Phytochemistry of Commiphora mukul
Chemical investigations have focused on the oleogum resin of Commiphora mukul due to its hypolipidemic properties. The oleogum resin contains an essential oil mainly consisting of myrcene, dimyrcene, and polymyrcene. The National Chemical Laboratory (Pune, India) in collaboration with the pharmacology team of the Central Drug Research Institute (Lucknow, India) isolated and chemically characterized the hypolipidemic compounds of the oleogum resin. A stepwise extraction scheme shown in Figure 2 was used to separate the chemical constituents.
Solvent extract, using ethyl acetate, separates the oleogum resin into two parts, gum and resin. The gum is insoluble in ethyl acetate, and it is chemically characterized as a carbohydrate gum (substance belonging to the class of sugars). Because the gum did not possess lipid-lowering activities and proved toxic to experimental animals, it was not studied further. The resinous portion is soluble in ethyl acetate and possesses both anti-inflammatory and lipid-lowering properties. It was further separated into acidic, basic, and neutral fractions that comprised approximately 4%, 0.3%, and 95% of the ethyl acetate-soluble resin, respectively. The basic fraction was devoid of any activity.
Thus, it was discarded. The acidic fraction possessed significant anti-inflammatory activity. The neutral faction possessed lipid-lowering activity. The neutral fraction was further separated into ketonic and non-ketonic fractions to pinpoint the source of the hypolipidemic activity. The ketonic fraction possessed significant lipid-lowering activity, while the non-ketonic fraction showed none. The ketonic fraction is a complex mixture of chemical compounds that belong to the class of steroids as shown below.
GUGGULSTEROLS
STEROL COMPOUNDS
GUGGULSTERONES
Among the compounds listed, Z-Guggulsterone and E-Guggulsterone are responsible for the hypolipidemic activity of the gum resin. In fact, the hypolipidemic activity of Z and E guggulsterones has been determined to be quantitatively comparable to that of the total ethyl acetate extract of the gum resin.
