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Updated: Aug 14, 2026

Techniques for the Evolution of Robust Pentose-fermenting Yeast for Bioconversion of Lignocellulose to Ethanol
Published on: October 24, 2016
[Conditions for forming ethanol during bioconversion of cellulose-containing raw material]
N V Ziabreva1, E P Isakova, V V Biriukov
1State Research Institute of Protein Biosynthesis, Moscow, 109004 Russia.
Abstract:
Several natural associations composed by thermophilic anaerobic bacteria capable of utilizing various cellulose materials at 60 +/- 2 degrees C and pH 6.0-7.0 were isolated from the sludge of Kamchatka geothermal springs. The rate of ethanol production (up to 1.7 g/l per day) and the concentration of ethanol in the medium (up to 1.2%), as well as the fermentation period (10-15 days) were determined under anaerobic conditions in the presence of cellulose, coniferous sawdust, newsprint, or paper pulp as a carbon source. Microorganisms were found that inhibited the production of ethanol. The initial pH value was found to influence both the ethanol production rate and ethanol/acetate ratio. A pH decrease from 7.0 to 5.0 led to 6.7-fold increased the ethanol production and caused a 23.8-fold increase in the ethanol/acetate ratio.
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