Produção de celulases por fermentação semissólida em bagaço de pedúnculo do caju utilizando Trichoderma reesei LCB 48.

Abstract

Cellulases, among many enzymes, have been highlighted in several activities niche, such as food, detergents, pharmaceuticals, textiles, pulp and paper and wastewater treatment of effluents and residues. Currently, most commercially used microbial cellulases are produced by the species Trichoderma, in particular, Trichoderma reesei with proven ability for the production of cellulolytic enzymes. Studies have been developed in order to produce this enzyme through a process of solid state fermentation from lignocellulosic agroindustrial wastes, thus reducing the cost of enzyme production, and adding value to the residue. The aim of this work was to produce cellulases from the stalk of the cashew bagasse using Trichoderma reesei LCB 48. Characterizations were carried out aiming at the residue of the chemical composition of the pulp relative to the cashew nutrients, since it was used as substrate for the fermentative process for production of cellulase. The study of the production of cellulase was performed using the 2 factorial design with central point in quadruplicate. The stalk of the cashew bagasse washed inoculated with T. reesei was evaluated for the production of cellulases with initial moisture contents of 45, 55 and 65% and in the presence of inorganic nitrogen (ammonium sulfate) at concentrations 0.5, 0.75 and 1%. The fermentation was developed over 238 hours during which the parameters analyzed were pH, moisture, AR and enzyme activity expressed in CMCase. Through the characterization of the waste bagasse from the stalk of the cashew confirm that this substrate has the potential to be used in fermentation for production of cellulolytic enzymes, mainly because it presented a satisfactory percentage of cellulose, for that is known to be an excellent inducer of these enzymes. Peak production of cellulase enzyme expressed in CMCase was achieved with 238 hours this being with a value of 0.71 U/g (0,095 U/mL), under the conditions of 45% initial moisture content and 1% of nitrogen source. Using the methodology of experimental design allowed us to observe that the initial substrate moisture is a key variable in the production of enzymes CMCases, and that the minimum level of humidity (45%) showed the highest production values of CMCase.