Biochemical characterization of thermostable cellulase enzyme from mesophilic strains of actinomycete

Abstract

A few mesophilic strains of actinomycete were used for detection, extraction and characterization of cellulase enzymes. These strains responded to produce all the three components of cellulase complex (endoglucanase, exoglucanase and â-glucosidase) in balanced quantities. Cellulase activity was determined on solid medium supplemented with 1% carboxy methyl cellulose (CMC). Production of cellulase was detected by the formation of clear or transparent zone around colonies. The greater size of transparent zone has been found proportional to the higher capabilities of the strains for enzymes. The extraction of cellulase enzyme was done in liquid basal medium. The assay of cellulase was observed by measuring the release of reducing sugar (RS) by DNS method. All the three components of cellulase viz. endoglucanase, exoglucanase and â -glucosidase were assayed in terms of CMCase, FPase and cellobiase, respectively and expressed in International units (IU). These strains were further tested for their ability to produce cellulase complex enzyme by growing on a defined substrates as well as on delignified cellulosics. The optimization for â-glucosidase enzyme was carried out by studying the various parameters viz. effect of pH, incubation period and nitrogen sources.

Key words: Cellulase, actinomycete, optimization, reducing sugar, carboxy methyl cellulose.