Relation between the antimicrobial activity and the chemical composition of the essential oil of Sidevitis sipylea boiss. (labiatae)

The antimicrobial activity of the essential oil of Sideritis sipylea Boiss. (Labiatae) was studied. The essential oil was separated into five fractions by preparative TLC and the antimicrobial activity of each fraction was tested. The results showed that the different fractions varied in their antimicrobial activity. The fractions with the highest activity were analysed by GC‐MS analysis and it was shown that the main constituents responsible for the antimicrobial activity were alcohols.