An improved HPLC method for simultaneous estimation of isocurcumenol, ar-turmerone and α,β-turmerone in hexane soluble fraction of Curcuma longa and its formulations

Abstract

Curcuma longa (C. longa), a perennial herb, is a member of the Zingiberaceae (ginger) family and possesses a wide array of biological activity. Standardized hexane soluble extract of C. longa rhizomes [Herbal Medicament (HM)] had shown very good anti-stroke activity. A validated High Performance Liquid Chromatography (HPLC) analysis method for isocurcumenol, ar-turmerone and α,β-turmerone was developed for estimation of these compounds in different batches of HM oil and capsules. An alternate equation has been developed for the quantification of α,β-turmerone (an unstable major constituent of HM) using calibration curve of ar-turmerone. This method was applied successfully in stability testing, forced degradation studies of ar-turmerone in pure form, bulk HM oil and HM capsule formulation. The results indicated that ar-turmerone was found to be susceptible for oxidative, photolytic and heat conditions.