Table 1.
A List of Major Reactive Oxygen Species and Antioxidant Systems in Living Organisms
|
ROS |
Symbol |
Antioxidant system |
Symbol |
|---|---|---|---|
| Radical ROS | Enzymatic | ||
| Superoxide | O2•− | Superoxide dismutase | SOD |
| Hydroxyl radical | •OH | Catalase | CAT |
| Nitric oxidea | NO• | Glutathione peroxidase | GPx |
| Organic radical | R• | Glutathione reductase | GR |
| Peroxyl radical | ROO• | Glutathione-S-transferase | GST |
| Alkoxyl radical | RO• | Thioredoxin peroxidase | TrxPx |
| Thiyl radical | RS• | Thioredoxin reductase | TrxR |
| Sulphonyl radical | ROS• | ||
| Thiyl peroxyl radical | RSOO• |
| Nonradical ROS/RNS | Nonenzymatic | ||
|---|---|---|---|
| Hydrogen peroxide | H2O2 | Glutathione | GSH |
| Singlet oxygen | 1O2 | Glutaredoxin | Grx |
| Ozone (trioxygen) | O3 | Thioredoxin | Trx |
| Organic hydroperoxide | ROOH | Peroxiredoxin | Prx |
| Hypochlorous acid | HOCl | Sulfiredoxin | Srx |
| Peroxynitritea | ONOO− | Phytochemicals | |
| Vitamins A, C, E | |||
| Ceruloplasmin |
a
Actually a reactive nitrogen species.
ROS, reactive oxygen species; RNS, reactive nitrogen species.