12 13Selenium is recognized as an essential micronutrient for humans and animals. One of the main 14 sources of selenocompounds in the human diet is vegetables. Therefore, this study deals with the 15 Se species present in different edible sprouts grown in Se-enriched media. We grew alfalfa, lentil 16 and soy in a hydroponic system amended with soluble salts, containing the same proportion of 17 Se, in the form of Se(VI) and Se(IV). Total Se in the sprouts was determined by acidic digestion 18 in a microwave system and by ICP/MS. Se speciation was carried out by enzymatic extraction 19 (Protease XIV) and measured by LC-ICP/MS. The study shows that the Se content of plants 20 depends on the content in the growth culture, and that part of the inorganic Se was 21 biotransformed mainly into SeMet. These results contribute to our understanding of the uptake of 22 inorganic Se and its biotransformation by edible plants. 23 24

Research HighlightsSelenium species present in edible plants, grown in Se-enriched peat, are studied.Selcote Ultra® and selenium sodium salts are assayed to increase uptake of Se.Fortification with Se sodium salts increases Se content in plants.Plants biotransform inorganic Se mainly to SeMet.Contents over 10 mg Se kg -1 in peat can damage or inhibit plant growth.