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1.
Environ Res ; 238(Pt 1): 117106, 2023 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-37699472

RESUMO

Wastewater treatment plants (WWTPs) effluent often contains a significant amount of residual organic pollutants and nutrients, causing disturbance to the coastal effluent receiving areas (ERA). Microbial communities in coastal ERA sediments may benefit from the coexistence of organic pollutants and nutrients, promoting the emergence of versatile taxa that are capable of eliminating these substances simultaneously. However, the identification and exploration of versatile taxa in natural environments under anthropogenic disturbances remain largely uncharted territory. In this study, we specifically focused on the versatile taxa coupled by the degradation of aromatic compounds (ACs) and denitrification, using Hangzhou Bay in China as our study area. We explored how WWTPs effluent disturbance would affect the versatile taxa, and particularly examined the role of disturbance intensity in shaping their composition. Intriguingly, we found that versatile taxa were mainly derived from denitrifiers like Pseudomonas, suggesting the fulfilled potential of denitrifiers regarding ACs degradation. We also discovered that moderate disturbance stimulated the diversity of versatile taxa, resulting in strengthened functional redundancy. Through correlation network analysis, we further demonstrated that moderate disturbance enhanced the community-level cooperation. Thus, moderate disturbance serves as a catalyst for versatile taxa to maintain community function, making them more resilient to effluent disturbances. Additionally, we identified COD and NO3--N concentrations as significant environmental factors influencing the versatile taxa. Overall, our findings reveal the role of effluent disturbances in the promotion of versatile taxa, and highlight moderate disturbance can foster more robust versatile taxa that are better equipped to handle effluent disturbances.


Assuntos
Poluentes Ambientais , Microbiota , Desnitrificação , Efeitos Antropogênicos , China
2.
J Craniofac Surg ; 33(8): e837-e840, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35882350

RESUMO

BACKGROUND: Meningiomas are usually dura-based primary nonmalignant neoplasms of the central nervous system. It is extremely rare that a meningioma is located at the convexity of the brain, but shows no dura attachment and causes osteolysis of the skull. CASE PRESENTATION: A 57-year-old woman presented with an incidentally discovered scalp lump on the head. Neurological deficits were not found. Radiological examination revealed a localized osteolytic lesion in the right parietal bone, which was initially diagnosed as a bone tumor and was surgically resected. At surgery, a tumor mass was found located at the brain convexity without dura attachment. It was tightly attached to the brain parenchyma and had no distinct boundary from the brain. The mass was rather small, but resulted in significant osteolysis of the skull and destruction of the dura. Simpson grade I resection of the tumor was performed. Histological and immunohistochemical results indicated a meningothelial meningioma. CONCLUSIONS: Both preoperative and intraoperative diagnoses are difficult for this case. Knowledge of this case is crucial for clinicians to be aware of this entity because it can be easily confused with bone tumors. Further research on the relationship between meningioma and bone metabolism is required to investigate the mechanism of osteolysis.


Assuntos
Neoplasias Ósseas , Neoplasias Meníngeas , Meningioma , Osteólise , Feminino , Humanos , Pessoa de Meia-Idade , Meningioma/diagnóstico por imagem , Meningioma/cirurgia , Neoplasias Meníngeas/diagnóstico por imagem , Neoplasias Meníngeas/cirurgia , Osteólise/diagnóstico por imagem , Osteólise/cirurgia , Imageamento por Ressonância Magnética , Dura-Máter , Neoplasias Ósseas/patologia
3.
Microb Ecol ; 79(2): 342-356, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31428833

