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1.
Ecotoxicol Environ Saf ; 260: 115070, 2023 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-37257347

RESUMEN

Although antibiotics are one of the most significant factors contributing to the propagation of antibiotic resistance genes (ARGs), studies on the dose-response relationship at sub-lethal concentrations of antibiotics remain scarce, despite their importance for assessing the risks of antibiotics in the environment. In this study, we constructed a series of microcosms to investigate the propagation of intracellular (iARGs) and extracellular (eARGs) ARGs in both water and biofilms when exposed to antibiotics at various concentrations (1-100 µg/L) and frequencies. Results showed that eARGs were more abundant than iARGs in water, while iARGs were the dominant ARGs form in biofilms. eARGs showed differentiated dose-response relationships from iARGs. The abundance of iARGs increased with the concentration of antibiotics as enhanced selective pressure overcame the metabolic burden of antibiotic-resistant bacteria carrying ARGs. However, the abundance of eARGs decreased with increasing antibiotic concentrations because less ARGs were secreted from bacterial hosts at higher concentrations (100 µg/L). Furthermore, combined exposure to two antibiotics (tetracycline & imipenem) showed a synergistic effect on the propagation of iARGs, but an antagonistic effect on the propagation of eARGs compared to exposure to a single antibiotic. When exposed to antibiotic at a fixed total dose, one-time dosing (1 time/10 d) favored the propagation of iARGs, while fractional dosing (5 times /10 d) favored the propagation of eARGs. This study sheds light on the propagation of antibiotic resistance in the environment and can help in assessing the risks associated with the use of antibiotics.


Asunto(s)
Antibacterianos , Genes Bacterianos , Antibacterianos/farmacología , Tetraciclina , Farmacorresistencia Microbiana/genética , Bacterias , Agua
2.
J Environ Manage ; 326(Pt B): 116776, 2023 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-36435122

RESUMEN

Antibiotics are emerging pollutants largely considered to have a lower risk based on persistent, bioaccumulative, toxic (PBT) risk assessments. However, an increasing number of studies have illustrated that antibiotics are responsible for the global increase in antimicrobial resistance (AMR), which suggests that the risk of antibiotics has been largely underestimated by using PBT risk assessment. Here, we designed an integrated innovation risk assessment framework of persistent, bioaccumulative, toxic, and resistance (PBTR) that accounts for antibiotic resistance to better represent the antibiotic environmental risk. This novel antibiotic risk assessment framework was further verified via application to 39 target antibiotics in the 23 drinking water sources of the lower Yangtze River (LYR), China, during the normal and flood seasons. In contrast with the PBT assessment, single toxicity assessment and single resistance assessment, in the PBTR assessment, 7 of 39 target antibiotics with bacterial insensitivity were observed to represent a more prominent risk, as were the sites sampled during the flood season with low concentrations but high pollution loads, which confirmed that the sensitivity of PBTR risk assessment was instructive. The PBTR risk assessment for the screened priority antibiotics contributes not only representative data but also an innovative approach for identifying resistance risks. Using the positive matrix factorization (PMF) model, the sources of priority antibiotics can be predicted and thus supported the corresponding policy. Overall, this study first constructed a PBTR risk assessment framework, then applied it to facilitate the accurate management of antibiotic pollution at the basin level.


Asunto(s)
Agua Potable , Contaminantes Químicos del Agua , Agua Potable/análisis , Monitoreo del Ambiente , Antibacterianos/farmacología , Antibacterianos/análisis , Contaminantes Químicos del Agua/análisis , Ríos , Medición de Riesgo , China
3.
J Environ Sci (China) ; 129: 58-68, 2023 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-36804242

