PRODUCTION, PURIFICATION AND CHARACTERIZATION OF CELLULASES FROM WILD AND MUTANT STRAINS OF ASPERGILLUS SPECIES

Microbes are ubiquitous tiny organisms/biomachines which have enormous potential to \ud produce many kind of industrially important products (enzymes, metabolites, phenolics, \ud antibiotics etc) when feeding upon specific medium. This study is about the exploration \ud of native aspergillus members for the production of cellulase enzyme and to get enhanced \ud production through mutation. \ud All the isolates assessed for the production ability of CMCase (carboxymethyl cellulase) \ud and taxonomically identified as A.niveus, A. fumigatus, A.versicolor, A. niger, A. wentti, \ud A. terreus, A. nidulance, A.flavus. Optimized medium for selected Aspergillus versicolor \ud (Gen Bank Accession KF905652) was 0.5% CMC, 4 pH, 0.075% peptone, 0.1% tween \ud 80, 1.5% NaNO3, 0.05% CaCl2 at 120 hrs and 30°C. CMCase purified by 40% \ud ammonium sulfate followed by gel permeation chromatography with 11 folds of \ud purification and molecular weight was 59 kDaltons. Km and Vmax determined as 1.134 \ud mg/ml and 1435 U/ml/minute. CMCase maximum reactivity attained by 50mM Citrate \ud Phosphate buffer, 0.5% CMC, pH 4 and 30°C for 30minutes.Storage stability at -18°C, \ud 4°C and 25°C retained 69%, 44% and 12% activities at 25th day respectively. \ud KIBGE-IB37MT was a mutant of Aspergillus versicolor (KIBGE-IB37) the optimum \ud medium was 0.5% CMC, pH 4, 0.1% peptone, 0.1% Tween 80, 120 hrs and 30°C. \ud CMCase purified up to 12.26 folds with 59 kDaltons molecular weight. CMCase maxima \ud obtained by 25mM Citrate Phosphate buffer at 30°C for 30 minutes while Km and Vmax \ud were 1.13 mg/ml and 1435 U/ml/minute respectively. Shelf life at -18°C, 4°C and 25°C \ud was estimated as the retention of 70, 63 and 49 % activities respectively