A polymerase chain reaction procedure for the detection of Salmonella spp. within 24 hours.
Salmonella spp. are one of the most important groups of food-borne pathogens worldwide. Conventional methods for the detection of Salmonella spp. in foodstuffs are generally cumbersome and time consuming. Whereas various more rapid detection methods have been developed over the past few years, there is currently no reliable true 24-hour detection method available. We report here a reliable Salmonella PCR detection method yielding results within 24 h. Chicken samples were preenriched in buffered peptone water (BPW) for 6 h. The DNA was extracted using phosphate-buffered saline (PBS) and then heated at 95 degrees C for 10 min. The Salmonella-specific primers ST11 and ST15 were used to amplify a 429-bp region specific to all Salmonella spp. This approach proved to be sufficient for the reliable detection of Salmonella spp. from both artificially and naturally contaminated poultry samples. The characteristic 429-bp PCR product was obtained in artificially contaminated samples with a detection limit of 50 CFU. A variety of chicken samples confirmed to harbor Salmonella spp. by conventional culture methods tested positive by our 24-h procedure, whereas no detectable amplification product was detected in those samples testing negative by culture methods. This method proved to be an excellent tool for the rapid and sensitive detection of Salmonella spp. from poultry samples using a specific primer set (ST11 and ST15) after only 6 h of preenrichment.
Gouws
P A
PA
Department of Microbiology, University of the Western Cape, Bellville, South Africa. pieter@mbiol.uwc.ac.za
Visser
M
M
Brözel
V S
VS
D000818:Animals; D002645:Chickens / Q000382:microbiology*; D016133:Polymerase Chain Reaction; D012475:Salmonella / Q000302:isolation & purification*; D013997:Time Factors