Chloroform extract of underground parts of Ferula heuffelii: secondary metabolites and spasmolytic activity.

Plants from the genus Ferula L. (Apiaceae) were used for various purposes in traditional medicine of different nations throughout the history. Ferula heuffelii Griseb. ex Heuffel is a perennial species endemic for Balkan peninsula. Ten compounds which belong to classes of prenyl-furocoumarin-, prenyl-dihydrofurochromone-, prenyl-benzoyl- and prenyl-benzoylfuranone-type sesquiterpenoids, as well as sesquiterpene coumarins and phenylpropanoids, were, for the first time, isolated from the CHCl3 extract of the underground parts of this plant and identified. Furthermore, extract and three isolated compounds, i.e., latifolone (1), dshamirone (4), and (2S*,3R*)-2-[(3E)-4,8-dimethylnona-3,7-dien-1-yl]-2,3-dihydro-7-hydroxy-2,3-dimethylfuro[3,2-c]coumarin (6) were, for the first time, evaluated for their in vitro antispasmodic activities in three experimental models: spontaneous contraction, and ACh- and KCl-induced contraction of an isolated rat ileum. The extract (0.1-1.3 mg/ml) and compound 6 (1-10 μg/ml) exhibited dose-dependent effect in all three models. Compound 1 (1-6 μg/ml) affected spontaneous contractions and those induced by KCl, while compound 4 (8 μg/ml) displayed only moderate activity with ACh-induced contractions. It can be concluded that tested compounds contribute to exhibited antispasmodic activity of crude extract. Additionally, extract (0.1-1.3 mg/ml) was tested for in vitro relaxant activity on an isolated rat trachea, and relaxed the KCl-induced contractions in a dose-dependent manner.