II) and Pb(II) was studied at pH ~7. The two main group elements studied; Mg(II) and Pb(II), did not show any quenching of fluorescence. Significant quenching of fluorescence (15%, 21% and 85%) was observed for Ni(II), Co(II) and Cu(II), respectively. From the studied transition metal ions Cu(II) was selected for further studies because it showed the highest quenching demonstrating the selective interaction of Cu(II) with ligand coampared to the other metal ions. Study of the behavior of L and Cu-L complex at various pH (1, 3, 5, 7, 9, 12) indicated that quenching by Cu(II) was greater in the pH range 5-8. Copper (II) forms a 1:2 complex with the L as indicated by the fluorescence titration and the Job’s plot. The Stern-

Volmer plot indicated that at least two processes of quenching take place. At lower concentrations of Cu(II), a higher quenching rate is observed suggesting that the quenching process could be due to static quenching with the formation of a Cu(II)-L complex. At higher concentrations of Cu(II), a slower quenching rate is observed. This latter quenching could be due to a combination of both static and dynamic quenching. The tolerance limit in the presence of Zn(II) found as molar ratio of 2:1(Zn(II): Cu(II)) demonstrated that L is more selective towards Cu(II). The findings of this research suggest that the synthesized probe L has the potential to be used as an “on-off ” fluorescence probe to detect Cu(II) in environmental samples.

AcknowledgementFinancial assistance by University of Colombo research grant (AP/3/2/2016/SG/18)

References 1. Jung, H. S.; Kwon, P. S.; Lee, J. W.; Kim, J. I. I.; Hong,

C. S.; Kim, J. W.; Yan S.; Lee, J. Y.; Lee, J. H.; Joo, T. J. Am. Chem. Soc. 2009, 131 (5), 2008–2012.

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Synthesis and characterization of sulfonamide derivatized di-(2-picolyl)amine ligands and their rhenium tricarbonyl complexes

towards fluorescent imagingT Darshani1, I C Perera2, N T Perera1*

1Department of Chemistry, University of Sri Jayewardenepura, Sri Lanka 2Department of Zoology and Environment Science, University of Colombo, Sri Lanka


The synthesis and characterization of four novel compounds are reported in this study; N(SO2)(1-nap)dpa (L1), N(SO2)(2-nap)dpa (L2), fac-[Re(CO)3(N(SO2)(1-nap)dpa)]PF6 (C1), fac-[Re(CO)3(N(SO2)(2-nap)dpa)]PF6 (C2) to evaluate their application as imaging agents. The photophysical properties and bio applicability of the novel compounds as well as of two previously synthesized compounds; N(SO2Me2Nnap)dpa (L3) and fac-[Re(CO)3(N(SO2Me2Nnap)dpa)]PF6 (C3) are reported herein. All the compounds (Figure 1) were characterized by X-ray diffraction studies, 1H NMR, FT-IR, UV-Vis and fluorescence spectroscopies. X-ray crystallographic analyses of the ligands confirmed the formation of the expected sulfonamide appended di-(2-picolyl)amine based ligands. The two naphthalene derivatized ligands, L1 and L2, were crystalized in monoclinic form while the triclinic form was obtained for L3. Formation of C1, C2 and C3 complexes were confirmed by 1H NMR studies in DMSO-d6 in which the singlet peak in the spectra of the free ligands designated for the methylene protons (~4.7 ppm) appeared as two doublets (endo- and exo-CH) upon binding to the metal (Table 1). In the FTIR spectra of the ligands, peaks due to S-N stretching vibrations obtained at 918-995 cm-1 have shifted to lower wavenumbers in the spectra of the metal complexes. The peaks in the absorption spectra of the metal complexes have shifted significantly compared to the respective free ligands. The absorption spectra of C1 and C3 show a bathochromic shift while C2 shows a hypsochromic shift compared to

the respective free ligands. With the exception of C2, all other compounds displayed promising photophysical properties with intense fluorescence peaks (L1: 338 nm, L2: 343 nm, L3: 525 nm, C1: 335 nm and C3: 535 nm). Among them, fluorescence spectra of L2, L3 and C3 showed remarkably high intensities even at low compound concentrations of 0.01 mM. Fluorescence microscopy images generated on human lymphocytes incubated with the synthesized compounds showed excellent cellular uptake for L3 and C3. Hence, fluorescence was observed at low concentrations of the compounds. Cell viability was not affected at these concentrations. Furthermore, localization of C3 in cytoplasmic membrane and cell nucleus of lymphocytes could be observed. In conclusion, there is a great potential of utilizing L3 and C3 in bio imaging applications.

Figure 1. Synthetic route of metal complexes

H6/6’ H5/5’ H4/4’ H3/3’ CH2

N(SO2)(1-nap)dpa 8.32 7.14 7.55 7.10 4.70[Re(CO)3(N(SO2)(1-nap)dpa)]PF6 8.90 7.47 7.98 7.37 5.66, 4.52∆δ (ppm) of C1 (+) 0.58 (+) 0.33 (+) 0.43 (+) 0.27N(SO2)(2-nap)dpa 8.32 7.15 7.63 7.29 4.60[Re(CO)3(N(SO2)(2-nap)dpa)]PF6 8.89 7.47 8.00 7.46 5.67, 4.59∆δ (ppm) of C2 (+) 0.57 (+) 0.32 (+) 0.37 (+) 0.17

Table 1. Comparison of 1H NMR shifts of the synthesized compounds

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Keywords imaging agents, sulfonamide complexes, Rhenium tricarbonyl, di-(2-picolyl)amine ligands

Acknowledgement Financial assistance by University of Sri Jayewardenepura under the grants ASP/01/RE/SCI/2015/19 and ASP/01/RE/SCI/2018/38


A novel immunoanalytical method for obesity biomarker detectionusing antibody functionalized silver nanoparticles

A A D T Abeysinghe1, N M S Sirimuthu1*, P P R Perera2 1Department of Chemistry, University of Sri Jayewardenepura, Sri Lanka

2Department of Biochemistry, University of Sri Jayewardenepura, Sri Lanka *Email: [email protected]

Obesity is a serious health issue related with increased body fat content. Escalating numbers of patients have been reported worldwide throughout the recent past, associated with a high cost in the healthcare sector. Other than being a disease condition by itself, it also acts as a risk factor for many metabolic and cardiovascular diseases. There is no definitive treatment available and control of the disease is achieved via lifestyle modifications; hence, early detection of the risk to be obese is of paramount importance. Nevertheless, accurate diagnostic methods for obesity are not widely available in the current clinical setting due to the high cost and associated drawbacks. Utilization of ‘leptin’, which is an accurate indicator of body fat content, has gained the attention of researchers as a biomarker for obesity.1 Therefore, this study was conducted with the aim of developing a novel immunoassay for the detection of leptin; a biomarker for obesity. Leptin detect ion was done using an immunoanalytical method by surface functionalization of silver nanoparticles using anti-leptin antibodies.2 Silver nanoparticles were synthesized by reduction of silver nitrate using sodium borohydride. Prepared silver nanoparticles were characterized using UV-Vis spectroscopy, dynamic light scattering (DLS) and scanning electron microscopy (SEM). The SPR peak was found to have a λmax of 405 nm with a FWHM of 72 nm and the average particle size was recorded as 40 nm. Bovine serum albumin (BSA) was used to stabilize the synthesized silver nanoparticles sterically and the optimum BSA concentration required was found to be 10 µg/ml. Synthesized nanoparticles were surface functionalized using anti-leptin antibodies which specifically bind with leptin. These antibody-nanoparticle conjugates were characterized by a currently used immunoassay technique named Enzyme Linked Immunosorbent Assay (ELISA), UV-Vis spectroscopy

and SEM and corresponding data verified the successful functionalization. Optimum pH and antibody-nanoparticle ratio for this functionalization process were determined using ELISA and according to obtained results, pH 9.5 and 1:10 ratio were selected to be the best conditions. Detection principle of this novel assay was based on the immuno-aggregation of anti-leptin functionalized silver nanoparticles in the presence of leptin. Changes in surface plasmon resonance due to this leptin induced aggregation were manifested via UV-Vis spectroscopy and spectral changes in the absorption peak confirmed the leptin detection ability. This nanoparticle based detection system could be used as an intermediate detection step for qualitative analysis of samples as positive or negative for leptin. It could be further developed as a novel method to measure body fat content thereby allowing the early diagnosis of the risk towards obesity. This study gives insight to a promising alternative method to existing detection methods which are more expensive and time consuming.

Keywords Obesity, leptin, Silver nanoparticles, anti-leptin antibodies

References1. Shah, N. R.; Braverman, E. R., PLoS One 2012, 7

(4), 1–8. 2. Endo, T.; Yamamura, S.; Nagatani, N.; Morita, Y.;

Takamura, Y.; Tamiya, E., Sci. Technol. Adv. Mater, 2005, 6, 491–500.

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Acute and subacute toxicity studies of the ethyl acetate soluble proanthocyanidins of immature inflorescence of Cocos nucifera L.

in Wistar ratsC P Ekanayake 1, M G Thammitiyagodage2, S Padumadasa3, B Seneviratne4, C Padumadasa1*,

A M Abeysekera1

1Department of Chemistry and Centre for Plant Materials and Herbal Products Research, University of Sri Jayewardenepura, Sri Lanka.

2Animal Centre, Medical Research Institute, Colombo 08, Sri Lanka.3Department of Obstetrics and Gynaecology, University of Kelaniya, Sri Lanka.

4Department of Pathology, University of Sri Jayewardenepura, Sri Lanka.*Email: [email protected]

The coconut palm, Cocos nucifera L. is a member of the monocotyledonous family, Arecaceae and mainly grows in tropical coastal areas. Ayurvedic and traditional medical practitioners of Sri Lanka use the decoction of the immature inflorescence of Cocos nucifera L. (IC) variety aurantiaca for the treatment of menorrhagia. The extraction, purification, and characterization of ethyl acetate soluble proanthocyanidins (EASPA) of IC have previously been reported. Furthermore, the progestogenic effect of EASPA at the dose level of 3.5 mg/kg body weight in female rats has also been reported.1 This finding is very significant as progestogens are widely used in the treatment of menorrhagia in western medicine. Acute and subacute toxicity studies of EASPA of the IC carried out using female Wistar rats according to Organization for Economic Co-operation and Development (OECD) guidelines 4232 and 4073, respectively is reported herein. In the acute toxicity study, a single dose of EASPA (2000 mg/kg body weight) was orally administered to rats and monitored for 14 days. In the subacute toxicity study, rats were orally administered with EASPA daily for 28 days at doses of 1.75, 3.5, 7 and 14 mg/kg body weight and observed for 28 days. No rat in either the acute or subacute toxicity study exhibited mortality, signs of toxicity (changes in the skin, fur, eyes, mucus membranes, respiratory depression) and behavioral changes (salivation, diarrhea, sleep, coma, lethargy). Furthermore, these rats did not show any significant change in their mean body weight and food and water intake. There was no significant difference in haematological [red blood count (RBC), haemoglobin (Hb), mean corpuscular volume (MCV), mean corpuscular haemoglobin (MCH), mean corpuscular haemoglobin concentration (MCHC), platelet count, white blood count (WBC), lymphocyte, monocyte, basophil and neutrophil] and biochemical (alkaline

phosphatase (ALP), alanine aminotransferase (ALT), urea, glucose and cholesterol) parameters of blood samples in treated rats of both toxicity studies with compared to control rats. Macroscopic examination of internal organs in rats of all test groups in both acute and subacute toxicity studies did not show any change in color and texture compared to the control group rats during necropsy. Histopathological examinations of internal organs of rats in all test groups in both toxicity studies showed a normal cellular architecture and were similar to those of the control group rats. Since there were no deaths or signs of toxicity in treated rats during the acute toxicity study, it is possible to suggest that the LD50 of EASPA is greater than 2000 mg/kg body weight via oral route. Observations made during the subacute toxicity study suggest that the long term intake (28 days) of EASPA at tested dose levels including the therapeutic dose do not induce any toxic effects in treated rats in comparison to control group rats. These results will be useful in the development of a novel therapeutic agent from EASPA of the IC for the treatment of menorrhagia, which incapacitates a considerable proportion of women worldwide.

KeywordsCocos nucifera L., progestogenic effect, acute toxicity, subacute toxicity

References1. Padumadasa, C.; Dharmadana, D.; Abeysekara,

A.M.; Thammitiyagoda, M.G., Int. J. Ayurveda Pharma Res. 2015, 3(7), 1-6.

2. Organization for Economic Co-operation and Development (OECD), The OECD Guideline for testing of chemicals: 423 Acute oral toxicity-acute toxic class method, OECD, Rome, 2001.

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3. Organization for Economic Co-Operation and Development (OECD), The OECD Guidelines for Testing of Chemicals, Repeated Dose 28-day Oral

Toxicity Study in Rodents :407, OECD, Paris, France, 1995.

Enhancement of crop productivity of red onion using tea-waste biochar as a soil amendment

C Peiris1,2, P D Wathudura1, O Nayanathara1, J J Wewalwela3, M N Kaumal2, B Gajanayake4, S R Gunatilake1

1College of Chemical Sciences, Institute of Chemistry Ceylon, Rajagiriya, Sri Lanka.2Department of Chemistry, University of Colombo, Sri Lanka.

3Department of Agricultural Technology, University of Colombo, Colombo, Sri Lanka4Department of Plantation Management, Wayamba University of Sri Lanka, Gonawila, Sri Lanka



Biochar (BC) is a low cost adsorbent produced by the pyrolysis of biomass which can be used for agricultural purposes. Tea waste is an excellent biomass for BC production since it is an abundant solid waste in Sri Lanka. The presented work was carried out to study the impact of BC as a soil amendment on the quality of Kalpitiya soil and the crop productivity within a time period of 3 months. Soil was collected from 3 different sites located at Kalpitiya during October for the greenhouse experiment where the particle size was ranged below 1 mm. Tea waste was slow pyrolyzed in a muffle furnace at 300, 500 and 700 °C. Column study at a flow rate of 2 – 3 mL/min was carried out to determine the direct effect by 500 °C BC. Although a significant direct effect was not observed by other nutrients, the direct contribution of potassium by BC was noteworthy. A volume of 1500 mL was used to minimize the amount of potassium that was directly released from BC. Microbial population for the control was 80 CFUs where it was increased by 41 and 33% for 2% amended nitric acid and sulfuric acid modified BC pots respectively. Highest plant growth parameters such as root length, leaf height and total fresh (wet) and dry weight were observed from 2% amended modified BC. The obtained biomass yield in the control was 33 g and a 30% increment was observed upon 2% nitric acid modified BC amended pots. In a comparison between 2% and 5% amendments, total fresh weight of 31 g was observed by 2% amended pots where the yield was as low as 12 g from 5% amended pots. Also, the control plants yielded a 33 g weight of biomass which was lowered up to 11 g with 5% amendments. Hence, it can be concluded that 2% amendment has favored the overall plant growth parameters where 5% amendment has slowed the growth rate. Overall, a clear growth can be seen in biomass yield and total fresh weight going

from two weeks to one month.

Keywords Tea-waste biochar, plant growth, microbial population, modified Biochar, direct effect

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Development of a new spectrophotometric method for the analysis of metformin hydrochloride in drugs administered to patients with type II diabetes

H M M B Herath, U K Jayasundara*College of Chemical Sciences, Institute of Chemistry Ceylon


Determination of drug concentration is important, as a specific dose is needed to be administered to each patient. This dose is different from one person to another person since the effective dose (ED50) for one person could be deadly for another person. Therefore, it is very important to ensure that the drug has the correct amount of active ingredients present in any drug component administered to a patient as overdosing or underdosing may create critical consequences to the patient. In a Sri Lankan context, most of the drugs are imported from different countries. Therefore, the quality of the drug as well as the active ingredient concentration might be different from the labeled value. Here we are presenting a simple and fast method to determine the active ingredient concentrations of metformin hydrochloride, a drug administered to patients with type II diabetes, using UV-Visible spectroscopy. The method has been developed and validated according to the International Conference on Harmonization (ICH) guidelines and standard acceptance criteria for parameters such as linearity, range, accuracy and precision, limit of detection (LOD), and limit of quantitation (LOQ), and stability. The scan of prepared standard stock solution of 100 ppm, showed that the λmax value occurs at 233 nm with de-ionized water as the blank. A five point calibration curve was obtained within a concentration range of 2 ppm to 10 ppm with a regression equation y= 0.0751x + 0.0075 and a correlation coefficient (R2) 0.9995. The accuracy analysis by spike recovery method at three levels (50%, 100%, and 150%) showed that the best mean recoveries occur from 92.14 % to 95.04% of the spiked drug. Furthermore, the developed method yielded the % Relative Standard Deviation (RSD) values for repeatability (1.98%) and intermediate precision (1.37%) which are accepted under 2% acceptance criteria of ICH. In addition, limit of detection (LOD) and limit of quantitation (LOQ) values for this study were 0.609 ppm and 1.845 ppm, respectively. Also, the developed analytical method can be used to determine the concentration of metformin hydrochloride in tablet formulations stored for 7 days under refrigerator conditions.

