fac.ksu.edu.safac.ksu.edu.sa/.../default/files/322_phg_handout_20121.docx · web view322 phg lab....
TRANSCRIPT
King Saud UniversityPharmacy College
Pharmacognosy Department
322PHGPractical course
TA/ Hanan AL- Ati & Ghadah AL-Hmoud
PHG
322
322 PHG Lab. syllabus: (2nd. semester 1432/1433)
SubjectsDateLab#
Introduction of alkaloid + Assay of Nicotine
13,15,16/3/14331
Assay of Reserpine 20,22,23/3/14332
Assay of Tropane Alkaloids(Strychnine in Nux vomica)
27,29,30/3/1433
3
Qualitative Identification of Alkaloids (part I)
4,6,7/4/14334
Qualitative Identification of Alkaloids (part II)
11,13,14/4/14335
Microscopical analysis of powder drugs containing Alkaloids + revision
18/20/21/4/14336
Practical Exam + Quiz25,27,28/4/14337
Introduction of glycosides +Assay of senna
9,11,12/5/14338
Assay of Cardiac Glycosides 16,18,19/5/1433
9
UV Spectrum of Flavanoid 23,25,26/5/1433
10
Qualitative Identification of Glycoside
1,3,4/6/143311
Microscopical analysis of powder drugs containing glycosides
8,10,11/6/143312
Revision15,17,18/6/143313
Practical Exam + Quiz22,24,25/6/143314
Safety:
Porcelain dish
Round bottom flask
Lab#1
PHG
322
Drug abuse(Assay of
nicotine in urine.)
Pharmacognosy Department
Drug abuse:Drug abuse is related to taking
a psychoactive drug or performance enhancing drug for a non-therapeutic or non-medical effect.
Abuse drug can be classified according to it's effect on CNS into:1. CNS depressants
a. Narcotic analgesics (Opioid): e.g. Morphine
b. Sedatives and hypnotics: e.g. Barbiturates
2. CNS stimulants
a. Caffeine and nicotine
b. Cocaine
3. Hallucinogens
a. LSD
Nicotine.• Nicotine, is a liquid alkaloid which exists chiefly as
malate in the leaves of Nicotiana tabacum.
• In low concentrations (an average cigarette yields about 1 mg of absorbed nicotine).
• Nicotine first stimulates nerve cells and then paralyses them.
• The primary therapeutic use of nicotine is in treating nicotine dependence in order to eliminate smoking (gums, dermal patches and lozenges).
AlkaloidsWhat is an ALK.?
Is nitrogenous comp. having complex molecular structure and significant pharmacological activity, most of them is basic in nature, most from plants.
Assay of Nicotine in urine.
Principle:
Procedure:
nicotine
r blu
Crimsom green to
blue
E.P=
Calculation:
Lab#2
PHG
322
Assay of Reserpine.
Structure: Indole alkaloids.
Uses: As hypotensive agent
Procedure:
Assay of Reserpine.
Pharmacognosy Department
Comments on the assay : 1-Citric a`inc. the solubility of reserpine & prevents its hydrolysis.
2-Reserpine could be extracted from acidic medium by CHCl₃ since it is weak base.
3-Sod. Hydrogen carbonate is used to remove excess a`.
6- H₂SO₄+sod. nitrite Nitrous a` which react e` the alkaloid & give the yellow colour.
7- Sulfomic a` is used to decompose excess nitrous a`.
Lab# Student name: ID:
E.P=
Calculation:
Lab#3
PHG
322
Assay of liq. Extract of Nux
Nux vomica: - bitter-tasting drug obtained from the poisonous seeds of Strychnos nux-vomica.
- The dried seeds contain strychnine and brucine, both colorless crystalline alkaloids, as well as sugar, acid, and oil.
-I n the past nux vomica was used as a tonic in the form of a tincture, or alcoholic solution, but it is not used in modern medicine. - In minute quantities it has a powerful peristaltic action on the intestines and in larger doses causes convulsions and death.
