CELLULASES PRODUCTION AND OPTIMIZATION IN THERMOBIFIDA FUSCA

Abstract

Cellulases are the third largest Industrial Enzymes because of their importance in paper recycling, detergent enzymes and as animal feed additives. It is very likely that the cellulases will become the major Industrial enzymes, if bioethanol produced from biomass turns into a main transportation fuel. The recalcitrant structure of cellulose prevents the proper degradation of biomass into monomeric sugars. Cellulase enzymes are responsible for the bioconversion of lignocellulosic biomass into soluble sugars which can further be converted into ethanol. Among cellulolytic microbes, Thermobifida fusca possesses great physiological and cellulolytic characteristics i.e thermostability, high activity and tolerance to high pH range. Secreted cellulases are obtained from Thermobifida fusca under bioreactor condition and by giving different substrate concentrations of avicel (cellulose) i.e 0.5 %, 1 % and 2 % to Thermobifida fusca for cellulase production. After cellulase production the activity of crude and concentrated cellulases were checked and compared on different cellulosic substrate i.e avicel, carboxymethyl cellulose and cellobiose for determining exoglucanase, endoglucanase and β-glucosidase activity respectively. Enzyme activity assays were performed on both crude and concentrated cellulases. The cellulase activity of Thermobifida fusca was compared with the already available commercial cellulases of Trichoderma reesei and Aspergillus niger. Higher β-glucosidase activity of 1.57 IU/ml and endoglucanase activity of 1.43 IU/ml were obtained from Thermobifida fusca cellulases as compared to the activity of other two commercial cellulases which makes it a potent enzyme to be used as an important cellulose degradation material.