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1.
Adv Neurobiol ; 29: 117-162, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36255674

RESUMO

Proteoglycans, and especially their GAG components, participate in numerous biologically significant interactions with growth factors, chemokines, morphogens, guidance molecules, survival factors, and other extracellular and cell-surface components. These interactions are often critical to the basic developmental processes of cellular proliferation and differentiation, as well as to both the onset of disease sequelae and prevention of disease progression. In many tissues, proteoglycans and especially their glycosaminoglycan (GAG) components are mediators of these processes. The GAG family is characterized by covalently linked repeating disaccharides forming long unbranched polysaccharide chains. Thus far in higher eukaryotes, the family consists of chondroitin sulfate (CS), heparin/heparan sulfate (HS), dermatan sulfate (DS), keratan sulfate (KS) and hyaluronan (HA). All GAG chains (except HA) are characteristically modified by varying amounts of esterified sulfate. One or more GAG chains are usually found in nature bound to polypeptide backbones in the form of proteoglycans; HA is the exception. In the nervous system, GAG/proteoglycan-mediated interactions participate in proliferation and synaptogenesis, neural plasticity, and regeneration. This review focuses on the structure, chemistry and function of GAGs in nervous system development, disease, function and injury response.


Assuntos
Sulfatos de Condroitina , Glicosaminoglicanos , Humanos , Glicosaminoglicanos/metabolismo , Sulfatos de Condroitina/química , Sulfatos de Condroitina/metabolismo , Dermatan Sulfato , Sulfato de Ceratano , Ácido Hialurônico , Heparitina Sulfato/metabolismo , Proteoglicanas , Heparina , Dissacarídeos , Sulfatos/metabolismo , Sistema Nervoso
2.
J Environ Sci (China) ; 124: 319-329, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36182142

RESUMO

Experiments were performed to explore the impact of sulfur nanoparticles (SNPs) on growth, Cu accumulation, and physiological and biochemical responses of oilseed rape (Brassica napus L.) inoculated with 5 mg/L Cu-amended MS medium supplemented with or without 300 mg/L SNPs exposure. Cu exerted severe phytotoxicity and inhibited plant growth. SNPs application enhanced the shoot height, root length, and dry weight of shoot and root by 34.6%, 282%, 41.7% and 37.1%, respectively, over Cu treatment alone, while the shoot and root Cu contents and Cu-induced lipid perodixation as the malondialdehyde (MDA) levels in shoots and roots were decreased by 37.6%, 35%, 28.4% and 26.8%. Further, the increases in superoxide dismutase (SOD), peroxidase (POD), catalase (CAT), ascorbate peroxidase (APX), glutathione reductase (GR) and glutathione S-transferase (GST) enzyme activities caused by Cu stress were mitigated in shoots (10.9%-37.1%) and roots (14.6%-35.3%) with SNPs addition. SNPs also positively counteracted the negative effects on shoot K, Ca, P, Mg, Mn, Zn and Fe contents and root K, Ca, Mg and Mn contents from Cu exposure alone, and significantly promoted the nutrients accumulation in plant. Additionally, in comparison with common bulk sulfur particles (BSPs) and sulfate, SNPs showed more positive effects on promoting growth in shoots (6.7% and 19.5%) and roots (10.9% and 15.1%), as well as lowering the shoot Cu content (40.1% and 43.3%) under Cu stress. Thus, SNPs application has potential to be a green and sustainable technology for increasing plant productivity and reducing accumulation of toxic metals in heavy metal polluted soils.


Assuntos
Brassica napus , Metais Pesados , Nanopartículas , Antioxidantes/metabolismo , Ascorbato Peroxidases/metabolismo , Brassica napus/metabolismo , Catalase/metabolismo , Glutationa Redutase/metabolismo , Glutationa Redutase/farmacologia , Glutationa Transferase , Peróxido de Hidrogênio , Lipídeos/farmacologia , Malondialdeído , Metais Pesados/farmacologia , Estresse Oxidativo , Peroxidases , Raízes de Plantas/metabolismo , Solo , Sulfatos , Enxofre , Superóxido Dismutase/metabolismo
3.
J Environ Sci (China) ; 124: 350-359, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36182144

