Abstract:

Abstract:Objective To establish a rapid,specific and sensitive method for the detection of Helicobacter pylori,and provide an effective detecting evidence for Helicobacter pylori. Methods A pair of primers and probe correspnding to the urease gene for real time PCR were designed according to Primer Express 3.0 software,similar sequences were searched by Blast method,and the excellent primers and probe were selected. DNA from common bacterial pathogens such as Escherichia coli,Staphylococcus,Listeria monocytogenes,Campylobacter and Salmonella in food was used for specific test;the counted Helicobacter pylori in bacterium suspension and the bacterium and milk mixture were serially diluted,the DNA was extracted for  real time PCR amplification,the sensitivity of method was tested. The practicability of the method was demonstrated through the detection of the artificial contaminative samples by real time PCR. Results The primers and probe according to urease gene could only amplify Helicobacter pylori DNA,but not  other reference bacterium DNA. Helicobacter pylori from the artificial contaminative samples could be amplified by the method. It can detect 3 CFU/mL of Helicobacter pylori. Its sensitivity was sufficient to detect 3 CFU/mL of Helicobacter pylori. The method was enough rapid to finish detection in 4 d.Conclusion Real time PCR can rapidly and accurately detect the Helicobacter pylori contamination in food with high specificity and sensitivity.

Key words: Helicobacter pylori;urease gene;real time PCR;food