Synergy Between Silver Nanoparticles and Allium cepa Extract: A New Era in Antifungal Treatments

An eco‐friendly and biocompatible onion ( Allium cepa ) extract is proposed as a support for silver nanoparticles (AgNPs) to develop a highly effective antifungal agent against Trichophyton mentagrophytes at low concentrations. AgNPs with an average diameter of 16 ± 10 nm were successfully synthesized, achieving complete (100%) fungal inhibition at a concentration of 0.016 mg/mL. Ac ext ( A. cepa extract) was obtained, exhibiting a minimum inhibitory concentration (MIC) of 4.71 mg/mL and demonstrating complete fungal inhibition. The antifungal activity of AgNPs and Ac ext was evaluated, revealing that nanotechnology outperforms plant extracts, yielding promising results that suggest a safe alternative for antifungal treatments. To enhance antifungal efficacy, Ac ext was functionalized with AgNPs, yielding Ac ext –AgNPs. Using an Ac ext concentration of 0.64 mg/mL (75% below its MIC) and AgNPs at 0.0109 mg/mL (32% below its MIC), 97.92% inhibition of T. mentagrophytes was achieved. The synergistic interaction between Ac ext and AgNPs enabled potent antifungal activity at sub‐MIC concentrations of both components, highlighting their potential as an innovative and efficient antifungal treatment.