Scavenger effect of vitamin E and derivatives on free radicals generated by photoirradiated pheomelanin

• Published in: Journal of pharmaceutical sciences 1995-01, Vol.84 (1), p.107-110
• Main Authors: Duval, C., Poelman, M. C.
• Format: Article
• Language: English
• Subjects: Animals; Biological and medical sciences; Cattle; Free Radical Scavengers; Free Radicals - chemistry; General and cellular metabolism. Vitamins; Medical sciences; Melanins - chemistry; Melanins - radiation effects; Pharmacology. Drug treatments; Photons; Superoxide Dismutase - blood; Vitamin E - analogs & derivatives; Vitamin E - pharmacology
• ISSN: 0022-3549; 1520-6017
• DOI: 10.1002/jps.2600840124

The free radical scavenger properties of vitamin E (DL‐α‐tocopherol), a natural antioxidant, and derivatives were studied using an original in vitro method consisting of free radical production by photoir‐radiation of pheomelanin and direct detection of the free radicals by a physical, specific technique, electron spin resonance. Validation of this method has been realized using well‐known biological free radical scavengers, superoxide dismutase and reduced glutathione. DL‐α‐Tocopherol, tocopheryl acetate, tocopheryl linoleate, and tocopheryl polyoxyethylene (POE) succinate induced a significant diminution of the free radical production. In order of efficiency, tocopheryl POE succinate was the best scavenger (37.6% inhibition at 0.25%) followed by tocopheryl linoleate (25.6% inhibition at 1%) and tocopheryl acetate (23.9%) inhibition at (0.5%) and finally DL‐α‐tocopherol (16.2% inhibition at 0.05%). The results reported a decrease of the inhibitory effect for high concentrations of DL‐α‐tocopherol (0.1%) and tocopheryl acetate (1%), showing a tendency of this compound to act as a prooxidant. Used in optimal concentrations in cosmetologic or dermatologic formulations, Vitamin E and these derivatives should prevent or reduce the harmful activity of free radicals in the skin.