FATTY ACID COMPOSITION AND UTILIZATION IN DEVELOPING EGGS OF SOME MARINE NUDIBRANCHS (MOLLUSCA: GASTROPODA: OPISTOBRANCHIA) FROM SOUTHWEST SPAIN

Abstract The fatty acid composition of whole egg masses was investigated in 4 marine nudibranchs collected from the southwest of Spain: Polycera aurantiomarginata, Polycera quadrilineata, Berghia columbina and Berghia verrucicornis. The four species are carnivorous. All nudibranchs were characterized by high levels of n-3 polyunsaturated fatty acids (n-3 PUFA), mainly eicosapentaenoic acid (20:5n-3), docosapentaenoic acid (22:5n-3) and docosahexaenoic acid (22:6n-3). Other major fatty acids were the saturated palmitic (16:0) and stearic (18:0) acids, the monounsaturated oleic acid (18:1n-9) and the n-6 PUFA arachidonic (20:4n-6) and docosatetraenoic (22:4n-6) acids. Relative high percentages of the plasmalogen derivatives 16:0DMA and 18:0DMA were also detected. Univariate analysis showed that egg fatty acids from P. aurantiomarginata and P. quadrilineata significantly differed from those of B. columbina and B. verrucicornis. Higher levels of saturated fatty acids and 22:6n-3 and lower percentages of 18:0D...