Environmental Research最新文献

A gut bacterial supplement for Asian honey bee (Apis cerana) enhances host tolerance to nitenpyram: Insight from microbiota–gut–brain axis

IF 7.7 2区环境科学与生态学 Q1 ENVIRONMENTAL SCIENCES

Environmental Research

Pub Date : 2025-03-05 DOI: 10.1016/j.envres.2025.121306

Chonghui Zhao , Yehua Peng , Muhammad Fahad Raza , Wenbo Wang , Yi Zhang , Yanping Chen , Richou Han , Jun Guo , Shaokang Huang , Wenfeng Li

The widespread use of neonicotinoid pesticides has severely impacted honey bees, driving population declines. Gut microbiota are increasingly recognized for their role in mitigating pesticide toxicity. This study evaluated the ability of Gilliamella sp. G0441, a core microbiome member of the Asian honey bee (Apis cerana), to confer resistance to the toxicity of a neonicotinoid nitenpyram. Newly emerged Asian honey bees were first colonized with gut microbiota in the source colony, then divided into four treatments: SS (fed sucrose solution throughout), SN (fed sucrose solution, then exposed to nitenpyram), GS (fed Gilliamella, then sucrose solution), and GN (fed Gilliamella, then exposed to nitenpyram), and their responses—mortality, food consumption, body weight, and sucrose sensitivity—were assessed. The protective effects of Gilliamella administration on the host were further validated using a microbiota-free bee model. Gilliamella supplementation significantly mitigated nitenpyram-induced appetite suppression, weight loss, impaired learning, and gut microbiota disruption. Mechanistic analyses revealed that nitenpyram disrupted brain metabolism via the intestinal MAPK pathway, reducing ascorbate and aldarate metabolism. Prophylactic Gilliamella treatment reversed these effects, restored metabolic balance, and modulated esterase E4 expression, enhancing pesticide resistance. This study underscores Gilliamella's vital role in honey bee resilience to neonicotinoids, offering insights into the microbiota-gut-brain axis (MGBA) as a pathway for enhancing pesticide tolerance and ecological health.

{"title":"A gut bacterial supplement for Asian honey bee (Apis cerana) enhances host tolerance to nitenpyram: Insight from microbiota–gut–brain axis","authors":"Chonghui Zhao , Yehua Peng , Muhammad Fahad Raza , Wenbo Wang , Yi Zhang , Yanping Chen , Richou Han , Jun Guo , Shaokang Huang , Wenfeng Li","doi":"10.1016/j.envres.2025.121306","DOIUrl":"10.1016/j.envres.2025.121306","url":null,"abstract":"<div><div>The widespread use of neonicotinoid pesticides has severely impacted honey bees, driving population declines. Gut microbiota are increasingly recognized for their role in mitigating pesticide toxicity. This study evaluated the ability of Gilliamella sp. G0441, a core microbiome member of the Asian honey bee (Apis cerana), to confer resistance to the toxicity of a neonicotinoid nitenpyram. Newly emerged Asian honey bees were first colonized with gut microbiota in the source colony, then divided into four treatments: SS (fed sucrose solution throughout), SN (fed sucrose solution, then exposed to nitenpyram), GS (fed Gilliamella, then sucrose solution), and GN (fed Gilliamella, then exposed to nitenpyram), and their responses—mortality, food consumption, body weight, and sucrose sensitivity—were assessed. The protective effects of Gilliamella administration on the host were further validated using a microbiota-free bee model. Gilliamella supplementation significantly mitigated nitenpyram-induced appetite suppression, weight loss, impaired learning, and gut microbiota disruption. Mechanistic analyses revealed that nitenpyram disrupted brain metabolism via the intestinal MAPK pathway, reducing ascorbate and aldarate metabolism. Prophylactic Gilliamella treatment reversed these effects, restored metabolic balance, and modulated esterase E4 expression, enhancing pesticide resistance. This study underscores Gilliamella's vital role in honey bee resilience to neonicotinoids, offering insights into the microbiota-gut-brain axis (MGBA) as a pathway for enhancing pesticide tolerance and ecological health.</div></div>","PeriodicalId":312,"journal":{"name":"Environmental Research","volume":"274 ","pages":"Article 121306"},"PeriodicalIF":7.7,"publicationDate":"2025-03-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143562836","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Changes in rainfall impact the release of metal elements in the litter of a subtropical mixed forest.

IF 7.7 2区环境科学与生态学 Q1 ENVIRONMENTAL SCIENCES

Environmental Research

Pub Date : 2025-03-04 DOI: 10.1016/j.envres.2025.121293

Jian Feng, Yunchao Zhou, Yunxing Bai, Manyi Fan, Yaoxiong Wang, Fenghua Tang, Jirong Feng

