Polymerase Chain Reaction Assay Coupled with Fluorescence Detection on Microwell Plates for Listeria monocytogenes in Foods
| Autor: | Alma E. Inzunza, José Gil Sánchez, Christian Oste, Raul J. Cano, Dawn M. Norton |
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| Rok vydání: | 1995 |
| Předmět: |
Gel electrophoresis
Biology medicine.disease_cause Microbiology Molecular biology Fluorescence spectroscopy law.invention Guanidinium thiocyanate chemistry.chemical_compound chemistry Listeria monocytogenes law medicine biology.protein Primer (molecular biology) Ethidium bromide Polymerase chain reaction Polymerase Food Science |
| Zdroj: | Journal of Food Protection. 58:614-620 |
| ISSN: | 0362-028X |
| Popis: | This study evaluates a polymerase chain-reaction assay coupled with fluorescence detection (PCR-FD) in microwell plates for Listeria monocytogenes in dairy and food samples. Guanidinium thiocyanate/silica-extracted cultures and milk and dairy-food samples were used as templates for a PCR assay in microwell plates, with a primer pair that amplifies a 221 bp segment of the internal transcribed spacer (ITS), in the presence of 0.5 μg/ml of ethidium bromide. Fluorescence of the PCR products was measured with a CytoFluor 2300 fluorescence measurement system (Millipore Corporation, Bedford, MA). The lowest level of detection of the assay was 10 to 100 CFU. A total of 326 food samples were tested, both by culture and by PCR-FD. The overall sensitivity of the PCR-FD assay was 95.2% and the specificity was 89.9%. Positive and negative predictive values were 74.8% and 99.4%, respectively. Based on the results obtained in this study it appears that the PCR-FD assay described here can be useful for screening a large number of milk and dairy-food samples for contamination by Listeria monocytogenes . |
| Databáze: | OpenAIRE |
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