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In this study, we aimed to investigate the inhibitory mechanisms of β-glucuronidase by flavonoids derived from Alhagi graecorum through both experimental and computational approaches. The activity of β-glucuronidase was assessed using an in vitro enzyme inhibition assay, where myricetin and chrysoeriol were identified as potent inhibitors based on their low IC₅₀ values. Kinetic studies were conducted to determine the inhibition type, revealing that both compounds exhibit noncompetitive inhibition of β-glucuronidase-catalyzed hydrolysis of PNPG. Molecular docking was employed to explore the binding affinities of the flavonoids, showing that myricetin formed the highest number of polar interactions with the enzyme. Additionally, molecular dynamics (MD) simulations were performed to evaluate the stability of the enzyme-inhibitor complexes, demonstrating consistent trajectory behavior for both compounds, with significant energy stabilization. Interaction energy analyses highlighted the dominant role of electrostatic forces in myricetin's inhibition mechanism, while Van der Waals forces were more prominent for chrysoeriol. The MM/PBSA method was used to calculate the binding free energies, with myricetin and chrysoeriol exhibiting the lowest values. Potential energy landscape analysis further revealed that β-glucuronidase adopts a more closed conformation when bound to these inhibitors, limiting substrate access. These findings suggest that flavonoids from Alhagi graecorum hold promise for clinical applications, particularly in managing drug-induced enteropathy.

This study has provided new insights into the interaction between graphene and DNA nucleobases (adenine, cytosine, and guanine). It compares how each nucleobase interacts with graphene, examining their selectivity and binding energy. The research also explores how these interactions impact the electronic properties of graphene, showing potential applications in graphene-based biosensors and DNA sequencing technologies. Additionally, the findings suggest potential uses in DNA sensing and the functionalization of graphene for various biomedical applications. This study employs density functional theory (DFT) methods, utilizing the B3LYP functional with the 6-311G basis set, to explore the electronic interactions between DNA nucleobases (adenine, cytosine, and guanine) with pure graphene (Gr). We investigate various properties, including adsorption energy, HOMO-LUMO energy levels, charge transfer mechanisms, dipole moments, energy gaps, and density of states (DOS). Our findings indicate that cytosine interacts most favorably with graphene through its oxygen site (Gr-Cyt-O), exhibiting the strongest adsorption. Additionally, adenine's interaction significantly enhances its electronegativity and chemical potential, particularly at the nitrogen position, while decreasing its electrophilicity. Guanine, characterized by the smallest energy gap, demonstrates the highest conductivity among the nucleobases. These results suggest that graphene possesses advantageous properties as an adsorbent for guanine, highlighting its potential applications in biosensor technology.

A simple two step synthetic method for di-doped crystalline mesoporous tin dioxide powder containing antimony and fluoride at ambient pressure and temperature has been developed. This approach produced materials with high surface areas and improved electrical and optoelectrical conductance. The two dopant elements; antimony and fluoride were introduced to tin dioxide by two approaches. Both approaches produced mesoporous tin dioxide with antimony and fluoride that are integrated in the framework. The structures of these materials are analyzed by powder X-ray diffraction, N₂ sorption analysis, transmission electron microscopy, energy dispersive X-ray spectroscopy and X-ray photoelectron spectroscopy. The conductance of the materials improved by factor of 13-34 compared to undoped mesoporous tin dioxide. The effect of the di-doped elements on structure, conductance and optoelectronic properties of these materials are discussed in this paper.

Electrochemically induced, decarboxylative functionalization of chromone-3-carboxylic acids by N-hydroxyphthalimide esters as alkyl radical precursors was studied. Electrochemical protocol offers a sustainable and green approach, obviating the need for catalysts, relying on the direct reduction of NHPI esters using electric current. Developed protocol provides a straightforward route to the synthesis of diverse molecules with potential biological activity.

The Front Cover shows selective production of formic acid from cellobiose, a disaccharide from cellulose, using solid base catalysts in the presence of hydrogen peroxide as an environmentally benign oxidizing agent. Calcium oxide and magnesium oxide are found to afford formic acid at 343 K for 2 h. A combination of Amberlyst-15 as a solid acid and MgO as a solid base allows for a high formic acid yield of 33% under mild reaction conditions. More information can be found in the Research Article by Atsushi Takagaki, Tatsumi Ishihara, and co-workers (DOI: 10.1002/open.202400079).

