Interactions between reactive oxygen species and sulfhydryl groups of cysteine, acetylcysteine and glutathione.

Oxidative potencies of hydrogen peroxide, superoxide anions or hydroxyl radicals towards sulfhydryl groups of cysteine, acetylcysteine or glutathione were studied. Acetylcysteine was the least susceptible to oxidation by reactive oxygen species. The most vigorous oxidant of sulfhydryl groups was hydrogen peroxide.