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1.
Talanta ; 251: 123759, 2023 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-35952499

RESUMO

Heart failure (HF) is a chronic cardiovascular disease that represents main cause of mortality worldwide, particularly for elderly. N-terminal pro-brain natriuretic peptide (NT-proBNP) was identified as the gold standard biomarker for HF diagnosis and therapy monitoring. Presently, saliva analysis represents an emerging and powerful tool for clinical applications and electrochemical immunosensors have shown their potential in Healthcare applications as selective and reliable systems for detecting clinical biomarkers. This work presents the detection of NT-proBNP in saliva samples by an immunologically modified Field effect Transistor (IMFET). TESUD ((11-triethoxysilyl) undecanal) was used as cross-linker to immobilise anti-NT-proBNP antibody onto the device. Our IMFET that was then tested in different matrices (e.g. phosphate buffered saline (PBS), artificial saliva and human saliva) using electrochemical impedance spectroscopy (EIS), and it resulted selective to NT-proBNP with good sensitivity (detection limit of 0.02 pg/mL) and a wide linear range (0.02-1 pg/mL and 0.5-20 pg/mL). Finally, NT-proBNP concentration in ten saliva samples was determined by performing the standard addition method. An enzyme-linked immunosorbent assay was used for confirming IMFET results, highlighting both IMFET accuracy (analyte recovery of 99 ± 8%) and precision (coefficient of variation always <10%), and supporting the suitability of the device for determining salivary NT-proBNP.


Assuntos
Técnicas Biossensoriais , Insuficiência Cardíaca , Idoso , Humanos , Biomarcadores , Insuficiência Cardíaca/diagnóstico , Imunoensaio , Peptídeo Natriurético Encefálico , Fragmentos de Peptídeos , Fosfatos , Saliva , Saliva Artificial , Volume Sistólico , Técnicas Eletroquímicas
2.
J Ethnopharmacol ; 300: 115752, 2023 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-36174807

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: Peganum harmala L. is a traditional medicinal plant used for centuries in folk medicine. It has a wide array of therapeutic attributes, which include hypoglycemic, sedative, anti-inflammatory, and antioxidant properties. The fruit decoction of this plant was claimed by Avicenna as traditional therapy for urolithiasis. Also, P. harmala seed showed a clinical reduction in kidney stone number and size in patients with urolithiasis. AIM OF THE STUDY: In light of the above-mentioned data, the anti-urolithiatic activities of the seed extracts and the major ß-carboline alkaloids of P. harmala were investigated. MATERIALS AND METHODS: Extraction, isolation, and characterization of the major alkaloids were performed using different chromatographic and spectral techniques. The in vivo anti-urolithiatic action was evaluated using ethylene glycol (EG)-induced urolithiasis in rats by studying their mitigating effects on the antioxidant machinery, serum toxicity markers (i.e. nitrogenous waste, such as blood urea nitrogen, uric acid, urea, and creatinine), minerals (such as Ca, Mg, P, and oxalate), kidney injury marker 1 (KIM-1), and urinary markers (i.e. urine pH and urine output). RESULTS: Two major alkaloids, harmine (P1) and harmalacidine HCl (P2), were isolated and in vivo evaluated alongside the different extracts. The results showed that P. harmala and its constituents/fractions significantly reduced oxidative stress at 50 mg/kg body weight, p.o., as demonstrated by increased levels of glutathione (GSH), glutathione reductase (GR), glutathione peroxidase (GPx), and catalase (CAT) in kidney homogenate as compared to the EG-treated group. Likewise, the total extract, pet. ether fraction, n-butanol fraction, and P1, P2 alleviated malondialdehyde (MDA) as compared to the EG-treated group. Serum toxicity markers like blood urea nitrogen (BUN), creatinine, uric acid, urea, kidney injury molecule-1 (Kim-1), calcium, magnesium, phosphate, and oxalate levels were decreased by total extract, pet. ether fraction, n-butanol fraction, P1, and P2 as compared to the EG-treated group. Inflammatory markers like NFκ-B and TNF-α were also downregulated in the kidney homogenate of treatment groups as compared to the EG-treated group. Moreover, urine output and urine pH were significantly increased in treatment groups as compared to the EG-treated group deciphering anti-urolithiatic property of P. harmala. Histopathological assessment by different staining patterns also supported the previous findings and indicated that treatment with P. harmala caused a gradual recovery in damaged glomeruli, medulla, interstitial spaces and tubules, and brown calculi materials as compared to the EG-treated group. CONCLUSION: The current research represents scientific evidence on the use of P. harmala and its major alkaloids as an effective therapy in the prevention and management of urolithiasis.


