Ethanol Production from Bamboo Pulp under Simultaneous Saccharification and Fermentation Using a Cocktail Enzyme of T. reesei and Sporeless Strain of A. tubingensis

Abstract

Bamboo is an attractive biomass resource which grows rapidly, reaching their maximum size within a few months. Bamboo pulp, prepared by soda-anthraquinone cooking, was fermented to ethanol with a cocktail enzyme of Aspergillus tubingensis KRCF7OO-33Y and Trichoderma reesei ATCC66587, and thermotolerant yeast (Saccharomyces cerevisiae BA-11) under simultaneous saccharification and fermentation (SSF) at 4O°C. The strain A. tubingensis KRCF700-33Y, having sporeless, high β-glucosidase productive capacity was generated by UV irradiation. The highest activity of 5 FPU/ml was obtained with a cocktail enzyme having a 10% content of A. tubingensis, and the cocktail effect was also shown under the SSF process. An ethanol concentration of 47.1 g/ L was achieved using a cocktail enzyme (15% content of A tubingensis) with a substrate loading level of 15% under small scale SSF, which resulted in an ethanol yield of 76.8% after 96 h. An ethanol concentration of bamboo pulp reached 44.0 g/L under SSF process using a reactor (1-L kneader) with a cocktail enzyme (10% content of A. tubingensis, 4 FPU/g-DM), which resulted in an ethanol yield of 71.8% after 144 h. The results indicated the feasibility of bioethanol production from bamboo pulp under SSF using on-site produced enzyme by solid-state fermentation.