The release of metal elements from litter decomposition in forest ecosystems is crucial for material cycling and ecosystem health, but the impact of future variations in rainfall due to climatic fluctuations on this release is unknown. This study conducted an outdoor rainfall variability simulation and an in situ litter decomposition experiment in a subtropical location, with a focus on pure Pinus massoniana (PM) and four PM mixed stands (PM+Bretschneidera sinensis, PM+Cercidiphyllum japonicum, PM+Taxus wallichiana, and PM+Nageia nagi). We studied the release of metal elements from litter after one year of decomposition under different rainfall conditions (30% increase, natural, and 30% decrease) and calculated the mixing effect on the litter. The results showed that K, Mg, Mn, Cu and Zn were released and Na, Ca and Fe were enriched after one year of litter decomposition. Increased rainfall promoted K, Na, Mg, Mn, and Zn release, reduced Fe and Cu release, enhanced the synergistic effect of Na and Mn release, and exacerbated the antagonistic effect of Cu. Decreased rainfall reduced the synergistic effect of mixed litter on the release of Na, Ca, Mg, and Fe, while enhancing the synergistic effect of Mn and Zn. The lower degree of metal element release from single PM litter resulted in the enrichment of metal elements in the litter of apoplasts. The effect of rainfall variability on metal element release was more significant compared to tree species characteristics. Overall, decreased rainfall inhibited metal element release and slowed down element cycling; increased rainfall promoted Na and Mn release and accelerated Cu enrichment. It is noteworthy that mixed litter effectively mitigated the effects of rainfall changes on metal element release by regulating elemental cycling. The findings of this study add to a better understanding of nutrient dynamics in forest ecosystems and offer techniques and insights for addressing future climate change.

{"title":"Changes in rainfall impact the release of metal elements in the litter of a subtropical mixed forest.","authors":"Jian Feng, Yunchao Zhou, Yunxing Bai, Manyi Fan, Yaoxiong Wang, Fenghua Tang, Jirong Feng","doi":"10.1016/j.envres.2025.121293","DOIUrl":"https://doi.org/10.1016/j.envres.2025.121293","url":null,"abstract":"The release of metal elements from litter decomposition in forest ecosystems is crucial for material cycling and ecosystem health, but the impact of future variations in rainfall due to climatic fluctuations on this release is unknown. This study conducted an outdoor rainfall variability simulation and an in situ litter decomposition experiment in a subtropical location, with a focus on pure Pinus massoniana (PM) and four PM mixed stands (PM+Bretschneidera sinensis, PM+Cercidiphyllum japonicum, PM+Taxus wallichiana, and PM+Nageia nagi). We studied the release of metal elements from litter after one year of decomposition under different rainfall conditions (30% increase, natural, and 30% decrease) and calculated the mixing effect on the litter. The results showed that K, Mg, Mn, Cu and Zn were released and Na, Ca and Fe were enriched after one year of litter decomposition. Increased rainfall promoted K, Na, Mg, Mn, and Zn release, reduced Fe and Cu release, enhanced the synergistic effect of Na and Mn release, and exacerbated the antagonistic effect of Cu. Decreased rainfall reduced the synergistic effect of mixed litter on the release of Na, Ca, Mg, and Fe, while enhancing the synergistic effect of Mn and Zn. The lower degree of metal element release from single PM litter resulted in the enrichment of metal elements in the litter of apoplasts. The effect of rainfall variability on metal element release was more significant compared to tree species characteristics. Overall, decreased rainfall inhibited metal element release and slowed down element cycling; increased rainfall promoted Na and Mn release and accelerated Cu enrichment. It is noteworthy that mixed litter effectively mitigated the effects of rainfall changes on metal element release by regulating elemental cycling. The findings of this study add to a better understanding of nutrient dynamics in forest ecosystems and offer techniques and insights for addressing future climate change.","PeriodicalId":312,"journal":{"name":"Environmental Research","volume":" ","pages":"121293"},"PeriodicalIF":7.7,"publicationDate":"2025-03-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143571745","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

New insights into Peniophora crassitunicata and its co-inoculation with commercial microbial inoculant accelerating lignocellulose degradation and compost maturation during orchard wastes composting.

IF 7.7 2区环境科学与生态学 Q1 ENVIRONMENTAL SCIENCES

Environmental Research

Pub Date : 2025-03-04 DOI: 10.1016/j.envres.2025.121298

Juan Zhan, Qinghua Liu, Junwen Chen, Xueyong Pang

Lignocellulosic composting has been widely promoted in the utilization of agricultural wastes, while few focus on orchard lignocellulosic wastes in the fruit industry. Peniophora is a laccase hyper-producer highly efficient in lignin degradation, yet its application in lignocellulosic composting has not been investigated. Here, an aerobic composting experiment was conducted to investigate the effects of inoculation with Peniophora crassitunicata and a commercial microbial inoculant (mainly Bacillus and Aspergillus) on grape (Vitis Vinifera L.) orchard lignocellulosic wastes degradation and the underlying mechanisms. The inoculation with P. crassitunicata, both individually (H) and in combination with the commercial microbial inoculant (HS), enhanced lignocellulose degradation efficiency. Notably, the co-inoculation exhibited higher lignocellulose degradation ratios and higher lignocellulosic enzyme activities compared to other treatments. The compost piles with co-inoculation experienced a more rapid temperature rise, a longer duration (15 days) of high temperatures, lower pH, and lower electrical conductivity (EC). Firmicutes (e.g. Bacillus, Paenibacillus) and Ascomycota (e.g. Aspergillus) along with Bacteroidota, Actinobacteriota, and Basidiomycota (e.g. Peniophora) dominated the microbial community in compost; carbohydrate metabolism dominated microbial metabolic pathways at the thermophilic phase, highlighting an active microbial community. As compost processed, highly mature and non-toxic compost products were finally obtained for the co-inoculation, with a pH of 7.87, C/N ratio of 13.5, NH₄⁺-N/NO₃^‾-N ratio of 0.21-0.41, EC of 0.90 mS cm^-1, and germination index of 149 %. The co-inoculation of P. crassitunicata with the commercial microbial inoculant effectively accelerated lignocellulose degradation and compost maturation, producing a friendly and non-toxic organic fertilizer for agricultural applications and thereby providing a new strategy for orchard wastes management and agricultural applications.