RESUMEN

Despite coastal mudflats serving as essential ecological zones interconnecting terrestrial/freshwater and marine systems, little is known about the profiles of antibiotic resistance genes (ARGs) in this area. In this study, characteristics of typical ARGs, involving both intracellular (iARGs) and extracellular ARGs (eARGs) at different physical states, were explored in over 1000 km of coastal mudflats in Eastern China. Results indicated the presence of iARGs and eARGs at states of both freely present or attached by particles. The abundance of eARGs was significantly higher than that of iARGs (87.3% vs 12.7%), and their dominance was more significant than those in other habitats (52.7%-76.3%). ARG abundance, especially for eARGs, showed an increasing trend (p < 0.05) from southern (Nantong) to northern (Lianyungang) coastal mudflats. Higher salinity facilitated the transformation from iARGs to eARGs, and smaller soil particle size was conducive to the persistence of eARGs in northern coastal mudflats. This study addresses the neglected function of coastal mudflats as eARGs reservoirs.


Asunto(s)
Antibacterianos , Genes Bacterianos , Antibacterianos/farmacología , Farmacorresistencia Microbiana/genética , Ecosistema , China
4.
Environ Sci Technol ; 56(23): 17166-17176, 2022 12 06.
Artículo en Inglés | MEDLINE | ID: mdl-36286344

RESUMEN

To advance the understanding of antibiotic resistance propagation from wastewater treatment plants, it is important to elucidate how different effluent disinfection processes affect the dissemination of predominantly extracellular antibiotic resistance genes (eARGs). Here, we show that, by facilitating proximal adsorption to recipient cells, bacterial debris generated by chlorination (but not by UV irradiation) increases the natural transformation frequency of their adsorbed eARG by 2.9 to 7.2-fold relative to free eARGs. This is because chlorination increases the bacterial surface roughness by 1.1 to 6.7-fold and the affinity toward eARGs by 1.6 to 5.8-fold, and 98% of the total eARGs released after chlorination were adsorbed to cell debris. In contrast, UV irradiation released predominantly free eARGs with 18% to 56% lower transformation frequency. The collision theory indicates that the ARG donor-recipient collision frequency increased by 35.1-fold for eARGs adsorbed onto chlorination-generated bacterial debris, and the xDLVO model infers a 29% lower donor-recipient contact energy barrier for these ARGs. Exposure to chlorination-generated bacterial debris also upregulated genes associated with natural transformation in Vibrio vulnificus (e.g., tfoX encoding the major activator of natural transformation) by 2.6 to 5.2-fold, likely due to the generation of chlorinated molecules (5.1-fold higher Cl content after chlorination) and persistent reactive species (e.g., carbon-centered radicals) on bacterial debris. Increased proximal eARG adsorption to bacterial debris was also observed in the secondary effluent after chlorination; this decreased eARG decay by 64% and increased the relative abundance of ARGs by 7.2-fold. Overall, this study highlights that different disinfection approaches can result in different physical states of eARGs that affect their resulting dissemination potential via transformation.


Asunto(s)
Desinfección , Halogenación , Adsorción , Aguas Residuales/microbiología , Farmacorresistencia Microbiana/genética , Genes Bacterianos , Bacterias/genética , Antibacterianos/farmacología
5.
Environ Monit Assess ; 194(9): 607, 2022 Jul 22.
Artículo en Inglés | MEDLINE | ID: mdl-35867174

RESUMEN

The health risk of antibiotic-resistant genes (ARGs) has been a global concern, while the report on occurrence and prevalence of ARGs in coastal zone is relatively scarce. This study investigated typical ARGs in soil and sediment in coastal line of eastern China and assessed its relationship with antibiotics and heavy metals as well as microbial community. Results showed that eight ARGs were all detected in the samples, and ß-lactam resistance gene blaTEM reached the highest absolute abundance (6.28 × 107 ~ 6.48 × 108 copies/g) and relative abundance (2.3 × 10-2 copies/16S rRNA) among samples. Amoxicillin and tetracycline were most frequently detected with the average concentration of 2.28 µg/kg and 3.48 µg/kg, respectively. Cr and Zn were found to be most abundant heavy metals with average value of 82.1 and 59.1 mg/kg, respectively. Proteobacteria, Campilobacterota, Bacteroidota, and Firmicutes were dominant phyla in most samples, while bacterial community varied significantly among samples. Redundancy analyses (RDA) showed that microbial community and antibiotics (amoxicillin and tetracycline) were driving factors of ARGs distribution, while heavy metals were not significantly correlated with ARGs. This study is helpful to understand the fate of ARGs in coastal zone.


