Amylase production by moderately halophilic Bacillus cereus in solid state fermentation

Abstract

The production of extracellular amylase by the moderately halophilic bacterium Bacillus cereus was studied in solid state fermentation (SSF). Solid substrates such as rice bran, wheat bran, sugarcane bagasse, black gram husk and green gram husk were studied for enzyme production. Growth on sugarcane bagasse gave the highest amylase activity. The time course for amylase production inferred that 48 h was the optimum duration for higher amylase production. The suitable pH, temperature and inoculum level observed for higher amylase production was pH 7.0, 40.0°C and 2.0%, respectively. The amylase production ofB. cereus was high in maltose (carbon source), yeast extract (nitrogen source), Tween 80 (surfactant) and calcium chloride (metal ion) added medium when compared to other respective sources tested. The halotolerancy of B. cereus for amylase production was 3% sodium chloride. The sugarcane bagasse can be utilized for the cheap production of amylase from Bacillus cereus. It is less expensive in comparison to synthetic media and is readily available for production purposes. Key words: Bacillus cereus, amylase, solid state fermentation (SSF), sugarcane bagasse.