Bioluminescent Sensors for Onsite Non-specific Screening of Toxic Agents in Food and Water

This paper presents a non-specific detection system for quickly screening toxic and harmful contaminants in food products by utilizing the properties of naturally occurring bioluminescence in selected living bacteria. The goal of the project was to evaluate the effectiveness of using luminescent bacteria as "canaries" for rapid non-specific detection of toxic contaminants for homeland food protection and defense. Vibro fischeri was used as the specific biological sensor in this study. The bacteria was grown in marine broth and maintained between 22 and 25degC for optimal growth. Cultures were used to determine the presence of a surrogate toxicant, in this case, sodium hypochlorite (bleach) in various concentrations. Initial results show that 10% bleach quenches light emission immediately upon contact with the bacteria contained in 3 food matrices, namely: skim milk, 2% milk, and drinking water. This naturally occurring biological sensor would be useful in providing an inexpensive, highly renewable early warning system of a potentially catastrophic event. A successful system would enhance early surveillance against any intentional attack on the US food supply, including drinking water. Even in the absence of a bioterrorism event, the biological sensor would still be useful in control measures against naturally occurring or sanitation-constrained toxic substances.