Proanthocyanidin Complex. Suitable for Vegetarians and Hypoallergenic. Pycnogenol® is a natural plant product made from the bark of the European coastal pine Pinus maritima. Pycnogenol is rich in proanthocyanidins a special class of water-soluble antioxidant flavonoids which are excellent free radical scavengers. Proanthocyanidins are believed to play an important role in maintaining good health.