Researchers at North Dakota State University are using a mood-enhancing substance found in trace amounts in chocolate to stunt the growth of E. coli, a bacteria that can cause serious and sometimes fatal food-borne illnesses.

The substance — phenylethylamine (PEA) — is sold as a health supplement to fight depression but also fights E. coli, inhibiting the bacteria from forming biofilms that stick to surfaces and to each other.

Biofilms are a community of bacteria, which give the bacteria strength in numbers. The E. coli biofilm is similar to plaque on teeth, Birgit Pruess, associate professor and researcher in the university’s Department of Veterinary and Microbiological Sciences, said.

Biofilms are a contributing factor in up to 80 percent of all bacterial infections. Physical removal of the biofilm is difficult, and in some cases impossible. It’s difficult to treat, so preventing it is a good option, she said.

The researchers found PEA reduces biofilms in beef broth and bacterial cell numbers on the surface of meat.

PEA doesn’t kill the bacteria but changes how the bacteria behave, making them less harmful to humans. It appears to inhibit attachment at the first contact with a surface and each other, she said.

If PEA proves effective in combating salmonella, the research could be applied to the poultry industry as well as the beef industry, she said.

Researchers tested 190 different chemicals to reduce E. coli in beef broth and plan to test up to 2,000, depending on funding, she said.

The next step is to identify the mechanism the substance uses to inhibit E. coli growth and then develop materials and techniques using PEA to reduce the harmful bacteria in food.

Those materials could include food packaging, coatings for food processing equipment or sprays for home use.

With more funding and collaboration with the food processing industry, those materials could be identified in three years. FDA and patent approval would take longer, she said.

It was a fortunate coincidence that PEA is already being taken by people and is regarded as safe for human consumption.

PEA should not be taken in combination with antidepressants without physician oversight, however. So there may be some people who shouldn’t take it, and that population would need to be identified, she said.

Pruess said the researchers were lucky that a chemical that proved effective in combating E. coli was not toxic to humans or outrageously expensive.

The research also holds opportunities for the medical profession and could be used to reduce E. coli on medical devises, such as knee and hip implants, catheters and pacemakers, she said.

The research is part of Pruess’ ongoing work to develop techniques to prevent biofilm formation. She has received a $358,750 grant through the National Institutes of Health for that research as well as additional funding for the PEA research from the North Dakota Board of Agricultural Research and Education and the North Dakota Beef Commission.

Sign up for our Top Stories newsletter

Recommended for you