Application of the VPp1 bacteriophage combined with a coupled enzyme system in the rapid detection of Vibrio parahaemolyticus

For rapid and quantitative detection of Vibrio parahaemolyticus, a method combining the specific lysis of bacteriophages with a bacterial luciferase-flavin mononucleotide:nicotinamide adenine dinucleotide oxidoreductase bioluminescent system in vitro was developed. A V. parahaemolyticus detection system was established by optimizing three main influencing factors: bacteriophage titer, volume ratio of the bacteriophage to its host bacterium, and lysis time. A standard curve between the number of bacteria and the luminescence intensity of the coupled enzyme system was studied and revealed a good linear relationship. More than 107 colony-forming units (cfu)·ml− 1 bacteria in pure culture and > 108 cfu·ml− 1 bacteria in oyster samples were readily detected without pre-enrichment. Furthermore, > 100 cfu·ml− 1 bacteria in oyster samples were readily detected after 4 h of enrichment culture. Because of its rapid detection, high specificity, and simplicity in operation, this method is an effective tool for detecting living bacteria in food and environmental samples.