title: Xanthine oxidase inhibitory properties of Czech medicinal plants.
abstract: OBJECTIVE
  To investigate in vitro xanthine oxidase inhibitory properties of plants traditionally used in Czech Republic and Central-East Europe region for gout, arthritis or rheumatism treatment.
  
  
  METHODS
  Methylene chloride-methanolic and two ethanolic extracts of 27 plant species were screened for in vitro xanthine oxidase inhibitory activity using a spectrophotometric method.
  
  
  RESULTS
  Around 50% of the species exhibited some degree of xanthine oxidase inhibitory properties at 200 μg/mL, showing a moderate correlation (r=0.59) with total phenol content. The most active were methylene chloride-methanolic extracts of Populus nigra and Betula pendula, with IC(50) of 8.3 and 25.9 μg/mL, respectively, followed by 80% ethanolic extract of Caryophyllus aromaticus and Hypericum perforatum, both under 50 μg/mL.
  
  
  CONCLUSIONS
  Populus nigra and Betula pendula were identified as species with the highest xanthine oxidase inhibitory potential in our study. This correlates with the ethnobotanical data on their use in Central European folklore and provides the basis for further investigation on these plants.
authors.affiliation: Department of Microbiology, Nutrition and Dietetics, Czech University of Life Sciences Prague, CZ-165 21 Prague 6, Czech Republic. havlik@af.czu.cz
authors.forename: Jaroslav
authors.initials: J
authors.lastname: Havlik
authors.forename: Raquel
authors.initials: R
authors.lastname: Gonzalez de la Huebra
authors.forename: Katerina
authors.initials: K
authors.lastname: Hejtmankova
authors.forename: Javier
authors.initials: J
authors.lastname: Fernandez
authors.forename: Jitka
authors.initials: J
authors.lastname: Simonova
authors.forename: Martin
authors.initials: M
authors.lastname: Melich
authors.forename: Vojtech
authors.initials: V
authors.lastname: Rada
mesh_terms: D029662:Betula / Q000378:metabolism; D018153:Czech Republic; D004791:Enzyme Inhibitors / Q000494:pharmacology*; D020834:Ethnopharmacology; D005419:Flavonoids / Q000032:analysis / Q000494:pharmacology; D010636:Phenols / Q000032:analysis / Q000494:pharmacology; D010936:Plant Extracts / Q000494:pharmacology*; D010946:Plants, Medicinal; D059808:Polyphenols; D032107:Populus; D014969:Xanthine Oxidase / Q000037:antagonists & inhibitors*
chemical_list: D004791:Enzyme Inhibitors; D005419:Flavonoids; D010636:Phenols; D010936:Plant Extracts; D059808:Polyphenols; D014969:Xanthine Oxidase