Biosynthesis of Silver Nanoparticles Using Licorice Extract and Evaluation of their Antioxidant Activity

This paper presents a simple and eco-friendly method for the synthesis of silver nanoparticles (AgNPs) using licorice (Glycyrrhiza glabra) root extract and the evaluation of their antioxidant activity. UV- Vis spectroscopy, FTIR, TEM and EDX methods were used to characterize the AgNPs. The UV-Vis spectrum shows the characteristic surface plasmon resonance peak at 430 nm. The synthesized AgNPs have a spherical shape and are capped by biomolecules. Furthermore, FTIR spectra and EDX analysis demonstrate the presence of phytochemicals from extract which act as reducing and stabilizing agents. The presence of elemental silver was demonstrated by the peak at 3 keV from EDX spectra. The results following the DPPH free radical scavenging assay suggest that AgNPs present a better antioxidant activity compared to that of the extract. Therefore, the obtained results confirm that licorice represents a source of biomolecules that can be used for synthesizing AgNPs with antioxidant potential.