Recent advancements in various steps of ethanol, butanol, and isobutanol productions from woody materials

Chemical Engineering Department, Lakehead University, Thunder Bay, ON, Canada, P7B5E1. .
Biotechnology Progress (Impact Factor: 1.88). 01/2013; 29(2). DOI: 10.1002/btpr.1688
Source: PubMed

ABSTRACT In this review, the recent advancements and technical challenges associated with the production of ethanol, butanol and isobutanol via bioconversion routes from celluloses of woody materials are reviewed. Physicochemical processes, e.g. steam explosion, seem to be the most viableprocessfor pretreating woody materials. Although enzymatic hydrolysis is selective, it is rather a slow process. Acid hydrolysis is a relatively fast process with a high yield, but it produces inhibitory compounds of fermentation, which necessitates a detoxification process prior to the fermentation. Presently, the major challenges in the production of ethanol,butanol and isobutanol via biological conversions are the ratherlow production yield and the sensitivity of microorganisms to the presence of inhibitors and productsin fermentation media. In this study, the recent advancements in the applications of S. cerevisiae,C. Acetobutylicum and C. glutamicumas, the most promising microorganisms, for ethanol, butanol and isobutanol production arealso discussed. © 2013 American Institute of Chemical Engineers Biotechnol. Prog., 2013.

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