combined with a multipathogen enrichment procedure
could reliably and effectively detect the five major foodborne
pathogens.
The detection method contained an enrichment procedure
to enhance detection of pathogens in samples.
Potential inhibitory substances in foods, including fats,
glycogen, organic and phenolic compounds, can affect the
PCR (O’Regan et al. 2008). The overnight pre-enrichment
step (in SSSLE) was required to increase the number of
viable cells and to effectively dilute inhibitory substances
present in the sample.
For development of the multiplex PCR assay, designing
primers for the five targets is very crucial. It is reported
that nearly 2000 Salmonella serovars contain the invA
gene, which is a virulence gene encoding an invasion protein.
Generally, the invA gene has been proven to be Salmonella-
specific (D’Souza et al. 2009; Suo et al. 2010),
which was also verified to exist only in the Salm. Enteritidis
tested in this study and not in the other isolates
tested. It has been proved that the EHEC eaeA gene
encodes an outer membrane adhesin (intimin), which
mediates intimate attachment to host cell and is essential