phytochemical analysis of garlic hydro-alcoholic extract and evaluation of its anti-bacterial effect on enterohemorrhagic escherichia coli in vitro and ex vivo

Background and objectives: garlic is a medicinal plant with various health promoting properties including antimicrobial effects. in this study, we investigated in vitro antibacterial effects of garlic hydro-alcoholic extract against enterohemorrhagic escherichia coli (ehec).methods: garlic hydro-alcoholic extract was prepared by maceration method. phytochemical analysis of the extract was carried out using gas chromatography-mass spectrometry. minimum inhibitory concentration (mic) of the extract against ehec was determined by micro-dilution assay. cytotoxic effect of the garlic extract on human colon adenocarcinoma cell line (sw480) was assessed using mtt assay. micro-dilution assay was also used to determine the mic of the extract against ehec when co-cultured with sw480 cells. results: the amount of organosulfur in garlic extract was 70.91% and the most common organosulfur compounds were trisulfide, di-2-propenyl (34.8%) and diallyl disulfide (14.83%). the mic of garlic hydro-alcoholic extract on ehec alone and when co-cultured with sw480 was 12.5 mg/ml. concentrations of 12.5 mg/ml and 25 mg/ml of the extract significantly reduced the viability of sw480 cells compared to control and concentration of 6.25 mg/ml of garlic extract (p <0.0001). conclusion: the garlic hydro-alcoholic extract has inhibitory effects on ehec in vitro. therefore, it can be considered a suitable candidate for controlling infections caused by ehec.