The study on biological activities of silver nanoparticles produced via green synthesis method using Salvia officinalis and Thymus vulgaris

In the present study, Ag nanoparticles (AgNPs) were synthesized from Salvia officinalis and Thymus vulgaris, known as phytotherapy plants. The obtained silver nanoparticles were characterized using SEM, XRD, FTIR, and UV/Vis spectra. The antioxidant capacities of Salvia officinalis-mediated AgNP (SO-AgNP) and Thymus vulgaris-mediated AgNP (TV-AgNP) were analyzed in vitro using 1,1-diphenyl-2-picrylhydrazyl and iron chelating activity assays. DPPH activities were 83.74% and 57.17% for SO-AgNP and TV-AgNP at concentration 200 mg/L, respectively. Both green synthesized AgNPs exhibited good iron chelating activity. In addition, the DNA cleavage activities of SO-AgNPs and TV-AgNP were investigated with agarose gel electrophoresis technique. SO-AgNPs and TV-AgNP showed single-strand DNA cleavage activity. AgNPs showed that the SO-AgNP and TV-AgNp were effective against bacteria and fungi, and antimicrobic activities were assessed as minimal inhibition concentration (MIC). Remarkably, green synthesized AgNPs showed highly effective cell viability and biofilm inhibition effect. AgNPs also demonstrated slightly antimicrobial photodynamic activity after LED irradiation.