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1.
Chemphyschem ; 25(6): e202300658, 2024 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-38269420

RESUMO

Synthesising and designing pseudocapacitive material with good electrochemical and electrocatalytic behaviour is essential to use as supercapacitor as well as non-enzymatic glucose sensor electrode. In this work, NiCo2 S4 nanoparticles decorated onto the 2D-Carbyne nanosheets are achieved by the solvothermal process. The as-prepared NiCo2 S4 @2D-Carbyne provides rich reaction sites and better diffusion pathways. On usage as an electrode for supercapacitor application, the NiCo2 S4 @2D-Carbyne exhibits the specific capacitance of about 2507 F g-1 at 1 A g-1 . In addition, the fabricated hybrid device generates an energy density of 52.2 Wh kg-1 at a power density of 1.01 kW kg-1 . Besides, the glucose oxidation behaviour of NiCo2 S4 @2D-Carbyne modified GCE has also been performed. The diffusion of glucose from the electrolyte to the electrode obeys the kinetic control process. Furthermore, the fabricated NiCo2 S4 @2D-Carbyne non-enzymatic glucose sensor exhibits a limit of detection of about 34.5 µM with a sensitivity of about 135 µA mM-1 cm-2 . These findings highlight the need to design and synthesis electrode materials with adequate electrolyte-electrode contact, strong structural integrity, and rapid ion/electron transport.

2.
J Fluoresc ; 2024 Mar 08.
Artigo em Inglês | MEDLINE | ID: mdl-38457074

RESUMO

This study emphasis the solvent effect on third-order nonlinear optical (NLO) features of methyl red (MR) dye dissolved in polar solvents including ethanol, methanol, acetone, 1-propanol, DMF and DMSO using low power diode laser. Z-scan technique operating at 405 nm wavelength, is used to estimate the third-order NLO features of MR dye in various solvents. The dye discloses self-defocusing nonlinear index of refraction (n2), which is determined to be the order of 10-7 cm2/W. The nonlinear coefficient of absorption (ß) of MR dye displays both negative and positive value owing to saturable absorption (SA) and reverse saturable absorption (RSA), respectively. The real and imaginary components of the third-order NLO susceptibility of MR dye in polar solvents are measured to be the order of 10-6 esu and 10-7 esu, respectively. The dye exhibits a large NLO susceptibility in DMSO, which is estimated to be 1.21 × 10-6 esu. The effect of solvent spectral features on MR dye is determined by applying a multi-parameter scale called Kamlet-Abboud-Taft. The experiment results indicate that MR dye is a promising NLO material that may find applications in photonics and optoelectronics.

3.
J Fluoresc ; 2024 Mar 09.
Artigo em Inglês | MEDLINE | ID: mdl-38460094

RESUMO

Herein, we report the nonlinear optical (NLO) refraction and absorption features of azo dye namely, methyl orange (MO) dissolved in ethanol, methanol, acetone, 1-propanol, DMF and DMSO. The UV-Visible absorption study reveals that the maximum absorption spectrum of MO dye appeared towards longer wavelength by increasing the solvent polarizability is the result of red shift or bathochromic shift. The Z-scan method is utilized to measure the third-order NLO features of MO dye in different polar solvents. A continuous wave laser with 5-mW power and an excitation wavelength of 405 nm is employed in the Z-scan technique. The NLO features including nonlinear index of refraction (n2), nonlinear coefficient of absorption (ß) and third-order NLO susceptibility (χ3) are calculated to be the order of 10-7 cm2/W, 10-2 cm/W and 10-7 esu, respectively. The NLO index of refraction shows peak-valley transmittance is the result of self-defocusing and NLO absorption coefficient exhibits both positive and negative nonlinearity owing to saturable absorption (SA) and reverse saturable absorption (RSA). The effect of solvent polarizability and dipole moment on third-order NLO susceptibility of MO dye is discussed. Based on the experimental results, an azo dye MO appears to be a promising option for NLO applications in the future.

