Abstract
Cold activeenzymes along with their producing microbes are of commercial value and find multiple applications in various industrial and biotechnological sectors. In this study, production optimization of cold active a-amylase from cold-adapted Microbacteriurn foliorum GA2 was carried out. The aim of the present work was to use economical agro-substrate for increasing cold-active ix-amylase production and to optimize the fermentation parameters in SSF (Solid state fermentation) using two statistical experimental designs. Plackett-Burman design and response surface methodology was used to determine key ingredients for the best media composition and optimal concentration of these components, respectively. The screening result of Plackett-Burman design showed bagasse, lactose and pH had significant effects (p-value' 0.05) on cold-active a-amylase production. Maximum cc amylase production (6610 units) was observed through response surface methodology in medium having 40% bagasse, 0.003 M lactose, and pH 8.0 at 20 degrees C when incubated for 5 days in static conditions. The closeness of optimized values (R-2=92.26%) to experimental values (R-2=96.28%) proved the validity of the statistical model. Under these experimental designs, the a-amylase yield increased three-fold in comparison to control and was much efficient and economical than "one-variable at a time" methodology. Thus, cold-adapted M. foliorum GA2 could be exploited for industrial production of a-amylase using bagasse at relatively low temperatures.(C) 2013 Elsevier Ltd. All rights reserved.