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1.
Front Microbiol ; 15: 1458369, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39380679

RESUMO

Background: Environmental soil contamination is a serious problem for humans worldwide, as it causes many diseases. Methods: The present study focuses on utilizing biosurfactants produced by Pseudomonas stutzeri (P. stutzeri) NA3 and Bacillus cereus (B. cereus) EN6, as an electrolyte for removing chromium (Cr) from contaminated soil using the electrokinetic (EK) process. Results: As a result, biosurfactants produced by P. stutzeri NA3 and B. cereus EN6, being lipopeptides, increase heavy metal mobility in the EK process. The Cr removal efficiency of a novel electrolyte (biosurfactants) in the EK process was compared with that of NA3 and EN6 biosurfactants. The EK results revealed a maximum Cr removal of 75 and 70% by NA3 and EN6, respectively, at the end of 7 days. Discussion: The biosurfactant aids in the breaking down of the heavy metals that are present deeper into the soil matrix. From the metagenomics analysis, it was identified that biosurfactant changes the microbial community with an enhanced ability to remove heavy metals. The phytotoxicity assay confirms that NA3 biosurfactant solution showed 95% seed germination and can lower hazardous pollutants in the soil. Conclusion: The application of biosurfactants as a potent electrolyte for the remediation of hazardous pollutants is an integrated process. Overall, the results of this study suggest that biosurfactants can serve as an economic and efficient electrolyte in the EK process to remove Cr from polluted soil.

2.
Luminescence ; 39(10): e4915, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-39370760

RESUMO

Lanthanum oxide was successfully synthesized by hydrothermal method by varying the reaction time such as 6, 12, and 24 h. In XRD, study confirms the presence of a hexagonal structure, and the phase remains the same at different times; the main goal is to assess the average crystallite size of prepared La2O3 nanoparticles, which was found in the range of 6 to 8 nm. An interesting observation from the XRD data was the apparent increase in crystalline nature as the synthesis time was extended. The UV-Vis spectroscopic studies show a change in the band gap when the reaction time is changed. The morphology analysis shows that the image revealed that the particles formed were agglomerated and formed a spherical shape, with diameters ranging between 35 and 86 nm. When tested for photocatalytic activity, the La2O3 nanoparticles show a degradation of methylene blue dye when the time varies. Remarkably, the nanoparticles synthesized exhibited a profound ability to degrade the dye, with an efficiency rate hitting as high as 89% under halogen light illumination.


Assuntos
Corantes , Lantânio , Óxidos , Lantânio/química , Catálise , Óxidos/química , Corantes/química , Corantes/síntese química , Tamanho da Partícula , Nanopartículas/química , Azul de Metileno/química , Fatores de Tempo , Propriedades de Superfície
3.
Sci Rep ; 14(1): 25408, 2024 10 25.
Artigo em Inglês | MEDLINE | ID: mdl-39455801

RESUMO

This study investigates the efficacy of newly synthesized inhibitor with a dual function of corrosion inhibition and biocide for control of microbial influenced corrosion (MIC) in carbon steel API 5LX in the cooling tower water (CTW) environment. Four types of N-substituted tetrabromophthalic inhibitor (N-TBI) were synthesized, and the structural characterization was performed via proton nuclear magnetic resonance spectroscopy, thermogravimetric analysis and high-resolution mass spectrometry. These studies revealed the distinctive optical, thermal, and dielectric properties of the synthesized inhibitors. The corrosion inhibition efficiency has been evaluated by the weight loss (WL) analysis and electrochemical measurements (ECM) and biofilm assay. Biofilm assays and WL showed that inhibitor II exhibited the highest inhibition efficiency 74% and 79% respectively than others. Further ECM showed that the higher charge transfer resistance and the lower corrosion current, suggesting a protective film formed on the metal surface which was due to the adsorption of the N-TBI. Fourier transform infrared spectroscopy confirmed the adsorption of the N-TBI as C-O stretching and C-H bending with the Fe complex. X-ray diffractometer revealed that the presence of inhibitors in the corrosion product (Fe3O4, Fe2O3, FeH2O2, FeS) were highly reduced than the control system. Overall, this study highlighted the potential application of N-TBI with dual function of corrosion inhibition and biocide to control the MIC for carbon steel API 5LX used in the CTW environment.


