Molecular Identification of a Newly Isolated Bacillus subtilis BI19 and Optimization of Production Conditions for Enhanced Production of Extracellular Amylase
Table 1
Effect of different culture conditions for production of amylase by Bacillus subtilis BI19 in shake-flask fermentation.
Culture conditions
Amylase activity (U/mL/min)
Relative activity (%)
Incubation temperature (°C)
30
4.12 ± 0.31
56.82
32
5.59 ± 0.19
77.10
35
6.78 ± 0.94
93.51
37
7.25 ± 0.13
100.00
40
6.83 ± 0.45
94.20
42
5.20 ± 0.53
71.72
45
4.91 ± 0.45
67.72
Initial pH
6.0
4.75 ± 0.47
52.90
6.5
5.37 ± 0.81
69.11
7.0
7.19 ± 0.19
92.53
7.5
7.51 ± 0.26
96.65
8.0
7.77 ± 0.10
100.00
8.5
6.60 ± 0.43
84.94
9.0
4.99 ± 0.53
64.22
Incubation period (h)
12
3.61 ± 0.09
41.63
24
8.67 ± 0.08
100.00
36
7.44 ± 0.21
85.81
48
7.38 ± 0.14
85.12
60
7.29 ± 0.18
84.08
72
7.17 ± 0.07
82.70
Agitation speed (rpm)
100
2.43 ± 0.23
33.20
120
3.94 ± 0.07
53.82
140
6.87 ± 0.22
93.85
150
7.32 ± 0.15
100.00
160
7.04 ± 0.17
96.17
170
6.73 ± 0.09
91.93
180
5.81 ± 0.23
79.37
Fermentation medium (mL)
25
4.62 ± 0.52
63.55
50
7.27 ± 0.01
100.00
75
6.54 ± 0.19
89.96
100
6.04 ± 0.18
83.08
125
5.88 ± 0.07
80.88
150
5.09 ± 0.43
70.01
175
4.14 ± 0.31
56.95
Inoculum size (v/v %)
1
5.98 ± 0.11
82.48
2
7.25 ± 0.61
100.00
3
7.00 ± 0.12
96.55
4
6.66 ± 0.19
91.86
5
4.27 ± 0.18
58.90
Data represent as mean for three replicates ± standard deviation.
