Compounds in cranberry juice could be the ultimate panacea for a host of illnesses ranging from kidney infections to gastroenteritis to tooth decay.
The results of a new research by scientists at Worcester Polytechnic Institute (WPI) suggest that the cranberry may provide an alternative to antibiotics, particularly for combating E coli bacteria that have become resistant to conventional treatment.
The new findings, presented on Sunday, September 10, at the annual meeting of the American Chemical Society in San Francisco, for the first time begin to paint a detailed picture of the biochemical mechanisms that may underlie a number of beneficial health effects of cranberry juice that have been reported in other studies over the years.
Many of those studies have focused on the ability of cranberry juice to prevent urinary tract infections (UTIs), which each year affect eight million people–mostly women, the elderly, and infants--resulting in $1.6 billion in health care costs. Until now, scientists have not understood exactly how cranberry juice prevents UTIs and other bacterial infections, though they have suspected that compounds in the juice somehow prevent bacteria from adhering to the lining of the urinary tract.
The new findings reveal how the compounds interfere with adhesion at the molecular level.
The research, by Terri Camesano, associate professor of chemical engineering at WPI, and graduate students Yatao Liu and Paola Pinzon-Arango, and funded, in part, by the National Science Foundation, shows that a group of tannins (called proanthocyanidins) found primarily in cranberries affect E. coli in three devastating ways, all of which prevent the bacteria from adhering to cells in the body, a necessary first step in all infections:
They make it difficult for bacteria to make contact with cells, or from latching on to them should they get close enough.
For most of these effects, the impact on bacteria was stronger the higher the concentration of either cranberry juice or the tannins, suggesting that whole cranberry products and juice that has not been highly diluted may have the greatest health effects.
The new results build on previously published work, in which Camesano and her team showed that cranberry juice causes tiny tendrils (known as fimbriae) on the surface of the type of E coli bacteria responsible for the most serious types of UTIs to become compressed.
Since the fimbriae make it possible for the bacteria to bind tightly to the lining of the urinary tract, the change in shape greatly reduces the ability of the bacteria to stay put long enough to initiate an infection.