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1.
Molecules ; 29(19)2024 Oct 09.
Artigo em Inglês | MEDLINE | ID: mdl-39407701

RESUMO

Hexavalent chromium (Cr (VI)) and para-chlorophenol (4-CP) are prevalent industrial wastewater contaminants that are recalcitrant to natural degradation and prone to migration in aquatic systems, thereby harming biological health and destabilizing ecosystems. Consequently, their removal is imperative. Compared to conventional chemical treatment methods, CW-MFC technology offers broader application potential. Leersia hexandra Swartz can enhance Cr (VI) and 4-CP absorption, thereby improving wastewater purification and electricity generation in CW-MFC systems. In this study, three CW-MFC reactors were designed with L. hexandra Swartz in distinct configurations, namely, stacked, multistage, and modular, to optimize the removal of Cr (VI) and 4-CP. By evaluating wastewater purification, electrochemical performance, and plant growth, the optimal influent hydraulic retention time (HRT) was determined. The results indicated that the modular configuration at an HRT of 5 days achieved superior removal rates and power generation. The modular configuration also supported the best growth of L. hexandra, with optimal photosynthetic parameters, and physiological and biochemical responses. These results underscore the potential of modular CW-MFC technology for effective detoxification of complex wastewater mixtures while concurrently generating electricity. Further research could significantly advance wastewater treatment and sustainable energy production, addressing water pollution, restoring aquatic ecosystems, and mitigating the hazards posed by Cr (VI) and 4-CP to water and human health.


Assuntos
Biodegradação Ambiental , Fontes de Energia Bioelétrica , Clorofenóis , Cromo , Águas Residuárias , Poluentes Químicos da Água , Áreas Alagadas , Cromo/química , Clorofenóis/química , Águas Residuárias/química , Purificação da Água/métodos , Eletricidade
2.
Opt Lett ; 48(7): 1638-1641, 2023 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-37221729

RESUMO

Transport-of-intensity diffraction tomography (TIDT) is a recently developed label-free computational microscopy technique that retrieves high-resolution three-dimensional (3D) refractive index (RI) distribution of biological specimens from 3D intensity-only measurements. However, the non-interferometric synthetic aperture in TIDT is generally achieved sequentially through the acquisition of a large number of through-focus intensity stacks captured at different illumination angles, resulting in a very cumbersome and redundant data acquisition process. To this end, we present a parallel implementation of a synthetic aperture in TIDT (PSA-TIDT) with annular illumination. We found that the matched annular illumination provides a mirror-symmetric 3D optical transfer function, indicating the analyticity in the upper half-plane of the complex phase function, which allows for recovery of the 3D RI from a single intensity stack. We experimentally validated PSA-TIDT by conducting high-resolution tomographic imaging of various unlabeled biological samples, including human breast cancer cell lines (MCF-7), human hepatocyte carcinoma cell lines (HepG2), Henrietta Lacks (HeLa) cells, and red blood cells (RBCs).

3.
Ecotoxicol Environ Saf ; 263: 115380, 2023 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-37597293

RESUMO

The roots of hyperaccumulators can significantly alter soil pH and thus change the chromium (Cr) availability in the rhizosphere. The pH dynamics in the rhizosphere of Cr hyperaccumulator Leersia hexandra Swartz remains unknown. In this study, the spatial dynamics of pH in the rhizosphere of L. hexandra at different Cr exposure were examined using planar optode (PO). The effects of different Cr concentrations on the biomass, physiological parameters, and soil enzyme activity were investigated. The results showed that pH in the rhizosphere of L. hexandra was highly heterogeneous and followed the root shape. There were obvious soil acidification in all groups and the average pH values in the control, Cr50, and Cr100 groups decreased by 0.26, 0.27, and 0.35 pH unit, respectively. At a certain concentration (50 mg kg-1), Cr significantly increased the plant height and biomass of L. hexandra compared to the control (p < 0.05). The concentrations of chlorophyll a, chlorophyll b, and total chlorophyll in the leaves increased with increasing Cr concentrations. The acid phosphatase, urease, and catalase activities in the rhizosphere were higher than those in the bulk soil. These results provide new insights into elucidating the hyperaccumulating mechanism of Cr and improving the phytoremediation efficiency.


