Table 2.
Comparison of total phenolics contents, flavonoids contents, and antioxidant activities of OJ among extraction solvents. Means in a row followed by same superscript letters are not significantly different according to Duncan’s test at p < 0.05.
| Extraction solvent, temperature, and time | |||||
|---|---|---|---|---|---|
| Subcritical water 220 °C and 15 min | Methanol 25 °C and 2 h | Ethanol 25 °C and 2 h | Methanol 60 °C and 2 h | Ethanol 60 °C and 2 h | |
| Total phenolics content (mg GAE/g) | 39.9 ± 4.1c | 6.87 ± 0.4ab | 3.5 ± 0.3a | 10.7 ± 1.3b | 8.0 ± 2.6b |
| Total flavonoids content (mg QE/g) | 11.4 ± 0.6c | 4.03 ± 0.2a | 3.6 ± 0.8a | 5.8 ± 1.2b | 6.1 ± 1.0b |
| DPPH-radical-scavenging ability (%) | 90.3 ± 2.2c | 89.57 ± 1.7bc | 70.9 ± 4.3a | 89.7 ± 0.3bc | 81.0 ± 9.2b |
| ABTS-radical-scavenging ability (%) | 96.0 ± 2.9d | 57.70 ± 3.0b | 19.6 ± 0.8a | 78.7 ± 9.9c | 57.0 ± 11.3b |
| FRAP antioxidant activity (mg TE/g) | 662.4 ± 17.2c | 328.9 ± 11.0b | 130.6 ± 18.0a | 318.7 ± 6.1b | 177.1 ± 7.4a |
The data are mean ± SD values (n = 3).