Table 2 Experimental design and results of the central composite design
Run | pH value | Mannose conc. (g/L) | Meat extract conc. (g/L) | Incubation time (day) | α-Galactosidase activity (U/mL) | ||
|---|---|---|---|---|---|---|---|
Actual | Predicted | Residual | |||||
1 | 5.5 | 15 | 7.5 | 5 | 22.528 | 20.166 | 2.352 |
2 | 4.5 | 12.5 | 5 | 6 | 17.339 | 17.749 | − 0.410 |
3 | 5.5 | 10 | 7.5 | 5 | 16.708 | 16.199 | 0.509 |
4 | 4.5 | 7.5 | 5 | 6 | 10.559 | 11.684 | − 1.124 |
5 | 5.5 | 10 | 7.5 | 7 | 22.959 | 21.118 | 1.842 |
6 | 4.5 | 7.5 | 10 | 4 | 11.692 | 12.034 | − 0.342 |
7 | 6.5 | 7.5 | 5 | 4 | 7.023 | 8.342 | − 1.319 |
8 | 5.5 | 5 | 7.5 | 5 | 9.046 | 10.686 | − 1.640 |
9 | 4.5 | 12.5 | 10 | 6 | 25.199 | 25.436 | − 0.237 |
10 | 5.5 | 10 | 12.5 | 5 | 19.059 | 17.469 | 1.591 |
11 | 6.5 | 12.5 | 10 | 4 | 12.557 | 12.988 | − 0.431 |
12 | 6.5 | 7.5 | 5 | 6 | 12.367 | 10.581 | 1.786 |
13 | 5.5 | 10 | 7.5 | 5 | 15.981 | 16.199 | − 0.218 |
14 | 5.5 | 10 | 7.5 | 3 | 8.925 | 10.055 | − 1.130 |
15 | 6.5 | 7.5 | 10 | 4 | 10.828 | 9.574 | 1.254 |
16 | 5.5 | 10 | 7.5 | 5 | 16.327 | 16.199 | 0.128 |
17 | 5.5 | 10 | 7.5 | 5 | 16.146 | 16.199 | − 0.053 |
18 | 6.5 | 7.5 | 10 | 6 | 15.765 | 16.815 | − 1.050 |
19 | 6.5 | 12.5 | 5 | 4 | 8.579 | 7.922 | 0.658 |
20 | 3.5 | 10 | 7.5 | 5 | 16.439 | 16.696 | − 0.257 |
21 | 6.5 | 12.5 | 10 | 6 | 23.219 | 25.552 | − 2.333 |
22 | 4.5 | 12.5 | 10 | 4 | 15.669 | 16.612 | − 0.942 |
23 | 4.5 | 7.5 | 10 | 6 | 15.722 | 15.536 | 0.186 |
24 | 4.5 | 12.5 | 5 | 4 | 13.422 | 13.928 | − 0.506 |
25 | 7.5 | 10 | 7.5 | 5 | 12.938 | 11.969 | 0.968 |
26 | 5.5 | 10 | 7.5 | 5 | 16.984 | 16.199 | 0.785 |
27 | 6.5 | 12.5 | 5 | 6 | 14.269 | 15.483 | − 1.214 |
28 | 5.5 | 10 | 2.5 | 5 | 7.672 | 8.551 | − 0.879 |
29 | 5.5 | 10 | 7.5 | 5 | 15.047 | 16.199 | − 1.151 |
30 | 4.5 | 7.5 | 5 | 4 | 16.362 | 13.185 | 3.177 |