Table 2.
Experimental design and results of design of experiments.
| No. | A (min) | B (℃) | C (W) | D (mL/g) | E (%) | FRAP (μmol Fe2+/g DW) | DPPH (μmol Trolox/g DW) |
|---|---|---|---|---|---|---|---|
| 1 | 40 | 30 | 400 | 30 | 60 | 41.7 ± 0.26 | 39.7 ± 0.26 |
| 2 | 80 | 30 | 400 | 30 | 40 | 32.5 ± 0.34 | 27.9 ± 0.74 |
| 3 | 40 | 30 | 560 | 40 | 60 | 39.9 ± 0.95 | 45.2 ± 0.87 |
| 4 | 80 | 30 | 560 | 30 | 60 | 43.1 ± 1.00 | 40.4 ± 0.83 |
| 5 | 80 | 50 | 560 | 30 | 40 | 40.0 ± 0.52 | 36.7 ± 0.90 |
| 6 | 40 | 50 | 560 | 40 | 40 | 35.4 ± 0.78 | 32.6 ± 0.40 |
| 7 | 40 | 50 | 400 | 30 | 40 | 34.0 ± 0.41 | 31.0 ± 0.79 |
| 8 | 80 | 30 | 560 | 40 | 40 | 42.9 ± 1.00 | 39.0 ± 0.36 |
| 9 | 40 | 30 | 400 | 40 | 40 | 41.3 ± 0.36 | 37.4 ± 0.20 |
| 10 | 40 | 50 | 400 | 40 | 60 | 42.7 ± 0.85 | 37.0 ± 1.03 |
| 11 | 80 | 50 | 400 | 30 | 60 | 49.3 ± 1.18 | 40.0 ± 0.69 |
| 12 | 40 | 30 | 560 | 30 | 40 | 27.6 ± 0.26 | 21.5 ± 0.15 |
| 13 | 80 | 30 | 400 | 40 | 60 | 45.8 ± 0.94 | 45.3 ± 0.92 |
| 14 | 80 | 50 | 400 | 40 | 40 | 44.8 ± 0.79 | 39.5 ± 0.81 |
| 15 | 40 | 50 | 560 | 30 | 60 | 43.2 ± 0.86 | 39.0 ± 0.38 |
| 16 | 80 | 50 | 560 | 40 | 60 | 49.7 ± 0.95 | 43.3 ± 0.76 |
A, extraction time; B, extraction temperature; C, ultrasonic power; D, liquid to solid ratio; E, acetone concentration. FRAP: ferric ion reducing antioxidant power; DW: dry weight; DPPH: 2, 2−diphenyl−1−picrylhydrazyl free radical scavenging activity.