Green Nanotechnology Approach: Comparative Evaluation of Silver Nanoparticles from Two Plant Species and Three Solvent Systems

Introduction: Green synthesis using plant extracts provides an eco-friendly alternative to conventional nanoparticle production, reducing the use of toxic reagents while stabilizing particle surfaces. This study aimed to synthesize silver nanoparticles (AgNPs) using two plant species extracts and evaluate their antioxidant and antimicrobial potentials. Methods: The plant was extracted with 70% methanol, 70% ethanol, and distilled water. Extracts were mixed with 1 mM AgNO₃ solution at 25 °C for 24 h to synthesize AgNPs. The total phenolic content was measured using the Folin–Ciocalteu method, expressed as gallic acid equivalents. Antimicrobial activity was assessed against seven bacterial and three yeast strains using agar well diffusion, and minimum inhibitory, bactericidal, and fungicidal concentrations were determined by microdilution following CLSI standards. Results: The findings revealed that solvent type significantly influenced both the total phenolic content of the extracts and the physicochemical properties of the synthesized nanoparticles. Higher phenolic content was associated with enhanced stability and improved antimicrobial efficacy. Notably, AgNPs synthesized with ethanol extracts demonstrated stronger antibacterial activity, whereas those produced with aqueous extracts showed relatively lower bioactivity. Conclusions: The plant extract can act as a natural reducing and capping agent for green synthesis of silver nanoparticles. Although free extracts lacked antimicrobial activity, AgNP-enriched extracts displayed broad-spectrum antibacterial and antifungal effects while retaining measurable antioxidant capacity. These findings suggest that plant-based AgNPs offer an environmentally friendly and biocompatible approach for enhancing the biological efficacy of phytochemicals and hold promise for biomedical applications.