Many edible plants have been used since ancient time to control microbial infections. This study was designed for evaluating the antibacterial effect of the herbal plant extracts against E.coli. The broth microdilution method was used to determine the Minimal Inhibitory Concentrations (MIC) of the studied extracts. Methanol extraction method was applied for Moringa leaves, Cucurbita pepo fruits, Cucurbita pepo seeds, Citrilluscolocynthis seeds and Citrilluscolocynthis fruits. It was found that, methanolic extract of Citrilluscolocynthis fruits had antibacterial effect on E.coli at MIC 640 µg/m. On the other hand, hexane extract of Moringa leaves Cucurbita pepo fruits, Citrillus colocynthis seeds and Citrillus colocynthis fruits did not show any inhibitory zone for E.coli. However, Cucurbita pepo seed extract showed inhibition for E.coli at MIC 640 µg/ml. Chloroform extract of Moringa leaves, Cucurbita pepo seeds and Citrilluscolocynthis seeds showed inhibition for E.coli at MIC 640 µg/ml, but the chloroform extract of Cucurbita pepo fruits and Citrilluscolocynthis fruits didn't show any inhibitory zone for E.coli. In addition, it was found that butanol extract of Moringa leaves showed inhibition for E.coli at MIC 1280 µg/ml while that of Cucurbita pepo fruit, Cucurbita pepo seeds, Citrilluscolocynthis fruits and Citrilluscolocynthis seeds had
effects on E.coli at MIC 640 µg/ml. These results confirm the traditional claims and provide promising baseline information for the potential use of the tested extracts in the fight against bacterial infections