Eco-Friendly Green Synthesis of Silver Nanoparticles from Egyptian Honey: Evaluating its Antibacterial Activities

Abstract

THIS RESEARCH article describes a strong approach for the green synthesis of silver nanoparticles (AgNPs) that employs a local black seed honey (BSH). Honey was chosen as the eco-friendly reducing and stabilizing agent replacing most reported reducing agents which represent highly biological risk to the society and environment. Honey reduced silver ions into AgNPs after 20min in a stirred reaction mixture. Nanoparticles of different sizes were obtained, and the solution turned black over time. The antibacterial activity of AgNPs was investigated against eight pathogenic bacterial strains; five Gram-negative and three Gram-positive. AgNPs were potentially effective against the Gram-negative more than Gram-positive bacterial strains. E. coli and P. aeruginosa were the highly susceptible strains with 6.3μg/ml minimum inhibitory concentrations (MICs). The AgNPs were characterized by perform UV-visible spectroscopy, fourier transform infrared spectroscopy (FTIR), transmission electron microscopy (TEM) and scanning electron microscopy (SEM) imaging. The colloid obtained at a pH of 9 was found to be spherical in shape and was distributed with a certain amount of agglomeration. An intense surface plasmon resonance band at 400nm in the UV-visible spectrum clearly revealed the formation of AgNPs after 72hr. TEM showed spherically shaped AgNPs, and the sizes of the nanoparticles ranged from 25-70nm. AgNPs had broad spectrum antibacterial property thus it can be explored further for medical and therapeutic applications.