Asunto(s)
Metales Pesados , Microbiota , Amoxicilina/análisis , Antibacterianos/farmacología , China , Farmacorresistencia Microbiana/genética , Monitoreo del Ambiente , Genes Bacterianos , Metales Pesados/análisis , ARN Ribosómico 16S/genética , Suelo , Tetraciclina/análisis
6.
Environ Sci Technol ; 54(7): 4621-4630, 2020 04 07.
Artículo en Inglés | MEDLINE | ID: mdl-32150399

RESUMEN

There is a growing need to mitigate the discharge of extracellular antibiotic resistance genes (ARGs) from municipal wastewater treatment systems. Here, molecularly-imprinted graphitic carbon nitride (MIP-C3N4) nanosheets were synthesized for selective photocatalytic degradation of a plasmid-encoded ARG (blaNDM-1, coding for multidrug resistance New Delhi metallo-ß-lactamase-1) in secondary effluent. Molecular imprinting with guanine enhanced ARG adsorption, which improved the utilization of photogenerated oxidizing species to degrade blaNDM-1 rather than being scavenged by background nontarget constituents. Consequently, photocatalytic removal of blaNDM-1 in secondary effluent with MIP-C3N4 (k = 0.111 ± 0.028 min-1) was 37 times faster than with bare graphitic carbon nitride (k = 0.003 ± 0.001 min-1) under UVA irradiation (365 nm, 3.64 × 10-6 Einstein/L·s). MIP-C3N4 can efficiently catalyze the fragmentation of blaNDM-1, which decreased the potential for ARG repair by transformed bacteria. Molecular imprinting also changed the primary degradation pathway; electron holes (h+) were the predominant oxidizing species responsible for blaNDM-1 removal with MIP-C3N4 versus free radicals (i.e., ·OH and O2-) for coated but nonimprinted C3N4. Overall, MIP-C3N4 efficiently removed blaNDM-1 from secondary effluent, demonstrating the potential for molecular imprinting to enhance the selectivity and efficacy of photocatalytic processes to mitigate dissemination of antibiotic resistance from sewage treatment systems.


Asunto(s)
Antibacterianos , Nitrilos , Adsorción , Farmacorresistencia Microbiana , Grafito , Compuestos de Nitrógeno
7.
Ecotoxicol Environ Saf ; 161: 251-259, 2018 10.
Artículo en Inglés | MEDLINE | ID: mdl-29886312

RESUMEN

The livestock wastewater treatment plant represents an important reservoir of antibiotic resistance determinants in the environment. The study explored the prevalence of five antibiotic resistance genes (ARGs, including sulI, tetA, qnrD, mphB and mcr-1) and class 1 integron (intI1) in a typical livestock wastewater treatment plant, and analyzed their integrated association with two metal resistance genes (copA and czcA), two pathogens genes (Staphylococcus and Campylobacter), bacterial community and wastewater properties. Results indicated that all investigated genes were detected in the plant. The treatment plant could not completely remove ARGs abundances, with up to 2.2 × 104~3.7 × 108 copies/L of them remaining in the effluent. Mcr-1 was further enriched by 27-fold in the subsequent pond. The correlation analysis showed that mphB significantly correlateed with tetA and intI. Mcr-1 strongly correlated with copA. MphB and intI significantly correlated with czcA. The correlations implied a potential co-selection risk of bacterial resistant to antibiotics and metals. Redundancy analyses indicated that qnrD and mcr-1 strongly correlated with 13 and 14 bacterial genera, respectively. Most ARGs positively correlated to wastewater nutrients, indicating that an efficient reduction of wastewater nutrients would contribute to the antibiotic resistance control. The study will provide useful implications on fates and reductions of ARGs in livestock facilities and receiving environments.


