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1.
Environ Sci Pollut Res Int ; 31(19): 28241-28252, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38538997

RESUMO

In this study, boron-doped porous carbon materials (BCs) with high surface areas were synthesized employing coffee grounds as carbon source and sodium bicarbonate and boric acid as precursors; afterward, nanoscale zero-valent iron (nZVI) and BCs composites (denoted as nZVI@BCs) were further prepared through reduction of FeSO4 by NaBH4 along with stirring. The performance of the nZVI@BCs for activating persulfate (PS) was evaluated for the degradation of bisphenol A (BPA). In comparison with nZVI@Cs/PS, nZVI@BCs/PS could greatly promote the degradation and mineralization of BPA via both radical and non-radical pathways. On the one hand, electron spin resonance and radical quenching studies represented that •OH, SO4•-, and O2•- were mainly produced in the nZVI@BCs/PS system for BPA degradation. On the other hand, the open circuit voltages of nZVI@BCs and nZVI@Cs in different systems indicated that non-radical pathway still existed in our system. PS could grab the unstable unpaired electron on nZVI@BCs to form a carbon material surface-confined complex ([nZVI@BCs]*) with a high redox potential, then accelerate BPA removal efficiency via direct electron transfer. Furthermore, the performances and mechanisms for BPA degradation were examined by PS activation with nZVI@BC composites at various conditions including dosages of nZVI@BCs, BPA and PS, initially pH value, temperature, common anions, and humid acid. Therefore, this study provides a novel insight for development of high-performance carbon catalysts toward environmental remediation.


Assuntos
Compostos Benzidrílicos , Boro , Carbono , Ferro , Fenóis , Compostos Benzidrílicos/química , Ferro/química , Boro/química , Carbono/química , Fenóis/química , Catálise , Porosidade
2.
Food Chem X ; 20: 100925, 2023 Dec 30.
Artigo em Inglês | MEDLINE | ID: mdl-38144717

RESUMO

Noni fruits have gained considerable popularity as dietary supplements. However, the major constituents, the laxative activity, and the toxicity of Noni fruit remains still unknown. The purpose of the present study was, therefore, to analyze the constituents of methanol extract of Noni fruit by UPLC-MS, and further evaluate laxative activity and safety aspects of this Noni fruit-derived products in mice. UPLC-MS analysis identified eleven major constituents from this Noni fruit extract. Administration of this extract obviously shortened the time of first fecal excrement, significantly increased the total number and the weight of stools, and remarkably restored the intestinal transit to normal level in the constipated mice, with low toxicity to liver and kidney, and meanwhile, the abundance, composition, and function of gut microbiota remained homeostasis. These results revealed the laxative activity of the methanol extract of Noni fruit with low toxicity and no influence on gut microbiota.

3.
Chin Herb Med ; 15(2): 284-290, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-37265760

RESUMO

Objective: In order to distinguish the traditional Chinese medicine Bupleurum falcatum and its adulterants effectively and develop a better understanding of the factors affecting synonymous codon usage, codon usage patterns of chloroplast genome, we determine the complete chloroplast (cp) genome of B. falcatum and clarify the main factors that influence codon usage patterns of 78 genes in B. falcatum chloroplast genome. Methods: The total genomic DNA of fresh leaves from a single individual of B. falcatum was extracted with EASYspin plus Total DNA Isolation Kit and 2 µg genome DNA was sequenced using Illumina Hiseq 2500 Sequencing Platform. The cp genome of B. falcatum was reconstructed with MITObim v1.8 and annotated in the program CPGAVAS2 with default parameters. Python script and Codon W were used to calculate the codon usage bias parameters. Results: The full length of B. falcatum cp genome was 155 851 bp, 132 different genes were annotated in this cp genome containing 80 protein-coding genes, 30 tRNA genes, and four rRNA genes. The codon usage models tended to use A/T-ending codons. The neutrality plot, ENC plot, PR2-Bias plot and correspondence analysis showed that both compositional constraint under selection and mutation could affect the codon usage models in B. falcatum cp genome. Furthermore, three optimal codons were identified and most of these three optimal codons ended with G/U. Conclusion: The cp genome of B. falcatum has been characterized and the codon usage bias in B. falcatum cp genome is influenced by natural selection, mutation pressure and nucleotide composition. The results will provide much more barcode information for species discrimination and lay a foundation for future research on codon optimization of exogenous genes, genetic engineering and molecular evolution in B. falcatum.

