Grape Seed Standardized Extract 100 mg, 200 Capsules, NOW FoodsNOW Grape Seed Extract Antioxidant Protection 100 mg Standardized Extract. 90% Polyphenols including OPC's. Cardiovascular and Immune Health. Vegetarian Vegan Product. NOW Grape Seed Extract is a highly concentrated natural extract containing a minimum of 90% Polyphenols, including OPC's (Oligomeric Proanthocyanidins), the beneficial antioxidant compounds found in Grape Seeds. Grape Seed Extract and OPC's have been the subject of numerous scientific