4.
Mol Biol Rep ; 51(1): 61, 2024 Jan 03.
Artigo em Inglês | MEDLINE | ID: mdl-38170326

RESUMO

BACKGROUND: Breast adenocarcinoma cells (MCF-7) are characterized by the overexpression of apoptotic marker genes and proliferative cell nuclear antigen (PCNA), which promote cancer cell proliferation. Thymol, derived from Nigella sativa (NS), has been investigated for its potential anti-proliferative and anticancer properties, especially its ability to suppress Cyclin D1 and PCNA expression, which are crucial in the proliferation of cancer cells. METHODS: The cytotoxicity of thymol on MCF-7 cells was assessed using 3-[4,5-dimethylthiazol-2-yl]-2,5 diphenyl tetrazolium bromide (MTT) and lactate dehydrogenase (LDH) release methods. Thymol was tested at increasing concentrations (0-1000 µM) to evaluate its impact on MCF-7 cell growth. Additionally, Cyclin D1 and PCNA gene expression in thymol-treated and vehicle control groups of MCF-7 were quantified using real-time Polymerase Chain Reaction (RT-qPCR). Protein-ligand interactions were also investigated using the CB-Dock2 server. RESULTS: Thymol significantly inhibited MCF-7 cell growth, with a 50% inhibition observed at 200 µM. The gene expression of Cyclin D1 and PCNA was down-regulated in the thymol-treated group relative to the vehicle control. The experimental results were verified through protein-ligand interaction investigations. CONCLUSIONS: Thymol, extracted from NS, demonstrated specific cytotoxic effects on MCF-7 cells by suppressing the expression of Cyclin D1 and PCNA, suggesting its potential as an effective drug for MCF-7. However, additional in vivo research is required to ascertain its efficacy and safety in medical applications.


Assuntos
Neoplasias da Mama , Nigella sativa , Humanos , Feminino , Antígeno Nuclear de Célula em Proliferação/genética , Antígeno Nuclear de Célula em Proliferação/metabolismo , Células MCF-7 , Neoplasias da Mama/genética , Timol/farmacologia , Timol/uso terapêutico , Nigella sativa/metabolismo , Antígenos Nucleares/genética , Antígenos Nucleares/metabolismo , Antígenos Nucleares/uso terapêutico , Ciclina D1/genética , Ciclina D1/metabolismo , Regulação para Baixo , Ligantes , Proliferação de Células
5.
Environ Res ; 258: 119368, 2024 Jun 06.
Artigo em Inglês | MEDLINE | ID: mdl-38848997

RESUMO

The most recent advancement in food packaging research involves improving the shelf life of perishable foods by utilising bio-based resources that are edible, eco-friendly, and biodegradable. The current study investigated the effect of edible pectin coating on mature green tomatoes to improve shelf life and storage properties. Zucchini pectin was used to make edible coating. The antimicrobial and antioxidant properties of extracted pectin were investigated. The findings indicated that the extracted pectin had antimicrobial (Staphylococcus aureus, Escherichia coli, and Aspergillus niger) and antioxidant (34.32% at 1 mg/mL) properties.Tomatoes were immersed in pectin solutions of varying concentrations, 1, 3, and 5% (w/v). Physiological evaluations of weight loss, total sugar content, titratable acidity pH, and ascorbic acid were performed on tomatoes during their maturing stages of mature green, light red, pure red, and breaking. Coating the tomatoes with pectin (5%) resulted in minimal weight loss while increasing the retention of total sugar, ascorbic acid, and titratable acidity. The shelf life of the pectin-coated tomatoes was extended to 11 days, while the uncoated control tomatoes lasted 9 days. Thus, a 5% edible pectin solution was found to be effective in coating tomatoes. The current study suggests that using 5% pectin as an edible coating on tomatoes can delay/slow the ripening/maturing process while also extending the shelf-life of tomatoes without affecting their physiochemical properties, which is scalable on a large scale for commercial purposes.

6.
Environ Res ; 251(Pt 2): 118702, 2024 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-38503381

RESUMO

The anti-inflammatory, anti-diabetic, and biocompatibility nature of Tamarindus indica L. fruit coat aqueous extract were investigated in this research through in-vitro and in-vivo studies. The anti-inflammatory property was determined through albumin denaturation inhibition and antiprotease activities as up to 39.5% and 41.2% respectively at 30 mg mL-1 concentration. Furthermore, the antidiabetic activity was determined through α-amylase and α-glucosidase inhibition as up to 62.15% and 67.35% respectively at 30 mg mL-1 dosage. The albino mice based acute toxicity study was performed by different treatment groups (group I-V) with different dosages of aqueous extract to detect the biocompatibility of sample. Surprisingly, findings revealed that the T. indica L. fruit coat aqueous extract had no harmful impacts on any of the groups. Urine, as well as serum parameter analysis, confirmed this. Moreover, the findings of SOD (Superoxide Dismutase), GST (Glutathione-S-transferase), & CAT (Catalase) as well as glutathione peroxidase as well as reduced glutathione antioxidant enzymes studies stated that the aqueous extract possess high antioxidant ability via a dose-dependent way. These findings indicate that T. indica fruit coat aqueous extract contains medicinally important phytochemicals with anti-inflammatory and anti-diabetic properties, as well as being biocompatible in nature.


