Fermentation of pretreated corncob hemicellulose hydrolysate to ethanol by Candida shehatae and Saccharomyces cerevisiae

Abstract

To investigate the effect of unknown fermentation inhibitors in corncob hemicellulose acid hydrolysate processed by pretreatment and detoxification on fermentation, corncob hemicellulose acid hydrolysate and artificially prepared hydrolysate were fermented in parallel by Candida shehatae YHFK-2. The results show that fermentability of corncob hemicellulose acid hydrolysate was better than that of the artificially prepared hydrolysate and scale-up of C. shehatae YHFK-2 fermentation was done, which showed that ethanol production in the fermenter was obviously much more than that in flasks. In addition, C. shehatae YHFK-2 and Saccharomyces cerevisiae W5 were used for mixed fermentation of corncob hemicellulose acid hydrolysate, which was done for exploring the possibility of efficiently increasing ethanol production.

Key words: Ethanol, corncob hemicellulose acid hydrolysate, fermentation property, stability, mixed fermentation.