摘要：The current study aimed to examine the amylolytic activities of various species of
the Bacillus genus. A total of 31% of the tested 166 strains showed a positive
reaction on starch agar. Their amylolytic activity was in the range of 0.9 to 2.8 U/ml.
Bacillus cereus №10 showed the highest initial activity, established in the late
stationary phase of growth (36 hours of incubation). The effects of different nitrogen
sources, metal ions and different type of secondary carbon sources (starch was used
as a primary carbon source) on the production of amylase by the screened strain
were studied. The enzyme production was significantly influenced by the type and
concentration of the secondary carbon source. Replacement of peptone by yeast
extract and the addition of 1 mM Ca2+ increased initial amylolytic activity by 153%
reaching 4.29±0.63 U/ml.
关键词：Bacillus cereus; amylase; enzyme production; nutritive medium
optimization
