In vitro activity of methanol extracts of plants used as spices against Mycobacterium tuberculosis and other bacteria

WOS: 000266028800044This study determined the phenolic composition of two thyme species (Lamiaceae), Origanum minutiflorum O. Schwarz and P.H. Davis and Thymbra spicata L. var. spicata, and assessed their antibacterial and antimycobacterial activities. "Kekik" is a collective term used in Turkey for plants that smell like thyme. O. minutiflorum, (locally "Sutculer kekigi", endemic) and T spicata var. spicata (locally "Karakekik") are widely used in Turkey and are important export commodities. The activity of the methanol extracts of these plants is given here for the first time. T. spicata var. spicata exhibited a high level of activity against Mycobacterium tuberculosis (minimum inhibitory concentration MIC 196 mu g/ml), and moderate activity (MIC 640 mu g/ml) against Escherichia coli, Salmonella typhinnurium, Enterobacter aerogenes, and Staphylococcus epidermidis. Carvacrol, rosmarinic acid, hesperidin and naringenin were identified as the major phenolic compounds for T. spicata var. spicata. Carvacrol, rosmarinic acid, eriodictiol and luteolin were identified as the major phenolic compounds for O. minutiflorum. The effective constituents of methanol extracts of these plants are given here for the first time. (C) 2009 Elsevier Ltd. All rights reserved.Scientific and Technological Research Council of Turkey (TUBITAK)Turkiye Bilimsel ve Teknolojik Arastirma Kurumu (TUBITAK); TBAGTurkiye Bilimsel ve Teknolojik Arastirma Kurumu (TUBITAK) [104T336]The authors are grateful to TUBITAK This research was supported by a grant from the Scientific and Technological Research Council of Turkey (TUBITAK), TBAG (Research Grant No. 104T336)

Identification of cytotoxic sesquiterpenes from Laurus nobilis L.

A new sesquiterpene, lauroxepine and six known sesquiterpene lactones, were obtained through bioactivity-directed isolation from a methanol extract of the fruits of Laurus nobilis. The hexane-soluble part of the methanol extract yielded lauroxepine, costunolide and gazaniolide, while the dichloromethane- soluble part of the methanol extract afforded costunolide and four other sesquiterpene lactones including santamarine, reynosin, 11,13-dehydrosantonin and spirafolide. The new sesquiterpene lauroxepine and spirafolide have a rare molecular structure carrying an oxepine ring. Structures of the compounds were determined through 1D and 2D NMR and mass (EI-MS) techniques. The extracts were investigated for both ovarian cytotoxic activity and DNA damaging properties against three yeasts. Among the three tested extracts prepared from flowers, leaves and fruits of L. nobilis, the most cytotoxic active extract against ovarian cancer cell line was found to be the fruit extract with 98% inhibition. Among all tested extracts, only the fruit extract showed marginal inhibition (63.2%) against one DNA repair-deficient yeast strain (pRAD52 Gat). Six known sesquiterpene lactones were found to be highly cytotoxic against the A2780 ovarian cancer cell line, however, lauroxepine was not found to be active in A2780. (c) 2007 Published by Elsevier Ltd