Surface monitoring of L. monocytogenes by real‑time fluorescence and colorimetric LAMP

Listeria monocytogenes is a major foodborne pathogen affecting developing, and developed countries. The analysis of food contact surfaces in food industries is key for better controlling this pathogen. The current study focused on the development, optimization, and evaluation of a rapid and simple m...

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Detalles Bibliográficos
Autores: Ábalo, Maruxa, Lamas Freire, Alexandre, Teixeira, Carla, Prado Rodríguez, Marta, Garrido Maestu, Alejandro
Tipo de recurso: artículo
Fecha de publicación:2024
País:España
Institución:Universidad de Santiago de Compostela (USC)
Repositorio:Minerva. Repositorio Institucional de la Universidad de Santiago de Compostela
Idioma:inglés
OAI Identifier:oai:minerva.usc.gal:10347/43497
Acceso en línea:https://hdl.handle.net/10347/43497
Access Level:acceso abierto
Palabra clave:Listeria monocytogenes
Surface analysis
Loop-mediated isothermal amplification
Naked-eye detection
Stainless steel
2414 Microbiología
Descripción
Sumario:Listeria monocytogenes is a major foodborne pathogen affecting developing, and developed countries. The analysis of food contact surfaces in food industries is key for better controlling this pathogen. The current study focused on the development, optimization, and evaluation of a rapid and simple method for the detection of L. monocytogenes on stainless steel surfaces, suitable for decentralized setups, taking advantage of Loop-mediated isothermal amplification (LAMP). This was accomplished using a general pre-enrichment broth (TSB), with a simple DNA extraction based on a chelating resin, and final isothermal amplification. Two different detection strategies were tested, real-time fluorescence and naked-eye colorimetric, which were evaluated after 5, 7, and 24 h of pre-enrichment. Regardless the detection chemistry selected, after 5–7 h of preenrichment, 103 –104 CFU/cm2 were needed to obtain a positive result, while after 24 h, it was possible to detect concentrations below 10 CFU/cm2. Within each given time, all the performance parameters calculated, relative sensitivity, specificity, and accuracy, reached values higher than 80–90%; likewise, a Cohen’s k of concordance with a culture-based approach higher than 0.8. Overall, the most sensitive assay can be performed in roughly 25 h. This time-to-result outperforms commercial kits with the added value of specifically detecting L. monocytogenes instead of Listeria spp.