Lipid Material from Human Placenta

The method of countercurrent fractionation has been applied to the separation of a wide variety of substances. Among animal lipids, Lovern (1952) has studied ox-brain phospholipids, Lovern & Olley (1952) fractionated haddock-muscle lipids, while the lipids of human brain have been investigated by Cole, Lathe & Ruthven (1953). The latter study has now been extended to the lipid components of human placenta. The composition of placental lipids has been estimated previously by Pratt, Kaucher, Richards, Williams & Macy (1946) using ordinary chemical procedures. This work involves the assumption that the types of lipid found in placenta do not differ widely from those of brain, for which most of the analytical methods have been perfected. In the work now reported it has been found that in using the countercurrent method, lipid fractions obtained from placenta differ from those of brain. In particular, it seems impossible to account for the nitrogen and phosphorus contents of the placenta lipids on the basis of the types of phospholipid predominating in brain.