Detection of Salmonella typhimurium and Escherichia coli in artificially inoculated Milk sample using Real Time PCR method

Abstract

Salmonella typhimurium and Escherichia coli are the bacteria the most common cause of food-borne illness. The aim of the study is to detection S. typhimurium and E. coli by Real Time PCR from milk samples. Gene targeted of S. typhimurium is pef and the E. coli is fimC. Confirmation test of all primers in contaminated milk with S. typhimurium and E. coli gave different cycle threshold (Ct) value in range 12-13. The detection limit for S. typhimurium with primer pef was in 7, 92 pg/μL and detection limit for E. coli with primer fimC in 7, 12 pg/μL. Each primer produces distinctive melting peak. The melting peak curve S. typhimurium with pef primer is 84,17°C and the melting peak curve E. coli with fimC primer is 79,97°C Based on the result of this study; all the primers were successfully applied in detecting S. typhimurium and E. coli bacteria in the milk sample quickly, sensitive and specific as well as can determine the number of bacteria accurately.