Extraction conditions, chemical composition and biological activity of essential oil of Allium schoenoprasum L. bulb from Quang Tri province, Vietnam

Abstract

This paper presents a comprehensive investigation on the extraction of essential oil from Allium schoenoprasum L. (AS) bulbs collected in Quang Tri province, Vietnam. Effects of extracting conditions on the quantity of extracted essential oil were investigated, followed by the evaluation of physicochemical characteristics, chemical composition and biological activities. The hydro-distillation process under suitable extracting conditions (extraction time of 3 h, NaCl concentration of 5 %, material-to-NaCl solution ratio of 1:2) allowed obtaining the highest essential oil yield of 0.290 ± 0.003 %. Chemical composition analysis (Quadrupole GC/MS) of the AS bulb essential oil in xylene indicated that disulfide and trisulfide compounds, as major components, accounted for 97.53 % of the identified compounds. The obtained AS bulb essential oil exhibited high antioxidant activity, which is significantly higher than that of ascorbic acid, in the 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical test. Moreover, it provided strong antibacterial activity against Escherichia coli, methicillin−resistant Staphylococcus aureus, methicillin sensitive Staphylococcus aureus and moderate inhibition activity against carbapenem-resistant Pseudomonas aeruginosa and Streptococcus pneumoniae.

Keywords

• Allium schoenoprasum L.
• Bulb
• Essential oil
• Antioxidant activity
• Antibacterial activity
• Hydrodistillation