In silico and In vitro Antibacterial Activity of Essential oil of Eucalyptus globulus Labill

Abstract Eucalyptus globulus Labill. Traditionally used as disinfectant, fumigant, insect repellent, it is also used to cure asthma, bronchitis, arthritis, boils etc. The current research is focused on to study the in vitro and in silico antibacterial activity of Eucalyptus globulus essential oil. Essential oil of Eucalyptus globulus was extracted by hydro-distillation method and characterized by GC-MS. In vitro antibacterial activity was done by using agar well diffusion and broth microdillution method. Further the antibacterial activity was predicted in silico by using Autodock vina. Essential oil extraction yield of Eucalyptus globulus leaves was found to be 2.13 ± 0.115%. Total seventeen mono- and sesqui-terpenoids were identified in essential oil, of which eucalyptol (60.327), D-limonene (6.964), terpinyl-acetate (3.564) and gamma gurjunene (2.505%) were the major constituents. Essential oil of Eucalyptus globulus showed significant antibacterial activity against Clinical strains of Escherichia coli, Staphylococcus aureus and Methicillin-resistant Staphylococcus with minimum inhibitory concentration values of 0.125, 0.125 and 0.3125% respectively. In molecular docking study, γ-gurjunine showed good binding energy with penicillin binding protein (3VSL) and MD simulation confirmed the stability of protein ligand complex. Essential oil of Eucalyptus globulus has good antibacterial activity against clinical strains of grams positive and grams negative bacteria. Essential oil of Eucalyptus globulus can be used as antibacterial agent with addition of in vitro and in vivo toxicity.