Crystalline isolation and physicochemical characterization of guaiacol as a major constituent of an active spasmolytic fraction of the essential oil of teucrium polium L

ABSTRACT

Following the earlier demonstration of potent spasmolytic effect on Isolated intestinal rabbit preparations by the essential oil of Teucrium polium L., the oil [obtained by steam distillation] was fractionated on thin layer chromatographic plates to 15 fractions. The spasmolytic effect of the fractions were tested on the spontaneous motility of the isolated jejunum of the rabbit. The fraction with R f0.52 was the most potent in this regard, consisting of 20% of the essential oil. Upon subjection of the active fraction to GC analysis, the sesquiterpene alcohol guaiol [constituting 33% of the fraction] and other terpenes were separated. Guaiol, in a crystalline form, was Isolated for the first time from the essential oil of Teucrium polium. The identity of guaiol was confirmed from its physicochemical properties. Guaiol was found to Inhibit the intestinal motility of isolated rabbit jejunum. The extent of inhibition was dose dependent with an ED 50 of 60 Micro M