4.
Biomed Pharmacother ; 165: 115041, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37356374

RESUMO

Nanoscience has set off a wave in biomedicine to improve the performance of drugs in recent years, but additional materials are usually required for supramolecular nanoconstruction, undoubtedly increasing the health risks. Herein, we discovered a novel diterpene supramolecular self-assembly system without additional chemicals, Nepebracteatalic Acid nanoparticles (NA NPs), mediated through hydrogen bond, hydrophobic and electrostatic interaction. NA NPs performed sustained release behavior, lower expression levels for IL-6 and TNF-α than clinical anti-inflammatory drug Indometacin. Furthermore, the effect of NA NPs on the related protein p65 expression levels of nuclear factor-κB (NFκB) signaling pathway is quantified to confirm the enhanced anti-inflammatory property based on the self-assembly strategy. Meanwhile, the prepared nanoparticles have good biocompatibility which ensures outstanding inflammation inhibition, collagen deposition, angiogenesis during wound healing. This work opens up new prospects that carrier-free nanoparticles from NPMs have great potential to exert clinical application value, meanwhile providing reference for developing green nanoscience.


Assuntos
Diterpenos , Nanopartículas , NF-kappa B/metabolismo , Cicatrização , Nanopartículas/química , Anti-Inflamatórios/farmacologia , Diterpenos/farmacologia
5.
Plant Foods Hum Nutr ; 78(2): 483-492, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37086373

RESUMO

Cucurbitacin IIb (CuIIb) extracted from Hemsleya penxianensis has been demonstrated anticancer activity in many malignancies, however, its effect against bladder cancer cells and the molecular mechanism remains unclear. Accordingly, in the present study, we evaluated the effect and further the underlying mechanism of CuIIb on bladder cancer cells. Cell viability and clonogenicity were examined to evaluate growth suppressive effect of CuIIb, alongside mechanism exploration was conducted based on RNA sequencing (RNA-seq). The results showed that CuIIb exposure inhibited the growth of T24 and UM-UC-3 bladder cancer cells as indicated by its obvious suppression on cell viability and clonogenicity. Mechanistic studies by RNA-seq and quantifying analysis of RNA-seq data by TMNP indicated cell cycle modulated by cell cycle checkpoints and apoptosis mediated by PI3K/Akt pathway might account for the anticancer activity of CuIIb. Consistently, results of flow cytometry and AO/EB staining demonstrated that the growth-suppressive effect of CuIIb was mediated by cell cycle arrest in G2/M phase and robust induction of cell apoptosis, which was further confirmed by immunoblotting and mitochondrial membrane potential (ΔΨm) analysis. Collectively, the results presented herein indicated that CuIIb exhibited anticancer activity on bladder cancer which may be a potential candidate for improving bladder cancer outcomes.


Assuntos
Transdução de Sinais , Neoplasias da Bexiga Urinária , Fosfatidilinositol 3-Quinases/metabolismo , Fosfatidilinositol 3-Quinases/farmacologia , Linhagem Celular Tumoral , Pontos de Checagem do Ciclo Celular , Neoplasias da Bexiga Urinária/tratamento farmacológico , Neoplasias da Bexiga Urinária/patologia , Apoptose , Proliferação de Células
6.
J Hazard Mater ; 443(Pt B): 130386, 2023 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-36444072

