Chemical Papers最新文献

Nocardia farcinica is a Gram-positive bacteria that causes opportunistic infections. Chronic lung illness, diabetes mellitus, renal disease, immunosuppressive treatment, hematological neoplasm, and transplant recipients are predisposing factors. Brain abscesses, skin or soft tissue infections, and pulmonary infections are examples of clinical manifestations of Nocardia farcinica infection. Nocardia farcinica is the rare cause of brain abscesses, making up 2% of all intracranial abscesses. In the present study, the subtractive proteomics approach was used for potential drug targets identification in the Nocardia farcinica strain IFM 10152 to evaluate the pathogen-specific and essential proteins by using various bioinformatics tools. A total eighteen specific pathways were found in Nocardia farcinica strain IFM 10152 and eight proteins were involved in these specific pathways. A total of three proteins were found as Druggable. Furthermore, 3D structure prediction for one of the drug targets putative penicillin binding protein was carried out by Alpha-Fold2 one of the deep learning approaches. Virtual screening was performed for the identified drug target. To evaluate the stability of the new hits against the drug target molecular dynamics simulation was carried out. This study provides valuable information about the discovery of new drug targets that may help to eradicate Nocardia farcinica associated infections. To the best of our knowledge, this is the first attempt to apply the subtractive proteomics approach on the complete proteomic data of Nocardia farcinica strain IFM 10152, thus providing an opportunity to predict specific therapeutic targets and their inhibitors against Nocardia farcinica.

By means of density functional theory and first-principle molecular dynamics (FPMD) simulations, the corrosion inhibition potential of allopurinol (Allo), oxypurinol (Oxy), and thiopurinol (Thio) expired drugs toward the aluminium (Al) (111) surface was thoroughly examined. ESP maps and FMOs analysis indicated the electron-donating nature of the studied drugs. From global reactivity descriptors, the potential of the Allo, Oxy, and Thio drugs in gas and aqueous phases as corrosion inhibitors was confirmed. Thio drug showed lower IP and higher EA values than the other investigated drugs, illustrating its higher reactivity. Further, the lowest value of ƞ and the highest value of σ were found for the Thio drug, indicating its high potential as a corrosion inhibitor. Employing FPMD simulations, the most stable configurations of the drug∙∙∙Al (111) complexes were determined, and the corresponding interaction and binding energies were estimated. According to the energetic affirmations, the Thio drug demonstrated the largest affinity to inhibit the Al (111) surface with an interaction energy (E_int) value of − 25.12 kcal/mol. The findings of the charge transfer (Q_t) were in line with the E_int, in which the Q_t of the drug∙∙∙Al (111) complexes decreased in the order Thio∙∙∙ > Allo∙∙∙ > Oxy∙∙∙Al (111) with values of − 0.5119, − 0.2737, and − 0.2471 e, respectively. The obtained results would provide fundamental insights into the promising application of Allo, Oxy, and Thio expired drugs as corrosion inhibitors, especially for aluminium surface.

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Eugenol is a lignin-derived aromatic model compound extracted from the lignin and has been used for various reactions. The eugenol esterification to eugenol benzoate with benzoic acid was studied using different deep eutectic solvents (DESs) as catalysts. DESs are a type of ionic liquid that is formed by combining a hydrogen bond donor with a hydrogen bond acceptor. In the current paper, carboxylic acids such as oxalic acid, acetic acid, p-toulenesulfonic acid (p-TSA) and tartaric acid were used as hydrogen bond donors to form choline-based DESs which were used as catalysts in esterification reactions. The catalysts were screened based on the conversion and p-TSA based DES was found to be best and used for further experiments. Effects of parameters (eugenol to benzoic acid ratio, reaction time, temperature, and catalyst loading) on the yield of eugenol benzoate were studied. The highest eugenol conversion was obtained as 90.42% (383 K, 0.02 g/cm³ catalyst, molar ratio of eugenol to benzoic acid = 1:5, 600 rpm, 3 h).

The desire for products that are healthier, safer, and better for the environment is on the rise in society. Chalcones are aromatic ketones with anxiolytic and antimicrobial properties. The limited solubility, bioavailability, and long-term stability of chalcones hinder their application. Nanoemulsions can be used as a drug transport system to address this problem. The primary objective of our research was to design nanoemulsions through ANOVA (NE) with nanoscale droplets that would maintain exceptional stability, optimizing the anxiolytic capacity of chalcones. Sodium alginate and chitosan were assessed as the continuous phase material, while commercial soybean oil and mineral oil were used as adjuvants, besides surfactant, for the oil phase composition of the droplets. Results showed that the addition of soybean oil improved significantly the stability of the formulations, as did the use of the alginate matrix. The optimal NE showed a nanometer-sized droplet (126 nm) and negative ζ-potential (− 42 mV), showing good stability under different conditions—it synergistically enhances the anxiolytic potential. The mode of operation is associated with the receptors of the serotonergic system (5-HT). Toxicity, locomotion and anxiety tests performed using the zebrafish animal model showed a promising dose (0.0325 mg/mL) for the development of compounds with anxiolytic properties.

