Studies of acetal phospholipides of brain. I. Procedure of isolation of crystallized acetal phospholipide from brain.

Feulgen and Rossenbeck (1) demonstrated in 1924 in the cytoplasm of cells the presence of substances which give histochemically a color reaction with Schiff’s aldehyde reagent. Feulgen and Voit (2) at the same time showed that the aldehyde group of these substances is not free, but bound in a labile form. The authors called this substance plasmalogen. Feulgen and Bersin (3) succeeded in 1939 in isolating this compound from beef muscle and identified it as an acetal of glycerylphosphorylcolamine. Feulgen’s method of isolation of this acetal phospholipide from muscle cannot be applied to tissues which contain a large amount of different lipides. Attempts to isolate an intact and pure acetal phospholipide from the lipide mixture of brain have been so far unsuccessful (4). In this paper a procedure is described, by which the isolation of a crystalline acetal phospholipide from brain can be achieved, and its physical and chemical properties are reported. The behavior of acetal phospholipide toward enzymes and the physiological significance of the fatty aldehydes are under investigation.