Table 2.
PSB isolation sources, phytase production characteristics and properties of phytases from selected PSB Isolates
| S. no. | Characteristic features | PSB isolates | |
|---|---|---|---|
| PSB-15 | PSB-45 | ||
| Culture characteristics | |||
| 1 | Sources of PSB isolate | Soybean rhizospheric soil | Compost |
| 2 | Maximum enzyme production time (h) | 48 | 48 |
| 3 | Maximum enzyme activity (U/ml) in PSM | 0.285 | 0.305 |
| 4 | Change in pH of production media after 72 h (Control-6.7) | 3.3 | 3.4 |
| 5 | Phosphorus solubilization index | 35 | 7 |
| Enzyme characteristics | |||
| 5 | Optimum pH | 6.0 | 7.0 |
| 6 | Optimum temperature | 50 °C | 70 °C |
| 7 | pH stability | 3-7 | 3-8 |
| 8 | Stability after 30 d at 4 °C/RT (% residual activity as compared to fresh enzyme) | 96.5/5.6 | 45.5/35.8 |
| 9 | K m (mM) | 1.25 | 0.48 |
| 10 | V max (μM/min) | 0.157 | 0.140 |