Fluorometric determination of malonaldehyde in oxidized lipids.

Abstract
Malonaldehyde contents in oxidized lipid samples were determined fluorometrically by applying the reaction reported by Sawicki et al. (Anal. Chem., 35, 199 (1963)). This assay is based on the reaction of malonaldehyde with ethyl p-aminobenzoate in an acid medium, followed by treatment with alkaline dimethylformamide to afford fluorescence. Time course studies of the malonaldehyde contents in methyl linoleate, soybean oil and seasame oil oxidized by the active oxygen method showed that the contents increased and subsequently decreased with increasing oxidation time. The malonaldehyde contents were always lower than those estimated by means of the thiobarbituric acid method.