Bioethanol production by enzymatic hydrolysis from Aspergillus calidoustus employing different lignocellulosic wastes

Abstract

Cellulolytic enzymes were necessary for the decomposing of forest waste cellulose present in the environment. Based on the molecular characterization, the N6.2 potent cellulolytic fungal isolate was identified as determined Aspergillus calidoustus. The physical parameters of 5 days of incubation at 30 °C with seven pH resulted in high yield of cellulase enzymes. The endoglucanase activity was determined 87.36 U/ml, followed by β-glucosidase activity of 43.11 U/ml and exoglucanase, 21.03 U/ml under optimized conditions. Treatment of cellulosic substrate Pongamia and wood wastes by Aspergillus calidoustus resulted in breakdown of ligocellulosic waste with exoglucanase activity 234.50 ± 2.13 & 125.00 ± 2.50 U/ml, followed by endoglucanase activity 208.55 ± 4.03 & 112.08 ± 1.51 U/ml and β-glucosidase of around 90.57 ± 0.72 & 54.71 ± 2.50 U/ml. Further, the fermentation of pre-treated cellulosic polymer broth resulted in the production of bioethanol production of around 4.4 g/l/g of Pongamia leaves waste and 2.2 g/l/g of wood waste by the action of Saccaharomycetes spp. Hence, the current work outlines the cellulosic substrates utilization for sustainable two-step bioethanol synthesis, and potential implications for extensive research.