Establishment of a multiple PCR method for detection of Enterobacter sakazakii and Staphylococcus aureus in powdered milk

Objective To establish a multiple PCR method for detection of common pathogenic bacteria such as Enterobacter Sakazakii and Staphylococcus aureus in powdered milk.Methods Two pairs of oligo-nucleotide primers were designed and synthesized to amplify the special DNA sequences by multiple PCR.Moreover,the reaction conditions of multiple PCR were optimized and the method was put in practice.Results The results showed that the multiple PCR obtained specific amplicons of expected sizes,282bp for Enterobacter Sakazakii,484bp for Staphylococcus aureus by using the two pairs of primers.Under the optimized reaction conditions,the detection limits for DNA template were 105CFU/ml.Conclusion The multiple PCR assay was a specific,sensitive,rapid and reliable method for detecting Enterobacter Sakazakii and Staphylococcus aureus.