RESUMO

Current technologies could identify the abundance and functions of specific microbes, and evaluate their individual effects on microbial ecology. However, these microbes interact with each other, as well as environmental factors, in the form of complex network. Determination of their combined ecological influences remains a challenge. In this study, we developed a tripartite microbial-environment network (TMEN) analysis method that integrates microbial abundance, metabolic function, and environmental data as a tripartite network to investigate the combined ecological effects of microbes. Applying TMEN to analyzing the microbial-environment community structure in the sediments of Hangzhou Bay, one of the most seriously polluted coastal areas in China, we found that microbes were well-organized into 4 bacterial communities and 9 archaeal communities. The total organic carbon, sulfate, chemical oxygen demand, salinity, and nitrogen-related indexes were detected as crucial environmental factors in the microbial-environmental network. With close interactions with these environmental factors, Nitrospirales and Methanimicrococcu were identified as hub microbes with connection advantage. Our TMEN method could close the gap between lack of efficient statistical and computational approaches and the booming of large-scale microbial genomic and environmental data. Based on TMEN, we discovered a potential microbial ecological mechanism that crucial species with significant influence on the microbial community ecology would possess one or two of the community advantages for enhancing their ecological status and essentiality, including abundance advantage and connection advantage.


Assuntos
Archaea/fisiologia , Fenômenos Fisiológicos Bacterianos , Baías/microbiologia , Sedimentos Geológicos/microbiologia , Consórcios Microbianos , Técnicas Microbiológicas/métodos , China
4.
Sensors (Basel) ; 20(11)2020 Jun 11.
Artigo em Inglês | MEDLINE | ID: mdl-32545229

RESUMO

This study investigates the effect of process parameters on neurosurgical bone grinding performance using a miniature surgical diamond wheel. Bone grinding is an important procedure in the expanded endonasal approach for removing the cranial bone and access to the skull base tumor via nasal corridor. Heat and force are generated during the grinding process, which may cause thermal and mechanical damage to the adjacent tissues. This study investigates the effect of grinding process parameters (including the depth of cut, feed rate, and spindle speed) on the bone grinding performance using temperature and force measurement sensors in order to optimize the grinding process. An orthogonal experimental design with a standard orthogonal array, L9 (33), is selected with each parameter in three levels. The experimental results have been statistically analyzed using the range and variance analysis methods in order to determine the importance order of the process parameters. The results indicate that the effect of the cutting depth on the grinding temperature and normal force is the largest, while the effect of the spindle speed on the tangential force is the largest. A high spindle speed would make the temperature rise to a certain extent; however, it significantly reduces the grinding force. At a certain spindle speed, a lower depth of cut and feed rate help to reduce the grinding temperature and force.


Assuntos
Osso e Ossos , Fenômenos Mecânicos , Temperatura Alta , Humanos , Temperatura , Dispositivos Eletrônicos Vestíveis
5.
J Environ Sci (China) ; 81: 156-167, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-30975318

RESUMO

The coastal area of the East China Sea has experienced rapid urbanization and industrialization in China since 1980s, resulting in severe pollution of its environments. Antibiotic resistance genes (ARGs) are regarded as a kind of emerging pollutant with potential high risk. The sediment samples were collected from Hangzhou Bay (HB), Xiangshan Bay (XB), and Taizhou Bay (TB) to investigate the spatial occurrence and distribution of 27 ARGs and class I integron-integrase gene (intI1) in the coastal area of the East China Sea. The PCR results showed the frequent presence of 11 ARGs and intI1 in the sediments of the three bays. The qPCR results further showed that sulfonamide resistance was the most prevalent ARG type and antibiotic target replacement and protection were the most important resistance mechanisms in the sediments. Regarding the subtype of ARGs, sulI, tetW, and dfrA13 were the most abundant ARGs, in which sulI was higher in TB (based on both the absolute and relative abundances) and dfrA13 was higher in HB (based on the relative abundances). The network analysis revealed that intI1 had significant correlations with tetC, sulI, sulII, and blaPSE-1. Oil was the key connected factor, which had positive connections with sulI, sulII, and blaPSE-1. In addition, the joint effect of heavy metals and nutrients & organic pollutants might be crucial for the fate of ARGs in the coastal sediments.


