title: Rapid simultaneous determination of major isoflavones of Pueraria lobata and discriminative analysis of its geographical origins by principal component analysis.
abstract: BACKGROUND
  Isoflavones are main bioactive components of Pueraria lobata (Willd.) Ohwi. Puerarin has been used as the marker compound in herb quality evaluation in the Chinese Pharmacopoiea. However, it is also important to include the other isoflavones present in the herb, such as daidzin, daidzein, genistin and genistein, in the evaluation as they also contribute to the overall bioactivity of the herb.
  
  
  OBJECTIVE
  To develop a rapid and reliable method for simultaneous quantitation of isoflavones for P. lobata herb quality evluation.
  
  
  METHODS
  The chromatographic separation was performed on an Agilent rapid resolution liquid chromatographic system through gradient elution. The developed method for the quantification of puerarin, daidzin, daidzein, genistin and genistein was fully validated. When it was applied to analyse the extracts of P. lobata, baseline separation was obtained within 10 min.
  
  
  RESULTS
  The amounts of puerarin, daidzin, daidzein and genistin varied greatly among the samples although their chromatographic fingerprints were similar to each other. The 19 samples studied were classified into three clusters (I-III) by principal component analysis based on the amounts of puerarin, daidzin, daidzein and genistin.
  
  
  CONCLUSIONS
  The classification result can be related to herbal origins, but the classification outcome from the chromatographic fingerprinting similarity approach did not provide any geographical origin information. This shows that bioactive constituents can reflect the intrinsic quality of P. lobata more accurately.
authors.affiliation: Department of Biological Engineering and Environmental Science, Changsha University, Changsha, Hunan, People's Republic of China. cxzh003@163.com
authors.forename: Chenxi
authors.initials: C
authors.lastname: Zhao
authors.forename: Hoi-yan
authors.initials: HY
authors.lastname: Chan
authors.forename: Dalin
authors.initials: D
authors.lastname: Yuan
authors.forename: Yizeng
authors.initials: Y
authors.lastname: Liang
authors.forename: Tsui-yan
authors.initials: TY
authors.lastname: Lau
authors.forename: Foo-Tim
authors.initials: FT
authors.lastname: Chau
mesh_terms: D002853:Chromatography, Liquid / Q000295:instrumentation / Q000379:methods / Q000592:standards; D005843:Geography; D007529:Isoflavones / Q000737:chemistry*; D057230:Limit of Detection; D010936:Plant Extracts / Q000737:chemistry / Q000145:classification; D025341:Principal Component Analysis; D029908:Pueraria / Q000737:chemistry*; D011786:Quality Control
chemical_list: D007529:Isoflavones; D010936:Plant Extracts; C040641:genistin; C013908:daidzin; C004742:daidzein; C033607:puerarin