Isolation, characterization and quantitative HPLC-DAD analysis of components of charantin from fruits of Momordica charantia

Abstract

Charantin, a steroidal glycoside, exists as a mixture of stigmasterol glucoside (STG) and β-sitosterol glucoside (BSG) in the fruits of Momordica charantia. Charantin has anti-diabetic activity comparable to insulin. The present work discusses a method for separation of components of charantin namely STG and BSG by simple extraction technique followed by preparative HPLC. The identity of separated components was established by chromatographic as well as spectral techniques. Also reversed phase HPLC-DAD method was developed and validated for estimation of STG and BSG present in fruits of Momordica charantia. The method used C18 column (75 mm × 4.6 mm, 3.5 µm) as stationary phase and methanol: water (98:02, v/v) as mobile phase. Retention times of STG and BSG were found to be 10.707 min and 11.870 min, respectively. The validated method was applied to evaluate content of these components in different extracts and some commercial herbal formulations containing fruits of Momordica charantia.

Keywords: Bitter melon; Charantin; Karela; Momordica charantia; Stigmasterol glucoside; β-Sitosterol glucoside.