Asunto(s)
Antibacterianos/análisis , Farmacorresistencia Microbiana/genética , Genes Bacterianos , Metales Pesados/análisis , Aguas Residuales/microbiología , Purificación del Agua , Animales , Bacterias/efectos de los fármacos , Bacterias/genética , Integrones , Porcinos , Aguas Residuales/análisis
9.
Biodegradation ; 27(2-3): 95-106, 2016 06.
Artículo en Inglés | MEDLINE | ID: mdl-26931341

RESUMEN

Given the increasing discoveries related to the eco-toxicity of titanium dioxide (TiO2) nanoparticles (NPs) in different ecosystems and with respect to public health, it is important to understand their potential effects in drinking water treatment (DWT). The effects of TiO2 NPs on ammonia reduction, ammonia-oxidizing archaea (AOA) and ammonia-oxidizing bacteria (AOB) in biological activated carbon (BAC) filters for drinking water were investigated in static and dynamic states. In the static state, both the nitrification potential and AOB were significantly inhibited by 100 µg L(-1) TiO2 NPs after 12 h (p < 0.05), and the threshold decreased to 10 µg L(-1) with prolonged exposure (36 h, p < 0.05). However, AOA were not considerably affected in any of the tested conditions (p > 0.05). In the dynamic state, different amounts of TiO2 NP pulses were injected into three pilot-scale BAC filters. The decay of TiO2 NPs in the BAC filters was very slow. Both titanium quantification and scanning electron microscope analysis confirmed the retention of TiO2 NPs in the BAC filters after 134 days of operation. Furthermore, the TiO2 NP pulses considerably reduced the performance of ammonia reduction. This study identified the retention of TiO2 NPs in BAC filters and the negative effect on the ammonia reduction, suggesting a potential threat to DWT by TiO2 NPs.


Asunto(s)
Amoníaco/metabolismo , Agua Potable/análisis , Nanopartículas/análisis , Titanio/análisis , Purificación del Agua/métodos , Archaea/metabolismo , Biodegradación Ambiental , Carbón Orgánico , Filtración
10.
Environ Sci Technol ; 49(9): 5771-8, 2015 May 05.
Artículo en Inglés | MEDLINE | ID: mdl-25853586

RESUMEN

Growing attention has been paid to the dissemination of antibiotic resistance genes (ARGs) in wastewater microbial communities; however, the disinfection processes, as microbial control technologies, have not been evaluated for their impacts on ARGs transfer. In this study, the effects of ultraviolet (UV) disinfection and chlorination on the frequency of ARGs transfer have been explored based on the conjugative transfer model between Gram-negative strains of E. coli. The results indicated that UV disinfection and chlorination exhibit distinct influences on the conjugative transfer. Low UV doses (up to 8 mJ/cm2) had little influence on the frequency of conjugative transfer, and UV exposure only decreased the bacterial number but did not change the cell permeability. By comparison, low chlorine doses (up to 40 mg Cl min/L) significantly promoted the frequency of conjugative transfer by 2-5-fold. The generated chloramine stimulated the bacteria and improved the cell permeability. More pilus were induced on the surface of conjugative cells, which acted as pathways for ARGs transfer. The frequency of ARG transfers was greatly suppressed by high doses of UV (>10 mJ/cm2) or chlorine (>80 mg Cl min/L).


