1-O-ALK-1'-ENYL-2-ACYL-GLYCEROPHOSPHOETHANOLAMINE CONTENT AND MOLECULAR-SPECIES COMPOSITION IN FISH BRAIN

Ethanolamine glycerophospholipids from the brains of both trout and cod comprised 36-38% of 1-O-alk-1'-enyl-2-acyl-glycerophosphoethanolamine (GPE) determined using two methods. In 1-O-alk-1'-enyl-2-acyl-GPE from trout brain, the main molecular species were, 18:1a/18:1, 18:0a/18:1 and 16:0a/18:1, which totalled 63.3%, while polyunsaturated fatty acid (PUFA) containing species totalled only 18.2%. 1-O-Alk-1'-enyl-2-acyl-GPE from cod brain was much more unsaturated with PUFA containing species totalling 52.6%, of which 18:0a/20:5n-3,18:1a/20:5n-3 and 18:1a/22:6n-3 were predominant. In cod 18:1a/18:1, 18:0a/18:1 and 16:0a/18:1 were the only other species present at over 5% each, totalling 31.8%. In both cod and trout, small amounts of species containing 22:4n-6 were found. The results of this and earlier studies indicate that there is considerable specificity of composition at the level of molecular species between different lipid classes and subclasses.