Institute of Soil and Water Resources and Environmental Science, College of Environmental and Resource Sciences, Zhejiang University, Hangzhou 310058, China.
J Hazard Mater. 2024 Dec 5;480:135875. doi: 10.1016/j.jhazmat.2024.135875. Epub 2024 Sep 17.
Selenium-enhanced arsenic uptake by As-hyperaccumulators Pteris vittata and Pteris cretica is known, but how it impacts antimony (Sb) uptake and associated mechanisms are unclear. Here, we investigated the effects of 2.5 μM selenate (Se) on Sb uptake by two plants after growing for 10 days under hydroponics containing 10 or 50 μM antimonate (SbV) (Sb or Sb). Both plants were efficient in taking up SbV, which was reduced to SbIII (17-40 %) and mainly accumulated in the roots (86-97 %). The addition of Se increased the Sb contents by 78-97 and 29-33 % to 242-1358 and 132-697 mg kg in P. vittata and P. cretica roots. Compared with the Sb and Sb treatments, addition of Se increased the SbV reduction, with more increase in P. vittata than P. cretica roots (181-273 % vs. 17-29 %). Enhanced GSH-GSSG cycle mediated by glutathione peroxidase (GPX) and glutathione reductase (GR) may play an important role in SbV reduction in the roots. Compared with the Sb treatments, addition of Se increased the GPX and GR activity by 71-97 and 2-50 % in P. vittata roots, and 59-153 and 22-63 % in P. cretica roots. Besides, Se upregulated the expression of arsenate reductases PvHAC1 and PvACR2 in P. vittata roots by 1.7-3.4 folds but not in P. cretica. Se-enhanced SbV reduction in P. vittata explains why it was more effective in Sb accumulation than P. cretica. Taken together, Se is effective in increasing the Sb uptake in both plants probably by promoting SbV reduction via GSH-GSSG cycle and/or PvHAC1/PvACR2, suggesting that Se may be used to enhance phytostabilization of Sb-contaminated soils.
硒增强蜈蚣草和凤尾蕨对砷的吸收是已知的，但它如何影响锑（Sb）的吸收及其相关机制尚不清楚。在这里，我们研究了在水培中添加 2.5 μM 硒酸盐（Se）对两种植物在含有 10 或 50 μM 锑酸盐（SbV）（Sb 或 Sb）条件下生长 10 天后 Sb 吸收的影响。两种植物都有效地吸收 SbV，SbV 被还原为 SbIII（17-40%），主要积累在根部（86-97%）。添加 Se 将 Sb 含量分别提高了 78-97%和 29-33%，达到 242-1358 和 132-697 mg kg 在蜈蚣草和凤尾蕨的根部。与 Sb 和 Sb 处理相比，添加 Se 增加了 SbV 的还原，在蜈蚣草根中比凤尾蕨根增加更多（181-273%比 17-29%）。谷胱甘肽过氧化物酶（GPX）和谷胱甘肽还原酶（GR）介导的增强的 GSH-GSSG 循环可能在根部 SbV 的还原中发挥重要作用。与 Sb 处理相比，添加 Se 使蜈蚣草根中的 GPX 和 GR 活性分别增加了 71-97%和 2-50%，在凤尾蕨根中增加了 59-153%和 22-63%。此外，Se 在蜈蚣草根中上调了砷酸盐还原酶 PvHAC1 和 PvACR2 的表达，分别增加了 1.7-3.4 倍，但在凤尾蕨根中没有。Se 增强了蜈蚣草对 SbV 的还原，这解释了为什么它比凤尾蕨更有效地积累 Sb。总的来说，Se 有效地增加了两种植物对 Sb 的吸收，可能是通过 GSH-GSSG 循环和/或 PvHAC1/PvACR2 促进 SbV 的还原，这表明 Se 可用于增强 Sb 污染土壤的植物稳定化。
