Chemical compositions and antioxidant activity of essential oil of wild and cultivated Dracocephalum kotschyi grown in different ecosystems: A comparative study

Abstract

Dracocephalum kotschyi Boiss. (D. kotachyi), is an aromatic and perennial plant endemic to Iran. This plant is commonly used for the treatment of headache, congestion, stomach and also liver disorders. Furthermore, antihyperlipidemic, immunomodulatory, antinociceptive, cytotoxic and antispasmodic effects have already been reported for D. kotachyi. However, no information is available about environmental factors' impact on the quantity and quality of this plant. The objectives of this study were to compare the biomass, essential oil content, chemical compositions and antioxidant activity of D. kotachyi in three different (natural, agricultural and controlled) ecosystems. In order to do that, the plant samples were selected from each ecosystem in which they consisted of: two natural ecosystems (Nat. 1: altitude of 3040 m and Nat. 2: altitude of 3646 m), two agricultural ecosystems (Agr. 1: altitude of 2539 m and Agr. 2: altitude of 2589 m), and two controlled (Con. 1: altitude of 2393 m and Con. 2: altitude of 2393 m). The results indicated that the maximum aboveground biomass (29.21 g/plant) of D. kotschyi belonged to the sample of the Agr. 2. Also, the samples of Nat. 1 and Con. 1, possessed higher oil essential content as compared with other ecosystems. The highest antioxidant activity of D. kotschyi was obtained in the sample of Con. 1 under the application of broiler litter. According to the findings, Neral (20.29%-28.24%), geranial (17.32%–26.36%), geranyl acetate (7.16%–20.82%) and α-pinene (11%–15.09%) were identified as major chemical compounds of D. kotschyi in all samples except in the Nat. 2. The major chemical compositions in the Nat. 2 ecosystem were trans-carveol (52.65%), limonene (20.13%), geranyl acetate (9.52%) and geranial (4.13%). In general, the cultivation of D. kotschyi treated with broiler litter (Con. 1) leaded to high essential oil content, main chemical compositions and the highest antioxidant activity. Hence, it could be applied as a valuable medicinal plant in various industries and can be considered as an alternative to protect this plant in the natural ecosystems.