RESUMO

Sulfite (SO32-) activation is one of the most potential sulfate-radical-based advanced oxidation processes, and the catalysts with high efficiency and low-cost are greatly desired. In this study, the cobalt nanoparticles embedded in nitrogen-doped graphite layers (Co@NC), were used to activate SO32- for removal of Methyl Orange in aqueous solution. The Co@NC catalysts were synthesized via pyrolysis of Co2+-based metal-organic framework (Co-MOF), where CoO was firstly formed at 400℃ and then partially reduced to Co nanoparticles embedded in carbon layers at 800℃. The Co@NC catalysts were more active than other cobalt-based catalysts such as Co2+, Co3O4 and CoFe2O4, due to the synergistic effect of metallic Co and CoxOy. A series of chain reaction between Co species and dissolved oxygen was established, with the production and transformation of SO3•-, SO52-, and subsequent active radicals SO4•- and HO•. In addition, HCO3- was found to play a key role in the reaction by complexing with Co species on the surface of the catalysts. The results provide a new promising strategy by using the Co@NC catalyst for SO32- oxidation to promote organic pollutants degradation.


Assuntos
Poluentes Ambientais , Grafite , Estruturas Metalorgânicas , Nanopartículas , Carbono , Cobalto , Nitrogênio , Óxidos , Oxigênio , Sulfatos , Sulfitos
4.
J Ethnopharmacol ; 301: 115853, 2023 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-36272493

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: Scutellaria baicalensis Georgi. contains varieties of function compounds, and it has been used as traditional drug for centuries. Baicalein is the highest amount of flavonoid found in Scutellaria baicalensis Georgi., which exerts various pharmacological activities and might be a promising drug to treat COVID-19. AIM OF THE STUDY: The present work aims to investigate the metabolism of baicalein in humans after oral administration, and study the pharmacokinetics of BA and its seven metabolites in plasma and urine. MATERIALS AND METHODS: The metabolism profiling and the identification of baicalein metabolites were performed on HPLC-Q-TOF. Then a column-switching method named MPX™-2 system was applied for the high-throughput quantificationof BA and seven metabolites. RESULTS: Seven metabolites were identified using HPLC-Q-TOF, including sulfate, glucuronide, glucoside, and methyl-conjugated metabolites. Pharmacokinetic study found that BA was extensively metabolized in vivo, and only 5.65% of the drug remained intact in the circulatory system after single dosing. Baicalein-7-O-sulfate and baicalein-6-O-glucuronide-7-O-glucuronide were the most abundant metabolites. About 7.2% of the drug was excreted through urine and mostly was metabolites. CONCLUSION: Seven conjugated metabolites were identified in our assay. A high-throughput HPLC-MS/MS method using column switch was established for quantifying BA and its metabolites. The method has good sensitivity and reproducibility, and successfully applied for the clinical pharmacokinetic study of baicalein and identified metabolites. We expect that our results will provide a metabolic and pharmacokinetic foundation for the potential application of baicalein in medicine.


Assuntos
COVID-19 , Flavanonas , Humanos , Espectrometria de Massas em Tandem/métodos , Glucuronídeos , Reprodutibilidade dos Testes , Scutellaria baicalensis , Cromatografia Líquida de Alta Pressão , Flavonoides/farmacocinética , Sulfatos
5.
Sci Total Environ ; 855: 158875, 2023 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-36126708

RESUMO

We investigate responses of sulfate (SO42-) and nitrate (NO3-) to anthropogenic emission changes in 2006-2017 by fixing meteorology at the 2009 level using nested 3D chemical transport model GEOS-Chem. We find that sulfate concentration decreases following SO2 emissions, but with a relatively smaller reduction rate (by 16 % in North China Plain (NCP) and 28 % in Yangtze River Delta (YRD)) due to larger sulfur oxidation ratio (SOR) at lower SO2 level. SOR follows a power law with SO2 emissions in general except in winter in NCP, when and where both SO2 emission reduction and atmospheric oxidation capacity are critical to the inter-annual variations of SOR. Nitrate concentration ([pNO3-]) decreases along with NOx emission reduction in summer, but increases slightly in winter in 2011-2017. Equilibrium with gas phase HNO3, NO3- in particle phase (pNO3-) is determined by total HNO3 (TN = [pNO3-] + [gHNO3]) oxidized from NO2 and gas-particle partitioning (ε(NO3-) = [pNO3-]/TN). TN is decreasing faster in summer (~33 %) than in winter (~25 %) in 2011-2017. In contrast, ε(NO3-) changes marginally in summer (within 5 %) but increases by 36 % in NCP and by 51 % in YRD in winter in 2006-2017. The increasing of ε(NO3-) in winter is attributed to the strong reduction of [pSO42-], which increases the relative abundance of NH3 and thus favors partitioning of NO3- to the particle phase. The effect of increasing ε(NO3-) overcomes that of decreasing TN in winter. We suggest reduce SO2 emissions to further reduce [pSO42-] in eastern China. In addition, we recommend reduce NOx emissions in summer, and reduce atmospheric oxidation capacity and relative abundance of NH3 in winter to reduce [pNO3-].


