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1.
Geobiology ; 22(3): e12600, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38725144

RESUMO

Microbial sulfate reduction is central to the global carbon cycle and the redox evolution of Earth's surface. Tracking the activity of sulfate reducing microorganisms over space and time relies on a nuanced understanding of stable sulfur isotope fractionation in the context of the biochemical machinery of the metabolism. Here, we link the magnitude of stable sulfur isotopic fractionation to proteomic and metabolite profiles under different cellular energetic regimes. When energy availability is limited, cell-specific sulfate respiration rates and net sulfur isotope fractionation inversely covary. Beyond net S isotope fractionation values, we also quantified shifts in protein expression, abundances and isotopic composition of intracellular S metabolites, and lipid structures and lipid/water H isotope fractionation values. These coupled approaches reveal which protein abundances shift directly as a function of energy flux, those that vary minimally, and those that may vary independent of energy flux and likely do not contribute to shifts in S-isotope fractionation. By coupling the bulk S-isotope observations with quantitative proteomics, we provide novel constraints for metabolic isotope models. Together, these results lay the foundation for more predictive metabolic fractionation models, alongside interpretations of environmental sulfur and sulfate reducer lipid-H isotope data.


Assuntos
Desulfovibrio vulgaris , Proteômica , Isótopos de Enxofre , Isótopos de Enxofre/análise , Isótopos de Enxofre/metabolismo , Desulfovibrio vulgaris/metabolismo , Proteoma/metabolismo , Proteoma/análise , Metabolismo Energético , Metaboloma , Proteínas de Bactérias/metabolismo , Oxirredução , Sulfatos/metabolismo
2.
Environ Microbiol ; 26(5): e16628, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38757470

RESUMO

The degradation of freshwater systems by salt pollution is a threat to global freshwater resources. Salinization is commonly identified by increased specific conductance (conductivity), a proxy for salt concentrations. However, conductivity fails to account for the diversity of salts entering freshwaters and the potential implications this has on microbial communities and functions. We tested 4 types of salt pollution-MgCl2, MgSO4, NaCl, and Na2SO4-on bacterial taxonomic and functional α-, ß-diversity of communities originating from streams in two distinct localities (Nebraska [NE] and Ohio [OH], USA). Community responses depended on the site of origin, with NE and OH exhibiting more pronounced decreases in community diversity in response to Na2SO4 and MgCl2 than other salt amendments. A closer examination of taxonomic and functional diversity metrics suggests that core features of communities are more resistant to induced salt stress and that marginal features at both a population and functional level are more likely to exhibit significant structural shifts based on salt specificity. The lack of uniformity in community response highlights the need to consider the compositional complexities of salinization to accurately identify the ecological consequences of instances of salt pollution.


Assuntos
Bactérias , Água Doce , Microbiota , Salinidade , Cloreto de Sódio , Água Doce/microbiologia , Bactérias/efeitos dos fármacos , Bactérias/classificação , Bactérias/genética , Microbiota/efeitos dos fármacos , Ohio , Sulfatos/metabolismo , Biodiversidade , Sulfato de Magnésio/farmacologia , Cloreto de Magnésio/farmacologia
3.
Carbohydr Polym ; 337: 122157, 2024 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-38710573

RESUMO

Seaweed polysaccharides, particularly sulfated ones, exhibited potent antiviral activity against a wide variety of enveloped viruses, such as herpes simplex virus and respiratory viruses. Different mechanisms of action were suggested, which may range from preventing infection to intracellular antiviral activity, at different stages of the viral cycle. Herein, we generated two chemically engineered sulfated fucans (C303 and C304) from Cystoseira indica by an amalgamated extraction-sulfation procedure using chlorosulfonic acid-pyridine/N,N-dimethylformamide and sulfur trioxide-pyridine/N,N-dimethylformamide reagents, respectively. These compounds exhibited activity against HSV-1 and RSV with 50 % inhibitory concentration values in the range of 0.75-2.5 µg/mL and low cytotoxicity at concentrations up to 500 µg/mL. The antiviral activities of chemically sulfated fucans (C303 and C304) were higher than the water (C301) and CaCl2 extracted (C302) polysaccharides. Compound C303 had a (1,3)-linked fucan backbone and was branched. Sulfates were present at positions C-2, C-4, and C-2,4 of Fucp, and C-6 of Galp residues of this polymer. Compound C304 had a comparable structure but with more sulfates at C-4 of Fucp residue. Both C303 and C304 were potent antiviral candidates, acting in a dose-dependent manner on the adsorption and other intracellular stages of HSV-1 and RSV replication, in vitro.


