Phytochemical Profile of Inula britannica from Bulgaria.

The flower heads of Inula britannica L. of Bulgarian origin afforded sesquiterpene lactones (gaillardin, britannin, I1, 13-dihydroinuchinenolide B, ivalin, pulchellin C), triterpenoids (3-0-palmitates of 160-hydroxylupeol, 16β-hydroxy-β-amyrin, and faradiol) and flavonoids (quercetin, luteolin, luteolin-7-0- glucoside). All compounds are known and they were identified by spectral methods. The observed differences in the chemical content of the chloroform and methanol extracts were also reflected in their free radical scavenging activity, evaluated by DPPH and ABTS assays. Intraspecific variability of L britannica is discussed.