Antimicrobial activity of bacterial isolates from different floral sources of honey.Int J Food Microbiol. 2008 Aug 15; 126(1-2):240-4.IJ
More than two thousand bacterial strains isolated from six US domestic honeys and two manuka honeys from New Zealand were screened for production of antimicrobial compounds. A high incidence of antimicrobial inhibition determined by deferred inhibition assays was observed with the bacterial isolates from all eight honey samples. In total, 2217 isolates out of 2398 strains (92.5% of total isolates) exhibited antimicrobial activity against at least one of the tested microorganisms. Antifungal activity by bacterial isolates originating from the eight honeys ranged from 44.4% to 98.0%. Bacterial isolates from manuka honey (MH1) exhibited antimicrobial activity against Bacillus subtilis ATCC 6633 and Bacillus cereus F4552, at 51.5% and 53.3% of the isolates, respectively. However, less than 30% of the bacterial isolates from the other manuka honey (MH2) and six domestic honey sources exhibited anti-Bacillus activity. Listeria monocytogenes F2-586 1053 showed higher overall rates of sensitivity to between 11 and 66% of the bacterial isolates. The high rate of antimicrobial activity exhibited by the bacterial strains isolated from different honey sources could provide potential sources of novel antimicrobial compounds.