Quercetin and its derivatives: chemical structure and bioactivity - a review

Quercetin is one of the major dietary flavonoids belonging to a group of flavonols. It occurs mainly as glycosides, but other derivatives of quercetin have been identified as well. Attached substituents change the biochemical activity and bioavailability of molecules when compared to the aglycone. This paper reviews some of recent advances in quercetin derivatives according to physical, chemical and biological properties as well as their content in some plant derived food.