title: Preparation of Sesquiterpenoids fromTussilago farfaraL. by High-speed Counter-current Chromatography.
abstract: BACKGROUND
  Sesquiterpenoids, such as tussilagone, has effects of raising blood pressure, antiplatelet aggregation, and anti-inflammation activities, which is regarded as index compound for quality control ofTussilago farfaraL.
  
  
  OBJECTIVE
  This study was aimed to obtain an effective method for fast isolation of sesquiterpenoids fromT. farfaraL. by high-speed counter-current chromatography (HSCCC).
  
  
  METHODS
  A solvent optimization method for HSCCC was presented, i.e., the separation factors of compounds after theKvalues of solvent system should be investigated.
  
  
  RESULTS
  A ternary solvent system of n-hexane:methanol:water (5:8:2, v/v/v) was selected and applied for the HSCCC, and 56 mg of tussilagone (2) was isolated fromT. farfaraL., along with two other sesquiterpenoids 5.6 mg of 2,2-dimethyl-6-acetylchromanone (1) and 22 mg of 14-acetoxy-7 β-(3'-ethyl cis-crotonoyloxy)-lα-(2'-methylbutyryloxy)-notonipetranone (3) by HSCCC with high purities. Their chemical structures were elucidated by liquid chromatography-mass spectrometry and nuclear magnetic resonance experiments.
  
  
  CONCLUSIONS
  These results offered an efficient strategy for preparation of potentially health-relevant phytochemicals fromT. farfaraL., which might be used for further chemical research and pharmacological studies by preparative HSCCC.
  
  
  CONCLUSIONS
  The real separation efficiency has been verified by analytical HSCCC.A solvent optimization method for HSCCC was presented and applied to separate and prepare active compounds.A method for rapid and effective separation of target compound Tussilagone with high yield and purity from the flower buds ofTussilago farfara.Two other compounds 2,2-Dimethyl-6-acetylchromanone and 14-acetoxy-7β-(3'-ethyl cis-crotonoyloxy) -lα- (2'-methylbutyryloxy). notonipetranone hasbeen obtained with high purities from flower buds ofTussilago farfara.Abbreviations used:HSCCC: High-Speed Counter-Current Chromatography; LC-MS: Liquid Chromatograph-Mass Spectrometer; NMR: Nuclear Magnetic Resonance; TCM: Traditional Chinese Medicine; HPLC: High Performance Liquid Chromatography; ESI-MS: Electrospray Ionization Mass Spectrometry; PE: petroleum ether.
authors.affiliation: College of Chemistry and Chemical Engineering, Chongqing University, Chongqing, P.R. China; Defense Key Disciplines Lab of Novel Micro-nano Devices and System Techonlogy, Chongqing, P.R. China.
authors.forename: Kun
authors.initials: K
authors.lastname: Cao
authors.affiliation: College of Chemistry and Chemical Engineering, Chongqing University, Chongqing, P.R. China; Defense Key Disciplines Lab of Novel Micro-nano Devices and System Techonlogy, Chongqing, P.R. China; International R and D Center of Micro-nano Systems and New Materials Technology, Chongqing, P.R. China.
authors.forename: Yi
authors.initials: Y
authors.lastname: Xu
authors.affiliation: College of Chemistry and Chemical Engineering, Chongqing University, Chongqing, P.R. China.
authors.forename: Tian-Ming
authors.initials: TM
authors.lastname: Zhao
authors.affiliation: College of Chemistry and Chemical Engineering, Chongqing University, Chongqing, P.R. China; Defense Key Disciplines Lab of Novel Micro-nano Devices and System Techonlogy, Chongqing, P.R. China.
authors.forename: Qing
authors.initials: Q
authors.lastname: Zhang
keywords: High-speed counter-current chromatography; Tussilago farfara L.; preparation; sesquiterpenoids; solvent selection