Tocopherols

Mechanism of action

Tocopherols are radical scavengers, delivering an H atom to quench free radicals. At 323 kJ/mol, the O–H bond in tocopherols is approximately 10% weaker than in most other phenols. This weak bond allows the vitamin to donate a hydrogen atom to the peroxyl radical and other free radicals, minimizing their damaging effect. The thus generated tocopheryl radical is relatively unreactive, but reverts to tocopherol by a redox reaction with a hydrogen donor such as vitamin C. As they are fat-soluble, tocopherols are incorporated into cell membranes, which are thus protected from oxidative damage.