Studies on Phospholipids. 9. The Composition of Rat-Liver Lecithins

It is well established that lipid fractions isolated from natural sources are not pure compounds even though they may be homogeneous with respect to the major analytical parameters. This is due to the presence of many molecular species differing only in the fatty acids esterified in the molecule. There is abundant evidence from experiments with [32p]_ phosphate that the several forms of, for example, lecithin are metabolically distinct This has also been demonstrated by using [14C]acetate, with respect to both phospholipids It is thus important that methods be developed for the complete determination of the composition of lipids, and the work presented below is a pre- liminary investigation of a possible procedure.