Detection of Escherichia Coli O157:H7 and Salmonella SPP. in Unpackaged Spices by Molecular Microbiological Analysis Method

Abstract

Aim: The aim of this study was to detection of the presence of E. coli O157:H7 and Salmonella spp. in unpackaged spices by molecular microbiological analysis method. Materials and Methods: In order to collect samples, seven cities were selected which could represent the seven geographical regions of Turkey and at least 200 g black pepper, red pepper, cumin and sumac samples were purchased from three different retail shops in each city. Retail shops’ temperature and humidity were measured. Moreover, the moisture of spices was measured by moisture analyzer. The presence of E. coli O157:H7 and Salmonella spp. were carried out using Foodproof E. coli O157:H7 and Salmonella spp. analysis kits by Real-time Polymerase Chain Reaction (RT-PCR). Results: E. coli O157:H7 was not detected in any of the samples whereas, Salmonella spp. were detected in one black pepper sample of Istanbul, one black pepper sample of Izmir, three red pepper samples and two sumac samples of Samsun. While conventional methods for detection of Salmonella spp. and E. coli O157:H7 in food requires 3-4 days to obtain the results, in this study the analysis duration by RT- PCR was 20 hours for E. coli O157:H7 (18 hours for pre-enrichment, 1 hour for DNA extraction and 1 hour PCR) and 38 hours for Salmonella spp. (36 hours for pre-enrichment, 1 hour for DNA extraction and 1 hour PCR). Conclusion: This study shows that pathogens, which threaten health and food safety, can be detected quickly and reliably by RT-PCR.