Key Laboratory of Groundwater Circulation and Evolution, Ministry of Education, School of Water Resources and Environment, China University of Geosciences Beijing, Beijing 100083, China.
Key Laboratory of Groundwater Circulation and Evolution, Ministry of Education, School of Water Resources and Environment, China University of Geosciences Beijing, Beijing 100083, China.
J Hazard Mater. 2023 Jun 5;451:131055. doi: 10.1016/j.jhazmat.2023.131055. Epub 2023 Feb 22.
The widely applied aromatic nitration in modern industry leads to toxic p-nitrophenol (PNP) in environment. Exploring its efficient degradation routes is of great interests. In this study, a novel four-step sequential modification procedure was developed to increase the specific surface area, functional group, hydrophilicity, and conductivity of carbon felt (CF). The implementation of the modified CF promoted reductive PNP biodegradation, attaining 95.2 ± 0.8% of removal efficiency with less accumulation of highly toxic organic intermediates (e.g., p-aminophenol), compared to carrier-free and CF-packed biosystems. The constructed anaerobic-aerobic process with modified CF in 219-d continuous operation achieved further removal of carbon and nitrogen containing intermediates and partial mineralization of PNP. The modified CF promoted the secretion of extracellular polymeric substances (EPS) and cytochrome c (Cyt c), which were essential components to facilitate direct interspecies electron transfer (DIET). Synergistic relationship was deduced that glucose was converted into volatile fatty acids by fermenters (e.g., Longilinea and Syntrophobacter), which donated electrons to the PNP degraders (e.g., Bacteroidetes_vadinHA17) through DIET channels (CF, Cyt c, EPS) to complete PNP removal. This study proposes a novel strategy using engineered conductive material to enhance the DIET process for efficient and sustainable PNP bioremediation.
在现代工业中广泛应用的芳香族硝化作用会导致环境中产生有毒的对硝基苯酚（PNP）。探索其有效的降解途径具有重要意义。在本研究中，开发了一种新颖的四步连续修饰程序，以提高碳纤维毡（CF）的比表面积、官能团、亲水性和导电性。改性 CF 的实施促进了还原型 PNP 的生物降解，与无载体和 CF 填充生物系统相比，去除效率达到 95.2±0.8%，同时很少积累高毒性有机中间产物（例如对氨基酚）。在 219 天的连续运行中，用改性 CF 构建的厌氧-好氧工艺进一步去除了含碳和氮的中间产物，并部分矿化了 PNP。改性 CF 促进了细胞外聚合物物质（EPS）和细胞色素 c（Cyt c）的分泌，这是促进直接种间电子转移（DIET）的必要组成部分。推断出协同关系，即发酵菌（例如长双歧杆菌和互营杆菌）将葡萄糖转化为挥发性脂肪酸，然后通过 DIET 通道（CF、Cyt c、EPS）将电子捐赠给 PNP 降解菌（例如拟杆菌门_vadinHA17），从而完成 PNP 的去除。本研究提出了一种使用工程导电材料增强 DIET 过程的新策略，以实现高效和可持续的 PNP 生物修复。
