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31.
Samia Oueslati Ahlem Ellili Jean Legault Andre Pichette Riadh Ksouri Mokhtar Lachaal 《Natural product research》2015,29(12):1189-1191
This study investigates the polyphenol content of Diplotaxis simplex extract and the biological activities of the main organ. The analysed extracts showed that polyphenol contents varied considerably as a function of organs. Furthermore, novel biological activities of this species were assessed. Flower extracts exhibit a potent in vitro antioxidant capacity using oxygen radical absorbance capacity and displayed a strong anti-inflammatory activity, inhibiting nitric oxide release, by 79.3% at 160 μg/mL. Our findings suggested that the Diplotaxis flower is a valuable source of antioxidants and anti-inflammatory agents. 相似文献
32.
Sobia Mastoor Fizza Nazim Syed Rizwan-ul-Hasan Khalid Ahmed Shabnam Khan Syed Nawazish Ali Syed Hani Abidi 《Molecules (Basel, Switzerland)》2022,27(20)
(1) Background: Staphylococcus aureus (S. aureus) is one of the most frequent causes of biofilm-associated infections. With the emergence of antibiotic-resistant, especially methicillin-resistant S. aureus (MRSA), there is an urgent need to discover novel inhibitory compounds against this clinically important pathogen. In this study, we evaluated the antimicrobial and anti-biofilm activity of 11 compounds, including phenyl propenes and phenolic aldehydes, eugenol, ferulic acid, sinapic acid, salicylaldehyde, vanillin, cinnamoyl acid, and aldehydes, against drug-resistant S. aureus isolates. (2) Methods: Thirty-two clinical S. aureus isolates were obtained from Alkhidmat Diagnostic Center and Blood Bank, Karachi, Pakistan, and screened for biofilm-forming potential, and susceptibility/resistance against ciprofloxacin, chloramphenicol, ampicillin, amikacin, cephalothin, clindamycin, streptomycin, and gentamicin using the Kirby-Bauer disk diffusion method. Subsequently, 5 representative clinical isolates were selected and used to test the antimicrobial and anti-biofilm potential of 11 compounds using both qualitative and quantitative assays, followed by qPCR analysis to examine the differences in the expression levels of biofilm-forming genes (ica-A, fnb-B, clf-A and cna) in treated (with natural compounds and their derivatives) and untreated isolates. (3) Results: All isolates were found to be multi-drug resistant and dominant biofilm formers. The individual Minimum Inhibitory Concentration (MIC) of natural compounds and their analogues ranged from 0.75–160 mg/mL. Furthermore, the compounds, Salicylaldehyde (SALI), Vanillin (VAN), α-methyl-trans-cinnamaldehyde (A-MT), and trans-4-nitrocinnamic acid (T4N) exhibited significant (15–92%) biofilm inhibition/reduction percentage capacity at the concentration of 1–10 mg/mL. Gene expression analysis showed that salicylaldehyde, α-methyl-trans-cinnamaldehyde, and α-bromo-trans-cinnamaldehyde resulted in a significant (p < 0.05) downregulation of the expression of ica-A, clf-A, and fnb-A genes compared to the untreated resistant isolate. (4) Conclusions: The natural compounds and their analogues used in this study exhibited significant antimicrobial and anti-biofilm activity against S. aureus. Biofilms persist as the main concern in clinical settings. These compounds may serve as potential candidate drug molecules against biofilm forming S. aureus. 相似文献
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34.
Besma Mellah Rym Abidi Haiko Herchbach Kwanghyun No Jong Seung Kim Françoise Arnaud Hubscher Veronique 《Journal of inclusion phenomena and macrocyclic chemistry》2010,66(1-2):153-161
The binding properties of four amido derivatives of p-tetraphenyl tetrahomodioxacalix[4]arene towards alkali and alkaline-earth metal cations using UV-absorption spectrophotometry, 1H NMR and ESI-mass spectrometry techniques are reported. 相似文献
35.
This paper deals with the global well-posedness of the 3D axisymmetric Euler equations for initial data lying in critical
Besov spaces Bp,11+3/p{B_{p,1}^{1+3/p}}. In this case the BKM criterion is not known to be valid and to circumvent this difficulty we use a new decomposition of
the vorticity. 相似文献
36.
We consider a frictionless contact problem with unilateral constraints for a 2D bar. We describe the problem, then we derive its weak formulation, which is in the form of an elliptic variational inequality of the first kind. Next, we establish the existence of a unique weak solution to the problem and prove its continuous dependence with respect to the applied tractions and constraints. We proceed with the study of an associated control problem for which we prove the existence of an optimal pair. Finally, we consider a perturbed optimal control problem for which we prove a convergence result. 相似文献
37.
Dr. Khouloud Hchicha Dr. Noureddine Mhadhbi Dr. Ahlem Guesmi Dr. Taoufik Soltani Dr. Naoufel Ben Hamadi Prof. Houcine Naïli 《欧洲无机化学杂志》2023,26(13):e202200696
S-substituted La2Mo2O9 were synthesized by a solid-state procedure employing ammonium sulfate (NH4)2SO4 as a sulfur source. The synthesized powders were examined using X-ray diffraction (XRD), thermogravimetric analysis (TGA), infrared, and Raman spectroscopies. The results divulged that the stabilization of the β-La2Mo2O9 polymorph occurred in the interval of sulfur composition 0.1≤y≤0.6. This substitution generates a linear dwindling of the unit cell volume. The decomposition of all substituted samples started above 900 °C with a total weight loss linearly dependent on the sulfur content. Electrical studies confirmed that substituting S6+ for Mo6+ suppresses the phase transition of La2Mo2O9 and stabilizes the cubic polymorph down to ambient temperature. It was also remarkable that this substitution caused a decrease in the conductivity, and unfortunately, none of the tested compositions allowed exceeding the conductivity of La2Mo2O9. Infrared and Raman spectra confirmed the presence of the characteristic peaks of sulfates and molybdates groups. 相似文献
38.
Belkadi Ahlem Kenouche Samir Melkemi Nadjib Daoud Ismail Djebaili Rachida 《Structural chemistry》2022,33(3):833-858
Structural Chemistry - CHK1 is a promising molecular target that gained immense attention recently for the development of cancer therapeutics. In this study, a simulation-based investigation was... 相似文献
39.
Warke A. S. Ramesh K. Mebarek-Oudina F. Abidi A. 《Journal of Thermal Analysis and Calorimetry》2022,147(12):6901-6912
Journal of Thermal Analysis and Calorimetry - In this paper, we have investigated the two-dimensional magnetohydrodynamic steady boundary layer flow of a viscous magnetomicropolar liquid via an... 相似文献
40.