Assuntos
Alcaloides , Cálculos Renais , Peganum , Urolitíase , 1-Butanol , Alcaloides/farmacologia , Animais , Antioxidantes , Cálcio , Oxalato de Cálcio/urina , Catalase , Creatinina , Éteres , Etilenoglicol/uso terapêutico , Etilenoglicol/toxicidade , Glutationa , Glutationa Peroxidase , Glutationa Redutase , Harmina , Hipnóticos e Sedativos/uso terapêutico , Hipoglicemiantes/uso terapêutico , Cálculos Renais/tratamento farmacológico , Magnésio , Malondialdeído , Peganum/química , Fosfatos , Extratos Vegetais , Ratos , Fator de Necrose Tumoral alfa , Ureia , Ácido Úrico , Urolitíase/induzido quimicamente , Urolitíase/tratamento farmacológico , Urolitíase/patologia
3.
J Hazard Mater ; 441: 129886, 2023 01 05.
Artigo em Inglês | MEDLINE | ID: mdl-36088881

RESUMO

Mismanaged plastic waste interacts with secondary environmental pollutants, potentially aggravating their impact on ecosystems and human health. Here we characterized the natural and artificial radionuclides in polyethylene terephthalate (PET) bottles collected from the industrial littoral discharge of a phosphate fertilizer plant. The activity concentrations in littered bottles ranged from 0.47 (208Tl) to 12.70 Bq·kg-1 (226Ra), with a mean value of 5.30 Bq·kg-1. All the human health risk assessment indices (annual intake, annual effective dose, and excess lifetime cancer risk) estimated for radionuclides associated with ingestion and inhalation of microplastics were below international safety limits. Our results demonstrated that PET can be loaded with natural and artificial radionuclides, and potentially act as a carrier to transfer radionuclides to humans, posing a new potential health risk. Increased use, mismanagement and fragmentation of plastic waste, and continued interaction of plastic waste with radioelements may lead to enhanced radiation exposure in the future.


Assuntos
Poluentes Ambientais , Plásticos , Ecossistema , Fertilizantes , Humanos , Microplásticos , Fosfatos , Polietilenotereftalatos , Radioisótopos , Radioisótopos de Tálio
4.
J Environ Sci (China) ; 124: 429-439, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36182151

RESUMO

Antibiotic pollution imposes urgent threats to public health and microbial-mediated ecological processes. Existing studies have primarily focused on bacterial responses to antibiotic pollution, but they ignored the microeukaryotic counterpart, though microeukaryotes are functionally important (e.g., predators and saprophytes) in microbial ecology. Herein, we explored how the assembly of sediment microeukaryotes was affected by increasing antibiotic pollution at the inlet (control) and across the outlet sites along a shrimp wastewater discharge channel. The structures of sediment microeukaryotic community were substantially altered by the increasing nutrient and antibiotic pollutions, which were primarily controlled by the direct effects of phosphate and ammonium (-0.645 and 0.507, respectively). In addition, tetracyclines exerted a large effect (0.209), including direct effect (0.326) and indirect effect (-0.117), on the microeukaryotic assembly. On the contrary, the fungal subcommunity was relatively resistant to antibiotic pollution. Segmented analysis depicted nonlinear responses of microeukaryotic genera to the antibiotic pollution gradient, as supported by the significant tipping points. We screened 30 antibiotic concentration-discriminatory taxa of microeukaryotes, which can quantitatively and accurately predict (98.7% accuracy) the in-situ antibiotic concentration. Sediment microeukaryotic (except fungal) community is sensitive to antibiotic pollution, and the identified bioindicators could be used for antibiotic pollution diagnosis.


Assuntos
Compostos de Amônio , Antibacterianos , Biomarcadores Ambientais , Fosfatos , Tetraciclinas , Águas Residuárias
5.
J Environ Sci (China) ; 124: 50-60, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36182158

RESUMO

Phosphorus (P) in sediments plays an important role in shallow lake ecosystems and has a major effect on the lake environment. The mobility and bioavailability of P primarily depend on the contents of different P forms, which in turn depend on the sedimentary environment. Here, sediment samples from Baiyangdian (BYD) lake were collected and measured by the Standards, Measurements, and Testing procedure and Phosphorus-31 nuclear magnetic resonance spectroscopy (31P NMR) to characterize different P forms and their relationships with sediment physicochemical properties. The P content in the sediments varied in different areas and had characteristics indicative of exogenous river input. Inorganic P (334-916 mg/kg) was the dominant form of P. The 31P NMR results demonstrated that orthophosphate monoesters (16-110 mg/kg), which may be a source of P when redox conditions change, was the dominant form of organic P (20-305 mg/kg). The distribution of P forms in each region varied greatly because of the effects of anthropogenic activities, and the regions affected by exogenous river input had a higher content of P and a higher risk of P release. Principal component analysis indicated that P bound to Fe, Al, and Mn oxides and hydroxides (NaOH-P) and organic P were mainly derived from industrial and agricultural pollution, respectively. Redundancy analysis indicated that increases in pH lead to the release of NaOH-P. Organic matter plays an important role in the organic P biogeochemical cycle, as it acts as a sink and source of organic P.


