Extraction and detailed characterization of phospholipid-enriched oils from six species of edible clams

Abstract

Phospholipid (PL)-enriched oils were recovered from six species of edible clams, namely Cyclina sinensis, Mactra chinensis Philippi, Mactra veneriformis Reeve, Meretrix meretrix, Ruditapes phliippinarum and Saxidomus purpurata, using a mixture of ethanol and hexane (1:1, v/v). The oils contained a high proportion of polyunsaturated fatty acids (PUFA) (26.78-45.36% of total FAs), especially eicosapentaenoic acid (EPA) (8.17-10.48% of total FAs) and docosahexaenoic acid (DHA) (7.83-21.34% of total FAs). The oils also contained a high percentage of PL (39.86-74.05% of total lipids). Among PL, phosphatidylcholine (37.40-52.19mol%) and phosphatidylethanolamine (34.74-43.10mol%) were dominant. At least 435, 442, 513, 438, 433 and 437 glycerophospholipid (GP) molecular species were characterized, respectively, in lipids from Cyclina sinensis, Mactra chinensis Philippi, Mactra veneriformis Reeve, Meretrix meretrix, Ruditapes phliippinarum and Saxidomus purpurata. Most of the predominant GP molecular species contained PUFA, mainly EPA and DHA, indicating that clam is a potential resource of PUFA enriched GP.

Keywords: Clam; HPLC-ESI-MS/MS; Lipid class composition; Molecular species; Phospholipid class composition.