Useful fatty acids in marine lipids as ingredient of functional foods

Abstract

Docosahexaenoic acid (DHA, 22:6 n-3) was characteristically the major fatty acid of all the major lipid classes of all organs of highly migratory fish species, such as Thunnus spp. The mean DHA content of the various organs accounted for more than 20% of the total fatty acids (TFA). These values differed markedly from the fatty acid profile of other fish species, because the fatty acid composition of other species is variable and the DHA content is less than 20% of TFA. In particular, the levels of DHA of the triacylglycerols (TAG) of all their organs comprised up to 20% of TFA, even though it is a neutral lipid. In contrast, the major fatty acids present in C. phaseoliformis lipids belong to the n-4 family non-methylene interrupted polyunsaturated fatty acids (NMI-PUFA): 20:3 n-4,7,15, 20:4 n-1,4,7,15, and 21:3 n-4,7,16, and two Bathymodiolus mussels contained high levels of methylene interrupted PUFA: 20:3 n-4,7,10, 20:4 n-1,4,7,10, and 21:3 n-4,7,10. Such special kinds of novel fatty acids are assimilated by symbiotic chemosynthetic bacteria, which use geothermal energy and minerals from the hydrothermal and cold-seep vents. Highly migratory fishes are a good dietary source of n-3 PUFA, such as DHA, and deep-sea bivalves have the possibility of synthesizing other physiologically active fatty acids. All marine animals might be good sources of such fatty acids as ingredients of functional foods.