Assuntos
Fósforo , Poluentes Químicos da Água , China , Ecossistema , Monitoramento Ambiental/métodos , Sedimentos Geológicos/química , Óxidos/análise , Fosfatos/análise , Fósforo/análise , Hidróxido de Sódio , Poluentes Químicos da Água/análise
6.
J Environ Sci (China) ; 124: 699-711, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36182175

RESUMO

Numerous studies support that biodiversity predict most to ecosystem functioning, but whether other factors display a more significant direct impact on ecosystem functioning than biodiversity remains to be studied. We investigated 398 samples of the phytoplankton phosphorus resource use efficiency (RUEP = chlorophyll-a concentration/dissolved phosphate) across two seasons in nine plateau lakes in Yunnan Province, China. We identified the main contributors to phytoplankton RUEP and analyzed their potential influences on RUEP at different lake trophic states. The results showed that total nitrogen (TN) contributed the most to RUEP among the nine lakes, whereas community turnover (measured as community dissimilarity) explained the most to RUEP variation across the two seasons. Moreover, TN also influenced RUEP by affecting biodiversity. Species richness (SR), functional attribute diversity (FAD2), and dendrogram-based functional diversity (FDc) were positively correlated with RUEP in both seasons, while evenness was negatively correlated with RUEP at the end of the rainy season. We also found that the effects of biodiversity and turnover on RUEP depended on the lake trophic states. SR and FAD2 were positively correlated with RUEP in all three trophic states. Evenness showed a negative correlation with RUEP at the eutrophic and oligotrophic levels, but a positive correlation at the mesotrophic level. Turnover had a negative influence on RUEP at the eutrophic level, but a positive influence at the mesotrophic and oligotrophic levels. Overall, our results suggested that multiple factors and nutrient states need to be considered when the ecosystem functioning predictors and the biodiversity-ecosystem functioning relationships are investigated.


Assuntos
Lagos , Fitoplâncton , China , Clorofila , Ecossistema , Nitrogênio/análise , Nutrientes , Fosfatos , Fósforo/análise
7.
Food Chem ; 400: 134001, 2023 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-36084586

RESUMO

Flavonoids are associated with health benefits, but most of them have poor oral bioavailability due to their extremely low aqueous solubility. Flavonoid O-phosphorylation suggests a potent modification to solve the problems. Here, we isolated, identified and characterized an unprecedented phosphotransferase, flavonoid phosphate synthetase (BsFPS), from B. subtilis. The enzyme catalyzes the ATP-dependent phosphorylation of flavonoid to generate flavonoid monophosphates, AMP and orthophosphate. BsFPS is a promiscuous phosphotransferase that efficiently catalyzes structurally-diverse flavonoids, including isoflavones, flavones, flavonols, flavanones and flavonolignans. Based on MS and NMR analysis, the phosphorylation mainly occurs on the hydroxyl group at C-7 of A-ring or C-4' of B-ring in flavonoid skeleton. Notably, BsFPS is regioselective for the ortho-3',4'-dihydroxy moiety of catechol-containing structures, such as luteolin and quercetin, to produce phosphate conjugates at C-4' or C-3' of B-ring. Our findings highlight the potential for developing biosynthetic platform to obtain new phosphorylated flavonoids for pharmaceutical and nutraceutical applications.


Assuntos
Flavanonas , Flavonas , Flavonolignanos , Isoflavonas , Monofosfato de Adenosina , Trifosfato de Adenosina , Bacillus subtilis , Catecóis , Flavonoides/química , Ligases , Luteolina , Fosfatos , Fosfotransferases , Quercetina
8.
Methods Mol Biol ; 2555: 103-114, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36306081

RESUMO

Phosphate release from inorganic and organic phosphorus compounds can be enzymatically mediated. Phosphate-releasing enzymes, comprising acid and alkaline phosphatases, are recognized as useful biocatalysts in applications such as plant and animal nutrition, bioremediation, and diagnostic analysis. Here, we describe a functional metagenomics approach enabling rapid identification of genes encoding these enzymes. The target genes are detected based on small- and large-insert metagenomic libraries derived from diverse environments. This approach has the potential to unveil entirely new phosphatase families or subfamilies and members of known enzyme classes that hydrolyze phosphomonoester bonds such as phytases. Additionally, we provide a strategy for efficient heterologous expression of phosphatase genes.


