Background: Phospholipids are widely used in food and pharmaceutical industry as functional excipients. In spite of the many analytical methods reported, there are very limited reports concerning systematic research and comparison of phospholipid excipients.
Objective: To present a comprehensive evaluation of commercial natural phospholipid excipients (CNPEs).
Methods: Seventeen batches of CNPEs from five manufacturing enterprises, isolated either from soybean or egg yolk, were investigated. The content and composition of phospholipids, fatty acids and sterols as a whole were considered as the evaluative index of CNPEs. Eight kinds of phospholipids were determined by Supercritical Fluid Chromatography (SFC), twenty-one kinds of fatty acids were determined by Gas Chromatography (GC) after boron trifluoride-methanol derivatization, and nine kinds of sterols were determined by High Performance Liquid Chromatography (HPLC) after separation and derivatization of the unsaponifiable matter. Cluster analysis was employed for the classification and identification of the CNPEs.
Results: The results showed that each kind of CNPEs had its characteristic content and composition of phospholipids, fatty acids and sterols. Seventeen batches of samples were divided into eight groups in cluster analysis. CNPEs of the same type from different source (soybean or egg yolk) or enterprises presented different content and composition of phospholipids, fatty acids and sterols.
Conclusion: Each type of CNPEs had its characteristic content and composition of phospholipid, fatty acid and sterol. The compositions of phospholipid, fatty acid and sterol as a whole can be applied as an indicator of the quality and characteristics for CNPEs.
Keywords: Natural phospholipid, phospholipids, fatty acids, sterols, supercritical fluid chromatography, hierarchical cluster analysis.