Establishment of a Dual Enzymatic Recombinase Amplification Method for Rapid Detection of Foodborne Pathogens in Infant Formula Powder

Abstract

For quick and multiple detection of the contamination of foodborne pathogens in infant milk powder, a dual enzymatic recombinase amplification (ERA) method for the rapid detection of Cronobacter, Salmonella, Listeria monocytogenes and Staphylococcus aureus were established in this study. Firstly, specific and efficient primers and probes were selected for these foodborne pathogens. Then, two groups of dual-ERA systems were established and optimized. The minimum detection limit was 10-2 ng/μL for Salmonella, L. monocytogenes and S. aureus, and 1 ng/μL for Cronobacter. The results of simulated contamination test showed that the four foodborne pathogens could be detected simultaneously after 6 hours of enrichment culture at an initial contamination level of 1 CFU/mL. When this method and real-time polymerase chain reaction (PCR) were used to detect commercial infant milk powder, consistent results were obtained, which confirmed the accuracy and reliability of the dual-ERA method. This method could simultaneously detect the four foodborne pathogens in about 20 minutes. Compared with the traditional method and real-time PCR, the detection efficiency was significantly improved, which is of great significance for promoting the rapid screening of foodborne pathogens.

Keywords

• enzymatic recombinase amplification; cronobacter; salmonella; listeria monocytogenes; staphylococcus aureus