Background: Flavonoids are effective antioxidants and may protect against several chronic diseases. Objective: The association between flavonoid intake and risk of several chronic diseases was studied. Design: The total dietary intakes of 10 054 men and women during the year preceding the baseline examination were determined with a dietary history method. Flavonoid intakes were estimated, mainl...

OBJECTIVES Quercetin is a flavonoid and an important dietary constituent of fruits and vegetables. In recent years, several pharmacological activities of quercetin, such as its neuroprotective activity and, more specifically, its anti-convulsant effects in animal models of epilepsy, have been reported. This study evaluated the role of quercetin pretreatment on gene expression of γ-amino butyric...

Quercetin is one of the most abundant naturally occurring flavonoid and is associated with a wide range of biological activities, such as antioxidant, antiinflammatory and anticancer activities. However, there are multiple problems associated with the bioavailability of quercetin, thereby restricting its use. Taking this into consideration, the structure of quercetin was modified by removal of ...

AbstractIntroduction: Parkinson's disease (PD) is a neuropathological disorder involving the degeneration of dopaminergic neurons in the substantia nigra, with the subsequent loss of their terminals in the striatum. Quercetin, a natural flavonoid, is a strong antioxidant and radical scavenger. Therefore, its neuroprotective effect in a model of Parkinson’s disease in rat was evaluated.Methods: ...

Major brands of cocoa powder products present in the Spanish market were analyzed for monomeric flavanols [(+)-catechin and (-)-epicatechin] and flavonols [quercetin-3-glucuronide, quercetin-3-glucoside (isoquercitrin), quercetin-3-arabinoside, and quercetin]. In addition, the influence of the manufacturing process of cocoa powder products, in particular, the alkalinization treatment ( Dutching...

introduction: a large body of experimental evidence supports a role for oxidative stress as a mediator of nerve cell death in parkinson's disease (pd). flavonoids like quercetin have been reported to prevent neuronal degeneration caused by increased oxidative burden, therefore, this study examined whether quercetin administration at a high dose would attenuate behavioral abnormalities in e...

Quercetin is a biological flavonoid, which can be found in red kidney bean at high concentration. In this study, a comparison was conducted between traditional and modern extraction methods. Sequential microwave-assisted extraction was used for isolation of quercetin from red kidney bean. The effect of several factors such as particle size of grinded kidney bean, extraction solvent, microwave p...

five flavonoid glycosides were isolated from the n-butanol soluble fraction of the ethanolic extract of rapistrum rugosum and their structures were assigned from 1h- and 13c-nmr spectra (dept) with 2d nmr as quercetin-3-o-α-l-rhamnopyranoside (1), quercetin-3-o-β-d-xyloside (2), quercetin, 3-o-α-l-arabinopyranoside,7-o-α-l-rhamnopyranoside (3), kaempferol 3-o-α-l-arabinopyranoside, 7-o-α-l-rham...

Wild-type Arabidopsis L. leaves exposed to low ultraviolet-B (UVB) conditions contained predominantly kaempferol glycosides, with low levels of quercetin glycosides. The flavonoid level doubled on treatment with UVB and an increase in the ratio of quercetin: kaempferol was observed. These results suggest that flavonols protect Arabidopsis plants from UVB damage, and indicate that the flavonoid ...