Antibacterial and Anti Biofilm activity of Eucalyptus Plant Extract Spp

  • Noor A. Al-taai, Nagham M. Al-Gburi, Nuha K. Khalil


The biofilm membrane is one of the basics for the causing of pathological infections of most types of bacteria, so destroying or stopping the formation of this membrane is the first necessary step to control the spread of bacterial diseases.

    The aim of this research is to study the effect of the Eucalyptus plant as an antibacterial and an inhibitor of biofilm formation against a number of bacteria types taken from the zoonosis research unit (Staphylococcus aureus, Escherichia coli, Pseudomonas aeruginosa, Proteuse, Citrobacter, Listeria and Enterococcuse) by using method of minimum inhibitory concentration (MIC), minimum bactericidal concentration (MBC), staining with crystal violet and measuring the optical density (OD) by ELISA , the results revealed that zone of growth inhibition of selected bacteria by Eucalyptus extract was ranged from 20-35 mm at concentration 20 mg/ml, minimum inhibitory concentration (MIC) ranged from (0.6 -20) mg/ml, the extract of Eucalyptus was highly effective against Pseudomonase at 0.6 mg/ml and at 20 mg/ml against Citrobacter, while the minimum bactericidal concentration (MBC) of Eucalyptus was the lowest at 0.3 mg/ml against Pseudomonas and Enterococcus and the highest at 10 mg/ml against Staphylococcus and Proteus and no effect against E. coli and Citrobacter.

    Results of Eucalyptus extract biofilm inhibition by measuring the optical density (OD) were (28.3, 25 %) on Pseudomonas and Staphylococcus aureus at zero time and (26.6, 25 %) after 24 hr from incubation respectively.

    It was concluded from result above that the antibacterial effect of Eucalyptus extract depending on its concentration and it was active in high concentration.

MIC of Eucalyptus against Pseudomonas using tetrazolium as indicator for viable cell at different concentrations starting from 20 mg/ml at left (no bacterial growth) and ending with control at right (shows darken redness color which indicate live bacterial cells) tube 7 considered the MIC.
How to Cite
Noor A. Al-taai, Nagham M. Al-Gburi, Nuha K. Khalil. (2022). Antibacterial and Anti Biofilm activity of Eucalyptus Plant Extract Spp. Revista Electronica De Veterinaria, 139 - 148. Retrieved from