Flavanones are contained in the so-called citrus bioflavonoids. Citrus bioflavonoids are a collective term for various types of flavonoids that are found primarily in the peels of citrus fruits. They contribute to the smell and taste of the fruit.
A distinction is made between aglycones and glycosides. In the case of the aglycone or genin, the alcohol residue (-OH) is sugar-free. The glycoside is a compound in which an alcohol is bound to a sugar via a glycosidic bond.
Aglycones
- Eriodictyol
- Hesperitin
- Isosacuranetin
- Liquiritigenin
- Naringenin
Glycosides
- Didymin
- Eriocitrin
- Hesperidin
- Liquiritin
- Naringin
- Narirutin
- Neoeriocitrin
- Neohesperidin
- Poncirin
The flavanones naringenin and hesperidin are present as citrus extracts – obtained from grapefruit and orange, respectively. With the consumption of orange or grapefruit juice, for example, an average of 20 mg of flavanones – including 15 mg of hesperidin, 2.1 mg of naringin and 3.6 mg of narirutin – are ingested daily in the United States. Naringenin and hesperetin have high bioavailability in this context: high plasma concentrations (6 µM naringenin and 2.2 µM hesperetin) were measured 5 hours after ingestion of the juices.
