Chromatographic Analysis (LC-MS and GC-MS), Antioxidant Activity, Total Phenol and Total Flavonoid Determination of Ononis natrix L. Grown in Jordan

The purpose of the present study was to identify, by gas chromatography (GC) and GC-mass spectrometry (GC-MS), the components of the spontaneously emitted volatile organic compounds (VOCs), obtained by Solid-Phase-Micro-Extraction (SPME) and that of the hydrodistilled oil of the fresh flowers and leaves of Ononis natrix, as well as to compare them. The hydrodistilled leaf oil was rich in non-terpenoid aldehydes, whereas its aroma profile contained mainly sesquiterpene hydrocarbons with α-copaene and germacrene D as their major components. The hydrodistilled oil of the fresh flowers, however, revealed nearly equal amounts of terpenoid and non-terpenoid compounds; 51.00% and 46.54%, respectively. The aroma profile of the fresh flowers was dominated by monoterpene hydrocarbons with α-pinene (42.96%) and α-thujene (20.17%) as the predomi¬nant two monoterpenes. Based on the high total phenol and flavonoid contents of the water and ethanol extracts, LC-MS analysis was carried out to identify the major compounds from each sample. From the water extract, eleven compounds were identified, whereas the ethanol extract contained eight, whereby luteolin (from the water extract) and apigenin (from the ethanol one) were named as the major flavonoids, respectively.