A simple heterogeneous catalytic process has been established for the single-step synthesis of fused benzoxazinones, quinazolinones, and thiadazines through Markownikoff's hydroamination followed by ...intramolecular cyclization using Cuβ zeolite. The probability and limitations of this catalytic approach were explored using various substrates. The efficiency and feasibility of scaling up the current catalytic system were demonstrated through gram-scale experiments. Moreover, the catalyst was reused for up to five cycles with no noticeable decrease in its catalytic effectiveness. Furthermore, the synthesized compounds were subjected to in vitro assessment to determine their potential as anticancer agents against human cervical epithelioid carcinoma (HeLa), mouse breast cancer (4T-1), and human lung adenocarcinoma (A-549) cell lines. Cytotoxicity studies revealed that 3f, 3b′, 3d′, and 3g′ compounds exhibit anti-cancer activity against breast, cervical and lung cancer cells. Additionally, their antimicrobial activity against bacteria and yeast was also evaluated. The compound 3i exhibited superior antifungal activity against Candida albicans.
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•Cuβ zeolite shows good catalytic activity for synthesis of N-heterocyclic moieties.•Potentiality of this method is ensured with various substrates in good yields.•This approach benefits industrial applications by gram scale experiments.•The catalyst was successfully reused for up to five cycles.•The obtained products were found to be biologically active.
Polycyclic aromatic hydrocarbons (PAHs) are omnipresent, persistent, and carcinogenic pollutants continuously released in the atmosphere due to the rapid increase in population and industrialization ...worldwide. Hence, there is an ultimate rise in concern about eliminating the toxic PAHs and their related aromatic hydrocarbons from the air, water, and soil environment by employing efficient removal technologies using nanoparticles as a catalyst. Here, the degradation of selective PAHs viz., anthracene and benzene using laboratory synthesized rGO-Ag-Cu-Ni nanocomposite (catalyst) was studied. Characterization studies revealed the nanocomposites exhibited surface plasma resonance at 350 - 450 nm, confirming the presence of Ag, Cu, and Ni metal ions embedded on the reduced graphene substrate. It was found that the nanocomposites synthesized were spherical, amorphous in nature, and aggregated together with measurements ranging from 423 to 477 nm. An SEM-EDX analysis of the nanocomposite demonstrated that it contained 25.13% O, 14.24% Ni, 27.79% Cu, and 32.84% Ag, which confirms the synthesis of the nanocomposite. Crystalline, sharp nanocomposites of average size 17–41 nm with an average diameter of 118.5 nm (X-ray diffraction and DLS) were observed. FTIR spectra showed that the nanocomposites had the functional groups alkanes, alkenes, alkynes, carboxylic acids, and halogen derivatives. Batch adsorption studies revealed that the maximum degradation achieved at optimum nano-composite concentration of 10 μg/mL, pH value of 5, PAHs concentration of 2 μg/mL and effective irradiation source being UV radiations in the case of both benzene and anthracene pollutants. The degradation of benzene and anthracene followed Freundlich & Langmuir isotherm with the highest R2 value of 0.9894 & 0.9885, respectively. Adsorption kinetic studies under optimum conditions revealed that the adsorption of both benzene and anthracene followed Pseudo-second order kinetics. Antimicrobial studies revealed that the synthesized nano-composite exhibited potential antimicrobial activity against Gram positive bacterium (Bacillus subtilis, Staphylococcus aureus), Gram negative bacterium (Klebsiella pneumonia, Escherichia coli) and fungal strain (Aspergillus niger) respectively. Thus, the synthesized rGO-Ag-Cu-Ni nano-composite acts as an effective antimicrobial agent as well as a PAHs degrading agent, helping to overcome antibiotics resistance and to mitigate the overgrowing PAHs pollution in the environment.
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•Synthesis of rGO-Ag-Cu-Ni nano-composite and its characterization using UV spectroscopy, FTIR, SEM-EDX, XRD and DLS analysis were conducted•Batch adsorption studies were conducted with various parameters viz, concentration of catalyst (rGO-Ag-Cu-Ni nano-composite).•Concentration of anthracene and benzene (pollutant), pH and irradiation source followed by Kinetic and isotherm adsorption studies.•Antimicrobial potential of synthesized nano-composite (rGO-Ag-Cu-Ni nano-composite) were examined.
To degrade anthracene, magnetite nanoparticles were produced using a simple co-precipitation process. The fabricated nanoparticles have been analyzed for structural and optical properties. XRD ...examination revealed that the produced Fe3O4 nanoparticles were cubic phase, having a mean crystallite dimension of 18.84 nm. DLS determined the hydrodynamic diameter of Fe3O4 nanoparticles to be 182 nm. UV-Vis research revealed that Fe3O4 nanoparticles absorb at 390 nm. A peak at 895 cm-1 in the FT-IR study indicated the metal-oxygen connection. The synthesized Fe3O4 nanoparticles demonstrated an effective photocatalytic performance towards anthracene degradation and was found to be 86.55%. Furthermore, Fe3O4 nanoparticles showed the highest antimicrobial activity against Bacillus subtilis was 19.43 mm. The present study is the first and foremost study determining the dual role of Fe3O4 nanoparticles towards bioremediation and biomedical applications.
