Chemical Composition and antimicrobial activity of essential oils of two wild olive subspecies Olea europaea subsp. europaea var. Sylvestris and the endemic Olive Olea europaea subsp.lapperinie from Algeria

Abstract

Leaves of the Olea europaea L. species are frequently utilized in both folk and modern medicine.In nowadays are strongly valuable for their beneficial effects to treat a multitude of bacterial and inflammation-type diseases, two wild olive subspecies fixed in this research: the widespread Mediterranean Olea europaea subsp. europaea var. sylvestris and the endemic Olea europaea subsp. laperrinei from Saharan region, Despite its ecological value, the chemical composition of subsp. laperrinei oil remains unknown, the samples were harvested from the different geographical area. Gas Chromatography-Mass Spectrometry(GC-MS) and Gas Chromatography-flame-ionization detection (GC-FID) analysis of subsp europaea var. sylvestris allowed the identification of 29 compounds oil with Nonanal (11.82%), Theaspiranea A (9.81%), 3-hexen-1-ol,benzoate(9.31%), β-damascenone (6.87%), α-pinene (6.32%), Farnesol (6.10%) as a major constituents, while the subspecies of the Saharan region were resultedthe identification of 31 compounds where α-pinene (16%), β-Ocimene (12.82%), dl-Limonene(8.20%), Nonanal (8.18%), was the main components .The Monoterpene hydrocarbons represented the most abundant class in the two essential oils samples. The results of the disc diffusion method showed that the two volatile oils have efficient antibacterial activity but, subsp. laperrinei essential oil has a higher range of inhibition, in which P. aeruginosa and B. subtilis showed extreme sensitivity, while the K. pneumoniae bacterium shows great resistance to the two essential oils. These results demonstrated the medicinal value of olive leaves, as well as the impact of climate on the volatiles produced.