Table 1.
The analysis of Plackett-Burman design in twelve parallel assays.
| Source | Factor | −1 | +1 | Probability of T-test absolute value | Order |
|---|---|---|---|---|---|
| X4 | Fermentation time / day | 2 | 2.5 | 0.066279 | 5 |
| X5 | Content of carbon source / % | 1 | 1.25 | 0.096601 | 8 |
| X3 | Inoculation volume / mL | 1 | 1.25 | 0.062750 | 3 |
| X6 | Ratio of material to solution | 5 | 6.25 | 0.093976 | 7 |
| X7 | Fermentation Temperature / °C | 25 | 31.25 | 0.064036 | 4 |
| X1 | Range of pH value | 6.4 | 8.0 | 0.043727 | 1 |
| X2 | Content of nitrogen source / % | 0.61 | 0.76 | 0.048903 | 2 |
| X8 | Rotation per minute of flask | 144 |