Assuntos
Poluentes Atmosféricos , Poluentes Atmosféricos/análise , Material Particulado/análise , Nitratos/análise , Sulfatos/análise , Monitoramento Ambiental , Óxidos de Nitrogênio/análise , Estações do Ano , Óxidos de Enxofre , China
6.
Sci Total Environ ; 856(Pt 1): 158840, 2023 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-36122729

RESUMO

The sea spray effect can severely influence the isotopic signature of terrestrial individuals in coastal regions. To further specify this effect, beach grass was grown in a greenhouse under controlled environmental conditions and sprayed with mineral salt solution containing different mineral salts but only traces of NaCl (group 1). Another group of plants was sprayed with salty water from the Schlei inlet and the Baltic Sea, respectively (group 2). Control plants were only sprayed with tap water. Isotope analyses were conducted on the unwashed and washed plants (δ13Ccellulose, δ18Ocellulose, δ34Stotal S, 87Sr/86Sr), soil (δ18Osulfate, δ34Ssulfate, 87Sr/86Sr), and spray as well as irrigation water (δ18Osulfate, δ34Ssulfate, 87Sr/86Sr). Moreover, elemental analyses were performed on the water samples. The sea spray effect was visible in all isotopic systems under study. The uptake of SO42-, HCO3-, and Sr2+ directly affected plants of group 1, while plants of group 2, sprayed with salty water, additionally showed salinity stress in the case of α-cellulose and total sulfur due to biochemical reactions of the plants. Very high concentrations in HCO3- or SO42- also affected the plants' isotopic signatures. The impact of the sea spray and additional stress reactions were quantified. Our study is the first experiment creating an artificial sea spray effect in a greenhouse. This experiment for the first time enables the identification and quantification of the sea spray effect in environmental samples. The marine signature taken up by the plants and recorded by the investigated isotopic systems is apparently high and should have an impact on the isotopic fingerprints of animal consumers at the coast, as evidenced for archaeological animals from the Viking Haithabu and the early medieval Schleswig sites located close to the Baltic Sea. This result demonstrates the potential of greenhouse experiments as an isotopic predictor of the past local sea spray effect.


Assuntos
Poaceae , Enxofre , Animais , Água , Celulose , Sulfatos , Minerais
7.
J Hazard Mater ; 442: 130057, 2023 01 15.
Artigo em Inglês | MEDLINE | ID: mdl-36179622

RESUMO

Peatlands are generally important sources of methylmercury (MeHg) to adjacent aquatic ecosystems, increasing the risk of human and wildlife exposure to this highly toxic compound. While microorganisms play important roles in mercury (Hg) geochemical cycles where they directly and indirectly affect MeHg formation in peatlands, potential linkages between net MeHg formation and microbial communities involving these microorganisms remain unclear. To address this gap, microbial community composition and specific marker gene transcripts were investigated along a trophic gradient in a geographically constrained peatland chronosequence. Our results showed a clear spatial pattern in microbial community composition along the gradient that was highly driven by peat soil properties and significantly associated with net MeHg formation as approximated by MeHg concentration and %MeHg of total Hg concentration. Known fermentative, syntrophic, methanogenic and iron-reducing metabolic guilds had the strong positive correlations to net MeHg formation, while methanotrophic and methylotrophic microorganisms were negatively correlated. Our results indicated that sulfate reducers did not have a key role in net MeHg formation. Microbial activity as interpreted from 16S rRNA sequences was significantly correlated with MeHg and %MeHg. Our findings shed new light on the role of microbial community in net MeHg formation of peatlands that undergo ontogenetic change.


Assuntos
Mercúrio , Compostos de Metilmercúrio , Microbiota , Humanos , Compostos de Metilmercúrio/metabolismo , RNA Ribossômico 16S/genética , Mercúrio/análise , Solo/química , Sulfatos , Ferro
8.
Methods Mol Biol ; 2597: 159-176, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36374421

RESUMO

Glycosaminoglycans (GAGs) are long, linear polysaccharides that are ubiquitously expressed on the cell surface and in the extracellular matrix of all animal cells. These complex carbohydrates are composed of alternating glucosamine and uronic acids that can be heterogeneously N- and O-sulfated. The arrangement and orientation of the sulfated sugar residues specify the location of distinct ligand binding sites on the cell surface, and their capacity to bind ligands impacts cell growth and development, the ability to form tissues and organs, and normal physiology. The heterogeneous nature of GAGs and their inherent structural diversity across different tissues, cell types, and disease states creates challenges to characterizing their structure and function. Here, we describe detailed methods to investigate GAG-protein interactions in vitro and evaluate the structural composition of two classes of sulfated GAGs, heparan sulfate and chondroitin/dermatan sulfate, using liquid chromatography, mass spectrometry, and radiolabeling techniques. Overall, these methods facilitate the evaluation of GAG structure and function to uncover the unique roles these molecules play in cell biology and human disease.


