Table 5.
Regression coefficients and their significances for 3-Met production from the results of the Box–Behnken design.
| Source | Sum of Squares | DF | Mean Square | F Values | p Values | Significance |
|---|---|---|---|---|---|---|
| Model | 7.22573 | 9 | 0.80286 | 49.06 | 0.000 | *** |
| A—Fermentation time | 1.23168 | 1 | 1.23168 | 75.26 | 0.000 | *** |
| B—Yeast extract concentration | 1.27371 | 1 | 1.27371 | 77.83 | 0.000 | *** |
| C—Initial pH | 0.37036 | 1 | 0.37036 | 22.63 | 0.005 | ** |
| A2 | 0.22626 | 1 | 0.22626 | 13.83 | 0.014 | * |
| B2 | 2.41522 | 1 | 2.41522 | 147.58 | 0.000 | *** |
| C2 | 2.21996 | 1 | 2.21996 | 135.65 | 0.000 | *** |
| AB | 0.00101 | 1 | 0.00101 | 0.06 | 0.814 | - |
| AC | 0.10892 | 1 | 0.10892 | 6.66 | 0.049 | * |
| BC | 1.92710 | 1 | 1.92710 | 117.75 | 0.000 | *** |
| Residual | 0.08183 | 5 | 0.01637 | |||
| Lack of Fit | 0.04553 | 3 | 0.01518 | 0.84 | 0.585 | - |
| Pure Error | 0.03630 | 2 | 0.01815 | |||
| Cor Total | 7.30756 | 14 | ||||
| R2 = 0.9891 | R2Adj = 0.9694 |
Note: “-”, not significant (p > 0.05); “*”, significant at the 5% level (p < 0.05); “**”, significant at the 1% level (p < 0.01); “***”, significant at the 0.1% level (p < 0.001).