title: Separation of triterpenoid saponins from the root of Bupleurum falcatum by counter current chromatography: the relationship between the partition coefficients and solvent system composition.
abstract: A separation method using counter current chromatography coupled with an evaporative light-scattering detection system was developed to purify five triterpenoid saponins from the roots of Bupleurum falcatum. The methanol extract was loaded onto a Diaion® HP20 column and fractionated by a methanol and water gradient elution. The saikosaponin-enriched fraction was obtained by elution with 100% methanol. The two-phase solvent systems used for separation were composed of chloroform/methanol/isopropanol/water at a volume ratio of 60:60:1:60 and 6:6:1:6. The relationship between the isopropanol ratio of each phase and the partition coefficients of the target compounds was investigated by calculating partition coefficient by high-performance liquid chromatography and measuring the accurate composition of each phase by (1) H NMR spectroscopy. Each fraction obtained was collected and dried, which yielded the following five saikosaponins from 700 mg of injected sample: saikosaponin B1 (8.7 mg), saikosaponin A (86 mg), saikosaponin B3 (17 mg), saikosaponin B2 (41 mg), and saikosaponin C (33 mg). Saikosaponin A showed the most potent cytotoxicity against human cancer cells (gastric cancer, AGS cells; breast cancer, MCF-7 cells; and hepatoma, HepG2 cells) after 24 h. The IC50 values for the above three cell types were 34.6, 33.3, and 23.4 μmol/L, respectively.
authors.affiliation: College of Pharmacy, Natural Products Research Institute, Seoul National University, Seoul, Korea.
authors.forename: Kyoung Jin
authors.initials: KJ
authors.lastname: Lee
authors.forename: Mei-Ying
authors.initials: MY
authors.lastname: Xu
authors.forename: Omer
authors.initials: O
authors.lastname: Shehzad
authors.forename: Eun Kyoung
authors.initials: EK
authors.lastname: Seo
authors.forename: Yeong Shik
authors.initials: YS
authors.lastname: Kim
mesh_terms: D000972:Antineoplastic Agents, Phytogenic / Q000737:chemistry / Q000302:isolation & purification* / Q000494:pharmacology; D029972:Bupleurum / Q000737:chemistry*; D049109:Cell Proliferation / Q000187:drug effects; D003377:Countercurrent Distribution / Q000295:instrumentation / Q000379:methods*; D004365:Drugs, Chinese Herbal / Q000737:chemistry / Q000302:isolation & purification* / Q000494:pharmacology; D006801:Humans; D061986:MCF-7 Cells; D018517:Plant Roots / Q000737:chemistry; D014315:Triterpenes / Q000737:chemistry / Q000302:isolation & purification* / Q000494:pharmacology
chemical_list: D000972:Antineoplastic Agents, Phytogenic; D004365:Drugs, Chinese Herbal; D014315:Triterpenes
keywords: Bupleurum falcatum; Counter current chromatography; Saikosaponins; Solvent compositions