title: Separation of four homoisoflavonoids from Caesalpinia sappan by high-speed counter-current chromatography.
abstract: BACKGROUND
  The main chemical constituents of Caesalpinia sappan are homoisoflavonoids. Conventional column chromatographic techniques used for isolation of this type of compounds are tedious, time-consuming and waste solvents. High-speed counter-current chromatography (HSCCC) could be a suitable alternative for the enrichment and purification of these target compounds from traditional Chinese medicine (TCM).
  
  
  OBJECTIVE
  To establish a method to isolate four homoisoflavonoids in one-step separation from C. sappan by HSCCC.
  
  
  METHODS
  The crude extract of C. sappan was fractionated by HSCCC using a two-phase solvent system consisting of chloroform-methanol-water (4:3:2, v/v/v). The separation conditions were: flow rate, 1.0 mL/min; revolution speed, 900 rpm; detection wavelength, 280 nm; separation temperature, 25 °C; sample size, 120 mg crude sample dissolved in a mixture of the upper and lower phases (10 mL each). The retention of the stationary phase was 83%.
  
  
  RESULTS
  Five milligrams of 3'-deoxysappanol, 8 mg of 3-deoxysappanone B, 20 mg of 4-O-methylsappanol and 18 mg of brazilin were obtained in one-step separation from 120 mg of an ethyl acetate extracted fraction of C. sappan. Their purities were 99%, 97%, 90% and 85% by HPLC analysis. The mean recoveries of the four compounds were 83%, 86%, 93% and 85%, respectively.
  
  
  CONCLUSIONS
  The study has shown that HSCCC is effective for the separation and enrichment of the target compounds at a large scale.
authors.affiliation: Shanghai Research Center for Modernization of Traditional Chinese Medicine, Shanghai Institute of Materia Medica, National Engineering Laboratory for TCM Standardization Technology, Chinese Academy of Sciences, Haike Road 501, Zhangjiang High-Tech Park, Shanghai 201203, P.R. China.
authors.forename: Pingping
authors.initials: P
authors.lastname: Xu
authors.forename: Shuhong
authors.initials: S
authors.lastname: Guan
authors.forename: Ruihong
authors.initials: R
authors.lastname: Feng
authors.forename: Renneng
authors.initials: R
authors.lastname: Tang
authors.forename: Dean
authors.initials: D
authors.lastname: Guo
mesh_terms: D001578:Benzopyrans / Q000737:chemistry / Q000302:isolation & purification; D029911:Caesalpinia / Q000737:chemistry*; D002725:Chloroform / Q000737:chemistry; D003377:Countercurrent Distribution / Q000379:methods*; D005419:Flavonoids / Q000737:chemistry / Q000302:isolation & purification*; D007529:Isoflavones / Q000737:chemistry / Q000302:isolation & purification; D000432:Methanol / Q000737:chemistry; D015394:Molecular Structure; D010936:Plant Extracts / Q000737:chemistry / Q000302:isolation & purification*; D015203:Reproducibility of Results; D012997:Solvents / Q000737:chemistry; D014867:Water / Q000737:chemistry
chemical_list: D001578:Benzopyrans; D005419:Flavonoids; D007529:Isoflavones; D010936:Plant Extracts; D012997:Solvents; D014867:Water; D002725:Chloroform; C044362:brazilin; D000432:Methanol