{"title":"New insights into Peniophora crassitunicata and its co-inoculation with commercial microbial inoculant accelerating lignocellulose degradation and compost maturation during orchard wastes composting.","authors":"Juan Zhan, Qinghua Liu, Junwen Chen, Xueyong Pang","doi":"10.1016/j.envres.2025.121298","DOIUrl":"https://doi.org/10.1016/j.envres.2025.121298","url":null,"abstract":"Lignocellulosic composting has been widely promoted in the utilization of agricultural wastes, while few focus on orchard lignocellulosic wastes in the fruit industry. Peniophora is a laccase hyper-producer highly efficient in lignin degradation, yet its application in lignocellulosic composting has not been investigated. Here, an aerobic composting experiment was conducted to investigate the effects of inoculation with Peniophora crassitunicata and a commercial microbial inoculant (mainly Bacillus and Aspergillus) on grape (Vitis Vinifera L.) orchard lignocellulosic wastes degradation and the underlying mechanisms. The inoculation with P. crassitunicata, both individually (H) and in combination with the commercial microbial inoculant (HS), enhanced lignocellulose degradation efficiency. Notably, the co-inoculation exhibited higher lignocellulose degradation ratios and higher lignocellulosic enzyme activities compared to other treatments. The compost piles with co-inoculation experienced a more rapid temperature rise, a longer duration (15 days) of high temperatures, lower pH, and lower electrical conductivity (EC). Firmicutes (e.g. Bacillus, Paenibacillus) and Ascomycota (e.g. Aspergillus) along with Bacteroidota, Actinobacteriota, and Basidiomycota (e.g. Peniophora) dominated the microbial community in compost; carbohydrate metabolism dominated microbial metabolic pathways at the thermophilic phase, highlighting an active microbial community. As compost processed, highly mature and non-toxic compost products were finally obtained for the co-inoculation, with a pH of 7.87, C/N ratio of 13.5, NH4+-N/NO3‾-N ratio of 0.21-0.41, EC of 0.90 mS cm-1, and germination index of 149 %. The co-inoculation of P. crassitunicata with the commercial microbial inoculant effectively accelerated lignocellulose degradation and compost maturation, producing a friendly and non-toxic organic fertilizer for agricultural applications and thereby providing a new strategy for orchard wastes management and agricultural applications.","PeriodicalId":312,"journal":{"name":"Environmental Research","volume":" ","pages":"121298"},"PeriodicalIF":7.7,"publicationDate":"2025-03-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143571813","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Preparation of porous sustainable adsorbent and its adsorption behavior for Pb².

IF 7.7 2区环境科学与生态学 Q1 ENVIRONMENTAL SCIENCES

Environmental Research

Pub Date : 2025-03-04 DOI: 10.1016/j.envres.2025.121289

Yuhang Guo, Xiao Chen, Xiaoping Feng, Mingyang Zhao, Yating Pan, Kai Zhang, Jinhui Li

Using granulated blast furnace slag as raw material, chitosan and NaCl as modifier, chitosan modified granulated blast furnace slag based porous geopolymer (PCG) was prepared under the activation conditions of NaOH and sodium silicate. It was used to wrap different types of lightweight aggregates to obtain PCG-lightweight aggregate shell-core structure (PCG-L). PCG-L was used for the adsorption of Pb²⁺. Firstly, the influencing factors on the adsorption performance of the main component materials (PCG, lightweight aggregates) of PCG-L were studied. Then, the static adsorption properties and sustainable adsorption properties of Pb²⁺ by different shell-core structures were investigated. The relationship between the water absorption characteristics of the paste and the aggregate and the adsorption characteristics of PCG-L towards Pb²⁺ was established. The adsorption kinetics, adsorption isotherms and adsorption thermodynamics were analyzed. Finally, the adsorption mechanism of PCG-L was discussed by Zeta analyzer, FT-IR, EDS, XPS and MIP. The results indicate that as chitosan (0-2wt%) and NaCl (0-60wt%) increase, the saturated adsorption capacity of PCG for Pb²⁺ rises (98.57-159.93mg/g). The Pb²⁺ adsorption capacity of lightweight aggregate (0.34-1.21g/dm³) increases with its water absorption (0.2-15.0%). Under the premise that the water absorption rate of aggregate is greater than that of PCG, the higher the water absorption rate of the two, the stronger the adsorption capacity of the matching PCG-L, the maximum adsorption capacity of A2N30-H is 5.12g/dm³ and it can still maintain a high removal rate after 40 cycles of adsorption. PCG-L adsorption via ion exchange, electrostatic attraction, surface complexation, and pore fixation.

