Hesperidin is a flavanone glycoside found in citrus fruits. Its aglycone form is called hesperetin. Its name is derived from the word "hesperidium", for fruit produced by citrus trees. Hesperidin was first isolated in 1828 by French chemist Lebreton from the white inner layer of citrus peels (mesocarp, albedo). Hesperidin is believed to play a role in plant defense.