Identification and occurrence of a novel cis-4,7,10,trans-13-docosatetraenoic fatty acid in the scallop Pecten maximus (L.)

A new fatty acid isolated from the scallop Pecten maximus was determined to be a 22:4 geometrical isomer [Delta 4?,7?,10?,13?] (X) using GC-MS analysi s of the 2-alkenyl-4,4-dimethyloxazoline derivative. The number of trans do uble bonds was determined on silver ion HPLC by comparison with the mono-tr ans geometrical isomers of 22:4[Delta 4cis,7cis,10cis,13cis] (S), obtained through partial hydrazine reduction of all-cis-22:6(n-3) followed by a p-to luenesulfinic isomerization of the derivatives. Comparing the trienes obtai ned through partial hydrazine reduction of (X) and (S) determined a cis-4,7 ,10,trans-13-docosatetraenoic fatty acid. This fatty acid has not been repo rted previously in any organisms and is believed to be specific to the pect inid family. (C) 1999 Elsevier Science B.V. All rights reserved.