{"title":"Preparation of porous sustainable adsorbent and its adsorption behavior for Pb2.","authors":"Yuhang Guo, Xiao Chen, Xiaoping Feng, Mingyang Zhao, Yating Pan, Kai Zhang, Jinhui Li","doi":"10.1016/j.envres.2025.121289","DOIUrl":"https://doi.org/10.1016/j.envres.2025.121289","url":null,"abstract":"Using granulated blast furnace slag as raw material, chitosan and NaCl as modifier, chitosan modified granulated blast furnace slag based porous geopolymer (PCG) was prepared under the activation conditions of NaOH and sodium silicate. It was used to wrap different types of lightweight aggregates to obtain PCG-lightweight aggregate shell-core structure (PCG-L). PCG-L was used for the adsorption of Pb2+. Firstly, the influencing factors on the adsorption performance of the main component materials (PCG, lightweight aggregates) of PCG-L were studied. Then, the static adsorption properties and sustainable adsorption properties of Pb2+ by different shell-core structures were investigated. The relationship between the water absorption characteristics of the paste and the aggregate and the adsorption characteristics of PCG-L towards Pb2+ was established. The adsorption kinetics, adsorption isotherms and adsorption thermodynamics were analyzed. Finally, the adsorption mechanism of PCG-L was discussed by Zeta analyzer, FT-IR, EDS, XPS and MIP. The results indicate that as chitosan (0-2wt%) and NaCl (0-60wt%) increase, the saturated adsorption capacity of PCG for Pb2+ rises (98.57-159.93mg/g). The Pb2+ adsorption capacity of lightweight aggregate (0.34-1.21g/dm3) increases with its water absorption (0.2-15.0%). Under the premise that the water absorption rate of aggregate is greater than that of PCG, the higher the water absorption rate of the two, the stronger the adsorption capacity of the matching PCG-L, the maximum adsorption capacity of A2N30-H is 5.12g/dm3 and it can still maintain a high removal rate after 40 cycles of adsorption. PCG-L adsorption via ion exchange, electrostatic attraction, surface complexation, and pore fixation.","PeriodicalId":312,"journal":{"name":"Environmental Research","volume":" ","pages":"121289"},"PeriodicalIF":7.7,"publicationDate":"2025-03-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143571856","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Metatranscriptomics sheds light on electron transfer in anammox bacteria enhanced by the redox mediator neutral red

IF 7.7 2区环境科学与生态学 Q1 ENVIRONMENTAL SCIENCES

Environmental Research

Pub Date : 2025-03-04 DOI: 10.1016/j.envres.2025.121288

Xingcheng Zhao , Fangxu Jia , Bo Wang , ZhiFeng Hu , Baohong Han , Ning Mei , Feirui Jia , Yawen Liu , Hong Yao

Enhancing the activity of key enzymes has been recognized as an effective strategy to improve anammox performance. Neutral red (NR), a potent redox-active electron carrier, has been shown to boost various enzyme activities and microbial reaction rates. However, its potential to enhance anammox performance remains underexplored. This study aimed to investigate the effects of different NR concentrations on anammox nitrogen removal efficiency and gene transcription levels. The results revealed that anammox activity increased with NR doses in the lower concentration range (0.05–0.3 g L⁻¹). The optimal dosage at 0.1 g L⁻¹ significantly increased specific anammox activity (SAA) by 16.73 ± 2.68% (p ≤ 0.001), compared to the control without NR addition. Moreover, the total EPS concentration increased by 16.87 ± 1.20% (p ≤ 0.01). Conversely, NR concentrations exceeding the optimal range inhibited anammox activity. Metatranscriptomic analysis showed that appropriate NR supplementation upregulated the expression of cofactor modules related to electron transfer and functional genes (hdh and hzsB) involved in anammox nitrogen removal, thereby enhancing overall performance. Moreover, the mild oxidative stress induced by low NR doses was mitigated through the upregulation of antioxidant genes. In contrast, excessive NR (0.5–1.0 g L⁻¹) led to an accumulation of reactive oxygen species (ROS) that overwhelmed the antioxidant defense system, resulting in impaired electron transfer and reduced metabolic activity. Specifically, when the NR concentration was increased to 1.0 g L⁻¹, SAA decreased significantly by 26.45 ± 2.55% (p ≤ 0.001). These findings indicate that appropriately controlled NR supplementation can improve anammox activity, providing a promising strategy for rapid start-up and improved nitrogen removal in practical anammox systems.

