Ultra-violet Photolysis of Unsaturated Fatty Acids in Relation to the Thiobarbituric Acid Test

A CHARACTERISTIC pink coloration was observed by Kohn and Liversedge 1 after heating tissue suspensions with aqueous thiobarbituric acid (TBA). Colour formation was attributed to reaction of unknown oxidation products of unsaturated fatty acids 2 . The principal TBA-reactive substance is considered to be malonaldehyde 3,4 . However, the means of formation of malonaldehyde is unknown. Inasmuch as ultra-violet irradiation of unsaturated fatty acids had been used to produce TBA-reactive products 5 , investigation of the radiation-induced oxidation was conducted in this work in an attempt to clarify the basis of the TBA test.