Department of Environmental Engineering, University of Seoul, Seoul, Republic of Korea.
Ecotoxicol Environ Saf. 2019 Nov 15;183:109496. doi: 10.1016/j.ecoenv.2019.109496. Epub 2019 Jul 31.
Iron nanoparticles (NPs) are widely used for the removal of arsenic from water. In this study, we evaluated the interaction between arsenate (AsO) and FeO-NPs on early seedling growth of Vigna radiata. Seedlings were raised in AsO and FeO-NPs, alone and in combination. While FeO-NPs slightly promoted seedling growth, AsO reduced seedling growth drastically. AsO-induced decline in the seedling growth was recovered by FeO-NPs. In contrast, equivalent concentrations of FeCl, alone and together with AsO, inhibited seed germination completely. Lower arsenic content in seedlings raised in the presence of FeO-NPs indicated that FeO-NPs restricted arsenic uptake. Ability of FeO-NPs to restrict the arsenic uptake of the seedlings was due to adsorption of AsO, as revealed by transmission and scanning electron microscopy. Non-toxic levels of iron in seedlings were due to restriction of FeO-NPs to root-surface. AsO enhanced the ferric chelate reductase activity of root which was recovered by FeO-NPs. The AsO-induced oxidative stress, evident from high levels of proline, HO and malondialdehyde, and lowered root oxidisability was ameliorated by FeO-NPs. AsO-induced enhancement in total antioxidant capacity, superoxide dismutase and catalase activity, and decline in guaiacol peroxidase activity were antagonized by FeO-NPs. Our findings reveal that FeO-NPs provide effective resistance/amelioration to arsenic toxicity by reducing arsenic availability to plants.
铁纳米粒子（NPs）被广泛用于从水中去除砷。在这项研究中，我们评估了砷酸盐（AsO）与 FeO-NPs 之间的相互作用对豇豆早期幼苗生长的影响。幼苗在 AsO 和 FeO-NPs 单独或联合存在的情况下进行培养。虽然 FeO-NPs 略微促进了幼苗生长，但 AsO 却大幅抑制了幼苗生长。FeO-NPs 恢复了 AsO 诱导的幼苗生长下降。相比之下，同等浓度的 FeCl，单独和与 AsO 一起，完全抑制了种子发芽。在存在 FeO-NPs 的情况下培养的幼苗中砷含量较低，表明 FeO-NPs 限制了砷的吸收。FeO-NPs 限制幼苗砷吸收的能力归因于 AsO 的吸附，这一点通过透射和扫描电子显微镜得到了证实。幼苗中低毒水平的铁是由于 FeO-NPs 限制了根表面的铁。AsO 增强了根中的铁螯合还原酶活性，而 FeO-NPs 则恢复了该活性。AsO 诱导的氧化应激，表现为脯氨酸、HO 和丙二醛水平升高，根氧化能力降低，都被 FeO-NPs 改善了。AsO 诱导的总抗氧化能力、超氧化物歧化酶和过氧化氢酶活性增强，以及愈创木酚过氧化物酶活性下降，都被 FeO-NPs 拮抗了。我们的发现表明，FeO-NPs 通过降低砷对植物的有效性，为砷毒性提供了有效的抗性/缓解作用。
