Türk Biyokimya Dergisi (Sep 2006)
Enhanced Production and Extracellular Activity of Commercially Important Amylolytic Enzyme by a Newly Isolated Strain of Bacillus. sp. AS-1
Abstract
Studies on the optimum conditions for the production of α-amylase were carried outwith a newly isolated bacterial strain of bacillus sp.AS-1. The optimum temperaturefor amylase production was detected as 35°C. α -Amylase production occurred atpH 5.0-9.0 with a maximum at pH 7.0. The optimal pH and temperature values forextracellular activity were 7.5 and 50°C respectively. Effect of different salts werenoted and it was found that CaCl2 with concentration of 0.2g/l played an importantrole for optimum production and stability of alpha amylase in the fermentationmedium. Starch with a concentration of 20 g/l was a good source for the enzymesynthesis. The levels of the α-amylase production detected in culture supernatantsvaried greatly with the type of carbon source used. Lactose, soluble starch andglucose stimulated α-amylase production. Effect of different nitrogen sourcesrevealed that peptone increase the enzyme yield. The concentration of yeast extractwas an important factor for the α-amylase synthesis by the isolate. The activity ofthe enzyme increased between 2 and 4 g/l yeast extract concentrations with anoptimum of 4 g/l. The optimal concentration of peptone for the production of α-amylase was detected as 10g/l.
