Behavior of Unsaturated Fatty Acids in the Thiobarbituric Acid Test after Radiolysis

Abstract

Following cobalt-60 gamma ray radiation or short were ultraviolet radiation the TBA-active products were separated from the exposed unsaturated fatty acid by thin-layer chromatography. The TBA-active sites of the chromatograms also reacted with benzidine, but did not react with KI. Similar patterns of spots were obtained with linolenic acid and with arachidonic acid using either irradiation process. However, the patterns obtained differed with the source of radiation. None of the spots obtained corresponded to that obtained with a reference sample of malonaldehyde, and evidence could not be obtained for the formation of malonaldehyde during the irradiation. While their production is accompanied by peroxide formation, the TBA-active compounds are carbonyl compounds, not of a peroxide nature. Increased absorption at 225 millimicrons parallels the production of TBA-active products during ultraviolet irradiation, but was not observed with gamma radiation.