{"title":"Metatranscriptomics sheds light on electron transfer in anammox bacteria enhanced by the redox mediator neutral red","authors":"Xingcheng Zhao , Fangxu Jia , Bo Wang , ZhiFeng Hu , Baohong Han , Ning Mei , Feirui Jia , Yawen Liu , Hong Yao","doi":"10.1016/j.envres.2025.121288","DOIUrl":"10.1016/j.envres.2025.121288","url":null,"abstract":"<div><div>Enhancing the activity of key enzymes has been recognized as an effective strategy to improve anammox performance. Neutral red (NR), a potent redox-active electron carrier, has been shown to boost various enzyme activities and microbial reaction rates. However, its potential to enhance anammox performance remains underexplored. This study aimed to investigate the effects of different NR concentrations on anammox nitrogen removal efficiency and gene transcription levels. The results revealed that anammox activity increased with NR doses in the lower concentration range (0.05–0.3 g L−1). The optimal dosage at 0.1 g L−1 significantly increased specific anammox activity (SAA) by 16.73 ± 2.68% (p ≤ 0.001), compared to the control without NR addition. Moreover, the total EPS concentration increased by 16.87 ± 1.20% (p ≤ 0.01). Conversely, NR concentrations exceeding the optimal range inhibited anammox activity. Metatranscriptomic analysis showed that appropriate NR supplementation upregulated the expression of cofactor modules related to electron transfer and functional genes (hdh and hzsB) involved in anammox nitrogen removal, thereby enhancing overall performance. Moreover, the mild oxidative stress induced by low NR doses was mitigated through the upregulation of antioxidant genes. In contrast, excessive NR (0.5–1.0 g L−1) led to an accumulation of reactive oxygen species (ROS) that overwhelmed the antioxidant defense system, resulting in impaired electron transfer and reduced metabolic activity. Specifically, when the NR concentration was increased to 1.0 g L−1, SAA decreased significantly by 26.45 ± 2.55% (p ≤ 0.001). These findings indicate that appropriately controlled NR supplementation can improve anammox activity, providing a promising strategy for rapid start-up and improved nitrogen removal in practical anammox systems.</div></div>","PeriodicalId":312,"journal":{"name":"Environmental Research","volume":"274 ","pages":"Article 121288"},"PeriodicalIF":7.7,"publicationDate":"2025-03-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143549787","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Metabolic and ecological responses of denitrifying consortia to different carbon source strategies under fluctuating C/N conditions

IF 7.7 2区环境科学与生态学 Q1 ENVIRONMENTAL SCIENCES

Environmental Research

Pub Date : 2025-03-04 DOI: 10.1016/j.envres.2025.121292

Rui-Zhe Sun , Yuan Pan , Jun Wang , Tong Gao , Han-Qing Yu , Jin Wang

Frequent fluctuations in the carbon-to-nitrogen (C/N) ratio of urban wastewater influent can undermine denitrification performance, posing challenges for stable nitrogen removal. Although supplying additional carbon sources is a recognized strategy to mitigate these issues, the underlying microbial interactions and metabolic reconfigurations triggered by changing C/N ratios remain incompletely understood. Here, we employed methanol, glycerol, sodium acetate, and glucose in long-term denitrification reactors and integrated denitrification kinetics, 16S rRNA gene amplicon sequencing, metagenomic binning, and metabolic modeling to elucidate how these systems respond to a declining C/N ratio. Our results show that lower C/N ratios diminished denitrification efficiency in all treatments, with each carbon source eliciting distinct shifts in microbial assemblages. Fluctuations in the C/N ratio determine the extent of directional selection of microbial communities based on carbon source metabolism and induce significant changes in non-dominant microorganisms. Throughout the process, the synthesis potential of PHA is closely linked to the system's ability to withstand fluctuations. Notably, metabolic modeling indicated that heightened tricarboxylic acid (TCA) cycle activity in the methanol- and glucose-fed communities was associated with suboptimal nitrogen removal. These findings offer novel insights into the metabolic and ecological mechanisms governing carbon source–driven denitrification under fluctuating C/N conditions, providing a valuable framework for optimizing nitrogen removal in urban wastewater treatment systems.

{"title":"Metabolic and ecological responses of denitrifying consortia to different carbon source strategies under fluctuating C/N conditions","authors":"Rui-Zhe Sun , Yuan Pan , Jun Wang , Tong Gao , Han-Qing Yu , Jin Wang","doi":"10.1016/j.envres.2025.121292","DOIUrl":"10.1016/j.envres.2025.121292","url":null,"abstract":"<div><div>Frequent fluctuations in the carbon-to-nitrogen (C/N) ratio of urban wastewater influent can undermine denitrification performance, posing challenges for stable nitrogen removal. Although supplying additional carbon sources is a recognized strategy to mitigate these issues, the underlying microbial interactions and metabolic reconfigurations triggered by changing C/N ratios remain incompletely understood. Here, we employed methanol, glycerol, sodium acetate, and glucose in long-term denitrification reactors and integrated denitrification kinetics, 16S rRNA gene amplicon sequencing, metagenomic binning, and metabolic modeling to elucidate how these systems respond to a declining C/N ratio. Our results show that lower C/N ratios diminished denitrification efficiency in all treatments, with each carbon source eliciting distinct shifts in microbial assemblages. Fluctuations in the C/N ratio determine the extent of directional selection of microbial communities based on carbon source metabolism and induce significant changes in non-dominant microorganisms. Throughout the process, the synthesis potential of PHA is closely linked to the system's ability to withstand fluctuations. Notably, metabolic modeling indicated that heightened tricarboxylic acid (TCA) cycle activity in the methanol- and glucose-fed communities was associated with suboptimal nitrogen removal. These findings offer novel insights into the metabolic and ecological mechanisms governing carbon source–driven denitrification under fluctuating C/N conditions, providing a valuable framework for optimizing nitrogen removal in urban wastewater treatment systems.</div></div>","PeriodicalId":312,"journal":{"name":"Environmental Research","volume":"274 ","pages":"Article 121292"},"PeriodicalIF":7.7,"publicationDate":"2025-03-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143562813","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Fe3+ addition as a promising strategy to enhance the pollutant removal performance and mitigate the membrane fouling of a laboratory-scale membrane bioreactor treating sulfamethoxazole wastewater