Asunto(s)
Farmacorresistencia Microbiana/genética , Escherichia coli/genética , Transferencia de Gen Horizontal/efectos de la radiación , Genes Bacterianos , Halogenación/efectos de la radiación , Rayos Ultravioleta , Aguas Residuales/microbiología , Antibacterianos/farmacología , Conjugación Genética , Desinfección , Relación Dosis-Respuesta en la Radiación , Farmacorresistencia Microbiana/efectos de la radiación , Escherichia coli/efectos de la radiación , Escherichia coli/ultraestructura , L-Lactato Deshidrogenasa/metabolismo , Viabilidad Microbiana/efectos de la radiación
11.
Chemosphere ; 360: 142434, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38797215

RESUMEN

As emerging contaminants, antibiotics are frequently present in various environments, particularly rivers, albeit often at sublethal concentrations (ng/L∼µg/L). Assessing the risk associated with these low levels, which are far below the lethal threshold for most organisms, remains challenging. In this study, using microcosms containing planktonic bacteria and biofilm, we examined how antibiotic resistance genes (ARGs) in different physical states, including intracellular ARGs (iARGs) and extracellular ARGs (eARGs) responded to these low-level antibiotics. Our findings reveal a positive correlation between sub-lethal antibiotic exposure (ranging from 0.1 to 10 µg/L) and increased prevalence (measured as ARG copies/16s rDNA) of both iARGs and eARGs in planktonic bacteria. Notably, eARGs demonstrated greater sensitivity to antibiotic exposure compared to iARGs, with a lower threshold (0.1 µg/L for eARGs versus 1 µg/L for iARGs) for abundance increase. Moreover, ARGs in biofilms demonstrates higher sensitivity to antibiotic exposure compared to planktonic bacteria. To elucidate the underlying mechanisms, we established an integrated population dynamics-pharmacokinetics-pharmacodynamics (PD-PP) model. This model indicates that the enhanced sensitivity of eARGs is primarily driven by an increased potential for plasmid release from cells under low antibiotic concentrations. Furthermore, the accumulation of antibiotic in biofilms induces a greater sensitivity of ARG compared to the planktonic bacteria. This study provides a fresh perspective on the development of antibiotic resistance and offers an innovative approach for assessing the risk of sublethal antibiotic in the environment.


Asunto(s)
Antibacterianos , Bacterias , Biopelículas , Farmacorresistencia Microbiana , Antibacterianos/farmacología , Antibacterianos/toxicidad , Biopelículas/efectos de los fármacos , Farmacorresistencia Microbiana/genética , Bacterias/efectos de los fármacos , Bacterias/genética , Genes Bacterianos , Plancton/efectos de los fármacos , Plancton/genética , Farmacorresistencia Bacteriana/genética , Contaminantes Químicos del Agua/toxicidad
12.
Nutrients ; 16(12)2024 Jun 14.
Artículo en Inglés | MEDLINE | ID: mdl-38931219

RESUMEN

To investigate the changes in the intestinal flora in the Chinese elderly with cardiovascular disease (CVD) and its correlation with the metabolism of trimethylamine (TMA), the intestinal flora composition of elderly individuals with CVD and healthy elderly individuals was analyzed using 16S rRNA sequencing, the TMA levels in the feces of elderly were detected using headspace-gas chromatography (HS-GC), and four kinds of characterized TMA-producing intestinal bacteria in the elderly were quantified using real-time fluorescence quantitative polymerase chain reaction (qPCR). The results showed that Firmicutes, Actinobacteria, Proteobacteria, Bacteroidetes, and Verrucomicrobia are the dominant microorganisms of the intestinal flora in the Chinese elderly. And there were significant differences in the intestinal bacteria composition between healthy elderly individuals and those with CVD, accompanied by a notable difference in the TMA content. The richness and diversity of the intestinal flora in the elderly with CVD were higher than those in the healthy elderly. Correlation analysis indicated that certain significantly different intestinal flora were associated with the TMA levels. Our findings showed a significant difference in TMA-producing intestinal flora between healthy elderly individuals and those with CVD. The TMA levels were found to be positively and significantly correlated with Klebsiella pneumoniae, suggesting that this bacterium is closely linked to the production of TMA in the elderly gut. This may have implications for the development and progression of CVD in the elderly population.