Assuntos
Anti-Inflamatórios , Frutas , Hipoglicemiantes , Extratos Vegetais , Tamarindus , Animais , Camundongos , Anti-Inflamatórios/farmacologia , Anti-Inflamatórios/química , Extratos Vegetais/farmacologia , Extratos Vegetais/química , Frutas/química , Tamarindus/química , Hipoglicemiantes/farmacologia , Hipoglicemiantes/química , Masculino , Antioxidantes/farmacologia , Antioxidantes/química , Feminino
7.
Environ Res ; 251(Pt 1): 118632, 2024 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-38467361

RESUMO

Visual impairment due to corneal keratitis-causing bacteria is becoming a matter of health concern. The bacterial colonization and their resistance to multiple drugs need imperative attention. To overcome the issue of alternative remedial therapeutic agents, particularly for topical application, a study was carried out to synthesize calcium oxide nanoparticles (CaO NPs) using the biomaterial Eleusine coracana seed aqueous extract. The biosynthesized calcium oxide nanoparticles (CaO NPs) are non-toxic or less-toxic chemical precursors. Moreover, CaO NPs are eco-friendly and are used for several industrial, biomedical, and environmental applications. Biosynthesized CaO NPs were characterized using ultraviolet-visible spectroscopy, Fourier transform-infrared spectroscopy, scanning electron microscopy, and dynamic light scattering study. The synthesized CaO NPs exhibit with good anti-inflammatory activities with dose dependant (50-250 µg/mL). Moreover, Eleusine coracana-mediated CaO NPs significantly inhibited the multiple drug-resistant Gram-positive Staphylococci epidermidis and Enterococcus faecalis and Gram-negative Escherichia coli and Klebsiella pneumoniae that were isolated from the corneal ulcer. This study provides a potential therapeutic option for multiple drug-resistant corneal pathogens that cause vision impairment.


Assuntos
Antibacterianos , Compostos de Cálcio , Eleusine , Nanopartículas , Extratos Vegetais , Sementes , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Compostos de Cálcio/química , Compostos de Cálcio/farmacologia , Sementes/química , Nanopartículas/química , Antibacterianos/farmacologia , Eleusine/química , Óxidos/química , Óxidos/farmacologia , Farmacorresistência Bacteriana Múltipla/efeitos dos fármacos , Testes de Sensibilidade Microbiana
8.
Environ Res ; 242: 117753, 2024 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-38008204

RESUMO

Polycyclic aromatic hydrocarbons (PAHs) are potentially hazardous compounds that could cause a severe impact on many ecosystems. They are very challenging to remove using conventional methods due to their hydrophobic nature. However, this issue can be resolved by utilizing surface-active molecules to increase their bioavailability. In this study, pyrene was chosen as the PAH compound to explore its degradability by the effect of individual bacterial strains (Pseudomonas stutzeri NA3 and Acinetobacter baumannii MN3) and mixed consortia (MC) along with natural surfactant derived from Sapindus mukorossi and iron oxide nanoparticles (NPs). Additionally, fatty acids esters, dipeptides, and sugar derivative groups were identified as potent bioactive components of natural surfactants. Various techniques, such as XRD, VSM, TEM, and FE-SEM with EDX, were utilized to characterize the pristine and Fenton-treated iron oxide NPs. The analytical results confirmed that the Fe3O4 crystal phase and spherical-shaped NPs exhibited excellent magnetic properties. The impact of natural surfactants and iron oxide NPs has significantly contributed to the biodegradation process, resulting in a prominent decrease in chemical oxygen demand (COD) levels. Gas chromatography-mass spectrometry (GC-MS) analysis showed that biodegradation systems produced primary hydrocarbon intermediates, which underwent oxidative degradation through Fenton treatment. Interestingly, synthesized iron oxide NPs effectively produced hydroxyl radical (•OH) during the Fenton reaction, which was confirmed by electron paramagnetic resonance (EPR) spectra, and the pristine iron oxide NPs underwent a material transformation observed. The study demonstrated an integrated approach for biodegradation and the Fenton reaction process to enhance the pyrene degradation efficiency (90%) compared to other systems. Using natural surfactants and iron oxide NPs in aquatic environments serves as a crucial platform at the interface of microorganisms and contaminated oil products. This interaction offers a promising solution for PAHs bioremediation.


