Analysis of cereal digalactosyldiacylglycerol molecular species by high-performance liquid chromatography

An optimized procedure for the high-performance liquid chromatographic resolution of molecular species of digalactosyldiacylglycerols from cereals has been developed. The optimal conditions were found by a three-step optimization strategy by taking eluent composition, eluent profile, system temperature, and flow into consideration. Separation of seven molecular species was achieved for oats and wheat-kernel digalactosyldiacylglycerols. Molecular species with the same partition number were eluted in the order of increasing unsaturation when utilizing eluent systems based on alcohols and water. This is reversed as compared to what is found when using eluent systems that contain acetonitrile, in which the elution order of the molecular species with the same partition number is according to decreasing unsaturation.