The chemical compositions of the essential oils obtained from the aerial parts of five taxa of Sideritiswere analyzed using various GC−MS techniques. A total of 99 different compounds was identified,and significant differences (qualitative and quantitative) were observed between the samples. Thein vitro antimicrobial activity of the essential oils against six bacteria and three fungi is also reported. Keywords: Sideritis essential oils; antimicrobial activity; GC−MS