Assuntos
Antivirais , Herpesvirus Humano 1 , Polissacarídeos , Antivirais/farmacologia , Antivirais/química , Chlorocebus aethiops , Herpesvirus Humano 1/efeitos dos fármacos , Polissacarídeos/farmacologia , Polissacarídeos/química , Polissacarídeos/isolamento & purificação , Animais , Células Vero , Humanos , Sulfatos/química , Sulfatos/farmacologia , Vírus Sinciciais Respiratórios/efeitos dos fármacos
4.
Org Biomol Chem ; 22(19): 3986-3994, 2024 05 15.
Artigo em Inglês | MEDLINE | ID: mdl-38695061

RESUMO

Algae-based marine carbohydrate drugs are typically decorated with negative ion groups such as carboxylate and sulfate groups. However, the precise synthesis of highly sulfated alginates is challenging, thus impeding their structure-activity relationship studies. Herein we achieve a microwave-assisted synthesis of a range of highly sulfated mannuronate glycans with up to 17 sulfation sites by overcoming the incomplete sulfation due to the electrostatic repulsion of crowded polyanionic groups. Although the partially sulfated tetrasaccharide had the highest affinity for the receptor binding domain (RBD) of the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) Omicron variant, the fully sulfated octasaccharide showed the most potent interference with the binding of the RBD to angiotensin-converting enzyme 2 (ACE2) and Vero E6 cells, indicating that the sulfated oligosaccharides might inhibit the RBD binding to ACE2 in a length-dependent manner.


Assuntos
Enzima de Conversão de Angiotensina 2 , Antivirais , Micro-Ondas , Polissacarídeos , SARS-CoV-2 , SARS-CoV-2/efeitos dos fármacos , Antivirais/farmacologia , Antivirais/síntese química , Antivirais/química , Chlorocebus aethiops , Enzima de Conversão de Angiotensina 2/metabolismo , Enzima de Conversão de Angiotensina 2/antagonistas & inibidores , Enzima de Conversão de Angiotensina 2/química , Células Vero , Polissacarídeos/química , Polissacarídeos/farmacologia , Polissacarídeos/síntese química , Humanos , Animais , Glicoproteína da Espícula de Coronavírus/antagonistas & inibidores , Glicoproteína da Espícula de Coronavírus/metabolismo , Glicoproteína da Espícula de Coronavírus/química , Ácidos Hexurônicos/química , Ácidos Hexurônicos/farmacologia , Ácidos Hexurônicos/síntese química , Sulfatos/química , Sulfatos/farmacologia , Sulfatos/síntese química , Tratamento Farmacológico da COVID-19 , Relação Estrutura-Atividade
5.
Environ Microbiol Rep ; 16(3): e13263, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38705733

RESUMO

Deep-sea methane seeps are amongst the most biologically productive environments on Earth and are often characterised by stable, low oxygen concentrations and microbial communities that couple the anaerobic oxidation of methane to sulfate reduction or iron reduction in the underlying sediment. At these sites, ferrous iron (Fe2+) can be produced by organoclastic iron reduction, methanotrophic-coupled iron reduction, or through the abiotic reduction by sulfide produced by the abundant sulfate-reducing bacteria at these sites. The prevalence of Fe2+in the anoxic sediments, as well as the availability of oxygen in the overlying water, suggests that seeps could also harbour communities of iron-oxidising microbes. However, it is unclear to what extent Fe2+ remains bioavailable and in solution given that the abiotic reaction between sulfide and ferrous iron is often assumed to scavenge all ferrous iron as insoluble iron sulfides and pyrite. Accordingly, we searched the sea floor at methane seeps along the Cascadia Margin for microaerobic, neutrophilic iron-oxidising bacteria, operating under the reasoning that if iron-oxidising bacteria could be isolated from these environments, it could indicate that porewater Fe2+ can persist is long enough for biology to outcompete pyritisation. We found that the presence of sulfate in our enrichment media muted any obvious microbially-driven iron oxidation with most iron being precipitated as iron sulfides. Transfer of enrichment cultures to sulfate-depleted media led to dynamic iron redox cycling relative to abiotic controls and sulfate-containing cultures, and demonstrated the capacity for biogenic iron (oxyhydr)oxides from a methane seep-derived community. 16S rRNA analyses revealed that removing sulfate drastically reduced the diversity of enrichment cultures and caused a general shift from a Gammaproteobacteria-domainated ecosystem to one dominated by Rhodobacteraceae (Alphaproteobacteria). Our data suggest that, in most cases, sulfur cycling may restrict the biological "ferrous wheel" in contemporary environments through a combination of the sulfur-adapted sediment-dwelling ecosystems and the abiotic reactions they influence.


