Abstract

Currently, there is a global interest in propolis research due to its various biological activities. In vitro methods are useful for preliminary investigation of the antibacterial activity of propolis extracts. The disk diffusion method and broth macrodilution method recommended by the Clinical and Laboratory Standards Institute were used in this study, with some modifications, to evaluate the antibacterial activity of propolis. Staphylococcus aureus ATCC 25923, Pseudomonas aeruginosa ATCC 27853 and Streptococcus pneumoniae ATCC 49619 were used. A standardized extract of Brazilian propolis was evaluated. The methods were precise and showed 100% accuracy. Gram positive bacteria were more sensitive to propolis extract than Gram negative bacterium. The validations demonstrated that the disk diffusion method and broth macrodilution method are appropriate for the evaluation of the antibacterial activity of propolis extracts. Therefore, the methodologies validated in this study may be useful tools in propolis research.

Key words: Methodologies, validation, antibacterial activity, propolis.

Abbreviation

CLSI, Clinical and laboratory standards institute; MIC, minimum inhibitory concentration; EPP-AF^Ò, Propolis standardized extract; RSD, relative standard deviation;MBC, minimum bactericidal concentration; SD, standard deviation.