Assuntos
Poaceae , Rizosfera , Clorofila A , Cromo/toxicidade , Solo , Concentração de Íons de Hidrogênio
4.
Int J Phytoremediation ; 25(10): 1337-1347, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36573355

RESUMO

Cadmium as a heavy metal contaminates the agricultural soil and effect plant growth due to rapid increases in industrialization and anthropogenic activities. Smoke water of Moringa oleifera was used in the current study to alleviate the effect of cadmium on the physiological, biochemical, metabolic, and antioxidant profile of Basmati 385 and Shaheen Basmati seedling. Cadmium stress of 100, 200, and 400 µM were given to 28 days-old seedlings along with smoke water (1:1,000) for one week in hydroponic culture. As a result, Cd+2 toxicity negatively affects the seedling length, fresh and dry weight, photosynthetic pigment, and electrolytes leakage, while the application of smoke water alleviated those effects. Furthermore, Cd+2 content, cell injury, metabolic parameters (proline, total soluble sugar), and antioxidants (peroxidase, catalase) were increased with increasing Cd+2 concentration while smoke water-treated seedlings showed reduction at high concentration. From present study, it can be concluded that smoke water had some regulatory compound which could reduce the Cd+2 stress level in rice seedlings and improve plant growth.


Moringa (Moringa oleifera) is a famous medicinal plant. Its fruits, roots, leaves, and flowers are used as vegetables in different part of the world. Moringa leaves are rich source of vitamin A, C riboflavin, beta carotenoid, iron, and phenolic acid and also reported for antioxidant properties. The unique aspect of current study is use to M. oliferia leaves for the preparation of smoke water, because of its nutritional and antioxidant properties and further its effects was observed on rice seedling under cadmium stress, which has not been evaluated or reported earlier.


Assuntos
Moringa oleifera , Oryza , Antioxidantes/metabolismo , Antioxidantes/farmacologia , Plântula , Cádmio/toxicidade , Cádmio/metabolismo , Moringa oleifera/metabolismo , Fumaça , Biodegradação Ambiental , Água , Raízes de Plantas
5.
Molecules ; 28(8)2023 Apr 08.
Artigo em Inglês | MEDLINE | ID: mdl-37110546

RESUMO

Surfactants are increasingly used in systems that come into contact with the human body, such as food, pharmaceuticals, cosmetics and personal hygiene products. Increasing attention is being devoted to the toxic effects of surfactants in various human contact formulations, as well as the removal of residual surfactants. In the presence of ozone (O3), anion surfactants-a characteristic micro-pollutant-such as sodium dodecylbenzene sulfonate (SDBS) in greywater, can be removed using radical advanced oxidation. Herein, we report a systematic study of the SDBS degradation effect of O3 activated by vacuum ultraviolet (VUV) irradiation and the influence of water composition on VUV/O3, and determined the contribution of radical species. We show a synergistic effect of VUV and O3, while VUV/O3 reached a higher mineralization (50.37%) than that of VUV (10.63%) and O3 (29.60%) alone. The main reactive radicals of VUV/O3 were HO•. VUV/O3 had an optimal pH of 9. The addition of SO42- had almost no effect on the degradation of SDBS by VUV/O3, Cl- and HCO3- slightly reduced the reaction rate, and NO3- had a significant inhibition on the degradation. In total, SDBS had three isomers, with which the three degradation pathways were very comparable. Compared with SDBS, the toxicity and harmfulness of the degradation by-products of the VUV/O3 process decreased. Additionally, VUV/O3 could degrade synthetic anion surfactants from laundry greywater effectively. Overall, the results show the potential of VUV/O3 in safeguarding humans from residual surfactant hazards.