Assuntos
Ácidos Ftálicos , Aço , Corrosão , Ácidos Ftálicos/química , Ácidos Ftálicos/farmacologia , Aço/química , Água/química , Biofilmes/efeitos dos fármacos , Biofilmes/crescimento & desenvolvimento , Espectroscopia de Infravermelho com Transformada de Fourier
4.
Luminescence ; 39(10): e4927, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-39428725

RESUMO

The focus of current advances in nanotechnology has shifted significantly towards environmentally conscious methods that use harmless ingredients and moderated reaction circumstances to promote equitable development. Zinc oxide nanoparticles (NPs) currently grabbed attention of multiple medical fields owing to their unique ability to safeguard against cellular damage and alleviate serious human diseases via processes related to metabolism. This work focused on the generation of ZnO NPs using the peel of Cucumis melo fruit. The NPs were then analyzed and characterized using UV-Vis spectroscopy. The results indicated that at a wavelength of 352 nm, it was proven that the biosynthesis of ZnO NPs had occurred. The XRD pattern indicated the presence of dense crystal structures. The field emission scanning electron microscope (FE-SEM) picture confirmed the existence of polygonal-shaped ZnO NPs. The findings indicate that the produced ZnO NPs possess tough antibacterial properties against Gram-positive and Gram-negative microorganisms. When the ZnO NPs were exposed to direct sunshine for 80 min, they showed an 89% dye breakdown efficiency. This research specifically focused on the decomposition of reactivity dyes, with methylene blue dye being used as the target dye. The work demonstrates that the biosynthesis of ZnO NPs has a crucial and versatile role in the biological and environmental sectors.


Assuntos
Antibacterianos , Cucumis melo , Frutas , Extratos Vegetais , Óxido de Zinco , Óxido de Zinco/química , Óxido de Zinco/farmacologia , Cucumis melo/química , Catálise , Frutas/química , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Antibacterianos/farmacologia , Antibacterianos/química , Testes de Sensibilidade Microbiana , Nanopartículas Metálicas/química , Luminescência , Processos Fotoquímicos , Azul de Metileno/química , Azul de Metileno/farmacologia , Tamanho da Partícula , Substâncias Luminescentes/química , Substâncias Luminescentes/farmacologia , Substâncias Luminescentes/síntese química , Bactérias Gram-Positivas/efeitos dos fármacos , Bactérias Gram-Negativas/efeitos dos fármacos , Nanopartículas/química
5.
Environ Sci Pollut Res Int ; 31(43): 55562-55576, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-39235759

RESUMO

The current investigation focused on the green synthesis of silver nanoparticles (Ag NPs) using Malachra alceifolia (Ma) (the common name is wild okra) leaf extract. The morphological, structural, and optical properties of the synthesized Ma-Ag NPs were characterized by various techniques. The absorption spectral studies (UV-vis and FTIR) confirm the formation of Ma-Ag NPs and their band gap was calculated as 2.1 eV with the help of Tauc's equation. The XRD study gives information about the crystalline nature and FCC structure. The SEM analysis estimates the particle size as 10-55 nm and the average size as 28 nm with a spherical shape. Furthermore, biological studies such as antibacterial activity was performed by the broth dilution method whereas antioxidant was studied through the DPPH radical scavenging technique. To compare the antibacterial activity between Gram-positive and Gram-negative pathogens, the highest bacterial growth of inhibition was observed for Pseudomonas aeruginosa than Staphylococcus aureus when increasing the concentration of the plant extract and Ma-Ag NPs. The scavenging activity of DPPH for both leaf extract and synthesized Ma-Ag NPs was represented in a dose-dependent manner (0.1-1.0 mg/mL), Ma-Ag NPs have shown a significant scavenging activity ranging from 39 to 54% with an average IC50 value of 0.87 ± 0.08. Furthermore, a molecular docking study was performed to confirm the binding interaction outline between the bioactive molecule methyl commate A, Ma-Ag NPs, and proteins such as Aminotransferase and Tyrosyl-tRNA synthetase active sites. The highest interaction tendency was observed between the Aminotransferase and methyl commate A with a binding energy of - 7.79 kcal/mol-1. The high electronegative oxygen of the ligand interacts with H-N- of Lys98 (-O--H-N-) through the formation of hydrogen bond by 3.53A° distance. In addition, the photocatalytic efficiency of Ma-Ag NPs was studied with methylene blue dye degradation under sunlight irradiation at different time intervals. The attained photocatalytic degradation efficiency was 98.3% after 120 min.


