Separation and Identification of Swertiamarin from Enicostema axillare Lam.Raynal by Centrifugal Partition Chromatography and Nuclear Magnetic Resonance-Mass Spectrometry*

Separation and Identification of Swertiamarin from Enicostema axillare Lam.Raynal by Centrifugal Partition Chromatography and Nuclear Magnetic Resonance-Mass Spectrometry*

Enicostema axillare, a bitter herb, has been used for the treatment of diabetes in traditional system of medicine in India. Swertiamarin, a bitter and potent hepatoprotective iridoid glucoside (~20 mg) was isolated by Centrifugal Partition Chromatography coupled with Diode Array Detector (DAD) from the crude methanolic extract (1.0 g) of its aerial parts using a biphasic solvent system composed of chloroformmethanol- water (86:74:20, v/v) in ascending mode for the first time. The purity of the compound was found to be >97%. The structure of swertiamarin was determined using spectroscopic data mainly NMR (1H, 13C, DEPT, HSQC and HMBC) and ESI-MS. Compound was also identified by comparing 13C NMR data with those reported and some of the 13C NMR values were revised.