Tocopherol molecule

Vitamin E (α-tocopherol, α-Toc) is a lipophilic antioxidant in the body, derived from cereal, vegetables, vegetable oil and nuts.

α-Toc is known to inhibit the oxidative attack of free and membrane bound unsaturated fatty acid and interferes with the lipid peroxidation of melanocyte membranes. The vitamin is also able to scavenge free radicals including superoxide anions, hydroxyl radicals and singlet molecular oxygen. It can also act as a humectant. The depigmenting effect of α-Toc can further be attributed to an increase in intracellular glutathione and the inhibition of tyrosinase.

α-Tocopherol ferulate (α-TF) is a related compound, in which α-tocopherol is linked by an ester bond to ferulic acid, an antioxidant that stabilizes α-Toc. The presence of another antioxidant ferulic acid, causes a rapid regeneration of α-Toc and maintains a long lasting antioxidant effect.

A study completed investigating the biochemical effect of α-TF in human melanoma cells suggests the whitening effect is due to tyrosinase inhibition at the post-transcriptional level, possibly by an unidentified secondary molecule.