Table 1 Plackett-Burman (PB) experimental design for the initial screening of fermentation variables. IPTG Isopropyl β-d-thiogalactoside
Experiment number | Tryptone (g/L) (X1) | Yeast extract (g/L) (X2) | Glucose (g/L) (X3) | NaCl (g/L) (X4) | Inoculum size (%) (X5) | Time (h) (X6) | Temperature (°C) (X7) | IPTG (mM/mL) (X8) | Induction time (h) (X9) | Lipase activity (IU/mL)a | Cell concentration (mg/mL)a |
|---|---|---|---|---|---|---|---|---|---|---|---|
1 | 25 | 1 | 90 | 1 | 1 | 8 | 25 | 2.5 | 5 | 26.9 ± 2.8 | 2.3 ± 0.5 |
2 | 25 | 9 | 10 | 9 | 1 | 8 | 25 | 0.5 | 5 | 0.6 ± 1.9 | 1.2 ± 0.7 |
3 | 5 | 9 | 90 | 1 | 9 | 8 | 25 | 0.5 | 1 | 33.2 ± 2.6 | 3.5 ± 0.5 |
4 | 25 | 1 | 90 | 9 | 1 | 25 | 25 | 0.5 | 1 | 24.0 ± 3.6 | 2.4 ± 0.7 |
5 | 25 | 9 | 10 | 9 | 9 | 8 | 49 | 0.5 | 1 | 1.0 ± 2.5 | 1.3 ± 0.3 |
6 | 25 | 9 | 90 | 1 | 9 | 25 | 25 | 2.5 | 1 | 31.9 ± 4.1 | 3.1 ± 0.6 |
7 | 5 | 9 | 90 | 9 | 1 | 25 | 49 | 0.5 | 5 | 0.2 ± 2.6 | 1.0 ± 0.7 |
8 | 5 | 1 | 90 | 9 | 9 | 8 | 49 | 2.5 | 1 | 11.0 ± 2.5 | 2.2 ± 0.6 |
9 | 5 | 1 | 10 | 9 | 9 | 25 | 25 | 2.5 | 5 | 4.4 ± 1.4 | 2.1 ± 0.6 |
10 | 25 | 1 | 10 | 1 | 9 | 25 | 49 | 0.5 | 5 | 0.9 ± 3.7 | 1.8 ± 0.3 |
11 | 5 | 9 | 10 | 1 | 1 | 25 | 49 | 2.5 | 1 | 6.4 ± 1.4 | 1.5 ± 0.8 |
12 | 5 | 1 | 10 | 1 | 1 | 8 | 49 | 2.5 | 5 | 0.8 ± 3.2 | 1.4 ± 0.4 |
Estimates | 0.0277 | -0.2619 | 0.14665 | -1.2322 | 0.1276 | -0.0562 | -0.5287 | -0.11205 | -2.1805 | -- | -- |
t values | 0.3574 | -1.3349 | 7.5688 | -6.9091 | 0.7155 | -0.7269 | -8.2645 | -0.1349 | -5.2484 | -- | -- |
P values | 0.7550 | 0.3135 | 0.0170* | 0.0203* | 0.5486 | 0.5428 | 0.0143* | 0.0905 | 0.0344* | -- | -- |