Production of cellulases by solid state fermentation using natural and pretreated sugarcane bagasse with different fungi

Lignocellulosic biomass is an important source of energy and it has been extensively studied in the production of second generation ethanol. For this purpose, the complex lignocellulosic matrix must be deconstructed by thermal or chemical pretreatment, followed by cellulose depolymerization using cellulolytic enzymes to release simple fermentable sugars. This process still has several techno-economical drawbacks, such as the cost of enzymes. Aiming to reduce the cost of theses enzymes, their production have been studied by solid-state fermentation (SSF) using low-cost agroindustrial residues as carbon source to the microbial growth. In this context, this work aimed at studying the operational conditions (temperature and moisture content) for the production of cellulases from the fungi Penicillium sp., Rhizomucor sp. and Trichoderma koningii INCQS 40331 (CFAM 422), utilizing natural sugarcane bagasse (NSB) and pretreated by acid-alkaline solution (AAB) and hydrogen peroxide (HPB) as substrates. The study was performed by using three-level factorial design (32) with central points. The results showed that the more suitable fungus for cellulases production was the Trichoderma koningii (8.2 IU/g substrate), followed by Penicillum sp (1.7 IU/g substrate). Moreover, the best results were obtained using NSB for all fungi. Statistical analyses showed that the temperature has a greater effect on the production of cellulases by the evaluated fungi.