Investigation of Natural Phosphatidylcholine Sources: Separation and Identification by Liquid Chromatography−Electrospray Ionization−Tandem Mass Spectrometry (LC−ESI−MS²) of Molecular Species

Abstract

This study is a contribution to the exploration of natural phospholipid (PL) sources rich in long-chain polyunsaturated fatty acids (LC-PUFAs) with nutritional interest. Phosphatidylcholines (PCs) were purified from total lipid extracts of different food matrices, and their molecular species were separated and identified by liquid chromatography−electrospray ionization−tandem mass spectrometry (LC-ESI−MS2). Fragmentation of lithiated adducts allowed for the identification of fatty acids linked to the glycerol backbone. Soy PC was particularly rich in species containing essential fatty acids, such as (18:2−18:2)PC (34.0%), (16:0−18:2)PC (20.8%), and (18:1−18:2)PC (16.3%). PC from animal sources (ox liver and egg yolk) contained major molecular species, such as (16:0−18:2)PC, (16:0−18:1)PC, (18:0−18:2)PC, or (18:0−18:1)PC. Finally, marine source (krill oil), which was particularly rich in (16:0−20:5)PC and (16:0−22:6)PC, appeared to be an interesting potential source for food supplementation with LC-PUFA−PLs, particularly eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA).