title: The effect of dietary methionine and white tea on oxidative status of gilthead sea bream (Sparus aurata).
abstract: Free radicals are continuously generated during an organism's lifetime. In order to understand the involvement in the oxidative status of fish, methionine and white tea were assayed as antioxidant supplements in diets for gilthead sea bream (Sparus aurata). For the purpose of this study, four isonitrogenous and isolipidic diets were formulated to contain 45 % of protein and 18 % lipid and 0·3 % methionine (Met diet), 2·9 % white tea dry leaves (Tea diet) and 2·9 % of white tea dry leaves + 0·3 % methionine (Tea + Met diet). An unsupplemented diet was used as the control. Key enzymatic antioxidant defences, superoxide dismutase (SOD) isoenzyme profile, total, reduced and oxidised glutathione and oxidative damage markers were determined. The results showed that dietary methionine supplementation increased liver SOD activity, while white tea induced higher hepatic catalase activity. Dietary white tea induced a notable increase in Mn-SOD isoenzyme. This is the first study to provide evidence that dietary tea inclusion in fish feeding could be an important source of Mn with metabolic repercussions on antioxidant mechanisms.
authors.affiliation: CIMAR/CIIMAR - Centro Interdisciplinar de Investigação Marinha e Ambiental, Universidade do Porto, Rua dos Bragas 289, Porto, Portugal. calaya@ugr.es
authors.forename: Amalia
authors.initials: A
authors.lastname: Pérez-Jiménez
authors.forename: Helena
authors.initials: H
authors.lastname: Peres
authors.forename: Vera
authors.initials: V
authors.lastname: Cruz Rubio
authors.forename: Aires
authors.initials: A
authors.lastname: Oliva-Teles
mesh_terms: D000821:Animal Feed / Q000009:adverse effects / Q000032:analysis*; D000818:Animals; D017756:Aquaculture; D015415:Biomarkers / Q000378:metabolism; D002374:Catalase / Q000378:metabolism; D005978:Glutathione / Q000378:metabolism; D007527:Isoenzymes / Q000378:metabolism; D015227:Lipid Peroxidation; D008099:Liver / Q000201:enzymology / Q000254:growth & development / Q000378:metabolism; D008345:Manganese / Q000009:adverse effects / Q000627:therapeutic use; D008715:Methionine / Q000009:adverse effects / Q000627:therapeutic use*; D010084:Oxidation-Reduction; D018384:Oxidative Stress; D010858:Pigmentation; D010936:Plant Extracts / Q000009:adverse effects / Q000627:therapeutic use*; D018515:Plant Leaves / Q000737:chemistry*; D021541:Sea Bream / Q000254:growth & development* / Q000378:metabolism; D013482:Superoxide Dismutase / Q000378:metabolism; D013662:Tea / Q000737:chemistry*; D015430:Weight Gain
chemical_list: D015415:Biomarkers; D007527:Isoenzymes; D010936:Plant Extracts; D013662:Tea; D008345:Manganese; D008715:Methionine; D002374:Catalase; D013482:Superoxide Dismutase; D005978:Glutathione