Test samples (8 brands) were purchased from local pharmacies located in the Colombo District and their labeled values of active ingredient was 500 mg. The developed method resulted that the actual concentration of the active ingredients ranged from 282.70 ± 2.76 to 454.19 ± 0.95 mg. The method demonstrated that test samples from Sri Lanka and Indonesia had significantly small amount of active ingredients per 500 mg tablet which causes underdosing. The test sample manufactured in Bangladesh had the highest amount of active ingredient component (454.19 mg) while the Indian brands had active ingredient ranged from 340.63 mg to 441.46 mg. The test sample from Pakistan had 419.28 mg of active ingredient per 500 mg tablet.

KeywordsMethod validation, ICH guidelines, Metformin hydrochloride, UV-vis Spectrophotometry, Sample analysis

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Method development and validation of lipid lowering drug Atorvastatin using UV-Visible spectroscopy

P V N Kaushalya, U K Jayasundara Institute of Chemistry Ceylon, College of Chemical Sciences, Rajagiriya


With the high risk for cardiovascular diseases, statin drugs have become the life saver for millions of people around the world. Atorvastatin Calcium is one of the most commonly used lipid lowering drugs. Since this drug has been extensively used, it is essential to know the exact active ingredient concentration as the dose itself might cause negative impact on the patients. Present study describes the development and validation of a simple, sensitive, specific and an economically viable UV-Visible spectroscopic method to evaluate the drug Atorvastatin Calcium in the tablet dosage form. In the current study, validation was performed according to Good Laboratory Practices (GLP) in accordance with the guidelines of the International Conference of Harmonization (ICH) using a secondary standard. To develop an acceptable analytical method, it was required to prepare a soluble form of the drug component. Initially water was used as the vehicle but it turned out that methanol:water (50:50) solvent system functions better due to high solubility and the stability. Using UV Visible spectrum it was found that the maximum absorbance of the drug was at 245 nm and calibration curves were prepared measuring absorption values at 245 nm for the standard samples. For the calibration curve a range of concentrations starting from 5 ppm to 15 ppm was prepared using a 100 ppm stock solution. The developed method obeyed the Beer’s law and the linear regression coefficient of the calibration plot was 0.998. The method was validated in terms of linearity, accuracy, range, precision, robustness, limit of detection (LOD), limit of quantification (LOQ) and stability. Precision studies were done under two main levels as repeatability and intermediate precision. For all the standard samples, it was discovered that the percentage relative standard deviation (%RSD) was less than 2% which was within the acceptance criteria. Recovery studies for the analysis revealed that the concentration range is 90-110% for all the prepared samples. The limit of detection of the drug Atorvastatin Calcium was found to be 0.909 ppm and limit of quantification was found to be 2.754 ppm. Stability studies carried out under two conditions, refrigerator

and room temperature for 14 days, showed that the drug component was stable for 14 days under room temperature without refrigerator conditions. Several market samples collected from suburbs of Colombo were also analyzed using the validated method and the concentrations of them were determined. The percentage label claim for the brands varied from 90.0 to 98.8. This shows that the method developed can be adapted to the routine method of estimating Atorvastatin Calcium in tablet dosage form.

KeywordsAtorvastatin Calcium, UV-Visible spectroscopic, GLP, ICH guidelines, validated, method developed

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Application of green synthesized palladium nanoparticles using banana leaf extract in Suzuki cross-coupling reaction

S O A Dantanarayana, H I C De Silva*Department of Chemistry, University of Colombo, Sri Lanka


Application of plant extract-based nanoparticles in organic synthesis has become an emerging field today due to its biocompatibility, eco-friendliness and cost efficiency.1,2 The objectives of the present study were to develop an elementary and ecological method to synthesize palladium nanoparticles (Pd NPs) using extracts of banana leaves, which is a commonly found agro-waste in Sri Lanka, and investigate the catalytic activity of the synthesized Pd NPs in Suzuki cross-coupling reactions. Pd NPs were synthesized by reacting an aqueous solution of PdCl2 (0.003 M) with banana leaf extract which was prepared by sonicating fresh banana leaves for 3 hours followed by boiling for 30 minutes in water. Synthesized Pd NPs were applied as the catalyst in Suzuki cross-coupling reaction between phenyl boronic acid and bromobenzene using K2CO3 as the base (Scheme 1). The reaction conditions; solvent (water, water/ethanol), temperature (40-90 ºC), reaction time (0.5-3 hours) were optimized. Catalyst reusability of synthesized Pd NPs in Suzuki cross-coupling reaction was assessed. Suzuki cross-coupling reactions were also carried out under microwave conditions (600 W, 80 ºC, 2-5 minutes) using the green synthesized NPs.

Scheme 1. Suzuki cross-coupling reaction of phenyl boronic acid and bromobenzene

The disappearance of the peak at 420 nm which corresponds to Pd2+ in the UV- Vis spectrum indicated the formation of Pd NPs. The size range of the nanoparticles obtained by SEM was between 90 – 400 nm. The optimum conditions for the Suzuki cross-coupling reaction of bromobenzene and phenyl boronic acid was determined to be 3.2 mg of Pd NPs (2% w/w relative to bromobenzene) synthesized using banana leaf extract, 80 ºC, 30 minutes in water-ethanol which afforded 95% yield. Reaction in water under the same

optimum conditions afforded 79% of biphenyl. When green synthesized Pd NPs were recycled and reused, the Suzuki cross-coupling reaction produced 64% yield up to five cycles when water was used as the solvent and 83% yield up to three cycles when water/ethanol mixture was used. Even though, it has been reported that green synthesized Pd NPs could catalyse the homocoupling of phenyl boronic acid to afford biphenyl,3 it was found that the yields obtained in this research were only due to the heterocoupling as homocoupling did not take place during 30 minutes. It was found that by carrying out the Suzuki cross-coupling reactions under microwave conditions in water/ethanol, the reaction time could be further reduced to 3 minutes at 600 W, which yielded biphenyl in 78%. It can be concluded that Pd NPs green synthesized using banana leaf extracts are catalytically active on Suzuki cross-coupling reaction. Furthermore, the synthesized Pd NPs could be used as a catalyst in Suzuki cross-coupling reactions between substituted aryl bromides and arylboronic esters.

KeywordsPalladium nanoparticles, banana leaf extract, Suzuki cross-coupling reaction

References1. Liu, G.; Bai, X. IET Nanobiotechnology 2017, 11 (3),

310–316.2. Quazi, F.; Hussain, Z.; Tahir, M. N. RSC Adv. 2016,

6 (65), 60277–60286.3. Adamo, C.; Amatore, C.; Ciofini, I.; Jutand, A.;

Lakmini, H. J. Am. Chem. Soc. 2006, 128 (21), 6829–6836.

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Microwave assisted acetylation of cellulose isolated from the banana pseudo-stem

K H C S Kariyawasam, M D M S Gunathilake, H I C De Silva*, D T U AbeytungaDepartment of Chemistry, University of Colombo, Sri Lanka


Cellulose acetate (CA) is an ester derivative of cellulose with a wide range of industrial applications as coatings, cigarette filters, textile fibers, filtration membranes, photo films, composites, and medical and pharmaceutical products.1 Annually, a few tons of banana pseudo-stems are left behind in the plantation soil as an agro waste in Sri Lanka. Therefore, this study was performed to develop efficient and environmentally friendly methods to isolate cellulose from the banana pseudo-stem (Pisang Awak-species ‘seeni kesel’), which is an agro waste in Sri Lanka, and to synthesize CA using the isolated cellulose. Cellulose was isolated using microwave (MW) irradiation in the dewaxing step and the % yield (W/W) was compared with that of the conventional method2 which involves dewaxing by Soxhlet extraction for six hours. The crystallinity index of the isolated cellulose was determined using X-ray Diffraction. CA was synthesized using the isolated cellulose in the presence of iodine as the catalyst1 and the reaction conditions (reaction temperature, MW power and reaction time) were optimized. The degree of substitution (DS) of CA was determined using a back titration method.3 Isolated cellulose and the CA were characterized by FT-IR spectroscopy. The % yield (W/W) of cellulose (19.7%) obtained using MW irradiation in the dewaxing step at optimum reaction conditions (300 W, 60 oC, 5 minutes) was higher than that of the conventional method (8.35%), indicating that the Soxhlet extraction in the dewaxing step can be successfully replaced with the MW irradiation. The FT-IR spectroscopic data summarized in Table 1 indicate that the cellulose isolation was successful.

The crystallinity index of the isolated cellulose was high (73%), indicating that the isolated cellulose is in high quality, high rigidity and thus, suitable for industrial applications. The best % yield (W/W) of CA synthesized using the cellulose isolated from the banana pseudo-stem was 97.8% with DS of 2.87 at the optimum reaction conditions (500 W, 50 oC for 25 minutes with 1.27 eq of iodine). The three characteristic peaks for CA at 1737 cm-1, 1368 cm-1 and 1236 cm-1 corresponding to C=O stretching of ester, C-H stretching in –O(C=O)-CH3 and C-O stretching of acetyl group, respectively indicate that the acetylation of the isolated cellulose was successful.The results obtained from this study indicate that CA can be successfully synthesized with a high yield using the cellulose isolated from the banana pseudo-stem in the presence of iodine as the catalyst. This CA synthesis makes the banana pseudo-stem which is an agro waste into a value-added product. The high percentage of crystallinity index of cellulose indicates an ordered and compact structure which results in high material strength and can be applied in improving the mechanical properties of composite materials.4 The use of MW irradiation makes the process more efficient by reducing the reaction time and environmentally friendly with lesser use of solvents. The successful use of an agro waste in Sri Lanka into industry makes the process more economical and environmental friendly.

Keywords cellulose, cellulose acetate, banana pseudo-stem, microwave irradiation, iodine catalyst.

Table 1: The comparison of the FT-IR spectroscopic data obtained for commercial cellulose and the isolated cellulose

Spectrum-OH

stretching/ (cm-1)

-C-H stretching/

(cm-1)

H-O-H bending of absorbed

water / (cm-1)

-C-O stretching/

(cm-1)

C-O-C pyranose ring skeletal

vibration/ (cm-1)

Commercial cellulose 3336 2900 1643 1160 1053

Isolated cellulose (Soxhlet extraction) 3338 2902 1635 1158 1053

Isolated cellulose (MW irradiation) 3335 2899 1644 1158 1056

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References1. Li, J.; Zhang, L. P.; Peng, F.; Bian, J.; Yuan, T. Q.; Xu,

F.; Sun, R. C. Molecules 2009, 14, 3551–3566.2. Nazir, M. S.; Wahjoedi, B. A.; Yussof, A. W.; Abdullah

M. A. BioResources 2013, 8, 2161–2172.3. Bushra, M.; Xu, X.; Pan, S. Starch 2013, 65, 236–243.4. Li, M.; Cheng, Y. L.; Fu, N.; Li, D.; Adhikari, B.;

Chen, X. D. Int. J. Food Eng. 2014, 10, 427–436.


Synthesis and characterization of novel zinc ditriazine complexes W G K Fonseka1, S P Deraniyagala2, N T Perera2*

1College of Chemical Sciences, Institute of Chemistry Ceylon, Rajagiriya, Sri Lanka. 2Department of Chemistry, University of Sri Jayawardenepura, Sri Lanka.


Triazine derivatives have gained considerable attention due to their biological properties. Here we have focused on the synthesis and spectroscopic characterization of novel Zinc complexes bearing derivatives of 1,2,4-Ditriazine ligands (R = Me, Et, Py). Although the ditriazine scaffold was synthesized more than five decades ago,1 only a few reports exist on their metal complexes2,3 and Zn(II) complexes of ditriazine are relatively unexplored. Three novel Zn(II) complexes [Zn(Me4dt)Cl2] (C1), [Zn(Et4dt)Cl2] (C2) and [Zn(Py4dt)Cl2] (C3) of three selected ditriazine derivatives [Me4dt= Bis-3,3’-(5,6-dimethyl-1,2,4-triazine) (L1), Et4dt= Bis-3,3’-(5,6-diethyl-1,2,4-triazine) (L2), Py4dt= Bis-3,3’-(5,6-dipyridyl-1,2,4-triazine) (L3)] were obtained by the reaction of ZnCl2 with each ligand (1:1). Since higher melting point is a characteristic feature of a metal complex, melting points of all three complexes were determined (C1: 182-184 °C, C2: 220-221 °C, C3: >300 °C) and found to be are much higher than that of the corresponding ligands (L1: 91-93 °C, L2: 118-120 °C, L3: 256-258 °C). These complexes were characterized by UV-visible, FT-IR and 1H NMR spectroscopy. In UV-visible spectra, two peaks were observed for the ligands (L1: 240 nm, 256 nm, L2: 240 nm, 257 nm, L3: 226 nm, 302 nm) vs. one for the corresponding complexes (C1: 236 nm, C2: 240 nm, C3: 297 nm). FTIR spectra of the complexes are different from those of the ligands and the wavenumber of C=N of the ligands decreased from 1674.08 υ / cm-1 (L1), 1527.51 υ / cm-1 (L2), 1581.51 υ / cm-1 (L3) to 1623.94 υ / cm-1 (C1), 1504.36 υ / cm-1 (C2), 1573.79 υ / cm-1 (C3), respectively confirming that nitrogen attributable to C=N is coordinated to zinc metal via lone pair donation. 1H NMR spectra recorded for above methyl and ethyl zinc(II) complexes do not show considerable shifts in comparison to their corresponding ligands and may be due to metal coordinating with the solvent. It is suggested

to record the 1H NMR again in non-coordinating solvent such as CD2Cl2. Surprisingly in the case of Py4dt, its corresponding zinc(II) complex showed large downfield thus providing proof that the metal complex has been formed.

Keywords1,2,4-ditriazine, Zn(II) ditriazine complexes, spectroscopy methods, melting points.

AcknowledgementFinancial assistance by University of Sri Jayewardenepura under the grant ASP/01/RE/SCI/2015/19

References 1. Jensen, R. E.; Pflaum, R. T., Anal. Chim. Acta 1965,

32 (C), 235–244.2. Chen, Y.; Zhou, X.; Wei, X. H.; Yu, B. Le; Chao,

H.; Ji, L. N., Inorg. Chem. Commun. 2010, 13 (9), 1018–1020.

