Fe-Based Nanomaterials and Plant Growth Promoting Rhizobacteria Synergistically Degrade Polychlorinated Biphenyls by Producing Extracellular Reactive Oxygen Species

作者：Wu Ting, Yangzhi Liu, Tianying Zheng, Yunbu Dai, Zhongyu Li, Daohui Lin · 发表于：Environmental Science & Technology · 年份：2023 · DOI：10.1021/acs.est.3c02495 · 被引用次数：25 · 研究领域：Environmental remediation with nanomaterials、Nanoparticles: synthesis and applications、Subcritical and Supercritical Water Processes

Plant growth promoting rhizobacteria (PGPR) produce extracellular reactive oxygen species (ROS) to protect plants from external stresses. Fe-based nanomaterials can potentially interact with PGPR and synergistically degrade organic pollutants, yet they have received no study. Here, we studied how the interaction between a typical PGPR ( Pseudomonas chlororaphis, JD37) and Fe-based nanomaterials facilitated the degradation of 2,4,4′-trichlorobiphenyl (PCB28), by comparing the zerovalent iron of 20 nm (nZVI 20 ), 100 nm (nZVI 100 ), and 5 μm; iron oxide nanomaterials (α-Fe 2 O 3, γ-Fe 2 O 3, and Fe 3 O 4 ) of ca. 20 nm; and ferrous and ferric salts. Although all Fe materials (0.1 g L –1 ) alone could not degrade aqueous PCB28 (0.1 mg L –1 ) under dark or aerobic conditions, nZVI 20, nZVI 100, α-Fe 2 O 3, and Fe 2+ promoted PCB28 degradation by JD37, with the half-life of PCB28 shortened from 16.5 h by JD37 alone to 8.1 h with nZVI 100 cotreatment. Mechanistically, the nanomaterials stimulated JD37 to secrete phenazine-1-carboxylic acid and accelerated the NADH/NAD + conversion, promoting O 2 *– generation; JD37 increased Fe(II) dissolution from the nanomaterials, facilitating *OH generation; and the ROS gradually degraded PCB28 into benzoic acid through dihydroxy substitution, oxidation to quinone, and Michael addition. These findings provide a new strategy of nanoenabled biodegradation of organic pollutants by applying Fe-based nanomaterials and PGPR.