Food Engineering

Researchers discover natural bacteria killer

September 7, 2011
Scientists have discovered a naturally occurring peptide that kills common foodborne bacteria.


University of Minnesota researchers have discovered and received a patent for a naturally occurring lantibiotic-a peptide produced by a harmless bacteria-that could be added to food to kill harmful bacteria like Salmonella, E. coli and Listeria.

The U. of M. scientists say this lantibiotic is the first natural preservative found to kill gram-negative bacteria, typically the harmful kind. “It’s aimed at protecting foods from a broad range of bugs that cause disease,” says Dan O’Sullivan, U. of M. professor of food science and nutrition. “Of the natural preservatives, it has a broader umbrella of bugs that it can protect against.”

The lantibiotic could be used to prevent harmful bacteria in meats, processed cheeses, egg and dairy products, canned foods, seafood, salad dressing, fermented beverages and many other foods. In addition to food safety benefits, lantibiotics are easy to digest and nontoxic, do not induce allergies and are difficult for dangerous bacteria to develop resistance against.

O’Sullivan discovered the lantibiotic by chance, while researching the genome of bacteria. He then collaborated with Ju-Hoon Lee, a U. of M. graduate student, to continue the research. The U. Of M.’s Office for Technology Commercialization is currently seeking a licensee for the technology.

Recent E. coli and Salmonella recalls emphasize the importance of finding new and harmless-to-human bacteria killers. “Salmonella burden has increased more dramatically than any other foodborne illness,” says Shaun Kennedy, director of the National Center for Food Protection and Defense. “The largest recall in 2010 for food contamination was eggs contaminated with Salmonella.”

Salmonella and E. coli, both gram-negative bacteria, account for more than half of all food recalls in the United States. According to the Centers for Disease Control and Prevention, Salmonella contributes to an estimated 28 percent of the more than 3,000 deaths related to foodborne illness each year.