Rutin, also calle rutoside, quercetin-3-rutinoside and sophorin, is a citrus flavonoid glycoside found in buckwheat , the leaves and petioles of Rheum species, and the fruit of the Fava D'Anta tree (from Brazil), as well as other sources. Its name comes from the name of Ruta graveolens, a plant, that also contains rutin. Rutin is the glycoside between the flavonol quercetin and the disaccharide rutinose.