Optimization of cellulase production by Albifimbria verrucaria TRQ88 and its application in saccharification of cellulose pulp from wheat straw.

Cellulases have attracted considerable attention in the scientific community due to their potential applications in biofuel production and the generation of high-value products. The cellulase enzymatic system mainly comprises three enzymes: endoglucanase, exoglucanase, and β-glucosidase, which act synergistically to degrade cellulose in lignocellulosic materials such as pulp and wheat straw. Fungus Albifimbria verrucaria is an endophytic strain isolated in the Yaqui Valley, Mexico, with potential for cellulase production and enzymatic index potential. This study aimed to maximize cellulase production from Albifimbria verrucaria using response surface methodology with a central composite design to degrade wheat straw cellulose pulp. The variables evaluated during submerged fermentation, temperature, initial pH, and fermentation time, were used to maximize cellulase enzyme production. Statistical analysis indicated that the quadratic model explains cellulase production, reaching 2.33 U/ml for total cellulase activity (FPase) and 2.25 U/ml for endoglucanase activity (CMCase), corresponding to 1.77-fold and 1.28-fold increases under optimized conditions, respectively. Finally, enzymatic hydrolysis of wheat straw cellulose pulp using the crude enzymatic extract was carried out for 72 h, yielding 0.057 g of glucose per gram of substrate, demonstrating the potential of the fungus for lignocellulosic biomass conversion to bioenergy.