Effect of the enrichment time with the tuna orbital oil emulsion on the fatty acids profile of juveniles of Artemia franciscana

Abstract Artemia is deficient in polyunsaturated fatty acids (PUFAs), particularly in arachidonic (ARA, 20:4n-6), eicosapentaenoic (EPA, 20:5n-3), and docosahexaenoic acid (DHA, 22:6n-3). The aim of this study was to determine the optimal time in which the higher contents of PUFAs in juveniles of Artemia franciscana were obtained by the effect of enrichment with the tuna orbital oil emulsion. Six enrichment periods were evaluated: 3, 6, 9, 12, 15 and 18 h, in addition to a control treatment (0 h). The most abundant fatty acids in A. franciscana were monounsaturated (43.10% ± 4.35 –52.92% ± 5.82%), followed by saturated (33.83% ± 1.71 –42.33% ± 2.31%) and PUFAs (8.86% ± 2.83% –21.32% ± 2.38%). ARA decreased over the enrichment time; the maximum content was 5.74 ± 0.37% at 3 h, which was not statistically different with respect to the content recorded at 0 h. The highest content of EPA was at 3 h (6.47% ± 1.44%), without significant differences with the content registered at 0 h, while that from 6 h and until 15 h tended to decrease significantly. At 6 h, the content of DHA (8.84% ± 2.72%) was significantly higher compared to the rest of the treatments, which did not differ among themselves, or with the control. After to the 6 h and until 15 h, the content of PUFAs tended to decrease, which could indicate the metabolization of them by A. franciscana, coupled with the possible oxidation of these fatty acids in the enrichment solution.