Porous inert material as promising carrier enhanced cellulase production from Trichoderma reesei in solid-state fermentation

Abstract

Developing a promising fermentation strategy with high cellulase yield and stable fermenting performance is an imperative way to overcome the cellulase costs limitation. In this study, a novel solid-state fermentation (SSF) strategy using polyurethane carbon foams (PAF) as inert carriers was developed to improve cellulase production by Trichoderma reesei (T. reesei). The effects of significant process parameters such as pore size and thickness of carrier on cellulase production were evaluated. Repeated cycle fermentation using inert carrier for cellulase production was assessed by measuring cellulase activity. Results indicated that inert carrier was conducive to cellulase production and the higher cellulase activity of 0.368 FPU/mL was achieved in SSF with PAF rather than PPF or PUF. More cellulase components could be obtained from SSF with inert carrier compared with submerged fermentation. In addition, higher cellulase activity (0.393 FPU/mL) could be achieved at 0.6 mm pore and 15 mm thickness of PAF. The repeated cycle fermentation experiments showed that maximum cellulase activity of 0.514 FPU/mL was obtained over 6 cycles and the fermentation performance was still stable in SSF with PAF. Therefore, SSF using inert carrier is simple, low cost, and environmentally benign, making it an attractive method for cellulase production.