Principle:
Pharmacognosy Department
Procedure )3 steps(:
(1) Purification:
(2) Alkalinization:
Red blue
pipette
(3) Extraction:
Comments on the assay: 1) To insure that the alka. Is in salt form.
2) To remove impurities.
3) To remove any volatile bases & the CHCl₃ remain.
4) To dissolve any resonance from the alkaloid bec. it will decrease the reading.
PHG
322 Qualitative Identification of
Alkaloids(part I&II)
Pharmacognosy Department
Chemical test for qualtitive identification of Alk. :
3 (Marqui’s reagent:Formaldehyde+ conc. H₂SO₄
Specific Alk. colour reactions.
1)Ephedrine:
2)Brucine:
3)Strychnine:
)20%(NaOH
u
Lines radiating from crystals
4)Atropine:
5) Papaverine:
ORANGE/RED
Fades rapidely
6) Caffeine:
7) Quinine:
BROWN PPT.
Brown ppt.
Scheme for Unkown AlK. Sol.
emerald
Lab#6
PHG
322Microscopical analysis of powdered drugs containing alkaloids
A( Belladonna leaves:
• Microscopical examination:a) Idioblast
containing crystals of Ca Oxalate (Microsphenoidalcrystals)
b) Glandular hair (multicellular stalk
Pharmacognosy Department
Atropa belladonna
& unicellular heads)
c) Anisocytic Stomata
• Active constituents: 1- Hyoscyamine, hyoscine & atropine2- Volatile base.
• Uses: act as local anesthetic & as sedative to relieve spasmodic cough.
B( Datura leaves:
Alkaloids
Datura stramonium
• Microscopical examination:a) Crystal layer
of Cluster crystal of Ca Oxalate
b) Non Glandular hair(multicellular,unicerate)
c) Anisocytic Stomata
d) Glandular hair (unicellular stalk & multicellular head)
• Active constituents: 1- Contain mainly hyoscyamine & hyoscine Atropine may be formed
from racemisation of hyoscyamine
• Uses:1- In motion sickness due to sedative action of hyoscine.2- Dilate the eye pupil due to atropine presence.
C( Hyoscyamus leaves:
• Microscopical examination:a) Ca Oxalate
(Twin prism)
Alkaloids
Green
Hyoscyamus niger
b) Branched Hair (Glandular hair)
c) Anisocytic Stomata
• Active constituents: 1-Hyoscyamine,hyoscine & atropine.
• Uses:Relieve the spasm, as sedative & in insomnia.
D( Cinchona bark:
Alkaloids
Cinchona succirubra
Rubiaceae
• Microscopical examination:a) Phloem fibers
e`funnel shaped lumen
b) Parenchyma cells containing Ca oxalate
c) Starch granules
d) Cork cell
• Active constituents: 1- Quinine2- Quinidine3- Cinchonine4- Cinchonidine
• Uses:Stomachic, antimalarial due to the presence of quinine.
Alkaloids combined with tannin (cinchotannic acid)
• Chemical tests:
Cinchona pd. Red fume
E( Ipecacuanha root:
• Microscopical examination:a) Acicular
crystals of Ca oxalate
b) scleride
c) Starch granules
d) Cork cells
flame
Cephaelis ipecacuanha
• Active constituents: 1- Isoquinoline alkaloids: emetine, cephaline
• Uses:1- expectorant and emetic2- ameobic dysentry due to presence of emetine
Lab#7
PHG
322
1St. Practical Exam.
Pharmacognosy Department
Lab# 8
PHG
322
Assay of Senna
Pharmacognosy Department
Glycosides
What are Glycosides?They are gp. of plant constituents which upon hydrolysis yield sugar & non sugar parts.
Glycosides
sugar part )glycone( Non sugar part )aglycone(
stability & solubility pharmacological activity
Link b/t sugar & non sugar part gives the following types of glycosides :
C-glycoside
O-glycoside
N-glycoside
S-glycoside
e.g, Senna leaf
Function in the plant:
1- Energy producer during seedlings through hydrolysis of steroid compounds.
