Chemical Composition and Anti–Helicobacter pyloriActivity of the Essential Oil ofPistacia vera

Abstract
The chemical composition of the essential oil obtained by hydrodistillation of Pistacia vera L. gum was analyzed using Gas Chromatography-Mass Spectrometry (GC-MS). Twenty compounds were identified, representing 99.5% of the total components. α-Pinene, β-pinene, and α-thujene were found to be the major constituents. The bacteriostatic activity of the essential oil against 12 clinical isolates of Helicobacter pylori was determined using the hole-plate method. All isolates were sensitive to the essential oil, and the Minimum Inhibition Concentration (MIC) was 1.55 mg/ml for all isolates using the agar dilution method.