Recent Developments in Molecular Detection of Food-Borne Disease Bacteria and GMOs

Abstract

The polymerase chain reaction (PCR) constitutes a powerful method for rapidly detecting low numbers of pathogenic and toxigenic bacteria in complex food matrices. Recent developments have resulted in the ability to detect as low as 1 CFU of Salmonella enterica in a 25g sample of ground beef within 4.5 hrs without enrichment. Isothermal DNA amplification such as loop mediated DNA amplification (LAMP) results in ˜1,000 times greater amplicon yield compared with the PCR and has the additional advantage in that a simple temperature controlled water bath is the only piece of equipment needed. These innovations have the potential to eliminate most costly recalls and related illnesses by allowing raw food processors to detect the presence of pathogens in products well before shipment. The development of droplet digital PCR (ddPCR) has allowed the presence of very precise levels of genetically modified organisms (GMOs) to be determined to the second decimal point, which the PCR is incapable of achieving. This article deals in-depth with these recent developments.

Key words:

• bacterial pathogens
• bacterial toxin genes
• DNA based detection
• food borne pathogens
• molecular detection
• pathogenicity genes
• polymerase chain reaction