Assuntos
Nanopartículas Metálicas , Simulação de Acoplamento Molecular , Prata , Águas Residuárias , Nanopartículas Metálicas/química , Prata/química , Águas Residuárias/química , Química Verde , Antibacterianos/farmacologia , Antibacterianos/química , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Pseudomonas aeruginosa/efeitos dos fármacos , Antioxidantes/química
6.
Environ Geochem Health ; 46(9): 365, 2024 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-39141250

RESUMO

Rice (Oryza sativa) is an important nutritional grain for the majority of Asian countries, but it is also a major source of cadmium (Cd) accumulation. A pot experiment was carried out to investigate the Cd uptake and translocation of high Cd (IR-50) and low Cd (White Ponni) rice cultivars in Cd-contaminated soils. The findings revealed that Cd impacts on rice development and growth differed depending on rice cultivars. Soil Cd levels in the seedling stage exceeded the critical levels (3-6 mg kg-1) only 5.0 mg kg-1 Cd treatment for the IR-50 (7.47 mg kg-1). At higher Cd treatments (1.0 and 5.0 mg kg-1), morphometric characteristics and yield of grains showed a declining and increasing trend in both rice varieties, respectively. The accumulation of Cd was higher in soil and roots during seedling and tillering stages, whereas in booting and maturity stages increased in stems and leaves in IR-50 and WP rice varieties. Cd levels in rice grains above the maximum allowable limit (0.4 mg kg-1) only in IR-50 (0.51 mg kg-1) rice cultivar at maturity stage. The EF of Cd were classified as minor enrichment to 'moderate enrichment' in both rice cultivars. TF values exhibited > 1 in booting and maturity stages in both rice cultivars at higher Cd treatments. The study concluded that the IR-50 rice variety exhibited increased Cd intake and transported to various parts of rice plants, particularly grains. The findings indicate that WP rice cultivar is more resistant to Cd toxicity, reducing health hazards for persons who preferred the staple food rice.


Assuntos
Cádmio , Oryza , Poluentes do Solo , Oryza/metabolismo , Oryza/crescimento & desenvolvimento , Cádmio/metabolismo , Poluentes do Solo/metabolismo , Raízes de Plantas/metabolismo , Plântula/metabolismo , Plântula/crescimento & desenvolvimento , Oligoelementos/metabolismo
7.
Luminescence ; 39(8): e4847, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-39192172

RESUMO

In modern times, nanoparticles have materialized as indispensable things in contemporary medicine, with a variety of uses in clinical, drug and gene conveyance. In the present study, TiO2 nanoparticles (NPs) prepared from the leaf extracts of Mollugooppositifolia and Trianthema portulacastrum were compared with the chemical TiO2-NPs for antibacterial and antioxidant activities and environment-friendly nature through various tools like the UV-visible, X-ray diffraction with the aid of other analytical techniques like HR-TEM, Fourier transform infrared (FT-IR) and photoluminescence spectroscopic techniques. The morphology of green TiO2-NPs is found to be spherical, which is supported by HR-TEM images. FT-IR analyses and X-ray diffraction data ensure that the polycrystalline characters of TiO2-NPs alike to the presence of metal oxide. TiO2-NPs showed a possible photocatalytic activity for the ruin of acid black 1 dye after disclosure to sunlight. The chemical and green methods of TiO2-NPs have acid black 1 dye decomposition rates of 86.66% and 94.33%, respectively. The synthesized TiO2-NPs are also assessed for antimicrobial and antioxidant activities. Green TiO2-NPs exhibit antibacterial activity against Pseudomonas aeruginosa (17 + 0.56 mm) and Staphylococcus aureus (16 + 0.24 mm) at concentrations as low as 100 µL. The green TiO2-NPs showed high inhibition of DPPH I radical (50 µg/m) at 95.17 ± 21. Therefore, TiO2-NPs represent eco-friendly properties that aid in the degradation of dyes due to their antioxidant activity.


