Imidazole clubbed 1,3,4-oxadiazole derivatives as potential antifungal agents.

A series of compounds in which 2-(4-ethyl-2-pyridyl)-1H-imidazole was clubbed with substituted 1,3,4-oxadiazole was synthesized and subjected to antifungal activity evaluation. In vitro assays indicated that several clubbed derivatives had excellent antifungal activity against different strains of laboratory and clinically isolated Candida species. Structural Activity Relationship (SAR) studies revealed that the presence and position of substituents on the phenyl ring of the 1,3,4-oxadiazole unit, guides the antifungal potential of the compounds, where compound 4b, 4c and 4g were found to be active against all the tested fungal strains. Impairment of ergosterol biosynthesis upon the concomitant treatment of 4b, 4c and 4g, revealed the possible mechanisms of antifungal action of these compounds. Inhibitors snugly fitting the active site of the target enzyme, as revealed by molecular docking studies, may well explain their excellent inhibitory activity.

Biogenic silver nanoparticles using Rhinacanthus nasutus leaf extract: synthesis, spectral analysis, and antimicrobial studies.

Nanotechnology is gaining momentum due to its ability to transform metals into nanoparticles. The synthesis, characterization, and applications of biologically synthesized nanomaterials have become an important branch of nanotechnology. Plant extracts are a cost-effective, ecologically friendly, and efficient alternative for the large-scale synthesis of nanoparticles. In this study, silver nanoparticles (AgNps) were synthesized using Rhinacanthus nasutus leaf extract. After exposing the silver ions to the leaf extract, the rapid reduction of silver ions led to the formation of AgNps in solution. The synthesis was confirmed by ultraviolet-visible spectroscopy, Fourier transform infrared spectroscopy, and transmission electron microscopy. The in vitro antimicrobial activity of the AgNps synthesized using R. nasutus leaf extract was investigated against Bacillus subtilis, Staphylococcus aureus, Pseudomonas aeruginosa, Klebsiella pneumonia, Escherichia coli, Aspergillus niger, and Aspergillus flavus using a disc diffusion method. The AgNps showed potential activity against all of the bacterial strains and fungal colonies, indicating that R. nasutus has the potential to be used in the development of value-added products in the biomedical and nanotechnology-based industries.