Produção e caracterização de celulases e hemicelulases obtidas por cultivo de fungos mesófilos em resíduos agroindustriais

Abstract

The enzyme production using agroindustrial wastes by solid state fermentation (SSF) and the study of their physicochemical properties are of undoubted importance to improve the performance of saccharification processes and increase economic viability of 2G ethanol. Among them, β-glycosidases and β-xylosidases are essentials for the good hydrolytic efficiency by acting on oligosaccharides from celullose and hemicelullose despolymerizations from previous kinds of celullases and hemicellulases. Thus, this work produced and quantified hemi- and celullolytic complex enzymes (β-xylosidase, xylanase, β-glycosidase, avicelase, CMCase and FPase), by SSF using Pleurotus ostreatus PLO6 isolated and in consortium with Aspergillus niger SCBM1. Then, the optimal conditions and stability against pH and temperature variations were determined for β-glycosidase and β-xylosidase. The activity spikes of β-glycosidase, β-xylosidase, FPase, xylanase, avicelase and CMCase were 2.95, 0.54, 3.72, 4.15, 7.86 and 4.95 U/g, respectively, for P. ostreatus isolated and 98.51, 62.92, 3.77, 12.40, 13.37 e 20.19 U/g when on consortium with A. niger. β-glycosidase was highlighted with peak of production on fifth day (98.518 U/g) of fungal growth, optimum pH of 4.0 and optimal temperature of 45 °C. β-xylosidase was the second highest production, with peak of production on fourteenth day (62.92 U/g), optimum pH of 3.5 and optimal temperature of 55 °C. Both enzymes were stable in acid pH range (3.0 to 7.0) and β-xylosidase showed thermostability up to 55 °C. The presented data indicated that the enzymatic extract produced by consortium demonstrated suitable characteristics for future industrial applications in biomass saccharification processes.