Researchers at North Dakota State University have discovered that a mood-enhancing susbstance can help reduce the virulence of E. coli. In testing a series of chemicals on E. coli in beef broth, researchers found that a neurotransmitter called phenylethylamine (PEA) reduced the bacteria’s biofilms. “Biofilms are complex communities of bacteria that attach themselves to surfaces and also to each other,” explained Dr. Birgit Pruess, associate professor and researcher in NDSU’s Department of Veterinary and Microbiological Sciences and leader of the research. She said that biofilm formation has the potential to hinder the work of antibiotics. In addition to reducing biofilm in beef broth, Pruess, doctoral student Priyankar Samanta, master’s student Meredith Irsfeld, and 2013 master’s graduate Ty Lynnes also found that PEA reduced bacterial cell numbers on the surface of meat. Pruess said the PEA discovery was a bit of a surprise because she hadn’t known much about the substance, and there was no previous evidence that it would have this effect. “It could have been a chemical that was dangerous to humans or it could have been something that’s outrageously expensive,” she said. With PEA sold as a health supplement to fight depression and also found in trace amounts in chocolate, “We were lucky that PEA is something that people are already taking,” she added. Pruess and her team are now trying to identify what mechanism the substance uses to inhibit E. coli growth. She hopes that eventually materials and techniques can be developed with PEA to reduce harmful E. coli on our food.