Polyunsaturated fatty acid metabolism in three fish species with different trophic level

Reducing the dependency of fishfeed for marine ingredients and species diversification are both considered crucial factors sustainable development aquaculture. The substitution fish oil (FO) by vegetable oils (VO) in aquafeeds is an economically feasible solution. However, such may compromise flesh content essential n-3 long chain polyunsaturated fatty acids (n-3 LC-PUFA) and, therefore, its nutritional value human consumption. Likewise, there a wide range strategies to select new target sector diversification, among which, capacity biosynthesize LC-PUFA from their C18 precursors abundant VO might be as fair preliminary strategy. Therefore, aim present study was analyze metabolic fate [1-14C] labeled 18:2n-6, 18:3n-3, 20:5n-3 22:6n-3 isolated hepatocytes enterocytes wild individuals three with different trophic level: herbivorous salema (Sarpa salpa), strict carnivorous sand sole (Pegusa lascaris) omnivorous thicklip grey mullet (Chelon labrosus). These were selected phylogenetic proximity consolidated farmed gilthead seabream (Sparus aurata), senegalese (Solea senegalensis), golden (Liza respectively. also assessed molecular cloning, functional characterization tissue distribution acyl elongase (Elovl) gene, elovl5, involved biosynthetic metabolism LC-PUFA. able docosahexaenoic acid (22:6n-3). S. salpa seems have similar than aurata, desaturase 2 (Fads2), ?6, ?8 ?5 activities. P. lascaris showed wider Fads2 activity repertory senegalensis, including ?4 residual ?6/?5 In C. labrosus, activities but not ?6 described L. aurata detected incubated cells. Elongation C20 C22 products occurred well Elovl5 heterologous expression yeast. specific pattern, highest rates observed liver, gut brain lascaris, labrosus. summary, biosynthesis salpa, labrosus greatly resembled that closer species. studied could further explored candidates aquaculture potential ability