Asunto(s)
Enfermedades Cardiovasculares , Heces , Microbioma Gastrointestinal , Metilaminas , Humanos , Metilaminas/metabolismo , Anciano , Masculino , Femenino , Enfermedades Cardiovasculares/microbiología , Heces/microbiología , China , ARN Ribosómico 16S/genética , Bacterias/clasificación , Bacterias/metabolismo , Bacterias/genética , Bacterias/aislamiento & purificación , Persona de Mediana Edad , Pueblo Asiatico , Anciano de 80 o más Años , Pueblos del Este de Asia
13.
Front Microbiol ; 15: 1367630, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38952444

RESUMEN

Purpose: To investigate the therapeutic efficiency of a novel drink termed "Ferment" in cases of ulcerative colitis (UC) and its influence on the gut microbiota. Method: In this study, we developed a complex of mixed fruit juice and lactic acid bacteria referred to as Ferment. Ferment was fed to mice for 35 days, before inducing UC with Dextran Sulfate Sodium Salt. We subsequently investigated the gut microbiome composition using 16S rRNA sequencing. Result: After Ferment treatment, mouse body weight increased, and animals displayed less diarrhea, reduced frequency of bloody stools, and reduced inflammation in the colon. Beneficial bacteria belonging to Ileibacterium, Akkermansia, and Prevotellacea were enriched in the gut after Ferment treatment, while detrimental organisms including Erysipelatoclostridium, Dubosiella, and Alistipes were reduced. Conclusion: These data place Ferment as a promising dietary candidate for enhancing immunity and protecting against UC.

14.
Foods ; 13(6)2024 Mar 18.
Artículo en Inglés | MEDLINE | ID: mdl-38540911

RESUMEN

The impact of five human milk oligosaccharides (HMOs)-2'-fucosyllactose (2FL), 3'-sialyllactose (3SL), 6'-sialyllactose (6SL), lacto-N-tetraose (LNT), and lacto-N-neotetraose (LNnT)-on the gut microbiota and short-chain fatty acid (SCFA) metabolites in infants aged 0-6 months was assessed through in vitro fermentation. Analyses of the influence of different HMOs on the composition and distribution of infant gut microbiota and on SCFA levels were conducted using 16S rRNA sequencing, quantitative real-time PCR (qPCR), and gas chromatography (GC), respectively. The findings indicated the crucial role of the initial microbiota composition in shaping fermentation outcomes. Fermentation maintained the dominant genera species in the intestine but influenced their abundance and distribution. Most of the 10 Bifidobacteria strains effectively utilized HMOs or their degradation products, particularly demonstrating proficiency in utilizing 2FL and sialylated HMOs compared to non-fucosylated neutral HMOs. Moreover, our study using B. infantis-dominant strains and B. breve-dominant strains as inocula revealed varying acetic acid levels produced by Bifidobacteria upon HMO degradation. Specifically, the B. infantis-dominant strain yielded notably higher acetic acid levels than the B. breve-dominant strain (p = 0.000), with minimal propionic and butyric acid production observed at fermentation's conclusion. These findings suggest the potential utilization of HMOs in developing microbiota-targeted foods for infants.

15.
Breastfeed Med ; 19(3): 208-216, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38489527

RESUMEN

Background: Lactoferrin (LF) is a multifunctional glycoprotein found in human milk and body fluids, which has been shown to play a vital role in regulating the immunity and supporting the intestinal health of infants. Aim: This study evaluated the association between maternal/parturient factors and LF concentration in the breast milk of Chinese mothers. Methods: 207 breast milk samples were collected from healthy mothers with in the first year of lactation. Maternal and parturient information was collected for these participants through questionnaires. The content of lactoferrin in breast milk was detected by liquid chromatography, and macronutrient concentration in breast milk was measured by human milk analyzer in only 109 samples. Results: Our findings demonstrated that the LF content was much higher within the first month of lactation than it was after that period (p < 0.05). When compared with normal and lean mothers, the LF content of obese mothers was considerably higher (p < 0.05). The parity and LF content showed a favorable correlation. The proportion of LF to total protein tended to decrease as lactation progressed. Protein, fat, dry matter, and energy content were significantly positively correlated with LF content (p < 0.001). Conclusion: Early breast milk tends to have a higher level of LF, and the change of LF concentration in breast milk is associated with the parity and body mass index of the mother.


