ABSTRACT
Usage of medicinal plants for treatment of pathogenic diseases is one of the most promising methods, which have minimum side effects. The strains of E.coli 0157 are the most dangerous gastrointestinal tracts pathogens causing death worldwide. Therefore, a medicinal plant extract with potential for treatment of this disease would be quite effective medics. In the present study, the effect of plant extracts on the different phases of bacterial growth was precisely determined using spectrophotometery, besides routine methods such as MIC, drop plate and disc plate. To peforming this study, E.coli 0157 [NCTC1290] was obtained from the university of Aberdeen, and following the initial characterization of the bacterium, the different phases of bacterial growth were investigated in the presence of the plant extracts of Eucalyptus globulus, Juglans regia and Vitex angus castus. The results showed that the alcoholic plant extracts of E.globulus and J. regia had no significant influence on the growth of above strain of E.coli. However, the extract of V. angus custus had an inhibitory effect on bacterial growth 4-11h after inoculation, while such effect was not observed at the early stages of bacterial growth. These results could provide a better understanding and perception of the antimicrobial effects of plant medicines on bacterial growth phases, which facilitates their applications