Assuntos
Glicosaminoglicanos , Heparitina Sulfato , Humanos , Animais , Glicosaminoglicanos/química , Heparitina Sulfato/análise , Heparitina Sulfato/química , Sulfatos de Condroitina/química , Cromatografia Líquida , Ácidos Urônicos , Sulfatos
9.
J Environ Sci (China) ; 125: 26-36, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36375912

RESUMO

Herein, a one-step co-pyrolysis protocol was adopted for the first time to prepare a novel pyrogenic carbon-Cu0/Fe3O4 heteroatoms (FCBC) in CO2 ambiance to discern the roles of each component in PDS activation. During co-pyrolysis, CO2 catalyzed formation of reducing gases by biomass which facilitated reductive transformation of Fe3+ and Cu2+ to Cu0 and Fe3O4, respectively. According to the analysis, the resulting metal (oxide) catalyzed graphitization of biocharand decomposition of volatile substances resulting in an unprecedented surface area (1240 m2/g). The resulting FCBC showed greater structural defects and less electrical impedance. Batch experiments indicated that Rhodamine B (RhB) degradation by FCBC (100%) was superior to Fe3O4 (50%) and Cu0/Fe3O4 (76.4%) in persulfate (PDS) system, which maintained reasonable efficiency (75.6%-63.6%) within three cycles. The reactive oxygen species (ROS) associated with RhB degradation was identified by an electron paramagnetic resonance and confirmed by scavenging experiments. RhB degradation invoked both (sulfate and dominantly hydroxyl) radical and non-radical (singlet oxygen, 1O2) pathways. Regarding FCBC, Cu0 can continuously react with Fe3+ in Fe3O4 to generate larger quantities of Fe2+, and both Cu0 and Fe2+ activated PDS to yield sulfate radicals which was quickly converted to hydroxyl radical. Besides, Cu0/Cu2+ could complex with PDS to form a metastable complex, which particularly contributed to 1O2 generation. These cascade reactions by FCBC were reinforced by carbonyl group of biochar and favorable electron transfer ability. This work highlighted a new approach to prepare a magnetic and environment-benign heterogonous catalyst to remove organic pollutants in water.


Assuntos
Grafite , Pirólise , Dióxido de Carbono , Carvão Vegetal/química , Sulfatos/química , Radical Hidroxila
10.
J Environ Sci (China) ; 125: 61-72, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36375943

RESUMO

Clarifying the role of sulfate and dissolved oxygen (DO) in methane production may allow for precise and accurate modeling of methane emissions in eutrophic lakes. We conducted field observations of sulfate, methane, and DO concentrations in Lake Abashiri, a typical brackish and eutrophic lake in a cold region, to develop a DO-based method for quantitively estimating methane production in a eutrophic lake and analyzed the results. We found that sulfate concentrations decreased rapidly from 900.0 mg/L in water overlying the sediments to nearly 0.0 mg/L in the bottom sediment. Methane production was almost uniform across sediment depths of 0.05 to 0.25 m, ranging from 1400 to 1800 µmol/m2/day. Also, methane production was found to be a function of DO concentrations in water overlying the bottom and could be modeled by a logistic function: constant production at 1,400 µmol/m2/day for DO concentrations of 0.0 to 3.0 mg/L, rapidly decreasing to 0 µmol/m2/day for DO concentrations of 3.0 to 6.0 mg/L. This methane model was verified using a simple one-dimensional numerical model that showed good agreement with field observations. Our results thus suggest that the proposed methane model reduces uncertainty in estimating methane production in a eutrophic lake.


