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Öğe Bioactive constituents from Turkish Pimpinella species(2005) Tabanca N.; Bedir E.; Ferreira D.; Slade D.; Wedge D.E.; Jacob M.R.; Khan S.I.; Kirimer N.; Can Baser K.H.; Khan I.A.A new 'phenylpropanoid', 4-(3-methyloxiran-2-yl)phenyl 2-methylbutanoate (1), a new trinorsesquiterpene, 4-(6-methylbicyclo[4.1.0]hept-2-en-7-yl)butan-2-one (2), and eight known compounds (3-10) were isolated from the essential oils of several Pimpinella species growing in Turkey. The structures of the new compounds were determined by 1D- and 2D-NMR analyses. The absolute configuration of 1 was established via comparison of its optical rotation with that of 'epoxypseudoisoeugenyl 2-methylbutyrate' (11), the absolute configuration of which was determined by chemical degradation and an appropriate Mosher ester formation. Direct bioautography revealed antifungal activity of 1 and 11 against Colletotrichum acutatum, C. fragariae, and C. gloesporioides. Subsequent evaluation of antifungal compounds in a 96-well microtiter assay showed that compounds 1 and 11 produced the most-significant growth inhibition in Phomopsis spp., Colletotrichum spp., and Botrytis cinerea. Compounds 1 and 6 displayed antimicrobial activities against Mycobacterium intracellulare, with IC50 values of 2.78 and 1.29 µM, respectively. © 2005 Verlag Helvetica Chimica Acta AG, Zürich.Öğe Effect of essential oils and isolated compounds from Pimpinella species on NF-?B: A target for antiinflammatory therapy(2007) Tabanca N.; Ma G.; Pasco D.S.; Bedir E.; Kirimer N.; Baser K.H.C.; Khan I.A.; Khan S.I.Pimpinella essential oils and isolated compounds were screened for their inhibitory activity against NF-?B mediated transcription in SW1353 cells. Twelve oils were effective in inhibiting NF-?B mediated transcription. Especially the roots of P. corymbosa, P. tragium and P. rhodanta showed potent activities with IC50 values of 2, 3 and 6 µg/mL, respectively. Five pure compounds, 7 (4-(2-propenyl)phenylangelate), 12 (4-(3-methyloxiranyl) phenyltiglate), 17 (4-methoxy-2-(3-methyloxiranyl)phenyl isobutyrate), 18 (4-methoxy-2-(3-methyloxiranyl)phenylangelate) and 21 (epoxy pseudoisoeugenol-2-methylbutyrate) inhibited NF-?B mediated transcription with IC50 values of 5.5, 1.2, 0.01, 3.6 and 11 µg/mL, respectively. None of the compounds were cytotoxic to mammalian cells. These findings add significant information to the pharmacological activity of Pimpinella species and their beneficial effects and use in disease prevention especially those related to inflammation. Copyright © 2007 John Wiley & Sons, Ltd.Öğe Estrogenic activity of isolated compounds and essential oils of Pimpinella species from Turkey, evaluated using a recombinant yeast screen(2004) Tabanca N.; Khan S.I.; Bedir E.; Annavarapu S.; Willett K.; Khan I.A.; Kirimer N.; Baser K.H.C.Several plants and plant-derived pure compounds, designated as phytoestrogens, have been reported to cause estrogenic effects. They have been used for alleviation of menopausal symptoms, prevention of osteoporosis, heart disease and cancer. There is an increased interest in studying phytoestrogens such as isoflavones and lignans for their use as replacements for synthetic estrogens. In this study, the estrogenic activity of essential oils of eleven Pimpinella species and the compounds isolated from these species were evaluated using the yeast estrogen screen (YES) assay. The essential oils containing (E)-anethole as major compound showed estrogenic activity in the YES assay, except for the aerial parts without fruits of P. anisetum and P. flabellifolia. The percent maximal response produced by most anethole-containing oils was 30-50%. Fruits of P. isaurica and P. peucedanifolia were estrogenic in spite of the absence or trace amount of anethole, respectively. This study indicates that the estrogenic activity of Pimpinella oils is not solely due to the presence of anethole. Components other than anethole may be responsible for contributing towards the estrogenic activity. The essential oils from different species varied in their estrogenic potencies (relative potency from 8.3 × 10 -8 to 1.2 × 10-6 compared to 17ß-estradiol) and among the different plant parts, the fruit oils of most species were estrogenic followed by the aerial parts without fruits and the root oils and their EC 50 values varied from 45 µg/mL to 650 µg/mL.Öğe Patterns of essential oil relationships in Pimpinella (Umbelliferae) based on phylogenetic relationships using nuclear and chloroplast sequences(2005) Tabanca N.; Douglas A.W.; Bedir E.; Dayan F.E.; Kirimer N.; Baser K.H.C.; Aytac Z.; Khan I.A.; Scheffler B.E.Hydro-distilled essential oils from fruits, aerial parts (without fruits) and roots of Pimpinella species native to Turkey and their phylogenetic relationships to one another were examined. Phytochemical investigation of the essential oils of 19 species resulted in isolation of 16 phenylpropanoids, four sesquiterpenes and two azulene-type norsesquiterpenes. The structures of the isolated compounds were determined primarily from 1D- and 2D-NMR experiments as well as liquid chromatography-mass spectrometry and gas chromatography-mass spectrometry. Phylogenetic relationships among 26 species were evaluated using ITS 1, ITS 4 nuclear rDNA and psbA-trnH cpDNA sequences. In this study, significance and occurrence of phenylpropanoids, azulenes and geijerenes are discussed from a phylogenetic, chemical and biosynthetic perspective. The distribution of different classes of compounds and their putative associations with one another as per current knowledge of their biosynthetic pathways indicates that this information, in conjunction with the phylogeny, could provide valuable information regarding the presence and perhaps evolution of the different classes of compounds. Analysis of the phenylpropanoid components indicates that (E)-anethole is an obligatory intermediate of this pathway. The various Pimpinella species differ primarily in their ability to acylate anethole, suggesting that while the pathway leading to anethole is common to this genus, species differ in their enzymatic machinery leading to acylate. The relationship between azulenes and geijerenes is not as intuitive, but all Pimpinella species analysed in this study have the biochemical machinery required to synthesize these chemical classes. © NIAB 2005.
