Table 4 ANOVA and regression coefficients of the second-order polynomial model for the response variables
Factors | Yield | Surface tension | Inhibition diameter | ||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
DF | Coefficients | Sum of squares | F-value | p-value | DF | Coefficients | Sum of squares | F-value | p-value | DF | Coefficients | Sum of squares | F-value | p-value | |
X0, constant | 2.546 | 37.402 | 60.776 | ||||||||||||
Linear | |||||||||||||||
X1: Peptone | 1 | 0.246 | 0.771 | 29.63 | 0.0028** | 1 | − 3.023 | 115.658 | 85.14 | 0.0003*** | 1 | 5.979 | 437.292 | 16.78 | 0.0094** |
X2: Temperature | 1 | 0.157 | 0.311 | 11.98 | 0.0180* | 1 | − 1.072 | 14.542 | 10.70 | 0.0222* | 1 | 3.051 | 117.763 | 4.52 | 0.0868 |
X3: Molasses | 1 | 0.218 | 0.603 | 23.21 | 0.0048** | 1 | − 2.843 | 101.647 | 74.82 | 0.0003*** | 1 | 3.778 | 180.6 | 6.93 | 0.0464* |
Quadratic | |||||||||||||||
X 21 | 1 | − 0.458 | 2.267 | 87.14 | 0.0002*** | 1 | 3.790 | 155.245 | 114.28 | 0.0001*** | 1 | − 7.283 | 573.377 | 22.01 | 0.0054** |
X 22 | 1 | − 0.864 | 8.079 | 310.44 | 0.0000*** | 1 | 7.287 | 573.95 | 422.49 | 0.0000*** | 1 | − 21.376 | 4938.56 | 189.55 | 0.000*** |
X 23 | 1 | − 0.322 | 1.124 | 43.21 | 0.0012** | 1 | 3.194 | 110.272 | 81.17 | 0.0003*** | 1 | − 10.777 | 1255.19 | 48.18 | 0.0010** |
Interaction | |||||||||||||||
X 1 X 2 | 1 | 0.094 | 0.072 | 2.77 | 0.1571 | 1 | − 0.735 | 4.321 | 3.18 | 0.1346 | 1 | − 0.161 | 0.208012 | 0.01 | 0.9323 |
X 1 X 3 | 1 | − 0.395 | 1.248 | 47.99 | 0.0010** | 1 | 5.192 | 215.696 | 158.78 | 0.0001*** | 1 | − 9.368 | 702.188 | 26.95 | 0.0035** |
X 2 X 3 | 1 | − 0.070 | 0.039 | 1.51 | 0.2736 | 1 | 0.367 | 1.080 | 0.80 | 0.4133 | 1 | − 0.243 | 0.475313 | 0.02 | 0.8978 |
Lack of fit | 5 | 0.401 | 3.08 | 0.1209 | 5 | 27.329 | 4.02 | 0.0764 | 5 | 109.353 | 0.84 | 0.5738 | |||
Pure error | 5 | 0.130 | 5 | 6.792 | 5 | 130.269 | |||||||||
Total (corr.) | 19 | 15.050 | 19 | 1326.53 | 19 | 8445.28 | |||||||||
R2 (%) | 96.46 | 97.15 | 97.42 | ||||||||||||
Adjusted R2 (%) | 93.29 | 94.59 | 95.11 | ||||||||||||
AAD | 0.012 | 0.03 | 0.026 | ||||||||||||
A f | 1.11 | 1.08 | 1.08 | ||||||||||||
B f | 1.04 | 0.99 | 0.99 | ||||||||||||