* Antioxidant Protection * GMP-Quality Assured * A Dietary Supplement Citrus bioflavonoids are a natural complement to vitamin C and are contained largely in the peels of grapefruits, lemons and oranges. Our Citrus Bioflavonoid Caps contain 30% total bioflavonoids as Hesperidin. There are many varieties of bioflavonoids available and ours includes a number of flavonols, flavones, and flavanones including: Hesperidin, Eriocitrin, Naringen, Naringenin, and Quercetin.