Naked-eye detection with loop-mediated isothermal amplification for P. carotovorum subsp. carotovorum in agricultural products

Pectobacterium carotovorum causing soft-rot disease requires on-site detection before the distribution of agricultural products. Loop-mediated isothermal amplification (LAMP), which is resistant to food inhibitors, is known for its high detection sensitivity for pathogens and when coupled with lateral flow immunoassay (LFA) enables visualizations. For detection of soft-rot disease, we developed a LAMP-LFA system targeting 16S ribosomal RNA, a partial sequence gene of P. carotovorum subsp. carotovorum . The LAMP-LFA was performed at 60 °C for 50 min followed by hybridization of digoxygenin-labeled LAMP amplicon and biotinylated probe. Detection sensitivity was 3.22 × 10 1 CFU/mL in pure culture, which specifically detected the target. In Chinese cabbage and potato, the target was detected up to low levels of 1.57 × 10 2 CFU/g and 1.29 × 10 2 CFU/g, respectively. This study showed potential applicability as a sensitive point-of-care system for soft-rot disease bacteria detection in agricultural products.