Anatomical distribution of sterols and fatty acids in the bivalve Mactra chinensis

he sterol and fatty acid profiles in the bivalve Mactra chinensis were investigated for the hepatopancreas, gonad, mantle, gill, adductor muscle, and remainder. In all the organs and tissues, the major sterols were cholesterol (31.8-42.4%of total sterols), 24-methylcholesta-5, 22-dienol (17.5%), 24-methylenecholesterol (10.2-19.8%), cholesta-5, 22E-dienol (8.0-11.8%), and 24-methylcholest-5-enol (2.0-7.6%).The distribution of these sterols in the bivalve appeared to be uniform among the organs and tissues examined. This suggests that dietary sterols are not preferentially assimilated by this bivalve. The fatty acid profile of the hepatopancreas bore a resemblance to that of the gonad but differed from those of other organs and tissues. In the females, the hepatopancreas and gonad contained higher proportions of 14:0 and 20:5ω3 and lower proportions of 22:6ω3 than other organs and tissues.