Assuntos
Compostos Férricos , Hidrocarbonetos Policíclicos Aromáticos , Poluentes do Solo , Tensoativos/química , Biodegradação Ambiental , Ecossistema , Poluentes do Solo/análise , Pirenos/metabolismo , Hidrocarbonetos Policíclicos Aromáticos/metabolismo , Bactérias/metabolismo , Nanopartículas Magnéticas de Óxido de Ferro
9.
Environ Res ; 244: 117911, 2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-38104919

RESUMO

Poly aromatic hydrocarbons (PAHs) are considered as hazardous compounds which causes serious threat to the environment dua to their more carcinogenic and mutagenic impacts. In this study, Pseudomonas aeruginosa PP4 strain and synthesized iron nanoparticles were used to evaluate the biodegradation efficiency (BE %) of residual anthracene. The BE (%) of mixed degradation system (Anthracene + PP4+ FeNPs) was obtained about 67 %. The FTIR spectra result revealed the presence of functional groups (C-H, -CH3, CC, =C-H) in the residual anthracene. The FESEM and TEM techniques were used to determine the surface analysis of the synthesized FeNPs and the average size was observed by TEM around 5-50 nm. The crystalline nature of the synthesized iron nanoparticles was confirmed by the observed different respective peaks of XRD pattern. The various functional constituents (OH, C-H, amide I, CH3) were identified in the synthesized iron nanoparticles by FTIR spectrum. In conclusion, this integrated nano-bioremediation approach could be an promising and effective way for many environmental fields like cleanup of hydrocarbon rich environment.


Assuntos
Antracenos , Pseudomonas aeruginosa , Antracenos/metabolismo , Ferro , Biodegradação Ambiental , Nanopartículas Magnéticas de Óxido de Ferro
10.
Environ Geochem Health ; 46(2): 30, 2024 Jan 16.
Artigo em Inglês | MEDLINE | ID: mdl-38227286

RESUMO

The removal of color-causing compounds from wastewater is a significant challenge that industries encounter due to their toxic, carcinogenic, and harmful properties. Despite the extensive research and development of various techniques with the objective of effectively degrading color pollutants, the challenge still persists. This paper introduces a simple technique for producing iron oxide nanoparticles (Fe2O3 NPs) using orange fruit peel for sustainable dye degradation in aqueous environment. The observation of color change and the measurement of UV-visible absorbance at 240 nm provided a confirmation for the development of Fe2O3 NPs. Transmission electron microscopy examination demonstrated that the Fe2O3 NPs have an agglomerated distribution and forming spherical structures with size ranging from 25-80 nm. Energy-dispersive X-ray spectroscopy analysis supported the existence of Fe and O. Fourier transform infrared spectroscopy conducted to investigate the involvement of orange peel extract in the reduction, capping, and synthesis of Fe2O3 NPs from the precursor salt. Fe2O3 NPs showed a photocatalytic remediation of 97%, for methylene blue under visible light irradiation. Additionally, prepared NPs exhibited concentration depended biofilm inhibition action against E. coli and S. aureus. In conclusion, Fe2O3 NPs can efficiently purify water and suppress pathogens due to their strong degrading activity, reusability, and biofilm inhibition property.


