Preparative isolation of cyclolanostane-type saponins from Astragalus membranaceus bge. var. mongholicus (Bge.) Hsiao by TLC-MS/MS guided high-speed counter-current chromatography.
Two cyclolanostane-type saponins, astragalosides I and II, were first identified by TLC-MS/MS in the ethyl acetate extract of the roots of Astragalus membranaceus Bge var. mongholicus (Bge.) Hsiao without chemical reference substances. They were then isolated by high-speed counter-current chromatography with a two-step two-phase solvent system of ethyl acetate-2-propanol-water (5:1:5, 50:1:50, v/v/v). The quantities of astragalosides I and II isolated from 1 g of the crude extract were 30.2 mg and 16.5 mg, respectively. Their purities were found to be over 95% by HPLC-ELSD analysis. Their chemical structures were confirmed by 1H and 13C nuclear magnetic resonance analysis.
Han
Quan Bin
QB
Chinese Medicine Laboratory, Hong Kong Jockey Club Institute of Chinese Medicine, Shatin N.T., Hong Kong, P. R. China.
Song
Jing Zheng
JZ
Qiao
Chun Feng
CF
Wong
Lina
L
Xu
Hong Xi
HX
D027885:Astragalus propinquus / Q000737:chemistry*; D002855:Chromatography, Thin Layer; D003377:Countercurrent Distribution; D007810:Lanosterol / Q000031:analogs & derivatives* / Q000302:isolation & purification; D012503:Saponins / Q000302:isolation & purification*; D021241:Spectrometry, Mass, Electrospray Ionization; D053719:Tandem Mass Spectrometry
D012503:Saponins; C497083:lanostanoid; D007810:Lanosterol