Effect of alkaline treatments at various temperatures on cellulase and biomass production using submerged sugarcane bagasse fermentation with Trichoderma reesei QM 9414

Abstract

Trichoderma reesei QM 9414 was cultured to produce cellulase and biomass using as substrates untreated bagasse (non-alkali-treated bagasse washed with distilled water), and bagasse alkali-treated at room temperature and at 100°C, washed with water at pH 2. Avicel (microcrystalline cellulose) was used as a control substrate. When untreated bagasse and bagasse alkali-treated at room temperature were used, appreciable cellulase activity was found (0.085 and 0.090 IU/ml, respectively), but activity was lower than when Avicel was used (0.163 IU/ml). Enzyme yields were 16, 19 and 22 IU/g cellulose consumed, respectively. Cellulase activity was not detected when bagasse alkali-treated at 100°C was used. The biomass yield was about 30% lower when bagasse was used as a substrate than when Avicel was used. The yield was higher when bagasse was alkali-treated than when untreated bagasse was used, although the difference was small. The biomass yield was 0.78 g biomass per g cellulose consumed for alkali-treated bagasse at room temperature versus 0.50 g/g for bagasse alkali-treated at 100°C, 0.57 g/g for untreated bagasse and 0.67 g/g for Avicel. It was concluded that untreated bagasse is as good a substrate for cellulase and biomass production as bagasse alkali-treated at room temperature.