In this study, Zirconium-modified Engelhard Titanium Silicate 4 (Na-K-ETS-4/xZr) catalysts were synthesized and evaluated for their photocatalytic efficiency in degrading crystal violet (CV) and methylene blue (MB) in aqueous solutions. The catalysts were characterized using XRD, FTIR, SEM, WDXRF, and nitrogen adsorption/desorption isotherms. The results confirmed the successful incorporation of Zr into the ETS-4 framework, with the highest Zr content reaching 9.2 wt %. The photocatalytic performance under visible light irradiation was studied at varying pH levels. The Na-K-ETS-4/6.3Zr catalyst exhibited the highest photodegradation efficiency for CV (76.6 %), while Na-K-ETS-4/8.9Zr achieved 86.6 % efficiency for MB. A combination of Engelhard Titanium Silicate 10, Na-K-ETS-10/6.3Zr and Na-K-ETS-4/8.9Zr significantly enhanced dye degradation, achieving up to 96.5 % efficiency for MB. Kinetic studies indicated that the degradation process follows a non-linear pseudo-first-order model. The catalysts also demonstrated excellent reusability, with minimal efficiency loss after five cycles, and full recovery after an ethanol wash. These findings suggest that Na-K-ETS-4/xZr is a promising candidate for environmental water treatment applications due to its efficient photodegradation performance and stability.

A synthetic approach to imidazoles annulated to saturated six-membered cycles featuring S, SO₂, NH, NCbz was developed. It was achieved by combining the Neber rearrangement and the Marckwald reaction. The Neber rearrangement applied to cyclic ketones allowed us to prepare in hundred gram quantities previously unknown α-amino ketones. Unstable tosyl ketoximes were used without purification immediately after their preparation. α-Amino ketones react with potassium thiocyanate and cyanate in almost a quantitative yield affording highly pure imidazol-2-thiones or imidazol-2-ones. Desulfurization of imidazole-2-thiones using Raney nickel led to the formation of previously unknown 2-unsubstituted fused imidazoles in high yields.

Phosphite antioxidants exhibit superior anti-aging and color-stabilizing properties when incorporated into polymer materials. Their synergistic antioxidative effects are particularly noteworthy when used in combination with hindered phenol antioxidants and other primary antioxidants, serving as effective secondary antioxidants, displaying noteworthy synergistic antioxidation effects. This review systematically classifies the synthetic methods for phosphite antioxidants into three distinct categories based on the types of starting materials: synthesis from phosphorus trichloride, phosphorus-containing esters, and white phosphorus. Additionally, it delineates the reaction mechanisms associated with these approaches and provides an overview of future potential research directions and applications for organophosphorus antioxidants.

Dry methane reforming (DRM) presents a viable pathway for converting greenhouse gases into useful syngas. Nevertheless, the procedure requires robust and reasonably priced catalysts. This study explored using cost-effective cobalt and nickel combined into a single catalyst with different metal ratios. The reaction was conducted in a fixed reactor at 700 °C. The findings indicate that the incorporation of cobalt significantly enhances catalyst performance by preventing metal sintering, improving metal dispersion, and promoting beneficial metal-support interactions. The best-performing catalyst (3.75Ni+1.25Co-ScCeZr) achieved a good conversion rate of CH₄ and CO₂ at 46.8 %, and 60 % respectively after 330 minutes while maintaining good stability. The TGA and CO₂-TPD analysis results show that the addition of Co to Ni reduces carbon formation, and increases the amount of strong basic sites and isolated O₂- species, and the total amount of CO₂ desorbed. These results collectively highlight the potential of cobalt-nickel catalysts for practical DRM applications and contribute to developing sustainable energy technologies.

The present study was designed to measure the potential antiemetic properties of nerolidol (NDL) via in vivo and in silico studies. To induce emesis copper sulfate pentahydrate (CuSO₄.5H₂O) was administered at a dose of 50 mg/kg (orally) to 2-day-old chicks. The test sample (NDL) was given at two doses of 50 and 100 mg/kg. b.w. orally. Additionally, aprepitant (16 mg/kg), domperidone (6 mg/kg), hyoscine (21 mg/kg), ondansetron (5 mg/kg), and diphenhydramine (10 mg/kg) were given also orally as positive controls. To observe the modulatory effects of the test sample, combination therapies with reference drugs were also administered to three different groups of animals. Molecular docking and visualization of ligand-receptor interaction were performed against several emesis-inducing receptors (5HT₃, D₂, D₃, H₁, and M₁-M₅) using diverse computational tools. Pharmacokinetics and drug-likeness of the selected ligands were also calculated. Findings demonstrated that NDL significantly (p <0.05) dose-dependently lessens the mean number of retches and delays the emetic onset in the chicks. The combined drug therapy with ondansetron exposed better antiemetic activity. In addition, in silico analysis, NDL has greater binding affinity (-7.3 kcal/mol) against M₂ and M₃ receptors. In conclusion, NDL exerted mild antiemetic activity with synergistic properties through muscarinic receptors.