Chemometric study of the effects of the geographical origin and the collection period on the chemical compositions and the antimicrobial activities of Pituranthos tortuosus essential oils.

Abstract

The present study aims to analyze the chemometric variation of the chemical composition of the aerial part's essential oils of Pituranthos tortuosus, collected from different regions from Tunisia (Majoura and Sened (Gafsa), Sbeitla (Kasserine), and Eljem (Mahdia)) during the period from February to June and to assess their antimicrobial activity. The different samples of the aerial parts of P. tortuosus were hydrodistillated during 4 h. The obtained essential oils were analyzed by GC/FID and GC/MS techniques. The antimicrobial activity of these essential oils samples was evaluated in vitro using Petri dishes against Staphylococcus aureus subsp. aureus, Pseudomonas aeruginosa, Escherichia coli, and Candida albicans. The obtained results showed that the yields of all essential oils were ranging from 0.42 to 0.77 %. They differ significantly (p ≤ 0.01) with the regions of collection. The chromatographic analysis of these essential oils displayed different chemical compositions leading to the identification of eight chemotypes. The majority of their chemical compounds differ significantly with the collection regions (p ≤ 0.05). The studied antimicrobial effects of the essential oils revealed significant differences (p ≤ 0.02) with the collection region. All the essential oils displayed an important antimicrobial effect against S. aureus and C. albicans.