Optimized production, purification and characterization of alpha amylase by Brevibacterium linens DSM 20158, using bio-statistical approach

Abstract

Various cultivation parameters were optimized using a statistical approach to improve the alpha amylase yield by Brevibacterium linens DSM 20158. The Plackett-Burman design was used to screen the fermentation variables followed by the optimization of five significant parameters by response surface central composite design (CCD). The optimum levels for maximum production of enzyme were moisture level (82.5%), inoculum size (4.30%), wheat bran (14.2 g), temperature (33.5°C) and (NH 4) 2SO 4 (0.4 g). Alpha amylase yield was found to be twofold higher than that obtained in the unoptimized reference medium. The closeness of optimized values to experimental values proved the validity of the statistical model. The enzyme was purified 7.88-fold with a 16.80% yield, and it appeared homogeneous on SDS PAGE with a molecular weight of 58 kDa. © Springer-Verlag and the University of Milan 2011.