Table 4.
Concentration of milk thistle-based dietary supplement that gives half-maximal response (EC50, mg/L) for different antioxidant activity assays. The lower is the EC50 value, the higher is the anti-radical activity. The EC50 values were obtained using the GraphPad Prism 7 software, and are presented as an average of three replicates with standard errors of the mean (SEM). The statistical significance was assessed by one-way analysis of variance (ANOVA) followed by Duncan’s post-hoc test (p > 0.05), and is indicated by superscripts. Statistically significant levels were denoted with different letters.
| Sample No. | EC50 [mg/L] | |||
|---|---|---|---|---|
| ABTS | ORAC | DPPH | CAA | |
| 1 | 8.5 ± 0.5 a | 43.3 ± 3.2 f,g | 120.8 ± 6.9 c,d | >25.0 |
| 2 | 17.4 ± 2.2 b | 30.7 ± 3.0 e | 73.0 ± 2.8 b | >25.0 |
| 3 | 8.7 ± 0.9 a | 90.8 ± 6.4 i | 9.7 ± 2.3 a | 11.3 ± 0.2 a |
| 4 | >66.7 | >200.0 | >166.7 | >25.0 |
| 5 | >66.7 | >200.0 | >166.7 | >25.0 |
| 6 | >66.7 | 122.8 ± 14.7 j | >166.7 | >25.0 |
| 7 | 38.7 ± 2.3 h | 56.9 ± 1.3 h | >166.7 | >25.0 |
| 8 | 18.7 ± 2.0 b | 53.8 ± 0.7 g,h | 108.3 ± 7.0 c | 21.2 ± 3.6 b,c,d,e,f |
| 9 | 20.4 ± 1.2 b,d | 30.5 ± 3.3 e | 58.7 ± 15.2 b | 24.3 ± 4.0 d,e,f |
| 10 | >66.7 | >200.0 | >166.7 | >25.0 |
| 11 | 25.7 ± 1.8 d,e,f | 31.0 ± 3.3 e | >166.7 | 21.8 ± 2.9 c,d,e,f |
| 12 | 27.6 ± 3.0 e,f,g | 26.9 ± 0.7 c,d,e | 130.4 ± 9.2 c,d | 27.3 ± 2.6 f |
| 13 | 32.3 ± 2.8 g | 33.8 ± 5.1 e,f | > 166.7 | >25.0 |
| 14 | 27.9 ± 3.1 e,f,g | 28.8 ± 0.1 d,e | 128.3 ± 15.0 c,d | 13.5 ± 1.7 a,b,c |
| 15 | 48.4 ± 0.7 i | 53.5 ± 0.7 g,h | > 166.7 | 21.7 ± 3.5 c,d,e,f |
| 16 | >66.7 | >200.0 | >166.7 | >25.0 |
| 17 | 12.0 ± 0.3 a,c | 13.9 ± 0.5 a,b | 51.0 ± 1.4 b | 12.5 ± 0.7 a |
| 18 | 9.9 ± 0.3 a | 16.7 ± 2.4 a,b,c,d | 106.9 ± 3.0 c | 16.9 ± 2.3 a,b,c,d |
| 19 | 10.3 ± 0.7 a | 16.2 ± 2.0 a,b,c | 131.4 ± 10.5 c,d | 17.9 ± 0.7 a,b,c,d,e |
| 20 | 20.9 ± 2.8 b,d | 12.6 ± 1.2 a | 143.4 ± 3.0 d | 16.7 ± 0.8 a,b,c,d |
| 21 | 17.5 ± 1.9 b,c | 24.8 ± 0.6 b,c,d,e | 128.4 ± 2.9 c,d | 18.5 ± 3.0 a,b,c,d,e |
| 22 | 18.0 ± 1.8 b | 27.4 ± 1.0 c,d,e | 125.4 ± 9.8 c,d | 26.4 ± 2.1 e,f |
| 23 | 20.7 ± 1.1 b,d | 28.7 ± 0.1 d,e | 145.9 ± 9.0 d | 18.4 ± 0.8 a,b,c,d,e |
| 24 | 23.5 ± 1.8 b,d,e | 59.6 ± 4.5 h | 206.5 ± 1.1 f | 22.8 ± 3.6 d,e,f |
| 25 | 31.2 ± 2.4 f,g | 44.2 ± 3.6 f,g | 116.0 ± 7.8 c,d | >25.0 |
| 26 | 17.7 ± 1.5 b,c | 25.8 ± 0.6 c,d,e | 181.5 ± 2.7 e | 12.9 ± 1.4 a,b |
| Silymarin SA | 12.8 ± 2.6 | 11.0 ± 0.1 | >166.7 | 18.5 ± 3.7 |
| Silymarin mimicking mixture of flavonoid/flavonolignans | 1.7 ± 0.3 | 23.4 ± 2.7 | >166.7 | >25.0 |
| Quercetin | >1.7 | 5.6 ± 0.1 | 4.5 ± 0.1 | 1.0 ± 0.0 |
| Trolox | >6.7 | >200.0 | 5.1 ± 0.1 | 0.7 ± 0.1 |
| Silibinin SA | 9.1 ± 0.9 | 19.2 ± 2.2 | >166.7 | >25.0 |