3. Maheshwari, V.; Marzilli, P. A.; Marzilli, L. G., Inorg. Chem. 2008, 47 (20), 9303–9313.

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A preliminary study on green synthesis of silver nanoparticles using Annona glabra leaf extract

W S Sithara1, S Wickramarachchi 1*, C R De Silva2, A A A U Aberathna3, L D Amarasinghe3

1Department of Chemistry, University of Kelaniya, Sri Lanka 2Department of Chemistry and Physics, Western Carolina University, USA

3Department of Zoology and Environmental Management, University of Kelaniya, Sri Lanka*Email: [email protected]

In this study, an eco-friendly, simple, rapid and a cost effective biological method for reducing Ag+ ions into silver nanoparticles (AgNPs) using the leaf extract of Annona glabra (A. glabra) plant has been developed. Although a number of plant extract mediated synthesis of AgNPs have been reported in the literature no previous attempt has been made on the use of A. glabra in the green synthesis of AgNPs. For the synthesis of AgNPs, the plant extract was prepared by chopping the fresh leaves and allowing it to heat with deionized water (100 mL) at 70 oC for 1 hour. Then, the supernatant was separated by filtration. Finally a solution of aqueous silver AgNO3 was added in the ratios of leaf extract: AgNO3 1:10 v/v and it was incubated for 3 hours at room temperature for the formation of AgNPs. Three concentrations of AgNO3 (1, 5, and 10 mM) were tried. Phytochemicals present in the plant extract were identified. The formation of the AgNPs were confirmed by visual colour change of the solution and UV-Vis spectroscopy. Synthesized AgNPs were characterized by dynamic light scattering (DLS), scanning electron microscopy (SEM) and Fourier transform infrared spectroscopy (FTIR). The colour change from yellow to dark brown/black and the plasmon resonance band around 450 nm in the UV-Vis spectra indicated the formation of AgNPs. The size of the synthesized AgNPs ranged between 50-380 nm. SEM analysis showed that the synthesized AgNPs were spherical in shape and form clusters. Flavones, reducing sugars, phenols and proteins were present in the A. glabra leaf extract. In the biosynthesized process these compounds in the leaf extract acts as reducing agent for Ag+ and the stabilizing agent for AgNPs. FTIR data suggest the presence of functional groups; O−H stretching (3000-3660 cm-1), C=C stretching (1627 cm-1), C-H stretching of aldehydes (2850 cm-1), C-N stretching (1312 cm-1), sp3 C-H stretching (2929 cm-1) on AgNPs as capping and stabilizing agents. The presence of aldehyde groups was evident from the IR spectrum of the plant extract. The sugar aldehyde reduces the Ag+ into

metallic Ag0. This is followed by nucleation of metallic Ag into AgNPs. However, identifying the role of each biomolecule which is present in the leaf extract, is challenging. The successful formation of AgNPs using A. glabra leaf extract as the reducing agent is proven. Here we have introduced A. glabra as a novel plant source for the green synthesis of AgNPs. Further optimization of reagent and reaction conditions are needed to obtain a narrow particle distribution of AgNPs.

(a) (b)Figure 1: (a) Annona glabra leaf extract with AgNPs, (b) UV-Vis absorption spectra of AgNPs synthesized at different concentrations of AgNO3

KeywordsSilver nanoparticles, green synthesis, Annona glabra, leaf extract

AcknowledgementsThe laboratory and instrumental facilities provided by the Department of Chemistry, University of Kelaniya and University of Peradeniya are greatly acknowledged.

22



Adsorptive removal of Co(II) in aqueous solutions using Strychnos potatorum seed powder

K H Ranaweera , B A Perera*1Department of Chemistry, Faculty of Applied Sciences, University of Sri Jayewardenepura,

Gangodawila, Nugegoda, Sri Lanka.*Email:[email protected]

Contamination of natural water bodies due to improper discharge of heavy metals has become a worldwide environmental problem. Development of low cost adsorbent materials for the removal of heavy metals, utilizing the technique of adsorption is an effective solution to this problem. The present study explores the potential use of clearing nut seed powder (Strychnos potatorum) as an adsorbent for the removal of Co(II) from aqueous solutions. Batch adsorption studies were carried out by varying contact time, initial pH, initial Co(II) concentration, adsorbent dosage and temperature. An equilibrium adsorption capacity of 1.8619 mg/g was observed at an optimal pH of 5.0 for initial metal ion concentration of 20 ppm, 0.3 g/100.00 cm3 adsorbent dosage with 250-500 µm particle size, within the contact time of 120 minutes at 303 K. Adsorption isotherm experiments indicated both Langmuir and Freundlich isotherm models fit well to the experimental data with correlation coefficients greater than 0.98. The best isotherm model can be considered as Langmuir model with highest correlation coefficient and the maximum monolayer adsorption capacity obtained was 4.2452 mg/g. The adsorption kinetic data fitted well with pseudo second order kinetic model. The calculated thermodynamic parameters showed that adsorption process is spontaneous and exothermic in nature. The Gibbs free energy change in Co(II) adsorption process at 303 K was -20.580 kJ mol-1 while the enthalpy change was -23.04 kJ mol-1. The negative entropy change of -8.002 J mol-1 K-1 indicates the decrease in randomness of Co(II) at solid-liquid interface.1 The surface properties of the adsorbent were analyzed by FT-IR spectroscopy and SEM analysis. FT-IR analysis indicated the presence of hydroxyl, amide and C-O functional groups on the adsorbent and SEM analysis confirmed the presence of irregular surface structure with tiny pores on it, which is important for adsorption. The clearing nut seed powder obtained after surface modification by acid treatment showed a higher adsorption capacity of 2.8381 mg/g when compared with surface unmodified clearing nut seed powder. Therefore clearing nut seed powder

and surface modified clearing nut seed powder can be considered as potential adsorbents for the removal of Co(II) in aqueous solutions.

Keywords adsorption, isotherms, kinetics, Cobalt (II)

References1. Anbalagana, K.; Senthil Kumar, P.; Sangita, K. G.;

Karthikeyan, R., Desalination and Water Treatment 2013, 53, 171–182.

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Cinnamon wood as an adsorbant for the removal of Cu2+ from aqueous solutions

D N Wijesekara, C S Udawatte*Institute of Chemistry Ceylon, Rajagiriya, Sri Lanka


Heavy metal water pollution remains one of the most harmful ecological and health issues globally, and Cu2+ is a common pollutant found in water bodies. Cinnamon (Cinnamomum verum or Cinnamomum zeylanicum) is native to Sri Lanka. Cinnamon wood is discarded as firewood, making it an ideal candidate as a locally available low cost adsorbent for Cu2+. Cinnamon wood from Ratnapura was cut into small pieces, washed with distilled water and dried in sunlight. It was further dried in an oven at 100 oC for two hours and ground. The saw dust was in 2.0 mm, 1.7 mm, 0.6 mm, 0.5 mm and 0.15 mm particle size. A stock solution of 1000 ppm Cu2+ solution was prepared from CuCl2.2H2O and deionized water. Batch adsorption experiments were carried out to study the effect of contact time, particle size and optimum mass of adsorbent for the adsorption of Cu2+ onto cinnamon sawdust. All experiments were performed in duplicate, with 1000 ppm Cu2+ without cinnamon wood as the control. Particle size of cinnamon sawdust at which maximum adsorption takes place was investigated by incubating 1.0 g of cinnamon wood of particle size 0.15 mm, 0.50 mm, 0.60 mm, 1.70 mm and 2.00 mm with 25.00 mL 1000 ppm Cu2+ solution for 120 min in a shaker at 200 rpm. Optimum shaking time was determined by incubating 1.0 g of cinnamon wood saw dust of 2.00 mm particle size and 25.00 mL of 1000 ppm Cu2+ solution in 50.00 mL plastic tubes in a shaker for 30, 60, 90 and 120 minutes at 200 rpm. Optimum mass of adsorbent was determined by incubating 0.2 g, 0.4 g, 0.6 g, 0.8 g, and 1.0 g of 2.00 mm particle size cinnamon sawdust with 25.00 mL 1000 ppm Cu2+ solutions in 50.00 mL plastic tubes for 120 minutes at 200 rpm. After shaking, samples were filtered using Whatman No 14 filter paper and the residual copper in the aqueous solution was determined by Atomic Absorption Spectroscopy using a Hitachi ZA3000 AAS Spectrophotometer. Percentage removal of Cu (II) by sawdust and its binding capacity were calculated. According to this study, the removal efficiency for Cu (II) was highest when the contact time was 60 minutes. Highest removal of Cu (II) was observed when

the mass of adsorbent was 0.4 g per 25.00 mL of 1000 ppm Cu (II) solution, and cinnamon sawdust of particle size 0.6 mm. In optimum conditions, removal of Cu (II) was 16.4 mg/g of cinnamon sawdust (69.4%). The results obtained demonstrates the potential use of cinnamon wood as a low cost adsorbent of Cu(II) which can be used for treatment of industrial wastewater.

24



Spectrophotometric determination of nitrite content in processed chicken products

W R P Somarathne*, K K D Chilki, R M K P Jayatissa, S M S Nishadya, G V D Anuththara, I M S A Illangakoon, E G Somapala, C S Udawatte

College of Chemical Sciences, Institute of Chemistry Ceylon, Sri Lanka*Email: [email protected]

Nitrites are used as preservatives in processed meat. Although they are beneficial and safe at permitted levels, they can be carcinogenic when used in excess. Large doses of nitrites can also lead to a condition known as methemoglobinemia. The aim of this study is to determine whether the nitrite content in four locally available brands of processed chicken products are within the permitted levels. Nitrite content was determined using Griess assay in four brands of chicken sausages (S1, S2, S3, S4), ham (H1, H2, H3, H4) and meatballs (M1, M2, M3, M4) available in the local market. Nitrites produce a characteristic dark pink colored complex when reacted with N-1-napthylethylenediamine dihydrochloride (NED) under acidic conditions when subjected to Griess assay. The absorbance was measured at 540 nm using a UV-Visible spectrophotometer, and nitrite concentration was determined. A calibration curve was obtained by reacting standard solutions of NaNO2 with the Griess reagent, and measuring the absorbance at 540 nm. The obtained results show sausage brands S1, S2, S3 and S4 contained 31.1 mg/kg, 43.1 mg/kg, 96.1 mg/kg and 1.2 mg/kg of nitrite and chicken meatball brands M1, M2, M3 and M4 contained 2.1 mg/kg, 68.8 mg/kg,

134.4 mg/kg and 78.5 mg/kg and chicken ham brands H1, H2, H3, H4 contained 5.0 mg/kg, 42.9 mg/kg, 16.0 mg/kg and 5.3 mg/kg. According to the Code of Federal Regulations Title 21, the amount of sodium nitrite present should not exceed 200 mg /kg (ppm) in processed meat. According to our results, the nitrite content of all brands of processed chicken used in this study were within the permitted levels.

Keywords Processed chicken, Griess Assay, Nitrite

Figure 1. Nitrite content in processed chicken products

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Sorptive removal of p-nitroaniline from aqueous matrices by using acid modified tea waste biochar

Y D Block, B Dissanayake, C Peiris , S R GunathilakeCollege of Chemical Sciences, Institute of Chemistry Ceylon, Rajagiriya


Para-Nitroaniline (PNA) is one of the most widely used synthetic precursors in the pharmaceutical industry which has been identified as a contaminant of emerging concern (CEC) due to its toxicity. Slow pyrolyzed tea-waste biochar (BC), modified by shaking with 5M hydrochloric acid for 24 h at 50±5 °C, was used for the sorptive removal of PNA from aqueous systems. The experiments were conducted by shaking the PNA solutions with the relevant BC of particle size 0.500 – 1.000 mm at a given temperature and given time and all the readings in pH, time and isotherm experiments were triplicated. The BC were prepared under two temperatures, 300 and 500 °C (denoted as HCl300BC and HCl500BC, respectively). Results were compared with raw BC produced at the above temperatures (RAW300BC and RAW500BC) and it showed that high pyrolysis temperature reduced the surface functional groups (SFGs) of the BC whereas HCl modification did not destroy the SFGs. A mixing period of 24 hours was used in kinetic adsorption studies. The adsorption best fitted into pseudo second order (PSO) kinetics (R2 ranging

from 0.92 to 0.99) indicating a chemisorptive dominance. The highest rate was observed for (HCl300BC) with a rate constant of 0.00748 g mg-1 min-1. Highest sorption of raw BC was observed in RAW300BC at an acidic pH of 2 as 1.66 mg g-1, indicating hydrogen bond formation with oxygenated surface functional groups (O-SFGs) as the dominant sorption mechanism. Pore filling mechanism governs the adsorption of HCl300BC since the surface area of BC increases upon HCl modification by breakage of pores and cleansing of BC surface by removing inorganic mineral ions. However, the mechanism for the adsorption of PNA onto HCl500BC remains unclear. The Langmuir isotherm model fitted well for all sorptions (R2 => 0.99). Among produced raw BC, HCl300BC showed the highest Langmuir sorption capacity of 5.31 mg g-1 which was enhanced by 58.68% upon HCl post modification.

Keywordsbiochar, p-Nitroaniline, post modification, sorptive removal


Microwave and open vessel digestion methods for biochar and activated carbon

P D Wathudura1, C Peiris1,2, S R Gunatilake1, M N Kaumal2

1College of Chemical Sciences, Institute of Chemistry Ceylon, Rajagiriya, Sri Lanka.2Department of Chemistry, University of Colombo, Sri Lanka


Activated carbon (AC) and biochar (BC) are low cost carbonaceous adsorbent material widely used for the removal of toxic metal ions from aqueous systems due to their highly porous nature. Depending on the feedstock used to produce these carbonaceous materials, the metal content present may vary. Various digestion methods have been incorporated to analyze the metal content of activated carbon and biochar though a proper method has not yet been established. This study was focused on finding a suitable method to totally digest the carbonaceous material and to evaluate the matrix effect. Both open vessel and microwave digestion

methods were carried out for BC derived from tea waste, king coconut husk, Douglas fir and AC using mixtures of nitric acid (NA), fuming nitric acid (FNA), sulfuric acid (SA) and hydrogen peroxide (HP) and their turbidity were measured. Lowest turbidities for open vessel digestions were observed for SA/HP mixture for low-temperature BC with no external heating (2.04 – 7.90 FNU). Microwave digestions provided satisfactory turbidity levels for NA, NA/SA mixture, FNA and FNA/SA mixture for all types of carbonaceous material (1.58 – 20.97 FNU). The matrix effects were compared using cadmium, copper and zinc using flame atomic absorption

26



Determination of the oxalate ion concentration in green leafy vegetablesJ V Liyanage, U K Jayasundara*

College of Chemical Sciences, Institute of Chemistry Ceylon, Rajagiriya, Sri LankaEmail: [email protected]

Kidney and gall stone diseases occurring in the urinary tract can be life threatening and are promoted by the existence of oxalic acid (oxalate ion) in green leafy vegetables. Plants that accumulate large quantities of oxalic acid generally contain high concentrations of oxalate ions and salts. Consumption of green leafy vegetables containing large amount of oxalate could be fatal to humans because of the formation of oxalate deposits in vital tissues or organs in the body. The patients diagnosed with kidney and gall stones are advised to control and limit green leafy vegetable intake 40 – 50 mg/day according to American Diabetes Association. Thus, the objective of the present study was to determine the oxalate ion content of seven green leafy vegetables, namely spinach (Spinacia oleracea), mukunuwanna (Alternanthera sessilis), gotukola (Centella asiatica), hathawariya (Asparagus zeylanicus), thebu (Costus speciosus), cabbage (Brassica oleracea), leeks (Allium ampeloprasum) commonly consumed in Sri Lanka. The raw materials for this study were purchased from local markets in the Central Province. The edible portion of plant material was dried, refluxed, extracted with diethyl ether, precipitated with a saturated calcium solution, and pH controlled solution was titrated with standard potassium permanganate solution in triplicate. The volume of potassium permanganate was used to calculate the amount of oxalate ion present in 20 g of each green leafy vegetable. According to the results, all green leafy vegetables contain about 88% or more of moisture content. The results also show measureable amounts of soluble oxalates present in spinach, gotukola, mukunuwanna, hathawariya, and in thebu while cabbage and leeks have less or undetectable amount of oxalate ions. According to the oxalate content, the plants can be classified into four groups as green leafy vegetables with high oxalate content such as spinach (456.88 ± 20.59 mg/20.00 g) and hathawariya (556.04 ± 3.69 mg/20.00 g); leafy vegetables with intermediate level of oxalate content such as mukunuwenna (184.67 ± 8.05 mg/20 g) and thebu

(139.83 ± 3.20 mg/20.00 g); leafy vegetables with low level of oxalate content as in gotukola (48.04 ± 0.00 mg/20.00 g), and leafy vegetables with undetectable content of oxalate such as cabbage and leeks. The green leafy vegetables which are commonly consumed by Sri Lankans have detectable and measurable amount of oxalate ions which exceeds the minimum permissible level for kidney and gall stone patients according to American Diabetes Association f. Except gotukola, all other green leafy vegetables with detectable oxalate ions, have several folds of recommended oxalate ions which is harmful for the human health.

Keywordsoxalate ion content, green leafy vegetables, kidney and gall stones, permissible level

spectrophotometry. Fuming nitric acid showed the lowest matrix effects for cadmium and copper (1.2 – 4.8 and 2.4 – 7.1, respectively).

