Enzymatic Hydrolysis of Sugarcane Bagasse Using Enzyme Extract and Whole Solid-state Fermentation Medium of Two Newly Isolated Strains of Aspergillus Oryzae

Abstract

Enzymatic conversion of lignocellulosic biomass into fuels and chemicals will be a key technology in the future. However, in order to make this process economically feasible, it is necessary to improve the efficiency of enzyme production, since the cost of the enzymatic cocktails significantly influences the viability of the overall process. In this sense, the use of solid-state fermentation (SSF) is particularly advantageous for enzyme production. Here, a comparative study on the enzymatic hydrolysis of steam- exploded sugarcane bagasse (SESB) using enzymatic extract (EE) and whole solid-state fermentation medium (WM) of two newly isolated strains of Aspergillus oryzae (P6B2 and P27C3A) from the Amazon Rainforest was carried out. The biomass conversion using WM from A. oryzae P6B2 was more efficient when compared with the EE, while for A. oryzae P27C3A the conversion yields were similar. The WM from P27C3A supplemented with a low dosage of commercial enzyme resulted in a final conversion of 45% of the theoretical value. Furthermore, the combination of the enzymes from both strains, allowed up to 5 folds improvement in SESB conversion. These results showed that the in-house enzyme production by wild-typeoryzae strains cultivated under SSF can be very advantageous for the enzymatic hydrolysis of biomass and, thus, it can be considered as a potential biotechnological configuration for the production of biofuels.