RESUMO

The regeneration of Fe(II) is the rate-limiting step in the Fenton/Fenton-like chain reactions that seriously hinder their scientific progress towards practical application. In this study, we proposed iron boride (FeB) for the first time as a new material to sustainably decompose H2O2 to generate hydroxyl radicals, which can non-selectively degrade a wide array of refractory organic pollutants. Fe(II) can be steadily released by the stepwise oxidation of FeB to stimulate Fenton reaction, meanwhile, B-B bonds as electron donors on the surface of FeB effectively promote the regeneration of Fe(II) from Fe(III) species and significantly accelerate the production of hydroxyl radicals. The low generation of toxic by-products and the high utilization rate of iron species validly avoid the secondary organic/metal pollution in the FeB/H2O2 system. Therefore, FeB mediated Fenton oxidation provides a novel strategy to realize a green and long-lasting environmental remediation.

7.
RSC Adv ; 12(34): 21780-21792, 2022 Aug 04.
Artigo em Inglês | MEDLINE | ID: mdl-36043058

RESUMO

Boron-doped carbon materials (BCs), low-cost and environmentally friendly carbocatalysts, were prepared for the activation of persulfate (PS) for the removal of bisphenol A (BPA). Compared with B-free carbon materials (Cs), the adsorption and catalytic activity were significantly enhanced by the boron modification. Fast and efficient removal of BPA was achieved using the BCs/PS system. The BPA removal rate constant increased linearly with the adsorption capacity of BCs. Electron paramagnetic resonance (EPR) spectroscopy and radical quenching experiments indicated that the degradation mechanisms in the BCs/PS system were different from conventional radical-based oxidation pathways. On the contrary, nonradical pathways were demonstrated to dominate the oxidation processes in the removal of BPA using the BCs/PS system. Herein, a mechanism is proposed where PS is activated by the carbon material to form a reactive electron-deficient carbocatalyst ([BCs]*) complex with a high redox potential, driving a nonradical oxidation pathway to achieve BPA removal. Through experimental investigation and the use of electrochemical techniques (cyclic voltammetry, Tafel corrosion analysis and open circuit voltages), B-doped carbon materials for the activation of PS elevate the potential of the derived nonradical [BCs]* complexes, and then accelerate the BPA removal efficiency via an electron transfer process. Utilizing adsorption and nonradical oxidation processes, the BCs/PS system possesses great potential for the removal of BPA in practical applications such as wastewater treatment.

8.
Front Vet Sci ; 9: 930123, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35873677

RESUMO

Porcine parvoviruses (PPV) and porcine circoviruses type 2 (PCV2) are widespread in the pig population. Recently, it was suggested that PPV7 may stimulate PCV2 and PCV3 replication. The present study aimed to make detection and molecular characterization of PPV7 for the first time in eastern Inner Mongolia Autonomous Region, China. Twenty-seven of ninety-four samples (28.72%) and five in eight pig farms were PPV7 positive. Further detection showed that the co-infection rate of PPV7 and PCV2 was 20.21% (19/94), and 9.59% (9/94) for PPV7 and PCV3. In addition, the positive rate of PPV7 in PCV2 positive samples was higher than that in PCV2 negative samples, supporting that PCV2 could act as a co-factor for PPV7 infection. In total, four PPV7 strains were sequenced and designated as NM-14, NM-19, NM-4, and NM-40. The amplified genome sequence of NM-14 and NM-40 were 3,999nt in length, while NM-19 and NM-4 were 3,996nt with a three nucleotides deletion at 3,097-3,099, resulting in an amino acid deletion in the Cap protein. Phylogenetic analysis based on the capsid amino acid (aa) sequences showed that 52 PPV7 strains were divided into two clades, and the four PPV7 strains in this study were all clustered in clade 1. The genome and capsid amino acid sequence of the four PPV7 strains identified in this study shared 80.0-96.9% and 85.9-100% similarity with that of 48 PPV7 reference strains selected in NCBI. Simplot analysis revealed that NM-19 and NM-4 strains were probably produced by recombination of two PPV7 strains from China. The amino acid sequence alignment analysis of capsid revealed that the four PPV7 strains detected in Inner Mongolia had multiple amino acid mutations in the 6 B cell linear epitopes compared with the reference strains, suggesting that the four PPV7 strains may have different characteristics in receptor binding and immunogenicity. In summary, this paper reported the PPV7 infection and molecular characterization in the eastern of Inner Mongolia Autonomous Region for the first time, which is helpful to understand the molecular epidemic characteristics of PPV7.

