Comparison of Selenium Metabolism in Three Brassicaceae Plants

Abstract

Although selenium (Se) is not an essential element in plants, Se metabolism in plants is remarkable, mainly for the purpose of phytoremediation and nutritional supplementation of Se. Brassica juncea (Indian mustard) is known as an Se accumulator. In addition to Indian mustard, unique Brassicaceae plants are consumed in Japan. Brassica rapa var. hakabura, commonly known as nozawana, and Brassica rapa var. peruviridis, commonly known as komatsuna, are typical Brassicaceae plants. In this study, we evaluated the Se-accumulating ability of these unique Brassicaceae plants. There were no significant differences in the Se concentrations in the roots and the leaves of the three Brassicaceae plants. However, nozawana most efficiently accumulated Se among the three Brassicaceae plants because it showed the most rapid growth, resulting in the highest biomass. Speciation revealed that the Se species accumulated in the three plants were identical. In addition, nozawana contained easily extractable essential minerals, such as iron, copper, and zinc. Potentialities of nozawana as a source of minerals and the phytoremediation of soil and water contaminated with Se were discussed.