Assuntos
Bactérias , Sedimentos Geológicos , Ferro , Metano , Oxirredução , Enxofre , Metano/metabolismo , Ferro/metabolismo , Enxofre/metabolismo , Sedimentos Geológicos/microbiologia , Sedimentos Geológicos/química , Bactérias/metabolismo , Bactérias/genética , Bactérias/classificação , Água do Mar/microbiologia , Água do Mar/química , Sulfetos/metabolismo , Sulfatos/metabolismo , RNA Ribossômico 16S/genética , Filogenia
6.
Sci Total Environ ; 931: 172898, 2024 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-38697543

RESUMO

The production of short-chain fatty acids (SCFAs) is constrained by substrate availability and the increased fractional pressure of H2 emitted by acidogenic/fermentative bacteria during anaerobic fermentation of waste activated sludge (WAS). This study introduced a novel approach employing zero-valent iron (ZVI)-activated sulfite pretreatment combined with H2-consuming sulfate-reducing bacteria (SRB) mediation to improve SCFAs, especially acetate production from WAS fermentation. Experimental results showed that the combined ZVI-activated sulfite and incomplete-oxidative SRB (io-SRB) process achieved a peak SCFAs production of 868.11 mg COD/L, with acetate accounting for 80.55 %, which was 7.90- and 2.18-fold higher than that obtained from raw WAS fermentation, respectively. This could be firstly attributed to the SO4- and OH generated by ZVI-activated sulfite, which significantly promoted WAS decomposition, e.g., soluble proteins and carbohydrates increased 14.3- and 10.8-fold, respectively, over those in raw WAS. The biodegradation of dissolved organic matter was subsequently enhanced by the synergistic interaction and H2 transfer between anaerobic fermentation bacteria (AFB) and io-SRB. The positive and negative correlations among AFB, nitrate-reducing bacteria (NRB) and the io-SRB consortia were revealed by molecular ecological network (MEN) and Mantel test. Moreover, the expression of functional genes was also improved, for instance, in relation to acetate formation, the relative abundances of phosphate acetyltransferase and acetate kinase was 0.002 % and 0.005 % higher than that in the control test, respectively. These findings emphasized the importance of sulfate radicals-based oxidation pretreatment and the collaborative relationships of multifunctional microbes on the value-added chemicals and energy recovery from sludge fermentation.


Assuntos
Ácidos Graxos Voláteis , Fermentação , Esgotos , Sulfitos , Eliminação de Resíduos Líquidos , Esgotos/microbiologia , Sulfitos/metabolismo , Ácidos Graxos Voláteis/metabolismo , Eliminação de Resíduos Líquidos/métodos , Sulfatos/metabolismo , Hidrogênio/metabolismo , Bactérias/metabolismo , Ferro/metabolismo
7.
Sci Total Environ ; 931: 172846, 2024 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-38703858

RESUMO

The development of low-cost, highly efficient adsorbent materials is of significant importance for environmental remediation. In this study, a novel material, sulfurized nano zero-valent iron loaded biomass carbon (S-nZVI/BC), was successfully synthesized by a simple manufacturing process. The preparation of S-nZVI/BC does not require the use of expensive and hazardous chemicals. Instead, residual sludge, a solid waste product, is used as feedstock. The sludge is rich in Sulfate-Reducing Bacteria (SRB), which can provide carbon and sulfur sources for the synthesis of S-nZVI/BC. It was observed that S-nZVI particles formed in situ were dispersed within BC and covered by it. Additionally, S-nZVI/BC inherited the large specific surface area and porosity of BC. The adsorption capacity of S-nZVI/BC can reach 857.55 mg g-1 Hg (II) during the remediation of mercury-polluted water. This research offers new perspectives for developing composites in terms of the low cost and harmlessness of raw materials.


Assuntos
Biomassa , Ferro , Mercúrio , Poluentes Químicos da Água , Ferro/química , Poluentes Químicos da Água/análise , Adsorção , Enxofre/química , Recuperação e Remediação Ambiental/métodos , Bactérias Redutoras de Enxofre/metabolismo , Sulfatos/química
8.
Environ Sci Technol ; 58(20): 8966-8975, 2024 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-38722667