9.
Cardiovasc Ther ; 2022: 4382999, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35136419

RESUMO

BACKGROUND: Pulmonary arterial hypertension (PAH) usually causes right ventricular dysfunction, which is closely related to cardiac fibrosis. But cardiac fibrosis mechanism remains unclear. Our purpose was to explore microRNA-325-3p (miR-325-3p)/human epididymis protein 4's (HE4) role in the occurrence and development of right ventricular fibrosis in PAH. METHODS: The right ventricular fibrosis model of rats with PAH was constructed, and miR-325-3p was overexpressed to explore miR-325-3p's effect on myocardial fibrosis in rats with PAH. Pearson correlation coefficient examined the correlation between HE4 and miR-325-3p. We separated and identified the primary rat myocardial fibroblasts from the heart tissue. Then, the Ang II-treated myocardial fibroblast fibrosis model was constructed. miR-325-3p mimics and si-HE4 and oe-HE4 cell lines were constructed to investigate miR-325-3p and HE4 effects on myocardial cell fibrosis. Then, we added PI3K inhibitor LY294002 to study the effects of HE4 in cell fibrosis by the PI3K/AKT pathway. Starbase was used to predict miR-325-3p and HE4 binding sites. Dual-luciferase reporter assay verified whether miR-325-3p and HE4 were targeted. RESULTS: Overexpression of miR-325-3p alleviated myocardial fibrosis in rats with PAH. Pearson correlation coefficient showed that HE4 was negatively correlated with miR-325-3p expression. Starbase predicted that miR-325-3p had binding sites with HE4. Dual-luciferase reporter assay demonstrated that miR-325-3p targeted HE4. Overexpression of miR-325-3p downregulated HE4 and inhibited myocardial fibroblast fibrosis. HE4 knockdown inhibited myocardial fibroblast fibrosis. HE4 promoted myocardial fibroblast fibrosis and activated the PI3K/AKT pathway. In addition, HE4 affected myocardial fibroblast fibrosis through the PI3K/AKT pathway. CONCLUSIONS: miR-325-3p could target HE4 to relieve right ventricular fibrosis in rats with PAH. This study could provide new targets and strategies for right ventricular fibrosis in PAH.


Assuntos
MicroRNAs , Hipertensão Arterial Pulmonar , Proteína 2 do Domínio Central WAP de Quatro Dissulfetos/genética , Animais , Fibrose , Humanos , MicroRNAs/genética , Miocárdio/patologia , Fosfatidilinositol 3-Quinases , Ratos
10.
Front Plant Sci ; 12: 769748, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34956269

RESUMO

Nitrogen (N) is one of the most crucial elements for plant growth and development. However, little is known about the metabolic regulation of trees under conditions of N deficiency. In this investigation, gas chromatography-mass spectrometry (GC-MS) was used to determine global changes in metabolites and regulatory pathways in Populus tomentosa. Thirty metabolites were found to be changed significantly under conditions of low-N stress. N deficiency resulted in increased levels of carbohydrates and decreases in amino acids and some alcohols, as well as some secondary metabolites. Furthermore, an RNA-sequencing (RNA-Seq) analysis was performed to characterize the transcriptomic profiles, and 1,662 differentially expressed genes were identified in P. tomentosa. Intriguingly, four pathways related to carbohydrate metabolism were enriched. Genes involved in the gibberellic acid and indole-3-acetic acid pathways were found to be responsive to low-N stress, and the contents of hormones were then validated by high-performance liquid chromatography/electrospray ionization tandem mass spectrometry (HPLC-ESI-MS/MS). Coordinated metabolomics and transcriptomics analysis revealed a pattern of co-expression of five pairs of metabolites and unigenes. Overall, our investigation showed that metabolism directly related to N deficiency was depressed, while some components of energy metabolism were increased. These observations provided insights into the metabolic and molecular mechanisms underlying the interactions of N and carbon in poplar.

