Green synthesis and characterization of honey-mediated silver nanoparticles

Abstract

This study evaluated the physicochemical parameters of different honey samples produced in the lower Amazon region, including pH, soluble solids content, moisture, reducing sugars, and phenolic and biochemical compounds such as antioxidant and antimicrobial activity. The honeys with better antimicrobial activities were used to synthesize green silver nanoparticles (Ag-NPs). Most of the samples did not meet Brazilian standards for one or more physical–chemical parameters, but they did show high antioxidant activity and levels of phenolic compounds above 30 mgGA100g⁻¹. Approximately 50% of the honey samples exhibited antimicrobial activity against at least one microorganism tested (Staphylococcus aureus, Staphylococcus epidermidis, Escherichia coli and Candida kruzei). The synthesized AgNPs had a negative Zeta potential, and Ag-NP-14 and Ag-NP-15 had smaller hydrodynamic diameters (DH) and polydispersion index (PdI). The Ag-NPs demonstrated bacteriostatic and bactericidal activity against Escherichia coli and Staphylococcus aureus. Therefore, the green synthesis of Ag-NPs using different honeys could be an efficient and economical alternative to combat multiresistant bacteria. Green synthesis of nanoparticles, including silver nanoparticles, is a novel approach that involves using natural and eco-friendly sources, such as plant extracts, microorganisms, or natural compounds, to reduce and stabilize metal ions into nanoscale particles. The novelty of this method lies in its sustainable and environmentally friendly nature, avoiding the use of hazardous chemicals typically employed in traditional synthesis methods.