%0 Journal Article
%T Production of ¦Á-Amylase by Bacillus subtilis QM3 and its Enzymatic Properties
%A Qingping Hu
%A Jingjing Liu
%J Open Access Library Journal
%V 8
%N 3
%P 1-8
%@ 2333-9721
%D 2021
%I Open Access Library
%R 10.4236/oalib.1107291
%X Alpha-amylase is a starch hydrolyzing enzyme which has many industrial applications. In this study, Bacillus subtilis QM3 has ability to produce ¦Á-amylase. Identification was done by iodine test, based on the clear zone around the sample in starch agar plates. Alpha-amylase activity was measured using 3,5-dinitrosalicylic acid (DNS). The result showed B. subtilis QM3 can produce ¦Á-amylase and activity of ¦Á-amylase was 50.58 IU/mL. The study on enzymatic properties was found: the optimum temperature is 70&deg;C, and its stability is high at 30&deg;C - 70&deg;C. The optimum pH is 6.0, and the stability is high under the condition of pH was 6.0 - 7.0. Ca<sup>2 </sup>, Na<sup> </sup>, K<sup> </sup> and Mg<sup>2 </sup> promoted the activity of alpha-amylase, and their relative enzyme activities were 130.1%, 118.1%, 115.9% and 110.4% respectively. Fe<sup>2 </sup>, Zn<sup>2 </sup>, Cu<sup>2 </sup>, Mn<sup>2 </sup> and EDTA inhibited the activity of alpha-amylase. The relative enzyme activities were 86.1% 77.8%, 67.4%, 64.2% and 48.4% respectively.
%K Bacillus subtilis QM3
%K Alpha-Amylase
%K Enzymological Properties
%U http://www.oalib.com/paper/6527235