B. cereus was isolated from rotten potatoes. A loopful of culture
was transferred from the stock culture to a culture plate. The culture
plate was incubated at 37 C for 48 h. Then, the single colonies
formed was transferred to a 50 ml of medium containing 1% (w/v)
sago starch, 0.5% (w/v) peptone, 0.5% (w/v) yeast extract, 0.009%
(w/v) MgSO4, 0.1% K2HPO4 and 1% Na2CO3. The culture was allowed
to grow aerobically at 37 C with continuous agitation at
250 rpm for 18 h. This was then applied as inoculum. A 10 ml of
inoculum was then transferred into a 250 ml Erlenmeyer flask consisting
100 ml of the same medium mentioned previously and
incubated at 37 C at 250 rpm for 30 h with continuous shaking
[2]. The crude enzyme was harvested after 15 min of centrifugation
at 4000g as supernatant and was directly used for further studies