Background and Objectives: Food-borne pathogens are a major public health problem. Traditional culture methods for detection of them in food are simple, easily adaptable, very practical, but they can be laborious and time consuming. In this study, we eliminated culturing steps by developing a new separation method and decreased the detection time of food-borne pathogens -Salmonella enterica serovar Typhimurium, Escherichia coli O157:H7 and Listeria monocytogenes- to a few hours. Material and methods: We used alkaline water and different alkaline buffers to elute bacteria from the lettuce surface as a model of ready-to-eat vegetables. Buffers used were as follows: 1- 0.05 M glycine; 2- 0.05 M glycine -100 mM Tris base - 1% -w/v- beef extract; 3- buffer peptone water; 4- buffer phosphate saline. Each was adjusted to pH of 9, 9.5 and 10. Then the lettuce pieces were suspended into them, shacked for 30, 45 and 60 min to elute the bacteria. After elution, a multiplex PCR method for the simultaneous detection of food-borne pathogens has been described. Results: The results showed that buffer peptone water at pH 9.5 for 45 min have high ability to elute bacteria from the lettuce surface and can be detected using multiplex PCR. Conclusions: We developed a new rapid and efficient method for simultaneous separation and detection of food-borne pathogens. This method eliminates culturing stages and permits the detection and identification of target pathogens in a few hours.

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