Quercetin
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Quercetin | |
---|---|
Systematic name | Quercetin |
Chemical formula | C15H10O7 |
Molecular mass | 302.236 g/mol |
Density | 1.799 g/cm3 |
Melting point | 316 °C |
Boiling point | xx.x °C |
CAS number | 117-39-5 |
SMILES | xxxxx |
Disclaimer and references |
Quercetin is a flavonoid that forms the "backbone" for many other flavonoids, including the citrus flavonoids rutin, hesperidin, naringin and tangeritin. Quercetin is found to be the most active of the flavonoids in studies, and many medicinal plants owe much of their activity to their high quercetin content. Quercetin has demonstrated significant anti-inflammatory activity because of direct inhibition of several initial processes of inflammation. For example, it inhibits both the manufacture and release of histamine and other allergic/inflammatory mediators. In addition, it exerts potent antioxidant activity and vitamin C-sparing action.
Together with rhamnose, it forms a glycoside quercitrin.
Quercetin also shows remarkable anti-tumour properties. A recent study in the British Journal of Cancer shows that when treated with a combination of quercetin and ultrasound at 20 KHz for 1 minute duration, skin and prostate cancers show a 90% mortality within 48 hours with no visible mortality of normal cells. Note that ultrasound also promotes topical absorption by up to 1,000 times making the use of topical quercetin and ultrasound wands an interesting proposition.
Quercetin may have positive effects in combating or helping to prevent cancer, prostatitis, heart disease, cataracts, allergies/inflammations, and respiratory diseases such as bronchitis and asthma.
Foods rich in quercetin include apples, black & green tea, onions (higher concentrations of quercetin occur in the outermost rings[1]), red wine, red grapes, citrus fruits, broccoli & other leafy green vegetables, cherries, and a number of berries including raspberry, bog whortleberry (158 mg/kg, fresh weight), lingonberry (74 and 146 mg/kg), cranberry (83 and 121 mg/kg), chokeberry (89 mg/kg), sweet rowan (85 mg/kg), rowanberry (63 mg/kg), sea buckthorn berry (62 mg/kg), and crowberry (53 and 56 mg/kg).[1] A study[2] by the University of Queensland, Australia, has also indicated the presence of quercetin in varieties of honey, including honey derived from eucalyptus and tea tree flowers.[3]
In plants, it is a naturally-occurring polar auxin transport inhibitor.
[edit] See also
[edit] References
- ^ (1999) "Content of the Flavonols Quercetin, Myricetin, and Kaempferol in 25 Edible Berries". Journal of Agricultural Food Chemicals 47 (6): 2274 -2279. DOI:S0021-8561(98)01106-6 10.1021/jf9811065 S0021-8561(98)01106-6. Retrieved on 2006-10-28.
[edit] External links
- BerkleyWellness.com Quercetin article (a publication of the University of California, Berkeley)
- UMM Quercetin Info Page (University of Maryland Medical Center Website)
- Eyes right for a cup of tea UK Institute of Food Research article on how quercetin can help prevent cataracts.
- Plant foods for health protection article by the Institute of Food Research (Norwich, United Kingdom)
- Scanning Electron Micrograph image of quercetin crystals derived from onion
- Possible Interactions with: Quercetin Quercetin might enhance the effects of two chemotherapy medications
- Quercetin Info from the Cedars-Sinai Medical Center, Los Angeles.
- "Genetic Analysis of Quercetin in Onion (Allium cepa L.)" article from The Texas Journal of Agriculture and Natural Resource 16:24-28 (2003).
- "An apple a day could help protect against brain-cell damage" article at Cornell University website (originally published 2nd December 2004).
Categories: Flavonoids | Nutrients | Nutrition | Botany | Antioxidants