H-1-NMR STUDIES OF THE OZONATION OF METHYL OLEATE

Unsaturated fatty acids are one of tt-le main constituents of cellular membrane phospholipids and the aspect of ozonation of unsaturated fat ty acids has been widely studied by different authors. We here study t he ozonolysis of methyl oleate with addition of water or ethanol as a model to explore the efficiency of the H-1-NMR technique for the detec tion of Criegee ozonides in order to use it to follow up ozone therapy . It was found that ozonation of methyl oleate in the presence of wate r or ethanol produces ozonation products observed by H-1-NMR depending on ozone doses. The intensity of the H-1-NMR signals of Criegee ozoni des increases with incremented ozone doses, however they appeared at l ower ozone doses in water than in ethanol. Signals from aldehydes were also detected but at lower doses in ethanol than in water. These resu lts suggest that the H-1-NMR technique is an efficient alternative met hod to evaluate Criegee ozonides produced upon ozonization of unsatura ted fatty acids. The reaction mechanism for the ozone reaction with un saturated fatty acids in the presence of water or ethanol is analyzed.