Table 1.
Central composite circumscribed (CCC) design with five levels and three variables for phenolic compound extraction in D. indicum var. aromaticum flower and observed responsesa.
| Run order | Independent variables | TP content (g GAEb/100 g DW) | |||||
|---|---|---|---|---|---|---|---|
| Coded | Uncoded | ||||||
| Time (min) | Solid/liquid ratio (g/mL) | Temperature (°C) | Time (min) | Solid/liquid ratio (g/mL) | Temperature (°C) | ||
| 1 | −1 | −1 | −1 | 20 | 1:10 | 40 | 0.71 |
| 2 | 1 | −1 | −1 | 40 | 1:10 | 40 | 0.93 |
| 3 | −1 | 1 | −1 | 20 | 1:30 | 40 | 1.16 |
| 4 | 1 | 1 | −1 | 40 | 1:30 | 40 | 1.04 |
| 5 | −1 | −1 | 1 | 20 | 1:10 | 60 | 0.84 |
| 6 | 1 | −1 | 1 | 40 | 1:10 | 60 | 1.03 |
| 7 | −1 | 1 | 1 | 20 | 1:30 | 60 | 1.27 |
| 8 | 1 | 1 | 1 | 40 | 1:30 | 60 | 1.21 |
| 9 | −1.68 | 0 | 0 | 13 | 1:20 | 50 | 1.11 |
| 10 | 1.68 | 0 | 0 | 47 | 1:20 | 50 | 1.28 |
| 11 | 0 | −1.68 | 0 | 30 | 1:03 | 50 | 0.68 |
| 12 | 0 | 1.68 | 0 | 30 | 1:37 | 50 | 1.23 |
| 13 | 0 | 0 | −1.68 | 30 | 1:20 | 33 | 0.89 |
| 14 | 0 | 0 | 1.68 | 30 | 1:20 | 67 | 1.13 |
| 15 | 0 | 0 | 0 | 30 | 1:20 | 50 | 1.02 |
| 16 | 0 | 0 | 0 | 30 | 1:20 | 50 | 1.20 |
| 17 | 0 | 0 | 0 | 30 | 1:20 | 50 | 1.07 |
| 18 | 0 | 0 | 0 | 30 | 1:20 | 50 | 1.26 |
| 19 | 0 | 0 | 0 | 30 | 1:20 | 50 | 1.15 |
| 20 | 0 | 0 | 0 | 30 | 1:20 | 50 | 1.07 |
aExperimental results for TP content are mean value of triplicates.
bGallic acid equivalent.