The chemical composition and in vitro antibacterial activities of the oil of Ziziphora clinopodioides Lam. from Iran

The genus Ziziphora is represented in the flora of Iran by four species, Z.capitata L. subsp. capatita, Z.capitata L. subsp. orientalis Samuelsson ex Rech.f., Z.clinopodioides Lam., Z. persica Bunge. and Z.tenuir L. Z.clinopodioides Lam. with the common persian name kakuti-e kuhi comprised nine subspecies native to Iran. In Iranian and Turkish folk medicine, Ziziphora species have been used as sedative, against stomachache and as carminative. In Iranian folk medicine and folklore, the dried aerial parts of this plant have been frequently used as culinary and also in cold and cough treatments.

The composition of the essential oils of Ziziphora clinopodioides Lam. (two samples from two different locations) as well as the in vitro antibacterial activity of their essential oils were studied. The water distilled essential oils from aerial parts of Z. clinopodioides were analyzed by GC and GC/MS. The main compounds of the sample A of Z. clinopodioides were thymol (53.6%), p-cymene (10.5%) and carvacrol (8.7%), while in the sample B, 1,8- cineole (21.6%) and terpinen-4-ol (18.2%), linalool (7.9%) and pulegone (7.7%) were the most abundant constituents. The in vitro antibacterial activity test was carried out using the well diffusion method. Z.clinopodioides oil, sample A, was strongly active against the Gram-pos bacteria: Staphylococcus epidermidis, Staphylococcus aureus and Staphylococcus saprophyticus with MIC value of 0.3, 1.15 and 1.2 (mg/ml) respectively and also against Gram-negative bacteria: Escherichia coli, Shigella flexneri and Salmonella typhi, again with MIC values of 0.3, 0.3, 0.6 (mg/ml) respectively. While, the oil of sample B had moderate inhibitory against the Gram- positive and Gram- negative bacteria comparing to sample A; the inhibitory activity against three Gram- positive, St. aureus, St. epidermidis, St. saprophyticus was shown by the 1.9, 1.2, 1.1 (mg/ml) of MIC value and against Gram- negative bacteria Sh. flexneri, S. typhi and E. coli was shown by 2.2, 1.2 and 1.0 (mg/ml) of the MIC value. Moderate inhibitory activity against Ps. aeruginosa was obtained for both sample A and B.