IF 7.7 2区环境科学与生态学 Q1 ENVIRONMENTAL SCIENCES

Environmental Research

Pub Date : 2025-03-04 DOI: 10.1016/j.envres.2025.121284

Lanhe Zhang , Rumeng Bai , Jian Zhang , Zicheng Chen , Jingbo Guo

Membrane bioreactor (MBR) is a water treatment process combining membrane technologies with activated sludge, which is beneficial to the removal of antibiotics. However, with the extension of the operation cycle, its efficiency in treating antibiotic wastewater decreases and the membrane fouling intensifies. As the presence of Fe³⁺ could improve pollutants removal, microbial activity and sludge properties, it was anticipated that the addition of Fe³⁺ in MBR might promote the removal of antibiotics and reduce membrane fouling. The effects of Fe³⁺ concentration on the removal of sulfamethoxazole (SMX) and membrane fouling were investigated in this work. The results revealed that the removal efficiencies of COD, TN, and SMX was 98%, 86%, and 70%, respectively, when 40 mg/L Fe³⁺ was introduced into MBR with the influent SMX concentration of 1 mg/L. This performance was superior to that observed in the absence of Fe³⁺, which was 93%, 74%, and 53% for COD, TN, and SMX removal, respectively. Correspondingly, the membrane fouling rate decreased from 2.52 kPa/d to 1.03 kPa/d, demonstrating that Fe³⁺ could mitigate membrane fouling. The exploration into membrane fouling mechanism demonstrated that the flocculation of activated sludge was enhanced and the protein (PN) content in the cake layer was significantly reduced. Concurrently, the repulsive energy barrier (XDLVO) between foulants and membrane surface was markedly increased. The study identified four SMX degradation pathways, i.e., N-S bond breaking, C-S bond breaking, N-O bond breaking, and benzene ring deamination. The toxicity levels of the degradation intermediates were determined to span from harmless to toxic as compared with SMX itself. This study offers new insights into the enhanced elimination of SMX through the MBR-Fe process and elucidates the mechanisms involved in mitigating membrane fouling, highlighting the potential of this process in degrading antibiotic wastewater.

{"title":"Fe3+ addition as a promising strategy to enhance the pollutant removal performance and mitigate the membrane fouling of a laboratory-scale membrane bioreactor treating sulfamethoxazole wastewater","authors":"Lanhe Zhang , Rumeng Bai , Jian Zhang , Zicheng Chen , Jingbo Guo","doi":"10.1016/j.envres.2025.121284","DOIUrl":"10.1016/j.envres.2025.121284","url":null,"abstract":"<div><div>Membrane bioreactor (MBR) is a water treatment process combining membrane technologies with activated sludge, which is beneficial to the removal of antibiotics. However, with the extension of the operation cycle, its efficiency in treating antibiotic wastewater decreases and the membrane fouling intensifies. As the presence of Fe3+ could improve pollutants removal, microbial activity and sludge properties, it was anticipated that the addition of Fe3+ in MBR might promote the removal of antibiotics and reduce membrane fouling. The effects of Fe3+ concentration on the removal of sulfamethoxazole (SMX) and membrane fouling were investigated in this work. The results revealed that the removal efficiencies of COD, TN, and SMX was 98%, 86%, and 70%, respectively, when 40 mg/L Fe3+ was introduced into MBR with the influent SMX concentration of 1 mg/L. This performance was superior to that observed in the absence of Fe3+, which was 93%, 74%, and 53% for COD, TN, and SMX removal, respectively. Correspondingly, the membrane fouling rate decreased from 2.52 kPa/d to 1.03 kPa/d, demonstrating that Fe3+ could mitigate membrane fouling. The exploration into membrane fouling mechanism demonstrated that the flocculation of activated sludge was enhanced and the protein (PN) content in the cake layer was significantly reduced. Concurrently, the repulsive energy barrier (XDLVO) between foulants and membrane surface was markedly increased. The study identified four SMX degradation pathways, i.e., N-S bond breaking, C-S bond breaking, N-O bond breaking, and benzene ring deamination. The toxicity levels of the degradation intermediates were determined to span from harmless to toxic as compared with SMX itself. This study offers new insights into the enhanced elimination of SMX through the MBR-Fe process and elucidates the mechanisms involved in mitigating membrane fouling, highlighting the potential of this process in degrading antibiotic wastewater.</div></div>","PeriodicalId":312,"journal":{"name":"Environmental Research","volume":"274 ","pages":"Article 121284"},"PeriodicalIF":7.7,"publicationDate":"2025-03-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143562814","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

The chronic effects of polyethylene terephthalate and biodegradable polyhydroxybutyrate microplastics on Daphnia magna

IF 7.7 2区环境科学与生态学 Q1 ENVIRONMENTAL SCIENCES

Environmental Research

Pub Date : 2025-03-04 DOI: 10.1016/j.envres.2025.121281

Teresa Serra , Fabiola Vilaseca , Jordi Colomer

The inappropriate disposal of plastic materials and their slow decomposition into microplastics (MP) pollutes aquatic ecosystems, leading to toxic effects on organisms. MP can have different shapes and be made from different polymeric materials; being carbon-based polymers the common ones. The toxicity associated with such MP has led to the need to search for alternative polymers with faster degradation times. Biodegradable polymers such as polyhydroxybutyrate (PHB) are promising substitutes for synthetic polymers. In this work, the environmental impact of PHB was determined and compared to that of polyethylene terephthalate (PET). For this purpose, the model organism Daphnia magna was used in a 26-day experiment. The toxic effects of MPs was assessed by analysing the survival, the swimming velocity and the filtration rate of Daphnia magna. After 21 days of exposure, PET in the form of fibers or fragments caused the most toxicity, resulting in a 20% decrease in swimming velocity and a 20% of Daphnia magna survival. However, after 21 days, PHB resulted in 80% survival, which is comparable to control experiments, and Daphnia magna showed mobility that was comparable to that seen for control experiments.

