JOURNAL OF CONTAMINANT HYDROLOGY
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2025
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IF 4.4
Ting Liu,Mengting Xiao,Rongshan Du,Meng Li,Xinyi Li,Ying Xi,Yuanfei Lv,Honglin Liu,Yingping Huang,Tao Xu
Periphytic biofilms (PBs) and dissolved organic matter (DOM) are key factors affecting the migration of Cd at the “water-sediment” interface. However, the specific effects of PBs and protein-like components of DOM on Cd migration within the “water-biofilm-sediment” system remain poorly understood. This study simulates the dissolution and re-immobilization of Cd at the “water-biofilm-sediment” interface in the water-level fluctuation zone (WLFZ) of the Three Gorges Reservoir (TGR), aiming to clarify the role of PBs in Cd stability. The results indicate that the concentration of dissolved Cd increased by 0.96-fold (R 2 = 0.992) with each doubling of L-tryptophan (L-Trp) concentration, as the functional groups of L-Trp ( COOH and NH) formed complexes with Fe-Mn oxide-bound Cd in the sediment. In the presence of PBs and at an L-Trp concentration of 150 mg·L −1 , PBs utilized L-Trp, resulting in a 16.7 % reduction in dissolved organic carbon (DOC) ( p < 0.05) and an increase in protein content. Additionally, PBs contributed to a 35.12 % reduction in the peak concentration of dissolved Cd, thereby stabilizing the final Cd levels. Cd enrichment within PBs, facilitated by functional groups such as >C C<, OH, >C O, and C O , led to a significant increase in Cd content (0.43 mg·kg −1 , p < 0.05). These findings suggest that L-Trp degradation and Cd enrichment by PBs act synergistically to promote the re-immobilization of dissolved Cd. This study offers a novel perspective on Cd migration in WLFZs and provides insights that may be applicable to other aquatic environments where PBs are present.
研究领域:
环境科学
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水文学
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DOI
PubMed
高影响因子
Environmental Science-Nano
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2017
·Vol. 4
·期 8
·1682-1691
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IF 6.047
Jun Tang,Ningyuan Zhu,Yan Zhu,Philip Kerr,Yonghong Wu
The roles of different extracellular polymeric substance (EPS) fractions in microbial communities, such as periphytic biofilms, are unclear. In this study, three EPS fractions extracted from a periphytic biofilm were employed to investigate their ability to affect Fe2O3 nanoparticle (IONP) toxicity. The addition of IONPs promoted the production of EPS and reactive oxygen species. The bound EPS protected the microbial cells in the periphytic biofilm from oxidative damage caused by IONPs. Different EPS fractions had different roles in affecting IONPs via different mechanisms, specifically, the soluble EPS increased the hydrodynamic diameter of IONPs and promoted IONP aggregation, the flocculation efficiency of the tightly bound EPS increased during exposure to IONPs, and the loosely bound EPS presented high biosorption of IONPs. The binding of IONPs with abundant functional groups was the main combination mode between different EPS fractions and IONPs. The beneficial changes in composition, structure and functional groups of EPS during exposure to IONPs in turn facilitate the elimination of their toxicity. This study contributes to a better understanding of the resistance mechanism of the periphytic biofilm to IONP exposure and the roles of EPS fractions in defending against nanotoxicity.
研究领域:
微生物学
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环境毒理学
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生物膜研究
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纳米材料生物学效应
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生态毒理学
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DOI
高影响因子
CHEMOSPHERE
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2022
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IF 8.943
Jun Hong,Xuhui Huang,Zhikai Wang,Xingzhang Luo,Suzhen Huang,Zheng Zheng
With the wide application of plastic products, microplastic pollution has become a major environmental issue of global concern. Microplastics in aquatic environments can interact with organic pollutants, causing a combined effect on submerged macrophytes . This study investigated the response mechanisms of the submerged plant Myriophyllum verticillatum and epiphytic biofilm to the antibiotic enrofloxacin, microplastics, and their combined exposure in a high nitrogen and phosphorus environment. The results indicated that Myriophyllum verticillatum was not sensitive to enrofloxacin of 1 mg L −1 , while 10 and 50 mg L −1 enrofloxacin inhibited the uptake of nitrogen and phosphorus by the plants, as well as triggered oxidative stress in the plant leaves, causing irreversible damage to the plant cells. In addition, enrofloxacin altered the structure of the leaf epiphytic biofilm community. Interestingly, 1, 5, and 20 mg L −1 microplastics had no significant effect on the plant, while they facilitated the aggregation of microorganisms , increasing the abundance of the leaf epiphyte biofilm. The combination of enrofloxacin and microplastics induced a synergistic effect on Myriophyllum verticillatum . Specifically, the rate of nitrogen and phosphorus uptake by the plant was reduced, the content of photosynthetic pigments decreased, and antioxidant enzyme activity was further increased. In addition, the diversity of the leaf epiphytic biofilm community was similar to the single enrofloxacin exposure. These results demonstrated the differences between single and combined exposures and provided a new theoretical basis to evaluate the harmful effects of enrofloxacin and microplastics on submerged macrophytes.
