| Responses | Extraction conditions | Estimated responses | Morphology | ||||
|---|---|---|---|---|---|---|---|
| Ethanol conc. (%) | Extraction time (hr) | ||||||
| Max. | Min. | Max. | Min. | Max. | Min. | ||
| Brown color intensity (OD at 420 nm) | 78.1 | 2.37 | 2.38 | 2.32 | 0.75 | 0.37 | Maximum |
| Total phenolic compounds (μg/100 g) | 30.17 | 79.12 | 4.94 | 3.42 | 2,355 | 1,231 | Saddle point |
| ABTS radical scavenging activity (%) | 16.21 | 76.62 | 4.61 | 3.81 | 13.83 | 5.31 | Saddle point |
| Fe2+ chelating activity (%) | 0.76 | 79.55 | 3.39 | 3.30 | 58.54 | 25.41 | Saddle point |