Assuntos
Resistência Microbiana a Medicamentos/genética , Monitoramento Ambiental , Genes Bacterianos , Poluição da Água/análise , China , Sedimentos Geológicos/química , Poluição da Água/estatística & dados numéricos
6.
Environ Sci Technol ; 52(1): 248-257, 2018 01 02.
Artigo em Inglês | MEDLINE | ID: mdl-29182858

RESUMO

Cell-associated ARGs in wastewater treatment plants (WWTPs) has been concerned, however, cell-free ARGs in WWTPs was rarely studied. In this study, the abundances of four representative ARGs, sulII, tetC, blaPSE-1, and ermB, in a large municipal WWTP were investigated in both cell-associated and cell-free fractions. Cell-associated ARGs was the dominant ARGs fraction in the raw wastewater. After biological treatment, sludge settling, membrane filtration, and disinfection, cell-associated ARGs were substantially reduced, though the ratios of ARG/16S rRNA gene were increased with disinfection. Cell-free ARGs persisted in the WWTP with a removal of 0.36 log to 2.68 logs, which was much lower than the removal of cell-associated ARGs (3.21 logs to 4.14 logs). Therefore, the abundance ratio of cell-free ARGs to cell-associated ARGs increased from 0.04-1.59% to 2.00-1895.08% along the treatment processes. After 25-day-storage, cell-free ARGs in both biological effluent and disinfection effluent increased by 0.14 log to 1.99 logs and 0.12 log to 1.77 logs respectively, reflecting the persistence and low decay rate of cell-free ARGs in the discharge water. Therefore, cell-free ARGs might be a kind of important but previously neglected pollutant from WWTPs, which added potential risks to the effluent receiving environments.


Assuntos
Ácidos Nucleicos Livres , Águas Residuárias , Antibacterianos , Resistência Microbiana a Medicamentos , Genes Bacterianos , RNA Ribossômico 16S , Eliminação de Resíduos Líquidos
7.
Appl Microbiol Biotechnol ; 100(13): 6035-45, 2016 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-26960319

RESUMO

The community structure of ammonia-oxidizing microorganisms is sensitive to various environmental factors, including pollutions. In this study, real-time PCR and 454 pyrosequencing were adopted to investigate the population and diversity of ammonia-oxidizing archaea (AOA) and bacteria (AOB) temporally and spatially in the sediments of an industrial effluent receiving area in the Qiantang River's estuary, Hangzhou Bay. The abundances of AOA and AOB amoA genes fluctuated in 10(5)-10(7) gene copies per gram of sediment; the ratio of AOA amoA/AOB amoA ranged in 0.39-5.52. The AOA amoA/archaeal 16S rRNA, AOB amoA/bacterial 16S rRNA, and AOA amoA/AOB amoA were found to positively correlate with NH4 (+)-N concentration of the seawater. Nitrosopumilus cluster and Nitrosomonas-like cluster were the dominant AOA and AOB, respectively. The community structures of both AOA and AOB in the sediments exhibited significant seasonal differences rather than spatial changes in the effluent receiving area. The phylogenetic distribution of AOB in this area was consistent with the wastewater treatment plants (WWTPs) discharging the effluent but differed from the Qiantang River and other estuaries, which might be an outcome of long-term effluent discharge.


Assuntos
Amônia/metabolismo , Archaea/isolamento & purificação , Bactérias/isolamento & purificação , Baías/microbiologia , Biodiversidade , Archaea/classificação , Archaea/genética , Archaea/metabolismo , Bactérias/classificação , Bactérias/genética , Bactérias/metabolismo , Baías/análise , China , Sedimentos Geológicos/química , Sedimentos Geológicos/microbiologia , Oxirredução , Filogenia , Poluição Química da Água/análise
8.
J Environ Sci (China) ; 44: 57-68, 2016 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-27266302

RESUMO

Anthropogenic activities usually contaminate water environments, and have led to the eutrophication of many estuaries and shifts in microbial communities. In this study, the temporal and spatial changes of the microbial community in an industrial effluent receiving area in Hangzhou Bay were investigated by 454 pyrosequencing. The bacterial community showed higher richness and biodiversity than the archaeal community in all sediments. Proteobacteria dominated in the bacterial communities of all the samples; Marine_Group_I and Methanomicrobia were the two dominant archaeal classes in the effluent receiving area. PCoA and AMOVA revealed strong seasonal but minor spatial changes in both bacterial and archaeal communities in the sediments. The seasonal changes of the bacterial community were less significant than those of the archaeal community, which mainly consisted of fluctuations in abundance of a large proportion of longstanding species rather than the appearance and disappearance of major archaeal species. Temperature was found to positively correlate with the dominant bacteria, Betaproteobacteria, and negatively correlate with the dominant archaea, Marine_Group_I; and might be the primary driving force for the seasonal variation of the microbial community.


