Zhejiang Provincial Key Laboratory of Organic Pollution Process and Control, Department of Environmental Science, Zhejiang University, Hangzhou 310058, China.
Zhejiang Ecological Civilization Academy, Anji 313300, China.
Environ Sci Technol. 2024 Jun 25;58(25):11063-11073. doi: 10.1021/acs.est.4c03133. Epub 2024 Jun 13.
Rhizosphere iron plaques derived from Fe-based nanomaterials (NMs) are a promising tool for sustainable agriculture. However, the requirement for flooded conditions to generate iron plaque limits the scope of the NM application. In this study, we achieved Fenton oxidation of a highly chlorinated persistent organic pollutant (2,2',4,5,5'-pentachlorobiphenyl, PCB101) through iron plaque mediated by the interaction between α-FeO NMs and plant-rhizobacteria symbionts under dryland conditions. Mechanistically, the coexistence of α-FeO NMs and JD37 stimulated alfalfa roots to secrete acidic and reductive agents as well as HO, which together mediated the rhizosphere Fenton reaction and converted α-FeO NMs into iron plaque rich in Fe(II)-silicate. Further verifications reproduced the Fenton reaction using α-FeO NMs and rhizosphere compounds, confirming the critical role of •OH in the oxidative degradation of PCB101. Significant reductions in PCB101 content by 18.6%, 42.9%, and 23.2% were respectively found in stem, leaf, and soil after a 120-d treatment, proving the effectiveness of this NMs-plant-rhizobacteria technique for simultaneously safe crop production and soil remediation. These findings can help expand the potential applications of nanobio interaction and its mediated iron plaque generation for both agricultural practice and soil remediation.
根际铁斑块来源于基于铁的纳米材料（NMs），是可持续农业的有前途的工具。然而，生成铁斑块需要水淹条件，这限制了 NM 的应用范围。在这项研究中，我们通过α-FeO NM 与植物-根际共生菌之间的相互作用介导的铁斑块，在旱地条件下实现了高度氯化的持久性有机污染物（2,2',4,5,5'-五氯联苯，PCB101）的芬顿氧化。从机制上讲，α-FeO NM 和 JD37 的共存刺激了紫花苜蓿根分泌酸性和还原性物质以及 HO，它们共同介导了根际芬顿反应，并将α-FeO NM 转化为富含 Fe(II)-硅酸盐的铁斑块。进一步的验证使用 α-FeO NM 和根际化合物重现了芬顿反应，证实了•OH 在 PCB101 的氧化降解中的关键作用。经过 120 天的处理后，在茎、叶和土壤中分别发现 PCB101 的含量降低了 18.6%、42.9%和 23.2%，证明了 NM-植物-根际菌技术在安全作物生产和土壤修复方面的有效性。这些发现可以帮助扩展纳米生物相互作用及其介导的铁斑块生成在农业实践和土壤修复方面的潜在应用。