RESUMO

The absolute radical quantum yield (Φ) is a critical parameter to evaluate the efficiency of radical-based processes in engineered water treatment. However, measuring Φ is fraught with challenges, as current quantification methods lack selectivity, specificity, and anti-interference capabilities, resulting in significant error propagation. Herein, we report a direct and reliable time-resolved technique to determine Φ at pH 7.0 for commonly used radical precursors in advanced oxidation processes. For H2O2 and peroxydisulfate (PDS), the values of Φ•OH and ΦSO4•- at 266 nm were measured to be 1.10 ± 0.01 and 1.46 ± 0.05, respectively. For peroxymonosulfate (PMS), we developed a new approach to determine Φ•OHPMS with terephthalic acid as a trap-and-trigger probe in the nonsteady state system. For the first time, the Φ•OHPMS value was measured to be 0.56 by the direct method, which is stoichiometrically equal to ΦSO4•-PMS (0.57 ± 0.02). Additionally, radical formation mechanisms were elucidated by density functional theory (DFT) calculations. The theoretical results showed that the highest occupied molecular orbitals of the radical precursors are O-O antibonding orbitals, facilitating the destabilization of the peroxy bond for radical formation. Electronic structures of these precursors were compared, aiming to rationalize the tendency of the Φ values we observed. Overall, this time-resolved technique with specific probes can be used as a reliable tool to determine Φ, serving as a scientific basis for the accurate performance evaluation of diverse radical-based treatment processes.


Assuntos
Radical Hidroxila , Sulfatos , Sulfatos/química , Radical Hidroxila/química , Purificação da Água/métodos , Oxirredução , Peróxido de Hidrogênio/química
9.
J Plant Physiol ; 297: 154260, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38701679

RESUMO

Sulfur is an essential nutrient for all plants, but also crucial for the nitrogen fixing symbiosis between legumes and rhizobia. Sulfur limitation can hamper nodule development and functioning. Until now, it remained unclear whether sulfate uptake into nodules is local or mainly systemic via the roots, and if long-distance transport from shoots to roots and into nodules occurs. Therefore, this work investigates the systemic regulation of sulfur transportation in the model legume Lotus japonicus by applying stable isotope labeling to a split-root system. Metabolite and protein extraction together with mass spectrometry analyses were conducted to determine the plants molecular phenotype and relative isotope protein abundances. Data show that treatments of varying sulfate concentrations including the absence of sulfate on one side of a nodulated root was not affecting nodule development as long as the other side of the root system was provided with sufficient sulfate. Concentrations of shoot metabolites did not indicate a significant stress response caused by a lack of sulfur. Further, we did not observe any quantitative changes in proteins involved in biological nitrogen fixation in response to the different sulfate treatments. Relative isotope abundance of 34S confirmed a long-distance transport of sulfur from one side of the roots to the other side and into the nodules. Altogether, these results provide evidence for a systemic long-distance transport of sulfur via the upper part of the plant to the nodules suggesting a demand driven sulfur distribution for the maintenance of symbiotic N-fixation.


Assuntos
Lotus , Proteínas de Plantas , Nódulos Radiculares de Plantas , Enxofre , Simbiose , Nódulos Radiculares de Plantas/metabolismo , Enxofre/metabolismo , Proteínas de Plantas/metabolismo , Lotus/metabolismo , Transporte Biológico , Fixação de Nitrogênio , Sulfatos/metabolismo , Raízes de Plantas/metabolismo
10.
Bioprocess Biosyst Eng ; 47(6): 943-955, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38703203

RESUMO

At present, the application of sewage treatment technologies is restricted by high sulfate concentrations. In the present work, the sulfate removal was biologically treated using an upflow anaerobic sludge blanket (UASB) in the absence/presence of light. First, the start-up of UASB for the sulfate removal was studied in terms of COD degradation, sulfate removal, and effluent pH. Second, the impacts of different operation parameters (i.e., COD/SO42- ratio, temperature and illumination time) on the UASB performance were explored. Third, the properties of sludge derived from the UASB at different time were analyzed. Results show that after 28 days of start-up, the COD removal efficiencies in both the photoreactor and non-photoreactor could reach a range of 85-90% while such reactors could achieve > 90% of sulfate being removed. Besides, higher illumination time could facilitate the removal of pollutants in the photoreactor. To sum up, the present study can provide technical support for the clean removal of sulfate from wastewater using photoreactors.


Assuntos
Luz , Esgotos , Sulfatos , Sulfatos/química , Esgotos/microbiologia , Reatores Biológicos , Anaerobiose , Águas Residuárias/química , Eliminação de Resíduos Líquidos/métodos , Poluentes Químicos da Água/isolamento & purificação , Poluentes Químicos da Água/química , Purificação da Água/métodos
11.
Mar Drugs ; 22(5)2024 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-38786622

RESUMO

Five new sulfated arylpyrrole and arylpyrrolone alkaloids, denigrins H-L (1-5), along with two known compounds, dictyodendrin B and denigrin G, were isolated from an extract of a New Zealand Dictyodendrilla c.f. dendyi marine sponge. Denigrins H-L represent the first examples of sulfated denigrins, with denigrins H and I (1-2), as derivatives of denigrin D, containing a pyrrolone core, and denigrins J-L (3-5), as derivatives of denigrin E (6), containing a pyrrole core. Their structures were elucidated by interpretation of 1D and 2D NMR spectroscopic data, ESI, and HR-ESI-MS spectrometric data, as well as comparison with literature data. Compounds 1-5, along with six known compounds previously isolated from the same extract, showed minimal cytotoxicity against the HeLa cervical cancer cell line.


