title: In vitro antimicrobial activity of propolis and synergism between propolis and antimicrobial drugs.
abstract: The aim of this study was to investigate antimicrobial properties of ethanolic extract of 13 propolis (EEP) samples from different regions of Serbia against 39 microorganisms (14 resistant or multiresistant to antibiotics), and to determine synergistic activity between antimicrobials and propolis. Antimicrobial activity of propolis samples was evaluated by agar diffusion and agar dilution method. The synergistic action of propolis with antimicrobial drugs was assayed by the disc diffusion method on agar containing subinhibitory concentrations of propolis. Obtained results indicate that EEP, irrespectively of microbial resistance to antibiotics, showed significant antimicrobial activities against Gram-positive bacteria (MIC 0.078%-1.25% of EEP) and yeasts (0.16%-1.25%), while Gram-negative bacteria were less susceptible (1.25%-->5%). Enterococcus faecalis was the most resistant Gram-positive bacterium, Salmonella spp. the most resistant Gram-negative bacteria, and Candida albicans the most resistant yeast. EEP showed synergism with selected antibiotics, and displayed ability to enhance the activities of antifungals. The shown antimicrobial potential of propolis alone or in combination with certain antibiotics and antifungals is of potential medical interest.
authors.affiliation: Department of Bacteriology, Institute of Microbiology and Immunology, School of Medicine, University of Belgrade, Dr Subotića 1, 11000 Belgrade, Serbia. stepan@afrodita.rcub.bg.ac.yu
authors.forename: Srdjan
authors.initials: S
authors.lastname: Stepanović
authors.forename: Natasa
authors.initials: N
authors.lastname: Antić
authors.forename: Ivana
authors.initials: I
authors.lastname: Dakić
authors.forename: Milena
authors.initials: M
authors.lastname: Svabić-Vlahović
mesh_terms: D000900:Anti-Bacterial Agents / Q000494:pharmacology*; D000890:Anti-Infective Agents / Q000494:pharmacology*; D002175:Candida / Q000187:drug effects*; D024881:Drug Resistance, Bacterial; D004357:Drug Synergism; D006090:Gram-Negative Bacteria / Q000187:drug effects*; D006094:Gram-Positive Bacteria / Q000187:drug effects*; D006801:Humans; D008826:Microbial Sensitivity Tests; D011429:Propolis / Q000494:pharmacology*
chemical_list: D000900:Anti-Bacterial Agents; D000890:Anti-Infective Agents; D011429:Propolis