Chemical Composition, and Antibacterial and Free-Radical-Scavenging Activities of the Essential Oils of a Citronellol Producing New Chemotype of Thymus pubescens Boiss. & Kotschy ex Celak

Abstract

The composition of the essential oils obtained from the flowering aerial parts of two populations of Thymus pubescens, collected from Mishov-Dagh, was determined by the GC-MS analyses. A total of 18 compounds, representing about 95% of the total oils, were identified in both samples of the essential oils. The essential oils of these two populations showed the presence of high amounts of citronellol (42.0% and 42.6%), geranyl acetate (14.0 and 14.0%), geraniol (13.0 and 13.1%), citronellyl acetate (3.9 and 3.8%), L-linalool (7.8% and 7.9%), cis-nerodiol (5.9% and 5.5%) and citronellyl acetate (3.9% and 3.8%). However, in the published literature, carvacrol, thymol and p-cymene were reported to be the major compounds in T. pubescens. This significant difference in the composition of the essential oils was a clear evidence of chemical polymorphism with in the T. pubescens taxon, suggesting that these two populations of T. pubescens were in deed a new chemotype of this species, and the name Thymus pubescens Boiss. & Kotschy ex Celak chemotype Citronellol for this new chemotype has been proposed. The antibacterial and free-radical-scavenging properties of the essential oils of T. pubescens have also been evaluated.