Antibacterial Effect of Myrtus Communis Hydro-Alcoholic Extract on Pathogenic Bacteria

Background: Today, due to the changes in the form of the resistance of pathogenic
bacteria, discovering new antimicrobial drugs is under study. So, the aim of this study is to
evaluate the antimicrobial properties of the extract of the myrtle herb on some of
pathogenic bacteria.
Materials and Methods: Hydroalcoholic extract of the leaves of myrtle herb was
evaluated at 4 concentrations including 10-80 mg/ml on four strains of pathogenic bacteria
using penetrative dissemination method together with the measuring diameter of the
growth inhibition zone; then the results were compared to four conventional antibiotics.
The minimum inhibitory and bactericidal concentrations were studied using macro dilution
method.
Results: Treatment by the concentration of 80 mg/ml extract of this herb showed the
greatest effect on the bacterium Staphylococcus aureus and Vibrio cholera serotype
Ogawa which had a significant difference with all other treatments and standard antibiotics
(p< 0.05). The extract showed no effect on the bacterium Pseudomonas aeruginosa and
just concentration of 80 mg/ml showed a little effect on E. coli and other antibiotics had no
significant effect except tetracycline which has little effect on this strain. Minimum
inhibitory concentration was 0.2 mg/ml for bacterium Staphylococcus aureus (S. aureus)
and the maximum for E.coli by 8 mg/ml.
Conclusion: This study showed that under study bacteria were more resistant to the
antibiotics and the extract of Myrtus communis leaves showed greatest antibacterial effect
against S. aureus and V. cholerae cerotype Ogawa.