Antibacterial Activity of Essential oils Isolated from Eucalyptus globulus Labill and Eugnia caryophyllata Thunbery (Family Myrtaceae): A comparative study

The essential oils of Eucalyptus globulus Labill and Eugnia caryophyllata Thunbery analyzed by Thin Layer Chromatography TLC. The results showed that TLC plates separated five compounds from E. globulus oils and four compounds from E. caryophyllata oils with different Rf values. The obtained essential oils from leaves E. globulus and flower buds E. caryophyllata were tested on Escherichia coli and Staphylococcus aureus, by using agar well diffusion method, to determine its antibacterial activities. The strongest effected was noted in E. globulus oils against S. aureus and E.coli with diameter of zone of inhibition (25 mm and 23 mm respectively). While the E. caryophllata oils showed the least effect on S. aureus and E. coli in compare with E. globulus oils with diameter of zone of inhibition (20 mm and 18 mm respectively). We concluded that the essential oils obtained from the leaves of E. globulus offer significant antibacterial activity toward E.coli and S. aureus