An additive found in many household items and foods may actually help combat nasty strains of E. coli in an unconventional way, suggests a recent study.

Researchers, primarily from Michigan State University, conducted several experiments with polysorbate 80 and 20, which are common ingredients in everything from ice cream to flu vaccines. First, they exposed E. coli bacteria that had clumped together en masse — known in biology as a biofilm — to both chemicals in the lab, finding they successfully broke up biofilms by as much as 90 percent. In later experiments with infected mice who drank water laced with polysorbate 80, they found that while it didn’t reduce the level of E. coli in the body, it did appear to prevent the germ from causing disease. Nearly all treated mice experienced no gut inflammation or tissue damage, while the control mice became sick as usual.

“Biofilms are multicellular communities of bacteria that are usually encased in a protective slime,” explained senior author Dr. Chris Waters, a microbiologist at Michigan State, in a statement. “We found that polysorbate 80 obliterates the biofilm and takes away the E. coli’s ability to damage the host during infection. We think this is due to blocking the ability of E. coli to produce toxin.”

Research elsewhere has found that polysorbate 80 can obliterate other kinds of biofilms, such as those made of Pseudomonas aeruginosa, a common source of hospital infections. And a 2012 study in BMC Microbiology concluded it may juice up the ability of antibiotics to eradicate Helicobacter pylori, the common cause of stomach ulcers. As with the current study, it seems polysorbates do all this by poking holes in the surfaces of affected bacteria, weakening but not outright killing them and allowing antibiotics to finish the job.

This sort of combination strategy for dealing with bacteria has been hotly pursued, thanks to the growing number of infections that are becoming resistant to antibiotics. And it would be especially helpful with biofilms, since they are hardier and often form in already risky environments like hospitals. But even without antibiotics in the mix, Waters and his team believe that polysorbate 80 could play a unique role in controlling infections caused by E.coli.

“Antibiotic use can often cause more harm than good with these types of E. coli infections because it causes the bacteria to release more toxin and it drives antimicrobial resistance,” Waters said. “Our results indicate that polysorbate 80 makes this strain of E. coli harmless, without these negative side effects. This approach also doesn’t disrupt patients’ natural microbiome leading to a healthier gut.”

The strain of E. coli used by Waters’ team is a particularly nasty customer — having caused a massive 2011 outbreak that began in Germany and spread across Europe, infecting at least thousands and killing dozens.

Next on the agenda for Waters’ team? Testing polysorbate 80 under different conditions to gauge its disease-fighting potential and understanding how it wreaks havoc on biofilms.

Although making sure it can work in humans is a whole other challenge. there may not be much red tape to cut through before polysorbate 80 could be used as a drug — the Food and Drug Administration already classifies it as a GRAS (generally regarded as safe) ingredient. That said, while the amount of polysorbate 80 it normally takes to be toxic to people is astronomical, some research suggests its presence in medical products could indirectly trigger severe allergic reactions in a select few.

The study’s findings were published late last September in Biofouling.

Source: Sloup R, Cieza R, Needle D, et al. Polysorbates prevent biofilm formation and pathogenesis of Escherichia coli O104:H4. Biofouling. 2016.