Pharmacognostical studies on Inula fragilis Boiss. & Hausskn.

Inula L. (Asteraceae) species are rich in terpenic compounds, especially sesquiterpene lactones in addition to flavonoids, phenolic acids and they are widely used in folk in our country and in the world. In this study it is planned to carry out phytochemical and biological effect studies on an endemic species Inula fragilis Boiss. & Hausskn. Secondary metabolites were isolated from the aerial parts of the plant extracts prepared with dichloromethane and methanol, respectively. In totally, 13 compounds and six binary mixtures were isolated. The structures of 23 different compounds, including three different triterpenes (11-oxo-urs-12-en-3β-il acetate and α-amyrin:β-amyrin), one steroid binary mixture (stigmasterol:β-sitosterol), eight sesquiterpene lactones (4α,5α-epoxy-10,14H-inuviscolide, confertin:graveolide mix, 4,5-epoxy-10,11,13,14H-inuviscolide:graveolide mix, 1β-hydroxy alantolactone, 4α-hydroxy-9β,10β-epoxy-1,3H-guaia-11(13)-en-12,8α-olide, 11α,13-dihydro-4H-xantholongin-4-O-β-glucoside, 4-hydroxy-1,10H-pseudoguaia-11(13)-en-12,8-olide), eight flavonoid (apigenin, nepetin, luteoline, chrisoeriol:hispiduline, jaseosidin:apigenin, apigenin-7-O-rutinoside, patuletin-7-O-(6''-O-acetyl)glucoside) and 2 phenolic acids (chlorogenic acid and 4-hydroxy benzoic acid) were elucidated by using spectroscopic methods (1D-2D NMR, MS, IR spectroscopy) or by comparison with the standard compound. Methanol, dichloromethane, water extracts and the extracts and fractions used in the isolation studies were subjected to cytotoxicity studies by MTT method on LNCaP, DU-145, PC-3, HeLa, MDA-MB-231, A549 cancer cell lines and PNT1A healthy prostate cell line. The fraction of dichloromethane extract soluble in methanol was found to have the lowest IC50 value in all cancer cell lines. When the cytotoxicity tests of the isolated compounds and binary mixtures were performed on LNCaP and PNT1A cell lines, it was determined that 1β-hydroxy alantolactone was the most remarkable compound with an IC50 value of 6.313±0.467 μM and high cell selectivity in LNCaP cell line.