KeywordsBiochar, activated carbon, low cost adsorbents, digestion, matrix effect, turbidity

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Influence of volatiles from brinjal host on the attraction of brinjal fruit and shoot borer- Leucinodes orbonalis Guenee

M S F Nusra1,2, P A Paranagama2, L D Amarasinghe3 and D N Udukala1*1College of Chemical Sciences, Institute of Chemistry Ceylon, Rajagiriya, Sri Lanka

2Department of Chemistry, Faculty of Science, University of Kelaniya, Sri Lanka3Department of Zoology and Environmental Management, University of Kelaniya, Sri Lanka


Brinjal fruit and shoot borer, Leucinodes orbonalis Guenee, is a major pest on brinjal, Solanum melongena in South and South-East Asia. Larvae cause enormous damage to brinjal pods and shoots and the population management is normally done with frequent application of insecticides. The synergism between insect pheromones and plant volatiles can increase the attraction of insect pests, offering new strategies for the development of more effective and reliable pest control programs. Volatile mediated foraging behaviour in insect pests is important when they target host plants. We hypothesized that the volatiles of brinjal may be functionally more important in host-finding behavior of their insect pest. Samples of brinjal (“Lena iri” variety) plant leaves, fruits, shoots and flowers were collected from the unsprayed brinjal field. Steam distillation method was used to extract the volatiles from shade dried brinjal leaves, shoots, flowers and fresh fruits. The behavioral responses of L. orbonalis moths were tested using host plant volatiles. Gas chromatography (GC) coupled with mass spectrometry (MS) technique was used for the identification of volatiles extracted from host plant brinjal. The GC oven was programmed at an initial oven temperature of 40 oC, increased at a rate of 1 0C/min to 50 oC, then increased at a rate of 4 oC/min to 210 oC, and then raised at a rate of 8 oC/min to a final temperature of 230 oC. MS data of eluted compounds were acquired and compared with the retention times of authentic standards and with mass spectra from NIST library. Bioassay using a modified Y-shaped olfactometer revealed that one day old virgin females, mated gravid females and males positively responded (attracted) to the host plant volatiles extracted from fruits, leaves and shoots but not to the volatiles of flowers. Each assay was repeated using 5 batches of insects (R=5), consisting of 6 insects per batch (n=6). It was shown that the mated gravid females were significantly attracted to all three volatiles (P<0.05). A minimum dose of 0.2 µl and maximum dose of 12 µl of leaf volatiles attracted 11% and 83% of mated gravid females, respectively while shoot

volatiles attracted 22% and 78% of mated gravid females to a minimum dose of 0.02 µl and a maximum dose of 8 µl, respectively. Fruit volatiles attracted 17% and 79% of mated gravid females to a minimum dose of 0.02 µl and a maximum dose of 8 µl respectively. The Multiple-Choice bioassay using a modified X-shaped olfactometer (n=15, R=5) revealed that all three types of moths highly preferred the volatiles extracted from fruits and among the three categories of moths, mated gravid females were highly attracted to all three volatiles. It was also shown that the peak activity of the adults was observed during 20.00 – 24.00 hrs and the experiments were conducted during the observed peak hours. GC-MS analysis of plant volatiles concluded that the volatile compounds belonging to different classes of organic compounds: hydrocarbons, green leaf volatiles (aldehydes, esters), alcohols, fatty acids and other volatiles. Responses of adult moths to the volatiles from host plant in the absence of visual cues or pheromone signals show us to focus solely on the importance of host plant volatiles to locate the plant.

KeywordsLeucinodes orbonalis Guenee, GC-MS, host plant volatiles, olfactometer, behavioral bioassay

28



Determination of antioxidant activity, phenolic content and pH in wine prepared from local beet

S R Gunasekara*, C S Udawatte, U S K WeliwegamageCollege of Chemical Sciences, Institute of Chemistry Ceylon


Beetroot (Beta Vulgaris) is a vegetable containing high amounts of biologically active compounds such as antioxidants, and polyphenols. It also contains vitamin C, fiber, inorganic nitrogen and anthocyanin, which have various health benefits. In this study, wine was prepared by fermenting beet, and the antioxidant activity, pH and total phenolic content of the wine was determined. Beetroot (500 g) was weighed, washed, peeled and cut into small pieces after which they were blended and beet pulp was obtained. Deionized water was boiled and cooled to 35-40 ºC. The beet pulp was placed batch wise on cheesecloth and squeezed. About 250 ml of the juice was collected into a measuring cup. 100 ml of previously boiled and cooled DI water was added to the pulp, and another 250 ml of juice was collected by filtering the pulp again. The two extracts were combined. 1g of yeast was added to 200 ml of previously boiled lukewarm DI water, and kept for 20 minutes. Thereafter, it was added to the beet juice and total volume was made up to 300 ml by adding boiled and cooled DI water. The beet juice and yeast were transferred to glass bottles that were previously washed and autoclaved, and kept in a dark place for 2 weeks to ferment. Antioxidant Assay was carried out and Total Phenolic Content was determined. BHT (25 mg) was dissolved in methanol to prepare a stock solution (1.0 mg/mL) thereafter which a series of standard solutions were prepared. The solutions were kept in the dark for 10 minutes at room temperature. A solution of 0.08 mg/mL 2,2-Diphenyl-1-picrylhydrazyl (DPPH) was prepared in methanol. The absorbance at 517 nm was measured using a UV visible spectrometer with methanol as the blank. 2.5 mL of stock wine was diluted to 25 mL in a volumetric flask with deionized water. 1.5 mL of diluted beet wine was mixed with 2 mL DPPH and 0.5 mL methanol. Deionized water was used as the blank. Absorbance was measured at 517 nm and the % inhibition was calculated. Total Phenolic Content was determined as gallic acid equivalents (GAE). 1 mL of beet wine was diluted to 10 mL with deionized water. 0.5 ml Folin-Ciocalteu reagent was added to 0.5 ml of sample, and incubated in a dark place for 5 minutes at room temperature. Next, 0.5 ml of

6% sodium carbonate and 2.0 mL of deionized water was added. The mixture was kept in a dark place for 1 hour at room temperature. The absorbance was measured at 765 nm. The pH of the wine was determined using a pH meter. The beet wine has 63% inhibition which indicates the presence of a high concentration of antioxidants. According to Folin- Ciocalteu method, the total phenolic content of the beet wine is 0.0046 GAE. The wine is mildly acidic, and the pH is 4.6.

AcknowledgementThis work was supported by Institute of Chemistry Ceylon. The authors thank Mr. Chandana Perera for technical assistance.

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Determination of microbiological and chemical parameters of ready-to-serve fruit drinks and carbonated beverages commercially available in Sri Lanka

F L Radiyya1, E G Somapala1, M Perera3, S P Deraniyagala1,2*1Institute of Chemistry Ceylon, College of Chemical Sciences, Rajagiriya, Sri Lanka.

2Department of Chemistry, University of Sri Jayewardenepura, Sri Lanka.3MicroChem Laboratories (Pvt) Ltd., Sri Lanka.

*Email : [email protected]

As no previous studies have been reported in Sri Lanka to date related to the above title, this project was undertaken to create public awareness of the hazards associated with ready-to-serve fruit drinks and carbonated beverages. This study evaluated some chemical and microbiological parameters of three popular brands of ready-to-serve fruit drinks and three popular brands of carbonated beverages manufactured in Sri Lanka as per SLS specifications (SLS 729:2010 UDC 663.81 and SLS 183 : 2013 UDC 663.64.057). The ready-to-serve fruit drinks and carbonated beverages were screened quantitatively for the presence of sulphur dioxide and benzoic acid content1 using titrimetric method (iodometric) and sublimation/titration, respectively. The level of heavy metals such as lead and cadmium were determined using atomic absorption spectrophotometry. The microbiological parameters, aerobic plate count (APC), yeast and molds, total coliforms and Escherichia coli were conducted as per ISO (International Organization for Standardization) methods. In this study three different batches from each brand was tested microbiologically and for heavy metals (one sample from each batch) whereas three different batches from each brand was analyzed in triplicate for preservatives (three samples from each batch). The study showed the presence of sulphur dioxide in all six brands (0-20 mg/kg), which was less than the limit (50 mg/kg). Benzoic acid was also found in all six brands (7-10 mg/kg) which was less than the limit (120 mg/kg). The APC was less than the limit in most samples. Yeast and molds were detected in two brands and coliforms in all six brands. Cadmium, Lead and Escherichia coli were absent in all six brands. This proved all six brands were free from fecal contamination and heavy metals. Since certain microbiological parameters did not conform to SLS specifications we suggest that the manufacturers should improve quality control procedures adopted in their organizations to ensure the product quality.

Keywordsready-to-serve fruit drinks, carbonated beverages, microbiological parameters, preservatives.

References1. Tfouni, S. A. ; Toledo, M. C. Determination of

Benzoic and Sorbic Acids in Brazilian Food. Food Control 2002, 13 (2), 117–123

30



Chemical and microbiological contaminants and preservatives in commercially available tomato sauces

F N Iqbal1, E G Somapala1, M Perera3, S P Deraniyagala1, 2*

1Institute of Chemistry Ceylon, College of Chemical Sciences, Rajagiriya, Sri Lanka.2Department of Chemistry, University of Sri Jayewardenepura, Sri Lanka.

3MicroChem Laboratories (Pvt) Ltd., Sri Lanka.*Email : [email protected]

Tomato sauces are a part of the processed food industry which is currently amongst the fastest growing both for consumption and export making it a highly profitable industry. The present work was aimed to determine microbiological and some chemical parameters of commercially available tomato sauces. The study was conducted with four (4) different brands of sauces and was compared with the limits stated in the Sri Lanka Standard 260 : 2008 (UDC 664.871.6 : 635.64). All tests were conducted according to the International Organization for Standardization (ISO) and Association of Official Analytical Chemists methods (AOAC). The parameters that were ascertained are benzoic acid and sulfur dioxide content used as preservatives, E. coli, the Howard Mold Count, and a trace metal analysis conducted for cadmium. In this study three different batches from each brand was tested microbiologically and for heavy metals (one sample from each batch) whereas three different batches from each brand was analyzed in triplicate for preservatives (three samples from each batch). The study showed the presence of sulphur dioxide

in all four brands (2-52 mg/kg) which was less than the limit (100 mg/kg). Benzoic acid was also found in all four brands (40-357 mg/kg) with high variations which may be due to manufacturing inconsistencies and two brands from one batch exceeded the limit (250 mg/kg). In case where the samples exceeded the quoted limit a percentage of the total preservatives (sulphur dioxide and benzoic acid) was required to be calculated which should not exceed 100%. Results showed samples from one batch in one brand exceeded 100% whereas the other did not. The Howard mold count, E. coli and cadmium were absent in all four brands. Of the four brands tested, for three brands parameters tested conform to SLS specifications whereas for the other brand benzoic acid level from a sample from one batch did not conform to the limit specified by SLS standard. All different brands were compared with each other using the Null-Hypothesis, t-tests and f-tests for statistical analysis.

Keywordstomato sauce, preservatives, cadmium, E. coli, Howard mold count


Plumbagin functionalized silver nanoparticles for potential antimicrobial applications

I N Dammulla1, L B A E Bogahawatta2, C P Gunasekara2,3, M M Weerasekara2, C Padumadasa1,3, N M S Sirimuthu1*

1Department of Chemistry, University of Sri Jayewardenepura, Sri Lanka 2Department of Microbiology, University of Sri Jayewardenepura, Sri Lanka

3Center for Plant Materials and Herbal Products Research, University of Sri Jayewardenepura, Sri Lanka *Email: [email protected]

Plumbago indica L. called “Rathnitul” in Sinhala is a medicinal plant belonging to the family Plumbaginaceae that is extensively used in the traditional system of medicine in Sri Lanka. Plumbagin is a naturally occurring hydroxynaphthoquinone which is predominantly found in the roots of Plumbago indica L. Plumbagin has been proven to possess remarkable pharmacological

properties which include antimicrobial, anticancer, anti-inflammatory, antioxidant, and antiparasitic properties. However, high volatility, poor oxidative stability, poor bioavailability, less target specificity and high toxicity of plumbagin have limited its use in therapeutic applications. In recent years, enormous attention has been drawn towards the functionalization of natural

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products. Thus, the functionalization of plumbagin with an appropriate nanomaterial is a promising strategy to overcome the problems associated with plumbagin when used alone, and to enhance the therapeutic potential of plumbagin in its use for therapeutic applications. Silver nanoparticles (AgNPs) have garnered significant interest of the scientific community for synthesis of “hybrid drug molecules” as they act as good nanocarriers of the drugs leading to targeted drug delivery. Furthermore, the unique physical, chemical, optical and biological properties of AgNPs have made them excellent candidates in biomedical applications as antimicrobial and anticancer agents. Here, we report a preliminary study conducted to synthesize plumbagin functionalized AgNPs to be used in antimicrobial applications. In this study plumbagin was extracted from the roots of Plumbago indica and crude plumbagin was purified by recrystallization.1 The identity and purity of plumbagin were confirmed by GC/MS, FT-IR and UV-Vis spectra. AgNPs were synthesized by reduction of silver nitrate with hydroxylamine hydrochloride following the Leopold-Lendl method.2

Synthesized AgNPs gave rise to the characteristic surface

plasmon resonance (SPR) absorption peak at 410 nm in the UV-Vis spectrum. Vortex mixing of AgNPs with plumbagin in 1: 2×105 molar ratio at 1600 rpm for 2 hours at room temperature led to the successful functionalization of AgNPs with plumbagin, resulting a significant difference in the UV-Vis and FT-IR spectra. Since both materials possess notable antimicrobial properties, an enhanced antimicrobial potential is expected from plumbagin functionalized AgNPs due to the synergistic effect. Investigation of the antimicrobial potential of plumbagin functionalized AgNPs is currently in progress. KeywordsPlumbagin, Silver nanoparticles, Functionalization, Antimicrobial

References1. Padumadasa, C.; Abeysekera, A.; Meedin, S.,

International Journal of Ayurveda and Pharma Research 2016, 3 (12)

2. Leopold, N.; Lendl, B., The Journal of Physical Chemistry B 2003, 107 (24), 5723-5727.


Cytotoxic potential and apoptotic effect of Barringtonia asiatica seed kernel against HepG2 cell line

R Paramasamy1*, S Ekanayake1, S R Samarakoon2

1Department of Biochemistry, Faculty of Medical Sciences, University of Sri Jayewardenepura, Nugegoda2Institute of Biochemistry, Molecular Biology and Biotechnology, University of Colombo, Colombo


Liver cancer causes significant morbidity and mortality among humans worldwide due to lack of effective therapeutic strategies for control and treatment. According to World Health Organization, 7.5 % of male deaths in Sri Lanka are due to liver cancer and mortality rate due to liver cancer is increasing each year1. The need for pharmacological agents has necessitated the search for newer therapies from natural products. Barringtonia asiatica is a species of Barringtonia native to mangrove habitats along tropical coasts and islands of the Indian Ocean and is grown as an ornamental plant in Sri Lanka. Crude methanolic extract (CME ;15 g powder / 40 mL MeOH; 24 hrs; dried at 45oC)) and an isolated fraction (MPLCBA-3 fraction) of CME of B. asiatica, using medium pressure liquid chromatography (MPLC) have showed cytotoxicity against HepG2 cell line2. The present study investigated the mechanisms of cytotoxicity of CME and MPLCBA-3 fractions from

Barringtonia asiatica seed kernel against HepG2 cell line. Cytotoxicity was assayed with LDH assay with CME (10, 25, 50, 75, 100, 125 ppm) and MPLCBA-3 fraction (2.5, 5, 10, 15, 20, 25 ppm). Mechanisms of action were determined using DNA fragmentation analysis with CME (25, 50 and 100 ppm) and MPLCBA-3 fraction (5, 10 and 20 ppm) and fluorescence microscopic analysis with CME (10, 20, 40 and 80ppm) and MPLCBA-3 (5, 10, 20, 40 ppm] against the liver cancer cell line using standard procedures3,4,5. The total LDH activities in the medium when HepG2 cells were treated with CME (10-125 ppm) and MPLCBA-3 fraction (2.5-25 ppm), increased from 53.1%-87.3% [34.2%] and 53.9– 66.4% [12.5%], respectively against the controls. LDH activity increased with increasing concentration of the cytotoxic fraction confirming cell membrane damage by CME and MPLC fractions. However, MPLCBA-3 fraction caused more damage compared to CME. AO/EB staining

32


showed uniform green cells in the control HepG2 cells whereas apoptotic cells in the early stage were marked by yellow-green (10 ppm of CME, 5, 10 ppm of MPLCBA-3) and apoptotic cells in the late stage were marked with concentrated and asymmetrically yellow-orange nuclei (20, 40, 80 ppm of CME, 20, 40 ppm of MPLCBA-3, 10 ppm of thymoquinone [control]) under fluorescence microscope. Thus, HepG2 cells after treatment with CME and MPLCBA-3 fractions indicated cell apoptosis. Control had intact nuclei with uniformly dispersed chromatin in HepG2 cell lines. DNA fragmentation is a feature of apoptosis. HepG2 cells treated with CME and MPLCBA-3 fraction of B. asiatica and thymoquinone indicated DNA fragmentation, confirmed due to smearing observed in the gel electrophoresis when compared to control. When comparing CME and MPLCBA-3 fraction higher fragmentation was observed with the MPLCBA-3 fraction. The cell membrane damage as indicated by high LDH activity also correlates to the observation made under fluorescence microscopic pictures. When considering fluorescence microscopic pictures stained with Hoechst stain, at higher concentrations of

MPLCBA-3 fraction (20 ppm), condensed nuclei were observed in the HepG2 cells. These correlated with gel picture of DNA fragmentation of MPLCBA-3 fraction in HepG2 cell lines where smearing indicated that DNA were fragmented. The morphological characteristics indicated that these extracts cause apoptosis while biochemical changes linked with apoptosis included leaching of LDH indicating membrane damage and DNA fragmentation. Thus, both crude methanolic extract and MPLCBA-3 fraction have shown high cytotoxic potential due to membrane damage and DNA fragmentation causing apoptosis of HepG2 cells.

