Proanthocyanidins are classified as polyphenol flavanols within the Proanthocyanidin category. They are prevalent in various plants like cranberries, blueberries, and grape seeds. Preliminary research explores their potential to reduce the risk of urinary tract infections (UTIs) through the consumption of cranberries, grape seeds, or red wine. Apples, particularly the Red Delicious and Granny Smith varieties, contain approximately eight times the proanthocyanidin found in wine. Oligomeric proanthocyanidins (OPC), referring to dimer and trimer polymerizations of catechins, are common in the human diet and found in grape seeds, red wine, cocoa, nuts, Prunus fruits, and more. Proanthocyanidins are under investigation for their potential impact on coronary heart disease and overall mortality. They also influence the aroma, flavor, mouthfeel, and astringency of red wines. Widely distributed in common foods like apple skin, broccoli, olives, onions, tea, cinnamon, parsley, citrus fruits, and chocolate, proanthocyanidins form a beneficial group of plant flavonoids. The most active ones are those bound to other proanthocyanidins, collectively referred to as procyanidolic oligomers (PCOs) or oligomeric proanthocyanidins (OPCs).
The list of Proanthocyanidins includes: * Procyanidin A1 * Procyanidin 2 * Procyanidin B1 * Procyanidin B2 * Procyanidin B3 * Procyanidin B4 * Procyanidin B5 * Procyanidin B6 * Procyanidin B7 * Procyanidin B8 * Procyanidin C1 * Procyanidin C2