Assuntos
Poluentes Ambientais , Águas Residuárias , Escherichia coli , Frutas , Staphylococcus aureus , Nanopartículas Magnéticas de Óxido de Ferro , Extratos Vegetais
11.
Environ Geochem Health ; 46(3): 92, 2024 Feb 17.
Artigo em Inglês | MEDLINE | ID: mdl-38367085

RESUMO

A facile and cost-effective hydrothermal followed by precipitation method is employed to synthesize visible light-driven ZnS-Ag ternary composites supported on carbon aerogel (CA). Extensive studies were conducted on the structural, morphological, and optical properties, confirming the successful formation of ternary nanocomposites. The obtained results evidently demonstrate the successful loading of ZnS and Ag onto the surface of the CA. High-resolution transmission electron microscopy analysis revealed that ZnS and Ag nanoparticles (AgNPs) were uniformly distributed on the surface of the CA with an average diameter of 18 nm. The biomass-derived CA, containing a hierarchical porous nano-architecture and an abundant number of -NH2 functional groups on the surface, can greatly prevent the agglomeration, stability and reduce particle size. Brunauer-Emmett-Teller analysis results indicated specific surface areas of 4.62 m2 g-1 for the CA, 48.50 m2 g-1 for the CA/ZnS composite, and 62.62 m2 g-1 for the CA/ZnS-Ag composite. These values demonstrate an increase in surface area upon the incorporation of ZnS and Ag into the CA matrix. Under visible light irradiation, the synthesized CA/ZnS-Ag composites displayed remarkably improved photodegradation efficiency of methylene blue (MB). Among the tested samples, the CA/ZnS-Ag composites exhibited the highest percentage of photodegradation efficiency, surpassing ZnS, CA, and CA/ZnS. The obtained percentages of degradation efficiency for CA, ZnS, CA/ZnS, and CA/ZnS-Ag composites were determined as 26.60%, 52.12%, 68.39%, and 98.64%, respectively. These results highlight the superior photocatalytic performance of the CA/ZnS-Ag composites in the degradation of MB under visible light conditions. The superior efficiency of the CA/ZnS-Ag composite can be attributed to multiple factors, including its elevated specific surface area, inhibition of electron-hole pair recombination, and enhanced photon absorption within the visible light spectrum. The CA/ZnS-Ag composites displayed consistent efficiency over multiple cycles, confirming their stable performance, reusability, and enduring durability, thereby showcasing the robust nature of this composite material.


Assuntos
Carbono , Nanopartículas Metálicas , Azul de Metileno/química , Prata/química , Nanopartículas Metálicas/química , Biomassa , Luz
12.
Environ Geochem Health ; 46(3): 96, 2024 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-38376605

RESUMO

SrTiO3/Ag nanocomposites were synthesized using a facile wet impregnation method, employing rigorous experimental techniques for comprehensive characterization. XRD, FTIR, UV, PL, FESEM, and HRTEM were meticulously utilized to elucidate their structural, functional, morphological, and optical properties. The electrochemical performance of the SrTiO3/Ag nanocomposite was rigorously assessed, revealing an impressive specific capacitance of 850 F/g at a current density of 1 A. Furthermore, the photocatalytic activity of the SrTiO3/Ag nanocomposite was rigorously examined using methylene blue (MB) dye, and the results were outstanding. After 120 min of UV irradiation, the nanocomposite exhibited an exceptional MB dye degradation efficiency exceeding 88%. The SrTiO3/Ag nanocomposite represents an exemplary catalyst in terms of efficiency, cost-effectiveness, environmental compatibility, and reusability. The electron and superoxide radicals play a chief role in the MB dye degradation process. The inclusion of Ag within the SrTiO3 matrix facilitated the formation of a conductive nano-network, ultimately resulting in superior capacitive and photocatalytic performance.


Assuntos
Poluentes Ambientais , Nanopartículas , Prata , Condutividade Elétrica , Azul de Metileno
13.
Environ Geochem Health ; 46(6): 200, 2024 May 02.
Artigo em Inglês | MEDLINE | ID: mdl-38696110

RESUMO

Plant extracts are a great alternative to synthesizing nanoparticles of different metals and metal oxides. This green synthesis method has opened up numerous possibilities in various scientific domains. In present study, Leaf extract from Vitex negundo is a non-deciduous, long-lasting shrub from the Verbenaceae family is used as capping and reducing agents for the synthesis of silver and palladium nanoparticles. The characterization study UV-vis spectrophotometer analysis showed absorbance value around 320 nm which confirming that Ag-Pd nanoparticles have been successfully obtained. Further, SEM is used to investigate the morphology of Ag-Pd NPs, which revealing their spherical and rod-like configuration, aggregation, and the size of the particles are obtained between 50 and 100 nm. The successful synthesis of Ag-Pd NPs was further confirmed by the EDAX chart, which displayed the peak of Ag and Pd at bending energies between 0.5 and 1.5 keV. According to the quantitative study, Ag and Pd ions found about 5.24 and 13.28%, respectively. In addition, surface studies with TEM confirming that synthesized Ag-Pd NPs are predominates with spheres structure morphologies, with sizes averaging 11.20 nm and ranging from 10 to 20 nm. Further, Ag-Pd nanoparticles was applied as potential photocatalyst materials to degrade methylene blue dye and found about 85% of the degradation efficiency within 150 min of the sunlight exposure thus could be used as catalyst to removal of hazardous organic dye molecules.


