Background and Objective: Today, due to the occurrence of drug resistance and the ability of bacteria to develop acute infections, investigating the antimicrobial effects of herbs has been proposed. Therefore, we aimed to examine the effects of Hypericum perforatum extract and microemulsion and Aloe vera extract on Brucella bacteria.
Materials and Methods: This experimental study was carried out with the help of a hood in a biosafety level 2 laboratory. Fifty blood serum samples were cultured in BACTEC for brucellosis, and if grown, they were transferred to Brucella Agar in an anaerojar containing 10-5% CO2 for 48-72 h. Biochemical validation tests were carried out on the grown samples. Extraction was performed by a reflux (distillation) apparatus in a 1 liter balloon and a 40 cm spiral arm. Microemulsion structure was prepared by emulsifiers from the extract. Afterwards, 1, 8.4, and 2 mg/L dilutions of the aqueous extracts of Hypericum perforatum and Aloe vera were prepared, and the antimicrobial properties of these extracts were evaluated by disc diffusion, pour plate, and extraction methods on pure culture of Brucella isolated from patients.
Results: Evaluation of antimicrobial effects on the isolated Brucella strains showed that the mean diameters of the zones of inhibition in the studied strains for the of 8-1 mg/l concentrations of Hypericum perforatum extract were 36.6±2 and 18±3 mm, respectively, and for Aloe vera they were respectively 30.7±3 and 18±1 mm. None of the strains formed an inhibition zone at the 0.5 mg/l concentration. Evaluation of the effect of the extract in the well diffusion method also yielded similar results, but in the pour plate method, the effect of the extractes on the bacteria was not observed. Micoemulsion of the Hypericum perforatum extract did not have any effect because of over dilution.
Conclusion: The disk diffusion method under biosafety level 2 laboratory was highly effective, and the extract of Hypericum perforatum had the highest effect on Brucella; therefore, it is recommended for clinical studies.