Multiplex PCR rapid detection for pathogenic bacteria in milk powder
To establish a multiplex PCR method for the simultaneous detection of pathogenic bacteria such as Enterobacter sakazakii,Staphylococcus aureus and Bacillus cereus in milk powder,three pairs of oligonucleotide primers were designed according to Enterobacter sakazakii ompA gene,Staphylococcus aureus nuc gene and Bacillus cereus hblA gene.They were used to amplify the special DNA sequences by multiplex PCR and the reaction conditions were optimized.The results showed that the multiplex PCR assay amplified three specific target channels of 514 bp,156 bp and 235 bp.Without bacterial enrichment,the sensitivities of the multiplex PCR for Enterobacter sakazakii,Staphylococcus aureus and Bacillus cereus were 103 cfu/mL,and the detection limits of the multiplex PCR for Enterobacter sakazakii,Staphylococcus aureus and Bacillus cereus in milk powder were 104 cfu/g.This multiplex PCR method was accurate,fast and effective and provided a new approach for detecting Enterobacter sakazakii,Staphylococcus aureus,and Bacillus cereus in milk powder.