Produção de celulases e hemicelulases por cultivo em estado sólido de linhagem fúngica termófila isolada do cerrado sul-mato-grossense

Abstract

The microbiological cultivation processes have conquered a prominent place in biotechnological development, showing operational and economic characteristics in the use of enzymes, as in the reduction of costs on an industrial scale. The difficulties in decompose cellulosic biomass in glucose can be converted into value-added products, has become the cellulases and hemicellulases one of the most studied enzyme systems currently. Thus, the use of alternative substrates, such as agroindustrial residues, is of great importance for reducing the cost of production of these enzymes. In countries as Brazil, the agroindustrial residues represent an important alternative source for production of microbial enzymes, due to the large amount of nutrients available, so these can be used as low-cost raw materials for solid state cultivation processes (CES) that deserve to be highlighted in the use of these by-products, besides being beneficial to the environment. Thus, the objective of this work was to evaluate the production of cellulolytic and hemicellulolytic enzymes using different agroindustrial substrates by solid state cultivation of a thermophilic fungal lineage (isolate 23), isolated from the Cerrado south-mato-grossense. The production of the enzymes was obtained by cultivation of the micro-organism in wheat bran containing 70% humidity, at the temperature of 40° C, where the biggest production of cellulases (CMCase and β- glucosidase) was 30,9 U/g to 72 hours of culture and 229,7 U/g in 120 hours, and hemicellulases (xylanase and β-xylosidase) was 179,5 U/g to 48 hours of culture and 12,6 U/g in 96 hours. The results allow concluding that the micro-organism isolated has potential for its industrial application, mainly for presenting characteristics relevant to theproduction of cellulolytic and hemicellulolytic enzymes in low added value culture media.