title: Chemical constituents and antibacterial property of the essential oil of the roots of Cyathocline purpurea.
abstract: BACKGROUND
  Cyathocline purpurea (D. Don.) O. Ktze. (Asteraceae) is a rare existence Indian medicinal plant and traditionally has antimicrobial property.
  
  
  OBJECTIVE
  The aim of the present study was to identify chemical composition of the essential oil from the roots of Cyathocline purpurea and to screened in vitro antibacterial activity against eight human pathogenic bacteria.
  
  
  METHODS
  The essential oil of roots was analyzed by using GC-FID and GC-MS. The antibacterial activity of oil was tested against four Gram-positive and four Gram-negative bacteria and antibacterial activity was determined by the tube dilution method.
  
  
  RESULTS
  The main constituents of the oil were thymohydroquinone dimethyl ether (57.4%) and β-selinene (14.0%), among twenty five identified compounds, which represented 90.1% of the total oil. The oil was found active against Gram-positive bacteria with minimal bactericidal concentration (MBC) values in the range of 0.26-0.57 mg/mL.
  
  
  CONCLUSIONS
  This is the first report on the chemical composition and antibacterial activity of the essential oil of roots of Cyathocline purpurea. The observation of MBC assay suggested that the Gram positive microorganisms were susceptible to essential oil, while oil was found to be resistant against Gram-negative bacteria, and the oil has bactericidal property.
authors.affiliation: Department of Phytochemistry, Regional Medical Research Centre, Indian Council of Medical Research, Belgaum, Karnataka 590010, India. joshirk_natprod@yahoo.com
authors.forename: Rajesh K
authors.initials: RK
authors.lastname: Joshi
mesh_terms: D000900:Anti-Bacterial Agents / Q000737:chemistry / Q000494:pharmacology*; D019659:Asteraceae; D001419:Bacteria / Q000187:drug effects*; D024881:Drug Resistance, Bacterial; D008826:Microbial Sensitivity Tests; D009822:Oils, Volatile / Q000737:chemistry / Q000494:pharmacology*; D018517:Plant Roots
chemical_list: D000900:Anti-Bacterial Agents; D009822:Oils, Volatile