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Skeletal formula of quercetin
Ball-and-stick model of the quercetin molecule
IUPAC name
Other names
Flavin meletin
3D model (Jmol)
ECHA InfoCard 100.003.807
PubChem CID
Molar mass 302.236 g/mol
Appearance yellow crystalline powder
Density 1.799 g/cm3
Melting point 316 °C (601 °F; 589 K)
Practically insoluble in water; soluble in aqueous alkaline solutions
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
N  (what is YesYN ?)
Infobox references

Quercetin /ˈkwɜːrstn/ is a flavonol found in many fruits, vegetables, leaves, and grains. It can be used as an ingredient in supplements, beverages, or foods.

While quercetin supplements have been promoted for prevention and treatment of cancer, "there is no reliable clinical evidence that quercetin can prevent or treat cancer in humans". Also, there is no evidence that consuming foods rich in quercetin reduces the risk of cancer or any other disease.

Quercetin supplements have also been promoted for the treatment of a wide spectrum of other diseases. However, the European Food Safety Authority evaluated possible health claims associated with consumption of quercetin, and found that no cause-and-effect relationship has been established for any physiological effect in human health or diseases.

Quercetin is contraindicated with some antibiotics; it may interact with fluoroquinolones (a class of antibiotics), as quercetin competitively binds to bacterial DNA gyrase. Whether this inhibits or enhances the effect of fluoroquinolones is not certain.

As paclitaxel is metabolized primarily by CYP2C8, its bioavailability may be increased unpredictably by quercetin, potentially leading to harmful side effects.

Quercetin is a flavonoid widely distributed in nature. The name has been used since 1857, and is derived from quercetum (oak forest), after Quercus. It is a naturally occurring polar auxin transport inhibitor.

Foods containing quercetin Quercetin (mg/100g of edible portion)
capers, raw 234
capers, canned 173
lovage 170
dock like sorrel 86
radish leaves 70
carob fiber 58
dill 55 (48-110)
cilantro 53
Hungarian wax pepper 51
fennel leaves 48.8
onion, red 32
radicchio 31.5
watercress 30
buckwheat 23
kale 23
chokeberry 19
cranberry 15
lingonberry 13
plums, black 12
cow peas 11
sweet potato 10
blueberry, cultivated 8
sea buckthorn berry 8
rowanberry 7
crowberry 5
prickly pear cactus fruits 5
apples, Red Delicious 4
broccoli 3
bilberry 3
tea, black or green Camellia sinensis 2
red kidney beans, raw (powdered) 0.0603 +/- 0.0307



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