Quercitrin (QT)

Quercitrin is a glycoside formed from the flavonoid quercetin and the deoxy sugar rhamnose. Austrian chemist Heinrich Hlasiwetz (1825-1875) is remembered for his chemical analysis of quercitrin. Quercitrin is a constituent of the dye quercitron. It can be found in Tartary buckwheat (Fagopyrum tataricum) and in oaks species like the North American white oak (Quercus alba) and European red oak (Quercus robur). It is also found in Nymphaea odorata or Taxillus kaempferi. The enzyme quercitrinase catalyzes the chemical reaction between quercitrin and H2O to yield L-rhamnose and quercetin. Quercetin is a common antioxidant flavonoid found in vegetables, which is usually present in glycosylated forms, such as quercitrin (3-rhamnosylquercetin). Previous in vitro experiments have shown that quercetin exerts a bigger effect than quercitrin in the down-regulation of the inflammatory response.