Evaluation of co-culture system to produce ethanol and electricity from wheat straw hydrolysate using Saccharomyces cerevisiae and Pichia fermentans.

Lignocellulosic biomass holds a potential to be used in the production of biofuels and bioelectricity, as an economic and eco-friendly substrate. The production of bioethanol and bioelectricity was evaluated in a microbial electrochemical reactor using wheat straw hydrolysate. Wood degrading white-rot fungi, Phlebiafloridensis, was used to prepare wheat straw hydrolysate. An efficient bioconversion of sugars present in wheat straw hydrolysate into ethanol and electricity has been demonstrated to achieve a cost-effective and net-zero emissions goal using co-cultures of yeasts. The fermentation was performed in a single vessel electrochemical bioreactor using Saccharomyces cerevisiae and Pichia fermentans. Both the yeasts were allowed to ferment WS hydrolysate up to 15 days as pure or co-culture. Co-culture of yeasts showed electrochemical response in terms of maximum power density (77.5 mW m⁻²) using WS hydrolysate. Maximum ethanol production of 8.7% (w/v) was observed on the 5th day. Thus, the results of this study validate the use of biological integrated approach like microbial electrochemical reactor to produce ethanol and electricity from wheat straw hydrolysate. [ABSTRACT FROM AUTHOR]