The action of hypochlorous acid on phosphatidylcholine liposomes in dependence on the content of double bonds. Stoichiometry and NMR analysis

Abstract

Kinetics of the consumption of hypochlorous acid in its reaction with double bonds of unsaturated phospholipids and fatty acids were measured using luminol chemiluminescence. Stoichiometry ratios between the consumption of HOC1/OC1⁻ and the loss of double bonds vary from 2:1 to 1:1. Hightst values were found in DMPC liposomes containing 5 mol% oleic acid or OPPC. With increasing content of double bonds or higher numbers of double bonds in a fatty acid acyl chain due to incorporated unsaturated fatty acids or phospholipids in DMPC liposomes the stoichiometry ratio falls continuously to 1:1. A ratio of about 1:1 was observed in multilamellar and unilamellar liposomes composed of egg yolk phosphatidylcholine. Products of the reaction of oleic acid with hypochlorous acid were analysed by ¹H-NMR spectroscopy. Chlorohydrins were formed in both DMPC liposomes containing 5 or 40 mol% oleic acid.