Chemical Composition and Antioxidant Activity of Essential Oils and Hexane Extract of Onopordum arenarium from Tunisia

J Chromatogr Sci. 2020 Apr 23;58(4):287-293. doi: 10.1093/chromsci/bmz113.

Abstract

In the present study, volatile oils from Onopordum arenarium fresh flowers and stems were obtained by hydrodistillation and the non-polar aerial part hexane extract was prepared using a Soxhlet apparatus. The constituents of different organs were identified for the first time by gas chromatography equipped with flame ionization detector and gas chromatography coupled to mass spectrometry. A total of 29 and 25 compounds were identified constituting over 91.6 and 89.2% of the whole constituents from flower and stem volatile oils, respectively. Both organs were constituted mainly of long-chain hydrocarbons (23.3-36.4%) followed by oxygenated long-chain hydrocarbons (31.5-33.8%) and oxygenated monoterpenes (14.4-6.6%). The major identified compound was palmitic acid [25.5% in O. arenarium flower essential oil (EO) and 28.7% in the stem EO]. Eighteen compounds representing 80.7% of the whole constituents were identified in the n-hexane extract, which was characterized by high amounts of triterpenoids (39.6%) and dominated by lupeol acetate (19.2%) and β-amyrin acetate (10.1%). Moreover, all extracts were evaluated for antioxidant potential using 1,1-diphenyl-2-picrylhydrazyl radical assay. The obtained results demonstrated that the EOs and the hexane extract could be a new source of natural potentially bioactive molecules.

MeSH terms

  • Antioxidants / chemistry*
  • Antioxidants / pharmacology*
  • Distillation
  • Flowers / chemistry
  • Gas Chromatography-Mass Spectrometry
  • Hexanes / chemistry
  • Monoterpenes / analysis
  • Oils, Volatile / chemistry*
  • Oils, Volatile / pharmacology*
  • Onopordum / chemistry*
  • Plant Extracts / chemistry
  • Plant Extracts / pharmacology
  • Solvents / chemistry
  • Tunisia

Substances

  • Antioxidants
  • Hexanes
  • Monoterpenes
  • Oils, Volatile
  • Plant Extracts
  • Solvents
  • n-hexane