Improved ethanol and reduced xylitol production from glucose and xylose mixtures by the mutant strain of Candida shehatae ATCC 22984

Appl Biochem Biotechnol. 2012 Apr;166(7):1781-90. doi: 10.1007/s12010-012-9586-y. Epub 2012 Feb 11.

Abstract

A mutant Cs3512, which showed better fermentation of xylose and the mixtures of xylose and glucose, was obtained through mutation of Candida shehatae ATCC 22984 and screening with a medium containing antimycin A and TTC (2,3,5-triphenyltetrazolium chloride). Cs3512 produced 44.4 g/l of ethanol from 121.3 g/l of xylose, which was 13% higher than that by ATCC 22984. At the same time, xylitol production was reduced by 38% to 10.2 g/l from 16.3 g/l by ATCC 22984. Cs3512 also showed 8% increase in ethanol yield from 0.39 to 0.42 g/g comparing to ATCC 22984 when fermenting the sugar mixture composed of 52.9 g/l glucose and 21.2 g/l xylose. When Cs3512 was used in the simultaneous saccharification and fermentation of lime pretreated rice straw via CaCCO (calcium capturing by carbonation) process, it produced ethanol at 77% of the theoretical yield. The results imply that Cs3512 is a potential non-recombinant yeast strain for ethanol production from lignocellulosic biomass.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Antimycin A / pharmacology
  • Biomass
  • Bioreactors
  • Calcium Compounds / chemistry
  • Candida / drug effects
  • Candida / genetics
  • Candida / metabolism*
  • Ethanol / metabolism*
  • Fermentation
  • Glucose / metabolism*
  • Lignin / metabolism*
  • Organisms, Genetically Modified
  • Oryza / chemistry
  • Oxides / chemistry
  • Tetrazolium Salts / pharmacology
  • Xylitol / biosynthesis
  • Xylose / metabolism*

Substances

  • Calcium Compounds
  • Oxides
  • Tetrazolium Salts
  • lignocellulose
  • Ethanol
  • Antimycin A
  • triphenyltetrazolium
  • Lignin
  • Xylose
  • lime
  • Glucose
  • Xylitol