Selenium (Se) and zinc (Zn) are essential micronutrients that are often lacking in the diet of humans and animals, leading to deficiency diseases. Lemna and Azolla are two aquatic plants with a substantial protein content, which offer the possibility of utilizing them to remove Se and Zn from (waste)water while producing micronutrient-enriched dietary proteins and fertilizers. In this study, we explored interaction effects occurring between Se and Zn when these micronutrients are taken up by Azolla and Lemna. The two aquatic plants were grown on hydroponic cultures containing 0–5.0 mg/L of Se (Se(IV) or Se(VI)) and Zn. The Se and Zn content of the plants, growth indicators, bioconcentration factor (BCF) and Se/Zn removal efficiency from the water phase were evaluated. The results demonstrated that Se(IV) is more toxic than Se(VI) for both plant species, as evidenced by the remarkable decrease of biomass content and root length when exposed to Se(IV). Both aquatic plants took up around 10 times more Se(IV) than Se(VI) from the medium. Moreover, the Se accumulation and removal efficiency increased by 66–99% for Se(IV) and by 34–59% for Se(VI) in Lemna when increasing Zn dosage from 0 to 5.0 mg/L in the medium, whereas it declined by 13–26% for Se(IV) and 21–35% for Se(VI) in Azolla, suggesting a synergetic effect in Lemna, but an antagonistic effect in Azolla. The maximum BCF of Se in Lemna and Azolla were 507 and 667, respectively. The protein content in freeze-dried Lemna and Azolla was approximately 17%. The high tolerance and accumulation of Se and Zn in Lemna and Azolla, combined with their rapid growth, high protein content and transformation of inorganic to organic Se species upon Se(IV) exposure make Lemna and Azolla potential candidates for the production of Se(IV)- and Zn-enriched biomass that can be used as crop fertilizers or protein-rich food/feed supplements or ingredients. Accordingly, by growing the Azolla and Lemna on wastewater, a high-value product can be produced from wastewater while recovering resources.

硒和锌是人体和动物饮食中经常缺乏的必需微量营养素，会导致缺乏疾病。Lemna和Azolla是两种蛋白质含量较高的水生植物，它们可以利用它们从（废水）中去除Se和Zn，同时生产富含微量营养素的膳食蛋白质和肥料。在这项研究中，我们探讨了当微量元素被Azolla和Lemna吸收时，Se和Zn之间发生的相互作用。。两种水生植物都生长在含有0–5.0 mg / L的硒（硒（IV）或硒（VI））和锌的水培培养物中。评价了植物中硒和锌的含量，生长指标，生物富集因子（BCF）和水相中硒/锌的去除效率。结果表明，对于两种植物，Se（IV）的毒性都比Se（VI）高，这可以通过暴露于Se（IV）时生物量含量和根长显着降低来证明。两种水生植物从培养基中吸收的Se（IV）比Se（VI）多约10倍。此外，当培养基中锌的剂量从0增加到5.0 mg / L时，Lemna中Se（IV）的Se积累和去除效率提高了66–99％，Se（VI）增长了34–59％，而下降了通过在硒（IV）13-26％和21-35％硒（VI）满江红，提示在Lemna中具有协同作用，但在Azolla中具有拮抗作用。Lemna和Azolla中Se的最大BCF分别为507和667。冷冻干燥的Lemna和Azolla中的蛋白质含量约为17％。硒和锌在Lemna和Azolla中的高耐受性和积累，加上它们的快速生长，高蛋白含量以及暴露于Se（IV）后无机物向有机Se物种的转化，使Lemna和Azolla生产富含Se（IV）和Zn的生物质的潜在候选人，这些生物质可用作作物肥料或富含蛋白质的食品/饲料补充剂或成分。因此，通过在废水上培养满江红和Lemna，可以在回收资源的同时从废水中生产高价值的产品。