title: [Molecular identification of astragali radix and its adulterants by ITS sequences].
abstract: OBJECTIVE
  To explore a new method for identification Astragali Radix from its adulterants by using ITS sequence.
  
  
  METHODS
  Thirteen samples of the different Astragali Radix materials and 6 samples of the adulterants of the roots of Hedysarum polybotrys, Medicago sativa and Althaea rosea were collected. ITS sequence was amplified by PCR and sequenced unidirectionally. The interspecific K-2-P distances of Astragali Radix and its adulterants were calculated, and NJ tree and UPGMA tree were constructed by MEGA 4.
  
  
  RESULTS
  ITS sequences were obtained from 19 samples respectively, there were Astragali Radix 646-650 bp, H. polybotrys 664 bp, Medicago sativa 659 bp, Althaea rosea 728 bp, which were registered in the GenBank. Phylogeny trees reconstruction using NJ and UPGMA analysis based on ITS nucleotide sequences can effectively distinguish Astragali Radix from adulterants.
  
  
  CONCLUSIONS
  ITS sequence can be used to identify Astragali Radix from its adulterants successfully and is an efficient molecular marker for authentication of Astragali Radix and its adulterants.
authors.affiliation: Institute of Chinese Materia Medica, China Academy of Chinese Medical Science, Beijing 100700, China.
authors.forename: Zhan-Hu
authors.initials: ZH
authors.lastname: Cui
authors.forename: Yue
authors.initials: Y
authors.lastname: Li
authors.forename: Qing-Jun
authors.initials: QJ
authors.lastname: Yuan
authors.forename: Li-She
authors.initials: LS
authors.lastname: Zhou
authors.forename: Min-Hui
authors.initials: MH
authors.lastname: Li
mesh_terms: D031583:Althaea / Q000145:classification / Q000235:genetics; D027885:Astragalus propinquus / Q000145:classification / Q000235:genetics*; D018744:DNA, Plant / Q000737:chemistry / Q000235:genetics*; D004275:DNA, Ribosomal / Q000737:chemistry / Q000235:genetics*; D021903:DNA, Ribosomal Spacer / Q000235:genetics; D007887:Fabaceae / Q000145:classification / Q000235:genetics; D000455:Medicago sativa / Q000145:classification / Q000235:genetics; D008969:Molecular Sequence Data; D010802:Phylogeny; D018517:Plant Roots / Q000235:genetics*; D012335:RNA, Ribosomal / Q000235:genetics; D012340:RNA, Ribosomal, 5.8S / Q000235:genetics; D017422:Sequence Analysis, DNA; D013045:Species Specificity
chemical_list: D018744:DNA, Plant; D004275:DNA, Ribosomal; D021903:DNA, Ribosomal Spacer; D012335:RNA, Ribosomal; D012340:RNA, Ribosomal, 5.8S; C065096:RNA, ribosomal, 26S