Assuntos
Baías/microbiologia , Monitoramento Ambiental , Resíduos Industriais , Águas Residuárias/microbiologia , Microbiologia da Água , Archaea , Bactérias , Biodiversidade , China , Euryarchaeota , Eutrofização , Sedimentos Geológicos/microbiologia , Proteobactérias
9.
Appl Microbiol Biotechnol ; 99(22): 9825-33, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26219499

RESUMO

Estuarine sediment-seawater microcosms were established to evaluate the influence of salinity on the population, transcriptional activity, and diversity of ammonia-oxidizing archaea (AOA) and bacteria (AOB). AOA was found to show the most abundant and the highest transcriptional activity under moderate salinity; on the other hand, AOB abundance was not sensitive to salinity variation but showed the highest transcriptional activity in the low-salinity microcosms. AOA exhibited more advantages than AOB on growth and ammonia-oxidizing activity under moderate- and high-salinity environments. The highest richness and diversity of active AOA were found under salinity of 15 psu. All the active AOA detected under the salinities studied were clustered into Nitrosopumilus maritimus linage, with the composition shifted from N. maritimus C12 cluster, N. maritimus like 1.1 cluster, N. maritimus SCM1 cluster, and N. maritimus like 1.2 cluster to N. maritimus C12 and N. maritimus A10 clusters when salinity was increased from 5 to 30 psu.


Assuntos
Amônia/metabolismo , Archaea/classificação , Bactérias/classificação , Biodiversidade , Sedimentos Geológicos/microbiologia , Salinidade , Transcrição Gênica , Archaea/genética , Bactérias/genética , Estuários , Oxirredução
10.
Appl Microbiol Biotechnol ; 99(15): 6481-91, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-25797330

RESUMO

Ammonia was observed as a potential significant factor to manipulate the abundance and activity of ammonia-oxidizing microorganisms (AOMs) in water environments. For the first time, this study confirmed this phenomenon by laboratory cultivation. In a series of estuarine sediment-coastal water microcosms, we investigated the AOM's phylogenetic composition and activity change in response to ammonia concentration. Increase of ammonia concentration promoted bacterial amoA gene abundance in a linear pattern. The ratio of transcribed ammonia-oxidizing bacteria (AOB) amoA gene/ammonia-oxidizing archaea (AOA) amoA gene increased from 0.1 to 43 as NH4 (+)-N increased from less than 0.1 to 12 mg L(-1), and AOA amoA transcription was undetected under 20 mg NH4 (+)-N L(-1). The incubation of stable isotope probing (SIP) microcosms revealed a faster (13)C-NaHCO3 incorporation rate of AOA amoA gene under 0.1 mg NH4 (+)-N L(-1) and a sole (13)C-NaHCO3 utilization of the AOB amoA gene under 20 mg NH4 (+)-N L(-1). Our results indicate that ammonia concentration manipulates the structure of AOM. AOA prefers to live and perform higher amoA transcription activity than AOB in ammonia-limited water environments, and AOB tends to take the first contributor place in ammonia-rich ones.


Assuntos
Amônia/metabolismo , Archaea/crescimento & desenvolvimento , Bactérias/crescimento & desenvolvimento , Biota , Sedimentos Geológicos/microbiologia , Água do Mar/química , Archaea/metabolismo , Bactérias/metabolismo , DNA Arqueal/química , DNA Arqueal/genética , DNA Bacteriano/química , DNA Bacteriano/genética , Marcação por Isótopo , Modelos Teóricos , Dados de Sequência Molecular , Oxirredução , Oxirredutases/genética , Filogenia , Análise de Sequência de DNA
11.
Appl Microbiol Biotechnol ; 99(10): 4495-507, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25586577

