فهرست نشریات علمی دسترسی آزاد ایران

In this research, gold nanoparticles (AuNPs) were synthesized for the first time utilizing the extract of Teucrium polium. The study evaluated the antimicrobial potential of both methanolic and aqueous extracts of T. polium, alongside the synthesized AuNPs. Furthermore, the impact of varying AuNP concentrations on the phytochemical characteristics of the plant extract was analyzed. The successful fabrication of AuNPs was verified through a comprehensive suite of characterization techniques, including UV-Vis spectroscopy, XRD, TEM, SEM, and FTIR. Morphological analysis via SEM and TEM revealed spherical nanoparticles with a mean diameter of 22.89 nm, while the UV-Vis spectrum exhibited a characteristic surface plasmon resonance (SPR) peak at 420 nm. The reaction reached its optimum efficiency at pH 5. Antimicrobial assays indicated that the methanolic extract possessed superior antibacterial and antifungal properties compared to the aqueous version, yielding maximum inhibition zones for Escherichia coli (14±1.4 mm) and Aspergillus niger (15±0.7 mm). Additionally, the AuNPs demonstrated notable efficacy against gram-negative bacteria, with the highest inhibition observed for E. coli (18±0.7 mm) and A. niger (20±0.9 mm). Regarding the antioxidant capacity and reducing power (phenolic flavonoid content), a concentration-dependent increase was observed up to 60 ppm (IC50=9.94 µg/mL; reducing power= 16.85 mMFe2+/mg sample), followed by a decline at concentrations exceeding this threshold.