Assuntos
Lagos , Oxigênio , Metano , Sulfatos , Água , Sedimentos Geológicos
11.
J Environ Sci (China) ; 125: 712-722, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36375952

RESUMO

The sulfur-containing odor emitted from sludge composting could be controlled by sulfide oxidizing bacteria, yet mesophilic strains show inactivation during the thermophilic stage of composting. Aimed to investigate and characterize the thermotolerant bacterium that could oxidize sulfide into sulfate, a heterotrophic strain was isolated from sewage sludge composting and identified as Paenibacillus naphthalenovorans LYH-3. The effects of various environmental factors on sulfide oxidation capacities were studied to optimize the sulfate production, and the highest production rate (27.35% ± 0.86%) was obtained at pH 7.34, the rotation speed of 161.14 r/min, and the inoculation amount of 5.83% by employing Box-Behnken design. The results of serial sulfide substrates experiments indicated that strain LYH-3 could survive up to 400 mg/L of sulfide with the highest sulfide removal rate (88.79% ± 0.35%) obtained at 50 mg/L of sulfide. Growth kinetic analysis presented the maximum specific growth rate µm (0.5274 hr-1) after 22 hr cultivation at 50°C. The highest enzyme activities of sulfide quinone oxidoreductase (0.369 ± 0.052 U/mg) and sulfur dioxygenase (0.255 ± 0.014 U/mg) were both obtained at 40°C, and the highest enzyme activity of sulfite acceptor oxidoreductase (1.302 ± 0.035 U/mg) was assessed at 50°C. The results indicated that P. naphthalenovorans possessed a rapid growth rate and efficient sulfide oxidation capacities under thermophilic conditions, promising a potential application in controlling sulfur-containing odors during the thermophilic stage of sludge composting.


Assuntos
Compostagem , Paenibacillus , Esgotos/química , Sulfatos , Cinética , Sulfetos , Óxidos de Enxofre , Oxirredutases , Enxofre
12.
J Environ Sci (China) ; 125: 786-797, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36375960

RESUMO

Microbial electrosynthesis system (MES) is a promising method that can use carbon dioxide, which is a greenhouse gas, to produce methane which acts as an energy source, without using organic substances. However, this bioelectrical reduction reaction can proceed at a certain high applied voltage when coupled with water oxidation in the anode coated with metallic catalyst. When coupled with the oxidation of HS- to SO42-, methane production is thermodynamically more feasible, thus implying its production at a considerably lower applied voltage. In this study, we demonstrated the possibility of electrotrophic methane production coupled with HS- oxidation in a cost-effective bioanode chamber in the MES without organic substrates at a low applied voltage of 0.2 V. In addition, microbial community analyses of biomass enriched in the bioanode and biocathode were used to reveal the most probable pathway for methane production from HS- oxidation. In the bioanode, electroautotrophic SO42- production accompanied with electron donation to the electrode is performed mainly by the following two steps: first, incomplete sulfide oxidation to sulfur cycle intermediates (SCI) is performed; then the produced SCI are disproportionated to HS- and SO42-. In the biocathode, methane is produced mainly via H2 and acetate by electron-accepting syntrophic bacteria, homoacetogens, and acetoclastic archaea. Here, a new eco-friendly MES with biological H2S removal is established.


Assuntos
Dióxido de Carbono , Sulfatos , Dióxido de Carbono/química , Sulfatos/metabolismo , Metano/metabolismo , Eletrodos , Sulfetos/química , Oxirredução , Óxidos de Enxofre
13.
Chemosphere ; 310: 136731, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36209855

RESUMO

Multiple stage anaerobic system was found to be an effective strategy for reductive decolorization of azo dyes in the presence of sulfate. Bulk color removal (56-90%) was achieved concomitant with acidogenic activity in the 1st-stage reactor (R1), while organic matter removal (≤100%) and sulfate reduction (≤100%) occurred predominantly in the 2nd-stage reactor (R2). However, azo dye reduction mechanism and metabolic routes involved remain unclear. The involved microbial communities and conditions affecting the azo dye removal in a two-stage anaerobic digestion (AD) system were elucidated using amplicon sequencing (16S rRNA, fhs, dsrB and mcrA) and correlation analysis. Reductive decolorization was found to be co-metabolic and mainly associated with hydrogen-producing pathways. We also found evidence of the involvement of an azoreductase from Lactococcus lactis. Bacterial community in R1 was sensitive and shifted in the presence of the azo dye, while microorganisms in R2 were more protected. Higher diversity of syntrophic-acetate oxidizers, sulfate reducers and methanogens in R2 highlights the role of the 2nd-stage in organic matter and sulfate removals, and these communities might be involved in further transformations of the azo dye reduction products. The results improve our understanding on the role of different microbial communities in anaerobic treatment of azo dyes and can help in the design of better solutions for the treatment of textile effluents.