RESUMO

Under the increasing pressure of human activities, Hangzhou Bay has become one of the most seriously polluted waters along China's coast. Considering the excessive inorganic nitrogen detected in the bay, in this study, the impact of an effluent from a coastal industrial park on ammonia-oxidizing microorganisms (AOMs) of the receiving area was interpreted for the first time by molecular technologies. Revealed by real-time PCR, the ratio of archaeal amoA/bacterial amoA ranged from 5.68 × 10(-6) to 4.79 × 10(-5) in the activated sludge from two wastewater treatment plants (WWTPs) and 0.54-3.44 in the sediments from the effluent receiving coastal area. Analyzed by clone and pyrosequencing libraries, genus Nitrosomonas was the predominant ammonia-oxidizing bacteria (AOB), but no ammonia-oxidizing archaea (AOA) was abundant enough for sequencing in the activated sludge from the WWTPs; genus Nitrosomonas and Nitrosopumilus were the dominant AOB and AOA, respectively, in the coastal sediments. The different abundance of AOA but similar structure of AOB between the WWTPs and nearby coastal area probably indicated an anthropogenic impact on the microbial ecology in Hangzhou Bay.


Assuntos
Amônia/metabolismo , Archaea/metabolismo , Bactérias/metabolismo , Sedimentos Geológicos/microbiologia , Esgotos/microbiologia , Archaea/classificação , Archaea/genética , Archaea/isolamento & purificação , Bactérias/classificação , Bactérias/genética , Bactérias/isolamento & purificação , Biodiversidade , China , Resíduos Industriais/análise , Dados de Sequência Molecular , Filogenia , Águas Residuárias/química , Purificação da Água/instrumentação
12.
J Environ Sci (China) ; 29: 45-50, 2015 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-25766012

RESUMO

In this study, ultraviolet (UV) and vacuum ultraviolet (VUV) photolysis were investigated for the pre-treatment and post-treatment of coking wastewater. First, 6-fold diluted raw coking wastewater was irradiated by UV and VUV. It was found that 15.9%-35.4% total organic carbon (TOC) was removed after 24 hr irradiation. The irradiated effluent could be degraded by the acclimated activated sludge. Even though the VUV photolysis removed more chemical oxygen demand (COD) than UV, the UV-irradiated effluent demonstrated better biodegradability. After 4 hr UV irradiation, the biological oxygen demand BOD5/COD ratio of irradiated coking wastewater increased from 0.163 to 0.224, and its toxicity decreased to the greatest extent. Second, the biologically treated coking wastewater was irradiated by UV and VUV. Both of them were able to remove 37%-47% TOC within 8 hr irradiation. Compared to UV, VUV photolysis could significantly improve the transparency of the bio-treated effluent. VUV also reduced 7% more ammonia nitrogen (NH4+-N), 17% more nitrite nitrogen (NO2--N), and 18% more total nitrogen (TN) than UV, producing 35% less nitrite nitrogen (NO3--N) as a result. In conclusion, UV irradiation was better in improving the biodegradability of coking wastewater, while VUV was more effective at photolyzing the residual organic compounds and inorganic N-species in the bio-treated effluent.


Assuntos
Coque/análise , Fotólise , Raios Ultravioleta , Vácuo , Águas Residuárias/química , Poluentes Químicos da Água/química , Reatores Biológicos , Resíduos Industriais , Eliminação de Resíduos Líquidos/instrumentação , Eliminação de Resíduos Líquidos/métodos
13.
Appl Microbiol Biotechnol ; 98(2): 863-73, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23546424

RESUMO

Bioaugmentation with degrading bacteria is an effective method to improve the treatment of refractory industrial wastewater; nevertheless there were controversial opinions about the fate of inoculated bacteria and microbial community dynamics. In this study, two lab-scale sequencing batch reactors filled with modified zeolite were used to treat a coking wastewater with pyridine and quinoline shock load, and a bacterial consortium containing three degrading strains was added in one reactor for bioaugmentation. During 120-day operation, the bioaugmented reactor removed over 99 % pyridine, 99 % quinoline, 85 % TOC, 65 % COD, and 95 % NO3⁻--N with higher resistance to the shock load than the non-bioaugmented reactor. Based on the terminal restriction fragment length polymorphism of 16S rDNA, bacterial community diversity increased in the bioaugmented reactor. Principal component analysis revealed that, to cope with the shock load, the indigenous bacterial community recovered to the initial structure by acclimatizing itself constantly to the inhospitable environment; but bioaugmentation accelerated the shift of whole bacterial community, resulting in a far different structure from the initial one. Canonical correspondence analysis indicated that the environmental parameters of pyridine, quinoline, TOC, and NO3⁻--N had close negative correlations with bioaugmentation; and NH3--N and COD were the main parameters to impact on the bacterial community changes and treatment efficiency.


