Synergistic effect of Salvadora persica and chitosan nanoparticles against oropharyngeal microorganisms.

Herbal medicine combined with nanoparticles has caught much interest in clinical dental practice, yet the incorporation of chitosan with Salvadora persica (S. persica) extract as an oral care product has not been explored. The aim of this study was to evaluate the combined effectiveness of Salvadora persica(S. persica) and Chitosan nanoparticles (ChNPs) against oropharyngeal microorganisms. Agar well diffusion, minimum inhibitory concentration, and minimal lethal concentration assays were used to assess the antimicrobial activity of different concentrations of ethanolic extracts of S. persica and ChNPs against selected fungal strains, Gram-positive, and Gram-negative bacteria. A mixture of 10% S. persica and 0.5% ChNPs was prepared (SChNPs) and its synergistic effect against the tested microbes was evaluated. Furthermore, the strain that was considered most sensitive was subjected to a 24-h treatment with SChNPs mixture; and examined using SEM, FT-IR and GC-MS analysis. S. persica extract and ChNPs exhibited concentration-dependent antimicrobial activities against all tested strains. S. persica extract and ChNPs at 10% were most effective against S. pneumoni, K. pneumoni, and C. albicans. SEM images confirmed the synergistic effect of the SChNPs mixture, revealing S. pneumonia cells with increased irregularity and higher cell lysis compared to the individual solutions. GC-MS and FT-IR analysis of SChNPs showed many active antimicrobial phytocompounds and some additional peaks, respectively. The synergy of the mixture of SChNPs in the form of mouth-rinsing solutions can be a promising approach for the control of oropharyngeal microbes that are implicated in viral secondary bacterial infections.

Synthesis and anticancer activity of some novel fused pyridine ring system.

New series of pyrido[3',2':4,5]thieno[3,2-d]pyrimidines (7a,b) and thieno[2,3-b:4,5-b'] dipyridine (11a-c) were synthesized from 4-aryl-6-(4-chlorophenyl)-2-thioxo-1,2-dihydro pyridine-3-carbonitriles 4a,b via application of Thorpe-Zielger reaction. The novel target compounds were evaluated in vitro for their anticancer activity against human breast adenocarcinoma MCF-7 and colon carcinoma cell line (HCT 116). Most of the tested compounds exploited potent to moderate growth inhibitory activity, in particular compound 11d, which exhibited superior potency to the reference drug Doxorubicin (IC(50) = 5.95, 6.09 and 8.48, 8.15 µM, respectively). The structures of the compounds obtained were determined by spectroscopic data.