Elongation and desaturation of dietary fatty acids in turbot<i>Scophthalmus maximus</i> L., and rainbow trout,<i>Salmo gairdnerii</i> rich

Abstract

Turbot and rainbow trout, which had previously recieved diets free of fat, were fed [1-14C] fatty acids. The distribution of radioactivity in the tissue fatty acids was examined 6 days later. In rainbow trout fed [1-14C] 18:3omega3, 70% of the radioactivity was present in 22:6omega3 fatty acid. In contrast, turbot fed [1-14C] 18:1omega9, 18:2omega6, or 18:3omega3 converted only small amounts of labeled fatty acids (3-15%) into fatty acids of longer chain length. The major product of the limited modification found in turbot was the dietary acid elongated by 2 carbon atoms.