Assuntos
Alcaloides , Poríferos , Pirróis , Animais , Poríferos/química , Humanos , Nova Zelândia , Pirróis/farmacologia , Pirróis/química , Pirróis/isolamento & purificação , Células HeLa , Alcaloides/farmacologia , Alcaloides/química , Alcaloides/isolamento & purificação , Sulfatos/química , Sulfatos/farmacologia , Estrutura Molecular , Espectroscopia de Ressonância Magnética , Antineoplásicos/farmacologia , Antineoplásicos/química , Antineoplásicos/isolamento & purificação
12.
Mar Drugs ; 22(5)2024 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-38786623

RESUMO

Mycoplasma pneumoniae, a notable pathogen behind respiratory infections, employs specialized proteins to adhere to the respiratory epithelium, an essential process for initiating infection. The role of glycosaminoglycans, especially heparan sulfate, is critical in facilitating pathogen-host interactions, presenting a strategic target for therapeutic intervention. In this study, we assembled a glycan library comprising heparin, its oligosaccharide derivatives, and a variety of marine-derived sulfated glycans to screen the potential inhibitors for the pathogen-host interactions. By using Surface Plasmon Resonance spectroscopy, we evaluated the library's efficacy in inhibiting the interaction between M. pneumoniae adhesion proteins and heparin. Our findings offer a promising avenue for developing novel therapeutic strategies against M. pneumoniae infections.


Assuntos
Heparina , Mycoplasma pneumoniae , Polissacarídeos , Mycoplasma pneumoniae/efeitos dos fármacos , Heparina/farmacologia , Heparina/química , Polissacarídeos/farmacologia , Polissacarídeos/química , Organismos Aquáticos , Humanos , Adesinas Bacterianas/metabolismo , Adesinas Bacterianas/efeitos dos fármacos , Aderência Bacteriana/efeitos dos fármacos , Pneumonia por Mycoplasma/tratamento farmacológico , Pneumonia por Mycoplasma/microbiologia , Antibacterianos/farmacologia , Antibacterianos/química , Animais , Interações Hospedeiro-Patógeno , Sulfatos/química , Sulfatos/farmacologia
13.
Environ Sci Pollut Res Int ; 31(21): 31213-31223, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38625470

RESUMO

The establishment of sulfate (SO42-) reduction during methanogenesis may considerably hinder the efficient energetic exploitation of methane, once removing sulfide from biogas is obligate and can be costly. In addition, sulfide generation can negatively impact the performance of methanogens by triggering substrate competition and sulfide inhibition. This study investigated the impacts of removing SO42- during fermentation on the performance of a second-stage methanogenic continuous reactor (R2), comparing the results with those obtained in a single-stage system (R1) fed with SO42--rich wastewater (SO42- of up to 400 mg L-1, COD/SO42- of 3.12-12.50). The organic load (OL) was progressively increased to 5.0 g COD d-1 in both reactors, showing completely discrepant performances. Sulfate-reducing bacteria outperformed methanogens in the consumption for organic matter during the start-up phase (OL = 2.5 g COD d-1) in R1, directing up to 73% of the electron flow to SO42- reduction. An efficient methanogenic activity was established in R1 only after decreasing the OL to 0.625 g COD d-1, after which methanogenesis prevailed by consuming ca. 90% of the removed COD. Nevertheless, high sulfide proportions (up to 3.1%) were measured in biogas. Conversely, methanogenesis was promptly established in R2, resulting in a methane-rich (> 80%) and sulfide-free biogas regardless of the operating condition. From an economic perspective, processing the biogas evolved from R2 would be cheaper, although the techno-economic impacts of managing the sulfur pollution in the fermentative reactor still need to be understood.


