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111.
The aim of this study was to investigate the antimycobacterial activity of the major daucane constituent, ferutinin (jaeschkeandiol p-hydroxybenzoate, 1), four of its natural analogues, its hydrolysis products, as well as methyl p-hydroxybenzoate (methylparaben) against Mycobacterium smegmatis, a rapidly growing surrogate of Mycobacterium tuberculosis. The agar dilution assay was utilised for an antimycobacterial evaluation of single compounds. A modified agar dilution assay, the checkerboard method, was utilised for evaluating the potentiating effect of 1 on different antitubercular drugs, namely isoniazid, ethionamide, rifampin and streptomycin. In the agar dilution assay, 1 exhibited higher potency (minimum inhibitory concentration [MIC] 10?μg?mL?1) than streptomycin and rifampin (MIC 20?μg?mL?1 for each). Of the natural analogues, 8,9-epoxyjaeschkeandiol p-hydroxybenzoate and 8,9-epoxyjaeschkeandiol benzoate exhibited marginal activity (MIC?≥?40 and 80?μg?mL?1, respectively). The checkerboard method showed that the combination of 1 with each antitubercular drug led to mutual enhancement of the antimycobacterial activity with isoniazid and ethionamide, while no such effect was observed with rifampin or streptomycin. Based on this study and earlier studies with Staphylococcus aureus, the major constituent 1 may be responsible for the major part of the antimicrobial activity of the root of Ferula hermonis. 相似文献
112.
Two new phytochemical compounds, Tetranins A and B, 1-(3,5'-dihydroxy-4'-méthoxyphenyl)-2-phenylethanol 1 and 5,2'-dihydroxy-5'-methoxy-6,7-methylenedioxy-isoflavone 2, were isolated from the EtOAc extract of Salsola tetrandra roots. They exhibited a significant antioxidant effect in 1,1-diphenyl-2-picrylhydrazyl (DPPH) free radical and 2,2'-azinobis (3-ethylbenzothiazoline-6-sulphonic acid (ABTS) assays. Their structures were elucidated by extensive spectroscopic methods including 1-D-((1)H and (13)C) and 2-D-NMR experiments (CHcorr, HMBC, (1)H-(1)H COSY and NOESY) as well as high-resolution ES-MS and they were found to be quite active as antioxidants in the DPPH and ABTS assays. 相似文献
113.
Asif Hayat Muhammad Sohail Atef El Jery Khadijah M. Al-Zaydi Khaled F Alshammari Javid Khan Hamid Ali Zeeshan Ajmal T. A. Taha Israf Ud Din Rashid Altamimi Mahmoud Ali Hussein Yas Al-Hadeethi Yasin Orooji Mohd Zahid Ansari 《Chemical record (New York, N.Y.)》2023,23(5):e202200171
Graphitic carbon nitride (g-C3N4) has gained tremendous interest in the sector of power transformation and retention, because of its distinctive stacked composition, adjustable electronic structure, metal-free feature, superior thermodynamic durability, and simple availability. Furthermore, the restricted illumination and extensive recombination of photoexcitation electrons have inhibited the photocatalytic performance of pure g-C3N4. The dimensions of g-C3N4 may impact the field of electronics confinement; as a consequence, g-C3N4 with varying dimensions shows unique features, making it appropriate for a number of fascinating uses. Even if there are several evaluations emphasizing on the fabrication methods and deployments of g-C3N4, there is certainly an insufficiency of a full overview, that exhaustively depicts the synthesis and composition of diverse aspects of g-C3N4. Consequently, from the standpoint of numerical simulations and experimentation, several legitimate methodologies were employed to deliberately develop the photocatalyst and improve the optimal result, including elements loading, defects designing, morphological adjustment, and semiconductors interfacing. Herein, this evaluation initially discusses different dimensions, the physicochemical features, modifications and interfaces design development of g-C3N4. Emphasis is given to the practical design and development of g-C3N4 for the various power transformation and inventory applications, such as photocatalytic H2 evolution, photoreduction of CO2 source, electrocatalytic H2 evolution, O2 evolution, O2 reduction, alkali-metal battery cells, lithium-ion batteries, lithium–sulfur batteries, and metal-air batteries. Ultimately, the current challenges and potential of g-C3N4 for fuel transformation and retention activities are explored. 相似文献
114.
Hayam Osman Taha Atef M. El Mahdy Fatma El Sayed El Shemy Mohammed Mohammed Hassan 《International journal of quantum chemistry》2023,123(3):e27023
Hydrogen is regarded as one of the most potential sustainable energy sources in the future. Applications include transportation. Still, the event of materials for its storage is difficult notably as a fuel in vehicular transport. Nanocones are a promising hydrogen storage material. Silicon, germanium, and tin carbide nanocones have recently been proposed as promising hydrogen storage materials. In the present study, we have investigated the hydrogen storage capacity of and nanocones functionalized with Ni. The functionalized Ni atom are found to be adsorbed on and with an adsorption energy of −5.56, −6.70, and −4.25 eV. The functionalized , and bind up to seven, six and four molecules of hydrogen with the adsorption energy of (−0.34, −0.35, and −0.26 eV) and an average desorption temperature of around 434, 447, and 332 K (ideal for fuel cell applications). The SiC, GeC, and SnC nanocones systems exhibit a maximum gravimetric storage capacity of 12.51, 7.78, and 4.08 wt%. We suggested that Ni SiCNC and Ni GeCNC systems can act as potential H2 storage device materials because of their higher H2 uptake capacity as well as their stronger interaction with adsorbed hydrogen molecules than Ni SnCNC systems. The hydrogen storage reactions are characterized in terms of the charge transfer, the partial density of states, the frontier orbital band gaps, and isosurface plots. And electrophilicity are calculated for the functionalized and hydrogenated and nanocones. 相似文献