Green Synthesis and Characterization of Silver and Gold Nanoparticles Using Echinophora platyloba Extract and Evaluation of Their Anti‐Inflammatory and Antioxidant Properties

This study intends to investigate the green synthesis of silver (Ag) and gold (Au) nanoparticles (NPs) using Echinophora platyloba extract and to evaluate the antioxidant and anti‐inflammatory effects of the synthesized NPs and the extract. In this study, aqueous and hydroalcoholic extracts of E. platyloba were prepared, which were used for the biosynthesis of Ag and Au NPs. Dynamic light scattering (DLS), zeta potential analysis, transmission electron microscopy (TEM), Fourier transform infrared (FT‐IR) spectroscopy, UV‐Vis spectroscopy, and X‐ray diffraction (XRD) methods were used to characterize the green NPs. The antioxidant effect of the NPs was estimated using in vitro methods, including reducing power (RP), ferric reducing/antioxidant power (FRAP), and 2,2‐diphenyl‐1‐picrylhydrazyl (DPPH). To evaluate the anti‐inflammatory and antioxidant activity of E. platyloba extract and Ag and Au NPs, we used the carrageenan method. In our experiment, the extract and the synthesized NPs were administered orally to the mice 2 h before the carrageenan injection. The subsequent inhibition of inflammation and reduction of paw thickness were quantified. To evaluate their antioxidant effect, malondialdehyde (MDA), and total antioxidant capacity (TAC) levels were measured. Levels of pro‐inflammatory cytokines, interleukin‐6 (IL‐6) and tumor necrosis factor‐ α (TNF‐ α ), were also quantified. In this study, the results indicate that the synthesized Ag and Au NPs have antioxidant and anti‐inflammatory effects. The most promising results were observed in the groups that received the Ag NPs.