Assuntos
Reatores Biológicos/microbiologia , Biota , Águas Residuárias/química , Águas Residuárias/microbiologia , Poluentes da Água/metabolismo , Zeolitas , Bactérias/classificação , Bactérias/genética , Análise da Demanda Biológica de Oxigênio , Biotransformação , Carbono/análise , Impressões Digitais de DNA , Nitrogênio/análise , Polimorfismo de Fragmento de Restrição , Piridinas/metabolismo , Quinolonas/metabolismo , RNA Ribossômico 16S/genética
14.
Environ Int ; 190: 108887, 2024 Jul 14.
Artigo em Inglês | MEDLINE | ID: mdl-39024826

RESUMO

Bacterial community is strongly associated with activated sludge performance, but there still remains a knowledge gap regarding the rare bacterial community assembly and their influence on the system performance in industrial wastewater treatment plants (IWWTPs). Here, we investigated bacterial communities in 11 full-scale IWWTPs with similar process designs, aiming to uncover ecological processes and functional traits regulating abundant and rare communities. Our findings indicated that abundant bacterial community assembly was governed by stochastic processes; thereby, abundant taxa are generally present in wastewater treatment compartments across different industrial types. On the contrary, rare bacterial taxa were primarily driven by deterministic processes (homogeneous selection 61.9%-79.7%), thus they only exited in specific IWWTPs compartments and wastewater types. The co-occurrence networks analysis showed that the majority of keystone taxa were rare bacterial taxa, with rare taxa contributing more to network stability. Furthermore, rare bacteria rather than abundant bacteria in the oxic compartment contributed more to the degradation of xenobiotics compounds, and they were main potential drivers of pollutant removal. This study demonstrated the irreplaceable roles of rare bacterial taxa in maintaining system performance of IWWTPs, and called for environmental engineers and microbial ecologists to increase their attention on rare biosphere.

15.
Environ Sci Ecotechnol ; 20: 100370, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38292137

RESUMO

Domestic and industrial wastewater treatment plants (WWTPs) are facing formidable challenges in effectively eliminating emerging pollutants and conventional nutrients. In microbiome engineering, two approaches have been developed: a top-down method focusing on domesticating seed microbiomes into engineered ones, and a bottom-up strategy that synthesizes engineered microbiomes from microbial isolates. However, these approaches face substantial hurdles that limit their real-world applicability in wastewater treatment engineering. Addressing this gap, we propose the creation of a Global WWTP Microbiome-based Integrative Information Platform, inspired by the untapped microbiome and engineering data from WWTPs and advancements in artificial intelligence (AI). This open platform integrates microbiome and engineering information globally and utilizes AI-driven tools for identifying seed microbiomes for new plants, providing technical upgrades for existing facilities, and deploying microbiomes for accidental pollution remediation. Beyond its practical applications, this platform has significant scientific and social value, supporting multidisciplinary research, documenting microbial evolution, advancing Wastewater-Based Epidemiology, and enhancing global resource sharing. Overall, the platform is expected to enhance WWTPs' performance in pollution control, safeguarding a harmonious and healthy future for human society and the natural environment.

