Sambucol One-A-Day Gel Caps Sambucol Black Elderberry Extract Gel Capsules: * Help support the immune system * Have high antioxidant levels to protect cells * Are scientifically tested. The Flavonoids present in Sambucol Black Elderberry Extract Gel Capsules are among the most potent naturally occurring antioxidants available. Sambucol was developmed by a world-renowned scientist who recognized the potential of the antioxidants present in the black elderberry. Sambucol has been laboratory tested. Sambucol has been used by millions of people worldwide.