Assuntos
Reatores Biológicos , Metano , Sulfetos , Metano/metabolismo , Águas Residuárias/química , Sulfatos/metabolismo , Separação de Fases
14.
Environ Sci Pollut Res Int ; 31(21): 31108-31122, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38625474

RESUMO

Salinity stress significantly constrains agricultural productivity and vegetation decline worldwide, particularly in Iran. Potassium, the second most prevalent nutrient in plants, is well known to be essential for cell metabolism. Here, the effects of potassium fertilizer in two biogenic nanoparticles (K-NPs) and conventional (potassium sulfate) forms (0.1 mg/ml) on Melissa officinalis L. under salinity (0, 50, 100, and 150 mM) were investigated. The results demonstrated that stress markers (electrolyte leakage, malondialdehyde, and hydrogen peroxide) increased as salinity levels increased. Plant growth parameters (shoot and root length, fresh and dry weight of shoot and root) and physiological and photosynthetic parameters (stomatal conductance, relative water content, chlorophyll fluorescence, and photosynthetic pigments) were reduced in salinized plants. The highest reduction in fresh weight root, dry weight root, fresh weight shoot, dry weight shoot, root length, and shoot length was recorded under 150 mM NaCl by 30.2%, 51.6%, 30.5%, 24.7%, 26.4%, and 21%, respectively. In contrast, bulk potassium sulfate and K-NPs increased these parameters. Furthermore, K-NPs improved M. officinalis tolerance to NaCl toxicity by enhancing the content of osmolytes such as proline, soluble sugars, and antioxidant enzymes, improving antioxidant contents such as phenols, tannins, anthocyanins, and flavonoids; increasing total protein; and lowering stress markers in plant tissues. Given the results of the physiological, biochemical, and phytochemical parameters obtained from this study, it can be stated that K-NPs, in comparison to the conventional form of potassium fertilizer, exhibit a greater potential to mitigate damages caused by salinity stress in M. officinalis plants.


Assuntos
Melissa , Potássio , Estresse Salino , Sulfatos , Melissa/efeitos dos fármacos , Estresse Salino/efeitos dos fármacos , Nanopartículas , Compostos Fitoquímicos , Irã (Geográfico) , Folhas de Planta/efeitos dos fármacos , Compostos de Potássio , Fotossíntese/efeitos dos fármacos
15.
Environ Sci Pollut Res Int ; 31(21): 31577-31589, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38635092

RESUMO

Sulfate wastewater has a wide range of sources and greatly harms water, soil, and plants. Iron-carbon microelectrolysis (IC-ME) is a potentially sustainable strategy to improve the treatment of sulfate (SO42-) wastewater by sulfate-reducing bacteria (SRB). In this study, an iron-carbon mixed micro-electrolysis bioreactor (R1), iron-carbon layered bioreactor (R2), activated carbon bioreactor (R3), and scrap iron filing bioreactor (R4) were constructed by up-flow column experimental device. The performance and mechanism of removing high-concentration sulfate wastewater under different sulfate concentrations, hydraulic retention times (HRT), and chemical oxygen demand (COD)/SO42- were discussed. The results show that the iron-carbon microelectrolysis-enhanced SRB technology can remove high-concentration sulfate wastewater, and the system can still operate normally at low pH. In the high hydraulic loading stage (HRT = 12 h, COD/SO42- = 1.4), the SO42- removal rate of the R1 reactor reached 98.08%, and the ORP value was stable between - 350 and - 450 mV, providing a good ORP environment for SRB. When HRT = 12 h and influent COD/SO42- = 1.4, the R1 reactor sulfate removal rate reached 96.7%. When the influent COD/SO42- = 0.7, the sulfate removal rate was 52.9%, higher than the control group. Biological community analysis showed that the abundance of SRB in the R1 reactor was higher than that in the other three groups, indicating that the IC-ME bioreactor could promote the enrichment of SRB and improve its population competitive advantage. It can be seen that the synergistic effect between IC-ME and biology plays a vital role in the treatment of high-concentration sulfate wastewater and improves the biodegradability of sulfate. It is a promising process for treating high-concentration sulfate wastewater.


Assuntos
Reatores Biológicos , Carbono , Ferro , Sulfatos , Eliminação de Resíduos Líquidos , Águas Residuárias , Águas Residuárias/química , Eliminação de Resíduos Líquidos/métodos , Bactérias/metabolismo , Análise da Demanda Biológica de Oxigênio
16.
FEMS Microbiol Ecol ; 100(6)2024 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-38658197

RESUMO

The dihydrogen (H2) sector is undergoing development and will require massive storage solutions. To minimize costs, the conversion of underground geological storage sites, such as deep aquifers, used for natural gas storage into future underground hydrogen storage sites is the favored scenario. However, these sites contain microorganisms capable of consuming H2, mainly sulfate reducers and methanogens. Methanogenesis is, therefore expected but its intensity must be evaluated. Here, in a deep aquifer used for underground geological storage, 17 sites were sampled, with low sulfate concentrations ranging from 21.9 to 197.8 µM and a slow renewal of formation water. H2-selected communities mainly were composed of the families Methanobacteriaceae and Methanothermobacteriaceae and the genera Desulfovibrio, Thermodesulfovibrio, and Desulforamulus. Experiments were done under different conditions, and sulfate reduction, as well as methanogenesis, were demonstrated in the presence of a H2 or H2/CO2 (80/20) gas phase, with or without calcite/site rock. These metabolisms led to an increase in pH up to 10.2 under certain conditions (without CO2). The results suggest competition for CO2 between lithoautotrophs and carbonate mineral precipitation, which could limit microbial H2 consumption.