16.
Water Res ; 257: 121697, 2024 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-38728787

RESUMO

Quorum sensing (QS)-based manipulations emerge as a promising solution for biofilm reactors to overcome challenges from inefficient biofilm formation and lengthy start-ups. However, the ecological mechanisms underlying how QS regulates microbial behaviors and community assembly remain elusive. Herein, by introducing different levels of N-acyl-homoserine lactones, we manipulated the strength of QS during the start-up of moving bed biofilm reactors and compared the dynamics of bacterial communities. We found that enhanced QS elevated the fitness of fast-growing bacteria with high ribosomal RNA operon (rrn) copy numbers in their genomes in both the sludge and biofilm communities. This led to notably increased extracellular substance production, as evidenced by strong positive correlations between community-level rrn copy numbers and extracellular proteins and polysaccharides (Pearson's r = 0.529-0.830, P < 0.001). Network analyses demonstrated that enhanced QS significantly promoted the ecological interactions among taxa, particularly cooperative interactions. Bacterial taxa with higher network degrees were more strongly correlated with extracellular substances, suggesting their crucial roles as public goods in regulating bacterial interactions and shaping network structures. However, the assembly of more cooperative communities in QS-enhanced reactors came at the cost of decreased network stability and modularity. Null model and dissimilarity-overlap curve analysis revealed that enhanced QS strengthened stochastic processes in community assembly and rendered the universal population dynamics more convergent. Additionally, these shaping effects were consistent for both the sludge and biofilm communities, underpinning the planktonic-to-biofilm transition. This work highlights that QS manipulations efficiently drive community assembly and confer specialized functional traits to communities by recruiting taxa with specific life strategies and regulating interspecific interactions. These ecological insights deepen our understanding of the rules governing microbial societies and provide guidance for managing engineering ecosystems.


Assuntos
Biofilmes , Reatores Biológicos , Percepção de Quorum , Esgotos , Esgotos/microbiologia , Acil-Butirolactonas/metabolismo , Bactérias/genética , Bactérias/metabolismo
17.
Sci Total Environ ; 914: 169982, 2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-38215846

RESUMO

The ecological impact of microplastics (MPs) in coastal environments has been widely studied. However, the influence of small microplastics in the actual environment is often overlooked due to measurement challenges. In this study, Hangzhou Bay (HZB), China, was selected as our study area. High-throughput metagenomic sequencing and micro-Raman spectrometry were employed to analyze the microbial communities and microplastics of coastal sediment samples, respectively. We aimed to explore the ecological impact of MPs with small sizes (≤ 100 µm) in real coastal sediment environments. Our results revealed that as microplastic size decreased, the environmental behavior of MPs underwent alterations. In the coastal sediments, no significant correlations were observed between the detected MPs and the whole microbial communities, but small MPs posed potential hazards to eukaryotic communities. Moreover, these small MPs were more prone to microbial degradation and significantly affected carbon metabolism in the habitat. This study is the first to reveal the comprehensive impact of small MPs on microbial communities in a real coastal sediment environment.


Assuntos
Microbiota , Poluentes Químicos da Água , Microplásticos/toxicidade , Microplásticos/análise , Plásticos/análise , Sedimentos Geológicos/química , Poluentes Químicos da Água/toxicidade , Poluentes Químicos da Água/análise , Monitoramento Ambiental
18.
Water Sci Technol ; 67(3): 619-27, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23202568

RESUMO

Natural zeolite is a favorable NH(4)(+)-ion exchanger in the tertiary wastewater treatment. In this study, a natural Chinese zeolite was anatomized using the mercury injection method, X-ray diffraction, and scanning electron micrographs. The kinetic process of ammonium adsorption onto the zeolite was best described by the pseudo second order model; the adsorption equilibrium data fitted better to the Freundlich isotherm; and the exchange between ammonium and alkali/alkaline earth cations was in the order of Na(+) > Ca(2+) > K(+) > Mg(2+). Finally, the zeolite powder was applied for the tertiary treatment of coking wastewater, which still contained high concentration of ammonium after the secondary treatment by a sequencing batch reactor. The Box-Behnken design was used to design the experimental protocol, and the response surface methodology (RSM) was used for the optimization of adsorption factors. The RSM analysis showed the optimal adsorption factors as particle size, 0.03 mm; initial dosage of zeolite powder, 50.0 g/L; and contact time, 24 h. The highest ammonium removal rate was 75.0% predicted by the RMS. Considering settleability of the zeolite powder, the particle size of 0.25 mm was recommended in practice with a little loss of the ammonium removal: 70.9% as the RMS predicted.


