İlaç Hammaddesi Kaynağı Bazı Scutellaria L. Türleri Üzerinde Farmakognozik Araştırmalar

Abstract

Genus Scutellaria (Lamiaceae), which includes about 350 species in worldwide, is widespread in Europe, America and East Asia. It is represented by 16 species in the flora of Turkey. Scutellaria species are the most popular herbs in traditional Chinese medicines and are used in the treatment of gastrointestinal disorders such as diarrhea, cramps, nausea, vomiting; inflammation, hypertension, cardiovascular diseases, bacterial and viral infections, and for anticancer purposes. In the present study, three endemic Scutellaria species (S. salviifolia Benth., S. glaphyrostachys Rech.f. and S. rubicunda Stapf. subsp. brevibracteata) were studied for their chemical compositions by isolation and LC-MS/MS studies; some biological effects were determined according to the effects and uses of the species. As a result of the phytochemical studies, the structures of 22 compounds, 4 of which are new, were elucidated by advanced spectroscopic methods. The new compounds are two -pyrone glucosides, 3,4-dihydroxy-6-methylpyran-2-one 3-O-β-glucopyranoside (=scusalvioside A) and 3,4-dihydroxy-6-methylpyran-2-one 3-O-β-(6'-O-E-caffeoyl)glucopyranoside (=scusalvioside B) with new skeletal structure and two iridoid glucosides, 6'-O-E-caffeoyl 8-epi-loganic acid and 6'-O-E-caffeoyl geniposidic acid. Biological effects of extracts, fractions and pure compounds from active fractions were investigated by DPPH, NO, SO and ABTS radical scavenging capacities, cytotoxic activities against HEp-2 and HeLa cancer cells and healthy cells of RAW 264.7 and L929; antiinflammatory effects via NO, IL-6 cytokine levels in LPS-stimulated RAW 264.7 cells. The results showed that they possessed higher DPPH radical scavenging capacity than other radicals, selective cytotoxicity against cancer cells, and significant antiinflammatory effect on the cytokine levels. Our thesis work, with detailed phytochemical and biological studies on 3 endemic Scutellaria species growing in our country, is important in terms of finding new species that can be suggested instead of Scutellaria species used in the treatment and obtaining new drug candidate molecules.