<I>T. reesei</I>及び低胞子性<I>A. tubingensis</I>のカクテル酵素を用いたタケパルプからの同時糖化発酵によるエタノール生産

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 KRCF700-33Y and Trichoderma reesei ATCC66587, and thermotolerant yeast (Saccharomyces cerevisiae BA-11) under simultaneous saccharification and fermentation (SSF) at 40°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.