Assuntos
Compostos de Amônio Quaternário/química , Águas Residuárias/química , Purificação da Água , Zeolitas/química , Adsorção , Coque , Resíduos Industriais , Cinética , Termodinâmica
19.
J Environ Sci (China) ; 25(11): 2265-71, 2013 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-24552055

RESUMO

The bacterial strain Paracoccus denitrificans W12, which could utilize pyridine as its sole source of carbon and nitrogen, was added into a membrane bioreactor (MBR) to enhance the treatment of a pharmaceutical wastewater. The treatment efficiencies investigated showed that the removal of chemical oxygen demand, total nitrogen, and total phosphorus were similar between bioaugmented and non-bioaugmented MBRs, however, significant removal of pyridine was obtained in the bioaugmented reactor. When the hydraulic retention time was 60 hr and the influent concentration of pyridine was 250-500 mg/L, the mean effluent concentration of pyridine without adding W12 was 57.2 mg/L, while the pyridine was degraded to an average of 10.2 mg/L with addition of W12. The bacterial community structure of activated sludge during the bioaugmented treatment was analyzed using polymerase chain reaction -denaturing gradient gel electrophoresis (PCR-DGGE). The results showed that the W12 inoculum reversed the decline of microbial community diversity, however, the similarity between bacterial community structure of the original sludge and that of the sludge after bioaugmentation decreased steadily during the wastewater treatment. Sequencing of the DNA recovered from DGGE gel indicated that Flavobacteriaceae sp., Sphingobium sp., Comamonas sp., and Hyphomicrobium sp. were the dominant organisms in time sequence in the bacterial community in the bioaugmented MBR. This implied that the bioaugmentation was affected by the adjustment of whole bacterial community structure in the inhospitable environment, rather than being due solely to the degradation performance of the bacterium added.


Assuntos
Reatores Biológicos , Indústria Farmacêutica , Membranas Artificiais , Paracoccus denitrificans/metabolismo , Piridinas/metabolismo , Eliminação de Resíduos Líquidos/métodos , Biodegradação Ambiental , Resíduos Industriais , Fatores de Tempo
20.
Environ Int ; 179: 108140, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37595537

RESUMO

Antibiotics are emerging pollutants that have detrimental effects on both target and non-target organisms in the environment. However, current methods for environmental risk assessment primarily focus on the risk to non-target organisms in ecosystems, overlooking a crucial risk of antibiotics - the induction of resistance in targeted bacteria. To address this oversight, we have incorporated resistance (R) risk with persistence, bioaccumulation and toxicity (PBT) to establish a more comprehensive PBTR (persistence, bioaccumulation, toxicity, and resistance) framework for antibiotic-specific risk assessment. Using the PBTR framework, we evaluated 74 antibiotics detected in Chinese seawater from 2000 to 2021, and identified priority antibiotics. Our analysis revealed that the priority antibiotics with R risk accounted for the largest proportion (50% to 70%), followed by P risk (40% to 58%), T risk (16% to 35%) and B risk (0 to 13%). To further categorize these priority antibiotics, we assigned them a risk level according to their fulfillment of criteria related to P, B, T, and R. Antibiotics meeting all four indicators were classified as Grade I, representing the highest risk level. Grade II and Grade III were assigned to antibiotics meeting three or two indicators, respectively. Antibiotics meeting only one indicator were classified as Grade IV, representing the lowest risk level. The majority of priority antibiotics fell into Grade IV, indicating low risk (55% to 79%), followed by Grade III (16% to 45%). The highest risk antibiotic identified in this study was clindamycin (CLIN), categorized as Grade II, in the East China Sea. Our findings aligned with previous studies for 25 antibiotics, affirming the validity of the PBTR framework. Moreover, we identified 13 new priority antibiotics, highlighting the advancement of this approach. This study provides a feasible screening strategy and monitoring recommendations for priority antibiotics in Chinese seawater.


Assuntos
Antibacterianos , Bioacumulação , Resistência Microbiana a Medicamentos , Água do Mar , Poluentes Químicos da Água , Antibacterianos/efeitos adversos , Antibacterianos/análise , Antibacterianos/farmacologia , Antibacterianos/toxicidade , Ecossistema , Água do Mar/análise , Poluição Química da Água , Poluentes Químicos da Água/efeitos adversos , Poluentes Químicos da Água/análise , Poluentes Químicos da Água/farmacologia , Poluentes Químicos da Água/toxicidade , China
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