Study on properties of α-amylase from Aspergillus oryzae 1228.

The properties of α-amylase produced by Aspergillus oryzae 1228 were studied.The results showed that when in fermentation medium there were 20% soybean cake and 2% NaCl,with initial pH 6.6,in 3% inoculating size,at 31 ℃ for 108h,the α-amylase activity was highest.The optimum temperature and pH for this enzyme were 55 ℃ and 5.0,respectively.Ca2+stimulated α-amylase activity,while Fe2+、Fe3+、Mn2+、Ba2+和Cu2+inhibited its activity to some different extent.