Identification of very-long-chain polyunsaturated fatty acids from Amphidinium carterae by atmospheric pressure chemical ionization liquid chromatography-mass spectroscopy.

A method is described for the enrichment of very-long-chain polyunsaturated fatty acids (VLCPUFAs) from total fatty acids of Amphidinium carterae and their identification as picolinyl esters by means of microbore liquid chromatography-mass spectrometry with atmospheric pressure chemical ionization (LC-MS/APCI). The combination of argentation TLC and LC-MS/APCI was used to identify unusual VLCPUFAs up to hexatriacontaoctaenoic acid. Two acids, 36:7n-6 and 36:8n-3, were also synthesized to unambiguously confirm their structure. The possibilities of VLCPUFAs biosynthesis are proposed.