6.
Molecules ; 28(17)2023 Aug 25.
Artigo em Inglês | MEDLINE | ID: mdl-37687068

RESUMO

Efficient and excellent nanoparticles are required for the degradation of organic dyes in photocatalysis. In this study, silver-manganese oxide nanoparticles (Ag-Mn-NPs) were synthesized through a wet chemical precipitation method and characterized as an advanced catalyst that has enhanced photocatalytic activity under sunlight irradiation. The nanoparticles were characterized using scanning electron microscopy (SEM), XRD, UV-vis light spectra, and energy-dispersive X-ray (EDX) spectroscopy, revealing their spherical and agglomerated form. The EDX spectra confirmed the composition of the nanoparticles, indicating their presence in oxide form. These bimetallic oxide nanoparticles were employed as photocatalysts for the degradation of malachite green (MG) dye under sunlight irradiation in an aqueous medium. The study investigated the effects of various parameters, such as irradiation time, catalyst dosage, recovered catalyst dosage, dye concentration, and pH, on the dye's photodegradation. The results showed that Ag-Mn oxide nanoparticles exhibited high photocatalytic activity, degrading 92% of the dye in 100 min. A longer irradiation time led to increased dye degradation. Moreover, a higher catalyst dosage resulted in a higher dye degradation percentage, with 91% degradation achieved using 0.0017 g of the photocatalyst in 60 min. Increasing the pH of the medium also enhanced the dye degradation, with 99% degradation achieved at pH 10 in 60 min. However, the photodegradation rate decreased with increasing dye concentration. The Ag-Mn oxide nanoparticles demonstrate excellent potential as a reliable visible-light-responsive photocatalyst for the efficient degradation of organic pollutants in wastewater treatment.

7.
Environ Geochem Health ; 45(3): 585-606, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-35347514

RESUMO

In order to expound on the present situation and potential risk of road dust heavy metals in major cities, a total of 114 literatures mainly over the past two decades, involving more than 5000 sampling sites in 61 cities of 21 countries, were screened through the collection and analysis of research papers. The concentration, sources, distribution, health risk, sample collection, and analytical methods of heavy metal research on road dust in cities around the world are summarized. The results show that Cd, Zn, and Cu in many urban road dusts in the world are higher than the grade II of the Chinese maximum allowable concentration of potentially toxic elements in the soil. Geo-accumulation index values show that Pb > Cd > Zn > Cu had the highest contamination levels. Hazard index assessment indicates Pb and Cr had the highest potential health risk, especially for children in which ingestion was found as the main exposure pathway. Moreover, through comparative analysis, it is found that some pollutants are higher in developed and industrialized cities and transport (53%) followed by industrial emissions (35%) provide the major contributions to the sources of heavy metals.


Assuntos
Metais Pesados , Poluentes do Solo , Criança , Humanos , Monitoramento Ambiental/métodos , Poeira/análise , Cidades , Cádmio/análise , Chumbo/análise , Poluentes do Solo/toxicidade , Poluentes do Solo/análise , Metais Pesados/toxicidade , Metais Pesados/análise , Medição de Risco/métodos , China
8.
Environ Geochem Health ; 45(5): 1359-1389, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-35972610

RESUMO

Selenium (Se) is an essential metalloid and is categorized as emerging anthropogenic contaminant released to the environment. The rise of Se release into the environment has raised concern about its bioaccumulation, toxicity, and potential to cause serious damages to aquatic and terrestrial ecosystem. Therefore, it is extremely important to monitor Se level in environment on a regular basis. Understanding Se release, anthropogenic sources, and environmental behavior is critical for developing an effective Se containment strategy. The ongoing efforts of Se remediation have mostly emphasized monitoring and remediation as an independent topics of research. However, our paper has integrated both by explaining the attributes of monitoring on effective scale followed by a candid review of widespread technological options available with specific focus on Se removal from environmental media. Another novel approach demonstrated in the article is the presentation of an overwhelming evidence of limitations that various researchers are confronted with to overcome achieving effective remediation. Furthermore, we followed a holistic approach to discuss ways to remediate Se for cleaner environment especially related to introducing weak magnetic field for ZVI reactivity enhancement. We linked this phenomenal process to electrokinetics and presented convincing facts in support of Se remediation, which has led to emerge 'membrane technology', as another viable option for remediation. Hence, an interesting, innovative and future oriented review is presented, which will undoubtedly seek attention from global researchers.


