Fight bacteria resistant with cranberries and antibiotics

Interaction between cranberries and bacteria discovered

The large-fruity cranberry is better known under its English name cranberry. The blueberry and cranberry relatives contain plenty of vitamins and minerals. The berry is said to have a healing effect in urinary tract infections. However, the scientific evidence has so far been lacking. Now a Canadian research team has actually demonstrated an interaction between cranberry extract and bacteria.

Canadian researchers from McGill University in Montreal wanted to find out in a study whether the ingredients of the cranberry actually work against bacteria. They brought bacteria in contact with cranberry extract in the laboratory and documented the reactions. The results were astonishing: the berries thinned the cell walls of the pathogens, making them more susceptible to antibiotics. The study was recently presented in the "Advanced Science" journal.

Cranberries put to the test

The global spread of antibiotic resistance has set humanity back for decades in the fight against bacterial infections. The excessive use of antibiotics in medicine and in cattle breeding has led to infectious diseases, which used to be easy to treat, more often end fatally. In search of new active ingredients, a Canadian research team turned to the antibacterial effect of cranberry, which is known from naturopathy, in order to scientifically test whether the said effect can be proven.

Cranberries are brimming with healthy ingredients

Cranberries are extremely popular in North America for their tart taste and healthy ingredients. They are rich in vitamin C, provitamin A, vitamin B6, vitamin K, iron, calcium, potassium, magnesium, sodium and folic acid. They also contain phytochemicals such as polyphenols and anthocyanins. In Germany, the berry is more of an exotic, but is becoming increasingly popular and is available in every major supermarket. In addition to the healthy ingredients, the large-fruity cranberry has a completely different effect. It affects bacteria, as the Canadian research group at McGill University showed.

Antibiotics make bacterial pathogens resistant

The researchers wanted to find out more about the molecular properties of the berry by treating different strains of bacteria with cranberry extract. The selected bacteria (Proteus mirabilis, Pseudomonas aeruginosa and Escherichia coli) are common pathogens of urinary tract infections, pneumonia and gastroenteritis. The germs are also known to often develop resistance when they come into contact with antibiotics. "If we treat bacteria with an antibiotic in the laboratory, they become resistant over time," says lead author Nathalie Tufenkji in a press release on the study results.

The triple antibacterial effect of the cranberry

The laboratory analyzes showed that the cranberry acted on the bacteria in three ways. First, the extract made the bacterial cell wall more permeable to the antibiotic. On the other hand, the cranberry substance interfered with a mechanism of the bacteria with which the pathogens try to get rid of harmful substances. In addition, the cranberry active ingredient prevented resistance from developing. "When we treated the bacteria with an antibiotic and the cranberry extract at the same time, no resistance developed," emphasizes Tufenkji. The researchers were very surprised by these results.

An overview of the research results

After a cranberry extract had acted on the bacteria examined, the antibiotic was able to penetrate them more easily, at the same time the bacteria had greater difficulty in getting rid of them and could not develop resistance. Antibiotics were more effective even in low doses. “We see this as an important opportunity,” emphasizes the head of research.

Where does the effect come from?

"The interaction is created by molecules called proanthocyanidins," explains Professor Éric Déziel, a co-author of the study. "There are different types of proanthocyanidins and they work together to achieve this effect on the bacteria." In another study, the team now wants to find out the optimal composition of the proanthocyanidins, which enables maximum synergy with antibiotics.

Naturopathy and modern research go hand in hand

This is the second study in a short time that examines antibacterial effects that are known from naturopathy. Just recently, an American research team took a close look at natural medicine substances that were used in the civil war due to a lack of medication to treat wound infections. For more information, read the article: Traditional Herbal Medicine Rediscovered as an Antibacterial Miracle Cure. (vb)

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Video: Why is NGS Vital to the Clearing of Chronic UTIs? MicroGenDX Minute Ep. 5 (January 2022).