Abstract
Abstract: This study presents the first detailed analysis of hydrodistilled essential oils from fresh and air-dried Echinops adenocaulos Boiss. from the flora of Jordan. It aims to investigate the chemical composition and the antioxidant potency of the volatile compounds obtained by conventional hydrodistillation from the fresh and air-dried plant; gas chromatography-mass spectrometry analysis identified 46 and 75 compounds of the obtained essential oils, respectively. The study showed that the major constituent classes in the fresh aerial part are oxygenated diterpenes (76.92%) and oxygenated sesquiterpenes (10.78%), followed by aliphatic compounds (10.12%). However, in the dried aerial part, the main classes are oxygenated diterpene (74.47%) and aliphatic compounds (13.34%). Heyderiol was the most abundant constituent (44.96%), followed by bis(2-ethylhexyl)phthalate (20.12%) and trans-ferruginol (3.14%). Bis(2-ethylhexyl)phthalate (52.51%), followed by heyderiol (21.60%) and (Z)-ternine (8.81%) are the major compounds of the fresh aerial part. The antioxidant activity was tested by DPPH free radical scavenging and ABTS•+ cation radical scavenging. The oils from fresh and dried E. adenocaulos exhibit significant antioxidant activity, with the oil from the dried plant having higher antioxidant activity than that from the fresh one.