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This work shows the utilization of glycyrrhizic acid (GLA) as a corrosion inhibitor for steel within acidic environments. Employing a multifaceted approach, the investigation integrates spectral analysis, thermal testing, electrochemical assessments, surface characterization techniques, and computational modeling to elucidate GLA’s mechanisms of corrosion protection. A pivotal finding of this research underscores GLA’s capacity to engage with metal surfaces through both physisorption and chemisorption mechanisms, facilitated by its inherent functional groups. Moreover, thermal analysis reveals GLA’s robust stability up to temperatures of 170°C, rendering it well suited for applications within moderate-temperature environments. Electrochemical analyses unveil a notable augmentation in charge transfer resistance, escalating from 5.18 to 90.64Ω/cm², alongside a concomitant reduction in corrosion current density from 15.64 to 0.83μA/cm², particularly evident at 200mg/L. Surface examinations corroborate the ameliorated state of surfaces treated with GLA, with discernible compositional alterations indicative of efficacious corrosion inhibition. Adsorption studies align with the Langmuir model, suggesting monomolecular adsorption behavior. Thermodynamic scrutiny reveals a spontaneous and endothermic process, with heightened efficacy observed at elevated temperatures. Lastly, the computational model unveils robust interactions between GLA and the metal surface, characterized by interaction energies reaching as low as −2033.91kJ/mol, thus underscoring the stability inherent in the protective layer formed by GLA.

Herein, we present a new eco-friendly microextraction method based on the magnetite/multi-walled carbon nanotubes reinforced and natural deep eutectic-filled hollow fiber solid/liquid phase microextraction, abbreviated as HF-SLPME, combined with HPLC–DAD analysis. This method has been developed to determine trace levels of phthalate esters, including diethyl phthalate, benzyl butyl phthalate, and di-iso-butyl phthalate in urine, blood plasma, tap water, and groundwater samples. The natural deep eutectic solvents were prepared using terpenoid-derived natural compounds containing menthol and camphor in various ratios. The HF-SLPME device was constructed by reinforcing and immobilizing the synthesized Fe₃O₄-MWCNTs within the pores of a 2.5 cm segment of hollow fiber microtube through ultrasonication, followed by filling the lumen with the natural deep eutectic solvent with both ends heat sealing. The extraction process was conducted in direct immersion mode. Values of crucial variables for HF-SLPME were optimized through a multivariate methodology based on a central composite design, with 30 extraction tests performed to determine the best conditions. The method exhibited good linearity (correlation coefficients R² > 0.996) over a dynamic range lower than 0.927–10³ µg L⁻¹. The results show that the limits of detection/quantification for the chosen PEs ranged from 0.19 to 0.27/ 0.65 to 0.92 µg L⁻¹ with enrichment factor˃ 37.24. As evidenced by intra- and inter-day precisions, satisfactory reproducibility was achieved with relative standard deviations (RSDs) below 3.7% and 5.1%, respectively. The recoveries of the selected phthalate esters from spiked real samples ranged from 88.4 to 111.1%, with relative standard deviations between 2.3 and 6.5%. This HF-SLPME-HPLC–DAD method offered a new, cost-effective, sensitive microextraction approach for determining and quantifying phthalate esters in aqueous samples with complex matrices.

The use of reverse osmosis (RO) for desalination holds great promise for addressing water scarcity issues in many parts of the world. However, membrane fouling is a significant impediment in this regard, as it reduces the quality and quantity of water produced, increases energy consumption, requires cleaning, and shortens membrane life. The use of granular activated carbon (GAC) adsorption in conjunction with ultrafiltration (UF) as a pre-treatment ensures that high-quality seawater enters the desalination process free of contaminants that could harm the plant. This method increases the efficiency and longevity of the equipment, lowers maintenance costs, and produces high-quality desalinated water for a variety of applications. In this study, GAC was made from commercially available charcoal and used to remove organic compounds, heavy metals, and microbiological contaminants from seawater. A preliminary study was conducted to determine GAC’s effectiveness in removing methylene blue (MB). The removal efficiency was found to be 78 and 99% at initial MB concentrations of 50 and 10 mg/L, respectively. The isotherm modeling confirms that the adsorption process follows the Langmuir model. In addition, the kinetic study demonstrated that MB adsorption on GAC follows the pseudo-second-order model. GAC filtration removed more than 99% of COD and significantly reduced metal concentrations such as Zn, Cu, and Cd. Bacteriological analysis of seawater treated with GAC revealed a significant reduction in total and fecal coliforms, as well as fecal streptococci, indicating the efficacy of the GAC/adsorption filtration system.

