Chemical composition and antibacterial activity of essential oil of Pelargonium graveolens and its fractions

Abstract

This work aims to study the chemical composition and evaluate the antibacterial activity of Pelargonium graveolens essential oil and its fractions collected in the Er-Rachidia region of Morocco. GC-MS analysis of Pelargonium graveolens essential oil and its fractions yielded majority compounds such as; epi-γ-Eudesmol (16.67 %), Geraniol (12.54 %), β-Citronellol (12, 34 %), Citronellyl formate (7.70 %) and Geranyl tiglate (5.21%), for the crude essential oil of Pelargonium graveolons, while the fractions that is obtained by preparative plate chromatography gave the following compounds, fraction 1 consists mainly of β-Citronellol (35. 83 %) Geraniol (38.78 %), fraction 2 is dominated by epi-γ-Eudesmol (55. 10 %) and α-agorofuran (8.41 %)), as well as fraction 3 is revealed the presence of Geranylgeraniol (23.70 %) and epi-γ-Eudesmol (17.53 %) and Phenylethyl tiglate (12.01 %), fraction 4 consists mainly of Phenylethyl tiglate (58.19 %) and α-agorofuran (8.49 %), then the fraction 5 is represented by the compound majorities such as Geranyl tiglate (30.75 %) and Geranyl butanoate (10.94 %), while the fraction 6 is characterized mainly by 1-Isopropyl-4,7-dimethyl-1 ,2,3,5,6,8a-hexahydronaphthalene (12.08 %). Concerning the antibacterial activity of the essential oil and its fractions 1, 2, 3, and 4 showed bactericidal power against all tested bacteria: Listeria monocytogenes, Escherichia coli, Staphylococcus aureus, and Salmonella typhimurium, also fractions 5 and 6 have bactericidal power against Escherichia coli, Salmonella typhimurium and no power against Staphylococcus aureus and Listeria monocytogenes.