Assuntos
6-Fitase , Metagenômica , Metagenoma , Monoéster Fosfórico Hidrolases/genética , Monoéster Fosfórico Hidrolases/metabolismo , 6-Fitase/genética , Fosfatos
9.
Sci Total Environ ; 855: 158831, 2023 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-36165822

RESUMO

Lead (Pb) contamination is one of the most significant exposure hazards to human health. Contaminated soil particles may be eroded and transferred either to the atmosphere (<10 µm) or to streams; or they may be incidentally ingested (<200 µm). Among strategies for the long-term management of this risk, one of the most cost-effective is the reduction of Pb mobility and bioavailability via amendment with phosphorus-containing materials. To clarify the effectiveness of P amendment in reducing Pb mobility and bioaccessibility in different soil size fractions, an experiment was performed by adding a soluble P compound to a historically contaminated urban soil (RO), a mining soil (MI), and an uncontaminated spiked soil (SP) at different P:Pb molar ratios (2.5:1, 5:1, and 15:1). In the <10 µm fraction of soils, P addition reduced bioaccessible Pb only in the SP soil at the highest dose, with little to no effect on RO and MI soils. Similarly, in the coarse fraction, Pb was immobilized only in the SP soil with all three P doses. These results were probably due to the higher stability of Pb in historically contaminated soils, where Pb dissolution is the limiting factor to the formation of insoluble Pb compounds. The bioaccessible proportion of Pb (using SBET method) was higher than 70 % of the total Pb in all soils and was similar in both fine and coarse particle fractions. Due to the enrichment of Pb in finer particles, this implies possible adverse effects to the environment or to human health if these particles escape from the soil. These results call for increasing attention to the effect of remediation activities on fine soil particles, considering their significant environmental role especially in urban and in historically low or moderately contaminated areas.


Assuntos
Poluentes do Solo , Humanos , Poluentes do Solo/análise , Fosfatos , Chumbo , Solo , Disponibilidade Biológica
10.
Sci Total Environ ; 856(Pt 1): 158779, 2023 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-36116658

RESUMO

In this study, brominated flame retardants (BFRs), phthalates, and organophosphate flame retardants (PFRs) were analyzed in indoor household dust collected during the COVID-19 related strict lockdown (April-July 2020) period. Floor dust samples were collected from 40 households in Jeddah, Saudi Arabia. The levels of most of the analyzed chemicals were visibly high and for certain chemicals multifold high in analyzed samples compared to earlier studies on indoor dust from Jeddah. Bis (2-ethylhexyl) phthalate (DEHP) was the primary chemical in these dust samples, with a median concentration of 769,500 ng/g of dust. Tris (2-butoxy ethyl) phosphate (TBEP) and Decabromodiphenyl ether (BDE 209) contributed the highest among PFRs and BFRs with median levels of 5990 and 940 ng/g of dust, respectively. The estimated daily exposure in the worst case scenario (23,700 ng/kg bw/day) for Saudi children was above the reference dose (20,000 ng/kg bw/day) for DEHP, and the hazardous index (HI) was also >1. The long-term carcinogenic risk was above the 1 × 10-5, indicating a risk to the health of Saudi young children from getting exposed to DEHP from indoor dust. This study draws attention to the increased indoor pollution during the lockdown period when all of the daily activities by adults and children were performed indoors, which negatively impacted human health, as suggested by the calculated risk. However, the current study has limitations and warrants more monitoring studies from different parts of the world to understand the phenomenon. At the same time, this study also highlights another side of COVID-19 related to our lives.


Assuntos
Poluição do Ar em Ambientes Fechados , COVID-19 , Dietilexilftalato , Retardadores de Chama , Criança , Adulto , Humanos , Pré-Escolar , Retardadores de Chama/análise , Poeira , Organofosfatos/análise , COVID-19/epidemiologia , Poluição do Ar em Ambientes Fechados/análise , Exposição Ambiental/análise , Controle de Doenças Transmissíveis , Éteres Difenil Halogenados/análise , Compostos Organofosforados/análise , Fosfatos
11.
J Hazard Mater ; 443(Pt A): 130153, 2023 02 05.
Artigo em Inglês | MEDLINE | ID: mdl-36244105