Assuntos
Antibacterianos , Antioxidantes , Titânio , Antioxidantes/química , Antioxidantes/farmacologia , Antioxidantes/síntese química , Titânio/química , Titânio/farmacologia , Antibacterianos/farmacologia , Antibacterianos/química , Antibacterianos/síntese química , Nanopartículas/química , Testes de Sensibilidade Microbiana , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Corantes/química , Corantes/farmacologia , Luminescência , Staphylococcus aureus/efeitos dos fármacos , Tamanho da Partícula , Folhas de Planta/química , Compostos de Bifenilo/antagonistas & inibidores , Compostos de Bifenilo/química
8.
Luminescence ; 39(8): e4846, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-39090987

RESUMO

Antibiotic residues persist in the environment and represent serious health hazards; thus, it is important to develop sensitive and effective detection techniques. This paper presents a bio-inspired way to make water-soluble fluorescent polymer carbon dots (PCDs@PVA) by heating biomass precursors and polyvinyl alcohol (PVA) together. For example, the synthesized PCDs@PVA are very stable with enhanced emission intensity. This property was observed in a wide range of environmental conditions, including those with changing temperatures, pH levels, UV light, and ionic strength. PCDs@PVA detected the antibiotic chlortetracycline (CTCs) with great selectivity against structurally related compounds and a low detection limit of 20 nM, demonstrating outstanding sensitivity and specificity. We confirmed the sensor's practical application through real sample analysis, yielding recovery rates of 98%-99% in samples of milk, honey, and river water. The synthesized PCDs@PVA fluorescence sensor was successfully used for CTCs detection in real samples.


Assuntos
Carbono , Clortetraciclina , Corantes Fluorescentes , Álcool de Polivinil , Pontos Quânticos , Clortetraciclina/análise , Álcool de Polivinil/química , Carbono/química , Corantes Fluorescentes/química , Corantes Fluorescentes/síntese química , Pontos Quânticos/química , Animais , Leite/química , Antibacterianos/análise , Antibacterianos/química , Antibacterianos/síntese química , Limite de Detecção , Mel/análise , Polímeros/química , Polímeros/síntese química , Poluentes Químicos da Água/análise , Rios/química , Espectrometria de Fluorescência , Concentração de Íons de Hidrogênio
9.
Eur J Pharm Sci ; 200: 106842, 2024 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-38936514

RESUMO

Current treatment for Glioblastoma Multiforme (GBM) is not efficient due to its aggressive nature, tendency to infiltrate surrounding brain tissue, and chemotherapy resistance. Tetrahydroquinoline scaffolds are emerging as a new class of drug for treating many human cancers including GBM. This study investigates the cytotoxicity effect of eight novel derivatives of 2-((3,4-dihydroquinolin-1(2H)-yl)(aryl)methyl)phenol, containing substitute 1 with reduced dihydroquinoline fused with cyclohexene ring and substitute 2 with phenyl and methyl group. The 4-position of the aryl ring was determinant for the desired cytotoxicity, and out of the 8 synthesized compounds, the 4-trifluoromethyl substituted derivative (4ag) exhibited the most anti-GBM potential effect compared to the standard chemotherapeutic agent, temozolomide (TMZ), with IC50 values of 38.3 µM and 40.6 µM in SNB19 and LN229 cell lines, respectively. Our results demonstrated that 4ag triggers apoptosis through the activation of Caspase-3/7. In addition, 4ag induced intracellular reactive oxygen species (iROS) which in turn elevated mitochondrial ROS (mtROS) and causes the disruption of the mitochondrial membrane potential (Δψmt) in both GBM cells. This compound also exhibited anti-migratory properties over the time in both the cell lines. Overall, these findings suggest that tetrahydroquinoline derivative, 4ag could lead to the development of a new drug for treating GBM.


