The Essential oil of Eucalyptus alba L. Growing on the Salt Zone of Fatick (Senegal) as a Source of 1,8Cineole and Their Antibacterial Activity

Members of the genus Eucalyptus are potential sources of number of commercial essential oils and aromachemicals. In present study, the essential oils isolated by hydrodistillation from the leaves of Eucalyptus alba were analyzed by GC-FID and GC-MS. Essential oil yields ranged from 2.41 to 4.35%. In total 18 constituents were identified, accounting for 99.0 to 99.7% of the total compositions. 1,8-cineole was present in all samples as the major component (76.5-88.1%). In addition to this compound, others that were found including limonene (3.8–8.6%), α-terpineol (1.4–2.8%), globulol (1.3–6.3%) and α-pinene (1.5–1.8%). The essential oil showed a strong antibacterial activity against S. aureus ATCC 29213 which is translated by an MIC of 1.25 mg/mL and good activity against E. coli ATCC 25922 (6.25 mg/mL) and E. faecalis ATCC 29212 (6.25 mg/mL). To our knowledge, our study is the first report of E. alba essential oils characterized by a high 1,8-cineole content (>76.5%). They may have potential applications in food and pharmaceutical products. Keywords: Eucalyptus alba, essential oils, antibacterial activity, 1,8-cineole and GC-SM