Preparation of Sesquiterpenoids from Tussilago farfara L. by High-speed Counter-current Chromatography

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 of Tussilago farfara L. OBJECTIVE: This study was aimed to obtain an effective method for fast isolation of sesquiterpenoids from T. farfara L. by high-speed counter-current chromatography (HSCCC). MATERIALS AND METHODS: A solvent optimization method for HSCCC was presented, i.e., the separation factors of compounds after the K values 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 from T. farfara L., 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. CONCLUSION: These results offered an efficient strategy for preparation of potentially health-relevant phytochemicals from T. farfara L., which might be used for further chemical research and pharmacological studies by preparative HSCCC. SUMMARY: 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 of Tussilago 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 of Tussilago 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