Planta Med 2007; 73 - P_204
DOI: 10.1055/s-2007-986985

Chemical constituents from three Inula species. Biological activities

G Panoutsopoulos 1, N Aligiannis 1, IB Chinou 1
  • 1Dept. of Pharmacognosy and Chemistry of Natural Products, School of Pharmacy, University of Athens,-Zografou, 15771, Athens, Greece

The genus Inula consists of variable perennial herbs distributed in Asia, Europe, Africa and predominantly in the Mediterranean region (Asteraceae family, tribe Inuleae). Plants of the genus are used as traditional herbal medicines throughout the world [1]. Inula viscosa (L.) Aiton. (syn. Dittrichia viscosa (L.) Greuter) is a widespread Mediterranean plant proven to be a rich source of sesquiterpenes, lactones and flavonoids. Inula pseudolimonella (Rech. F.) and I. candida subsp. candida are both Greek endemic plants and have never been studied phytochemically before [2]. The non-polar (dichloromethane) and the polar (methanolic) extracts of all species were investigated thoroughly and afforded a new sesquiterpenoid lactone

(1) together with the known inusoniolide and tomentosine. Among the constituents that have been isolated from the three species are the triterpenoids dammara-20,24-dien-3-ol and dammara-20,24-dien-3β-yl-acetate, stigmasterol and α and β-amyrin as well as the monoterpenoid thymol. The polar extracts also yielded the well known oligosaccharide inulin. Their structural elucidation was performed by modern spectral means such as1D-, 2D-NMR and MS and literature data.

All extracts and the isolated compounds were tested for their antimicrobial activity against nine human pathogenic bacteria and fungi by both disc diffusion and dilution methods as well as against two cancer cell lines by MTT assay. Through antimicrobial screening, the extracts proved to be active against several of the human pathogenic bacteria – fungi, while the pure isolated compounds showed a very interesting profile. The new natural compound 1 exhibited a strong cytotoxic activity (IC50 6.0 and 6.9µg/ml respectively).

Acknowledgements: This study has been financially supported by PENED 2001 (70/3/6352)

References: [1] Ceccherelli, P. et al, Phytochemistry, 24, 453 (1985). [2] Ball, P. W. and Tutin, T. G. (1976) „Flora Europaea“, Vol. 4, Cambridge University Press, Cambridge, pp. 133.