Table 2.
Central composite design by RSM program for optimization of extraction conditions with experimental and their corresponding predicted yields.
| Runs | Extraction temperature (X 1, °C) |
Extraction time (X 2, hours) |
Extraction cycles (X 3, cycle) |
Experimental yield (%) | Predicted yield (%) |
|---|---|---|---|---|---|
| 1 | 40 (0) | 32 (0) | 12 (0) | 13.29 | 11.51 |
| 2 | 50 (1) | 16 (−1) | 20 (1) | 8.16 | 8.86 |
| 3 | 40 (0) | 32 (0) | 12 (0) | 10.26 | 11.51 |
| 4 | 30 (−1) | 48 (1) | 20 (1) | 11.32 | 11.09 |
| 5 | 23.18 (−1.68) | 32 (0) | 12 (0) | 12.89 | 13.09 |
| 6 | 56.82 (1.68) | 32 (0) | 12 (0) | 9.67 | 9.94 |
| 7 | 40 (0) | 5.09 (−1.68) | 12 (0) | 11.93 | 11.51 |
| 8 | 40 (0) | 32 (0) | −1.45 (−1.68) | 11.36 | 11.91 |
| 9 | 50 (1) | 48 (1) | 4 (−1) | 12.19 | 11.82 |
| 10 | 40 (0) | 32 (0) | 25.45 (1.68) | 10.83 | 11.12 |
| 11 | 30 (−1) | 48 (1) | 4 (−1) | 11.97 | 11.20 |
| 12 | 40 (0) | 32 (0) | 12 (0) | 11.31 | 11.51 |
| 13 | 30 (−1) | 16 (−1) | 04 (−1) | 13.67 | 14.29 |
| 14 | 50 (1) | 16 (−1) | 04 (−1) | 9.53 | 9.68 |
| 15 | 40 (0) | 58.91 (1.68) | 12 (0) | 9.67 | 11.52 |
| 16 | 40 (0) | 32 (0) | 12 (0) | 12.73 | 11.51 |
| 17 | 50 (1) | 48 (1) | 20 (1) | 12.65 | 11.96 |
| 18 | 40 (0) | 32 (0) | 12 (0) | 12.42 | 11.51 |
| 19 | 30 (−1) | 16 (−1) | 20 (1) | 12.92 | 13.21 |