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

This 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 μg/ml), and moderate activity (MIC 640 μg/ml) against Escherichia coli, Salmonella typhimurium, 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.