ISOLATION, IDENTIFICATION, AND MEDIA OPTIMIZATION OF HIGH-LEVEL CELLULASE PRODUCTION BY Bacillus sp. BCCS A3, IN A FERMENTATION SYSTEM USING RESPONSE SURFACE METHODOLOGY

摘要

Cellulases are important glycosyl hydrolase enzymes, which break down cellulose to b-glucose. They have been used widely in biotechnological processing such as bioethanol production. In this work we studied maximizing cellulase production by Bacillus sp. BCCS A3 using response surface methodology (RSM). A good result was attained with these conditions (% w=v): tryptone 0.1, Na_2PO_4 0.25, (NH_4)_2SO_4 0.2,MgSO_4 ? 7H_2O0.005, CaCl_2 0.005, KH_2PO_4 0.1, NaCl 0.1, sodiumcarboxymethylcellulose (CMC) 0.75, and pH 9. The cellulase activity in optimized medium was 49.80U=ml. Moreover, high level of enzyme production was obtained by using fermentor system (50.30U=ml). Thus, according to the obtained results, this statistical method provided quick identification and integration of key medium details for Bacillus sp. BCCS A3, leading to more cellulase production.