RESUMO

Research on the environmental occurrence and behavior of organophosphate esters (OPEs) is very imperative. In this study, 12 targeted OPEs in the water and sediment samples collected from the middle and lower streams of the Yellow River (YR) and its tributaries during the dry, normal, and wet season were analyzed, to reveal their concentration, spatiotemporal variations, and ecological risks. The results indicated that the total concentration of OPEs (ΣOPE) ranged from 97.66 to 2433.30 ng/L in water, and from 47.33 to 234.08 ng/g in sediment. Tris(2-chloroethyl) phosphate (TCEP), tris(2-chloroisopropyl)phosphate (TCIPP), and triethyl phosphate (TEP) were the most abundant OPEs in the surface water and sediment. The OPEs levels in river water were ranked as the order of dry > normal > wet season. The ΣOPE concentrations in water and sediment were relatively high in the central and lower sections of the YR. The resorcinol-bis(diphenyl)phosphate (RDP) effectively transferred from the overlying water to the sediment. TCEP and RDP posed relatively higher ecological risk than other OPEs. Municipal and chemical industrial discharge might be sources of OPEs in the middle and lower streams of the YR.


Assuntos
Retardadores de Chama , Poluentes Químicos da Água , Retardadores de Chama/análise , Monitoramento Ambiental/métodos , Água , Poluentes Químicos da Água/análise , Ésteres , Organofosfatos/toxicidade , Fosfatos , China
12.
J Hazard Mater ; 443(Pt A): 130149, 2023 02 05.
Artigo em Inglês | MEDLINE | ID: mdl-36252405

RESUMO

In this study, a newly isolated strain Amycolatopsis sp. FT-1 was confirmed to be an efficient tris-(2-chloroisopropyl) phosphate (TCPP) degrader. The maximum degradation efficiency of 100 % was achieved when glucose concentration was 6.0 g/L, TCPP concentration was 1.1 mg/L, pH was 6.3 and temperature was 35 °C. Proteome analysis indicated that TCPP was transformed into diester, monoester and ketone product through hydrolysis by phosphoesterase and oxidation mediated by proteins involved in bio-Fenton reaction. The increased expression of proteins serving as organic hydroperoxides scavenger and two subunits of xanthine dehydrogenase enabled Amycolatopsis sp. FT-1 to defend against TCPP-induced oxidative damage. Meanwhile, proteins involved in the resistance to proteotoxic stress were found to be up-regulated, including Hsp70 protein, ATP-dependent Clp protease proteolytic subunit, elongation factor G and trehalose synthesis-related enzymes. The overexpression of TetR/AcrR family transcriptional regulator and multidrug efflux transporter also benefited the survival of Amycolatopsis sp. FT-1 under TCPP stress. Luminescent bacteria test showed that biotoxicity of TCPP was remarkably decreased after biodegradation by Amycolatopsis sp. FT-1. To the best of our knowledge, this is the first study to report the biotransformation of TCPP by pure strain and to offer important insights into the proteomic mechanisms of TCPP microbial degradation.


Assuntos
Amycolatopsis , Fosfatos , Proteômica , Organofosfatos , Biodegradação Ambiental
13.
J Biomed Mater Res B Appl Biomater ; 111(1): 95-102, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-35851987

RESUMO

The study verified the influence of calcium orthophosphate (CaP):glass ratio on the degree of conversion and mechanical properties of resin-based composites containing either TEGDMA-functionalized dicalcium phosphate anhydrous (DCPA) or non-functionalized DCPA particles. The null hypotheses were that the evaluated variables are not affected by (1) CaP:glass ratio or (2) DCPA functionalization. DCPA particles were synthesized and half of them were functionalized with TEGDMA. Particle characterization included x-ray diffraction, elemental analysis, laser scattering, helium picnometry and scanning electron microscopy. Two series of composites were prepared containing either DCPA-NF (non-functionalized) or DCPA-F (functionalized), with total inorganic content of 50 vol % and DCPA:silanized barium glass (BG) ratios from 10:40 to 50:0. A composite containing 50 vol % BG was tested as control. DC was determined using FTIR spectroscopy. Biaxial flexural strength and modulus were tested after 24 h in water. Data were analyzed using Kruskal-Wallis/Dunn (flexural properties) or analysis of variance/Tukey tests (DC). Materials with similar actual DCPA contents were compared using Student's t test (alpha: 0.05). DC was higher for materials with DCPA-F, except for the 10:40 ratio. DCPA-F resulted in higher strength than DCPA-NF only at 40:10 ratio. Modulus was not affected by functionalization. Materials with similar actual DCPA contents showed differences in DC (F > NF), while no difference in flexural properties was observed between materials with 28%-30% DCPA. Both null hypotheses were rejected.