Assuntos
Antineoplásicos , Apoptose , Glioblastoma , Potencial da Membrana Mitocondrial , Quinolinas , Espécies Reativas de Oxigênio , Humanos , Glioblastoma/tratamento farmacológico , Glioblastoma/patologia , Glioblastoma/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Apoptose/efeitos dos fármacos , Quinolinas/farmacologia , Quinolinas/química , Linhagem Celular Tumoral , Antineoplásicos/farmacologia , Antineoplásicos/química , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Neoplasias Encefálicas/tratamento farmacológico , Neoplasias Encefálicas/metabolismo , Neoplasias Encefálicas/patologia , Sobrevivência Celular/efeitos dos fármacos , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/metabolismo , Caspase 3/metabolismo
10.
Environ Geochem Health ; 46(7): 246, 2024 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-38864996

RESUMO

In the pursuit of efficient photocatalytic materials for environmental applications, a new series of g-C3N4/N-doped CeO2 nanocomposites (g-C3N4/N-CeO2 NCs) was synthesized using a straightforward dispersion method. These nanocomposites were systematically characterized to understand their structural, optical, and chemical properties. The photocatalytic performance of g-C3N4/N-CeO2 NCs was evaluated by investigating their ability to degrade methylene blue (MB) dye, a model organic pollutant. The results demonstrate that the integration of g-C3N4 with N-doped CeO2 NCs reduces the optical energy gap compared to pristine N-doped CeO2, leading to enhanced photocatalytic efficiency. It is benefited from the existence of g-C3N4/N-CeO2 NCs not only in promoting the charge separation and inhibits the fast charge recombination but also in improving photocatalytic oxidation performance. Hence, this study highlights the potential of g-C3N4/N-CeO2 NCs as promising candidates for various photocatalytic applications, contributing to the advancement of sustainable environmental remediation technologies.


Assuntos
Cério , Luz , Azul de Metileno , Nanocompostos , Azul de Metileno/química , Cério/química , Nanocompostos/química , Catálise , Poluentes Químicos da Água/química , Grafite/química , Processos Fotoquímicos , Fotólise , Compostos de Nitrogênio
11.
Environ Res ; 258: 119474, 2024 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-38914253

RESUMO

In this study, we studied the conversion of Jatropha curcas oil to biodiesel by using three distinct reactor systems: microchannel, fixed bed, and microwave reactors. ZSM-5 was used as the catalyst for this conversion and was thoroughly characterized. X-ray diffraction was used to identify the crystalline structure, Brunauer-Emmett-Teller analysis to determine surface area, and temperature-programmed desorption to evaluate thermal stability and acidic properties. These characterizations provided crucial insights into the catalyst's structural integrity and performance under reaction conditions. The microchannel reactor exhibited superior biodiesel yield compared to the fixed bed and microwave reactors, and achieved peak efficiency at 60 °C, delivering high FAEE yield (99.7%) and conversion rates (99.92%). Ethanol catalyst volume at 1% was optimal, while varying flow rates exhibited trade-offs, emphasizing the need for nuanced control. Comparative studies against microwave and fixed-bed reactors consistently favored the microchannel reactor, emphasizing its remarkable FAME percentages, high conversion rates, and adaptability to diverse operating conditions. The zig-zag configuration enhances its efficiency, making it the optimal choice for biodiesel production and showcasing promising prospects for advancing sustainable biofuel synthesis technologies.


Assuntos
Biocombustíveis , Jatropha , Micro-Ondas , Óleos de Plantas , Biocombustíveis/análise , Jatropha/química , Óleos de Plantas/química , Catálise , Zeolitas/química , Difração de Raios X , Reciclagem
12.
Int J Biol Macromol ; 270(Pt 2): 132457, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38772467

