Synthesis of Bacterial Polysaccharides as a Limiting Factor for Biofuel Production
K. Geetha, K. N. Rajnish, J. Rajendhran and P. Gunasekaran
from: Bacterial Polysaccharides: Current Innovations and Future Trends (Edited by: Matthias Ullrich). Caister Academic Press, U.K. (2009)
Bio-ethanol has been considered as a potential alternative energy source to the conventional petroleum based fuel. Zymomonas mobilis is an efficient ethanol producing bacterium and it is advantageous over Saccharomyces cerevisiae with respect to ethanol productivity and tolerance. Z. mobilis possesses nearly 100% theoretical ethanol conversion rate on glucose-based media, while it has only about 70% theoretical yield from sucrose. The reduced ethanol yield has been attributed to the formation of by-products such as levan, fructooligosaccharides and sorbitol. The efficiency of ethanol production by Z. mobilis from sucrose-based substrates can be improved by limiting the formation of by-products either by optimizing the fermentation conditions or genetic improvements of Z. mobilis . Recent strategies developed for the improved production of ethanol, while limiting the formation of levan and the vice versa are discussed read more ...