Assuntos
Corantes , Nanopartículas Metálicas , Paládio , Prata , Vitex , Vitex/química , Paládio/química , Prata/química , Nanopartículas Metálicas/química , Catálise , Corantes/química , Extratos Vegetais/química , Folhas de Planta/química , Química Verde , Fotólise , Microscopia Eletrônica de Transmissão
14.
Environ Geochem Health ; 46(6): 187, 2024 May 02.
Artigo em Inglês | MEDLINE | ID: mdl-38696018

RESUMO

The presence of toxic trace elements (TEs) has resulted in a worldwide deterioration in freshwater ecosystem quality. This study aimed to analyze the distribution of TEs, including chromium (Cr), nickel (Ni), arsenic (As), mercury (Hg), cadmium (Cd), and lead (Pb), in water, sediment, and organs of Tilapia (Oreochromis mossambicus) collected from selected inland water bodies in Tamil Nadu, India. The water samples exhibited a range of concentrations for TEs: Cr varied from 0.014 to 5.193 µg/L, Ni ranged from 0.283 to 11.133 µg/L, As ranged from 0.503 to 1.519 µg/L, Cd from 0.001 to 0.616 µg/L, and Pb ranged from non-detectable (ND) to 6.103 µg/L. The concentrations of TEs in sediment were found to vary within the following ranges: 5.259 to 32.621 mg/kg for Cr, 1.932 to 30.487 mg/kg for Ni, 0.129 to 0.563 mg/kg for As, 0.003 to 0.011 mg/kg for Cd, ND to 0.003 mg/kg for Hg, and 0.404 to 1.575 mg/kg for Pb. The study found that the accumulation pattern of TE in fishes across all selected areas was liver > bone > gill > muscle. The organs had TE concentrations of Cr (ND-0.769 mg/kg), Ni (ND-1.053 mg/kg), As (0.002-0.080 mg/kg), Pb (ND-0.411 mg/kg), and Hg (ND-0.067 mg/kg), which was below the maximum residual limit prescribed by EC and FSSAI. The bioconcentration factor (BCF) of TEs exhibited a greater magnitude in comparison with the biota-sediment accumulation factor due to the higher concentration of TEs in fish and lower level in water. The assessment of both carcinogenic and non-carcinogenic risks suggests that the consumption of Tilapia from the study region does not pose any significant risks.


Assuntos
Bioacumulação , Sedimentos Geológicos , Tilápia , Oligoelementos , Poluentes Químicos da Água , Animais , Tilápia/metabolismo , Poluentes Químicos da Água/análise , Poluentes Químicos da Água/metabolismo , Medição de Risco , Sedimentos Geológicos/química , Oligoelementos/análise , Oligoelementos/metabolismo , Índia , Monitoramento Ambiental , Metais Pesados/análise , Humanos , Água Doce
15.
Environ Geochem Health ; 46(3): 81, 2024 Feb 17.
Artigo em Inglês | MEDLINE | ID: mdl-38367190

RESUMO

This study presents an environmentally sustainable method for minimizing sludge production in the textile effluent sector through the combined application of electrokinetic (EK) and electrooxidation (EO) processes. AAS and XRF analyses reveal that utilizing acidic electrolytes in the EK method successfully eliminates heavy metals (Cu, Mn, Zn, and Cr) from sludge, demonstrating superior efficiency compared to alkaline conditions. In addition, the total removal efficiency of COD contents was calculated following the order of EK-3 (60%), EK-1 (51%) and EK-2 (34%). Notably, EK-3, leveraging pH gradient fluctuations induced by anolyte in the catholyte reservoir, outperforms other EK systems in removing COD from sludge. The EK process is complemented by the EO process, leading to further degradation of dye and other organic components through the electrochemical generation of hypochlorite (940 ppm). At an alkaline pH of 10.0, the color and COD removal were effectively achieved at 98 and 70% in EO treatment, compared to other mediums. In addition, GC-MS identified N-derivative residues at the end of the EO. This study demonstrates an integrated approach that effectively eliminates heavy metals and COD from textile sludge, combining EK with EO techniques.


