Selenium is an essential micronutrient for humans, and seafood is one of the major selenium sources, as well as red meat, grains, eggs, chicken, liver and garlic. A substantial proportion of the total amount of selenium is present as selenium containing imidazole compound, selenoneine, in the muscles of ocean fish. In order to characterize the selenium content in seafood, the total selenium levels were measured in the edible portions of commercially important fish and shellfish species. Among the tested edible portions, alfonsino muscle had the highest selenium levels (concentration of 1.27 mg/kg tissue). High levels of selenium (1.20–1.07 mg/kg) were also found in the salted ovary products of mullet and Pacific herring. In other fish muscles, the selenium levels ranged between 0.12 and 0.77 mg/kg tissue. The selenium levels were closely correlated with the mercury levels in the white and red muscles in alfonsino. The selenium content in spleen, blood, hepatopancreas, heart, red muscle, white muscle, brain, ovary and testis ranged between 1.10 and 24.8 mg/kg tissue in alfonsino.
Yamashita, Y.; Yamashita, M. Identification of a novel selenium-containing compound, selenoneine, as the predominant chemical form of organic selenium in the blood of bluefin tuna. J. Biol. Chem. 2010, 285, 18134–18138, doi:10.1074/jbc.C110.106377.
Yamashita, Y.; Amlund, H.; Suzuki, T.; Hara, T.; Hossain, A.M.; Yabu, T.; Touhata, K.; Yamashita, M. Selenoneine, total selenium, and total mercury content in the muscle of fishes. Fish. Sci. 2010, 77, 679–686.
Kryukox, G.V.; Gladyshev, V.N. Selenium metabolism in zebrafish: Multiplicity of selenoprotein genes and expression of a protein containing 17 selenocysteine residues. Genes Cells 2000, 5, 1049–1060, doi:10.1046/j.1365-2443.2000.00392.x.
Yamashita, M.; Yamashita, Y.; Suzuki, T.; Kani, K.; Mizusawa, N.; Imamura, S.; Takemoto, T.; Hara, T.; Hossain, M.A.; Yabu, T.; Touhata, K. National Research Institute of Fisheries Science, Yokohama, Japan. Selenoneine, a novel selenium-containing compound, mediates detoxification mechanisms against methylmercury accumulation and toxicity in zebrafish embryo. Mar. Biotechnol. 2013. submitted.