A Rapid and Sensitive LAMP Assay for the Detection of Klebsiella aerogenes in Food Matrices

Foodborne pathogens such as Klebsiella aerogenes pose a threat to food safety, highlighting the need for rapid, reliable detection methods amid rising contamination risks in production chains. In this study, a loop-mediated isothermal amplification (LAMP) assay was developed and validated to detect the histidine decarboxylase (HDC) gene of K. aerogenes. The assay was optimized for specificity and sensitivity, tested on pure bacterial genomic DNA and artificially contaminated food matrices (vegetables and meats), and evaluated against real-time PCR (qPCR). To evaluate performance under different DNA quality conditions and simulate laboratory versus on-site workflows, two extraction approaches were compared: a standard laboratory protocol yielding high-purity DNA and a crude extraction method producing low-purity DNA, mimicking the presence of inhibitors commonly encountered in routine analysis and enabling practical on-site detection where commercial kits are not feasible. The developed LAMP assay achieved maximum specificity with no cross-reactivity to related species, limits of detection of 240 fg/reaction for pure bacterial DNA and 0.4 pg/µL in K. aerogenes artificially contaminated food samples, and a reaction time under 30 min—outperforming real-time PCR in speed and robustness. This cost-effective method provides a scalable tool for near-real-time monitoring of K. aerogenes in food production, enhancing safety and enabling early outbreak detection.