Table 2.
Effects of different nitrogen sources supplemented to the potato starch on the production of α-amylase by P. stutzeri AS22.
| Nitrogen sources | Final pH value | Biomass (OD600) | α-Amylase activity (U/mL) |
|---|---|---|---|
| NH4Cl | 6.6 | 0.94 | 0.5 |
| (NH4)2SO4 | 6.5 | 0.9 | 0.7 |
| Soya peptone | 7.9 | 3.21 | 0.97 |
| Casein | 7.85 | 1.61 | 1.0 |
| Pastone | 7.78 | 3.08 | 1.5 |
| Yeast extract | 7.87 | 3.56 | 2.5 |
Cultivation was performed for 24 h at 37°C with shaking at 200 rpm in media that consisted of (g/L) potato starch 10, K2HPO4 1.4, KH2PO4 0.7, MgSO4 0.1, NaCl 0.5, and different nitrogen sources (1 g/L) and were adjusted to pH 8.0.