Optimization of critical process parameters for amylase production by Bacillus sp. using statistical approach (RSM)

Abstract

The aim of this work was to optimize the process parameters through the statistical approach for the production of alpha amylase by Bacillus sp. in submerged fermentation (SMF). Initially critical physical and chemical process parameters influencing the enzyme production were identified by Plackett-Burman method ( eleven variables, seven nutritional, two physical and two dummies) were analyzed. Then optimum levels of most influencing parameters affecting amylase production were obtained by CCD and results were analyzed by standard analysis of variance (ANOVA). The effect of interaction of physiochemical parameters on the amylase production (z axis) was studied by plotting three dimensional response surface curves against any two independent variables. A high similarity was observed between the predicted and experimental results, which reflected the accuracy and applicability of RSM to optimize the process for enzyme production. As a result of RSM the optimum values for starch concentration -0.65%, (NH 4 ) 2 SO 4 -0.55% and pH- 8.33. As a result of media optimization, a titre of 1, 22,000 U/L -1 was achieved. A total of 2.4 fold increase in enzyme activity was observed.