Cranberry Disrupts Bacteria's Ability to Communicate, Spread and Become Virulent

Scientists from McGill University and INRS-Institut Armand-Frappier in Canada recently released a novel investigation showing that cranberry extract successfully interrupted the communication between bacteria associated with problematic and pervasive infections. The authors of the data published in Nature's Scientific Reports, Eric Déziel, professor-investigator at INRS-Institut Armand-Frappier and Nathalie Tufenkji, professor at McGill University, state that not only do the results provide insights into how cranberry compounds may work, they also have implications for the development of alternative approaches to control infections.

Previously published work has shown that the American cranberry (Vaccinium macrocarpon L) contains compounds -- such as proanthocyanidins (PACs) -- that provide meaningful antioxidant, anti-adhesion and anti-microbial properties that help fend off illness. Given this, the scientific team hypothesized that cranberries may also have an anti-virulence potential. They wanted to know if these cranberry compounds could help manage bacterial infections. By feeding fruit flies -- a commonly used model for studying human infections -- cranberry extract, the team discovered that cranberry provided flies protection from a bacterial infection and they lived longer than their cranberry-free counterparts. In essence, the cranberry extract reduced the severity of the bacterial infection.

Tufenkji elaborates on what this might mean for humans, as opposed to flies, "This means that cranberries could be part of the arsenal used to manage infections and potentially minimize the dependence on antibiotics for the global public."

To further explain cranberries' impact on bacteria, Déziel said, "Cranberry PACs interrupt the ability for bacteria to communicate with each other, spread and become virulent -- a process known as quorum sensing. The cranberry extract successfully interferes with the chain of events associated with the spread and severity of chronic bacterial infections."

Added to the evidence of cranberry's role in preventing recurrent urinary tract infections by blocking bacteria from sticking to cell walls, the current study suggests that PACs may help control the virulence or spread of potentially dangerous bacterial infections around the world.

This investigation was supported by unrestricted support from the Natural Sciences and Engineering Research Council of Canada, the Wisconsin Cranberry Board and the Cranberry Institute. The cranberry extract was provided by Ocean Spray Cranberries, Inc.