11.
Sci Total Environ ; 797: 149097, 2021 Nov 25.
Artigo em Inglês | MEDLINE | ID: mdl-34298366

RESUMO

Slow reduction of Fe(III) in iron-mediated Fenton-like systems strongly limits the decomposition of H2O2 to produce hydroxyl radicals (•OH). Here, we report that graphene oxide (GO) possesses excellent reactivity to enhance the Fe(III)/H2O2 Fenton and photo-Fenton oxidation for degrading chloramphenicol (CAP). EPR analysis and quenching tests reveal that •OH is the primary oxidant for CAP degradation. The characterization analysis and iron species transformation experiments demonstrate that Fe(III) can combine with the functional groups on the GO surface to form GO-Fe(III) complexes. The chronopotentiometry and cyclic voltammogram suggest that GO can donate electrons to Fe(III) via intramolecular electron transfer and promote H2O2 induced Fe(III) reduction by increasing the oxidation capability of Fe(III) due to the formation of GO-Fe(III) complexes, resulting in the strong promotion of the Fe(III)/Fe(II) cycle for producing OH. Moreover, the dark- and vis-GO/Fe(III)/H2O2 systems can effectively degrade CAP at initial pH ranging from 2.0 to 4.7. The reusability and stability of GO were evaluated by performing the cyclic degradation experiments of CAP. The OH induced degradation pathway of CAP was proposed involving three stages, based on intermediates analysis of UPLC-QTOF-MS/MS system. Therefore, the GO/Fe(III)/H2O2 system with or without visible light shows high potential for application in environmental remediation.


Assuntos
Compostos Férricos , Peróxido de Hidrogênio , Cloranfenicol , Grafite , Oxirredução , Espectrometria de Massas em Tandem
12.
J Hazard Mater ; 413: 125304, 2021 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-33626474

RESUMO

In this study, Fenton-like chain reaction is constructed by coupling nanoscale tungsten powders (nW0) and peroxydisulfate (PDS). The nanoscale tungsten powders/peroxydisulfate (nW0/PDS) system exhibits a high oxidation efficiency toward diverse pollutants and expands the effective pH range up to 9.8. Results reveal •OH and sulfate radical (SO4•-) were confirmed to be responsible for 4,4'-ethylidenebisphenol (EBP) degradation, especially •OH. The corrosion process of nW0 results in the in-situ production of H2O2 and the transient-state tungsten species (W (x, x < VI)), initiating the reaction of H2O2 and tungsten species to generate •OH. PDS can accelerate nW0 corrosion to enhance the Fenton-like reaction, and can be activated by tungsten species (nW0 and W (x, x < VI)) to produce •OH and SO4•-. Integrated the analysis results of LC-QTOF-MS/MS, EBP degradation pathways were proposed. This study reveals the high oxidation efficiency over a wide pH range in the nW0/PDS system and provides new insight into the tungsten species induced Fenton-like reaction.

13.
PeerJ ; 9: e10450, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33505783

RESUMO

BACKGROUND: Rheum palmatum is an endangered and important medicinal plant in Asian countries, especially in China. However, there is little knowledge about the codon usage bias for R. palmatum CDSs. In this project, codon usage bias was determined based on the R. palmatum 2,626 predicted CDSs from R. palmatum transcriptome. METHODS: In this study, all codon usage bias parameters and nucleotide compositions were calculated by Python script, Codon W, DNA Star, CUSP of EMBOSS. RESULTS: The average GC and GC3 content are 46.57% and 46.6%, respectively, the results suggested that there exists a little more AT than GC in the R. palmatum genes, and the codon bias of R. palmatum genes preferred to end with A/T. We concluded that the codon bias in R. palmatum was affect by nucleotide composition, mutation pressure, natural selection, gene expression levels, and the mutation pressure is the prominent factor. In addition, we figured out 28 optimal codons and most of them ended with A or U. The project here can offer important information for further studies on enhancing the gene expression using codon optimization in heterogeneous expression system, predicting the genetic and evolutionary mechanisms in R. palmatum.

