Evaluation of different biological and chemical treatments in agroindustrial residues for the production of fungal glucanases and xylanases

Abstract

The production and use of fibrolytic enzyme complex in the hydrolysis of lignocellulosic materials is an important strategy for renewable bioenergy. The different carbon sources (residues) with or without some pretreatments (biological or chemical) were analyzed in order to increase the production of fibrolytic enzyme. Glycosyl hydrolases and xylanases were produced using Trichoderma reesei QM9414. The influence of some crude or pre-treated agro-industrial residues as a carbon source was previously investigated using shake-flask cultures. Subsequently, the selection of the best culture medium was studied under different pH and temperature conditions in stirred tank bioreactor. Fibrolytic activities reached a maximum of 0.85 ± 0.07 FPU mL−1 (total cellulase), 3.14 ± 0.01 CMC mL−1 (endoglucanase) and 1.25 ± 0.14 U mL−1 (exoglucanase) with the orange peel residue; and 93.08 ± 3.27 U mL−1 (xylanase) with sugarcane bagasse under alkali pretreatment. In the stirred tank bioreactor the cellulolytic activity increased to 1.76 ± 0.00 FPU mL−1, about 2 times higher than in the shake-flasks or under studied conditions. The biosynthesis of the fibrolytic complex using agroindustrial residues supplemented was shown to reach a higher total cellulose production.