Honey, valued for its nutritional and antimicrobial benefits, has experienced an increased production in recent decades. However, this rise has been accompanied by concerns of adulteration, often ...involving the fraudulent addition of sugars. Our study sought to compare the physicochemical and isotopic properties of various honeys available to Chilean consumers, assessing the extent of adulteration. Samples included honey produced from bees that fed on multiple flowers and those fed by ulmo flowers – an endemic species of South America that produces a high-quality, high-cost honey – and analyzed for antimicrobial activity against Escherichia coli, Staphylococcus aureus and Pseudomonas aeruginosa. The analysis of ash content (%), moisture (%), pH and total phenolic content (mg GAE/100 g honey) found little obvious differences among honeys regardless of the feeding flowers (multifloral vs ulmo), type of purchase market (formal vs informal) or origin of the honeys (Central vs Southern Chile). However, the use of stable isotope analysis (δ13C and δ15N) of honey provided a powerful means to identify the degree of adulteration prior to the point of sale. Multifloral honeys purchased at informal markets were all adulterated, and ulmo honeys included both the least and most adulterated honeys. Regarding their antimicrobial activity, most multifloral honeys were less effective than ulmo honeys. Notably, while multifloral honey activity was independent of adulteration, the antimicrobial activity of ulmo honey was negatively affected by adulteration.
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•Significant lower δ13C values (pointing to adulteration) were observed in multifloral honey.•Honeys purchased at formal markets were unadulterated.•Ulmo honeys were the least and most adulterated honeys, associated to market type.•Most of the ulmo honeys had a higher antimicrobial activity than multifloral honeys.•Independently of adulteration, all multifloral honeys had the same antimicrobial activity.
Recently, antibiotic resistance of pathogens has grown given the excessive and inappropriate usage of common antimicrobial agents. Hence, producing novel antimicrobial compounds is a necessity. ...Carbon nanomaterials (CNMs) such as carbon nanotubes, graphene/graphene oxide, and fullerenes, as an emerging class of novel materials, can exhibit a considerable antimicrobial activity, especially in the nanocomposite forms suitable for different fields including biomedical and food applications. These nanomaterials have attracted a great deal of interest due to their broad efficiency and novel features. The most important factor affecting the antimicrobial activity of CNMs is their size. Smaller particles with a higher surface to volume ratio can easily attach onto the microbial cells and affect their cell membrane integrity, metabolic procedures, and structural components. As these unique characteristics are found in CNMs, a wide range of possibilities have raised in terms of antimicrobial applications. This study aims to cover the antimicrobial activities of CNMs (both as individual forms and in nanocomposites) and comprehensively explain their mechanisms of action. The results of this review will present a broad perspective, summarizes the most remarkable findings, and provides an outlook regarding the antimicrobial properties of CNMs and their potential applications.
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•Carbon nanomaterials (CNMs) such as carbon nanotubes, graphene, and fullerenes, are an emerging class of novel materials.•CNMs can exhibit a considerable antimicrobial activity, especially in the nanocomposite forms.•The most important factor affecting the antimicrobial activity of CNMs is their size.•This study aims to cover the antimicrobial activities of CNMs (both as individual forms and in nanocomposites).
Thirteen fused pyridine derivatives have been designed, synthesized and characterized by 1H NMR, 13C NMR and IR spectral data and elemental analysis. Their in vitro antimicrobial activity was ...investigated against some pathogenic bacteria and fungi and the majority of them showed excellent to moderate activity, especially compounds 10 and 18 displaying the potent inhibitory effect against K. pneumoniae with MIC values of 2.44 mM and 8.10 mM, respectively. Their pharmacokinetic assessment also revealed promising druglikeness characteristics and ADME properties. The binding interactions of the most active analogues were performed through molecular docking against Staphylococcus aureus tyrosyl-tRNA synthetase. Results revealed that the enhanced activity of compound 10 can be modulated by the establishment, in 10-tyrosyltRNA synthetase complex, of hydrogen bond interactions between the lone pair of sulfur atom of the thiophen-3-amine ring and the hydrogen atom of the hydroxyl group of TYR 170 of 3.80 Å. These findings suggest that analogues 10 and 18 can be served as best candidates for designing and discovering of novel antimicrobial agents.
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•Novel fused pyridine derivatives were designed, synthesized and characterized.•Their antimicrobial and pharmacokinetic properties were assessed.•Compounds 10 and 18 had the most potent inhibitory activity.•Molecular docking analysis and binding mode were carried out.•The lone pair of sulfur atom (10) governed the enhanced activity.
Sepsis remains a leading cause of death worldwide, despite advances in critical care, and understanding of the pathophysiology and treatment strategies. No specific therapy or drugs are available for ...sepsis. Neutrophils play a critical role in controlling infection under normal conditions, and it is suggested that their migration and antimicrobial activity are impaired during sepsis which contribute to the dysregulation of immune responses. Recent studies further demonstrated that interruption or reversal of the impaired migration and antimicrobial function of neutrophils improves the outcome of sepsis in animal models. In this review, we provide an overview of the associated mediators and signal pathways involved which govern the survival, migration and antimicrobial function of neutrophils in sepsis, and discuss the potential of neutrophils as a target to specifically diagnose and/or predict the outcome of sepsis.
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