Table 4.
Effect of the Tested Compounds on the Fenton Reaction.
| Compound | Range of •OH Formation (%) a | ||
|---|---|---|---|
| Iron (II) | Iron (III) | Copper (I) | |
| 3-Hydroxyphenylacetic acid | 0–22 | 0–21 | 6–131 |
| 3,4-Dihydroxyphenylacetic acid (DOPAC) | 0–13 | 0–11 | 64–280 |
| 5-Chloro-7-iodo-8-hydroxyquinoline | 4–17 | 3–23 | 16–131 |
| Catechin | 2–12 | 2–11 | 23–127 |
| EDTA b | - | - | 3–113 |
| Homovanillic acid (HVA) | 1–51 | 0–100 | 0–174 |
| Quercetin | 3–21 | 3–21 | 14–136 |
| Phloroglucinol | 3–20 | 2–25 | 44–149 |
| Trientine b | - | - | 1–128 |
a Calculated as: (amount of •OH formed with the compound/amount of •OH formed without the compound) × 100; n = 3. Higher values correspond to lower antioxidant powers; values higher than 100% correspond to prooxidant activities. b EDTA and trientine were not tested as antioxidants with iron.