Improved Method for Determining Soybean Phospholipid Composition by Two-dimensional TLC-phosphorus Assay

Abstract

An improved microscale procedure for determining phospholipid composition by two-dimensional thin-layer chromatography (TLC) in conjunction with phosphorus analysis was established. For the quantitative determination of lipid phosphorus, an organic phosphate is converted to an inorganic phosphate by perchloric-nitrate digestion, which then made into an ammonium phosphomolybdate complex.Absorbance of the complex extracted with ethyl acetate/butyl acetate (9 : 1, vol/vol) was determined at 310 nm. A liner relationship between 0.051.00μg of phosphorus and absorbance was found.
This two-dimensional TLC method was carried out using synthesized P, P'-bis (1, 2-dihexadecylether-sn-glycerol-3-) -pyrophosphate as the internal standard. It was possible to analyze the phospholipid composition of soybean lecithin by this method using only 50μg of crude lipid extract.