研究领域:
环境科学
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生态毒理学
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水生植物学
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微生物学
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DOI
PubMed
高影响因子
Environmental Science-Nano
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2019
·Vol. 7
·期 2
·665-675
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IF 7.704
Jun Hou,Tengfei Li,Lingzhan Miao,Guoxiang You,Yi Xu,Songqi Liu
The widespread application of TiO2 NPs will lead to their increasing release into the aquatic environment and thus affects the ecosystem function of aquatic life. As a microbial community, responses of periphytic biofilm to toxicity of TiO2 NPs are largely unknown, in particular with respect to dynamic shifts of community structure and microbial functions of periphytic biofilms. Therefore, this study investigated the relationship between microbial functions and community composition of periphytic biofilms after chronic exposure (21 days) to 50 μg L−1 and 500 μg L−1 TiO2 NPs. The increase of DOC in surface water was inhibited during the first 11 days (49.55%) by 500 μg L−1 TiO2 NPs and then recovered. Distinct responses were observed between community structure and microbial functions of biofilms after exposure to TiO2 NPs. Specifically, both 50 μg L−1 and 500 μg L−1 TiO2 NPs promoted the growth of microalgae (78.85–134.86%) and altered the bacterial community composition at day 7, and these trends lasted at day 21. In terms of the microbial functions determined using Biolog™ ECO microplates, biofilms maintained their total carbon metabolic activities under the stress of 50 μg L−1 TiO2 NPs. However, the carbon metabolic activities were significantly inhibited (24.63%) by the exposure to 500 μg L−1 TiO2 NPs at day 7 and then recovered to the control level at day 21. Although inhibition still existed in the metabolic activity for carbohydrate (17.00%) after long-term exposure, periphytic biofilms exhibited resistance to TiO2 NPs and continuous decrease in nanotoxicity was observed.
研究领域:
环境微生物学
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水生生态学
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纳米毒理学
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DOI
高影响因子
JOURNAL OF HAZARDOUS MATERIALS
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2021
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IF 10.588
Shujie Cai,Haotian Wang,Jun Tang,Xiufeng Tang,Peng Guan,Jiuyu Li,Yuji Jiang,Yonghong Wu,Renkou Xu
The increasing use of nanoparticles (NPs) has raised concerns about their potential environmental risks. Many researches on NPs focused on the toxicity mechanism to microorganisms , but neglect the toxicity effects in relation to nutritional conditions. Here, we evaluated the interactive effects of zinc oxide (ZnO) NPs and phosphorus (P) levels on the bacterial community and functioning of periphytic biofilms. Results showed that long-term exposure to ZnO NPs significantly reduced alkaline phosphatase activity (APA) of periphytic biofilms just in P-limited conditions. Co-occurrence network analysis indicated that ZnO NPs exposure reduced network complexity between bacterial taxa in P-limited conditions, while the opposite trend was observed in P-replete conditions. Correlation analysis and random forest modeling suggested that excessive Zn 2+ released and high reactive oxygen species (ROS) production might be mainly responsible for the inhibition of APA induced by ZnO NPs under P-limited conditions, while adjustment of bacterial diversity and improvement of keystone taxa cooperation were the main mechanisms in maintaining APA when subjected to weak toxicity of ZnO NPs in P-replete conditions. Taken together, our results provide insights into the biological feedback mechanism involved in ZnO NPs exposure on the ecological function of periphytic biofilms in different P nutritional conditions.
研究领域:
环境科学
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微生物学
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生态毒理学
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产品关联
DOI
PubMed
高影响因子
JOURNAL OF HAZARDOUS MATERIALS
·
2025
·
IF 11.3
Zuqiang Cao,Juan Chen,Chao Wang,Peifang Wang,Han Gao,Bingbing Feng,Bo Zhang,Rong Wang,Ge Cui
Periphytic biofilms are ubiquitous and drive biogeochemical nutrient cycling in paddy ecosystems. However, the mechanisms of multi-kingdom microbial interactions regulating nitrogen (N) cycling in the biofilms remain unexplored. This study conducted a microcosm experiment to investigate the effects of imidacloprid (IMI), a widely used neonicotinoid pesticide, on N cycling in periphytic biofilms. Throughout the 30-day experiment, 0.02–0.12 mg of N was lost from the water-biofilm microcosm systems, increasing with higher IMI exposure concentrations. Metatranscriptomic sequencing demonstrated 84.3 %–92.2 % downregulation of nitrification genes and 33.9 %–143 % upregulation of denitrification genes in the biofilms. These alterations in gene expression were regulated by microbial competition and cooperation within ecological clusters associated with the biofilm potential nitrification and denitrification activities, respectively. Correlation between the relative abundance of microorganisms in these clusters and gene abundance revealed multi-kingdom nitrifying and denitrifying communities, including Nitrosopumilus (Archaea) and Nitrospira (Bacteria) for nitrification, and Enterococcus (Bacteria) and Aspergillus (Fungi) for denitrification. Partial least squares path modeling indicated that the biofilm-mediated N loss was driven by promoted denitrification (total effect = −0.83) rather than suppressed nitrification (total effect = 0.52). Our findings highlight multi-kingdom microbial interactions regulating N cycling in periphytic biofilms and neonicotinoid pesticide risks.
研究领域:
环境微生物学
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生态毒理学
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生物地球化学
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水生生态学
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农药科学
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宏转录组学
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DOI
PubMed
高影响因子
危险品化学品经营许可证（带存储）