2- Detoxifying agents for many harmful substances that are transferred to the barks, seed coats & fruits in the form of glycosides.
3- Attractive substance.4- Protective against microorganism & insects.
10
10-
10-10-
Classification of glycosides :
1) According to the chemical nature of aglycone:
e.g. Senna anthraquinone glycoside. Steroid steroidal glycoside.
2) According to the active constituents:
e.g.Cyanogenetic glycosides containing (HCN) e.g.Amygdaline.
3) According to the therapeutic activity:
e.g.Cardiac glycosides e.g.Digitalis.
4) According to the plant origin:
e.g.salicin from Salix species.
Types of glycosides :
1( Primary glycosides:The unchanged form of glycoside which occur naturally in the fresh plant & not the product of any stage of hydrolysis of a glycoside.
2( secondary glycosides: Result from the hydrolysis of 1ry glycosides,usually by (enzymatic,acidic & alkaline) activity e.g. of enzymes: Emulsin enz. & Myrosin enz.
Examples of glycosides:
1- Phenolic glycoside. e.g. Salicin2- Anthraquinone glycoside. e.g. Senna, Aloe…….etc3- Cardiac glycoside. e.g. Digitalis.4- Flavonoid glycoside. e.g.Rutin5- Tannin.e.g. Tea & gall.6- Saponins. e.g.Quillaia bark.
Assay of Senna
Senna
Free anthraquinone. Combined anthraquinone.
Sennidin (aglycone) Sennosides (glycoside)
Main anthracin in Senna is4 types of sennoside (A,B,C,D).A=optically active (levo rotatry) B=Optically inactive (meso rotatry)A&B both have COOH. C & D both have CH2OH.
Glycoside = Soluble in polar organic solvents. Aglycone = Soluble in Organic solvents insol.in In H2O.
Sugar = Soluble in H2O insol. in organic solvents .
Principle :
Procedure:
On W.B.
Shake
Rose red colour
PHG
322
Pharmacognosy Department
Spectrophotometric assay of cardiac glycoside in Digoxin By 4 methods:
1) Xanthydrol method.
2) Digoxin reagent method.
3) Baljet reagent method (Picric a`:NaOH).
4) Kedd`s reagent method (dinitrobenzoic a`: NaOH)
Note:
1) Method no.(1&2) are used to determin the deoxy sugar part while (3&4) are used for aglycon part.
2) These methods are stability indicated in the solid form. Bec. solids are more stable than liquids. since in sol. form aglycone results from hydrolysis during storage w`may effect in abs. e`sugar present in glycoside.
So what we can do? (principle)
Procedure: )U.S.P method )
Importance of U.V. spectrum of flavonoids:
PHG
322U.V. spectrum of flavonoids
Pharmacognosy Department
1(For determination of unknown by compression e`standard.
2(For determination of no. & position of OH gp. by specific reagents.
Structure of Flavonoids:
Note:Cinnamoyl part have U.V. abs. higher than benzoyl part bec. It has conjugations w`make resonance that make high abs.
e`MeOH: Flavone (aglycone) = BandI (304-346)
(glycoside) Flavonol (aglycone) = Band I (352-385) (glycoside) = Band I (346-365)
Shift reagents:
The use of shift reagents for identification of free OH in flavones & flavonols.
A-BandI:1( NaOMe: -(sp.for 4´-OH) . - give bathochromic shift)40-60nm(.
-make ionization for OH gp & make conjugation.
2( AlCl3:
3( Boric a`)H3BO3(: orthodihydroxy system e`OH at C3`,C4`or C4`,C5` or both (a`labaile) (bathochromic shift in band I )12-35nm(.
B) BandII: 4( Na acetate:
OH at C7 (bathochromic shift in bandI I) )5-20nm(.
