95% Polyphenols. Natural Antioxidant Protection. A 100:1 concentrate guaranteed to contain a minimum of 80% Proanthocyanidins and 95% polyphenols. Unlike some grape seed products Natural Factors Grape Seed (Vitis vinifera) is not made from oven or sun-dried seeds. It is made exclusively from fresh non-GMO grape seeds separated during juice production. This method produces a high ratio of the key polyphenols. The result is a 100:1 concentrate of pure potent polyphenols. These flavonoids help to strengthen blood vessels increasing the tone and elasticity of capillary walls enhance the effect of Vitamin C and help to quench free radicals.