Optimizing the Timeframe to Produce Polychaetes (Hediste diversicolor) Enriched With Essential Fatty Acids Under Different Combinations of Temperature and Salinity

Polychaetes can be successfully employed to recover essential fatty acids (EFA) from wasted uneaten aquafeeds present in aquaculture effluents. The optimization of the timeframe required produce premium ragworms ( Hediste diversicolor ) biomass rich EFA is paramount make available industry another alternative ingredient fish meal and oil. study aimed evaluate potential enrichment acid (FA) profile when fed a commercial aquafeed during 10, 20, 40 days (D10, D20, D40) under different combinations water temperature (20 25°C) salinity (15, 25). Total FA incremented progressively overtime, with D40 polychaetes exhibiting average values ranging between 70 90 μg mg –1 DW. n -6 ranged 13 17 DW, while that -3 varied 19 DW at D40. No significant differences were found H. cultured salinity. exhibited 28 31% dissimilarity wild conspecifics displayed higher content two FA: eicosapentaenoic (20:5 -3, EPA) docosahexaenoic (22:6 DHA) (values 9.6–11.2% 4.3–5.0% total FA, respectively). A similarity was recorded than initially stocked or specimens. Palmitic (16:0), oleic (18:1 -9), linoleic (18:2 -6), eicosadienoic (20:2 EPA -3), DHA -3) whose concentration highest increment. Evidence de novo biosynthesis observed through formation some neither biomass, nor supplied, such as 5,11-eicosadienoate Δ 5,11 20:2), 7,13,16-docosatrienoate 7,13,16 22:3), dihomo-gamma-linolenic (20:3 eicosatrienoic eicosatetraenoic (20:4 acids. plateau -6, not reached over period. Overall, highlights an extractive species for integrated multi-trophic (IMTA) applications.