Quercetin from

Boots AW, Haenen GRMM and Bast A. 2008. Health effects of quercetin From antioxidant to nutraceutical. 

I. Erlund, T. Kosonen, G. Alfthan, J. Maenpaa, K. Perttunen, J. Kenraali, J. Parantanien and A. Aro, Pharmakokinetics of quercetin from quercetin aglycone and rutin in healthy volunteers. Ear. J. Clin. Pharmacol. 56 (2000) 545-552. 

Rao, M.S., Duddeck, H., and Dembinski, R., Isolation and structural elucidation of 3,4, 5, 7-tetraacetyl quercetin from Adina cordifolia (Karam ki Gaach), Fitoterapia, 13, 353, 2002. 

McAnlis GT, McEneny J, Pearce J, Young IS. Absorption and antioxidant effects of quercetin from onions in man. 1999. Eur J Clin Nutr 53 92-96. 

Hollman PCH, van Trijp JMP, Buysman MNCP, Gaag MS, Mengelers MJB, de Vries JHM and Katan MB, Relative bioavailability of the antioxidant flavonoid quercetin from various foods in man. FEES Lett 418 152-156 (1997). 

Sekizawa and Shibamoto (1982) reported the mutagenicity of anethole present in fennel from their studies. Stich et al. (1981) examined the clastogenic activities (substances or processes which cause breaks in chromosomes) of quercetin from fennel seeds and the ubiquitous transition metal Mn2+ - individually and in various combinations. The clastogenic effects of the simultaneous application of arecoline from betel nut, plus quercetin, were greater than the action of quercetin alone. 

Trans-resveratrol (trans-3,5,4 -trihydroxystilbene) is a non-flavonoid polyphenol found in grapes, mulberries, and other food prod-ucts. It is responsible for the antioxidant activity of red wine. Intake of moderate amount of red wine has been found to reduce the risk of cardiovascular diseases. In addition to antioxidant activity, resveratrol could inhibit platelet aggregation, and showed anticancer activity. The phenoxyl radicals of resveratrol produced during oxidation by hydroxyl radicals, one-electron oxidants, and peroxyl radicals showed absorption maximum at 410 nm (Fig. I). Reports indicate that trans-resveratrol is a better radical scavenger than vitamins E and C and its activity is similar to that of the flavonoids epicatechin and quercetin. From the comparison of the spectral and kinetic properties of the transients derived from trans-resveratrol and its analogues, it could be concluded that in the neutral and acidic solutions, the para-hydroxy... 

Fig. (1). Quercetin from Achyrocline satureioides and Pterocaulon polystachium.

Erlund I, Kosonen T, Alfthan G, Maenpaa J, Perttunen K, Kenraah J, Parantainen J, Aro A. Pharmacokinetics of quercetin from quercetin aglycone and rutin in healthy volunteers. Eur J Clin Pharmacol 2000 56 545-553. 

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