Assuntos
Metais Pesados , Esgotos , Esgotos/química , Metais Pesados/análise , Têxteis
16.
Environ Res ; 222: 115370, 2023 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-36716804

RESUMO

Water contamination by reactive dyes is a serious concern for human health and the environment. In this study, we prepared high efficient SnO2/CuO/rGO nanocomposites for reactive dye degradation. For structural analysis of SnO2/CuO/rGO nanocomposites, XRD, UV-Vis DRS, SEM, TEM-EDAX, and XPS analysis were used to characterize the physicochemical properties of the material. The characterization results confirmed great crystallinity, purity, and optical characteristics features. For both Rhodamine B (RhB) and Reactive Red 120 (RR120) degradation processes, SnO2/CuO/rGO nanocomposites were tested for their photocatalytic degradation performance. The SnO2/CuO/rGO nanocomposites have expressed the degradation rate exposed to 99.6% of both RhB and RR120 dyes. The main reason behind the photocatalytic degradation was due to the formation of OH radical's generation by the composite materials. Moreover, the antibacterial properties of synthesized SnO2/CuO/rGO nanocomposites were studied against E. coli, S. aureus, B. subtilis and P. aeroginosa and exhibited good antibacterial activity against the tested bacterial strains. Thus, the synthesized SnO2/CuO/rGO nanocomposites are a promising photocatalyst and antibacterial agent. Furthermore, mechanisms behind the antibacterial effects will be ruled out in near future.


Assuntos
Poluentes Ambientais , Nanocompostos , Humanos , Escherichia coli , Staphylococcus aureus , Corantes/química , Nanocompostos/química , Antibacterianos/farmacologia
17.
Environ Res ; 239(Pt 2): 117387, 2023 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-37832767

RESUMO

In recent years, g-C3N4-Ag nanocomposite synthesis has gained considerable attention for its potential to treat polycyclic aromatic hydrocarbons (PAHs) and to act against bacteria and fungi. In this study, we present a novel approach to the synthesis of g-C3N4-Ag nanocomposite and evaluate its efficiency in both PAH removal and antimicrobial activity. The synthesis process involved the preparation of g-C3N4 by thermal polycondensation of melamine. The factors that affect the adsorption process of PAHs, like time, pH, irradiation type, and adsorbent dosage, were also evaluated. Isotherm models like Langmuir and Freundlich determined the adsorption capability of g-C3N4-Ag. In simulated models, phenanthrene was degraded to a maximum of 85% at lower concentrations of catalyst. The adsorption profile of phenanthrene obeys the pseudo-second-order and Freundlich isotherms pattern. The g-C3N4-Ag nanocomposite also exhibited antimicrobial activity against bacteria (Escherichia coli, Bacillus subtilis, Staphylococcus aureus, Klebsiella pneumoniae) and fungi (Candida albicans). The present study is the first report stating the dual application of g-C3N4-Ag nanocomposite in reducing the concentration of PAH and killing bacterial and fungal pathogens. The higher adsorption capability proclaimed by g-C3N4-Ag nanocomposite shows the fabricated nanomaterial with great potential to remediate organic pollutants from the ecosystem.


Assuntos
Anti-Infecciosos , Poluentes Ambientais , Fenantrenos , Ecossistema , Poluição Ambiental
18.
Environ Res ; 227: 115723, 2023 06 15.
Artigo em Inglês | MEDLINE | ID: mdl-37003548

