Antibacterial activity of Saudi honey against Gram negative bacteria

The antibacterial activity of local Sidr and Mountain Saudi honeys against Escherichia coli, Klebsiella pneumoniae, Pseudomonas aeruginosa and Acinetobacter baumannii were evaluated. Disc diffusion method, gel diffusion method, minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) values were used in this investigation. The findings indicated that both honey samples had growth inhibitory effect and all tested gram negative bacteria were sensitive to 40-80% concentrations. Increasing the honey concentration significantly (P≤0.05) increased the inhibition of growth of the tested bacteria. Sidr honey was more potent than Mountain honey in producing the inhibitory growth effect as an antibacterial agent. Sidr and Mountain honeys in different concentrations were more effective against E.coli than other bacteria. MIC of the two honey samples was 20 mg/mL while the MIC of K. pneumoniae was 40 mg/mL in the case of Mountain honey. The MBC of the two honey samples was 40 mg/mL and the MBC of A. baumannii that valued was 20 mg/mL. We are of the opinion that Sidr and Mountain Saudi honeys could potentially be used as therapeutic agents against bacterial infection particularly to the tested microorganisms.