(n.) A glucoside extracted from the bark of the oak (Quercus) as a bitter citron-yellow crystalline substance, used as a pigment and called quercitron.
Example Sentences:
(1) Further, quercetin and quercitrin elevated the intracellular level of cAMP, whereas hesperidin and rutin did not alter the cAMP level.
(2) The known quercetin glycosides, quercetin 3-gentiobioside, isoquercitrin, quercitrin, together with the known kaempferol glycosides, astragalin and afzelin, were also characterized.
(3) Among the flavonoids tested, quercetin, kaempferol, myricetin, chrysin, quercitrin, and morin were potent inhibitors of xanthine oxidase; their inhibition rates (%) were 80, 70, 69, 62, 59, and 51 at 100 microM (except chrysin at 50 microM), respectively.
(4) There was remarkable variation of contents of quercitrin among the plants on different host trees.
(5) Rutin and quercitrin are hydrolysed to quercetin, and robinin is hydrolysed to kaempferol, by faecal flora from healthy subjects.
(6) Cytosolic and microsomal metyrapone reducing enzymes are distinguished by their inhibitor sensitivity to phenobarbitone and quercitrin and thus can be characterized as aldehyde and ketone reductases according to the inhibitor subclassification of the aldo-keto reductase family.
(7) Four chemical constituents were isolated from the stems and leaves of Illicium dunnianum: beta-sitosterol (I), 1-triacontanal (II), quercitrin (III) and shikimic acid (IV), and identified on the basis of spectral analysis.
(8) Among them, 1 showed the highest inhibitory activity, being about 6 times more potent than quercitrin, which is a known natural inhibitor of AR.
(9) It is believed that the therapeutic action of quercitrin could be caused by restoration of local circulation deranged in animal sensitization.
(10) Cell-free preparations (fecal preparations) from these cultures were then incubated with rutin or quercitrin.
(11) Six compounds have been isolated from the leaves of Euphorbia hirta and identified as gallic acid, quercitrin, myricitriu, 3,4-di-O-galloylquinic acid, 2,4,6-tri-O-galloyl-D-glucose and 1,2,3,4, 6-penta-O-galloyl-beta-D-glucose on the basis of physicochemical and spectroscopic methods.
(12) The flavonoids quercetin, quercitrin (quercetin-3-L-rhamnoside) and apigenin exhibit antiviral activity against these herpesviruses, and acyclovir is currently one of the most effective antiherpetic agents.
(13) The KI's for quercitrin and NAP-HEX-Q, both non-competitive inhibitors, are 0.6 uM and 0.5 uM, respectively.
(14) Quercetin, quercitrin, and myricitrin are significantly more potent than the previously known aldose reductase inhibitors.
(15) Quercetin, morin, kaempferol, fisetin, myricetin, quercitrin and rutin were mutagenic in the histidine reversion system with the frameshift strain TA98.
(16) Previously, these compounds and other polyphenols were assayed as in vitro antioxidants by their abilities to inhibit the tert-butyl hydroperoxide (t-BOOH)-initiated chemiluminescence of mouse liver homogenates, and the IC50 (microM) values were as follows: (+)-catechin, 3; eriodyctiol, 9; myricetin and 4,2',4'-trihydroxy-6'-metoxychalcone, 15; 3,4-dicaffeoylquinic acid, 20; isochlorogenic acid, 30; caffeic acid, 5,6,3'-trihydroxy-7,4'-dimethoxyflavone and cynarin, 50; chlorogenic acid and apigenin, 150; quercetin, pedalitin, sylimarin and quercetin-3-methyl ester, 200; 7,4'-dihydroxy-5-methoxyflavonone and kaempferol-3,7-dirhamnoside, 500; quercitrin, 900; and galangin-3-methyl ether, genkwanin, hesperidin, ombuoside, phloridzin, quinic acid, rhoifolin, rutin and sophoricoside, greater than 1 mM.
(17) Human fecal cultures, induced with either of the flavonols, quercitrin or rutin, were grown in the presence of various concentrations of chenodeoxycholic acid, deoxycholic acid or cholic acid.
(18) The enzyme activity was inhibited by 5,5'-dithiobis(2-nitrobenzoic acid), p-chloromercuribenzoic acid, N-ethylmaleimide, iodoacetamide, dicumarol, quercitrin, and disulfirum.
(19) Minor positive or negative effects were obtained with quercitrin, protocatechuic acid, grass juice, anethole and agaricinic acid.
(20) The known flavonoids quercitrin, quercetin, myricitrin and myricetin were found to be responsible for the xanthine oxidase inhibitory action of the plant extract.
Quercitron
Definition:
(n.) The yellow inner bark of the Quercus tinctoria, the American black oak, yellow oak, dyer's oak, or quercitron oak, a large forest tree growing from Maine to eastern Texas.
(n.) Quercitrin, used as a pigment. See Quercitrin.