Thermochemical pretreatment of corn husk and enzymatic hydrolysis using mixture of different cellulases

Abstract

The present study compared dilute acid and alkaline pretreatment of corn husk. It showed that maximum reducing sugar production was obtained when biomass was pretreated using dilute sodium hydroxide. Further, effectiveness of dilute alkaline pretreatment was evaluated through Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), scanning electron microscopy (SEM), and biochemical composition study. Batch enzymatic hydrolysis of dilute alkaline pretreated biomass was carried out using several combinations of different cellulases (Trichoderma, Fusarium, and Aspergillus). Maximum reducing sugar production was obtained when pretreated biomass was hydrolyzed using mixture of Trichoderma, Fusarium, and Aspergillus cellulases. Further, batch enzymatic hydrolysis process was optimized using CCD (central composite design)-based RSM (response surface methodology). In addition, using mixture of different cellulases, batch and fed-batch enzymatic hydrolysis processes were compared. It showed that 14.34-mg/mL higher reducing sugar production was obtained in the case of fed-batch process compared to batch process.