RESUMO

Transcriptional events play a crucial role in major cellular processes that specify the activity of an individual cells and influences cell population behavior in response to environment. Active (ON) and an inactive (OFF) states controls the transcriptional burst. Yet, the mechanism and kinetics of ON/OFF-state across the different growth phases of Escherichia coli remains elusive. Here, we have used a single mRNA detection method in live-cells to comprehend the ON/OFF mechanism of the first transcriptional (TF) and consecutive events (TC) controlled by lactose promoters, Plac and Plac/ara1. We determined that the duration of TF ON/OFF has different modes, exhibiting a close to inverse behavior to that of TC ON/OFF. Dynamics of ON/OFF states in fast and slow-dividing cells were affected by the promoter region during the initiation of transcription. Period of TF ON-state defines the behavior of TC by altering the number and the frequency of mRNAs formed. Furthermore, we have shown that delayed OFF-time in TF affects the dynamics of TC in both states, which is mainly determined by the upstream promoter region. Furthermore, using elongation arrest experiments, we independently validate that mRNA noise in TC is governed by the delayed OFF-period in TF. We have identified the position of the regulatory regions that plays a crucial role in noise (Fano) modulation. Taken together, our results suggest that the dynamics of the first transcriptional event, TF, pre-defines the diversity of the population.


Assuntos
Escherichia coli , Regulação Bacteriana da Expressão Gênica , Regiões Promotoras Genéticas , RNA Mensageiro , Escherichia coli/genética , Escherichia coli/crescimento & desenvolvimento , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Transcrição Gênica , Cinética
13.
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
14.
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
15.
ACS Omega ; 9(13): 15239-15250, 2024 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-38585078

RESUMO

A novel integrated electrochemical oxidation (EO) and bacterial degradation (BD) technique was employed for the remediation of the chloropyridinyl and chlorothiazolyl classes of neonicotinoid (NEO) insecticides in the environment. Imidacloprid (IM), clothianidin (CL), acetamiprid (AC), and thiamethoxam (TH) were chosen as the target NEOs. Pseudomonas oleovorans SA2, identified through 16S rRNA gene analysis, exhibited the potential for BD. In EO, for the selected NEOs, the total percentage of chemical oxygen demand (COD) was noted in a range of 58-69%, respectively. Subsequently, in the biodegradation of EO-treated NEOs (BEO) phase, a higher percentage (80%) of total organic carbon removal was achieved. The optimum concentration of NEOs was found to be 200 ppm (62%) for EO, while for BEO, the COD efficiency was increased up to 79%. Fourier-transform infrared spectroscopy confirms that the heterocyclic group and aromatic ring were degraded in the EO and further utilized by SA2. Gas chromatography-mass spectroscopy indicated up to 96% degradation of IM and other NEOs in BD (BEO) compared to that of EO (73%). New intermediate molecules such as silanediamine, 1,1-dimethyl-n,n'-diphenyl produced during the EO process served as carbon sources for bacterial growth and further mineralized. As a result, BEO enhanced the removal of NEOs with a higher efficiency of COD and a lower consumption of energy. The removal efficiency of the NEOs by the integrated approach was achieved in the order of AC > CL > IM > TH. This synergistic EO and BD approach holds promise for the efficient detoxification of NEOs from polluted environments.

18.
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
19.
Front Microbiol ; 15: 1297721, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38544856

RESUMO

Background: Cooling towers are specialized heat exchanger devices in which air and water interact closely to cool the water's temperature. However, the cooling water contains organic nutrients that can cause microbial corrosion (MC) on the metal surfaces of the tower. This research explores the combined wastewater treatment approach using electrochemical-oxidation (EO), photo-oxidation (PO), and photoelectrochemical oxidation (PEO) to contain pollutants and prevent MC. Methods: The study employed electro-oxidation, a process involving direct current (DC) power supply, to degrade wastewater. MC studies were conducted using weight loss assessments, scanning electron microscopy (SEM), and x-ray diffraction (XRD). Results: After wastewater is subjected to electro-oxidation for 4 h, a notable decrease in pollutants was observed, with degradation efficiencies of 71, 75, and 96%, respectively. In the wastewater treated by PEO, microbial growth is restricted as the chemical oxygen demand decreases. Discussion: A metagenomics study revealed that bacteria present in the cooling tower water consists of 12% of Nitrospira genus and 22% of Fusobacterium genus. Conclusively, PEO serves as an effective method for treating wastewater, inhibiting microbial growth, degrading pollutants, and protecting metal from biocorrosion.

20.
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.

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