Assuntos
Água Subterrânea , Hidrogênio , Metano , Gás Natural , Metano/metabolismo , Água Subterrânea/microbiologia , Hidrogênio/metabolismo , Sulfatos/metabolismo , Methanobacteriaceae/metabolismo , Methanobacteriaceae/genética , Methanobacteriaceae/crescimento & desenvolvimento , Dióxido de Carbono/metabolismo , Bactérias/metabolismo , Bactérias/genética , Bactérias/classificação , Concentração de Íons de Hidrogênio , Microbiologia da Água
17.
Chemosphere ; 357: 142054, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38642774

RESUMO

Anthropogenic sulfate loading into otherwise low-sulfate freshwater systems can cause significant ecological consequences as a biogeochemical stressor. To address this challenge, in situ bioremediation technologies have been developed to leverage naturally occurring microorganisms that transform sulfate into sulfide rather than implementing resource-intensive physio-chemical processes. However, bioremediation technologies often require the supply of electron donors to facilitate biological sulfate reduction. Bioelectrochemical systems (BES) can be an alternative approach for supplying molecular hydrogen as an electron donor for sulfate-reducing bacteria through water electrolysis. Although the fundamental mechanisms behind BESs have been studied, limited research has evaluated the design and operational parameters of treatment systems when developing BESs on a scale relevant to environmental systems. This study aimed to develop an application-based mathematical model to evaluate the performance of BESs across a range of reactor configurations and operational modes. The model was based on sulfate transformation by hydrogenotrophic sulfate-reducing bacteria coupled with the recovery of solid iron sulfide species formed by the oxidative dissolution of dissolved ferrous iron from a stainless steel anode. Sulfate removal closely corresponded to the rate of electrolytic hydrogen production and hydraulic residence time but was less sensitive to specific microbial rate constants. The mathematical model results were compared to experimental data from a pilot-scale BES tested with nonacidic mine drainage as a case study. The close agreement between the mathematical model and the pilot-scale BES experiment highlights the efficacy of using a mathematical model as a tool to develop a conceptual design of a scaled-up treatment system.


Assuntos
Biodegradação Ambiental , Água Doce , Modelos Teóricos , Sulfatos , Poluentes Químicos da Água , Sulfatos/metabolismo , Água Doce/química , Poluentes Químicos da Água/análise , Poluentes Químicos da Água/metabolismo , Reatores Biológicos , Ecossistema , Oxirredução , Técnicas Eletroquímicas/métodos
18.
Bioresour Technol ; 401: 130747, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38677382

RESUMO

Sulfur-driven autotrophic denitrification (SdAD) is a promising nitrogen removing process, but its applications were generally constrained by conventional electron donors (i.e., thiosulfate (Na2S2O3)) with high valence and limited bioavailability. Herein, an immobilized electron donor by loading elemental sulfur on the surface of polyurethane foam (PFSF) was developed, and its feasibility for SdAD was investigated. The denitrification efficiency of PFSF was 97.3%, higher than that of Na2S2O3 (91.1%). Functional microorganisms (i.e., Thiobacillus and Sulfurimonas) and their metabolic activities (i.e., nir and nor) were substantially enhanced by PFSF. PFSF resulted in the enrichment of sulfate-reducing bacteria, which can reduce sulfate (SO42-). It attenuated the inhibitory effect of SO42-, whereas the generated product (hydrogen sulfide) also served as an electron donor for SdAD. According to the economic evaluation, PFSF exhibited strong market potential. This study proposes an efficient and low-cost immobilized electron donor for SdAD and provides theoretical support to its practical applications.


