Study on the Production Rule and Enzymatic Property of Amylase Produced by Bacillus subtilis

[Objective]The research aimed to study the production rule and the enzymatic property of amylase produced by Bacillus subtilis which was separated from Jiande of Zhejiang.[Method]Bacillus subtilis which was separated was fermented,and the production rule of amylase was studied.The influences of temperature,pH and metal ions on the enzymatic property were studied.The double reciprocal curve was used to obtain Km of amylase.[Result]As the fermentation time prolonged,the amylase yield in the fermented liquid increased.When it was cultivated 30 h,the amylase yield reached the maximum value.The optimum reaction temperature and pH of amylase were respectively 40 ℃ and 7.5.The amylase had the certain thermal stability and was sensitive to the acid-base condition.Na +,K +,Ca2 +,Mg2 + had the activation effects,and Pb2 +,Hg2 + had the significant inhibition effects on the amylase.The influence of Cu2 + wasn't significant.Km of amylase was 2.31 × 10-3 mol/L.[Conclusion]The research had the strong guidance significance for the development and industrial application of amylase which was produced by the separated strain.