Background and Aim: Propolis is one of the most important bee products used as a natural antibiotic alternative for industrial antibiotic production in order to reduce unnecessary usage of antibiotics. The chemical structure of this natural product in different regions of the world is different. The solvent used for extraction of propolis can have a significant impact on its antimicrobial activity. The purpose of this study was to evaluate the antimicrobial properties of ethanol and oil extracts of propolis produced in Kurdistan Province on Staphylococcus epidermidis, Streptococcus mutans and Entrobacter aerogenes.

Material and Methods: After collecting propolis from different parts of Kurdistan Province, ethanol and oil extracts were prepared. Minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) for the three above mentioned strains of bacteria were determined by using broth dilution method.

Results: Use of alcoholic solvent (96% ethanol and dimethyl sulfoxide) resulted in a greater mean diameter of growth inhibitory zone in comparison to oil extract (p<0.01). Inhibitory concentrations (MICs) of alcoholic extract of propolis for Staphylococcus epidermidis PTCC1435, Streptococcus mutans PTCC1683 and Enterobacter aerogenes PTCC1221 were 0.16, 0.32 and 0.65 mg/ml respectively. The MBCs, were 0.65, 1.31and 1.31 mg/ml respectively. The MICs of oil extract of propolis for Staphylococcus epidermidis PTCC1435, Streptococcus mutans PTCC1683 and Enterobacter aerogenes PTCC1221 were 2.62, 1.31 and 1.31 mg/ml and the MBCs for each of the above mentioned bacteria were 2.62.

Conclusion: Propolis showed significant antimicrobial effects in our study therefore, it can be used in the food and pharmaceutical industries.

Keywords: Propolis, Minimal inhibitory ioncentration (MIC), Minimum bactericidal concentration (MBC), Staphylococcus epidermidis, Streptococcus mutans, Enterobacter aerogenes.

Received: Jan 11, 2016      Accepted: Feb 12, 2016