olecular Detection of Salmonella typhi in FoodSamples by PCR Using invA Gene

Salmonella typhi is an important enteric pathogen that can be transmited via food and water. So, careful and rapid identification of this organism is very important. Today, new techniques in rapid diagnosis of pathogenic bacteria in food are important. The purpose of this study was molecular detection of S. typhi in food samples by PCR using invA gene.

After extraction of genomic DNA by two standard methods, molecular method of PCR by specific primer of invA gene on any of the standard strains of bacteria was set. Then, using the PCR method, S. typhi was detected in samples of contaminated food.

The results showed that invA gene is the suitable sequence for detection of S. typhi in contaminated foods. Also, designed PCR method in this study is a method with high sensitive (detectable copy number is 1. 89×108) and specificity for rapid detection of S. typhi in contaminated food. Discussion &

The results of this study shows that PCR method is safe, fast and sensitive for rapid detection and identification of bacteria in contaminated foods and can be an appropriate substitute method for the current and conventional methods.