Enhanced cellulase production by Penicillium oxalicum for bio-ethanol application

•A potent cellulolytic fungal strain was isolated and identified as P. oxalicum.•Media engineering enhanced cellulase production by 1.7-fold.•In bioreactor incubation time was reduced for producing same cellulase titer.•In-house cellulase showed equal hydrolysis potential as that of commercial ones. Present study was focused on cellulase production from an indigenously isolated filamentous fungal strain, identified as Penicillium oxalicum. Initially, cellulase production under submerged fermentation in shake flasks resulted in cellulase activity of 0.7FPU/mL. Optimization of process parameters enhanced cellulase production by 1.7-fold and resulted in maximum cellulase activity of 1.2FPU/mL in 8days. Cellulase production was successfully scaled-up to 7L fermenter under controlled conditions and incubation time was reduced from 8days to 4days for achieving similar cellulase titer. Optimum pH and temperature for activity of the crude enzyme were pH 5 and 50°C, respectively. At 50°C the produced cellulase retained approximately 50% and 26% of its activity at 48h and 72h, respectively. Hydrolytic efficiency of P. oxalicum was comparable to commercial cellulase preparations which indicate its great potential for application in the lignocellulose hydrolysis.