Royal jelly: A novel eco-friendly biotemplate for the sustainable green synthesis of antibacterial silver, iron, copper, and zinc nanoparticles

This study explored the potential of royal jelly as an eco-friendly bio-reducing agent for synthesizing silver, iron, copper, and zinc nanoparticles and assessed their antibacterial properties. The nanoparticle synthesis was assessed by defining zeta-potential, particle size, and polydispersity and evaluated through Fourier Transform Infrared Spectroscopy (FTIR), ultraviolet-visible (UV-Vis), fluorescence emission, and transmission electron microscopy (TEM). The antibacterial activity of nanoparticles was examined by agar disc inhibition zone, minimum inhibitory concentrations (MIC), minimum bactericidal concentrations (MBC), scanning electron microscope (SEM), and Raman spectroscopy. FTIR indicates that the royal jelly protein is responsible for nanoparticle generation. Nanoparticles exhibit large negative zeta potential, with microscale polydisperse particle size. Nanoparticles increase UV light absorbance and reduce the fluorescence emission of royal jelly. TEM confirmed the formation of spherical and clustered nanostructures in nanoparticles. Royal jelly displays weak while royal jelly-synthesized nanoparticles display strong antibacterial activity. SEM and Raman spectroscopy confirmed morphological changes in the bacterial cell wall and membrane by nanoparticles. This research emphasizes the role of royal jelly as an eco-friendly reducing agent in sustainable antibacterial nanoparticle synthesis for applications in the food industry to extend shelf life, improve food packaging, and enhance food safety by inhibiting pathogen growth.