ANTIBACTERIAL ACTIVITY AND CHEMICAL COMPOSITION OF THE ESSENTIAL OIL FROM FLOWERS OF NERIUM OLEANDER

The objective of this work is to investigate the main chemical composition and antibacterial activity of Nerium oleander flowers growing in Morocco. The chemical composition and antibacterial activity of essential oils obtained from Nerium oleander (family Apocynaceae) were examined. Their chemical composition was determined by hydro-distillation, analysed by GC/MS and GC-FID. To evaluate the antibacterial activities of these aromatic extracts; their in vitro antibacterial activities were determined by disk diffusion testing and minimum inhibitory concentration (MIC). Escherichia coli, Pseudomonas aeruginosa and Staphylococcus aureus were used as test bacterial strains. The analyses for flower part resulted in the identification of 34 compounds, representing 93.21% of the total oil and the yields were 1.76%. The major component was nériine (22.56%), other predominant components were digitoxigénine (11.25%), Amorphane (8.11%), 1.8-cineole (6.58%), α-pinene (5.54%), calarene (5.12%), Limonene (5.01%), β- Phellandrene (4.84%), Terpinene-4-ol (3.98%), sabinene (3.22%), Isoledene (2.94%), 3- Carene (2.56%), Humulene (2.29%), β-Pinene (2.01 %) and Cymen-8-ol (1.67%). The chemical compositions revealed that this study had compositions relatively similar to those of other Nerium oleander essential oils analyzed in other countries. The bacterial strains tested were found to be sensitive to essential oils studied and showed a very effective bactericidal activity with minimum inhibitory concentrations (MIC) ranging from 1.45 to 5.10 mg/mL.