Abstract: The pathogenic viable cells of Vibrio parahaemolyticus in seafood were detected using real-time polymerase chain reaction combined with ethidium bromide monoazide (EMA) dye. For pure culture, there was a negative correlation between the log number of cells and the associated Ct value in the range of 2.2 × 102 to 2.2 × 107 CFU, and the detection sensitivity of single RT-PCR (22 CFU) was slightly higher than that of EMA RT-PCR(2.2×102 CFU). For artificially contaminated oyster samples, similar results were obtained from EMA RT-PCR and plate count method, and slightly lower results from single RT-PCR. Without enrichment, only one positive sample was detected in forty-five seafood samples by EMA RT-PCR with a viable Vibrio parahaemolyticus cell of 114 CFU/g. In conclusion, EMA RT-PCR could provide a rapid, sensitive and accurate way for the quantitative detection of Vibrio parahaemolyticus in seafood.

Key words: ethidium bromide monoazide (EMA), real-time polymerase chain reaction (RT-PCR), seafood, viable cells, Vibrio parahaemolyticus detection