Asunto(s)
Lactoferrina , Leche Humana , Embarazo , Lactante , Femenino , Humanos , Leche Humana/química , Lactoferrina/análisis , Índice de Masa Corporal , Lactancia Materna , Lactancia/fisiología , Paridad
16.
Environ Technol ; : 1-11, 2023 Sep 04.
Artículo en Inglés | MEDLINE | ID: mdl-37615415

RESUMEN

The composting performance and nitrogen transformation during membrane-covered aerobic composting of kitchen waste were investigated. The aerobic composting products of the kitchen waste had a high seed germination index of ∼180%. The application of the membrane increased the mean temperature in the early cooling stage of composting by 4.5℃, resulted in a lower moisture content, and reduced the emissions of NH3 and N2O by 48.5% and 44.1%, respectively, thereby retaining 7.9% more nitrogen in the compost. The adsorption of the condensed water layer under inner-membrane was the reason for reducing NH3 emissions, and finite element modeling revealed that the condensed water layer was present throughout the composting process with a maximum thickness of ∼2 mm in the thermophilic stage. The reduction of N2O emissions was related to the micro-positive pressure in the reactor, which promoted the distribution of oxygen, thus weakening denitrification. In addition, the membrane cover decreased the diversity of the bacterial community and increased the diversity of ammonia-oxidizing strains. This study confirmed that membrane-covered composting was suitable for kitchen waste management and could be used as a strategy to mitigate NH3 and N2O emissions.

17.
Sci Total Environ ; 856(Pt 2): 159092, 2023 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-36174705

RESUMEN

Global consumption and discharge of antibiotics have led to the rapid development and spread of bacterial antibiotic resistance. Among treatment strategies, electrochemical advanced oxidation processes (EAOPs) are gaining popularity for treating water/wastewater containing antibiotics due to their high efficiency and easiness of operation. In this review, we summarize various forms of EAOPs that contribute to antibiotic degradation, including common electrochemical oxidation (EO), electrolyte enhanced EO, electro-Fenton (EF) processes, EF-like process, and EAOPs coupling with other processes. Then we assess the performance of various EAOPs in antibiotic degradation and discuss the influence of key factors, including electrode, initial concentration and type of antibiotic, operation conditions, electrolyte, and water quality. We also review mechanisms and degradation pathways of various antibiotics degradation by EAOPs, and address the species and toxicity of intermediates produced during antibiotics treatment. Finally, we highlight challenges and critical research needs to facilitate the application of EAOPs in antibiotic treatment.


Asunto(s)
Antibacterianos , Contaminantes Químicos del Agua , Contaminantes Químicos del Agua/análisis , Peróxido de Hidrógeno , Técnicas Electroquímicas , Aguas Residuales , Oxidación-Reducción , Electrodos
18.
Environ Sci Pollut Res Int ; 30(27): 71371-71381, 2023 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-37162672

RESUMEN

In order to preliminarily explore the distribution of antibiotic pollution in the coastal waters of eastern China, the concentrations of 13 antibiotics in 5 representative coastal rivers in Jiangsu and 21 sampling sites in the coastal waters of Jiangsu were analyzed. The total antibiotic concentrations in the 5 rivers ranged from 33.14 to 417.78 ng L-1, and the total antibiotic concentrations in the 21 sampling sites ranged from 0.90 to 86.33 ng L-1. Macrolides exhibited the highest total concentration and the maximum detection frequency in both coastal rivers and the coastal waters. The concentrations of antibiotics in a sampling site decreased as the distance of the sampling site from the coastline increased, indicating that river inputs are important sources of antibiotic pollution in the coastal waters of Jiangsu. The detection frequencies of roxithromycin, lincomycin, azithromycin, and sulfamethoxazole in the rivers and sampling sites were above 70%. Correlation analysis showed that the concentrations of antibiotics were positively correlated with the levels of chemical oxygen demand, total phosphorus, and total nitrogen. Risk assessments revealed that roxithromycin and ofloxacin posed medium ecological and resistance risks, respectively, to the most sensitive aquatic organisms in the coastal waters of Jiangsu. The results of this study highlight the significance of monitoring and controlling the concentrations of antibiotic contaminants in the coastal waters of Jiangsu.


