A novel green synthesis of gold nanoparticles using Syrian bee bread extract: phytochemical analysis, characterization, antimicrobial activity and biocompatibility

This study investigates the bioactive composition of Syrian bee bread (SBB) and its application in the green synthesis of gold nanoparticles (AuNPs). For the first time, bee bread was utilized for the synthesis of AuNPs. The SBB extract exhibited high levels of phenolic and flavonoid compounds. High-performance liquid chromatography (HPLC) identified key phenolic flavonoid, and sugar components, while Gas chromatography-mass spectrometry (GC-MS) revealed various bioactive constituents. The synthesis was optimized at pH 9.5, gold salt concentration of 2 mM, SBB extract 1%, and room temperature, yielding small, stable and well-dispersed AuNPs with Z-average of 46.38 ± 6.12 nm, polydispersity index (PDI) of 0.235 ± 0.002, and ζ-potential of − 29.7 mV according to Dynamic Light Scattering (DLS). Ultraviolet-visible spectroscopy (UV-Vis) showed a Localized surface plasmon resonance (LSPR) peak at 524 nm. Atomic Force Microscopy (AFM) and Field Emission Scanning Electron Microscopy (FESEM) confirmed spherical nanoparticles, with sizes of ~ 33 nm and ~ 28.69 nm, respectively. The SBB-AuNPs displayed antimicrobial activity against Pseudomonas aeruginosa, Escherichia coli, Klebsiella Spp., and Candida albicans, with inhibition zones ranging from 18 to 27 mm. Importantly, no cytotoxic effects were observed in normal fibroblast cells at concentrations below 100 µg/mL indicating promising biocompatibility. This novel approach yields small, stable, and bioactive nanoparticles with potent antimicrobial properties and high biocompatibility, representing a significant improvement over other bee product-based methods. These findings highlight the potential biomedical applications of SBB-AuNPs, including their incorporation into topical creams or ointments for the prevention and treatment of skin infections, wound-healing formulations, and as antimicrobial agents in medical devices or protective coatings.