Therefore, with the presence of food PHB microplastic particles had no negative effects on Daphnia magna. Considering these results, PHB might be a promising material as a substitute of conventional polymers.

{"title":"The chronic effects of polyethylene terephthalate and biodegradable polyhydroxybutyrate microplastics on Daphnia magna","authors":"Teresa Serra , Fabiola Vilaseca , Jordi Colomer","doi":"10.1016/j.envres.2025.121281","DOIUrl":"10.1016/j.envres.2025.121281","url":null,"abstract":"<div><div>The inappropriate disposal of plastic materials and their slow decomposition into microplastics (MP) pollutes aquatic ecosystems, leading to toxic effects on organisms. MP can have different shapes and be made from different polymeric materials; being carbon-based polymers the common ones. The toxicity associated with such MP has led to the need to search for alternative polymers with faster degradation times. Biodegradable polymers such as polyhydroxybutyrate (PHB) are promising substitutes for synthetic polymers. In this work, the environmental impact of PHB was determined and compared to that of polyethylene terephthalate (PET). For this purpose, the model organism Daphnia magna was used in a 26-day experiment. The toxic effects of MPs was assessed by analysing the survival, the swimming velocity and the filtration rate of Daphnia magna. After 21 days of exposure, PET in the form of fibers or fragments caused the most toxicity, resulting in a 20% decrease in swimming velocity and a 20% of Daphnia magna survival. However, after 21 days, PHB resulted in 80% survival, which is comparable to control experiments, and Daphnia magna showed mobility that was comparable to that seen for control experiments.</div><div>Therefore, with the presence of food PHB microplastic particles had no negative effects on Daphnia magna. Considering these results, PHB might be a promising material as a substitute of conventional polymers.</div></div>","PeriodicalId":312,"journal":{"name":"Environmental Research","volume":"274 ","pages":"Article 121281"},"PeriodicalIF":7.7,"publicationDate":"2025-03-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143562966","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Construction of MoS₂/g-C₃N₄ S-scheme heterojunction promotes plasma-photocatalytic degradation of methyl p-hydroxybenzoate: Electron transfer and adsorption reduction mechanisms.

IF 7.7 2区环境科学与生态学 Q1 ENVIRONMENTAL SCIENCES

Environmental Research

Pub Date : 2025-03-04 DOI: 10.1016/j.envres.2025.121285

Yu Duan, Bingyan Dong, Xiao Gu, Peixiang Wang, Junwen He, Xueyi Zhi, Zhendong Li

A novel method of S-scheme heterojunction photocatalyst assisted with plasma was proposed to degrade the methyl p-hydroxybenzoate (MeP) in wastewater. The two-dimensional MoS₂/g-C₃N₄ composite was prepared by the thermal polycondensation method. The sheet-like morphologies and S-scheme heterogeneous structure were validated by XRD, XPS, EDS, FTIR, and TEM in the MoS₂/g-C₃N₄ composite. The addition of MoS₂/g-C₃N₄ increased the MeP degradation from 74.85% to 89.85% and the TOC removal rate from 25.16% to 40.12%. The MeP solution reduced the toxicity after treating the plasma/MoS₂/g-C₃N₄ system. Quenching experiments and electron paramagnetic resonance (EPR) spectra showed that the UV light generated by the discharge is utilized by the catalyst, which increases the yield of O₂^-· and ¹O₂, enhancing the degradation efficiency of MeP. The absorption spectral range and electron transfer ability are improved by the interaction between MoS₂ and g-C₃N₄. The proposed charge transfer mechanism is driven by the S-scheme heterojunction built-in electric field (IEF), thereby reducing the recombination of photogenerated electron-hole pairs. The production of free radicals is increased by the adsorption-reduction reaction on the surface of MoS₂ and g-C₃N₄. In addition, the catalytic material has good photocatalytic performance after recycling. MoS₂/g-C₃N₄ combined with plasma exhibits excellent photocatalytic performance and has a wide range of application prospects.

