Hisako Shiina

On the structure of highly unsaturated fatty acids of fish oils by high resolution nuclear magnetic resonance spectral analysis

Methyl esters of highly unsaturated fatty acid concentrates were prepared from fish oils by the urea-adduct method. The nuclear magnetic resonance spectra of the mixed esters and some related pattern compounds were analyzed. As a result, it was concluded that the structure of highly unsaturated fatty acids has divinylmethane arrangement of the ethylenic bonds and no divinylethane arrangement, and that one methylene group is present between the terminal methyl group and the double bond located at the remotest position from a carboxyl group in the acids.