Use of Sugar Beet Flour and Wheat Bran as Carbon Source Improves the Efficiency of Chrysoporthe cubensis Enzymes in Sugarcane Bagasse Saccharification

High cost and low efficiency of lignocellulolytic enzymes are the main challenges that must be overcome to make second-generation ethanol more competitive in the fuel market. The cultivation of microorganisms using different agro-industrial wastes as substrates is one of the alternatives to reduce the process costs and obtain more efficient enzyme cocktails in the biomass hydrolysis. Since the fungus Chrysoporthe cubensis has proved to be a promising source of lignocellulolytic enzymes from wheat bran, this study aimed to evaluate the effect of different lignocellulosic materials in its enzyme production and the effectiveness of a new enzymatic cocktail on sugarcane bagasse saccharification. Primarily, this fungus was grown under solid-state fermentation, using wheat bran, elephant grass, or sugarcane bagasse as carbon sources. Afterwards, the wheat bran was combined with sugar beet flour in different ratios, and both were used as carbon sources. The enzymatic profiles were investigated and the most promising enzyme extract was applied to pretreated sugarcane bagasse saccharification. A new cocktail obtained from the combination of wheat bran and sugar beet flour in ratio 1:1 showed the highest activity for almost all enzymes tested and was more efficient than extract obtained with only wheat bran, especially in saccharification of alkaline pretreated sugarcane bagasse, releasing 18 g.L −1 of glucose and 14.8 g.L −1 of xylose, which correspond to 38.5% of cellulose and 61.6% of hemicellulose, respectively. Therefore, the combination of both substrates is an effective strategy to induce Chrysoporthe cubensis to produce a complex and efficient enzymatic cocktail in the biomass hydrolysis.