Macro-micro fungal cultures synergy for innovative cellulase enzymes production and biomass structural analyses

Abstract

Biofuels are a sustainable and cost-effective alternative to existing transportation fuels. Currently a combination of chemical and enzymatic degradation of lignocellulosic biomass to fermentable sugars has been pursued despite economic challenges. In this study, we have critically investigated individual and synergistic combination of Asperigillus oryzae (Ahlburg) E. Cohn. and Pycnoporus sanguineus (L.) Murrill for production of cellulases from groundnut shell (GNS) using solid state fermentation (SSF). Since these combinations of innovative co-fungal systems mimic nature-inspired bioconversion, we anticipate optimum ligno-cellulolytic enzymes production with the right mix of appropriate enzymes. We have evaluated and selected fungal cultures showing rapid radial growth using ImageJ software, followed by SSF studies. SSF of GNS hydrolysate was carried out at room temperature in stationary flasks. Under co-culture conditions, maximum enzyme hydrolysis was observed with cellulase release on the 4th day at 112.4 FPU/ml, endo-glucanase on the 6th day at 174.8 IU/ml and β-glucosidase on the 10th day at 75.7 IU/ml. Spectral and thermal characterization combined with imaging techniques revealed a reduction in the rigidity of the hydrolysate, enabled novel understanding of the effect of fungal growth on biomass and has opened the door for economic bioethanol production with the use of microbes-fortified biomass.