ESR spin-trapping studies of influence of phenolic compounds on hydroxyl radical formation

Abstract

The influence of some phenolic compounds, such as catechol, pyrogallol, resorcinol, vanillin, salicylic acid and 5-aminosalicylic acid, on the hydroxyl radical formation was studied by electron spin resonance (ESR) using the spin trapping method. The results of the investigation show that phenolic compounds, which possess a catechol residue, enhance the formation of the hydroxyl radical during the oxido-reductive reactions of ferric compound, a thylendiaminotetraacetic acid with hydrogen peroxide in sodium phosphate buffer at pH 7.4. The ferric ions are reduced by the phenolic compounds forming ferous ions which react with the hydrogen peroxide in a Fenton type reaction and increase the concentraton of hydroxyl radicals.