Optimization of process parameters for -amylase production under solid-state fermentation by Bacillus Cereus MTCC 10202

Abstract

An alpha amylase producing fungal strain was isolated from spoiled food and identified as Aspergillus awamori. Production of extracellular alpha-amylase by Aspergillus awamori was studied in solid-state fermentation. Twelve different agro-residues such as wheat bran, maize bran, corn bran, millet bran, rice bran, green gram bran, black gram bran, cassava peel powder, cotton seed oil cake, coconut oil cake, sesame oil cake and groundnut oil cake were screened for alpha-amylase production using Aspergillus awamori MTCC 9997. Among them, cassava peel powder was found to be the best substrate for alpha-amylase production. The physical and chemical parameters that influence the production were optimized. Maximum alpha-amylase production was obtained at pH 6 after 96h of fermentation at 40 degrees C. An inoculum level of 10% (volume per mass) was found to be optimum for alpha-amylase production. Among different carbon and nitrogen sources supplemented, starch and beef extract at 2% concentration enhanced alpha-amylase production considerably. Calcium chloride at a concentration of 0.8 % was found to stimulate alpha-amylase production.