title: Synergistic effects of honey and propolis toward drug multi-resistant Staphylococcus aureus, Escherichia coli and Candida albicans isolates in single and polymicrobial cultures.
abstract: BACKGROUND
  Propolis and honey are natural bee products with wide range of biological and medicinal properties. The study investigated antimicrobial activity of ethyl alcohol extraction of propolis collected from Saudi Arabia (EEPS) and from Egypt (EEPE), and their synergistic effect when used with honey. Single and polymicrobial cultures of antibiotic resistant human pathogens were tested.
  
  
  METHODS
  Staphylococcus aureus (S. aureus),), Escherichia coli (E. coli) and Candida albicans (C.albicans) were cultured in 10-100% (v/v) honey diluted in broth, or 0.08-1.0% (weight/volume) EEPS and EEPE diluted in broth. Four types of polymicrobial cultures were prepared by culturing the isolates with each other in broth (control) and broth containing various concentrations of honey or propolis. Microbial growth was assessed on solid plate media after 24 h incubation.
  
  
  RESULTS
  EEPS and EEPE inhibited antibiotic resistant E.coli, and S.aureus, and C.albicans in single and polymicrobial cultures. S.aureus became more susceptible when it was cultured with E.coli or C.albicans or when all cultured together. C.albicans became more susceptible when it was cultured with S.aureus or with E.coli and S. aureus together. The presence of ethyl alcohol or honey potentiated antimicrobial effect of propolis toward entire microbes tested in single or polymicrobial cultures. EEPS had lower MIC toward E.coli and C.albicans than EEPE. When propolis was mixed with honey, EEPS showed lower MIC than EEPE. In addition, honey showed lower MIC toward entire microbes when mixed with EEPS than when it was mixed with EEPE.
  
  
  CONCLUSIONS
  1) propolis prevents the growth of the microorganisms in single and mixed microbial cultures, and has synergistic effect when used with honey or ethyl alcohol, 2) the antimicrobial property of propolis varies with geographical origin, and 3) this study will pave the way to isolate active ingredients from honey and propolis to be further tested individually or in combination against human resistant infections.
authors.affiliation: Department of Plant Protection, College of Food and Agricultural Sciences, King Saud University-Riyadh, Kingdom of Saudi Arabia. Drnoori6@yahoo.com
authors.forename: Noori
authors.initials: N
authors.lastname: Al-Waili
authors.forename: Ahmad
authors.initials: A
authors.lastname: Al-Ghamdi
authors.forename: Mohammad Javed
authors.initials: MJ
authors.lastname: Ansari
authors.forename: Y
authors.initials: Y
authors.lastname: Al-Attal
authors.forename: Khelod
authors.initials: K
authors.lastname: Salom
mesh_terms: D000900:Anti-Bacterial Agents / Q000494:pharmacology*; D000935:Antifungal Agents / Q000494:pharmacology*; D002176:Candida albicans / Q000187:drug effects* / Q000302:isolation & purification; D024901:Drug Resistance, Multiple, Bacterial; D026141:Drug Resistance, Multiple, Fungal; D004357:Drug Synergism; D004534:Egypt; D004926:Escherichia coli / Q000187:drug effects* / Q000302:isolation & purification; D000431:Ethanol / Q000494:pharmacology; D006722:Honey; D006801:Humans; D008826:Microbial Sensitivity Tests; D011429:Propolis / Q000494:pharmacology*; D012529:Saudi Arabia; D013211:Staphylococcus aureus / Q000187:drug effects* / Q000302:isolation & purification
chemical_list: D000900:Anti-Bacterial Agents; D000935:Antifungal Agents; D000431:Ethanol; D011429:Propolis
keywords: Fungi; Honey; Propolis; bacteria; synergism.