Assuntos
Compostos Azo , Microbiota , Compostos Azo/metabolismo , Reatores Biológicos/microbiologia , RNA Ribossômico 16S/genética , RNA Ribossômico 16S/metabolismo , Corantes/metabolismo , Sulfatos , Redes e Vias Metabólicas
14.
Chemosphere ; 310: 136747, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36216113

RESUMO

Dissolved heavy metals (DHMs) contamination has raised global concern for ecological and human health development. Weathering of sulfide-bearing ore metals can produce acidic, sulfate-rich solutions in the presence of water and oxygen (O2), and DHMs are released to deprave the river water quality. Sulfur and oxygen isotope signatures (δ34SSO4 and δ18OSO4) could identify this pyrite-derived sulfate; however, it is yet not well known whether the δ34SSO4 and δ18OSO4 values could limit the DHMs sources and illustrate anthropogenic impacts on DHMs along the river corridor. We tried to solve this problem through field works in the Luohe River and Yihe River, two tributaries of the Yellow River, China, where metal sulfide mine activities mostly occurred upstream, but agricultural and domestic behaviors concentrated in the lower plain reaches. In the Luohe River upper areas, δ34SSO4 values had negative correlations with concentrations of cadmium (Cd) (p < 0.01), nickel (Ni) (p < 0.05), molybdenum (Mo) (p < 0.01), uranium (U) (p < 0.01), and SO42- (p < 0.01). However, as the δ34SSO4 values increased downstream in the Luohe River, concentrations of copper (Cu) (p < 0.05), mercury (Hg) (p < 0.05), Ni (p < 0.05), and SO42- (p < 0.01) simultaneously elevated. The Bayesian Isotope Mixing Model (BIMM) results via δ34SSO4 values demonstrated 64.3%-65.3% of SO42- from acid mine drainage (AMD) in the Luohe River's upper reaches and 63.5%-67.7% in the Yihe River's upper reaches, and about 33% from sewage and industrial effluents in the Luohe River's lower reaches and 27% in Yihe River's lower reaches. Our results confirmed the different anthropogenic impacts on the DHMs concentrations in Luohe River and Yihe River and provided a robust method for DHMs sources appointment and pollution management in river systems.


Assuntos
Mercúrio , Metais Pesados , Poluentes Químicos da Água , Humanos , Monitoramento Ambiental/métodos , Poluentes Químicos da Água/análise , Teorema de Bayes , Efeitos Antropogênicos , Metais Pesados/análise , Sulfatos/análise , Isótopos de Oxigênio/análise , Sulfetos , China
15.
Chemosphere ; 310: 136915, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36270520

RESUMO

In this work, zero-valent iron (ZVI) combined with anaerobic bacteria was used in the remediation of Cd(II)-polluted soil under the mediation of sulfate (SO42-). Owing to hydrogen-autotrophic sulfate reduction, serious corrosion occurred on sulfate-mediated biotic ZVI in terms of solid phase characterization as massive corrosive products (e.g., goethite, magnetite and green rust) were formed, which were crucial in the immobilization of Cd(II). Thus, this integrated system achieved a 4.9-fold increase in aqueous Cd(II) removal and converted more than 53% of easily available Cd(II)-fractions (acid-extractable and reducible) to stable forms (oxidizable and residual) based on the sequential extraction results as compared to the sulfate-mediated ZVI system. Increasing SO42- concentration and ZVI dosage both demonstrated positive correlation to Cd(II) immobilization, which further reflected that hydrogenotrophic desulfuration acted an essential role in improving Cd(II) immobilization. It indicated that hydrogenotrophic desulfuration could accelerate iron corrosion and promote reactive mineral formation through biomineralization, as well as generate cadmium sulfide precipitates (CdS) to achieve excellent immobilization performance for Cd(II). Besides, this reaction was favorable under neutral pH condition. Our results highlighted the promoted effect of hydrogen-autotrophic desulfuration on ZVI corrosion to immobilize Cd(II) and offered a practicable technique in Cd(II)-polluted soil remediation.


Assuntos
Ferro , Solo , Ferro/química , Sulfatos , Cádmio/análise , Hidrogênio
16.
Sci Total Environ ; 856(Pt 1): 158839, 2023 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-36155030