KeywordsBarringtonia asiatica, DNA fragmentation, LDH assay, Fluorescence microscopic analysis

References1. WHO. (2014). Global Report on Surveillance.

Antimicrobial Resistance, Global Report on Surveillance, 85.


Durian and rambutan peels as potential sources of antioxidantsA A G Silva1, S Wickramaarachchi1, R N Attanayake2, C S K Rajapakse1*

1Department of Chemistry, University of Kelaniya, Sri Lanka2Department of Botany, University of Kelaniya, Sri Lanka


Rambutan (Nephelium lappaceum L.) and Durian (Durian zibethinus Murr.) are popular seasonal fruits grown in tropical countries, enriched in varieties of phytochemicals.1, 2 However, peels of these fruits cause unpleasant odors and serious environmental problems. As the exploration of bioactive compounds may lead to novel environmentally friendly drug discovery, the main objective of this study was to investigate the use of waste materials, durian and rambutan peels, as potential sources of antioxidants. Therefore, this work focused on determination of antioxidant activities of methanol extract of durian and rambutan peels using 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging assay and determination of its total polyphenolic contents (TPC) and total flavonoid contents (TFC). The chemical constituents of durian and rambutan peels were first extracted using methanol. Then the methanol extract was sequentially extracted with hexane, chloroform and methanol. The antioxidant activity of extracts of durian and rambutan peels and its fractions

were investigated using DPPH radical scavenging assay.3 TPC of methanol extracts of durian and rambutan peels were determined using Folin-Ciocalteu method4 and TFC of the extracts were analyzed using aluminium chloride method.4 According to the results, all the extracts and its fractions showed antioxidant activity. The IC50 values of methanol extract of rambutan peels (7.86±0.22 µg/mL), its hexane (13.49±0.52 µg/mL), chloroform (26.99±0.20 µg/mL) and methanol (30.85±0.97 µg/mL) fractions were lower than that of the control, butylated hydroxytoluene (BHT) (43.70±0.89 µg/mL). IC50 values of methanol extract of durian peels (100.48±4.16 µg/mL), its hexane (>1000 µg/mL), chloroform (161.99±6.23 µg/mL) and methanol (>1000 µg/mL) fractions were higher than that of the control, butylated hydroxytoluene (BHT) (43.70±0.89 µg/mL). TPC of methanol extracts of durian and rambutan peels were found to be 2.98±0.03 and 14.80±0.21 mg GAE/g dry weight respectively. Higher TFC was observed in methanol extract of durian peels (30.87 mg Catechin /g dry weight) than in methanol

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extract of rambutan peels (20.52 mg Catechin /g dry weight). The preliminary results of this study showed that the extracts of durian and rambutan peels are rich in compounds with potential antioxidant activity.

KeywordsAntioxidant activity, durian peels, rambutan peels, TPC, TFC

AcknowledgementFinancial assistance by the University of Kelaniya (Grant number RP/03/02/06/01/2018)

References1. Poovarodom, S., Haruenkit, R., Vearasilp, S.,

Namiesnik, J., Cvikrova, M., Martincova, O., et al., International Journal of Food Science and Technology, 2010 45, 921−929.

2. Ong, P. K. C., Acree, T. E., & Lavin, E. H., Characterization of volatiles in rambutan fruit (Nephelium lappaceum L.), Journal of Agricultural and Food Chemistry, 1998 46, 611−615

3. Samanthi, K., Wickramaarachchi, S., Wijeratne, E. and Paranagama, P., Journal of the National Science Foundation of Sri Lanka, 2015 43(2), pp.119–126

4. Herald, T. J., Gadgil, P., & Tilley, M., Journal of the Science of Food and Agriculture, 2012 92(11), 2326–2331.


Complexation between Fe2+ and 1,10-Phenanthrolin-5-amine and the quenching mechanism

G I P Wijesekera1, M D P De Costa1*, R Senthilnithy2 1Department of Chemistry, University of Colombo, Sri-Lanka

2Department of Chemistry, Open University of Sri-Lanka *Email: [email protected]

1,10-Phenanthroline and its derivatives are very important chelating bidentate ligands for transition metal ions.1 From previous studies, it has been investigated that Fe2+ make stable complexes with 1,10-Phenanthroline and its derivatives.2 1,10- Phenanthrolin-5-amine, which is a derivative of 1,10-Phenanthroline has an increased fluorescence quantum yield than its parent compound. Hence, to develop a fluorimetric method to analyze Fe2+, the behavior of 1,10 – Phenanthrolin-5-amine in the presence of Fe2+ was studied. Furthermore, the limit of detection, limit of quantification and the quenching mechanism were found using a calibration plot between Fe2+ and 1, 10 – Phenanthrolin-5- amine. Experiments were carried out in 95% acetonitrile solutions (pH 8.21). Excitation and emission wavelengths were at 267 nm and 515 nm, respectively. The fluorescence peak at 515 nm was quenched by Fe2+.The linear range was from 225.5 nM to 2850 nM with a detection limit of 7.8 nM at 3.3σ. Calculated limit of quantification was 235.36 nM. Temperature effect was an evidence for the static quenching of 1,10-Phenathrolin-5-amine by Fe2+. Quenching of the probe by Fe2+ at 278K, 288K, 298K, 303K and 313K were studied. The study showed that 1,10-Phenanthrolin-5-amine

can be used as a sensitive fluorescence sensor to detect Fe2+ ions in nano molar level. No observable interference is observed upon addition of 225.5 - 2850 nM of Fe3+ into 8 µM of 1,10-Phenanthrolin-5-amine solutions. Acknowledgement Faculty Research Grant (2017) of Faculty of Natural Sciences/ Open University of Sri Lanka is gratefully acknowledged for funds provided for this study. References1. Accorsi, G.; Listorti, A.; Yoosaf, K.; Armaroli, N.

Chem. Soc. Rev. 2009, 38 (6), 1690–1700. 2. Guang-Hua, Z.; Huang-Xian, J.; Bao-Fen, Y. Chin.

J. Chem. 2010, 21, 301-304.

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A study on the use of Bathophenanthroline as a fluorescence sensor for iron(II)

P P P Perera1, M D P De Costa1*, R Senthilnithy2 1Department of Chemistry, University of Colombo, Sri Lanka

2Department of Chemistry, Open University of Sri Lanka *Email: [email protected]

Although Fe2+ is present as a trace element, it plays a vital role in living systems. Therefore measurement of trace amounts of Fe2+ is very important for many biological and ecological studies. Bathophenanthroline (BPhen) forms a stable 1:3 red color complex with Fe2+ and appears as a promising colorimetric probe for Fe2+. Using colorimetry, it has been possible to detect 10 parts of Fe2+ in 109 parts of water (540 nM).1,2 Although fluorescence is much more sensitive than absorbance, no reported attempts were made to detect Fe2+ with BPhen, using a fluorescence method. Therefore this study was conducted to study the capability of BPhen as a fluorescence sensor for Fe2+. In this study, the fluorescence emission by BPhen was studied in 50% ethanol. At the excitation wavelength of 272 nm, BPhen gave a very high emission intensity with an emission maximum at 385 nm. A maximum fluorescence intensity was observed at a concentration of 0.15 µM, with 5 nm slit width for both excitation and emission. A 0.15 µM solution of BPhen was titrated with a 0.51 µM solution of Fe2+. A linear calibration curve could be obtained for this quenching process with a limit of detection of 9.0 nM of Fe2+. The linear range for the curve was 25 nM to 530 nM. The stoichiometry for the static quenching process was 1:3 as predicted according to literature.1 The binding constant for the complex was calculated using the experimental data as 8.1 × 1020 mol-3 dm9. An interference study was conducted with common fluorescence quenchers Ni2+, Co2+ and Cu2+ as well as Fe3+. The tolerance limits were 2 for Ni2+ and Co2+ while the values were 3 and 10 for Cu2+ and Fe3+, respectively, in terms of molar ratio of Fe2+. Further investigations should be carried on pH effect, solvent effect and temperature effect for this fluorimetric method although its sensitivity was impressive relative to the colorimetric method.

AcknowledgementFaculty Research Grant (2017) of Faculty of Natural Sciences/ Open University of Sri Lanka is gratefully acknowledged for funds provided for this study.

References1. Smith, G. F.; McCurdy, W. H.; Diehl, H. Analyst

1952, 77 (418), 418–422. 2. Perry, R. D.; Clemente, C. L. S. Analyst 1977, 102

(114), 114–119. 3. Zhu, G. H.; Ju, H. x.; Ye, B. F. A. Chinese Jounal

Chem. 2002, 20 (200002), 301–304.

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DFT study on classical Koshland retention mechanism of Linamarin hydrolysis

D L S Dinuka, C N Ratnaweera*College of Chemical Sciences, Institute of Chemistry Ceylon, Rajagiriya, Sri Lanka.


The hydrolysis of glucosidic linkage catalyzed by every carbohydrate-hydrolase is a reaction in which the product retains (α→α or β→β) or inverts (α→β or β→α) the anomeric configuration of the substrate. By releasing α-glucose and β-glucose, respectively, from the common substrates having α or β -glucosidic linkages, α-glucosidase and β-glucosidase are essentially distinguished. The distinction in the substrate specificities of the two enzymes was explained by the subsite affinities in their active sites.2,3 Amino acid sequences of the regions containing the catalytic sites in β-glucosidases from various sources were compared. Particularly this study was focused on validating the proposed mechanism by Koshland et al1 for glycoside hydrolysis reactions towards hydrolysis of “linamarin”. Quantum mechanics calculations in gas phase at B3LYP/6-311+G** level of theory for a simplified model of β-glucosidase active site with linamarin as the substrate, clearly indicated a stepwise mechanism for glycosylation. The rate determining step is nucleophilic substitution by Glu373 to form the covalently bonded enzyme substrate intermediate with protonation of the leaving group by Glu165. The geometrical configuration of the transition state for the enzymatic reaction was essentially the same as that found for a gas-phase model involving only the substrate and propionate/propionic acid pair to represent the catalytic glutamate/glutamic

acid groups. A reaction barrier of 29.65 kcal/mol was estimated by the model with the reaction energy being 15.25 kcal/mol for the glycosylation step of linamarin. Furthermore, it was found that the rate determining step is the first step owing to a higher barrier than the second, thus rationalizing the proposed Koshland retention mechanism. The mechanistic insights gained are valuable for not only understanding similar reaction mechanisms but also for rational design of novel linamarin analogs as potent anti-cancer drugs.

AcknowledgementFinancial assistance by Institute of Chemistry Ceylon, Sri Lanka (The research grant 17-1).

KeywordsDensity functional theory, Cyanogenic glycoside, Oxocarbenium ion, retaining glycoside-hydrolase

References1. Koshland, D. E., Biol. Rev. 1953, 28 (4), 416–436.2. Hermans, M. M. P.; Krooss, M. A; Beeurnens, J. Van;

Oostras, B. A; Reusersll, A. J. J., Biochemistry 1991, 266, 13507–13512.

3. Keresztessy, Z.; Brown, K.; Dunn, M. A; Hughes, M. A., Biochem. J. 2001, 353 (Pt 2), 199–205.

Figure 1. Geometries of transition states (TSg and TSdg) for the glycosylation and deglycosylation of double displacement retaining mechanism for hydrolysis of β-glycosides.1

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Fabrication and characterization of water stable multi-layer graphene oxide membranes by potassium ion crosslinking W R N M Bandara1, J A Liyanage1*, A R Kumarasinghe2

1Department of Chemistry, University of Kelaniya, Sri Lanka. 2Department of Physics, University of Sri Jayewardenepura, Sri Lanka.


Graphene Oxide (GO) was synthesized from vein graphite sourced from Bogala mine using Improved Hummer’s method. GO nano sheets are the oxidative exfoliation products of graphite. GO contains oxygenated functional groups attached to their basal planes and edges. GO membranes readily disintegrate in water, because GO sheets become negatively charged on hydration, and the electrostatic repulsion between GO sheets overcome the van der Waals attraction and hydrogen bonding. This represents significant obstacles to water treatment applications. Oxygenated functional groups allow GO nano sheets to be cross-linked with cationic metal ions. This improves the mechanical properties of the resulting membrane. The aim of this experiment is to stabilize the GO membranes via cross-linking with cationic metal ions. It was achieved by potassium ion cross-linking. On hydration with mechanical agitation GO membranes disintegrate immediately compared to the GO membranes cross-linked with potassium ions. At a high pH GO nano sheets become negatively charged and the cations are removed from nano sheets destabilizing the cation crosslinked nanosheets. Then cations become unable to crosslink GO nano sheets. Therefore it can be stated that aqueous acidic dispersions of GO are cross-linked with the selected cation, K+ to enhance the mechanical strength and water stability of GO membrane. Energy Dispersive X ray (EDX) was used to investigate for the incorporation of metal ions into the GO membrane. Scanning Electron Microscopy (SEM) images of low magnification indicate that cross-linked GO membranes have a wrinkled surface morphology compared to unmodified GO membranes. On crosslinking, the amounts of freely available carbonyl and epoxy functional groups decrease. Hence intensity of carbonyl and epoxy peaks have been decreased and peak positions have been shifted to lower wave numbers in the FTIR-ATR spectrum of potassium cross-linked membrane compared to unmodified membrane. Increase of elastic modulus was identified from tensile testing analysis of the modified GO membranes due to enhancement of mechanical strength on crosslinking.