Assuntos
Cálcio , Fosfatos , Humanos , Resinas Compostas/química , Teste de Materiais , Materiais Dentários , Propriedades de Superfície
14.
Chemosphere ; 310: 136796, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36228722

RESUMO

Increased production and usage of organophosphate esters (OPEs) as flame retardants and plasticizers has trended towards larger and 'novel' (oligomeric) OPEs, although there is a dearth of understanding of the environmental fate, stability, toxicokinetics, biotransformation and bioaccumulation of novel OPEs in exposed biota. The present study characterized in vitro biotransformation of the novel OPE bisphenol-A bis(diphenyl phosphate) (BPADP) using Wistar-Han rat and herring gull liver based microsomal assays. Hypothesized target metabolites bisphenol-A (BPA) and diphenyl phosphate (DPHP) and other metabolites were investigated by applying a lines of evidence approach. In silico modelling predicted both BPA and DPHP as rat metabolites of BPADP, these metabolites were quantified via UHPLC-QQQ-MS/MS. Additional non-target metabolites were determined by UHPLC-Q-Exactive-Orbitrap-HRMS/MS and identified by Compound Discoverer software. Mean BPADP depletion of 44 ± 10% was quantified with 3.9% and 2.6% conversion to BPA and DPHP, respectively, in the rat assay. BPADP metabolism was much slower when compared to the well-studied OPE, triphenyl phosphate (TPHP). BPADP depletion in gull liver assays was far slower relative to the rat. Additional non-target metabolites identified included two Phase I, O-dealkylation products, five Phase I oxidation products and one Phase II glutathione adduct, demonstrating agreement between lines of in vitro and in silico evidence. Lines of evidence suggest that BPADP is biologically persistent in exposed mammals or birds. These findings add to the understanding of BPADP stability and biotransformation, and perhaps of other novel OPEs, which are factors highly applicable to hazard assessments of exposure, persistence and bioaccumulation in biota.


Assuntos
Retardadores de Chama , Fosfatos , Ratos , Animais , Fosfatos/metabolismo , Espectrometria de Massas em Tandem , Ratos Wistar , Organofosfatos/análise , Retardadores de Chama/análise , Biotransformação , Aves/metabolismo , Fígado/metabolismo , Ésteres/análise , Mamíferos/metabolismo
15.
Chemosphere ; 310: 136852, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36241115

RESUMO

Iron (Fe) salt was applied extensively to remove phosphorus (P) in wastewater treatment plants (WWTPs). Exploring the formation mechanism of iron-phosphorus compounds (FePs) during the chemical P removal (CPR) process is beneficial to P recovery. In this study, the performance of P removal, FePs speciation analysis and the kinetics of P removal under different conditions (pH, Fe/P molar ratio (Fe/Pmol), type of Fe salt, dissolved organic matters) were comprehensively investigated. More than 95% of P was removed under the optimal conditions with pH = 4.7, Fe/Pmol = 2, FeCl3 or polymeric ferric sulfate (PFS) as the coagulant. The FePs formation mechanism was considerably influenced by reaction conditions. Iron-phosphate compounds were the dominant FePs species (>76%) at pH < 6.2, while more iron oxides were formed at pH ≥ 6.2 with decreased P removal efficiency. When the initial Fe/Pmol was 2, iron-phosphate compound was the only product that was formed by the reaction between PO43- and Fe(III) or Fe(II) ions directly. More iron oxides were generated when the initial Fe/Pmol was 1 or 3. At Fe/Pmol = 1, the Fe(III) was hydrolyzed to form iron oxides and trapped PO43-, while at Fe/Pmol = 3, iron-phosphate compounds were produced firstly and the remaining Fe(III) was hydrolyzed to form iron oxides. The pseudo-second-order kinetic model simulated the chemical P removal process well. The reaction rate of P with Fe(II) was slower than that with Fe(III), but complete removal was still achieved when the reaction time was more than 30 min. Poly-Fe salt exhibited a fast P removal rate, while the removal efficiency depended on its iron content. Organic matters in wastewater with large molecular weight and multiple functional groups (such as humic acids) inhibited P removal rate but hardly affect the removal amount. This study provides an insight into CPR by Fe salts and is beneficial for P recovery in WWTPs.


