Table 3.
Box–Benhken experimental design in terms of actual and coded factors applied to the aqueous extraction conditions and experimental values of the response variables. Antioxidant capacity indicators are expressed per gram of EOP.
| Run | T (°C) |
t (min) |
B (%w/v) |
Yield (%) |
Phenolic Concentration (g GAE/L) |
TPC (mg GAE) |
TFC (mg RE) |
DPPH (mg TE) |
ABTS (mg TE) |
FRAP (mg TE) |
|---|---|---|---|---|---|---|---|---|---|---|
| 1 | 25 (−1) | 60 (0) | 25 (1) | 28.7 | 6.7 | 28.8 | 82.7 | 25.8 | 98.6 | 28.7 |
| 2 | 55 (0) | 60 (0) | 15 (0) | 30.6 | 4.6 | 32.9 | 100.1 | 34.5 | 105.9 | 34.8 |
| 3 | 55 (0) | 30 (−1) | 25 (1) | 28.7 | 6.0 | 25.8 | 78.5 | 26.3 | 93.4 | 29.8 |
| 4 | 85 (1) | 90 (1) | 15 (0) | 34.5 | 5.2 | 37.0 | 106.6 | 42.1 | 142.9 | 43.7 |
| 5 | 55 (0) | 60 (0) | 15 (0) | 32.1 | 4.8 | 34.3 | 97.7 | 35.7 | 114.3 | 38.1 |
| 6 | 85 (1) | 60 (0) | 25 (1) | 33.6 | 7.4 | 31.7 | 94.6 | 26.6 | 118.2 | 39.4 |
| 7 | 85 (1) | 30 (−1) | 15 (0) | 32.0 | 4.7 | 33.4 | 104.5 | 39.7 | 124.6 | 40.9 |
| 8 | 55 (0) | 60 (0) | 15 (0) | 32.9 | 4.9 | 35.2 | 113.4 | 39.7 | 118.2 | 40.7 |
| 9 | 25 (−1) | 60 (0) | 5 (−1) | 27.7 | 1.4 | 38.0 | 148.7 | 44.1 | 115.9 | 37.6 |
| 10 | 55 (0) | 90 (1) | 25 (1) | 31.9 | 7.1 | 30.6 | 86.5 | 26.4 | 105.1 | 29.1 |
| 11 | 25 (−1) | 30 (−1) | 15 (0) | 26.9 | 3.6 | 25.8 | 90.7 | 31.4 | 93.5 | 25.1 |
| 12 | 55 (0) | 90 (1) | 5 (−1) | 35.6 | 2.0 | 43.6 | 155.6 | 46.4 | 130.1 | 41.6 |
| 13 | 55 (0) | 30 (−1) | 5 (−1) | 30.6 | 1.9 | 41.2 | 153.4 | 46.5 | 125.4 | 43.7 |
| 14 | 55 (0) | 60 (0) | 15 (0) | 32.1 | 4.9 | 34.9 | 104.2 | 36.9 | 119.7 | 35.1 |
| 15 | 85 (1) | 60 (0) | 5 (−1) | 33.2 | 1.9 | 41.2 | 157.6 | 49.2 | 140.5 | 42.3 |
| 16 | 25 (−1) | 90 (1) | 15 (0) | 29.9 | 4.2 | 29.7 | 95.6 | 33.6 | 108.3 | 30.9 |
| 17 | 55 (0) | 60 (0) | 15 (0) | 33.0 | 4.9 | 35.0 | 102.7 | 37.8 | 132.9 | 36.5 |
T: temperature (°C); t: time (min); B: biomass loading (%w/v).