Phytochemical Evaluation and Antioxidant Activity of Essential Oil, and Aqueous and Organic Extracts of Artemisia dracunculus

Background The genus Artemisia has various medicinal effects. Artemisia dracunculus (tarragon) is one of the species that belongs to the genus Artemisia, cultivated in Iran. Objectives The current study aimed to evaluate the antioxidant activity of extracts and essential oil obtained from aerial parts of A. dracunculus. Methods The total amounts of phenolics, flavonoids and proanthocyanidins as well as the antioxidant activity in the various extracts (methanol, dichlormethane, water, n-hexane, ethyl acetate and n-butanol extracts) of A. dracunculus were assessed by four different antioxidant activity tests (DPPH (2, 2’-diphenyl 1-picrylhydrazyl) free radical scavenging, reducing power, ferrous chelating activity and trolox equivalent antioxidant capacity (TEAC) assay). Vitamin C, butylated hydroxytoluene (BHT), ethylenediaminetetraacetic acid (EDTA) and quercetin were used as reference compounds. Gas chromatography (GC) and gas chromatography-mass-spectrometry (GC-MS) were used to identify the compositions of the essential oil. Thiobarbituric acid reactive species (TBARS) and β-carotene bleaching (BCB) methods were used to evaluate the antioxidant activity of the essential oil. Results The methanol extract showed the highest antioxidant activity among others in all methods. Estragole (57.1%) was the major component of the essential oil of the plant. The essential oil showed a weak activity in BCB test. Conclusions The methanol extract showed the highest activity in all tests and was a rich source of antioxidants, with high level of polyphenolic content.