Green Synthesis of Silver Nanoparticles Using Eremerus luteus Extract (Ag@ELL): Evaluation of Antioxidant, Antibacterial, and Anti-Biofilm Effects Against Enterococcus faecalis with Promising Applications in Endodontics

Background: Antibiotic-resistant pathogens and persistent biofilms present major challenges in endodontic therapy. This study synthesized silver nanoparticles using Eremerus luteus leaf extract (Ag@ELL) through a green approach and evaluated their physicochemical properties and antimicrobial potential against Enterococcus faecalis and other oral pathogens. Methods: Ag@ELL nanoparticles were synthesized via plant-mediated reduction and characterized using spectroscopic and microscopic techniques. Antimicrobial activity was assessed by broth microdilution method, anti-biofilm efficacy was evaluated by crystal violet assay, and antioxidant activity was determined using the DPPH method. Results: Characterization analyses confirmed the successful formation of predominantly spherical Ag@ELL nanoparticles (20–30 nm), and FTIR results validated the involvement of phytochemicals as reducing and stabilizing agents. Ag@ELL nanoparticles demonstrated potent antimicrobial activity, effectively eradicating up to 86.2% of E. faecalis biofilms. Additionally, they exhibited strong, dose-dependent antioxidant activity. Conclusion: Ag@ELL nanoparticles present a promising eco-friendly candidate for endodontic applications due to their multifunctional bioactivity. Their green synthesis route and potent biological effects warrant further investigation for potential clinical translation.