Investigation of Components of Seven Species of Thyme Essential Oils and Comparison of their Antioxidant Properties

Thyme is one of the mint family geniuses that belongs to Nepetoideae subfamily. This plant has been known as an antiseptic, antispasmodic and antitussive. Thyme essential oil has many properties that one of which is antioxidant activity.
The aim of this study was the investigation of seven thyme oils and the comparison of their antioxidant activities. In this paper, seven species of thyme essential oils from different regions have been collected and dried.
The essential oil was extracted by using a Clevenger-type apparatus as British pharmacopoeia for four hours. Obtained essential oils were analyzed by gas chromatography–mass spectroscopy (GC/MS) technique.
Different compounds were identified in the essential oils with different percentages. The main compound in Thymus daenensis and Thymus vulgaris was thymol with percentage of 43.8 for the former and 45.1 for the latter. The dominate compounds in Thymus migricus, Thymus eriocalyx, Thymus serpylum, Zataria multiflora and Thymus kotschyanus were linalool (41.8%), geraniol (61.8%), para cymene (23.8%), carvacrol (57.7%), and Pulegone (37.2%), respectively. Antioxidant activity of essential oils was measured by 2,2-diphenyl-1-picrylhydrazyl )DPPH) radical scavenging test.
Antioxidant activities of Thymus vulgaris, Thymus daenensis, and Zataria multiflora were higher than the other essential oils.