Antibacterial potential of Swiss honeys and characterisation of their bee-derived bioactive compounds.

Abstract

Antibacterial activity of honey is not only crucial characteristic in selection of honey for medical usage but also an important honey quality marker. The aim of the study was to characterise the antibacterial potential of 29 honey samples representing the main types of multi-floral blossom and honeydew honeys produced in Switzerland. Antibacterial activity against Staphylococcus aureus and Pseudomonas aeruginosa was expressed as a minimum inhibitory and bactericidal concentrations (MIC and MBC). Furthermore, the content of bee-derived glucose oxidase (GOX) and its enzymatic product, H2 O2 , were also evaluated. All honey samples successfully met basic defined criteria (moisture and hydroxymethylfurfural (HMF)) tested in this study. Honeydew honeys were the most effective honey samples and generated the highest levels of H2 O2 . A strong significant correlation was found between the overall antibacterial activity and the level of H2 O2 among all honey samples. Interestingly, the content of GOX in honey samples did not correlate with their antibacterial activity as well as H2 O2 production capacity. A weak antibacterial activity was determined in five floral honeys, most likely due to increased enzymatic activity of pollen-derived catalase. This study showed that antibacterial effect of Swiss honey samples is associated mainly with H2 O2 . © 2019 Society of Chemical Industry.