Assuntos
Compostos Férricos , Compostos de Ferro , Compostos Férricos/química , Fósforo/química , Ferro/química , Fosfatos , Compostos Ferrosos/química , Óxidos/química
16.
Protein Expr Purif ; 201: 106185, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36195295

RESUMO

In-gel hydrolysis of para-nitrophenyl phosphate (p-NPP) to yellow colored para-nitrophenol was used to locate precisely the K. pneumoniae alkaline phosphatase (Kp-ALKP) on 7% native PAGE. Subsequent removal of the yellow-stained band and electroelution yielded a 54 kDa, Kp-ALKP with Km, Vmax and kcat values of (0.7 ± 0.02) mM, (80 ± 4.5) µmol min-1 and (39.2 ± 2.2) × 104 s-1 respectively for p-NPP. Kp-ALKP was optimally active at 70 °C and pH 7.2 that was activated by Mg2+, Ca2+, Co2+ and inhibited by EDTA, PO4, Pb2+, Cu2+ and Hg2+. The enzyme was trypsin resistant and retained 75% activity in presence of 10 mM PO4 and 65% activity at 3 mM Hg2+ showing it's PO43- irrepressibility and Hg2+-tolerance. Molecular dynamics simulation revealed increased structural stability of Kp-ALKP at 70 °C that accounts for it's optimal temperature. Zymography revealed that both DTT and ß-mercaptoethanol induced activity loss accompanied by mobility retardation of Kp-ALKP on 7% native PAGE. These results and in Silico analysis shows that both DTT and ßME reduce the C308-C358 disulfide bond, leading to an open conformation of the enzyme. However, Hg2+ had negligible effect on the in-gel mobility of Kp-ALKP indicating it's plausible non-covalent interaction with surface-accessible amino-acids without significant conformational change. For the first time our study reveals the zymography as an easy, inexpensive and convenient tool for quick purification, characterization and conformational analysis of K. pneumoniae alkaline phosphatase.


Assuntos
Fosfatase Alcalina , Mercúrio , Fosfatase Alcalina/genética , Dissulfetos , Ácido Edético , Concentração de Íons de Hidrogênio , Cinética , Chumbo , Mercaptoetanol , Nitrofenóis , Fosfatos , Tripsina
17.
J Hazard Mater ; 442: 130106, 2023 01 15.
Artigo em Inglês | MEDLINE | ID: mdl-36209612

RESUMO

Fungus Cladosporium sp. strain F1 showed highly effective biosorption capacity to lead phosphate mineral and perovskite solar cells lead iodide compared to other fungi Aspergillus niger VKMF-1119 and Mucor ramannianus R-56. Scanning electron microscopy and transmission electron microscopy analyses shows that Cladosporium sp. strain F1, which previously showed high biosorption capacity to uranium phosphate nanorods and nanoplates, can accumulate lead phosphate mineral and lead iodide on the fungal hyphae surface in large amounts under a wide range of pH conditions, while A. niger VKMF-1119 and M. ramannianus R-56 adsorbed small amounts of minerals. After biosorption of lead iodide minerals on Cladosporium sp. strain F1, aqueous dimethyl sulfoxide (50%) at pH 2 (70 °C) released the mineral more than 99%. Based on the fungal surface analyses, hydrophobic properties on the surfaces of Cladosporium sp. strain F1 could affect the higher biosorption capacity of strain F1 to lead phosphate mineral and lead iodide as compared to other tested fungi. Cladosporium sp. strain F1 may be the novel biosorbents to remediate the phosphate rich environment and to recover lead from perovskite solar cells lead iodide.


Assuntos
Cladosporium , Urânio , Cladosporium/metabolismo , Adsorção , Fosfatos/metabolismo , Concentração de Íons de Hidrogênio , Biomassa , Iodetos , Urânio/metabolismo , Dimetil Sulfóxido , Chumbo/metabolismo , Aspergillus niger , Minerais/metabolismo
18.
J Colloid Interface Sci ; 629(Pt A): 297-309, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36081209

RESUMO

It is urgent to develop non-noble metal electrocatalysts with both excellent activity and durable stability for H2 production via water electrolysis. Electric energy is mainly consumed by the sluggish anodic oxygen evolution reaction (OER). The electrocatalytic urea oxidation reaction (UOR) has been regarded as a promising reaction to replace OER because of its small thermodynamic oxidation potential. However, developing a facile and large-scale preparation method for bifunctional hydrogen evolution reaction (HER) and UOR electrocatalysts is still challenging. Herein, phosphate-modified (4.46 atomic%) NiMoO4-x net-like nanostructures are formed on Ni foam (NF) via H3PMo12O40 etching strategy at room temperature (denoted as NF/P-NiMoO4-x). The etched NF can directly serve as HER electrode, and delivers overpotential of 116 mV at current density of 10 mA/cm2 with Tafel slope of 77.5 mV/dec. Furthermore, it displays excellent UOR activity with potential of 1.359 V at current density of 10 mA/cm2 and Tafel slope of 19.3 mV/dec. The apparent activation energy of NF/P-NiMoO4-x is 20.6 kJ/mol, lower than that of NF (37.7 kJ/mol), indicating smaller apparent barrier for CN bond cleavage in urea. The cell voltage of urea electrolysis is around 1.48 V for H2 production to deliver current density of 10 mA/cm2, and better long-term stability for 50 h than that of Ir/C||Pt/C. The etching solution can be recycled for five times by addition of H2O2, turning heteropoly blue into its original state. This work develops a facile and large-scale method to prepare bifunctional HER and UOR electrocatalysts for H2 production in a less-energy saving way via urea electrolysis.


