Copper‐catalysed oxidation of linoleic acid in buffered aqueous solutions. I—Effect of ascorbic acid

Abstract

Abstract Ascorbic acid at a concentration of 10 −3 M was a more effective pro‐oxidant in the presence of low copper concentrations than at high concentrations, particularly in the initial stages of oxidation or in the lower pH range (5·5–4·7). This suggested a much more complex role for ascorbic acid than that of copperreducing agent. Reaction of the ascorbic acid radical with oxygen and consequent formation of free HO' radicals was considered to be the most likely initiation reaction resulting from the oxidation of ascorbic acid to dehydroascorbic acid by copper. Dehydroascorbic acid was also found to be an effective pro‐oxidant in the presence of copper.