title: The study on the extraction method of indirubin from Indigo Naturalis.
abstract: OBJECTIVE
  To discuss how to extract the indirubin of the higher purity from Indigo Naturalis.
  
  
  METHODS
  After extracting the indirubin from Indigo Naturalis by acetic ether, compare the separation effect of the extract in Si gel column with that in alumina column.
  
  
  RESULTS
  The indirubin in Indigo Naturalis by Si gel column chromatography is chosen. The purity of indirubin is 98.3% after Si gel column chromatography.
  
  
  CONCLUSIONS
  The indiruhbin of the higher purity was attained by the simple experimental method.
authors.affiliation: Guangdong Pharmaceutical College, Guangzhou 510224, China. lhc822@163.com
authors.forename: Li-hui
authors.initials: LH
authors.lastname: Cheng
mesh_terms: D002851:Chromatography, High Pressure Liquid / Q000379:methods; D004365:Drugs, Chinese Herbal / Q000737:chemistry / Q000302:isolation & purification; D007211:Indoles / Q000032:analysis / Q000302:isolation & purification; D031219:Isatis / Q000737:chemistry*; D018515:Plant Leaves / Q000737:chemistry; D018547:Plant Stems / Q000737:chemistry; D010946:Plants, Medicinal / Q000737:chemistry*; D011786:Quality Control; D015203:Reproducibility of Results; D013678:Technology, Pharmaceutical / Q000379:methods*
chemical_list: D004365:Drugs, Chinese Herbal; D007211:Indoles; C027185:indirubin