Effect antimicrobial of extract of Rosmarinus officinalis on strain of Escherichia coli

Abstract

The objective of the research work was to evaluate in vitro the antimicrobial efficacy of the crude oil extract of rosemary (Rosmarinus officinalis) on Escherichia coli. Concentrations were evaluated at 20%, 40%, 60 and 80% in dilution in 96.8% ethanol. The MIC was determined by the broth microdilution method, the bacterial inoculum of the strain ATCC 25922 was activated in the differential agar for MacConkey Enterobacteria and it was standardized to 0.5 of the MacFarland scale in spectrophotometer, having as a result that the 60% tube and 80% oil extract of rosemary did not present turbidity, which when planted on Mueller-Hinton agar determined the MBC in which no colony growth was observed. The measurement of the inhibition rings formed from the OXOID disks impregnated with the concentrations of the rosemary oil extract plus the 70% ethanol solvent was carried out and it was concluded that the 60% and 80% oil extract had the highest antibacterial effect when forming halos of 9.10 mm and 10.90 mm respectively.

Keywords

• escherichia coli
• antibiogram
• macfarland
• steam trawl
• oxoid disks
• distillation.