Detection of antimicrobials in bee products with activity against viridansstreptococci

Objectives: Bee products have been studied extensively for their healing pr operties and have become part of cosmetic preparations and folk medicine. T he major objective of this study was to examine the presence of antimicrobi als in various bee products. Design: Propolis, honeycomb lids, pollen, honeycombs, and honey were screen ed for antimicrobial compounds. Viridans streptococci were used as indicato r strains. Ethanol extracts were applied onto paper disks, dried, and put o n the surface of nutrient agar plates with the overlay containing viridans streptococci. The plates were then incubated and evaluated the next day for the presence of inhibition zones. The size of the inhibition zone represen ted a quantitative measure of antimicrobial activity in a sample. Thin-laye r chromatography was used for separation of compounds in the samples and bi odetection-an overlay with indicator strain-identified the antimicrobial co mpounds by formation of inhibition zones. Results: Ethanol extracts of propolis and honeycomb lids, as well as honey containing honeycomb lids contained a mixture of antimicrobial compounds in various amounts. Thin-layer chromatography experiments with two different solvent systems differing in polarity suggested that major antimicrobials p resent in the samples prepared from honeycomb lids, honeycombs, pollen, and propolis have similar properties. These active compounds were not extremel y hydrophobic. Conclusions: Extracts from the tested samples of bee products exhibited ant imicrobial properties at various levels depending on the sample and bacteri al species used for testing. Using chromatographic techniques, we demonstra ted similar properties of the active compounds in various active samples. I n conclusion, our results suggest that honey containing honeycomb lids may be a beneficial food supplement because of the presence of antibacterial co mpounds.