ANALYSIS OF EPOXY FATTY-ACIDS BY GC-MS OF THEIR 4,4-DIMETHYLOXAZOLINEDERIVATIVES

The derivatization of fatty acids with different functional groups to their 4,4-dimethyloxazoline (DMOX) derivatives proved to be a reliable method for their mass spectrometrical identification. Now DMOX deriva tives of different epoxy fatty acids were tested: saturated mono and d iepoxy fatty acids, mono and double unsaturated epoxy fatty acids and an hydroxy epoxy fatty acid. The EI-MS spectra of all of the analysed epoxy fatty acids enable correct assignments of the epoxy group positi ons, furthermore of the C-C double bond in monoepoxy-monoenoic acids a nd of the hydroxy group position. In the case of the other unsaturated epoxy fatty acids the intensities of the indicative peaks for the dou ble bonds were not intense enough to allow unequivocal assignments, ho wever. Finally three epoxy fatty acids could bc identified in autoxidi zed soybean and linseed oils.