RESUMO

Three-dimensional multi-porous Iron Oxide/carbon (Fe2O3/C) composites derived from tamarind shell biomass were synthesized by a single-step co-pyrolysis technique and utilized for Paracetamol (PAC) dismissal in the combined adsorption, and advanced oxidation such as electrochemical regeneration techniques. The Fe2O3/C composites were prepared by different pyrolysis temperatures, and named as TS750 (without Fe2O3at 750 °C), MTS450 BCs (Low-450 °C), MTS600 BCs (Moderate-600 °C) and MTS750 BCs (high-750 °C), respectively. As-prepared Fe2O3/C composite was characterized by FE-SEM, XRD, BET, and XPS analysis. The specific surface area and the spatial interaction between the interlayers of Fe2O3 and C were significantly improved by increasing the pyrolysis temperatures from 450 to 750 °C, which improved the adsorption capacity of Fe2O3/C composites in terms of higher rate constants and chemisorption kinetics. The Pseudo-second-order kinetics model fitted in the adsorption test results of Fe2O3/C composites with the highest correlation co-efficiency. The Langmuir-isotherms model fitted in the adsorption test of the TS750 and MTS450 BCs. The Freundlich isotherms model is more fit with MTS600 and MTS750 BCs. Based on the isotherm results, the MTS750 BCs achieved 46.9 mg/g of maximum PAC adsorption capacity. The optimized MTS750 composites could be completely recovered by using an advanced electrochemical oxidation regeneration approach within 180 min. Also, with the adsorption and recovery process, the TOC removal rate improved to ∼79.4%. After the 6th cycle electrochemical oxidation process, the obtained results of the re-adsorption test showed the stabile adsorption activity of the sorbent material. The data outcomes herein propose that this type of combined adsorption and electrochemical approach will be useful in commercial water treatment plants.


Assuntos
Poluentes Químicos da Água , Purificação da Água , Ferro/química , Acetaminofen , Adsorção , Poluentes Químicos da Água/análise , Carbono , Cinética , Purificação da Água/métodos
19.
Molecules ; 28(13)2023 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-37446657

RESUMO

In this study, silver nanoparticles were synthesized using Cucumis melo L. leaf extract via a green synthesis approach and their potential against diabetes and coccidiosis was tested under in vitro conditions. The phytochemical components in the leaf extract reacted with silver nitrate in solution and yielded C. melo-silver nanoparticles (Cm-AgNPs). The synthesis of AgNPs was confirmed via UV-visible spectroscopy by obtaining a peak at 440 nm. The nanoparticles were characterized by their morphology, crystallinity, and the presence of functional groups. In vitro α-amylase and α-glucosidase inhibition assays were carried out at different concentrations in the range of 20 to 100 µg/mL of Cm-AgNPs. The Cm-AgNPs exhibited enzyme inhibitory activity in a concentration-dependent manner. As the concentration of Cm-AgNPs increased the inhibitory activities were also increased linearly and the highest inhibition was observed at 100 µg/mL. The effectiveness of Cm-AgNPs against Eimeria tenalla was assessed by an in vitro 3-(4,5-dimethylthiazolyl-2)-2,5-diphenyltetrazolium bromide (MTT) assay using Madin-Darby bovine kidney (MDBK) cell lines. The results revealed that the viability of the oocysts and further sporulation were decreased with the increased concentration of Cm-AgNPs. The AgNPs synthesized from the C. melo leaf extract have shown promising potential against diabetes and coccidiosis, and they could be used in biomedical applications.


Assuntos
Coccidiose , Cucumis melo , Nanopartículas Metálicas , Animais , Bovinos , Humanos , Nanopartículas Metálicas/química , Hipoglicemiantes/farmacologia , Extratos Vegetais/farmacologia , Extratos Vegetais/química , Prata/farmacologia
20.
Environ Res ; 210: 112833, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-35150712

RESUMO

Sn doped ZnO loaded cotton stalk activated carbon (Sn-ZnO/CSAC) was prepared by chemical precipitation method, and the products were characterized. The XRD resultants confirm that the presence of hexagonal wurtzite phase of the bare ZnO. Furthermore, particular particle size gradually decreases (21.49 nm) due to doping and loading. UV-Vis absorption intensity of doped/loaded sample was red-shifted and then PL intensity is reduced. The photocatalytic performances of bare, Sn-doped ZnO and Sn-ZnO/CSAC was estimated by photodegradation of brilliant green (BG) under sunlight. The photodegradation of BG dye in 120 min over Sn-doped ZnO/CSAC is nearly 96.52%, which is considerably improved than bare ZnO (72.60%), respectively.


Assuntos
Óxido de Zinco , Catálise , Fotólise , Compostos de Amônio Quaternário , Óxido de Zinco/química
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