Evolution of molecular methods for microbial detection in seafood

The introduction of molecular techniques in biotechnology has supplied new approaches that could be applied for a quick and specific detection of pathogens. Since, one of the major concerns in seafood is the presence of pathogenic microorganisms, the absence of bacteria such as Salmonella, Vibrio cholerae, V. parahaemolyticus and Listeria monocyotogenes has to be granted in sea food. High quality and safety levels are required by the market to ensure that no outbreaks can affect humans health by consumption of seafood. Testing of raw material and/or final products for the presence of these pathogens using classical plate methods is time consuming and laborious. Rapid DNA based methods developed last few decades facilitate specific detection of pathogens. Techniques based on nucleic acid amplification such as PCR and qPCR showed very high sensitivity and specificity. Other techniques based on DNA hybridization can use specific labelled DNA probes, short stretches of nucleotides complementary to the target sequences, to detect quickly pathogens. In recent years, biosensors (biological components that bind or react with a target molecule and transduce this into a decetable signal) played an important role for food analysis and safety improving seafood quality. Electrochemical biosensors, optical biosensors, and acoustic biosensors have been used, due to the high sensitivity and specificity obtained. Biosensors are attractive because they can be easily used by non-specialist personnel and they allow accurate determination. they show the advantage to require tiny volumes, and to shorten the detection time which is a critical parameter for food industry in preventing food-related illnesses.