Evaluation of the microbiological quality of some natural honeys and determination of their antibacterial activity.

Antibiotic resistance is a major concern for health systems worldwide, due to the irrational use of antibiotics. Honey can be considered an alternative therapy to antibiotics. Our study aims to evaluate the microbiological quality and presumed antibacterial activity of 7 natural honeys of different floral origins. Aerobic bacteria grew in 3 samples of honey: (jujube honey ( Bacillus subtilis ), fig honey ( Staphylococcus hominis , S. epidermidis, and S. pettenkoferi ) and holm oak honey ( Aerococcus viridans )). Only holm oak honey contained a yeast ( Cryptococcus neoformans ), while the other honeys were free of yeasts and molds. Holm oak honey was most effective on most bacterial strains studied, particularly S. pyogenes . The other honeys were mainly active against S. pyogenes . None of the honeys showed activity against P. aeruginosa , K. pneumoniae , S. aureus and C. albicans . The MIC was 25% for holm oak honey against the 5 bacterial strains which showed a response. For fig honey, the MIC varied between 50% ( S. pyogenes , S. aureus and S. epidermidis ) and 100% ( S. hominis and E. coli ). For most other honeys, the MIC was 100%, meaning only the pure form of honey could prevent bacterial growth. In this study, honey, consistent with its traditional use in the ENT sphere, was found to be effective against S. pyogenes , a bacteria often responsible for bacterial tonsillitis which can limit the inappropriate use of antibiotics. These results could guide pharmaceutical research aimed at extracting active ingredients from honey to develop new antibacterial agents.