The optimization of nutritional factors and their concentrations for the amylase production by Bacillus cereus MCM B-326 in submerged fermentation was carried out using response surface methodology (RSM) based on the central composite design (CCD). The design contains a total of 20 experimental trials containing starch, soybean meal and CaCO3 as model factors for three levels. The mutual interaction between these variables resulted into 1.36 fold increase in amylase activity as compared to the mean predicted response at zero level of all variables. Amylase from B. cereus has approximate molecular weight of 40 kDa with optimum activity at pH 7.0 and temperature 30░C.
Production of amylase under submerged fermentation Bacillus sp. was investigated using wheat bran, soybean meal and CaCO3 (WSC) medium. Response surface methodology (RSM) was used to evaluate the effect of the main variables, i.e., pH (11.35), temperature (35.16░C) and inoculum size (2.95%) on amylase production by applying a full factorial central composite design (CCD). The mutual interaction between these variables resulted into 4.64 fold increase in amylase activity as compared to the non-optimized environmental factors in the basal medium.
Glucoamylase is a well recognized amylolytic enzyme used in food industry, which is generally produced by Aspergillus genus under solid-state fermentation (SSF). This study presents production of glucoamylase by Aspergillus oryzae on the solid surface of rice husk, wheat bran, rice bran, cotton seed powder, corn steep solids, bagasse powder, coconut oil cake, and groundnut oil cake as substrates. Optimization of the SSF media and parameters resulted in a 24% increase in the glucoamylase activity. Optimum glucoamylase production (1986 Ámoles of glucose produced per minute per gram of dry fermented substrate) was observed on wheat bran supplemented with 1%, (w/w) starch, 0.25%, (w/w) urea at pH 6, 100%, (v/w) initial moisture and 300C after incubation 120 hrs. Therefore, A. oryzae can be useful in bioprocessing application for saccharification of agro-residues.