Characterizing the phospholipid composition of six edible sea cucumbers by NPLC-Triple TOF-MS/MS

Abstract

An NPLC-Triple-TOF-MS/MS method was used to determine the composition of phospholipids (PLs) present within six sea cucumber species. The highest PL levels were obtained from the species Cucumaria frondosa (8.05 μmol/g). The method was capable of separating different PL classes as well as an ether-PL subclass from its diacyl counterparts. At least 295 molecular species from 7 PL classes were consistently detected in all sea cucumbers. The results indicated that sea cucumbers were rich in ether-PLs, especially 1-alkyl-2-acyl-phosphocholine and 1-alkenyl-2-acyl-phosphoethanolamine. The most dominant polyunsaturated fatty acids esterified to PLs were C20:5 and C20:4. All the sea cucumbers showed a high percentage of odd-chain fatty acids (OCFAs) that represented approximately 35–91 % of the total fatty acids. Furthermore, for the first time, rare phosphonoethanolamines were found in sea cucumbers. A heatmap model was established based on the phospholipid data that achieved a 100 % classification of the sea cucumbers.