RESUMO

Bio-cathode Microbial electrolysis cell (MEC) has been widely discovered for heavy metals removal and hydrogen production. However, low electron transfer efficiency and heavy metal toxicity limit MEC treatment efficiency. In this study, ZIF-67 was introduced to modify Sulfate-reducing bacteria (SRB) bio-cathode to enhance the bioreduction of sulfate and Antimony (Sb) with hydrogen production in the MEC. ZIF-67 modified bio-cathode was developed from a bio-anode microbial fuel cell (MFC) by operating with an applied voltage of 0.8 V to reverse the polarity. Cyclic voltammetry, linear sweep voltammetry and electrochemical impedance were done to confirm the performance of the ZIF-67 modified SRB bio-cathode. The synergy reduction of sulfate and Sb was accomplished by sulfide metal precipitation reaction from SRB itself. Maximum sulfate reduction rate approached 93.37 % and Sb removal efficiency could reach 92 %, which relies on the amount of sulfide concentration generated by sulfate reduction reaction, with 0.923 ± 0.04 m3 H2/m3 of hydrogen before adding Sb and 0.857 m3 H2/m3 of hydrogen after adding Sb. The hydrogen was mainly produced in this system and the result of gas chromatography (GC) indicated that 73.27 % of hydrogen was produced. Meanwhile the precipitates were analyzed by X-ray diffraction and X-ray photoelectron spectroscopy to confirm Sb2S3 was generated from Sb (V).


Assuntos
Fontes de Energia Bioelétrica , Desulfovibrio , Metais Pesados , Eletrólise/métodos , Eletrodos , Fontes de Energia Bioelétrica/microbiologia , Sulfatos/química , Hidrogênio/química , Sulfetos/química
17.
Sci Total Environ ; 856(Pt 1): 158980, 2023 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-36174687

RESUMO

Membrane Aerated Biofilm Reactors (MABR) are gaining more and more acceptance in the plethora of wastewater process intensification technologies. Mathematical modelling has contributed to show their feasibility in terms of reduced energy consumption and footprint. Nevertheless, most simulation studies published until now are still focused on analyzing MABR as single units and not fully integrated within the flow diagram of the water treatment plant (WWTP). In this paper, the prediction capabilities of an integrated modelling approach is tested using full-scale data from Ejby Mølle WWTP+MABR site (Odense, Denmark). Mass balances, data reconciliation methods, process simulation and the different evaluation criteria were used to adjust influent, effluent and process indicators. Results show 10 % mismatch between flow, COD, N and P predictions and measurements in different plant locations. Using the adopted hydraulic retention time (HRT), nitrogen load (NL), membrane surface area (MA) and oxygen transfer rate (OTR), it was possible to predict nitrification rates (NR) within the interquartile range. This has been done under two different MABR operational conditions: with (#S2) and without (#S1) external aeration (EA) in the bulk liquid. The model provides additional process insights about biofilm structure, substrate gradients, weak acid base chemistry and precipitation potential. More specifically, simulations suggest the potential undesirable effects of sulfate (SRB) and iron reducing bacteria (IRB) on both microbial activity and composition of the biofilm. The latter may have a strong impact on ammonium (NHx), sulfate (SOx) and ferrous ion (Fe+2) conversion processes. The change of operational strategy in the scenario analysis highlights that the denitrifying activity of phosphorus accumulating organisms (PAOs) can enhance nutrient removal in MABR tanks. In addition, it was possible to assess the chance of success (in terms of energetic cost of nitrogen removal) of adding several MABR units in one tank of the WWTP under study before full-scale implementation.


Assuntos
Biofilmes , Reatores Biológicos , Reatores Biológicos/microbiologia , Águas Residuárias/química , Nitrificação , Nitrogênio , Sulfatos , Eliminação de Resíduos Líquidos/métodos
18.
Sci Total Environ ; 856(Pt 1): 159115, 2023 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-36181827

RESUMO

Microorganisms developed a mechanism that copes with heat, acidity, and high dissolved metal concentrations that likely first evolved. The geothermal fluids emerging in the geothermal springs of Taiwan, located at a subduction zone, are still under signs of progress in the characterization of the various microbial taxonomic changes over time. However, no systematic studies have been performed to compare water, biofilms, and sediment bacterial communities and the primary driving force of dissolved and mineral substrates capable of supporting microbial metabolism. In this study, 16S rRNA gene sequencing was employed for bacterial community exploration, and their potential metabolic pathways involved from water, biofilms, and sediment samples, collected from the geothermal valley (Ti-re-ku). Metagenomic data revealed that the water samples had higher bacterial diversity and richness than biofilms and sediment samples. At the genus level, Alicyclobacillus, Thiomonas, Acidocella, Metallibacterium, Picrophilus, and Legionella were significantly abundant in the water samples. The biofilms were rich in Aciditerrimonas, Bacillus, Acidithiobacillus, and Lysinibacillus, whereas the sediment samples were abundant in Sulfobacillus. The PICRUSt2-predicted functional results revealed that heavy metal-related functions such as heavy-metal exporter system, cobalt­zinc­cadmium resistance, arsenical pump, high-affinity nickel-transport, and copper resistance metabolisms were significant in the water samples. Moreover, sulfur-related pathways such as thiosulfate oxidation, dissimilatory sulfate reduction, and assimilatory sulfate reduction were important in water samples, followed by biofilms and sediment. Therefore, our findings highlighted the comparative taxonomic diversity and functional composition contributions to geothermal fluid, with implications for understanding the evolution and ecological niche dimension of microbes which are the key to geothermal ecosystem function.


