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

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 (37.40–52.19   mol%) and phosphatidylethanolamine (34.74–43.10   mol%) 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.