14.
J Hazard Mater ; 407: 124351, 2021 04 05.
Artigo em Inglês | MEDLINE | ID: mdl-33144019

RESUMO

The specific roles of tartaric acid (TA), as an eco-friendly ligand, in homogeneous and heterogeneous copper-catalyzed systems were systematically revealed and new mechanisms of TA enhancing the three Fenton-like processes were proposed to provide a theoretical significance in overcoming the deficiency of conventional Fenton processes. The results identified hydroxyl radical (•OH) as the main species responsible for the simultaneous decomposition of TA and metronidazole (MNZ) according to TOC removal. The ESR technique was used to detect superoxide radicals (•O2-), carbon-centered radical (•R) and hydrogen radical (•H) in the Cu2+/TA/H2O2 system, which contributed to the acceleration of the Cu2+/Cu+ redox cycle. The enhancing effect of TA on the homogeneous process was ascribed to the formation of a soluble complex with Cu2+, which favored the pH range extension, Cu+ oxidation, and radical generation. Moreover, the adsorption of TA on the catalysts surface promoted the consumption of H2O2, inducing •OH generation. The formed surface complex (≡Cu2+-TA) also accelerated the regeneration of ≡Cu+, which was confirmed by density functional theory (DFT) calculation and surface characterization analysis (SEM, XRD, and XPS). The possible degradation pathways of MNZ in TA-modified Fenton-like system were also clarified.

15.
J Colloid Interface Sci ; 580: 540-549, 2020 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-32711204

RESUMO

The photocatalytic behavior of the graphene oxide (GO) modified Fe(III)/peroxymonosulfate (Fe/PMS) system for bisphenol A (BPA) degradation was investigated. With the addition of GO, a dramatic enhancement of BPA degradation was obtained at pH 3.0 under visible light irradiation. According to ESR analysis and quenching tests, both SO4- and OH are responsible for BPA degradation. The characterization analysis demonstrates that Fe(III) can chelate with the oxygenic functional groups on the surface of GO forming a stable GO-Fe(III) complex. The detections of different kinds of Fe species reveal that Fe(III) can be reduced to Fe(II) by GO via intramolecular electron transfer in the GO-Fe(III) complex, and visible light could enhance this process. The Fe(III)/Fe(II) cycle not only occurs on the surface of GO, but also in aqueous solution via homogeneous reactions. In addition, the degradation pathway of BPA was proposed based on the identification of the intermediates using GC-MS and LC-MS techniques.

16.
Org Lett ; 22(9): 3449-3453, 2020 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-32293190

RESUMO

Two naphthoquinone-derived heterodimers with unprecedented carbon skeletons, eleucanainones A (1) and B (2), were isolated from the bulbs of Eleutherine americana. Their structures were elucidated by comprehensive spectroscopic methods. The structures of 1 and 2 were determined to be the first examples of dibenzofuran- and naphthalenone-containing naphthoquinone dimers. Compound 1 exhibited significant anti-MRSA activity in vitro with minimum inhibitory concentration (MIC) values of 0.78 µg/mL by downregulation of basal expression of agrA, cidA, icaA and sarA in methicillin-resistant S. aureus (MRSA).