Here, elastic modulus has been increased by 147% on crosslinking with K+. This confirms the ability of potassium ions to cross-link the GO membrane in the in-plane direction. Work is ongoing to further characterize the cross-linking by XRD, to identify the variation in d spacing on cross-linking and to find weather potassium ion cross-linking has been taken place in the stacking direction of GO membrane. KeywordsGraphene oxide, stability of GO in aqueous phase, cross-linked GO, mechanical strength, elastic modulus

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Synthesis and characterization of graphene oxide coated silica nanoparticles M A S N Weerasinghe1, J A Liyanage1*, A R Kumarasinghe2

1Department of Chemistry, University of Kelaniya, Sri Lanka 2Department of Physics, University of Jayawardenapura, Sri Lanka


Graphene oxide (GO) is capable of absorbing many common pollutants of water such as heavy metals and organic contaminants. However, graphene oxide membranes easily disintegrate in water and aggregates. This decreases its adsorption capacity and diminishes its practical applications. Therefore, to prevent the above problems graphene oxide is combined with silica nanoparticles. GO coated silica nanoparticles were characterized using Fourier Transform Infrared Attenuated Total Reflection Spectroscopy (FT-IR ATR), Scanning Electron Microscopy (SEM) and Energy Dispersive X-ray Spectrometry (EDXAS). FT-IR ATR of graphene oxide coated silica nanoparticles showed the presence of the following absorptions; peaks for silica at 1059 cm-1 for the asymmetric stretching of Si-O-Si bond and at 791 cm-1 for symmetric stretching of Si-O-Si bonds and peaks for graphene oxide at 3444 cm-1 for the stretching

vibration of hydroxyl (–OH) groups, at 1739 cm-1 for the stretching vibration of carbonyl (C=O) functional groups and at 1391 cm-1 for the epoxy (C-OH) groups. EDXAS data showed the presence of corresponding elements in each sample. EDXAS data of graphene oxide coated silica nanoparticles showed the presence C (carbon), O (oxygen), Si (silicon) as the main elements. According to SEM data, graphene oxide membranes on silica nanoparticles and the interphase between silica and graphene oxide could be clearly observed. Therefore, the successful synthesis of graphene oxide coated silica nanoparticles can be confirmed using SEM data, FT-IR ATR data and EDXAS data. KeywordsGraphene oxide, silica nanoparticles, coatings, water treatment, characterization


Binding interactions of coumarin derivatives with Hodgkin’s disease related protein ADAM-10; an in-silico approach

N M H N Thilakarathne*, C S Udawatte, C N RathnaweeraCollege of Chemical Sciences, Institute of Chemistry Ceylon, Rajagiriya, Sri Lanka


Hodgkin’s disease is a malignant tumor which is one of the most common cancers among the elderly and children. It is characterized by the overexpression of ADAM-10 protein with increased release of NKG2D ligand which causes impaired immune response against tumor cells.1 The selective inhibition of ADAM10 is one of the major approaches that is used to treat Hodgkin’s disease.1 However, there is still no synthetic selective inhibitor for ADAM10. This study focuses on the selective inhibitory activity of the 4,5- disubstituted-7-hydroxy coumarins on ADAM10 over ADAM17 and MMP9 in the sub site S1´ −S3´ of the MMP like catalytic site, using molecular docking approach. Docking software used were AutoDock Vina and Gold. The following crystal structures were obtained from PDB (Protein Data Base); extracellular

domain of ADAM10 (PDB ID: 6BDZ), cysteine rich domain of ADAM10 (PDB ID: 5LOQ), extracellular domain of ADAM17 (PDB ID: 1BKC) and human matrix metalloproteinase MMP9 (PDB ID: 1L6J). All nonstandard residues were deleted. The hydrogens and charges were added using UCSF chimera 1.9. The ligands and references were prepared using Spartan ’14 and the equilibrium geometry at the ground level was calculated with density functional (DFT) B3LYP and basis set 6-311+G** in vacuum. The hydrogen bonding, pi-pi stacked interactions and pi-alkyl interactions were considered as favorable interactions. Abbreviations of ligands are provided in Table 1.

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Figure 1. Interaction diagram for top scored docked pose for LIG2 with 1BKC

The scores given in Table 2 were derived using ‘Gold’ software. The results revealed that LIG1, LIG2, LIG3, LIG5 and LIG7 showed high possibility of inhibiting ADAM10 protein and that LIG1, LIG2, LIG5 and LIG7 showed selective inhibition of ADAM10 over ADAM17. It was also revealed that LIG4 showed selective inhibition

of ADAM10 over MMP9. Xxneed to cite Figure 1, authors please indicate placexx We can conclude that all coumarin derivatives showed higher possibility of binding to sub site S1´ −S3´ of the MMP like catalytic site of ADAM proteins than to the substrate binding cysteine rich domain to form a stable complex. All seven coumarin derivatives showed the possibility of being dual inhibitors of ADAM10 and ADAM17. LIG 1, LIG2, LIG3, LIG4 and LIG7 showed higher affinity to ADAM10 over ADAM17 and MMP9.

References1. Camodeca, C.; Nuti, E.; Tepshi, L.; Boero, S.;

Tuccinardi, T.; Stura, E. A.; Poggi, A.; Zocchi, M. R.; Rossello, Eur. J. Med. Chem. 2016.

2. Stiller, C., Eur. J. Cancer 1998, 34 (4), 523–528. 3. BIOvIA, D. S. Discovery Studio Modeling

Environment. San Diego, Dassault Syst. Release, 4. 2015.

Abbreviation IUPAC name of ligand

LIG1 7-hydroxy-5-methyl-4-phenoxymethyl-chromen-2-oneLIG2 4-(4-chloro-phenoxymethyl)-7-hydroxy-5-methyl-4-methyl-chromen-2-oneLIG3 4-(2, 4-dichloro-phenoxymethyl)-7-hydroxy-5-methyl-4-methyl-chromen-2-oneLIG4 4-(3-chloro-phenoxymethyl) -7-hydroxy-5-methyl-4-methyl-chromen-2-oneLIG5 7-hydroxy-4-(4-nitro-phenoxymethyl)-chromen-2-oneLIG6 7-hydroxy-4-(4-methoxy-phenoxymethyl)-chromen-2-oneLIG7 7-hydroxy-4-(2, 4-dinitro-phenoxymethyl)-chromen-2-one

REF1Methyl (5S, 6S)-5-(hydroxycarbamoyl)-6-(4-phenyl3,6-dihydro-2H-pyridine-1-carbonyl)-7-azaspiro[2.5]octane-7-carboxylate

REF2(2R)-N-[(1S)-2, 2-Dimethyl-1-[(methylamino) carbonyl]-propyl]-2-[(1S)-1-[formyl (hydroxyl) amino] ethyl]-5-phenylpentanamide

Table 1: Ligands and their abbreviations

Table 2: CHEMPLP scores of the highest scored docking complex poses

Ligand

CHEMPLP score of best docking complex poses extracellular domain of ADAM10

cysteine rich domain of ADAM10

extracellular domain of ADAM17

human matrix metalloproteinase

MMP9 LIG1 57.50 39.23 77.31 65.35LIG2 57.68 43.89 75.31 66.71LIG3 55.40 43.89 66.47 63.31LIG4 60.73 42.97 79.83 59.30LIG5 57.72 51.33 78.80 64.94LIG6 56.45 43.03 88.64 67.55LIG7 57.59 40.14 78.75 60.19REF1 58.04 52.15 84.50 80.23REF2 65.35 51.49 79.26 51.96

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A computational study on the inhibition of MCL-1 anti-apoptotic protein to activate apoptosis in cancer cells via commercially available natural product

derivativesM S V Costa*, C N Ratnaweera, C S Udawatte

College of Chemical Sciences, Institute of Chemistry Ceylon*Email: [email protected]

Bcl-2, BCL-XL and MCL-1 (Myeloid cell leukemia-1) are important anti-apoptotic proteins. The objective of this research was to identify commercially available natural product derivatives to inhibit MCL-1. Ligands were obtained from the ZINC12 database which provides 30793 chemically modified, commercially available natural product derivatives. Compound S63845, which binds with high affinity to the BH3 binding groove of MCL-1 was the reference. Initial docking was carried out using GOLD Suite v5.3 with Hermes v1.7.0. Crystal structures for MCL-1, Bcl-2 and Bcl-XL were obtained through RCSB PDB server. The single ZINC database SDF file was split into 20 SDF files for the ease of docking using MayaChemTools with Perl scripts from Strawberry Perl. Protein was prepared for docking by removing attached ligands and water molecules, and by adding hydrogen atoms. The binding pocket was defined by a predefined list of residues. CHEMPLP85 scoring function was selected for docking. S63845 was optimized to obtain the equilibrium geometry with Spartan’14 v1.1.0 applying Hartree-Fock 3-21G force field, and used for molecular docking with both GOLD Suite v5.3 and AutoDock Vina. 75 ligands were selected from initial docking and optimized using RESP ESP charge Derive Server (R.E.D. Server). Default Project.config and System.config files were used for the optimization with Gaussian 2016 (B01) version, and docked with Bcl-2 and Bcl-XL to determine specificity to MCL-1. Drug-like properties, absorption, distribution, metabolism, and excretion, of ligands and reference compound were analyzed with SwissADME server and DruLito software. Molecular dynamics simulations were carried out using Amber 16 suite. The system was solvated

by TIP3P cubic boxes and water box size was 8 x 8 x 8Å. Neutralization was done using tleap by adding required charges. A salt concentration of 0.10 M was maintained. System minimization was executed using sander module while heating, and equilibration and production were carried out using pmemd.cuda module. Molecular dynamics were performed on Nvidia GTX 1080 graphics processor. The system was minimized for 10000 steps with a 500 kcal/molÅ2 force constant restraint, and then minimized for another 4000 steps without any force constant limitation. Heating was under NVT conditions from 0K to 300K with a weak force constraint of 10 kcal/mol Å2. With pmemd module, the system was equilibrated under NPT (number of molecules, pressure, and temperature) conditions for 1 ns, and equilibrated until time vs. RMSD curve showed a stable horizontal gradient. Production step was performed under NVT conditions with SHAKE algorithm applying hydrogen constraint. Blind docking was performed, and search space of 100×100×100 Å box was defined. Three MCL-1 specific ligands were identified; N-[[(2R,3S,4R)-4-(dibenzylamino)-3-hydroxy-tetrahydrofuran-2-yl]methyl]-3,3-dimethyl-butanamide (ZINC77263702), 7-benzyl-1-[[4-[(7-benzyl-3-methyl-2,6-dioxo-purin-1-) methyl] phenyl] methyl]-3-methyl-purine-2,6-dione (ZINC33354648) and N-[[(2R,3S,4R)-4-(dibenzylamino)-3-hydroxy-tetrahydrofuran-2-yl]methyl]benzamide (ZINC77263752). These ligands have demonstrated the potential to be used as selective inhibitors for MCL-1, and exhibit far better drug-like and ADME properties compared to the reference compound.

Figure 1. Blind docked positions of ligands with MCL-1; S63845 (a), ZINC77263702 (b), ZINC77263752 (c) and ZINC33354648 (d)

a b c d

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Fifteenth Convocation of the College of Chemical Sciences25th February 2019 BMICH

Welcome address by the President, IChemC Convocation address by the Chief Guest

Valedictory Speeches

Graduate Chemists

Professor Sudantha LiyanageProfessor Sudantha Liyanage Emeritus Professor Deshabandu Tuley de SilvaEmeritus Professor Deshabandu Tuley de Silva

DLTC Diplomates

Shireen Jayasuriya Gold Medallist DLTC batch top

Ms. M A F Mushrifa Ms. M C VidushaniMs. M A F Mushrifa Ms. M C Vidushani

Graduate Procession Academic Procession

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Fifteenth Convocation of the College of Chemical Sciences

Convocation AddressEmeritus Professor Deshabandu Tuley de Silva, C.Chem., F.I.Chem.C.

Past President, Institute of Chemistry CeylonChancellor, Wayamba University of Sri Lanka

I am pleased to be amongst you on this 15th Convocation Ceremony of the College of Chemical Sciences of the Institute of Chemistry, Ceylon for two reasons. First of all because this College was established during my tenure of Office as the President of the Institute where Professor JNO Fernando who I consider as the Founder Leader of the Graduateship Course was appointed as the Honorary Dean. Secondly, because I could not refuse the kind invitation of my former student, Professor Sudantha Liyanage your present President, although it was a very belated invitation. Professor Liyanage, thank you very much for your invitation. Let me also propose for your kind consideration that our Distinguished Chemists be recognized in the future so that our graduands would value them as models who have pursued studies in Chemistry. The College has reached a major milestone as it is to be accredited to University status to offer the B.Sc. Special degrees in chemistry. I wish to pay tribute to Professor JNO Fernando for steering this College admirably in its formative years with dedication, tenacity and dynamism. Dear Graduands, congratulations on your successful completion of one chapter of your career. Today you will celebrate remembering the many challenges you have overcome and the hard work put on to achieve this distinct success. Please remember with gratitude the assistance and encouragement that you received from your dear parents, well-wishers, academic staff and friends as you enter the world to make a success of your career. Your parents and siblings have sacrificed a lot and encouraged, to contribute to what you are today. Can I request everyone who is graduating today, to stand up and give a big round of applause to your parents as a grateful appreciation for all what they have done in assisting you to get this achievement. Thank you. Those of you who want to continue your postgraduate studies have yet to go through another round of determination and dedication. Presently, you may also have to reflect on the inspiring words of advice given to you about the next stage of your career, to make it to be successful. I wish that you will make the right choice so that you will be taking the path to a bright future.

To have belief and trust in yourself and being true to yourself are very important factors to success. You have to choose between doing well in life or exceptionally well in life to make you great. It is also necessary to realize the potential of what you can do in life and make yourself, your parents and our country proud. Those of you who will contribute to our scientific and technological manpower will be pleased to contribute to our national development by meeting the challenges of industrial growth and development. In order to accomplish the responsibilities entrusted upon you, you have to work hard with resoluteness, dedication, perseverance, initiative and innovativeness. The future of the country depends on you who are expected to be leaders, professionals, and productive scientists in the fields of chemistry and technology. Chemistry is considered as the central science because it deals with the composition, properties and transformations of all types of matter, which are all composed of chemical elements. Chemical knowledge of matter is essential to understanding of other branches of science. Chemistry includes numerous branches, some of which have a wide range of industrial and scientific applications. Some of you I am sure will undertake new ventures with innovative programmes, follow the path of your dream with hard work, determination and total commitment. I am sure you will make the best use of the knowledge you have gained here to attain professional success. Learning is a life-long process. Remember that you will have the occasion to learn at every stage of life and never miss this opportunity. My special thanks to all the parents who have come from different parts of our country to share the joys of success. I am sure that these graduate chemists will go out to the world to reach new heights, with the determination to give their best service to Sri Lanka and the global community. In order to hold your interest, I wish to share some insights from my own personal journey. As most of you, I sat for the then University Entrance Examination to pursue a career in medicine. There were no grades those days and the result was you pass or fail. Then

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we were called for a viva voce examination where no subject knowledge was tested but whether you should be selected to do medicine or bioscience. Although I won both the Physical science and Bio science prizes in College, I was selected to do bioscience. My teachers and I were disappointed but I took up the challenge with the determination of getting to the top of my unknown future career. Here I am now after pursuing a university academic career starting from being a probationary assistant lecturer, lecturer, senior lecturer, Professor, Head of Department, Dean of the Faculty and the President of the Campus and then as a Professor Emeritus. My aspiration to get to the top position was fulfilled when I was appointed by H.E. the President of Sri Lanka as the Chancellor of a University. I must confess that although I was first in class from year to year up to the University entrance class, I never received such accolades during my University career. Those who made judgements about me were proved wrong by lengths. My successes would give those who did not get first classes, a glimmer of hope that what matters is how you could set targets and steer with focus to attain them. It is also through failures, that I have learnt a lot about myself, my resilience, my strong will, my persistence and dedication, self-assurance etc. A lot of my notable successes have emerged from lessons learnt. Hard work, benevolence, resilience, persistence, eagerness to assist and not be jealous and being honest to oneself have contributed a lot towards achieving the set goals. These may be easy to preach but very hard to practice. Do not let fear of uncertainty and failure discourage you to recognize opportunities, but pursue them with passion until you achieve your goal. Whatever the context, keep on dreaming and work towards its achievement. Be aware that at times you may be attracted towards quick successes, short cuts and immediate wins, that could expose you to dishonesty in your search for success. Therefore, always be true to yourself and act with honesty. You must not simply try to get by in life leading to stagnation. Strive hard to excel in everything you undertake whether big or small. In your journey to success, you will face many challenges that should not discourage you but continue to your target with vigor and vitality. Failures could be the pillars of success. Hence when a project fails, learn from the mistakes and take the necessary remedial measures. My experience is that team work is more rewarding. Some companies have failed due to lack of team work

despite having the finest brains with them. It is therefore necessary to improve your skills to work as teams to contribute your best to the establishment. Do not for ever lose faith. I am convinced that the only thing that kept me going was that I enjoyed my work. Job satisfaction and faith in yourself are very essential to success. Remember that despite setbacks and disappointments do not give into peer pressure and change, but be true to yourself and live your life with integrity and honesty. Let me complement the Rector, Dean and Staff of the College of Chemical Sciences for their dedicated service in building up the scientific manpower requirements of our nation and wish them to excel in all their academic activities. Dear Graduands, you will now on, confront numerous challenges and encounter great opportunities, and it is for you to face them and succeed with resolve, hard work and diligence to make a rewarding and a bright future. I wish you all every success.

