Antibacterial properties of propolis and products containing propolis from Brazil

Crude propolis and commercial products containing propolis, such as ethanolic extracts, tablets, capsules and powders acquired in São Paulo City (Brazil) were analyzed. The resins of the solid products were extracted with ethanol and found to be present at various concentrations, independently of the propolis concentration specified on the label of the commercial products. The in vitro activity of these resins against S aureus, B cereus and B subrilis was also determined. The results showed that the antibacterial activity rather than the propolis concentration itself should be considered for quality control and that some resins are likely to display a species-specific action.