Assuntos
Selênio , Selênio/análise , Ecossistema , Poluição Ambiental
9.
Environ Geochem Health ; 45(3): 1013-1026, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-35635682

RESUMO

The current study features PAHs exposure on Karakoram Highway, a route of utmost importance in Pakistan. The drivers of heavy traffic vehicles (HTV) on Karakoram Highway spend long hours amid dense traffic and therefore, inevitably inhale huge amount of PAH carcinogens. The urinary metabolites of PAHs in such drivers (meeting selection criteria n = 48) and a control group (n = 49) were comparatively profiled. The higher urinary biomarkers among ninety-six percent HTV drivers were evident of PAHs exposure. We observed elevated concentrations of urinary benzo[a]pyrene metabolites (3-OH-BaP = 3.53 ± 0.62 ng g-1 creatinine and 9-OH-BaP = 3.69 ± 0.74 ng g-1 creatinine) in HTV driver's samples compared to controls (0.85 ± 0.08 and 0.31 ± 0.03 ng g-1 creatinine, respectively). Interestingly, urinary benzo[a]pyrene metabolites were detected in almost similar amount among HTV drivers irrespective of their working hours. A distinct smoking effect was manifested with rising urinary levels of 1-hydroxypyrene, 2-hydroxyphenanthrene, and 3-hydroxybenzo[a]pyrene with corresponding increase in driving hours per day. These metabolites exhibited characteristic exposures to low molecular weight volatile PAHs that are commonly found in vehicular exhaust. The elevated PAH body burden was directly linked to the nature of their job and the route-long environmental pollution on Karakoram Highway. Additionally, the poor economic status and smoking also increased HTV driver's health vulnerability and significantly declined their health capacity. There was conclusive evidence that HTV drivers were exposed to PAHs during a ride on Karakoram Highway, back and forth, an aspect not reported earlier.


Assuntos
Exposição Ocupacional , Hidrocarbonetos Policíclicos Aromáticos , Benzo(a)pireno/análise , Exposição Ocupacional/análise , Creatinina , Monitoramento Ambiental/métodos , Hidrocarbonetos Policíclicos Aromáticos/toxicidade , Hidrocarbonetos Policíclicos Aromáticos/urina , Pirenos/metabolismo , Biomarcadores/urina
10.
Vet Med (Praha) ; 68(6): 238-245, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37982002

RESUMO

The present study was aimed at measuring the concentration of aflatoxin M1 (AFM1) in the milk of Holstein Friesian cows, its effect on the milk quality and seasonal trends, as well as to investigate the efficacy of a commercial clay-based toxin binder. For this purpose, milk samples from dairy cows (n = 72) were collected and assayed for AFM1 before employing a clay-based toxin binder. The milk samples (n = 72) were collected from selected animals, revealing that 69.4% of the milk samples had AFM1 levels above the United States permissible limit (0.5 µg/kg). The incidence of AFM1 in milk during the winter and summer was 82.5% and 53.1%, respectively. Owing to the presence of AFM1, the level of milk fat, solids-not-fat, and protein were found to be low. Subsequently, the affected animals were divided into two groups, i.e., AFM1 positive control (n = 10) and the experimental group (n = 40). The experimental group of animals were fed the clay-based toxin binder at 25 g/animal/day. A progressive decrease of 19.8% in the AFM1 levels was observed on day 4 and on day 7 (53.6%) in the treatment group. Furthermore, the fat, solids-non-fat and protein increased significantly in the milk. In conclusion, a high level of AFM1 contamination occurs in the milk in Pakistan, affecting the quality of the milk production. Clay-based toxin binders may be used to ensure the milk quality and to protect the animal and consumer health.

