The production of selenium-enriched fish can contribute to alleviating selenium deficiency in human diets. However, it is still unclear which selenium source, as an additive, can efficiently and cost-effectively produce high-quality selenium-enriched fish. This study evaluated the effects of selenium nanoparticles (SeNP), selenite, and selenomethionine (SeMet) on the growth, antioxidant capacity, selenium content, selenium speciation, and meat quality of grass carp. Ten diets were prepared, including a basal diet (BD) and three concentrations (0.1, 0.3, and 0.9 mg/kg) of SeNP, selenite, and SeMet. A total of 600 fish (250.79 ± 1.57 g) were randomly assigned to 30 tanks (3 tanks/group). Fish were fed the experimental diet three times daily for 60 d. In this study, SeNP most significantly promoted the growth and antioxidant capacity of grass carp, with 0.3 mg/kg SeNP identified as the optimal additive concentration. Additionally, SeNP demonstrated equally excellent bioavailability as SeMet and significantly increased the content of SeMet in grass carp () muscle. Furthermore, compared to SeMet and selenite, dietary SeNP could more significantly enhance the content of selenocysteine (SeCys) and methylselenocysteine (MeSeCys) in grass carp muscle tissue. In addition, we have demonstrated that SeCys and MeSeCys promote apoptosis of cancer cells (HeLa) through the mitochondrial apoptotic pathway (involving Bax and Bcl-2). Furthermore, as an additive, 0.3 mg/kg SeNP significantly improved the flesh quality of grass carp by reducing crude fat and heavy metal content, as well as increasing the levels of eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) and the ratio of n-3/n-6 polyunsaturated fatty acid (PUFA). In summary, SeNP is the most suitable additive for producing selenium-enriched fish.

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纳米硒在水产养殖中：生产富硒草鱼（Ctenopharyngodon idella）的独特优势

生产富硒鱼有助于缓解人类饮食中的硒缺乏症。然而，目前尚不清楚哪种硒源作为添加剂可以高效且经济地生产高质量的富硒鱼。本研究评估了纳米硒（SeNP）、亚硒酸盐和硒代蛋氨酸（SeMet）对草鱼生长、抗氧化能力、硒含量、硒形态和肉质的影响。准备了十种饮食，包括基础饮食（BD）和三种浓度（0.1、0.3 和 0.9 mg/kg）的 SeNP、亚硒酸盐和 SeMet。总共 600 条鱼（250.79 ± 1.57 g）被随机分配到 30 个水箱中（3 个水箱/组）。每天用试验饲料喂鱼 3 次，持续 60 天。本研究中，SeNP对草鱼生长和抗氧化能力的促进作用最为显着，确定0.3 mg/kg SeNP为最佳添加浓度。此外，SeNP表现出与SeMet同样优异的生物利用度，并显着增加了草鱼肌肉中SeMet的含量。此外，与SeMet和亚硒酸盐相比，饲料SeNP可以更显着地提高草鱼肌肉组织中硒代半胱氨酸（SeCys）和甲基硒代半胱氨酸（MeSeCys）的含量。此外，我们还证明 SeCys 和 MeSeCys 通过线粒体凋亡途径（涉及 Bax 和 Bcl-2）促进癌细胞（HeLa）凋亡。此外，0.3 mg/kg SeNP作为添加剂，通过降低粗脂肪和重金属含量，以及提高二十碳五烯酸（EPA）和二十二碳六烯酸（DHA）的含量和比例，显着改善草鱼的肉质。 n-3/n-6 多不饱和脂肪酸 (PUFA)。综上所述，SeNP是最适合生产富硒鱼的添加剂。