Table 2.
Half maximal effective concentration (EC50), Trolox equivalents antioxidant capacity (TEAC) and ferric reducing antioxidant power (FRAP) values of Sorbus torminalis extracts and standards.
| Extract | EC50 ABTS (mg/mL) | TEAC (ABTS) (mM) | EC50 DPPH (mg/mL) | TEAC (DPPH) (mM) | EC50 O2−(mg/mL) | FRAP (mM) |
|---|---|---|---|---|---|---|
| Water | 5.30 ± 0.166a | 1.37 ± 0.051a | 5.69 ± 0.364a | 0.85 ± 0.019a | 9.01 ± 1.025a | 3.51 ± 0.060a |
| Ethyl acetate | 9.30 ± 0.449b | 0.94 ± 0.0470b | 6.08 ± 1.263a | 0.73 ± 0.033b | 7.41 ± 0.887a | 1.60 ± 0.060b |
| Acetone | 13.23 ± 0.341c | 0.71 ± 0.091c | 10.21 ± 0.230b | 0.59 ± 0.015c | 18.64 ± 1.162b | 1.17 ± 0.027c |
| Methanol | 27.53 ± 4.097d | 0.50 ± 0.084d | 32.31 ± 2.615c | 0.19 ± 0.052d | 48.47 ± 4.779c | 0.45 ± 0.020d |
| Quercetin | 0.12 ± 0.001e | 1.42 ± 0.028e | 0.07 ± 0.001d | 0.97 ± 0.002e | 0.53 ± 0.037d | 3.24 ± 0.136e |
| α-tocopherol | 0.49 ± 0.035f | 1.64 ± 0.004f | 0.24 ± 0.018e | 0.97 ± 0.009f | — | 4.10 ± 0.240f |
Data are presented as the mean of three replicates ± standard deviation. Different superscript letters in the same column indicate a significant difference (p < 0.05). EC50 is the effective concentration for which the antioxidant activity was 50% and was obtained by interpolation from linear regression analysis. TEAC and FRAP values; for extracts at 10 mg/mL and for quercetin at 0.25 mg/mL concentration. For α-tocopherol TEAC (ABTS) and FRAP values at 1.25 mg/mL; and TEAC (DPPH) value at 0.5 mg/mL concentration.
ABTS = 2,2′-azino-bis(3-ethylbenzothioazoline-6-sulphonic acid); DPPH = 2,2′-diphenyl-1-picrylhydrazyl.