PMA-Based LAMP Assay Targeting blaCARB-17 for Accurate Detection of Viable Vibrio parahaemolyticus Cells from Aquatic Foods

Vibrio parahaemolyticus is a major pathogen responsible for bacterial gastroenteritis associated with seafood in temperate and tropical marine and coastal waters worldwide. Detection of viable bacterial cells is crucial for food safety control. In this study, a PMA-LAMP method was developed and evaluated for detecting viable V. parahaemolyticus in aquatic products. Both live and dead cells were treated with PMA in dark for 10 min and subsequently exposed to a 650 W halogen lamp for 10 min. The DNA was prepared and amplified by PMA-LAMP. The primers which targeted six distinct regions in the bla_CARB-17 gene of V. parahaemolyticus were designed for the PMA-LAMP assay. The results showed that the treatment with 15.7 µM of PMA in dark for 10 min and a further exposure to light for 15 min was the optimum condition for PMA-LAMP to detect viable cells from V. parahaemolyticus. A total of 206 control strains were used to evaluate the specificity. The PMA-LAMP assay exhibited 100% specificity, without cross reaction with the tested non-V. parahaemolyticus cells. The limit of detection (LOD) for the PMA-LAMP assay was approximately 1.6 CFU/mL, with high sensitivity. This PMA-LAMP could contribute to the rapid, reliable, and simultaneous detection of viable V. parahaemolyticus in aquatic foods.