Asunto(s)
Roxitromicina , Contaminantes Químicos del Agua , Antibacterianos/análisis , Contaminantes Químicos del Agua/análisis , Monitoreo del Ambiente/métodos , China , Medición de Riesgo , Ríos/química
19.
Mar Environ Res ; 188: 105992, 2023 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-37094527

RESUMEN

Offshore areas are particularly important in recognizing microplastics pollution because they are sinks of land imports and sources of ocean microplastics. This study investigated the pollution and distribution of microplastics in the offshore Sea, rivers and wastewater treatment plants (WWTPs) in Jiangsu coastal area in China. Results showed that microplastics were widely present in the offshore area, with an average abundance of 3.1-3.5 items/m3. Significantly higher abundance was present in rivers (3.7-5.9 item/m3), municipal WWTPs (13.7 ± 0.5 item/m3), and industrial WWTPs (19.7 ± 1.2 item/m3). The proportion of small-sized microplastics (1-3 mm) increased from WWTPs (53%) to rivers (64%) and the offshore area (53%). Polyamide (PA), polyethylene (PE), polyvinyl chloride (PVC), polypropylene (PP), polystyrene (PS), and rayon (RA) were dominant types of microplastics. Both living and industrial sources contributed to the prevalent microplastics in the offshore Sea. Redundancy analysis showed that small-sized microplastics (1-3 mm) were positively correlated to total phosphorus (TP), while large-sized microplastics (3-5 mm) were positively correlated to TP and NH3-N. The abundance of PE, PP and PVC microplastics were positively correlated to TP and total nitrogen (TN), thus nutrients could be indicators of microplastics pollution in the offshore area.


Asunto(s)
Microplásticos , Contaminantes Químicos del Agua , Plásticos , Ríos , Contaminantes Químicos del Agua/análisis , Monitoreo del Ambiente/métodos , Polipropilenos/análisis , China , Polietileno/análisis
20.
J Chromatogr A ; 1710: 464435, 2023 Nov 08.
Artículo en Inglés | MEDLINE | ID: mdl-37820461

RESUMEN

Phospholipids (PLs) are important and complex trace lipids in milk, which have positive effects on the infants' nervous and immune system development. Herein, a new method for selective extraction of PLs using glass fabric @ MOF-808 was proposed. Based on Lewis acid-base interaction, MOF-808 containing abundant Zr-OH groups was selected as the adsorption body, and glass fabric was used as a substrate to make the adsorbent easy to remove and reuse. The influencing factors such as loading solution, extraction time, eluent and elution time were further investigated. The adsorbent showed high adsorption capacity (3.31-6.54 mg/g for PLs) and good reusability (reused at least five times). The method showed low detection limits (1.61 µg/L - 10.24 µg/L) and quantification limits (5.24 µg/L-51.21 µg/L) for eight classes of PLs. The analysis of PLs in human milk at different lactation stages by ultra-high performance liquid chromatography-quadrupole time-of-flight mass spectrometry could obtain up to 206 PLs, indicating that the method has extremely high extraction and anti-interference capabilities. This work is the first time to introduce MOF materials to selectively extract PLs and use glass fabric as a substrate for MOF-808, which has the advantages of easy recovery and high sensitivity. It provides technical support for the discovery of more PL species and has potential applications in phospholipidomics.


Asunto(s)
Estructuras Metalorgánicas , Leche Humana , Humanos , Leche Humana/química , Fosfolípidos/química , Estructuras Metalorgánicas/química , Circonio/química , Cromatografía Líquida de Alta Presión/métodos , Extracción en Fase Sólida/métodos
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