Phospho- and phosphonolipids of the aegean pelagic scyphomedusa Pelagia noctiluca

Abstract

The total lipid content found in Pelagia noctiluca (0.19% of the whole-body weight) is comparable to that reported for other stinging jellyfish species. Its polar lipid components were found to represent 26.2% of the total lipids and to contain 75.7% glycerophospholipids and 24.3% sphingophosphonolipids. The individual lipid classes obtained by column Chromatographic fractionation were purified by preparative TLC, and their structure was confirmed by a combination of Chromatographic and analytical determinations before and after mild alkaline hydrolysis or dry acid methanolysis, and by IR analysis. The overall composition of the polar lipids was: cardiolipin, 9.1%; phosphatidylethanolamine, 24.8% (of which 55% was glyceryl ether analog); phosphatidylcholine, 36.3% (of which 62% was glyceryl ether analog); lysophosphatidylethanolamine and lysophosphatidylcholine, 5.0%; ceramide aminoethylphosphonate, 21.0% plus 3.3% (another two minor species). Unsaturated fatty acyl groups represented about 52 and 33%, respectively, in phosphatidylethanolamine and phosphatidylcholine, while their glyceryl ether analogs were found to contain about 41 and 91% unsaturated fatty alkyl chains, respectively (total unsaturation 49 and 51%, respectively). In contrast, saturated fatty acyl groups with 14–16 carbon atoms were almost exclusive components (about 96%) of the major ceramide aminoethylphosphonate species.