Assuntos
Dicetopiperazinas/química , Dicetopiperazinas/farmacologia , Iridaceae/química , Staphylococcus aureus Resistente à Meticilina/efeitos dos fármacos , Antibacterianos/química , Antibacterianos/isolamento & purificação , Antibacterianos/farmacologia , Dicetopiperazinas/isolamento & purificação , Expressão Gênica/efeitos dos fármacos , Staphylococcus aureus Resistente à Meticilina/genética , Staphylococcus aureus Resistente à Meticilina/metabolismo , Testes de Sensibilidade Microbiana , Ressonância Magnética Nuclear Biomolecular , Extratos Vegetais/química , Extratos Vegetais/isolamento & purificação , Extratos Vegetais/farmacologia , Espectrofotometria Ultravioleta
17.
Water Environ Res ; 92(9): 1388-1397, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32281703

RESUMO

A heterogeneous NiO catalyst was prepared by a precipitation process using nickel nitrate with oxalic acid and tested for heterogeneous oxidation of benzoic acid (BA) in the presence of peroxymonosulfate (PMS). It was found that the synthetic NiO is highly effective in heterogeneous activation of PMS to produce sulfate radicals ( SO 4 · - ) and hydroxyl radicals (· OH), and also presents stable performance in the heterogeneous activation of PMS for BA degradation. Physicochemical properties of the NiO catalyst were characterized by several techniques, such as thermogravimetric analysis, Brunauer-Emmett-Teller, Fourier transform infrared spectroscopy, X-ray diffraction, X-ray photoelectron spectroscopy, scanning electron microscopy, and transmission electron microscopy. It was found that NiO and NiOOH were formed on the synthetic NiO catalyst and were stably distributed on the catalyst surface. Nearly 95% decomposition could be achieved in 30 min at the conditions of 500 ml 20 µM BA solution, 0.25 g catalyst, and [PMS]:[BA] = 30:1. The heterogeneous reactions, the effects of PMS concentration, and catalyst dosage on the BA degradation were investigated. The heterogeneous BA degradation reactions followed first-order kinetics. Additionally, quenching experiments proved that the dominant radical in the solution was · OH. The experiments results also showed that this approach is effective for the degradation of many other pollutants (such as tetracycline hydrochloride, 2, 4-dichlorophenol, Acid orange 7, rhodamine B, and methyl red). PRACTITIONER POINTS: A novel NiO material was fabricated for degradation of benzoic acid. The synthetic NiO catalyst comprised active NiO and NiOOH. The main radical for benzoic acid removal rate was · OH. A plausible mechanism for catalyzed degradation of the benzoic acid was proposed.


Assuntos
Ácido Benzoico , Poluentes Químicos da Água , Catálise , Peróxidos , Soluções , Poluentes Químicos da Água/análise
18.
J Hazard Mater ; 391: 122055, 2020 06 05.
Artigo em Inglês | MEDLINE | ID: mdl-32045799

RESUMO

Nitrogen and sulfur-codoped porous carbons (SNCs) with porous structures and high surface areas were successfully synthesized employing coffee grounds, sodium bicarbonate and L-cysteine monohydrochloride as precursors. The SNCs were highly efficient for adsorption and exhibited outstanding catalytic performance for the oxidative degradation of tetracycline hydrochloride (TeC) solutions, especially at a calcined temperature of 700 °C (SNCs-700). The radical quenching, advanced in situ electron paramagnetic resonance (EPR) technology, PS decomposition rates and Linear Sweep Voltammetry (LSV) indicated that the excellent oxidative effectiveness of the PS/SNCs-700 system originated from the nonradical pathways (singlet oxygen (1O2) and electron transfer). It's supposed that N and S doping can effectively create point defects, which could generate 1O2, while carbonyl groups were determined to be the main active sites contributing to the electron transfer. TeC degradation intermediates were also identified, three degradation pathways, revealing that the pre-adsorption significantly accelerated the nonradical oxidation pathways. This approach provides an innovative method for the large-scale production and application of high-quality catalysts in water treatment.

