PROANTHOCYANIDINS

Proanthocyanidins are oligomeric flavonoids, mainly found in grapes. They are dimers (see picture) or oligomers of catechin and epicatechin and their gallic acid esters.

Distribution

Proanthocyanidins are mainly found in the skin and seeds of grapes. They are also present in red wine. During the production of red wine, the juice is left to ferment with the seeds and skins during a few days. During this fermentation process, the formed alcohol will extract the proanthocyanidins from the seeds and skins. Other rich sources are cocoa, apples, peanuts, almonds, cranberries, blueberries and bark of the maritime pine.

Health Benefits of Proanthocyanidins

Consumption of red wine, red grape juice, grape skin and grape seeds has been linked to many health benefits. There are mainly two grape phytochemicals responsible for these benefits: proanthocyanidins and resveratrol. Proanthocyanidins are in the first place very strong antioxidants. Studies have shown that proanthocyanidins act as anti-cancer and anti-allergic agents, and that they improve heart health.

Antioxidant
Proanthocyanidins protect against oxidative damage and could reduce the damage caused by tobacco smoking, pollution and free radical form in our body during normal metabolism.

Hearth Disease
Many studies have shown that proanthocyanidins help to prevent the oxidation of LDL cholesterol, reduce blood pressure and improve fat metabolism. The inhibitory action against LDL cholesterol appears to increase with the degree of polymerization of the proanthocyanidin molecules. Proanthocyanidins may prevent cardiovascular disease by reducing the risk associated with high blood cholesterol. Tests with rabbits showed that an extract of grape seed proanthocyanidins significantly reduced the development of aortic atherosclerosis. Grape seed proanthocyanidins have a cardioprotective effect and protect the heart against myocardial injuries induced by isoproterenol, a drug used as an inhaled aerosol to treat asthma.

Anti-Cancer Studies have shown that proanthocyanidins have anti-cancer and anti-tumour activity. The study by entitled Grape Seed Proanthocyanidins Induce Apoptosis and Inhibit Metastasis of Highly Metastatic Breast Carcinoma Cells (Carcinogenesis. 2006 August) concluded that grape seed proanthocyanidins may possess chemotherapeutic activity against breast cancer.

Anti-Allergic Proanthocyanidins inhibit enzymes that produce histamine and help to ease of allergies.

Facts about Proanthocyanidins

Many plants produce proanthocyanidins in their fruits, bark, leaves and seeds to protect them from predation. Proanthocyanidins give the typical astringency to foods such as wine and teas.

Research Reviews

Protective Effect of Grape Seed Polyphenols against High Glucose-Induced Oxidative Stress.

Abstracts

Proanthocyanidins as Antioxidant

Anticancer Activity of Proanthocyanidins

Effect of Procyanidins on Anticancer Drug Doxorubicin

Synonyms

Pycnogenol, OPC, Oligomeric Procyanidins