Thin-layer chromatographic separation of dimethylphosphatidates derived from lecithins.

The separation of lecithin derivatives based on their fatty acid substituents has been investigated. Several synthetic and natural lecithins were converted to their corresponding dimethylphosphatidates by hydrolysis with phospholipase D (phosphatidylcholine phospholipase D (phosphatidylcholine phosphatidohydrolase, EC 3.1.4.4) and methylation of the resulting phosphatidic acids with diazomethane. These dimethylphosphatidates were separated into fractions by reversed-phase thin-layer chromatography. Separations were dependent on the total number of methylene groups and double bonds in the two fatty acid chains. Fractionated dimethylphosphatidates were extracted from the plates and fatty acids were determined.