{"title":"Construction of MoS2/g-C3N4 S-scheme heterojunction promotes plasma-photocatalytic degradation of methyl p-hydroxybenzoate: Electron transfer and adsorption reduction mechanisms.","authors":"Yu Duan, Bingyan Dong, Xiao Gu, Peixiang Wang, Junwen He, Xueyi Zhi, Zhendong Li","doi":"10.1016/j.envres.2025.121285","DOIUrl":"https://doi.org/10.1016/j.envres.2025.121285","url":null,"abstract":"A novel method of S-scheme heterojunction photocatalyst assisted with plasma was proposed to degrade the methyl p-hydroxybenzoate (MeP) in wastewater. The two-dimensional MoS2/g-C3N4 composite was prepared by the thermal polycondensation method. The sheet-like morphologies and S-scheme heterogeneous structure were validated by XRD, XPS, EDS, FTIR, and TEM in the MoS2/g-C3N4 composite. The addition of MoS2/g-C3N4 increased the MeP degradation from 74.85% to 89.85% and the TOC removal rate from 25.16% to 40.12%. The MeP solution reduced the toxicity after treating the plasma/MoS2/g-C3N4 system. Quenching experiments and electron paramagnetic resonance (EPR) spectra showed that the UV light generated by the discharge is utilized by the catalyst, which increases the yield of O2-· and 1O2, enhancing the degradation efficiency of MeP. The absorption spectral range and electron transfer ability are improved by the interaction between MoS2 and g-C3N4. The proposed charge transfer mechanism is driven by the S-scheme heterojunction built-in electric field (IEF), thereby reducing the recombination of photogenerated electron-hole pairs. The production of free radicals is increased by the adsorption-reduction reaction on the surface of MoS2 and g-C3N4. In addition, the catalytic material has good photocatalytic performance after recycling. MoS2/g-C3N4 combined with plasma exhibits excellent photocatalytic performance and has a wide range of application prospects.","PeriodicalId":312,"journal":{"name":"Environmental Research","volume":" ","pages":"121285"},"PeriodicalIF":7.7,"publicationDate":"2025-03-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143571748","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Synergistic microalgae-duckweed systems for enhanced aquaculture wastewater treatment, biomass recovery, and CO2 sequestration: A novel approach for sustainable resource recovery

IF 7.7 2区环境科学与生态学 Q1 ENVIRONMENTAL SCIENCES

Environmental Research

Pub Date : 2025-03-04 DOI: 10.1016/j.envres.2025.121271

Yingjie Song , Zhangli Hu , Xuewei Yang , Yuxing An , Yinglin Lu

Current aquaculture practices generate nutrient-rich effluents that cause significant environmental pollution. This study presents a novel synergistic microalgae-duckweed system integrating Chlorella sp. and Spirodela polyrhiza for sustainable wastewater treatment, biomass valorization, and carbon sequestration. Over a 15-day treatment period, the system achieved unprecedented removal efficiencies: 91.25% for NO₃⁻-N, 98.90% for NH₄⁺-N, 100% for total phosphorus, and a 95% reduction in chemical oxygen demand (COD). Concurrently, the system produced 6.67 g/L of microalgal biomass and 90 g/m² of duckweed biomass significantly higher than those of standalone systems, which showed enhanced protein and lipid contents suitable for bioenergy or feed applications. The dual system sequestered CO₂ at a remarkable rate of 1.65 g/L/day, exceeding standalone treatments. Microbial community analysis revealed enriched functional diversity, promoting optimized nutrient cycling and organic matter degradation. Although the system was tested at a lab scale, it demonstrates promising scalability due to its efficient nutrient removal and biomass production, as well as the robustness of the combined microalgae-duckweed treatment approach. This integrated approach not only addresses water pollution but also advances the circular economy by converting aquaculture waste into high-value biomass and mitigating carbon emissions. These findings position the synergistic microalgae-duckweed system as a scalable and eco-friendly solution for sustainable aquaculture management and environmental conservation.

{"title":"Synergistic microalgae-duckweed systems for enhanced aquaculture wastewater treatment, biomass recovery, and CO2 sequestration: A novel approach for sustainable resource recovery","authors":"Yingjie Song , Zhangli Hu , Xuewei Yang , Yuxing An , Yinglin Lu","doi":"10.1016/j.envres.2025.121271","DOIUrl":"10.1016/j.envres.2025.121271","url":null,"abstract":"<div><div>Current aquaculture practices generate nutrient-rich effluents that cause significant environmental pollution. This study presents a novel synergistic microalgae-duckweed system integrating Chlorella sp. and Spirodela polyrhiza for sustainable wastewater treatment, biomass valorization, and carbon sequestration. Over a 15-day treatment period, the system achieved unprecedented removal efficiencies: 91.25% for NO3−-N, 98.90% for NH4+-N, 100% for total phosphorus, and a 95% reduction in chemical oxygen demand (COD). Concurrently, the system produced 6.67 g/L of microalgal biomass and 90 g/m2 of duckweed biomass significantly higher than those of standalone systems, which showed enhanced protein and lipid contents suitable for bioenergy or feed applications. The dual system sequestered CO2 at a remarkable rate of 1.65 g/L/day, exceeding standalone treatments. Microbial community analysis revealed enriched functional diversity, promoting optimized nutrient cycling and organic matter degradation. Although the system was tested at a lab scale, it demonstrates promising scalability due to its efficient nutrient removal and biomass production, as well as the robustness of the combined microalgae-duckweed treatment approach. This integrated approach not only addresses water pollution but also advances the circular economy by converting aquaculture waste into high-value biomass and mitigating carbon emissions. These findings position the synergistic microalgae-duckweed system as a scalable and eco-friendly solution for sustainable aquaculture management and environmental conservation.</div></div>","PeriodicalId":312,"journal":{"name":"Environmental Research","volume":"274 ","pages":"Article 121271"},"PeriodicalIF":7.7,"publicationDate":"2025-03-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143562801","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0