11.
Vet Med (Praha) ; 68(10): 385-391, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-38028205

RESUMO

Enzootic bovine leucosis is caused by bovine leukaemia virus (BLV), a Deltaretrovirus belonging to the family Retroviridae. BLV causes huge economic losses to the dairy industry in the form of decreased milk production, premature culling, and poor reproductive performance of the animals. The aim of the present study was to determine the seroprevalence of BLV infection in buffalo in two districts of Punjab, Pakistan. A total of 384 samples were collected and analysed using a commercial indirect enzyme-linked immunosorbent assay (ELISA) to investigate the seroprevalence of BLV through the detection of the anti-BLV gp51 antibody. A predesigned data questionnaire proforma was employed to find out the association of risk factors with disease. Overall, 18.2% of buffaloes were seropositive for BLV in the study population. The results revealed a significant association (P < 0.05) of age with BLV infection. Furthermore, milk yield and pregnancy had a significant association with the seroprevalence of BLV infection in buffalo whereas no significant association was found with sex, breeding, and health status. Biochemical and oxidative stress markers revealed a significant decrease in liver enzymes alanine transaminase (ALT) and aspartate transaminase (AST), glutathione peroxidase (GPX), and superoxide dismutase (SOD) in seropositive animals as compared to healthy animals. It is concluded that BLV has a considerable prevalence in buffalo in Punjab, Pakistan and there is a dire need to investigate the disease epidemiology at both national and international levels and strategies should be developed to implement an effective control program.

12.
Microb Pathog ; 171: 105739, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-36055570

RESUMO

Gut microbial dysbiosis during the development of Hepatitis C virus and liver-related diseases is not well studied. Nowadays, HCV and liver cirrhosis are the major concerns that cause gut bacterial alteration, which leads to dysbiosis. For this purpose, the present study was aimed at correlating the gut bacterial community of the control group in comparison to HCV and liver cirrhotic patients. A total of 23 stool samples were collected, including control (9), liver cirrhotic (8), and HCV (6). The collected samples were subjected to 16 S rRNA Illumina gene sequencing. In comparison with control, a significant gut bacterial alteration was observed in the progression of HCV and liver cirrhosis. Overall, Firmicutes were significantly abundant in the whole study. No significant difference was observed in the alpha diversity of the control and patient studies. Additionally, the beta diversity based on non-metric multidimensional scaling (NMDS) has a significant difference (p = 0.005) (ANOSIM R2 = 0.14) in all groups. The discriminative results based on the LEfSe tool revealed that the HCV-infected patients had higher Enterobacteriaceae and Enterobacterial, as well as Lactobacillus and Bacilli in comparison than the liver-cirrhotic patients. These taxa were significantly different from the control group (p < 0.05). Regarding prospects, a detailed analysis of the function through metagenomics and transcriptomics is needed.


Assuntos
Microbioma Gastrointestinal , Hepatite C , Hepatopatias , Bactérias/genética , Disbiose/microbiologia , Enterobacteriaceae/genética , Hepacivirus/genética , Hepatite C/complicações , Humanos , Cirrose Hepática , Projetos Piloto , RNA Ribossômico 16S/genética
13.
Molecules ; 27(15)2022 Jul 25.
Artigo em Inglês | MEDLINE | ID: mdl-35897930

RESUMO

Epilepsy is a neurological disorder involving persistent spontaneous seizures and uncontrolled neuronal excitability that leads to cognitive impairments and blood-brain barrier (BBB) disruption. Currently available antiepileptic drugs present side effects and researchers are trying to discover new agents with properties to overcome these drawbacks. The aim was to synthesize magnesium oxide (MgO) and zinc oxide (ZnO) nanoparticles from Datura alba fresh leaf extracts and evaluate their anti-epileptic potential in mice kindling or a repetitive seizures model. The phytoassisted synthesized nanoparticles were characterized using spectroscopy; FT-IR, XRD, SEM, and EDX. Analysis of the NPs confirmed the crystalline pleomorphic shape using the salts of both zinc and magnesium possibly stabilized, functionalized and reduced by bioactive molecules present in plant extract. By using several characterization techniques, NPs were confirmed. UV-Vis spectroscopy of biologically produced ZnO and MgO revealed distinctive peaks at 380 nm and 242 nm, respectively. Our findings categorically demonstrated the reductive role of biomolecules in the formation of ZnO and MgO NPs. The mice kindling model was induced using seven injections of Pentylenetetrazole (PTZ, 40 mg/kg, i.p) for 15 days alternatively. The results showed that mice post-treated with either ZnO or MgO nanoparticles (10 mg/kg, i.p) significantly improved in respect of behavior and memory as confirmed in the Morris water maze (MWM), open field (OF), novel object recognition (NOR) test compared with PTZ treated mice. Furthermore, the ZnO and MgO nanoparticle treatment also maintained the integrity of the BBB, reducing the leakage, as confirmed by Evans blue dye (EBD) compared with PTZ treated mice only. In summary, the current finding demonstrates that green synthesized ZnO and MgO nanoparticles have neuroprotective, ant-epileptic potential, molecular mechanisms, and clinical implications need to be further explored.


