Positional distribution of 24∶6(n−3) in triacyl‐sn‐glycerols from flathead flounder liver and flesh

This paper presents the positional distribution of very long‐chain fatty acids, 24∶6(n−3), in triacyl‐ sn ‐glycerols (TG) of flathead flounder ( Hippoglossoides dubius ). Each of the liver and flesh TGs was subjected to the stereospecific analysis. The liver TGs contained 24∶6(n−3) at concentrations of 1.5, 1.2 and 1.7 mole % in the sn ‐1, sn ‐2 and sn ‐3 positions, respectively, and the flesh TGs had 9.0, 7.8 and 7.1 mole % in the sn ‐1, sn ‐2 and sn ‐3 positions, respectively. This fatty acid was distributed almost evenly among the three positions of the TGs. No preference for the sn ‐2 position was observed in contrast to the general tendency for the distribution of longer‐chain polyunsaturated fatty acids, such as 22∶6(n−3), 22∶5(n−3) and 20∶5(n−3). There was essentially no difference in the positional distributions of the liver and flesh TGs. The results obtained in this study give new fundamental information to the investigation of very long‐chain fatty acids.