Development of multiplex PCR for detection of foodborne pathogens in fresh produce.

This article focuses on the development and optimization of a modified multiplex polymerase chain reaction (mPCR) assay for the simultaneous detection of three major foodborne pathogens—Escherichia coli, Salmonella, and Listeria monocytogenes—in fresh produce. The assay demonstrated high specificity and sensitivity, accurately detecting target pathogens without cross-reactivity and identifying Salmonella, L. monocytogenes, and E. coli at very low DNA concentrations. Validation using artificially inoculated kale and romaine lettuce showed reliable detection of E. coli and Salmonella at low bacterial concentrations within 6 to 18 hours, while L. monocytogenes detection was less consistent, likely due to DNA extraction challenges and matrix effects. The study highlights the assay’s potential as a rapid, sensitive tool for food safety monitoring in leafy greens, with recommendations for further optimization and broader validation to enhance detection of L. monocytogenes and applicability across diverse produce types.