Assuntos
Fontes Termais , Metais Pesados , Fontes Termais/microbiologia , Ecossistema , RNA Ribossômico 16S/genética , Água/química , Taiwan , Bactérias/genética , Biofilmes , Sulfatos
19.
Sci Total Environ ; 856(Pt 2): 159142, 2023 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-36183767

RESUMO

Acid sulfate soils discharge large amounts of sulfuric acid along with toxic metals, deteriorating water quality and ecosystem health of recipient waterbodies. There is thus an urgent need to develop cost-effective and sustainable measures to mitigate the negative effects of these soils. In this study, we flushed aseptically-prepared MQ water (reference) or mitigation suspensions containing calcite, peat or a combination of both through 15-cm-thick soil cores from an acid sulfate soil field in western Finland, and investigated the geochemistry of Fe and S on the surfaces of macropores and in the solid columnar blocks (interiors) of the soil columns. The macropore surfaces of all soil columns were strongly enriched in total and HCl-extractable Fe and S relative to the interiors, owing to the existence of abundant Fe oxyhydroxysulfates (schwertmannite and partly jarosite) as yellow-to-brownish surface-coatings. The dissolution/hydrolysis of Fe oxyhydroxysulfates (predominantly jarosite) on the macropore surfaces of the reference columns, although being constantly flushed, effectively buffered the permeates at pH close to 4. These results suggest that Fe oxyhydroxysulfates accumulated on the macropore surfaces of boreal acid sulfate soils can act as long-lasting acidification sources. The treatments with mitigation suspensions led to a (near-)complete conversion of jarosite to Fe hydroxides, causing a substantial loss of S. In contrast, we did not observe any recognizable evidence indicating transformation of schwertmannite. However, sulfate sorbed by this mineral might be partially lost through anion-exchange processes during the treatments with calcite. No Fe sulfides were found in the peat-treated columns. Since Fe sulfides can support renewed acidification events, the moderate mineralogical changes induced by peat are desirable. In addition, peat materials can act as toxic-metal scavengers. Thus, the peat materials used here, which is relatively cheap in the boreal zone, is ideal for remediating boreal acid sulfate soils and other similar jarosite-bearing soils.


Assuntos
Ferro , Solo , Ferro/análise , Carbonato de Cálcio , Ecossistema , Sulfatos , Enxofre , Ácidos , Sulfetos
20.
Sci Total Environ ; 856(Pt 1): 159173, 2023 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-36191721

RESUMO

Studies of the land-sea-air interactions of aerosol are scarce considering their significant role in global environmental changes. Here, we investigated potential sources of sub-micron aerosols over the East Sea (Sea of Japan), which is strongly influenced by continental and marine aerosols. A high-resolution time-of-flight aerosol mass spectrometer (HR-ToF-AMS) was used to measure the size-resolved chemical compositions of sub-micron aerosols during the period March 10-15, 2020. Concentrations of all AMS species, black carbon (BC), PM10 (particulate matter <10 µm) and PM2.5 (particulate matter <2.5 µm) were higher when cruising in industrialized coastal areas compared to the offshore region. A positive matrix factorization (PMF) model identified five distinct sources, i.e., hydrocarbon-like organic aerosol, semi-volatile and low-volatile oxygenated aerosols, methanesulfonic acid (MSA), and dimethyl sulfide (DMS; C2H6S) oxidation, which accounted for 5.98 %, 21.6 %, 28.3 %, 34.5 %, and 9.64 % of the total organic mass, respectively. The spatiotemporal variation of MSA, as well as the MSA to sulfate ratio (MSA:SO42-) over the East Sea, was determined for the first time. The mass concentrations of MSA displayed a similar time series distribution pattern to those of DMS. The time series distributions of the MSA:SO42- ratio displayed distinct differences, with higher ratios downwind of the ocean (0.216 ± 0.083 µg·m-3) than land (0.089 ± 0.030 µg·m-3). The growth of ultrafine particles (10-35 nm) was observed during two of the elevated MSA:SO42- ratio events, suggesting a potential role of MSA in new particle formation.


Assuntos
Poluentes Atmosféricos , Poluentes Atmosféricos/análise , Japão , Aerossóis/análise , Material Particulado/análise , Sulfatos
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