Table 2.
Effects of different antioxidant compounds on LOX/RNO and LOX–FL reactions.
| Compound | Ki a or IC50 b | Antioxidant/Trolox c |
|---|---|---|
| LOX/RNO Reaction | ||
| Trolox | 7.0 ± 1.1 mM a,d | 1.00 |
| Resveratrol | 1.7 ± 0.2 mM a,d | 4.57 ± 0.33 e |
| Ferulic acid | 10.7 ± 2.1 mM a,d | 0.99 ± 0.11e |
| Gallic acid | 6.7 ± 1.3 mM a,d | 0.61 ± 0.05 e |
| Apigenin | 3.4 ± 0.5 mM a,d | 1.49 ± 0.09 e |
| Catechin | 13.6 ± 1.8 mM a,d | 0.42 ± 0.03 e |
| l-Ascorbic acid | 14.0 ± 1.9 mM a,d | 0.83 ± 0.09 e |
| Glutathione | 19.7 ± 3.2 mM b,d | n.d. |
| α-tocopherol | 1.1 ± 0.1 mM a,d | 3.43 ± 0.25 e |
| β-carotene | 7.8 ± 0.9 μM b,d | n.d. |
| LOX–FL Reaction | ||
| Trolox | 5 ± 0.6 μM a; 26 ± 2 μM b,d | 1.00 |
| Albumin | 25 ± 2 μM b,d | 1.04 ± 0.08 e,f |
| Bilirubin | 7.6 ± 0.6 μM b,d | 3.43 ± 0.28 e,f |
| l-Ascorbic acid | 1360 ± 10 μM b,d | 0.02 ± 0.002 e,f |
| Uric acid | 40 ± 2 μM b,d | 0.66 ± 0.04 e,f |
a Ki values were obtained by measuring reaction rates at different RNO or FL and antioxidant concentrations; b IC50 values represent the antioxidant concentration able to make half the rates of LOX/RNO (or LOX-mediated oxodiene generation in the case of glutathione) or LOX–FL reactions; c ratio between the gradient of the plot reporting the decrease of the rate (%) of LOX/RNO or LOX–FL reaction as a function of the antioxidant concentration and the gradient of the same plot relative to Trolox; d mean value ± standard deviation (n = 4); e mean value ± standard error (n = 4); f unpublished data; n.d. = not determined. Adapted from Pastore et al. [25] and Soccio et al. [26].