Production of Alkaline Protease from Bacillus licheniformis through Statistical Optimization of Growth Media by Response Surface Methodology

An alkaline protease producing bacterial strain Bacillus licheniformis (MTCC NO. 7053), which was obtained from IMTECH, Chandigarh used for protease production studies. Three significant variables effecting protease production like rice husk (variable 1); inoculum size (variable 2); KNO3 (variable 3) have been identified under preliminary optimization studies. These variables are selected for alkaline protease production in current study. By using these eloquent variables, the basal media was subjected to statistical optimization using response surface methodology. The superlative growth media components and bacterial growth conditions for ultimate protease production were as follows: rice husk (3%); inoculum size (2%); KNO3 (0.75%); salt solution, 5% (v/v)-{(MgSO4.7H2O, 0.5% (w/v); KH2PO4 0.5% (w/v)}; and FeSO4.7H2O, 0.01% (w/v) at 37°C and 160 rpm for 72 h production. The alakaline protease activity was notably increased with statistically optimized medium (185.4 ± 0.23 U/ml) when compared to unoptimized basal medium (132 ± 0.76 U/ml). This shows that model was satisfactory and also indicates the adequacy of the model.