| Autor: |
Cheng, Chorng-Ming, Doran, Tara, Lin, Wen, Chen, Kai-Shun, Williams-Hill, Donna, Pamboukian, Ruiqing |
| Zdroj: |
Journal of Food Protection; June 2015, Vol. 78 Issue: 6 p1119-1124, 6p |
| Abstrakt: |
Sixteen FERN (Food Emergency Response Network) member laboratories collaborated in this study to verify extension of the real-time PCR Salmonelladetection method originally designed for the single-tube Cepheid SmartCycler II and validated against the Salmonellamethod of the U.S. Food and Drug Administration Bacteriological Analytical Manualto the Applied Biosystems (ABI) 7500 FAST Real-Time PCR system multiwell plate platform. Four foods were selected for this study: chili powder, soft cheese, fish, and tomatoes; these foods represent products that are commonly analyzed for the presence of Salmonellafor regulatory purposes. Each food consisted of six uninoculated control samples, six samples inoculated with low Salmonellalevels (target 1 to 5 CFU/25 g), and six samples inoculated with high levels (target 10 to 50 CFU/25 g). All samples were tested for Salmonellausing the 24-h quantitative PCR (qPCR) method for detecting Salmonella, which utilizes modified buffered peptone water as the sole enrichment medium and an internal control for the qPCR. Each of these 18 samples was individually analyzed for Salmonellaby the collaborating laboratories using both the ABI 7500 FAST system (alternative method) and the SmartCycler II system (reference method). Statistical analysis of the data revealed no significant difference (P ≥0.05) between these two qPCR platforms except for the chili powder samples. The differences noted with chili powder (P =0.0455) were attributed to the enhanced sensitivity of the ABI 7500 FAST system compared with the SmartCycler II system. The detection limit of both qPCR methods was 0.02 to 0.15 CFU/g. These results provide a solid basis for extending the 24-h qPCR Salmonellamethod to the ABI 7500 FAST system for high-throughput detection of Salmonellain foods. |
| Databáze: |
Supplemental Index |
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