CHEMICAL VARIABILITY AND ANTIMICROBIAL ACTIVITY OF AJUGA LAXMANNII (L.) BENTH. (LAMIACEAE) ESSENTIAL OIL

Ajuga plants have had a long history of ethnopharmacological use worldwide. Based on the papers published so far, it seems that there has been a great interest in isolation, structural elucidation and testing of non-volatile Ajuga phytochemicals. The composition of hydrodistilled aerial part volatiles obtained from six populations of wild-growing A. laxmannii was investigated by means of GC and GC-MS analysis. The oils were screened for in vitro antibacterial and antifungal activity against a panel of laboratory control strains using the broth microdilution assay. The analyses resulted in the identification of one hundred fourteen constituents, accounting for 79.6-97.3% of the total composition of the oils. The main components of the analyzed samples were (E)-phytol (5.3-26.1%), nonacosane (2.3-25.6%), coumarin (tr-22.7%), 1-octen-3-ol (0-21.2%), (Z)-3-hexen-l-ol (0-20.5%), linalool (0-13.7%) and heptacosane (0.6-10.5%), which all together contributing more than two thirds to the compounds detected. Among the microorganisms tested the most susceptible strain was Pseudomonas aeruginosa (minimal inhibitory/bactericidal concentration = 1.25/2.5 mg mL-1). Acta Medica Medianae 2017;56(2):92-101.