Simultaneous saccharification and fermentation of pretreated sugarcane bagasse to ethanol using a new thermotolerant yeast

Abstract

Enzymatic hydrolysis of a cellulosic substrate is the most critical step for the production of bioethanol. In our study, the hydrolysis of steam-exploded sugarcane bagasse (SESB) under optimized conditions (8 % substrate consistency, 22.5 U filter paper cellulase, 0.55 % Tween 80) released a maximum of 461 mg per gram dry substrate sugars. We isolated a thermotolerant yeast strain, Blastobotrys adeninivorans RCKP 2012, from sugarcane bagasse collected from the Cooperative Sugar Mill, Sonepat, Haryana that was found to be capable of fermenting the enzymatic hydrolysate of SESB at 50 °C. When grown under simultaneous saccharification and fermentation conditions, this yeast produced 14.05 g L−1 ethanol, which corresponds to a theoretical ethanol yield of 46.87 %.