Interpret the spectrum data and draw the structure of the compound.
Compound (A): (Molish , s test -ve)
MeOH 240, 366 MeOH +NaOMe 236, 420
MeOH +AlCl3 290, 401 MeOH +AlCl3 + HCl 291, 401 MeOH +NaOAc 266, 320
MeOH +NaOAc +H3BO3 208, 364
Interpret the following data and draw the structure of the compound.
EXCERSISES
Compound (A), Molish,s test +ve
Yellow compounds show the following UV. Spectral data : (λmax (nm))
Compound NO. (1): (Molish , s test –ve)
MeOH: 252, 307NaOMe: 237, 380AlCl3 290, 394AlCl3 + HCl: 291, 394NaOAc: 266, 400NaOAc +H3BO3: 208,300
Compound NO. (2): (Molish , s test –ve) MeOH: 247, 341NaOMe: 293, 400AlCl3: 258, 380AlCl3 + HCl: 247, 341NaOAc: 277, 400NaOAc +H3BO3: 257,365
Interpret the above spectral data and draw the structure of the compounds.
Lab#11
Examples of glycosides:
PHG
322
Qualitative Identification of
Glycosides
Pharmacognosy Department
1(Phenolic glycosides:
2 )Anthraquinone glycosides: )senna leaves(
( water extract )
b)Aloe (alc. extract)
3(Cardiac glycosides: )Digitalis pd.( )alc.ext.(
Cardiac glycosides
Cardenolides )5-membered ring( Bufadienolides )6-membered ring(
d) Lieberman-Burchard test(specific for steroid nucleus):
purple
Orange-red
Cardenolides
4(Flavonoids glycosides: )Rutin( ) alc.ext.(
5( Tannins: )H2O. extract(
6(Saponins: )Quillaia bark, liquorice root(
Effervescence & evolution of red fumes
Lab#12
PHG
322
Microscopical analysis of
powdered drugs containing
Pharmacognosy Department
1( Senna Leaves:
• Microscopical examination:a) Paracytic
stomata
b) Ca Oxalate: Crystal Sheath
c)Simple hair (unicellular uniglandular hair covered by warty cuticle)
• Active constituents:1- Sennosides A,B,C&D 2- Aloe-emodin & rhein in small amount.
• Uses: As purgatives especially in cases of habitual constipation, in small dose, it is used as laxative.
2(Digitalis leaves:
• Microscopical examination:a) Collapsed hair
(multicellular,non glandular)
b) Unicellular stalk, Multicellular head)
Anthraquinone glycosides.
(multicellular stalk,unicellular head)
a-From below,b-from the side,c-fromabove
c) Anomocytic Stomata
• Active constituents: 1-Purpurea glycosides A & B.
2-Hydrolytic enzyme & oxidase which form secondary glycosides (digitoxin & gitoxin)
• Uses:As cardiotonic in most forms of cardiac failure.
3( Squill bulb:
Primary glycosides.
• Microscopical examination:a) Raphides
crystals of Ca Oxalate (bundle,free,broken)
b) Epidermal cell
• Active constituents: - crystalline glycosides scillaren A
- an amorphous mixture scillaren B
• Uses:heart tonic, in small doses as expectorant but in large doses as emetic.
Cardiac glycoside
4( liquorice root:
• Microscopical examination:a) Starch
granules
b) Ca oxalate (prisms)
c) Fibres with in complete Ca oxalate prism sheath
• Active constituents: a- sweet principle glycyrrhizinb- flavonoids (liquiritin, isoliquiritin)
c- coumarin
• Uses:1- mild expectorant
2- gastric ulcer
3- rheumatoid arthritis
• Chemical test : 1- powdered liquorice + 1-2 dps of H2SO4 orange color
2- Shake with water permanent froth (10-15 min.)
Lab#13
PHG
322
Revision
Lab#14
PHG
322
Final Practical Exam
Pharmacognosy Department
Pharmacognosy Department