Table 3.
In vitro antioxidant activity.
| Sample | DPPH Test IC50 (μg/mL) | ABTS Test IC50 (μg/mL) | β-Carotene Bleaching Test IC50 (μg/mL) | FRAP Test (μM Fe (II)/g) | |
|---|---|---|---|---|---|
| t 30 min | t 60 min | ||||
| Feed | 61.3 ± 3.5 **** | 15.2 ± 1.5 *** | 48.8% | 34.0% | 59.4 ± 1.7 ** |
| MF-P | 53.5 ± 3.3 **** | 7.7 ± 0.8 ** | 50.0 ± 2.9 **** | 40.1% | 66.6 ± 1.8 * |
| NF-R | 52.6 ± 3.2 **** | 7.3 ± 1.6 ** | 32.3 ± 1.9 **** | 69.0 ± 3.5 **** | 86.5 ± 1.9 |
| NF-P | 146.9 ± 4.2 **** | 112.8 ± 1.9 **** | 95.4 ± 4.0 **** | 31.2% | 10.7 ± 1.7 **** |
| RO-R | 38.0 ± 1.9 **** | 6.9 ± 1.9 * | 25.1 ± 1.2 **** | 54.7 ± 3.3 **** | 91.9 ± 1.6 |
| RO-P | 310.2 ± 4.7 **** | 17.5% | 23.51% | 19.2% | 3.6% |
| Positive control | |||||
| Ascorbic acid | 5.1 ± 0.9 | 1.7 ± 0.5 | |||
| Propyl gallate | 0.09 ± 0.02 | 0.09 ± 0.01 | |||
| BHT | 63.4 ± 2.5 | ||||
MF, microfiltration; NF, nanofiltration; RO, reverse osmosis; P, permeate; R, retentate. Data are expressed as means ± S.D. (n = 3). Differences within and between groups were evaluated by one-way ANOVA followed by a multicomparison Dunnett’s test (α = 0.05): **** p < 0.0001, *** p < 0.001, ** p < 0.01, * p < 0.1 compared with the positive control.