Nisin isn't just an all-natural food preservative — new evidence suggests it may also pack a cancer-killing punch.
And the colorless and tasteless powder, which naturally grows on dairy products, may also defend against dangerous antibiotic-resistant bacteria like MRSA.
In a new study, researchers from the University of Michigan (UM) found that mice fed a "nisin milkshake" saw between 70 and 80 percent of their cancerous tumor cells killed after nine weeks. A past study by the same researchers found that nisin prevented the growth of several antibiotic-resistant bacterial strains.
"The application of nisin has advanced beyond its role as a food biopreservative," said lead study author Yvonne Kapila, PhD, a professor at UM, in a press release. "Current findings and other published data support nisin's potential use to treat antibiotic-resistant infections, periodontal disease and cancer."
Nisin is a type of protein released by a type of bacteria to kill off the competition. These proteins are common among the bacteria responsible for turning milk into cheese and other dairy products. It’s one of the reasons that spoiled milk is still safe to consume, while other rotten foods are not.
The mold, which has been approved by the US Food and Drug Administration (FDA) for many years, is commonly added to food products to increase their shelf-life. Some non-food products also contain nisin, including medications and creams used to fight infection.
Despite these promising findings, Dr. Kapila and team cautioned that it's still too early to tell if nisin will behave the same way in humans. So far, the cancer-killing abilities of nisin have only been tested in mice. And a similar dose scaled up for humans has not yet been developed.
Still, this may be good news, Dr. Kapila said.
"Mother Nature has done a lot of the research for us, it's been tested for thousands of years," Dr. Kapila said.
This study was published Jan. 11 in the Journal of Antimicrobial Chemotherapy.
Information on funding sources and conflicts of interest was not available at the time of publication.