Statistical modeling and optimization of cellulase production by Bacillus licheniformis NCIM 5556 isolated from the hot spring, Maharashtra, India

Cellulase shows great interest in the field of organic acids, and biotechnology industries. Cellulase-producing thermophilic bacteria was isolated from West Coast hot spring (Rajapur, Ratnagiri District of Maharashtra (Lat. 16°38′42″N; long. 73°31′53″E) and identified as Bacillus licheniformis. Out of seven variables in the cellulase production medium, four variables such as carboxy methyl cellulose (CMC), calcium chloride, Tween-20, and temperature were screened through Plackett-Burman design and further optimized through response surface methodology (RSM) for higher cellulase production. The optimal conditions were found to be CMC, 19.21 g/L, CaCl2·6H2O, 25.06 mg/L, Tween-20, 2.96 mL/L and temperature 43.35 °C. The high cellulase production 42.99 IU/mL was achieved in a 7 L scale bio fermenter using optimal conditions. A 3 fold increase in cellulase production was achieved by RSM model. These methods have proven suitable to optimize cellulase production by a thermophilic Bacillus.