Table 3 Plackett-burman design matrix of independent variables and their corresponding predicted and actual values of total carotenoid production under shaken flask cultivation at 37 °C, 200 rpm. The coded factors were X1 = sucrose, X2 = yeast extract, X3 = MgSO4·7H2O, X4 = pH, X5 = incubation time, X6 = inoculum volume, X7 = KCl, X8 = CaCl2·6H2O, and X9 = NaCl
Run | Coded factor |  | Total carotenoid (mg L− 1) | ||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
XA | XB | XC | XD | XE | XF | XG | XH | XI | Â | Predicted | Actual | Â | |||
1 | + 1 | -1 | + 1 | -1 | -1 | -1 | + 1 | + 1 | + 1 |  | 0.139 | 0.147 |  | ||
2 | + 1 | + 1 | -1 | + 1 | -1 | -1 | -1 | + 1 | + 1 |  | 0.357 | 0.350 |  | ||
3 | -1 | + 1 | + 1 | -1 | + 1 | -1 | -1 | -1 | + 1 |  | 0.023 | 0.023 |  | ||
4 | + 1 | -1 | + 1 | + 1 | -1 | + 1 | -1 | -1 | -1 |  | 0.620 | 0.620 |  | ||
5 | + 1 | + 1 | -1 | + 1 | + 1 | -1 | + 1 | -1 | -1 |  | 0.233 | 0.237 |  | ||
6 | + 1 | + 1 | + 1 | -1 | + 1 | + 1 | -1 | + 1 | -1 |  | 0.086 | 0.086 |  | ||
7 | -1 | + 1 | + 1 | + 1 | -1 | + 1 | + 1 | -1 | + 1 |  | 0.504 | 0.504 |  | ||
8 | -1 | -1 | + 1 | + 1 | + 1 | -1 | + 1 | + 1 | -1 |  | 0.571 | 0.564 |  | ||
9 | -1 | -1 | -1 | + 1 | + 1 | + 1 | -1 | + 1 | + 1 |  | 0.951 | 0.955 |  | ||
10 | + 1 | -1 | -1 | -1 | + 1 | + 1 | + 1 | -1 | + 1 |  | 0.395 | 0.387 |  | ||
11 | -1 | + 1 | -1 | -1 | -1 | + 1 | + 1 | + 1 | -1 |  | 0.045 | 0.045 |  | ||
12 | -1 | -1 | -1 | -1 | -1 | -1 | -1 | -1 | -1 | Â | 0.102 | 0.102 | Â | ||
13 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | Â | 0.921 | 0.955 | Â | ||
14 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | Â | 0.921 | 0.936 | Â | ||
15 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | Â | 0.921 | 0.929 | Â | ||