gnc herbal plus grape seed extract 500mg - extra strength, 60 capsules, provides antioxidant support gnc provides antioxidant support* - whole herbs are usually dried, chopped or ground into powder, and may be processed with water or alcohol for encapsulation. standardized herbal extracts are made by dissolving herbs in a solvent like water, alcohol or liquid carbon dioxide, resulting in a chemical extract. the goal of standardization is to provide uniformity of a specific constituent that may be biologically active.