Assuntos
Peróxido de Hidrogênio , Fosfatos , Água/química , Hidrogênio , Oxigênio , Ureia , Eletrólise
19.
Sci Total Environ ; 856(Pt 1): 159050, 2023 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-36174683

RESUMO

BACKGROUND: Evidence from in vitro and rodent studies suggests that organophosphate esters (OPEs) may disrupt sex steroid hormone homeostasis, but no human studies, to date, have examined the effects of in utero exposure to OPEs on offspring reproductive development. OBJECTIVE: Anogenital distance (AGD) is a sensitive biomarker of fetal hormonal milieu and has been used to assess reproductive toxicity. We evaluated the longitudinal effects of prenatal exposure to OPEs on the AGD of offspring from birth to 4 years. METHODS: Based on Shanghai-Minhang Birth Cohort Study, pregnant women provided urine samples at a gestational age of 12-16 weeks, which were analyzed for eight OPE metabolites. AGD was measured in offspring at birth and 0.5, 1, and 4 years of age. We used generalized estimating equations (GEE) and Bayesian kernel machine regression (BKMR) models to estimate the associations of prenatal exposure to individual OPE metabolites and OPE mixtures with AGD stratified by sex. RESULTS: A total of 733 mother-infant pairs were analyzed. Prenatal exposure to diphenyl phosphate and bis-(2-ethylhexyl) phosphate was associated with decreased AGD in boys in GEE models. Bis-(1-chloro-2-propyl) phosphate (BCIPP) showed a similar but marginally significant effect. Prenatal exposure to most OPE metabolites was associated with decreased AGD in girls, with the most profound association observed for bis (2-butoxyethyl) phosphate (BBOEP) and alkyl-OPEs. The OPE mixture was also inversely associated with AGD in both sexes. The single-exposure effects of BKMR models were largely consistent with those observed in the GEE models. In addition, alkyl-OPEs, particularly BBOEP, contributed the most to the decreased AGD in girls, while BCIPP contributed the most to the decreased AGD in boys. CONCLUSIONS: This study provides the first human evidence that prenatal exposure to OPEs is associated with decreased AGD in offspring. The magnitude of these effects may vary depending on the structure of OPEs.


Assuntos
Efeitos Tardios da Exposição Pré-Natal , Masculino , Lactente , Recém-Nascido , Humanos , Feminino , Gravidez , Efeitos Tardios da Exposição Pré-Natal/induzido quimicamente , Estudos de Coortes , Teorema de Bayes , China , Organofosfatos/toxicidade , Organofosfatos/urina , Fosfatos
20.
Sci Total Environ ; 856(Pt 1): 159091, 2023 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-36191718

RESUMO

Accurate on-site profiling of the pollutants is of vital significance for estimating environmental pollution. Herein, we propose a paper-based fluorescence-sensing system to precisely report the level of multiple pollutants. A high-performance fluorescence-sensor for apparatus-free and visual on-site tandem precisely reporting phosphate ions (Pi), o-phenylenediamine (OPD), and benzaldehyde (BA) levels have been fabricated successfully by introducing synthesized red emission (>600 nm) fluorescent chromophore 10-(diethylamino)-3-hydroxy-5,6-dihydrobenzo [c]xanthen-12-ium (HTD) into the environment of CoZn zeolitic imidazolate framework (CoZn ZIF) by a simple stirring method. CoZn ZIF@HTD with the bimetallic nodes not merely provided main Zn2+ sites for specific recognition of Pi to generate an enhanced red fluorescent optical signal, Co3+/Co2+ exhibited excellent peroxidase-like activity for the catalytic oxidation of OPD substrate in the presence of H2O2 resulting in color changing from red to yellow. Subsequently, the obvious yellow fading of the OPDox species took place with the addition of BA. By virtue of the sensitively visual tandem detection of Pi, OPD, and BA, the sensor can be applied to real wastewater samples. Meanwhile, this fluorescent sensor was further adopted for practical application in confocal cell imaging and security inks. Overall, this work established a fluorescent sensing system with integrated multifunctional applications for environmental and biological samples, implying the great potential for simultaneous real-time cascade detection of various important pollutants with the merit of low-cost, time-saving, and easy-to-use.


Assuntos
Poluentes Ambientais , Zeolitas , Peróxido de Hidrogênio , Benzaldeídos , Fosfatos
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