FATTY-ACIDS IN MARINE MACROALGAE FROM SOUTHERN YEMEN (HADRAMOUT) INCLUDING OCCURRENCE OF EICOSATETRAENOIC (20/4) AND EICOSAPENTAENOIC (20/5) ACIDS

Twenty macroalgae belonging to the Chlorophyta, Phaeophyta and Rhodophyta were collected from the Hadramout coast, and samples were subsequently analysed for their lipids. All samples of algae had broadly similar lipid compositions, but with quantitative differences. The predominant saturated fatty acid in all the algae was palmitic acid (16:0). The Phaeophyta and Rhodophyta were, as a rule, richer than the Chlorophyta in eicosatetraenioc (20:4) and eicosapentaenoic (20:5) acids, but poorer in linolenic (18:3) acid. These polyunsaturated fatty acids occurred at high levels in monogalactosyldiacylglycerols (MGDG) and digalactosyldiacylglycerols (DGDG) in the Phaeophyta and the Rhodophyta, but not in those of the Chlorophyta where the MGDG and DGDG were rich in linolenic (18:3) and hexadecatrienoic acid (16:3).