title: [Determination of cichoric acid in Echinacea purpuea].
abstract: OBJECTIVE
  To analyze the natural change rule of active components of E. purpuea by measuring content of cichoric acid.
  
  
  METHODS
  Reverse HPLC method was used.
  
  
  RESULTS
  The maximum cichoric acid content of the roots occured in seedling age of May, and that of the flowers occured in blooming stage of mid July, but cichoric acid in stems was generally low anyway. The maximum content of cichoric acid in the plant above ground occured in the blooming stage of mid July.
  
  
  CONCLUSIONS
  The measuring method of content of cichoric acid is successful and reliable. The optimum stage of harvest in Echinacea purpuea should be guided by natural change rule of cichoric acid content.
authors.affiliation: School of Pharmaceutical Sciences, Peking University, Beijing 100083, China.
authors.forename: Hong
authors.initials: H
authors.lastname: Wang
authors.forename: Wen-zhi
authors.initials: WZ
authors.lastname: Liu
authors.forename: Xiao-lei
authors.initials: XL
authors.lastname: Lu
authors.forename: Shi-zhong
authors.initials: SZ
authors.lastname: Chen
authors.forename: Tie-min
authors.initials: TM
authors.lastname: Al
mesh_terms: D002109:Caffeic Acids / Q000032:analysis*; D020900:Echinacea / Q000737:chemistry*; D035264:Flowers / Q000737:chemistry; D035261:Plant Components, Aerial / Q000737:chemistry; D018517:Plant Roots / Q000737:chemistry; D010946:Plants, Medicinal / Q000737:chemistry*; D012621:Seasons; D013386:Succinates / Q000032:analysis*
chemical_list: D002109:Caffeic Acids; D013386:Succinates; C100435:chicoric acid