Simultaneous saccharification and fermentation of steam exploded wheat straw pretreated with alkaline peroxide

Abstract

The cellulose content of substrate is one of the most important factors for ethanol production from lignocellulose. To increase the cellulose content of substrate and ethanol yield in simultaneous saccharification and fermentation (SSF), a pretreatment method coupling steam explosion with alkaline peroxide for wheat straw was studied. After the complex pretreatment, the cellulose content in wheat straw increased from 31.5% to 67.2%. In the hydrolysate of wheat straw pretreated with the complex method and steam explosion, the glucose concentration was 110.9 g/L and 67.8 g/L, respectively. The optimal conditions for SSF were 40 °C, 120 h, cellulase loading 40 FPU/(g wheat straw), yeast inoculum 10% (v/v) and substrate concentration 16.7% (w/v). Under the optimal conditions, the total ethanol concentration in SSF of wheat straw pretreated with steam explosion and alkaline peroxide reached 51.5 g/L, and an overall yield of 81.1% was obtained.