Intra-and interspecific variability of fatty acid composition of soft corals

The intra-and interspecific variability of fatty acid (FA) composition of soft corals was examined in the tropical alcyonarian Sarcophyton sp., tropical gorgonian Euplexaura erecta , and boreal alcyonarian Gersemia rubiformis . Characteristic significant differences in the FA composition were found between these species belonging to different taxonomic groups and habitats. We assume that the FA groups 14: 0 + 16: 0 + 18: 3n-6, 16: 2 + 20: 4n-6 + 24: 5n-6, and 18: 1n-7 + 20: 1n-7 + 20: 5n-3 + 24: 6n-3 are characteristic of Sarcophyton sp., E. erecta , and G. rubiformis respectively. There were no significant differences ( p > 0.05) between the three soft coral species in the content of oleic, linoleic, and docosahexaenoic acids. The relative content of more than 45% of individual FA did not significantly differ ( p > 0.05) between the pairs of species, i.e., intraspecific variations exceeded interspecific ones. The reasons for intraspecific variability of soft coral FA composition are discussed. Control of this variability is needed when using individual FA as chemotaxonomic and food markers.