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36TH BATCH OF 149 GRADUATE CHEMISTS PASS OUT IN 2018First Class Honours (10)Ms. M. A. F. Mushrifa, Mr. N. M. H. N. Thilakarathne, Ms. I. L. Hettige, Ms. W. S. S. Perera, Ms. W. H. K. Perera, Ms. W. D. S. R. Perera, Ms. J. A. S. Gayara, Ms. W. R. P. Somarathne, Mr. M. J. M. Afnan, Mr. M. S. V. Costa

Second Class Honours (Upper Division) (20)Ms. B. D. Perera, Ms. U. V. de S. Jayasekera, Ms. K. D. N. Rathnaweera, Mr. K. R. J. Manuda, Mr. K. K. A. S. Jayathilaka, Ms. S. M. S. Nishadya, Ms. A. A. D. T. Abeysinghe, Ms. M. M. G. Kaumini, Mr. R. D. U. S. Deshapriya, Ms. W. G. B. K. K. G. Gunawardana, Ms. R. W. Ranaweera, Ms. M. M. F. Mubeena, Mr. M. S. D. Fernando, Ms. V. Wijayasekera, Ms. G. V. D. Anuththara, Ms. S. N. Nawalage, Ms. P. V. N. Kaushalya, Ms. R. M. K. P. Jayathissa, Ms. M. N. A. Seneviratne, Mr. K. M. Wickramasinghe

Second Class Honours (Lower Division) (20)Ms. Y. D. Block Mapalagama, Ms.N. N. M. Mendis, Mr. M. R. A. Basith, Ms. F. N. Iqbal, Ms L. L. J. de Silva, Mr. H. M. O. K. Herath, Mr. S. H. P. P. Sanjeewa, Ms. S. H. Basnagoda, Mr. H. M. M. M. B. Herath, Mr. M. P. B. N. Serasinghe, Ms. B. I. Keerawelle, Mr. K. D. T. Kavinda, Ms. Y. K. G. D. S. Yatiwelle, Mr. W. P. D. de Silva, Ms. G. M. Kallegoda, Ms. N. U. Deraniyagala, Ms. K. D. C. Madhushika, Ms. S. R. Gunasekara, Ms. M. R. A. Maryam, Ms. B. B. R. Perera

Pass (99)Ms. B. M. N. N. Basnayake, Ms. B. M. A. U. Amarathunga, Ms. C. N. A. Wijenayake, Ms. P. W. D. C. Asanthi, Ms. M. N. Jayathilake, Ms. S. N. D. De C. Dassanayake, Ms. D. M. G. H. K. Dissanayake, Ms. K. M. U. K. Kulasekara, Ms. C. K. Malaarachchi, Ms. W. V. D. S. D. Ranasinghe, Mr. E. U. H. Senavirathne, Ms. P. G. I. Lakmali, Ms. A. A. M. N. Amarasinghe, Ms. C. T. P. Liyanage, Ms. B. M. Samarakoon, Ms. R. S. K. Dharmaratne, Ms. A. A. D. N. Amarasinghe, Ms. T. M. H. Tennekoon, Ms. P. A. D. S. A. Wijayathilaka, Ms. U. M. N. Y. Alahakoon, Ms. R. A. S. H. Ranasinghe, Ms. N. P. K. Ranathissa, Ms. J. W. A. Udani, Ms. V. Lavanya, Mr. M. R. A. Shazvi, Mr. B. Venthan, Ms. B. M. D. T. Balasooriya, Ms. K. K. D. Chilki, Ms. A. A. N. Darshani, Mr. D. M. P. S. Dissanayake, Ms. M. N. S. de S. Goonetilleke, Ms. S. E. Herath, Ms. J. A. U. Heshini, Ms. H. D. Hettiarachchi, Ms. W. A. Jayasiri, Mr. S. P. H. S. Jayasuriya, Mrs. S. B. R. Keshika, Ms. S. Krishnamoorthy, Mr. N G Kodikara, Mr. R. R. T. W. W. M. R. N. D. B. Madawala, Mr. M. H. I. Mapatuna, Ms. P. A. R. T. Pamunugama, Mr. H. K. S. N. Perera, Ms. H. L. T. Perera, Mr. K. H. K. Perera, Mr. C. J. Premathunga, Ms. R. M. D. D. Rathnayake, Ms. B. A. D. S. Rathnapala, Mr. U. Sindhujan, Ms. W. M. C. M. Abeysekera, Ms. W. S. N. Alwis, Ms. M. N. B. Dharmasiri, Ms. G M S T Gallaba, Ms. M. M. F. Hassana, Mr. D. T. Kodisinghe, Ms. H. N. Maussawa, Ms. D. Ravishanker, Mr. K. Sasitharan, Ms. G. D. B. H. T. Senadeera, Ms. D. S. L. Sumanathilake, Mr. I. U. Thenabadu, Ms. K. S. Wijayanarayana, Ms. T. S. Shilpeswarage, Ms. S. R. H. Kandamby, Ms. M. R. A. I. C. Samaraweera, Ms. G. G. L. L. Gunarathne, Ms. K. A. V. N. Keenawinna, Ms. L. D. S. P. Rathnasekara, Ms. N. H. V. U. B. Nanayakkara, Ms. K. D. H. D. Ishara, Ms. B. S. S. Perera, Ms. M. B. S. S. Mendis, Ms. N. D. Jayasinghe, Ms. I. M. S. A. Illangakoon, Ms. D. G. C. S. Karunarathne, Mr. J. J. Jeevanantham, Ms. V. M. Egodage, Mr. S. Nigeathan, Ms. K. R. S. N. Fonseka, Mr. K. G. D. Dilhan, Ms. W. D. D. Prabodha, Ms. B. G. W. T. S. Piyasena, Mr. L. N. D. Silva, Mr. K. D. B. Dissanayake, Mr. D. M. B. S. B. Dissanayake, Ms. F. R. Ismath, Ms. W. G. K. Fonseka, Ms. S. K. M. N. Chathurika, Ms. S. S. Palihakkara, Ms. D. K. G. P. D. T. Kumari, Ms. K. A. D. E. B. Purnima, Ms. M. H. K. P. P. Maduratharangi, Ms. G. W. U. E. Nawarathna, Ms. K. M. N. P. Karunanayake, Mr. U. R. B. Weerasinghe, Ms. G. O. Jeewangika, Mrs. C. H. C. Anthony, Ms. F. R. Lafir, Mr. U. D. S. Dhilanka

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FIFTEENTH CONVOCATION AWARDS LIST 2018Graduateship Programme (Overall) Awards

First Shireen Jayasuriya Memorial Gold Medal 2018, for the Best overall Performance Ms. M. A. F. MushrifaSecond Graduateship Programme Silver Jubilee Commemoration Award Mr. N. M. H. N. Thilakarathne Third Graduate Chemist (25th passing out batch) Silver Jubilee Commemoration Award Ms. I. L. Hettige

Awards for Overall Excellence in Principal Areas in all Levels of Study (Theory)Professor J K P Ariyaratne Memorial Award for Inorganic Chemistry Ms. M. A. F. MushrifaProfessor Leslie Gunathilake Award for Organic Chemistry Ms. M. A. F. MushrifaHaniffa Award for Physical Chemistry Ms. M. A. F. MushrifaProfessors Saman & Asoka Pathiratne Award for Analytical Chemistry Ms. M. A. F. Mushrifa

Level 3 & 4 Overall (Theory) AwardsFirst Royal Society of Chemistry (Sri Lanka) Section Award Ms. M. A. F. MushrifaSecond Professor & Mrs. H W Dias Award Ms. W. H. K. PereraThird Rasanthika Nayomi Jayathissa Memorial Prize Ms. I. L. Hettige

Level 3 & 4 Overall (Practical) AwardsBest PerformersProfessor R S Ramakrishna Memorial Award Ms. W. G. B. K. K. G. GunawardanaMr. & Mrs. K Sivarajah & Family Award Ms. R. M. K. P. JayathissaB A Jayasinghe Memorial Award Mr. N. M. H. N. Thilakarathne

Good Performance Awards (donated by CCS)Ms. U. V. de S. Jayasekara, Ms. J. A. S. Gayara, Ms. M. A. F. Mushrifa, Ms. B. D. Perera, Ms. G. V. D. Anuththara, Ms. Y. D. Block Mapalagama, Ms. I. L. Hettige, Mr. K. R. J. Manuda, Mr. M. J. M. Afnan, Mr. W. P. D. de Silva, Mr. K. K. A. S. Jayathilake

Graduateship All Rounder AwardsDr. R O B Wijesekara Felicitation Fund Award for the Best All Rounder Mr. M. J. M. AfnanProf. Noel G Baptist Memorial Prize for the Second Best All Rounder Mr. K. D. T. Kavinda, Mr. M P B N SerasingheChamikara Wijesinghe Award for the third Best All Rounder Ms. N S Nawalage, Ms. W S S PereraCertificates of Honourable Mention Mr. N M H N Thilakarathne, Mr. S H P P Sanjeewa, Ms. L L J de Silva

Subject Prizes For Individual CoursesDr. Lakshman Ponnamperuma Prize for Special Topics in Inorganic Chem. I Ms. M. A. F. MushrifaDr. Sudath Kumarasinghe Memorial Prize for Special Topics in Physical Chemistry I Ms. M. A. F. MushrifaMr. & Mrs. N. I. N. S. Nadarasa Prize for Advanced Topics in Organic Chemistry Ms. M. A. F. MushrifaMicrochem Laboratories (Pvt) Ltd Prize for Environmental Chemistry Ms. M. A. F. MushrifaDr. Rohan Perera Prize for Chemical and Molecular Toxicology Ms. M. A. F. MushrifaMr. Cyril Suduwella Prize for Petroleum and Petrochemistry Ms. M. A. F. Mushrifa, Ms. K. D. N. RathnaweeraInstitute of Chemistry Ceylon Alumni Association North American Chapter Prize for Special Topics in Physical Chemistry II Ms. W. H. K. Perera, Ms. A. A. D. T. AbeysingheProfessor P. P. G. L. Siriwardena Prize for Special Topics in Inorganic Chem. II Ms. W. H. K. Perera

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Dr. S. Lakshman De Silva Memorial Trust Prize for Physical Organic Chemistry Ms. W. H. K. PereraDharmachandra & Thamarasa Gunawardhana Memorial Prize for Analytical Chemistry: Instrumental Analysis II Ms. W. H. K. PereraPincock Prize for Photochemistry Ms. W. H. K. PereraDr. Chandani Udawatte Prize for Clinical Herbal Products Development Ms. W. H. K. PereraDr. Premaratne Family Prize for Nanotechnology Ms. W. H. K. PereraW. R. O. Fernando Memorial Prize for Energetics & Kinetics Ms. I. L. HettigeDharmarathne Wasala Prize for Computational Chemistry Ms. I. L. HettigeMr. & Mrs. Gamini Gunasekara and Family Prize for General Chemistry Paper Ms. I. L. HettigeE. G. Somapala Prize for Food Chemistry and Technology Ms. I. L. HettigeMr. A G Gunarathna and Mrs. I K S R Ratnakalyani Prize for Research Methods Ms. A. A. D. T. AbeysingheMr. A. M. Jayasekara & Mrs. Kusum Aththanayaka Family Prize for Literature Survey in Chemical Sciences Ms. A. A. D. T. Abeysinghe

Rex Jayasinha Prize for Analytical Chemistry: Instrumental Analysis I Mr. N. M. H. N. ThilakarathneProfessor Eugene De Silva Prize for Industrial Chemistry and Technology Mr. N. M. H. N. ThilakarathneProf. Namal P Heenkenda and Prof. Ayanthi Navaratne Prize for Chem. Edu. Ms. L. L. J. De SilvaK. G. Karunasena Memorial Prize for Quantum Mechanics Mr. R. D. U. S. DeshapriyaDr. & Mrs. Swaminathan Memorial Prize for Information Technology Mr. S. Kalaivanan, Mr. M. J. M. AfnanVasanthan & Menaka Prize for Further Management, Economics and Finance Ms. S. M. S. NishadyaMarina & R. O. B. Wijesekera Prize for Molecular Biology and Biotechnology Ms. N. U. DeraniyagalaMr. & Mrs. E. Gajanayake Prize for Atomic Spectroscopic Methods of Analysis Mr. K. D. T. KavindaMrs. Mary Antoinette de Zoysa Prize for Materials Chemistry Ms. G. G. L. L. GunarathneN. M. S. Hettigedara Family Prize for Pharmaceutical and Medicinal Chemistry Ms. W. R. P. SomarathneMevan Pieris Prize for Polymer Chemistry and Technology Ms. B. D. PereraDenzil & Christobel Fernando Commemoration Prize for Agro Industries Ms. G. O. JeewangikaSusila Jayaweera Memorial Prize for Biochemistry II Ms. S. N. NawalageDr. Lakshmi Arambewela Prize for Research Project Beneficial for the Country Ms. W. S. S. PereraThambipillai Kandasamy Memorial Prize for Industrial Safety, Health and Environmental Technology Ms. G. M. Kallegoda

44TH BATCH OF 131 DLTC DIPLOMATES PASS OUT IN 2018

Clinical Laboratory Technology

Honours Pass (20)Ms. M T M Somathilaka, Ms. A Kantharatnam, Ms. N Abiramy, Ms. M M F Mifra, Ms. S A U C Senanayake, Ms. F N Nazar, Ms. B P Udani, Ms. M Y F Sumaiya, Mr. R J Anuradha, Ms. T G S Harshamali, Ms. A F Shahdiya, Ms. B C D Perera, Ms. H G D Wasana, Mr. J A D V L Ranasinghe, Ms. P U Kamanee, Mr. E P P Kumara, Ms. R Tharika, Ms. I M I Begum, Ms. R H A L Silva, Ms. M P M I Dayarathne

Merit Pass (37)Mr. M Z M Asmal, Ms. M T F Fahmidha, Ms. C D M Karunathilake, Ms. M A Shazrinnija, Ms. M B L F Shukriya, Mrs. L M S Madhupathumi, Ms. M I I Ihsana, Mrs. M A F Nufla, Mrs. H W K S Sandaruwani, Mr. M N M Bilaldeen, Ms. S B S Jootha, Ms. S N Hettige, Mr. P A B P Wimalarathne, Mr. W M C N Wickramasinghe, Ms. J M D H A Appuhami, Mr. M D I M Premasiri, Ms. H P U S Alahakoon, Ms. D L Hettiarachchi, Ms. A Nadaraja, Mr. H M N N Herath, Ms. T M Nagahawatta, Mrs. K H M S De Silva, Ms. K G J D Dassanayaka, Mr. R U C A De Silva, Mr. M M M Nifras, Ms. U L Sanjeewani, Ms. C Dusyanthy, Mr. W A H S Kumarasiri, Ms. M T Thahira Farwin, Ms. G W Madhusarani, Ms. M R F Mushrifa, Ms. B A I S Guyes, Ms. J D M Iresha, Mr. D M D P Dissanayake, Mr. M M M Fazly, Mr. M B Fazlan, Mr. P N K Manamperi

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Ordinary Pass (59)Ms. M F F Nimza, Ms. P A C N Ponnamperuma, Ms. H K S M R Fernando, Mr. S A C M Anas, Mr. W A S P Chathuranga, Ms. M M Najila Begum, Ms. R M D P S Rajapaksha, Mr. D C Baddagama, Ms. P D P P Kumari, Mrs. P Y Anuradha, Ms. C N Ranasinghe, Mr. P W I Erandika, Ms. A F Infa, Mr. P M C R Dissanayake, Ms. G K M R Malkanthi, Mr. S L A I Chathuranga, Mr. M A I Mohamed, Mr. M A A Mohammed, Mrs. N S D Kumari, Ms. G S K Dayarathna, Ms. K G N Kaumadi, Mr. T G S Jeewantha, Ms. R A N Chathurika, Mr. R D R T Wijithajeewa, Mr. T Srithevapriyan, Ms. G G P Sewwandi, Ms. N N M Jayathilaka, Mr. K W Hettihewa, Mr. C M Niriella, Ms. L C Christopher, Ms. D M S P Dassanayake, Mr. H M R T Priyadarshana, Ms. P V D Thanuja, Ms. V P C D Wickramasinghe, Mr. H S A Fernando, Mr. L M S S Gunasekara, Ms. M Kansa, Mrs. W A K R Swarnamali, Ms. M D Wickramasinghe, Mr. A P M Anas, Ms. M M F Azrah, Mr. P H K G P Deshappriya, Mr. M F M Fashan, Mr. C T E H M R R Herath, Mr. M M Ishaq, Mrs. P Keerthiga, Ms. R M S Kumari, Ms. D L A G N Liyanaarachchi, Mr. H A D S Logus, Mr. L H Madusanka, Ms. C N Nimalsiri, Ms. M T B De Silva, Ms. H M W P Premarathne, Mr. M F A Rahman, Ms. R M A C Rathnayaka, Mr. R M A I P Rathnayaka, Mr. I V A N Sanjeewa, Mr. T M R T B Tennakoon, Ms. W K A I L Wijesinghe

Industrial & Food Chemistry

Honours Pass (03)Ms. M C Vidushani, Mr. J H C R Jayamaha, Ms. M S G Perera

Merit Pass (04)Ms. C B Baranasooriya, Mr. M M L P Weerasekara, Ms. W G L K Walpola, Ms. N M M Nawarathna

Ordinary Pass (08)Ms. A I Angahawatte, Mr. B N Chandrasena, Ms. M D S K Mahabalage, Ms. L W Senanayake, Mrs. S M I C Senadipathi, Mr. K A C Ashoka, Mr. U K D H Udayanga, Ms. M R K J M M N D Madugalle

First in batch Dr. G C N Jayasuriya Award Ms. M C VidushaniSecond in batch Dr. Shenthe Shanmuganathan Appreciation Award Ms. M T M SomathilakaThird in batch MicroChem Laboratories (Pvt) Ltd. Award Mr. J H C R Jayamaha Prizes for Specialization Areas of StudyMr. Rohan K Fernando Prize for the best performance in Industrial and Food Chemistry Ms. M C VidushaniP D Luckmal De Zoysa Memorial Prize for the best performance in Clinical Laboratory Ms. M T M Somathilaka

Diploma in Laboratory Technology in Chemistry Award for the overall outstanding performance Mr. J H C R Jayamaha

DIPLOMA IN LABORATORY TECHNOLOGY IN CHEMISTRY PROGRAMME – 2016/18

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Tenth Inaugural Professorial Lecture Professor Hema M K K Pathirana, Senior Professor in Chemistry and the Chair Professor of Chemistry in the Department of Chemistry of University of Ruhuna delivered the Tenth Professorial lecture on Classical Inorganic Chemistry for Challenges in the 21st Century at the P P G L Auditorium on 24th January 2019.

