Abstract

A fermentation organism capable of producing a high fermentation yield in the presence of inhibitors, necessary for the realization of increased efficiency in the process of production of second-generation bioethanol from inedible plant biomass, has been developed. The construction of the organism involved a combination of mutagenesis and selection and self-cloning, and results indicated the effectiveness of this combination in the creation of fermentation organisms. Self-cloning is a form of genetic modification implemented within a scope that makes it possible to treat the organism as non-genetically-modified.Mutagenesis and selection using biomass hydrolysates increased both the organism’s tolerance to inhibitors in hydrolysates and its ethanol fermentation yield. Using the selected strain as a base, genes for the expression of transaldolase and alcohol dehydrogenase were enhanced by self-cloning. The developed strain was able to produce a higher concentration of ethanol.An examination of the entire process led to the discovery of a biomass pre-treatment condition that would control the production of phenols, which act as inhibitors. A process using this pre-treatment condition and the developed fermentation organism would be able to produce 213 L of ethanol from 1 dry-ton of corn stover.

References

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Author (organization or company)

• Yoshiki TSUCHIDA（Fundamental Technology Research Center）
• Norihiko TSUKAGOSHI（Fundamental Technology Research Center）

Publication Information

Article of Honda R&D Technical Review Vol.28 No.2 (108 - 116)

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Citation Information