Sugar cane bagasse pretreatment: An attempt to enhance the production potential of cellulases by Humicola insolens TAS-13

Abstract

Pretreatment of the cellulosic substrate has miracle effect on the enhancement of cellulase production by fungal strains. A thermophilic strain of Humicola insolens TAS-13 was locally isolated and was tested for cellulases production under solid-state fermentation conditions using sugar cane bagasse as substrate. The cultural conditions for the H. insolens were also optimized for the higher rate of cellulase secretion. In order to enhance the production rate of heterogenous
cellulosic proteins, bagasse was pretreated with NaOH, H2SO4, H2O2 and H2O2+1.5%NaOH. The pretreatment of bagasse with 2.0% H2O2 along with 1.5% NaOH enhanced the biosynthesis of cellulases by H. insolens. Production rate was also optimized with different parameters like thickness of fermentation medium, initial pH, incubation time and temperature. The thickness of the fermentation medium of 0.8 cm (10 g) with pH range of 5.5 was found to be better for enhanced production at 50°C. The yield of the enzyme was reached maximum with CMC-ase (18.98 U/g/min), FP-ase (13.63 U/g/min), -glucosidase (19.54 U/g/min) 72 h after inoculation.