Assuntos
Disfunção Cognitiva , Datura , Nanopartículas Metálicas , Nanopartículas , Óxido de Zinco , Animais , Antibacterianos/farmacologia , Barreira Hematoencefálica , Disfunção Cognitiva/tratamento farmacológico , Magnésio/farmacologia , Óxido de Magnésio/farmacologia , Nanopartículas Metálicas/química , Camundongos , Nanopartículas/química , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Convulsões/induzido quimicamente , Convulsões/tratamento farmacológico , Espectroscopia de Infravermelho com Transformada de Fourier , Óxido de Zinco/química , Óxido de Zinco/farmacologia
14.
Molecules ; 27(15)2022 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-35956859

RESUMO

Due to their unique layered microstructure, the presence of various functional groups at the surface, earth abundance, and attractive electrical, optical, and thermal properties, MXenes are considered promising candidates for the solution of energy- and environmental-related problems. It is seen that the energy conversion and storage capacity of MXenes can be enhanced by changing the material dimensions, chemical composition, structure, and surface chemistry. Hence, it is also essential to understand how one can easily improve the structure-property relationship from an applied point of view. In the current review, we reviewed the fabrication, properties, and potential applications of MXenes. In addition, various properties of MXenes such as structural, optical, electrical, thermal, chemical, and mechanical have been discussed. Furthermore, the potential applications of MXenes in the areas of photocatalysis, electrocatalysis, nitrogen fixation, gas sensing, cancer therapy, and supercapacitors have also been outlooked. Based on the reported works, it could easily be observed that the properties and applications of MXenes can be further enhanced by applying various modification and functionalization approaches. This review also emphasizes the recent developments and future perspectives of MXenes-based composite materials, which will greatly help scientists working in the fields of academia and material science.

15.
Chem Rec ; 21(7): 1811-1844, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-33887089

RESUMO

Recently, polymeric carbon nitride (g-C3 N4 ) as a proficient photo-catalyst has been effectively employed in photocatalysis for energy conversion, storage, and pollutants degradation due to its low cost, robustness, and environmentally friendly nature. The critical review summarized the recent development, fundamentals, nanostructures design, advantages, and challenges of g-C3 N4 (CN), as potential future photoactive material. The review also discusses the latest information on the improvement of CN-based heterojunctions including Type-II, Z-scheme, metal/CN Schottky junctions, noble metal@CN, graphene@CN, carbon nanotubes (CNTs)@CN, metal-organic frameworks (MOFs)/CN, layered double hydroxides (LDH)/CN heterojunctions and CN-based heterostructures for H2 production from H2 O, CO2 conversion and pollutants degradation in detail. The optical absorption, electronic behavior, charge separation and transfer, and bandgap alignment of CN-based heterojunctions are discussed elaborately. The correlations between CN-based heterostructures and photocatalytic activities are described excessively. Besides, the prospects of CN-based heterostructures for energy production, storage, and pollutants degradation are discussed.

16.
Ecotoxicol Environ Saf ; 221: 112426, 2021 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-34166940

RESUMO

Lead (Pb) and cadmium (Cd) are considered as a typical heavy metals in aqueous solution, which may pose adverse health effects on human beings. For the removal of these two pollutants, magnesium oxide (MgO) was successfully immobilized onto eucalyptus biochar (BC) matrix via simple and cost-effective pyrolysis process of MgCl2-pretreated eucalyptus biomass under high temperature (500 °C). Synthesized MgO nanoparticles-biochar composites (MBC) exhibited superior removal performance for target pollutants, and achieve 99.9% removal efficiency for Pb(II) and Cd(II) at optimum conditions (0.02 g, pH in range of 4-7, and reaction time 120, 240 min). Furthermore, the maximum theoretical adsorbing amount of MBC was 829.11 mg/g for Pb(II) and 515.17 mg/g for Cd(II). Pseudo-second-order model and Langmuir models were well-determined for isotherm and adsorption kinetics. FTIR, XRD, and XPS analysis revealed that precipitation and ion exchange was of great importance for the removal of contaminants. Besides, cation-π interaction and complexation from the carbon-containing functional groups should not be neglected. Considering the advantage of low-cost, facile preparation, and brilliant adsorption capacity, it is anticipated that MBC has a promising prospect for the broad application in Pb(II)/Cd(II)-containing wastewater treatment.


