The hydroxyl free radical reactions of ascorbyl palmitate as measured in various in vitro models

The OH. free radical scavenging properties of ascorbyl palmitate (AP), water-solubilized in the presence of a surfactant (Brij 35), were tested in various systems: (1) The inhibition of polymerization of bovine serum albumin by OH. free radicals generated by the Fenton reaction indicated AP exerts a considerable protective effect against polymerization by scavenging the OH. free radicals. (2) ESR spin trapping comparisons of DMPO with AP were conducted. Using the Fenton reaction as a source of OH. free radicals, AP was 1 order of magnitude faster in scavenging these radicals than DMPO. (3) Oxidative modification of BSA by Co-60-gamma irradiation of 80 krad, results in a strong increase in protein carbonyl content. AP inhibits carbonyl formation very efficiently, indicating that AP may be utilized as a biological OH. free radical scavenger in human therapy. (C) 1999 Academic Press.