Antibacterial activity of honeys from Amazonian stingless bees of Melipona spp. and its effects on bacterial cell morphology

BACKGROUND The stingless bee honey has great therapeutic potential, especially as an antimicrobial agent. In this study, we evaluate the in vitro antibacterial potential of honey from Melipona spp. with occurrence in Rio Branco-AC and Xapuri-AC from Amazonian region. Samples were collected from the species Melipona eburnea, (ME), M. grandis (MG), M. flavolineata (MF) and M. seminigra (MS). The antibacterial activity of the honey samples was tested against standard Gram-positive and Gram-negative bacteria and two strains isolated from bovine mastitis. RESULTS We observed antibacterial activity for the four honeys against the tested strains, in the agar diffusion assay. The MF honey showed Minimmum Inhibitory Concentration (MIC) lower than 3.12% (v/v). The Minimum Bactericidal Concentration (MBC) values were bigger than the MIC for most of the microorganisms tested. Scanning electron microscopy (SEM) showed the damage effect of the honey of M. flavolineata to S. aureus cells, and its inhibitory effect on cell division. CONCLUSION This study demonstrated that the stingless bees' honey possesses in vitro antimicrobial activity against pathogenic bacteria. The effects observed in SEM, makes honey from Amazonian stingless bee M. flavolineata a promissing product as a potential antimicrobial agent for use in therapeutic approaches in the future. This article is protected by copyright. All rights reserved.