In general, the pollutants can be sequestrated from wastewater by adsorption technology under batch or continuous flow conditions. Although there are a good number of reviews on pollutants uptake under batch conditions and related operational factors affecting the process, reviews on pollutants uptake under column conditions are relatively few. Hence, the importance of this review comes as it evaluated the performance of many adsorbents under continuous flow conditions, which is considered more practical than batch process. Based on this aim, many synthetic and non-conventional adsorbents were examined which utilized for dyes uptake under batch and continuous flow conditions. It is necessary to assess the performance of the examined adsorbents using both processes to determine the most appropriate one, taking into account the high production cost of synthetic adsorbents. The performance of sixty nine adsorbents for removing different classes of dyes using batch and column type processes are examined in this review. The results are collected under the following criteria: (a) The adsorbent should have maximum uptake capacity higher than 100 mg g⁻¹; (b) Column saturation capacity, operational factors and service time for dye uptake are reported; (c) Adsorbent recycling under dynamic conditions is reported. Based on the earlier criteria a screening guide was proposed for the most efficient dye adsorbent under column conditions: (a) column saturation capacity > 184 mg g⁻¹; (b) column service time < 10 h; (c) the adsorbent should be used up to 5 cycles after regeneration with a green solvent. The most efficient synthetic adsorbent is vinylpyridine-methacrylic acid cryogel toward Basic Blue 9 with column capacity 388 mg g⁻¹, service time 0.8 h and used for 4 cycles with 100% efficiency. For non-conventional adsorbents, modified-chitosan is outstanding toward Basic Blue 9 with column capacity 379 mg g⁻¹, service time 3.4 h and used for 5 cycles with a final efficiency 93%.

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Zirconium dioxide nanoparticles (ZrO₂ NPs) were synthesized using simple, lucrative and easily scalable flame pyrolysis method by directly burning the precursor solution in air. ZrO₂ NPs were collected in the form of white soot one from cold surface of conical Flask (F-ZrO₂ NPs) and another from direct crucible (C-ZrO₂ NPs). The synthesized ZrO₂ NPs were characterized by various techniques viz., Fourier Transform Infrared (FT-IR) spectroscopy, X-ray Diffraction (XRD), UV–vis absorption spectroscopy, Energy Dispersive X-ray Spectroscopy (EDS), Scanning Electron Microscopy (SEM), Transmission Electron Microscopy (TEM), Field Emission Scanning Electron Microscopy (FE-SEM), High Resolution Transmission Electron Microscopy (HR-TEM). The synthesised ZrO₂ NPs demonstrated the monoclinic (m-ZrO₂) and tetragonal (t-ZrO₂) mixed phases with an average crystalline size of 16.96 nm. The morphological analysis elucidated the uniform distribution of spherically shaped ZrO₂ NPs. The dye degradation performance of synthesized nanoparticles was experienced for the complexed structured Methylene Blue (MB) azo dye meant for environmental applications. The synthesized nanoparticles demonstrated excellent dye removal efficiency of 97.90% along with successful reusability up to six cycles for removal of aqueous Methylene Blue (MB) hazardous colorant dye. So, the synthesised ZrO₂ NPs designated as finest contender for the wastewater treatment and various environmental applications.

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Considering the dramatic health and economic period that the world experienced during the COVID-19 pandemic, finding new drugs for the treatment of this disease is still a great scientific concern. Favipiravir (6-fluoro-3-hydroxypyrazine-2-carboxamide) is an important selective antiviral against RNA-based viruses, like SARS‐CoV‐2 virus causing COVID-19 disease, and has recently attracted considerable interest. The behavior of Favipiravir in various solvents including water, methanol, ethanol, isopropanol, methyl tert-butyl ether (MTBE), and dimethyl sulfoxide (DMSO) was investigated. A novel iron (III) complex compound derived from FAV as the ligand was synthesized. Subsequently, the newly synthesized complex was subjected to various analytical and spectroscopic techniques, including UV and infrared spectroscopy, mass spectrometry, stoichiometry analysis using the molar ratio method, and thermogravimetric analysis (TG–DTA). It was observed that the keto/enolic equilibrium of favipiravir is influenced by the choice of diluent, with the enol tautomer being the predominant form. Further analysis revealed that the isolated metal complex exhibits a tetrahedral geometry. The complexation reaction is more favorable in a protic medium than in an aprotic one, primarily due to the easier deprotonation in protic environments. Additionally, the molecular structures of the free ligand and its metal complex compound were optimized using density functional theory (DFT) simulations. This study offers valuable insights into the quantum chemical properties related to the structure. The simulation indicates significant chemical stability and a pronounced electrophilic character of the iron complex. Overall, these findings contribute to a deeper understanding of the interaction dynamics and stability of favipiravir's metal complexes.

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