Investigation of organic wastes from Mediterranean plants to produce biogas by anaerobic digestion
Post on 01-Feb-2017
New Biotechnology Volume 31S July 2014 ENVIRONMENTAL BIOTECHNOLOGY
Effects on TomatoGrowth and Soil Bacterial Communityby Application of Arthrobacter woluwensis ED Immobi-lized in Alginate Beads
Hong-Gyu Song , Seung-Tak Kwon
Kangwon National University
For the promotion of plant growth and increase of persistenceof plant growth promoting rhizobacteria (PGPR) in rhizpsphere,tomato growth was examined after application of PGPR Arthrobac-ter woluwensis ED immobilized in alginate bead. When tomatoseedlings were treated with A. woluwensis ED of 1106 cells gsoil1 and incubated for 30 days in a plant growth chamber,shoot and root length, fresh weight and dry weight of the growntomato plants treated with the suspended inoculants significantlyincreased by 36.2, 59, 51.1 and 37.5%, respectively comparedto the uninoculated control. The treatment of the immobilizedbacteria increased those by 42, 67.4, 62.5 and 60.4%, respectivelycompared to the uninoculated control. Therefore, the enhance-ment of tomato growth by the treatment of the immobilizedbacteria was higher than those by the suspended inoculants. Theeffects of the inoculation on soil bacterial community and the fateof the inoculated bacteria were monitored by DGGE analysis. TheDNA band intensity of A. woluwensis ED in the tomato rhizospheretreated with the suspended inoculants continuously decreasedafter inoculation, but the band intensity in the tomato rhizospheresoils treated with the immobilized inoculants showed the max-imum at 1 week after inoculation and the decreasing rate wasless than that of the suspended inoculants, which indicated thelonger maintenance of the immobilized bacteria at rhizosphere.Therefore, encapsulation of PGPR in alginate beads may be moreeffective than liquid inoculant for the plant growth promotionand survival of PGPR at plant rhizosphere.
Bioremediation of heavy metal contaminated soil usingplant extract as biomaterial
In-Hyun Nam , Chul-Min Chon, Jae-Gon Kim
Korea Institute of Geoscience and Mineral Resources (KIGAM)
An indigenous plant extract was used to produce calcite fromCanavalia ensiformis as effective biomaterial, and its ability toform under stable conditions was compared to that of purifiedurease. X-ray diffraction and scanning electron microscopy wereemployed to elucidate the mechanism of calcite formation fromthe crude plant extracts. The results revealed that urease in theplant extracts catalyzed the hydrolysis of urea in liquid state cul-tures and decreased heavy metal amounts in the contaminatedsoil. The heavymetal amounts were decreased in the leachate fromthe treated mine soil; 55.4% of Pb, 35.6% of Cu, 33.6% of Mn,32.0%of As, and 25.6%of Fe, respectively. The procedure describedherein is a simple and beneficial method of calcite biomineraliza-
tion without cultivation of microorganisms or further purificationof crude extracts. This study suggests that crude plant extractsof Canavalia ensiformis have the potential to be used in place ofpurified forms of the enzyme during remediation of heavy metalcontaminated soil. Thus, we report the molecular characterizationof the microbial diversity and composition change of the mineimpacted soil or waste ore taken from the site during bioremedi-ation processes are presented. To evaluate the stability of DGGEpatterns in remediated mine soils in comparison with before orafter plant extract treatment, a number of soil samples with timeinterval in the mine impacted soil were compared using PCR-DGGE of 16S rDNA.
Investigation of organic wastes from Mediterraneanplants to produce biogas by anaerobic digestion
Camille Menard , Anais Fantoni, Pascale Bradesi, Eric Leoni,Dominique Cancellieri
Universite de Corse
The University of Corsica is contributing to the research ofboth efficiency and integration of renewable energy in the mainelectrical grid. Since 2013, a scientific program concerning thevalorization of biomass energy has been developed to investigatethe methane potential through the anaerobic digestion processof lignocellulosic resources. In Corsica, due to the clearing brushpolicy to prevent forest fires, cellulosic wastes are generated.Besides, Corsica is an important producer of essential oil fromMediterranean species thanks to a process generating an importantamount of dried vegetation as waste every year.
The aim of this preliminary study on biomass as renewableenergy was to characterize and to select the most appropriatesubstrates for the anaerobic digestion process. Fiber contents andBiochemical Methane Potential (BMP) were performed on fivesubstrates. Heather, rockrose and strawberry tree were chosen asrepresentative of forest fuels. Water distillation residues of laureland immortelle were considered as natural resource wastes.
On this work, we focus on the three species which had thebest BMP. Rockrose, dry residue of immortelle and strawberry treeproduced 139, 124 and 87Nm3 CH4 per grams of volatile solids,respectively. The ratio holocellulose: lignin, thanks to the VanSoest method of fiber determination, was determined for thosespecies: 3.8, 3.4 and 1.7. This parameter is a key factor to takeinto account for the correlation of the BMP with the composi-tional characteristics. Further work will be performed on thesechosen substrates to optimize the anaerobic digestion process in15L-reactors.