Proanthocyanidins are a particular class of polyphenols consisting largely of oligomers of catechin, epicatechin and gallic acid, linked together to form an ether (or ester) bond.
These molecules are found in many plant species and are called proanthocyanidins because under oxidizing conditions they can depolymerize, oxidizing to anthocyanidins.These are colored polyphenolic compounds, the most common of which is the cyanidin found in blueberries, grapes, apples, radicchio and raspberries and which takes on colors ranging from deep red to cobalt blue depending on pH.

In nature, these molecules play an important defensive function for the plants that produce them, protecting them from infection and predators.[1]

Any polymers also formed from the monomers of proanthocyanidins are named tannins and are also of fundamental importance medically by virtue of their anti-inflammatory and antimicrobial properties.[2,3] Furthermore, it is known in the literature that gallic acid, one of the basic monomers of tannins and proanthocyanidins, is able to exert broad-spectrum antimicrobial activity[4,5]. We can therefore assume similar behavior from the oligomers it forms with catechin and epicatechin.

Where are Proanthocyanidins extracted from?

A recent study highlights how, for example, proanthocyanidins from larch bark extract are toxic to common bacterial pathogens such as Staphylococcus aureus because they destroy its cell wall and cell membrane, preventing the proper production of proteins necessary for the bacterium to function. They also bind to bacterial DNA, preventing its reproduction.[6]

Similar conclusions can be reached by considering other phytoextracts containing such molecules, such as extracts of pine needles [7] or maritime pine bark[8], all of which show significant antimicrobial activity.

How do they act to counter bacterial infections?

In addition to exhibiting directly toxic activity on bacterial species, tannins and proanthocyanidins can also interact with biofilms created by the bacteria themselves as a protective mechanism, damaging them. A biofilm is a film, formed of polymeric material, usually polysaccharides, that envelops and protects one or more bacterial colonies, normally of different species and also producing secretions of an adhesive nature necessary to adhere to the substrate of interest. It is considered an established fact that most of the infections reported in Western countries are caused by multi-species biofilms rather than single bacterial infections.[9]

Various phytoextracts containing proanthocyanidins have been shown to inhibit biofilm formation or their adhesion to the substrate in the case of already formed biofilms. This is especially important especially against antibiotic-resistant bacteria, since in some cases such resistance arises precisely from the formation of biofilms, which make it more difficult for antibiotic molecules to interact with the target bacteria. Furthermore, although the biochemical mechanism that causes it is not exactly clear, there is experimental evidence that the proanthocyanidins and tannins are able to reduce the resistance of both Gram-negative and Gram-positive bacteria. [10][11]

This interaction is probably due to the previously mentioned fact that in some bacteria these molecules are known to prevent transcription of the bacterial DNA, thereby also preventing the functionality of bacterial enzymes used to defend against antibiotics and increasing the effectiveness of common antibiotic treatments that would otherwise already be largely rendered useless by the spread of genes for antibiotic resistance.

Is there a specific and safe solution?

Because of this, an increase in the use of phytoextracts containing Proanthocyanidins and polyphenols is desirable in the therapy of acne, skin and urinary tract infections in the near future. To stay ahead of the curve, research Wikenfarma has developed Dedalox, a nutraceutical specific to strengthen the immune system and fight ongoing inflammation and bacterial infections thanks to proanthocyanidins: unlike other similar products on the market, which are usually very heavy to dispose of and endure, Dedalox hasno side effects and is therefore the safest option for treating infections and strengthening the immune system.