Simultaneous determination of E- and Z-guggulsterones in dietary supplements containing Commiphora mukul extract (guggulipid) by liquid chromatography

Guggulipid, the standardized product from the extraction of the ole-gum-res in from the Commiphora mukul plant, has been marketed as a hypolipidemic ag ent. The ketosteroids, cis and trans-4,17(20)-pregnadiene-3,16-dione, known as E- and Z-guggulsterones, respectively, are the main ingredients in gugg ulipid. A liquid chromatographic method was developed for simultaneous dete rmination of E- and Z-guggulsterones in guggulipid preparations using synth etic E- and Z-guggulsterone standards. Realtively low amounts of guggulster ones (E and Z) were found in commercial guggulipid preparations in comparis on with the manufacturer's claim of 2.5%. The mixture of E- and Z-guggulste rones was extracted and separated on a Symmetry Cls reversed-phase column, with a mobile phase of acetonitrile-water (46 + 54, v/v) and detected at 24 2 nm, The retention times of E- and Z-guggulsterones are approximately 8 an d 11 min, respectively. Assay quantitation was based on the calibration cur ve obtained from a mixture of synthetic standard E- and Z-guggulsterones. E xperimental data on selectivity, linearity, accuracy, and recoveries are pr esented.