Production of cellulases and β-glucosidases by Trichoderma reesei Rut C30 using steam-pretreated sugarcane bagasse: an integrated approach for onsite enzyme production

Abstract

The high cost of commercial cellulases still hampers the economic competitiveness of the production of fuels and chemicals from lignocellulosic biomasses. This cost may be decreased by the on-site production of cellulases with the integrated use of the lignocellulosic biomass as carbon source. This integrated approach was evaluated in the present study whereby steam-pretreated sugarcane bagasse (SPSB) was used as carbon source for the production of cellulases by Trichoderma reesei Rut C30. The use of SPSB resulted in an enzyme preparation with a cellulase activity of 1.93 FPU/mL. Additionally, a significant β-glucosidase activity, of 0.37 BGU/mL, was achieved in buffered media, which is not a common feature of T. reesei culture supernatants, indicating the importance of pH control during enzyme production. The hydrolysis of SPSB with the laboratory-made mixture resulted in a glucose yield of 80%, which was equivalent to those observed for control experiments using commercial enzymes. It was shown that SPSB is a promising carbon source for the production of cellulases and β-glucosidases by T. reesei Rut C30 and that the enzyme preparation obtained is effective for the hydrolysis of SPSB without the need for β-glucosidases supplementation, supporting the on-site integrated approach to decrease the cost of the enzymatic hydrolysis of lignocellulosic biomass.