title: In vitro synergistic effects of baicalin with oxytetracycline and tetracycline against Staphylococcus aureus.
abstract: OBJECTIVE
  In this study we examined the in vitro synergistic effect of baicalin, the flavone constituent of Scutellaria spp., in combinations with oxytetracycline and tetracycline on the growth of Staphylococcus aureus.
  
  
  METHODS
  The MICs were determined by the broth microdilution method and the effect of combinations was evaluated according to the sum of fractional inhibitory concentration indices (FICIs).
  
  
  RESULTS
  Synergistic activity (FICI  ≤  0.5) was observed for combinations of baicalin with oxytetracycline or tetracycline against 4 of 10 strains tested, whereas the baicalin/oxytetracycline combination possessed the strongest synergistic effect (FICI = 0.418).
  
  
  CONCLUSIONS
  Baicalin acts synergistically with oxytetracycline and tetracycline, enhancing its antimicrobial activity against S. aureus, including methicillin- and tetracycline-resistant strains.
authors.affiliation: Department of Crop Sciences and Agroforestry, Institute of Tropics and Subtropics, Czech University of Life Sciences Prague, Kamycka 129, 16521 Prague 6-Suchdol, Czech Republic.
authors.forename: Pavel
authors.initials: P
authors.lastname: Novy
authors.forename: Jan
authors.initials: J
authors.lastname: Urban
authors.forename: Olga
authors.initials: O
authors.lastname: Leuner
authors.forename: Jaroslav
authors.initials: J
authors.lastname: Vadlejch
authors.forename: Ladislav
authors.initials: L
authors.lastname: Kokoska
mesh_terms: D000900:Anti-Bacterial Agents / Q000494:pharmacology*; D004357:Drug Synergism; D005419:Flavonoids / Q000302:isolation & purification / Q000494:pharmacology*; D006801:Humans; D008826:Microbial Sensitivity Tests; D010118:Oxytetracycline / Q000494:pharmacology*; D031363:Scutellaria / Q000737:chemistry; D013211:Staphylococcus aureus / Q000187:drug effects*; D013752:Tetracycline / Q000494:pharmacology*
chemical_list: D000900:Anti-Bacterial Agents; D005419:Flavonoids; C038044:baicalin; D013752:Tetracycline; D010118:Oxytetracycline