Synopsis of the lecture

Some of the major challenges in the 21st century are the demand for energy, climate change, clean water scarcity, solid waste pollution and drugs for cancer and HIV. All the 118 elements in the periodic table come under inorganic chemistry and therefore it is impossible to visualize solutions to these problems without Inorganic Chemistry. Fossil fuel has been the major source of energy to date and demand for energy is increasing. Limited availability of fossil fuel prompts the search of new energy sources. The environmental issues arising during energy production require urgent solutions. The use of environmentally friendly renewable energy sources such as solar energy and biofuels have been identified as viable solutions in this regard. However, the low efficiency of solar cells and high production cost of biofuels are problems to be solved and can be clearly benefited from inorganic chemistry. Finding potable water has been a major challenge in many countries in today’s world. Contamination of available water resources by manmade chemicals further

aggravates this situation. Therefore, the development of non-persistent pesticides and the development of efficient degradation methods for persistent pesticides are desirable. Inorganic Chemistry has immensely contributed in these areas. Development of drugs for cancer and HIV are two significant challenges we face today. cis-platin has been an expensive drug used in the treatment for cancer. Synthesis of novel coordination complexes as alternatives for cis-platin is important. Prof. Hema M K K Pathirana presented how her research findings in classical inorganic chemistry could be applied as solutions for above mentioned challenges in the 21st century. This included production and characterization of thin films of inorganic semiconductors for solar cells and smart window applications, development of degradation methods for persistent pesticides, production of fish oil and biodiesel from solid wastes and, synthesis of coordination complexes of tellurium and selenium ligands and their potential applications.

Professor Hema M.K.K. PathiranaProfessor Hema M.K.K. Pathirana

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Chemistry Olympiad Sri Lanka 2019The third Chemistry Olympiad Sri Lanka (COSL) competition and training sessions were conducted on 23rd and 24th May 2019 at Adamantane House, Institute of Chemistry Ceylon, Rajagiriya. Thirty finalists were chosen for COSL-2019 after conducting a preliminary round on 27th January 2019 at twelve centers across the country. The theory and practical sessions were conducted prior to the final examination by academics attached to the College of Chemical Sciences of the Institute of Chemistry Ceylon. The winners of the COSL-2019 will be awarded at the 48th Annual Sessions of the Institute of Chemistry Ceylon scheduled to be held at the Sri Lanka Foundation on 10th June.

All Island Inter School Chemistry Quiz Contest - 2019The All Island Inter School Chemistry Quiz Contest was conducted on 29th May 2019 at Adamantane House, Institute of Chemistry Ceylon, Rajagiriya. Eleven students were chosen out of 475 students from nine provinces in the country who participated in the first round which was held on 27th January 2019. The three finalists of this contest will be awarded at the 48th Annual Sessions of the Institute of Chemistry Ceylon.

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LEVEL 1 - OVERALL AWARD LIST

First Prize & Nandawathie Jayaweera Memorial (open) Scholarship Ms. N A Seneviratne BandaraSecond Prize & Charles Jayaweera Memorial (open) Scholarship Ms. A N N MendisThird Prize & Professor R S Ramakrishna Memorial Scholarship Mr. D M JayasingheFourth Prize & Dr Dilanjan & Ms Gowrie Soysa Scholarship Ms. I W M L I WanigasooriyaSecond Charles Jayaweera Memorial (Southern Province) Scholarship Mr. R K A I A Rathnayake

MERIT BURSARIESMr. R K A I A Rathnayake, Mr. S A P H Samaraweera, Ms. H M D S D Heenkenda, Ms. K D U Kalpani, Ms. T J Ranasinghe, Ms. A P W Sulochana, Ms. K L H S Perera, Ms. M M Narayanan

SUBJECT PRIZES Emerine Fernando Memorial Prize for Principles of Physical Chemistry Ms. N A Seneviratne Bandara Mr. & Mrs. J. M. Ranasinghe Banda Prize for Mathematical Applications for Chemists Ms. N A Seneviratne BandaraGraduate Chemist Alumni Prize for General & Inorganic Chemistry Mr. B V C M BenaragamaSomawathi Mathew Memorial Prize for Biology for Physical Science Students Mr. B V C M BenaragamaProfessor & Mrs. S. Sotheeswaran Prize for Principles of Organic Chemistry Mr. B V C M BenaragamaBenette & Wimalin Prize for Mathematics for Biological Science Students Mr. B A M M WijesiriAbdul Salam Memorial Prize for Fundamentals of Physics for Chemists Mr. D M JayasingheDr. M. N. Kaumal Prize for Analog and Digital Electronics for Chemists Ms. M A I J Munasinghe, Ms. J P UsliyanageDr. Infas and Family Prize for Basic Concepts Ms. I W M L I Wanigasooriya


First Prize & W F Peiris Memorial Trust Scholarship Ms. L P L JayasingheSecond Prize & Prof W Pearlyn D Pereira Commemoration Trust Scholarship Ms. N D Lokuge

SUBJECT PRIZES Professor J. N. Oleap Fernando Prize for Physical Chemistry Ms. J A D I RanasingheProfessor Samitha P. Deraniyagala Prize for Inorganic Chemistry Ms. N D LokugeProfessor Siromi Samarasinghe Prize for Organic Chemistry I Mr. K M D I RodrigoMrs. Deepika Senaviratne and Family Prize for Titrimetric and Gravimetric Methods of Analysis Mr. M S V CostaProfessor Jayantha Welihinda Prize for Biochemistry Mr. M A UdayangaNureshan Dias Prize for Principles of Quantum Chemistry and Molecular Spectroscopy Ms. B A L C WimalarathneMrs. Yasawathie Satharasinghe Memorial Prize for Organic Chemistry ΙΙ Ms. P A U I WijesingheMikhail Tswett Prize for Separation Method and Applications of Spectroscopic Methods in Analysis Ms. A GaneshalingamHenry Ashmore Pieris Memorial Prize for Introduction to Management, Economics and Finance Ms. K K Nadeeshani

GRADUATESHIP EXAMINATIONS IN CHEMISTRY, 2018

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First Prize and Mandrupa & Oleap Fernando Hall Opening Scholarship Mr. P L Y V AlwisSecond Prize and Susila Jayaweera Memorial Scholarship Mr. M A UdayangaThird Prize and Graduateship Silver Jubilee Scholarship Ms. C J Lekamwasam

MERIT BURSARIES (in order of merit)Ms. U P Welikala, Ms. H K Medagedara, Ms. D H Thanipulli Arachchi, Mr. E A D N Mudujith, Ms. A. N. Wethalawe, Ms. D. N. Wijesekara

LEVELS 1, 2 & 3 BEST OVERALL PERFORMANCE, 2018

Institute of Chemistry President's Scholarship Mr. P L Y V Alwis

J N OLEAP FERNANDO MEMORIAL SCHOLARSHIPS

J N Oleap Fernando Memorial Scholarship for Level 1 Ms. N A Seneviratne Bandara J N Oleap Fernando Memorial Scholarship for Level 2 Ms. L P L Jayasinghe

First – CIC Charitable & Educational Trust Fund Entrance Scholarship Ms. K I L PereraSecond – Dr. Sudath Kumarasinghe Commemoration Scholarship Mr. W G K Kumara

Merit Bursaries I (in order of merit) (full)Ms. L C Atapattu, Ms. K R D H Wickramasinghe, Mr. A B Ranaweera, Mr. B D D K Budagoda, Ms. M P R Perera, Ms. A U Dharmarathne, Mr. M K S Jayasinghe, Ms. S N I Fernando, Ms. R G B M Ranatunga

Merit Bursaries II (in order of merit) (partial) Mr. M A N U Malaweera Arachchi, Ms. A G H N Seneviratne, Ms. S S D Fernando, Ms. A M H R S Karunarathne, Mr. M W K P A De Silva, Ms. S H Liyanage, Ms. T A U S Jayathilake, Mr. D M Jayasuriya

ENTRANCE SCHOLARSHIPS & BURSARIES - 2019

Vol. 36 No. 2, May 2019


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PUBLICATIONS OF THEINSTITUTE OF CHEMISTRY CEYLON

Monograph Title Author Price 01 Textile Fibers Mr T Rajasekeram Rs. 50/- 02 Principles of Food Preservation Prof U Samarajeewa Rs. 75/- 03 Biotechnology Prof C P D W Mathew Rs. 75/- 04 Recombinant DNA Technology Prof J Welihinda Rs. 75/- 05 *Natural Toxins in Foodstuffs Prof E R Jansz & Ms A S Perera Rs. 50/- 06 Fat Soluble Vitamins Prof E R Jansz & Ms S Malavidana Rs. 50/- 07 Nucleic Acid and Protein Synthesis Prof J Welihinda Rs. 75/- 08 Extraction of Energy from Food Prof J Welihinda Rs. 50/- 09 Corrosion of Materials Dr A M M Amirudeen Rs. 75/- 10 Vitamin C-Have all its mysteries Prof E R Jansz & Ms S T C Mahavithanage Rs. 75/- been Unravelled ? 11 *Environmental Organic Chemistry Prof S Sotheeswaran Rs. 150/-(US $3) 12 Enzyme Kinetics and Catalysis Prof (Mrs) S A Deraniyagala Rs.1 00/- 13 Insecticides Prof (Mrs) Sukumal Wimalasena Rs. 95/- 14 Organotransition Metal Catalysts Prof S P Deraniyagala Rs. 110/- & Prof M D P De Costa 15 Some Important Aspects of Prof L Karunanayake Rs. 75/- Polymer Characterization 16 *Hard & Soft Acids & Bases Prof (Mrs) Janitha A Liyanage Rs.100/- 17 Chemistry of Metallocenes Prof Sarath D Perera Rs. 65/- 18 Lasers Prof P P M Jayaweera Rs. 65/- 19 *Life and Metals Prof (Mrs) Janitha A Liyanage Rs.110/- 21 *Silicones Prof Sudantha Liyanage Rs. 65/- 22 *Pericyclic Reactions: Theory and Dr M D P De Costa Rs. 100/- Applications 23 Inorganic NMR Spectroscopy Prof K S D Perera Rs. 65/- 24 Industrial Polymers Prof L Karunanayake Rs. 75/- 25 *NMR Spectroscopy Dr (Mrs) D T U Abeytunga Rs. 65/- 26 Mosquito Coils and Consumer Ms D K Galpoththage Rs. 100/- 27 *Atomic Absorption Spectrometry Prof K A S Pathiratne Rs. 100/- 28 Iron Management on Biological Systems Prof (Ms) R D Wijesekera Rs. 100/- 29 Nutritional Antioxidants Prof. (Mrs) Sukumal Wimalasena Rs. 100/- 30 *f-Block Elements Prof Sudantha Liyanage Rs. 65/- 31 *Scientific Measurements and Calculations Prof (Mrs) S A Deraniyagala Rs. 120/- 32 Applications of Organometallic Dr. (Mrs.) Chayanika Padumadasa Rs. 60/- compounds in Organic Synthesis 33 Organosulfur Compounds in Nature Prof. S Sotheeswaran Rs. 200/- 34 Chemistry in the Kitchen Prof. S Sotheeswaran Rs. 200/- * - Second Edition /new print published on popular demand

CCS PUBLICATIONS 01 Functional Group Analysis in Prof A A L Gunatilake & Organic Chemistry Prof S Sotheeswaran Rs. 175/- 02 Zinc Metalloproteins Prof (Ms) R D Wijesekera Rs. 175/- 03 Conformational Analysis and Reactivity Prof S Sotheeswaran & Rs. 175/- of Organic Molecules Dr. (Ms) H I C de Silva 04 Marine Organic Chemistry Prof S Sotheeswaran Rs. 175/- 05 Molecular Rearrangements in Organic Dr. (Mrs.) Chayanika Padumadasa Rs. 175/- Synthesis 06 Principles of Classical Titrimetry Prof. H D Gunawardhana Rs. 175/- - Volume I Acid-Base Titrimetry 07 Principles of Classical Titrimetry Prof. H D Gunawardhana Rs. 175/- - Volume II Complexometric Titrimetry 09 Structure Elucidation of Organic Compounds Dr. S Wickramarachchi Rs. 175/- Using Spectroscopy: A work book 10 Chemistry of Five- and Six-Membered Dr. Chayanika Padumadasa Rs. 175/- Heterocyclic Compounds and their Benzo Derivatives

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RSC NEWSTHE ROYAL SOCIETY OF CHEMISTRY SRI LANKA SECTION1. MembershipAccording to the records sent to us from the parent body, a breakdown of the membership is as follows:-

Category NumberCChem, FRSC 09FRSC 03Chem, MRSC 07MRSC 27AMRSC 18Affiliate /Under Graduate. 10Total Membership as at July 2018 74

2. Committee of Management The following were elected to the Committee at the 57th Annual General Meeting held in July 2018.

Hony. Chairman - Mr. I M S Herath Hony. Secretary - Mrs. Aruni WickramanayakeHony. Treasurer - Dr. P Iyngaran

Committee Members Mr. R.M.G.B. Rajanayake Dr. W.G. Piyal AriyanandaProf. Sudantha Liyanage Ms. M.N. WithanageMs. G. M. Fonseka Dr. M. SirimuthuMr. Susil Kathriarachchi Mr. Sulith LiyanageMr. Subodha Hemathilaka

Co opted MembersMr. S. Perasiriyan Dr. M.P. DeeyamullaDr. Poshitha Premarathne Mr. Viraj JayalathMr. Ayal Perera Mr. Thisath AlahakoonMr. Wasantha Samarakoon

3. Activities• Contributions to Activities of the Institute of

Chemistry Ceylon (a) Full page advertisement of “Chemistry in Sri

Lanka”. (b) Contribution for the Interschool Chemistry

Quiz (c)Award for the Best Performance at the

Graduateship Examination in Chemistry Levels 3/4 Theory Examination

• All - Island Inter School Chemistry Essay

Competition.• Inter University Chemistry Essay Competition• Book donation programme• A/L Teacher training workshop• Advanced Level Chemistry Seminar• ndustrial Visit for B.Sc. Special degree students,

M.Sc. students and RSC Members• Collaboration with SLAAS E-2 workshop and

seminars• Supporting Chemical Societies of Universities in

Sri Lanka

Mrs. Aruni Wickramanayake Hony Secretary

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chemistry · chemistry (or chemical sciences) acceptable to the council are entitled to the...

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