Isolation, Identification and Cellulase Production by two Bacillus Species from the Soil under Dipterocarpus and Lagerstroemia Forests

摘要

Cellulase producing bacteria were isolated from two forest soils of Dipterocarpus (Local name Garjon) and Lagerstroemia (Local name Jarul) and were identified to be Bacillus sphaericus (GK1) and Bacillus pumilus (JK1) respectively. Optimization of the fermentation medium for maximum cellulase production was carried out with respect to the culture conditions at pH, temperature, incubation period, substrate concentrations, carbon sources and nitrogen sources. The isolate GK1 showed highest enzyme production after 4 days at pH 6.5 besides the isolate JK1 showed highest enzyme production at 35-C of 1% substrate concentration. Maximum cellulase production was showed by isolate GK1 when asparagine was used as nitrogen source while isolate JK1 showed highest cellulase production using CMC as carbon source. The isolate GK1showed highest CMCase activity using at 40-C, 1.5h optimum incubation period and 1% CMC as substrate concentration and the isolate JK1 showed highest CMCase activity at pH 7.5. In comparative activities of different cellulases the crude enzymes of the isolate JK1 showed highest enzyme activities i. e. CMCase 185.59 U/ml.