19.
Biomed Pharmacother ; 122: 109354, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31918260

RESUMO

The purpose of the current study was to evaluate the optimal compatibility proportion of 18α-Glycyrrhizic acid (18α-GA) and 18ß-Glycyrrhizic acid (18ß-GA) against carbon tetrachloride (CCl4)-induced hepatic damage in rats, and further explored the underlying mechanism. Rats were injected with CCl4 (0.1%, 0.3 ml/kg) once a week and were orally administrated with different proportions of 18α-, and 18ß-GA daily for 4 weeks. Rats were then sacrificed and blood samples were collected for biochemical assay. Liver tissues were assessed histologically for severity of liver injury. Enzyme activities in liver homogenate were determined using commercial kits. The mRNA levels of associated proteins were evaluated by RT-PCR. The data showed that the combination of 18α-, and 18ß-GA, especially at proportion of 4:6, obviously alleviated CCl4-induced liver injury as evidenced by the improvement of liver histopathological changes, and decreased levels of ALT and AST in serum. Moreover, 18α- and 18ß-GA at all proportions substantially improved glucose tolerance, and markedly reversed the decrease of SOD, MDA, and GSH, and increase of lipid markers (TG, TC, HDL, LDL) induced by CCl4 via regulating the mRNA levels of SREBP-1c, ACC, PPAR-α, and CPT-1a. Collectively, these results suggested that 18α-GA in combination with 18ß-GA, especially at proportion of 4:6, effectively reduced liver injury induced by CCl4, comparable to the positive control silibinin, and the mechanism may be associated with reduced marker of liver oxidative stress and improvement of lipid metabolism via regulation of ACC, CTP-1A, PPARα, and SREBP1.


Assuntos
Tetracloreto de Carbono/farmacologia , Doença Hepática Crônica Induzida por Substâncias e Drogas/tratamento farmacológico , Ácido Glicirrízico/farmacologia , Fígado/efeitos dos fármacos , Acetil-CoA Carboxilase/metabolismo , Animais , Peso Corporal/efeitos dos fármacos , Intoxicação por Tetracloreto de Carbono , Glucose/metabolismo , Teste de Tolerância a Glucose , Glutationa/metabolismo , Lipídeos/sangue , Fígado/patologia , Malondialdeído/metabolismo , Ratos Sprague-Dawley , Proteína de Ligação a Elemento Regulador de Esterol 1/metabolismo , Superóxido Dismutase/metabolismo
20.
RSC Adv ; 10(47): 28232-28242, 2020 Jul 27.
Artigo em Inglês | MEDLINE | ID: mdl-35519150

RESUMO

In this study, four different ZVI/M-PMS systems (e.g., ZVI/Cu, ZVI/Co, ZVI/Ni and ZVI/Ag) were fabricated to investigate the removal of contaminants (Rhodamine B (RB), 2,4-dichlorophenol (2,4-DCP), bisphenol A (BPA), bisphenol F (BPF), levofloxacin (LFX), and chloramphenicol (CAP)). The results indicated that ZVI/Cu and ZVI/Ag exhibited a superior performance to activate PMS compared with the ZVI. The mechanism of the investigation showed that a relatively positive correlation between the release of iron ions (Fe2+) and contaminant removal efficiency was found in different ZVI/M-PMS systems. This revealed that galvanic couples affected iron corrosion, and the ZVI/Cu and ZVI/Ag bimetallic systems facilitated the corrosion of ZVI but the ZVI/Co and ZVI/Ni bimetallic systems restrained the corrosion of ZVI. The electron paramagnetic resonance (EPR) analysis and the radical quenching experiments apparently supported the roles of the hydroxyl radical (˙OH), sulfate radical (SO4˙-) and superoxide radicals (O2˙-), which suggest that these reactive radicals were primarily responsible for the degradative route, and the contribution rate may follow the order of SO4˙- < O2˙- < ˙OH. Furthermore, investigation of crucial parameters showed that the contaminant removal ratio increased with an increase in the metal ratio (M : ZVI) to a certain limit, and a higher bimetal catalyst dosage and extremely acidic conditions (except for ZVI/Co, which showed the best catalytic performance under neutral condition) enhanced the degradation of contaminants. In the evaluation of real water samples, there was almost no influence from the water matrices compared to the control condition, and the ZVI/Cu and ZVI/Ag bimetallic particles showed great potential to treat various wastewater. Therefore, this study helps to understand the application of oxidation process based on bimetallic particles.

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