초록
B. licheniformis AT70 which produced a thermophilic, raw-starch degrading alpha-amylase was isolated from Gorooh hot springs in Kerman province. Maximum production of AT70 alpha-amylase was obtained in the presence of starch (as a carbon source) and ammonium chloride (as a nitrogen source) with 388 and 329U/ml enzyme yield, respectively. SSF was also carried out using various agricultural and kitchen wastes and results showed that the maximum yield of AT70 alpha-amylase production was obtained by date waste and wheat bran, respectively (10%, w/v). The thermal stability of the AT70 alpha-amylase was increased about 2.5 folds at 60<SUP>o</SUP>C. AT70 alpha-amylase showed the maximum activity at 1.5M NaCl by 42% and local detergent Shooma enhanced the alpha-amylase activity about 34%, compared to control. Furthermore, AT70 alpha-amylase exhibited remarkable hydrolytic activity in a range of 14-20% (w/v) of raw corn starch at 55<SUP>o</SUP>C. These results indicated that AT70 alpha-amylase has great potential applications for the raw-starch degrading.