Assuntos
Cádmio/química , Carvão Vegetal/química , Eucalyptus , Chumbo/química , Óxido de Magnésio/química , Poluentes Químicos da Água/química , Purificação da Água/métodos , Adsorção , Soluções
17.
Environ Sci Technol ; 54(4): 2476-2488, 2020 02 18.
Artigo em Inglês | MEDLINE | ID: mdl-31971792

RESUMO

Nonradical-based advanced oxidation processes for pollutant removal have attracted much attention due to their inherent advantages. Herein we report that magnesium oxides (MgO) in CuOMgO/Fe3O4 not only enhanced the catalytic properties but also switched the free radical peroxymonosulfate (PMS)-activated process into the 1O2 based nonradical process. CuOMgO/Fe3O4 catalyst exhibited consistent performance in a wide pH range from 5.0 to 10.0, and the degradation kinetics were not inhibited by the common free radical scavengers, anions, or natural organic matter. Quantitative structure-activity relationships (QSARs) revealed the relationship between the degradation rate constant of 14 substituted phenols and their conventional descriptor variables (i.e., Hammett constants σ, σ-, σ+), half-wave oxidation potential (E1/2), and pKa values. QSARs together with the kinetic isotopic effect (KIE) recognized the electron transfer as the dominant oxidation process. Characterizations and DFT calculation indicated that the incorporated MgO alters the copper sites to highly oxidized metal centers, offering a more suitable platform for PMS to generate metastable copper intermediates. These highly oxidized metals centers of copper played the key role in producing O2•- after accepting an electron from another PMS molecule, and finally 1O2 as sole reactive species was generated from the direct oxidation of O2•- through thermodynamically feasible reactions.


Assuntos
Óxido de Magnésio , Peróxidos , Transporte de Elétrons , Cinética , Metais , Oxirredução
18.
Phytopathology ; 110(3): 582-592, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31799901

RESUMO

Fusarium root and crown rot is the most common disease of wheat, especially wheat grown in arid zones where drought is a common issue. The development of environmentally safe approaches to manage diseases of food crops is important for humans. The monocropping system recruits beneficial bacteria that promote plant growth through nutrient solubilization and pathogen suppression. In this study, a field where wheat was monocropped for 5 successive years under rainfed conditions was identified. A total of 29 bacterial isolates were obtained from the rhizosphere, endosphere, and phyllosphere of wheat at its harvesting stage. The Gram-negative bacteria were less prevalent (41%) but the majority (75%) exhibited plant growth-promoting traits. The ability of strains to solubilize nutrients (solubilization index = 2.3 to 4), inhibit pathogenic fungi (25 to 56%), and produce antifungal compounds was highly variable. The rhizobacteria significantly promoted the growth and disease resistance of wheat varieties such as Pirsbak-2015 and Galaxy-2013 by inducing antioxidant enzyme activity (0.2- to 2.1-fold). The bacterial strains were identified as Ochrobactrum spp., Acinetobacter spp., and Pseudomonas mediterranea by 16S rRNA and rpoD sequence analysis. The endophytic bacterium P. mediterranea HU-9 exhibited maximum biocontrol efficacy against wheat root and crown rot diseases with a disease score/disease index from 1.8 to 3.1. The monocropping systems of rainfed agriculture are an ideal source of beneficial bacteria to use as bioinoculants for different crops.


