Synthesis of a Novel Sepiolite–Ag–Propolis Nanocomposite and Its Effect on the Growth of <i>Aspergillus flavus</i>

Since aflatoxin produced by <i>Aspergillus flavus</i> carries significant impacts on the livestock and poultry industries in terms of animal health and food safety. It is very important to find nonchemical antifungal agents. For this purpose, in this study, bee propolis and its nanocomposites with sepiolite and Ag nanoparticles were investigated for antifungal activity with respect to their use as safer alternatives for conventional antifungal treatments. In the present study, two newly synthesized sepiolite-propolis and sepiolite-Ag-propolis nanocomposite formulations were characterized with different analytical techniques such as XRD, TEM, FTIR, and EDAX. The antifungal potential was determined against <i>A. flavus</i> by the disc diffusion method, and MIC-MFC values were determined. The pure propolis extract had only limited antifungal activity at concentrations up to 400 mg/mL. However, prominent antifungal activities were observed for nanocomposites with propolis, sepiolite, and Ag nanoparticles, as inhibition was observed even at a low concentration of 200 mg/mL. The sepiolite-Ag-propolis nanocomposite outperformed others by increasing the diameter of inhibition zones proportionally with the increase in concentration. The finding results indicate that propolis-based nanocomposites, especially when combined with Ag nanoparticles, hold a promise for antifungal action against <i>A. flavus</i>. Further work is necessary to test their practical value in agricultural and food safety contexts.