Production and Optimization Parameters of Amylases from Bacillus subtilis RSKK96 Under Solid State Fermentation

Abstract

The production of extracellular a-amylase by producing Bacillus subtilis RSKK96 was studied under solid state fermentation (SSF). Various agroresidues as substrate were studied for enzyme production. The highest enzyme yield was expressed with cotton stalk substrate (1016.3 +/- 32.6 U g(-1) . 10(-3)). Production parameters were optimized as incubation time 72 hours, incubation temperature 37 degrees C, agitation speed 150 rpm, inoculum size 35 %, initial moisture content 30 %, initial pH 7.0. Supplementation of the fermentation medium with carbon and metal salt sources decreased the enzyme production. Among different nitrogen sources supplemented, ammonium nitrate (1 %) showed maximum enzyme production (1483.1 +/- 32.5 U g(-1) . 10(-3)). Enzyme activity was observed as 73 % at 100 degrees C.