Chemical Composition, Antioxidant, and Cytotoxic Activity of Essential Oils in the Above-Ground Parts of Sonchus oleraceus L.

Sonchus oleraceus L. is a leafy vegetable that is usually consumed in the area of the Mediterranean and is a frequently used traditional herb to treat a variety of ailments. Previous studies deduced the potent antioxidant and cytotoxic functions of the different extracts and isolated compounds from S. oleraceus . The current study represents the first instance of chemical profiling and bioactivities of the extracted essential oil (EO) of S. oleraceus . The present investigation set out to identify the chemical components of this EO by means of Gas Chromatography with Flame Ionization Detector (GC-FID) and Gas Chromatography-Mass Spectrometry (G004-MS) techniques; assess the oil's antioxidant potencies through 1,1-diphenyl-2-picrylhydrazyl (DPPH) and 2,2'-azinobis-(3-ethylbenzothiazoline-6-sulfonate (ABTS) assays; and evaluate the oil's cytotoxic impact against HepG2 cancer cell lines. The GC-MS chemical profiling revealed the identification of 23 components representing 97.43% of the total oil mass within abundant cyclic ketones (20.15%), nonterpenoidial hydrocarbons (28.77%), and sesquiterpenes (42.19%). The main components were n -nonadecane (28.77%), trans -caryophyllene (23.73%), trans -methyl dihydrojasmonate (19.55%), and cis -cadina-1,4-diene (9.44%). In a dose-dependent manner, this EO demonstrated antioxidant capacities on DPPH and ABTS, with IC 50 values of 609.35 and 804.16 µg/mL, respectively, compared to ascorbic acid. Using doxorubicin as a reference therapy, the MTT assay findings revealed that this oil had remarkable inhibitory effects on the proliferation of HepG2 cancer cell lines, with an IC 50 of 136.02 µg/mL. More studies were recommended for further investigation of new biological roles for this oil and its main components, along with the construction of action mechanisms based on chemical components.