Assuntos
Processos Autotróficos , Desnitrificação , Nitrogênio , Enxofre , Enxofre/metabolismo , Enxofre/química , Elétrons , Thiobacillus/metabolismo , Poliuretanos/química , Sulfatos/metabolismo , Bactérias/metabolismo , Tiossulfatos/química , Tiossulfatos/farmacologia
19.
Chemosphere ; 357: 141975, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38615960

RESUMO

This study investigated the determinants of personal exposures (PE) to coarse (PM2.5-10) and fine particulate matter (PM2.5) for elderly communities in Hong Kong. The mean PE PM2.5 and PM2.5-10 were 23.6 ± 10.8 and 13.5 ± 22.1 µg/m3, respectively during the sampling period. Approximately 76% of study subjects presented statistically significant differences between PE and ambient origin for PM2.5 compared to approximately 56% for PM2.5-10, possibly due to the coarse-size particles being more influenced by similar sources (road dust and construction dust emissions) compared to the PM2.5 particles. Individual PE to ambient (P/A) ratios for PM2.5 all exceeded unity (≥1), suggesting the dominant influences of non-ambient particles contributed towards total PE values. There were about 80% individual P/A ratios (≤1) for PM2.5-10, implying possible effective infiltration prevention of larger size particulate matter particles leading to dominant influences from the outdoor sources. The higher concentration of NO3- and SO42- in PM2.5-10 compared to PM2.5 suggests possible heterogeneous reactions of alkaline minerals leading to the formation of NO3- and SO42- in PM2.5-10 particles. The PE and ambient OC/EC ratios in PM2.5 (8.8 ± 3.3 and 10.4 ± 22.4, respectively) and in PM2.5-10 (6.0 ± 1.9 and 3.0 ± 1.1, respectively) suggest possible secondary formed OC from surrounding rural areas. Heterogeneous distributions (COD >0.2) between the PE and ambient concentrations were found for both the PM2.5 and PM2.5-10 samples. The calibration coefficient as the association between personal and surrogate exposure measure of PE to PM2.5 (0.84) was higher than PM2.5-10 (0.52). The findings further confirm that local sources were the dominant contributor to the coarse particles and these coefficients can potentially be used to estimate different PE to PM2.5 and PM2.5-10 conditions. A comprehensive understanding of the PE to determinants in coarse particles is essential to further reduce potential exposure misclassification.


Assuntos
Poluição do Ar , Exposição por Inalação , Material Particulado , Humanos , Pessoa de Meia-Idade , Idoso , Idoso de 80 Anos ou mais , Masculino , Feminino , Material Particulado/análise , Exposição por Inalação/estatística & dados numéricos , Poluição do Ar/estatística & dados numéricos , Hong Kong , Tamanho da Partícula , Monitoramento Ambiental , Nitratos/análise , Sulfatos/análise
20.
Environ Geochem Health ; 46(5): 174, 2024 Apr 09.
Artigo em Inglês | MEDLINE | ID: mdl-38592609

RESUMO

The effects of long-term exposure to fine particulate matter (PM2.5) constituents on chronic kidney disease (CKD) are not fully known. This study sought to examine the association between long-term exposure to major PM2.5 constituents and CKD and look for potential constituents contributing substantially to CKD. This study included 81,137 adults from the 2018 to 2019 baseline survey of China Multi-Ethnic Cohort. CKD was defined by the estimated glomerular filtration rate. Exposure concentration data of 7 major PM2.5 constituents were assessed by satellite remote sensing. Logistic regression models were used to estimate the effect of each PM2.5 constituent exposure on CKD. The weighted quantile sum regression was used to estimate the effect of mixed exposure to all constituents. PM2.5 constituents had positive correlations with CKD (per standard deviation increase), with ORs (95% CIs) of 1.20 (1.02-1.41) for black carbon, 1.27 (1.07-1.51) for ammonium, 1.29 (1.08-1.55) for nitrate, 1.20 (1.01-1.43) for organic matter, 1.25 (1.06-1.46) for sulfate, 1.30 (1.11-1.54) for soil particles, and 1.63 (1.39-1.91) for sea salt. Mixed exposure to all constituents was positively associated with CKD (1.68, 1.32-2.11). Sea salt was the constituent with the largest weight (0.36), which suggested its importance in the PM2.5-CKD association, followed by nitrate (0.32), organic matter (0.18), soil particles (0.10), ammonium (0.03), BC (0.01). Sulfate had the least weight (< 0.01). Long-term exposure to PM2.5 sea salt and nitrate may contribute more than other constituents in increasing CKD risk, providing new evidence and insights for PM2.5-CKD mechanism research and air pollution control strategy.


Assuntos
Compostos de Amônio , Insuficiência Renal Crônica , Humanos , Adulto , Nitratos , China/epidemiologia , Material Particulado/toxicidade , Insuficiência Renal Crônica/induzido quimicamente , Insuficiência Renal Crônica/epidemiologia , Solo , Sulfatos , Óxidos de Enxofre
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