Assuntos
Fusarium , Doenças das Plantas , Raízes de Plantas , Pseudomonas , RNA Ribossômico 16S , Triticum
19.
Ecotoxicol Environ Saf ; 187: 109845, 2020 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-31654865

RESUMO

The extensive use of nano-fabricated products in daily life is releasing a large volume of engineered nanoparticles (ENPs) in the environment having unknown consequences. Meanwhile, little efforts have been paid to immobilize and prevent the entry of these emerging contaminants in the food chain through plant uptake. Herein, we investigated the biochar role in cerium oxide nanoparticles (CeO2NPs) bioaccumulation and subsequent translocation in wheat (Triticum aestivum L.) as well as impact on growth, photosynthesis and gas-exchange related physiological parameters. Results indicated that CeO2NPs up to 500 mg L-1 level promoted the plant growth by triggering photosynthesis, transpiration and stomatal conductance. Higher NPs concentration (2000 mg CeO2NPs L-1) has negatively affected the plant growth and photosynthesis related processes. Conversely, biochar amendment with CeO2NPs considerably reduced (~9 folds) the plants accumulated contents of Ce even at 2000 mg L-1 exposure level of CeO2NPs through surface complexation process and alleviated the phyto-toxic effects of NPs on plant growth. XPS and FTIR analysis confirmed the role of biochar-mediated carboxylate and hydroxyl groups bonding with CeO2NPs. These findings provides an inside mechanistic understanding about biochar interaction with nano-pollutants to inhibit their bioavailability to plant body.


Assuntos
Cério/análise , Carvão Vegetal/química , Nanopartículas/análise , Fotossíntese/efeitos dos fármacos , Poluentes do Solo/análise , Triticum/efeitos dos fármacos , Disponibilidade Biológica , Cério/metabolismo , Recuperação e Remediação Ambiental/métodos , Nanopartículas/metabolismo , Solo/química , Poluentes do Solo/metabolismo , Triticum/metabolismo
20.
BMC Complement Altern Med ; 19(1): 296, 2019 Nov 06.
Artigo em Inglês | MEDLINE | ID: mdl-31694704

RESUMO

BACKGROUND: Bergenia ciliata is a medicinal plant used for the treatment of diarrhea, vomiting, fever, cough, diabetes, cancer, pulmonary disorders and wound healing. METHODS: In this study, Bergenia ciliata crude extract, subfractions, and isolated compounds were evaluated for their antioxidant and anticholinesterase potential. The free radical scavenging capacities of the extracts determined using DPPH and ABTS assays. The anticholinesterase potentials were determined using acetylcholine esterase and butyryl choline esterase enzymes. To determine the phytochemical composition, the extracts were subjected to HPLC analysis and silica gel column isolation. Based on HPLC fingerprinting results, the ethyl acetate fraction was found to have more bioactive compounds and was therefore subjected to silica gel column isolation. As a result, three compounds; pyrogallol, rutin, and morin were isolated in the pure state. The structures of the isolated compounds were elucidated using spectroscopic techniques like 1H-NMR, IR and UV-Visible. RESULTS: The crude extract showed maximum anticholinesterase (acetylcholinesterase = 90.22 ± 1.15% and butyrylcholinesterase = 88.22 ± 0.71%) and free radical scavenging (87.37 ± 2.45 and 83.50 ± 0.70% respectively against DPPH and ABTS radicals) potentials. The total phenolic contents (expressed as equivalent of gallic acid; mgGAE/g) were higher in ethyl acetate fraction (80.96 ± 1.74) followed by crude extract (70.65 ± 0.86) while the flavonoid contents (expressed as quercetin equivalent; mgQE/g) and were higher in crude extract (88.40 ± 1.12) followed by n-butanol fraction (60.10 ± 1.86). The isolated bioactive compounds pyrogallol, rutin, and morin were found active against ABTS and DPPH free radicals. Amongst them, pyrogallol was more active against both free radicals. Reasonable anticholinesterase activities were recorded for pyrogallol against selected enzymes. CONCLUSION: The extracts and isolated compounds showed antioxidant and acetylcholinesterase inhibitory potentials. It was concluded that this plant could be helpful in the treatment of oxidative stress and neurological disorders if used in the form of extracts.


Assuntos
Antioxidantes/química , Inibidores da Colinesterase/química , Extratos Vegetais/química , Saxifragaceae/química , Acetilcolinesterase/química , Antioxidantes/isolamento & purificação , Butirilcolinesterase/química , Inibidores da Colinesterase/isolamento & purificação , Flavonoides/química , Flavonoides/isolamento & purificação , Fenóis/química , Fenóis/isolamento & purificação , Extratos Vegetais/isolamento & purificação , Rizoma/química
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