Advances in biobutanol production by clostridia with designed biomass, lactic acid and butyric acid

摘要

@@Biobutanol, one of the valuable biofuels, is produced by acetone-butanol-ethanol (ABE)-producing clostridia through fermentation. Compared with the traditional biofuel ethanol, butanol has a lot of advantages because it shows non-hygroscopicity and low vapor pressure and can be used in any concentration with gasoline (1). In recent years, fermentative butanol production has drawn much attention, and there have been increasing studies on butanol production using many types of carbon sources. Most of studies focus on mono-, oligo-, or polysaccharides such as glucose, sucrose, lactose, xylose, xylan, and starch, derived from various biomass. On the other hand, some organic acids are known to stimulate ABE production and to be produced through other fermentative processes with designed biomass (2), which we can arbitrarily design as optimal substrates in accordance with the targeting bioprocess by selecting or modifying its characteristics. Because ABE-producing clostridia have the several pathways for utilizing organic acids such as lactic acid and butyric acid, these organic acids have great potential as substrates in the production of butanol. Here, we describe our studies on advances in butanol production using lactic acid or butyric acid as a substrate.