Chemical Composition and Antibacterial Activity of the Essential Oil of Zosimia absinthifolia Growing in East Azarbaijan (Iran)

Z. absinthifolia, with local name of "Zarak-e-Kuhi" has been consumed as a spice in some regions of Iran.
In this study, the essential oil obtained from the aerial parts of Zosimia absinthifolia (Apiaceae) (ZaeM) was analyzed by GC-MS. Also, the chemical profile of the oil was compared with the same species collected from different localities. Moreover, the essential oil was investigated for its antimicrobial activity by disc diffusion method.
Analysis of ZaeM by GC-MS resulted nineteen components consisting 98.22% of the total oil. The essential oil was predominantly made up of esters (68.48%) and alcohols (26.04%). The most abundant components of the oil were octyl acetate (47.29%), n-octanol (25.79%), octyl butyrate (10.15%) and octanoic acid octyl ester (7.9%). The relative amounts of the main compounds of Z. absinthifolia essential oils growing in different places were comparable with each other. Both qualitative and quantitative variability of chemical composition of Z. absinthifolia essential oils were possibly related to the individual genotypes or geographical origin. Disc diffusion method was employed for the determination of antimicrobial activity of ZaeM. The results showed that the essential oil just had inhibitory activity against B. subtilis, a gram positive strain. The inhibitory activity could be attributed to the long chain alcohol, octanol (25.79%), which had previously shown antimicrobial activity.
As a conclusion, ZaeM could have antimicrobial potentials on B. subtilis. Further investigations are needed to isolate and identify antimicrobial compounds from this volatile oil.