Effective separation and analysis of E- and Z-guggulsterones in Commiphora mukul resin, guggulipid and their pharmaceutical product by high performance thin-layer chromatography-densitometric method

A high performance thin-layer chromatographic (HPTLC) method for the simultaneous determination of the hypolipidemic agents, E- and Z-isomers of guggulsterone in Commiphora mukul resin, guggulipid (ethyl acetate extract of resin), and its pharmaceutical formulation, was developed. The developed system was efficient enough to separate both isomers from their conger, 17,20-dihydroguggulsterone (3). HPTLC glass plates, pre-coated with silica gel 60F-254, were used as a stationary phase. The mobile phase consisted of toluene:acetone (9.3:0.7, v/v) which gave well resolved spots for E- and Z-guggulsterones (R-f: 0.52 +/- 0.01, and 0.67 +/- 0.01, respectively) following double development of chromatoplate with the same mobile phase under unsaturated conditions. The analyte stability towards the developed chromatographic procedure was also investigated by two-dimensional (2D) HPTLC analysis. 17,20-Dihydroguggulsterone (3) was identified by the electrospray ionization quadrupole time-of-flight tandem mass spectrometry (ESI-QTOF-MS/MS) analysis. (C) 2011 Elsevier B.V. All rights reserved.