A common food additive may be interfering with our gut health, study finds

A common preservative found in sausages is suspected to damage bacteria required for gut health (Pexels/Pixabay)

A new study suggests that a commonly used food preservative may interfere with microbial gut bacteria required to keep us healthy.

Lantibiotics, a modified chain of amino acids that is added to food to prevent the growth of bacteria, is used in everything from beer and sausage to cheese and dipping sauces, according to the research, which was published in ACS Chemical Biology by researchers with the University of Chicago.

Nisin, a popular type of lantibiotic, is produced by bacteria that live in the mammary glands of cows, and the research suggests that it could affect pathogens and commensal gut bacteria in humans.

"Nisin is, in essence, an antibiotic that has been added to our food for a long time, but how it might impact our gut microbes is not well studied," study author Zhenrun Zhang said in a press release.

"Even though it might be very effective in preventing food contamination, it might also have a greater impact on our human gut microbes," he said.

Zhang and his colleagues evaluated a public database of human gut bacteria genomes in order to identify genes that produce six different gut-derived lantibiotics that are similar to nisin. They then produced versions of these lantibiotics to test their effects on both pathogens and commensal gut bacteria. These lantibiotics killed pathogens and commensal bacteria, according to the study.

"This study is one of the first to show that gut commensals are susceptible to lantibiotics, and are sometimes more sensitive than pathogens," Zhang said in the release. "With the levels of lantibiotics currently present in food, it's very probable that they might impact our gut health as well."

Researchers also assessed the molecular structure of lantibiotics to better understand how to use their antimicrobial properties "for good," the study says, with findings suggesting that they could help with antibiotic-resistant infections.

"It seems that lantibiotics and lantibiotic-producing bacteria are not always good for health, so we are looking for ways to counter the potential bad influence while taking advantage of their more beneficial antimicrobial properties," Zhang said in the release.