title: Simultaneous separation of three isomeric sennosides from senna leaf (Cassia acutifolia) using counter-current chromatography.
abstract: Senna leaf is widely consumed as tea to treat constipation or to aid in weight loss. Sennoside A, A1 , and B are dirheinanthrone glucosides that are abundant and the bioactive constituents in the plant. They are isomers that refer to the (R*R*), (S*S*), and (R*S*) forms of protons on C-10 and C-10' centers and it is difficult to refine them individually due to their structural similarities. The new separation method using counter-current chromatography successfully purified sennoside A, A1 , and B from senna leaf (Cassia acutifolia) while reversed-phase medium-pressure liquid chromatography yielded sennoside A only. n-Butanol/isopropanol/water (5:1:6, v/v/v) was selected as the solvent system for counter-current chromatography operation, and the partition coefficients were carefully determined by adding different concentrations of formic acid. High-resolution mass spectrometry and NMR spectroscopy were performed to verify the chemical properties of the compounds.
authors.affiliation: Natural Products Research Institute, College of Pharmacy, Seoul National University, Gwanak-gu, Seoul, Korea.
authors.forename: Sait Byul
authors.initials: SB
authors.lastname: Park
authors.affiliation: Natural Products Research Institute, College of Pharmacy, Seoul National University, Gwanak-gu, Seoul, Korea.
authors.forename: Yeong Shik
authors.initials: YS
authors.lastname: Kim
mesh_terms: D003377:Countercurrent Distribution; D008968:Molecular Conformation; D018515:Plant Leaves / Q000737:chemistry*; D012676:Senna Extract / Q000737:chemistry* / Q000302:isolation & purification*; D029846:Senna Plant / Q000737:chemistry*; D013237:Stereoisomerism
chemical_list: D012676:Senna Extract
keywords: Counter-current chromatography; Senna; Sennoside A; Sennoside A1; Sennoside B