Melanins are considered to be natural photoprotectors in the melanocytes and keratinocytes
of the skin. These pigments have also been suggested to play an important role in protection …

The human skin and eye melanin is commonly viewed as an efficient photoprotective agent.
To elucidate the molecular mechanism of the melanin-dependent photoprotection, we …

Human skin exhibited a stable electron spin resonance (ESR) signal before irradiation, only
if the samples were pigmented. The single almost symmetrical absorption peak with g …

The known photoreactions of melanin include production of melanin free radicals and
oxygen consumption. While qualitative descriptions of the intermediates and products of …

Throughout the body, melanin is a homogenous biological polymer containing a population
of intrinsic, semiquinone-like radicals. Additional extrinsic free radicals are reversibly photo …

Bleaching of eumelanin has been studied in model systems consisting of synthetic dopa-
melanin and various concentrations of hydrogen peroxide, molecular oxygen, and copper …

The polyquinoid nature of eumelanin (s) enables them to couple oxidation of electron
donors with the reduction of electron acceptors. We have studied the ability of synthetic …

Abstract The unstable quinones of 3, 4-dihydroxyphenylalanine (dopa) and the most
abundant cysteinyldopa isomers (2S-, 5S-and 2, 5S, S′-) have been generated rapidly via …

Rose Bengal is shown to photosensitize free‐radical production and oxygen consumption in
solutions of melanin from autooxidation of 3, 4‐dihydroxyphenylalanine (DOPA). In …

Publisher Summary Melanins contain free radicals under all known experimental conditions.
The free-radical content is sensitive to light, reducing and oxidizing equivalents, and other …