Monday, April 19, 2010
LL Conference Facility (Hilton Clearwater Beach)
In order to obtain economical feasibility of biofuel production including biobutanol, biomass is one of most important factors. Ceylon Moss is red algae, and it is able to be harvested by 5-6 times a year. Ceylon Moss has a much easier saccharification step compared to lignocellulosic biomass owing to low lignin content. Ceylon Moss Saccharified Liquid (CMSL) has galactose (20 g/L) as main carbohydrate component. CMSL was used to produce butanol using solventogenic clostridia such as Clostridium acetobutyricum ATCC824, Cl. beijerlinkii NCIMB8052, Cl tetanomorphum ATCC49273 and Cl. aurantobutyricum NCIMB10659. Solventogenic clostridia have a branched pathway, and strains produce different fermentation products in change of growth conditions because of carbon and electron flux changes. It was known that lactate was not used as a sole carbon source by Cl. acetobutylicum. However, Cl. acetobutylicum can use lactate with acetate, increasing butyrate production because lactate oxidation to pyruvate can be coupled with the reduction of crotonyl-CoA to butyryl-CoA. Solventogenic clostridia were cultivated on the modified Reinforced Clostridia Medium (RCM) with CMSL (50%) instead of glucose and starch. Cl. acetobutylicum and Cl. aurnatibutyricum could use more galactose in CMSL. These two strains were cultivated on the modified RCM with CMSL (50%) with different concentration of acetate, lactate, and butyrate. Butanol production was different according to concentration of these organic acids. Our results indicated that solventogenic clostridia could utilize CMSL as carbon and energy sources, and lactate with acetate can influence butanol production during fermentation.
(Supported by Ministry of Knowledge Economy in Korea, 2008-N-BI08-P-01)
(Supported by Ministry of Knowledge Economy in Korea, 2008-N-BI08-P-01)