Quercetin is a flavonoid compound found in a number of medicinal plants that are often prescribed in Chinese clinics for the treatment of cardiovascular diseases. The present study investigated the effects of quercetin on chronic cerebral ischemia in rats produced through bilateral occlusion of the carotid arteries. Treatment of quercetin (5 mg/kg i.p. for 14 days) was found to improve the perf...

Major antioxidants of aqueous ethanol extract from Lady's Finger (Hibiscus esculentus Linn) were systematically investigated in this study. Firstly, high-performance liquid chromatography (HPLC) was applied to identify antioxidant peaks in a sample by spiking the sample extract with 2,2'-azino-bis-(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) free radical, which was prepared from manganese di...

Most flavonoids exist as sugar conjugates. Naturally occurring flavonoid sugar conjugates include glucose, galactose, glucuronide, rhamnose, xylose, and arabinose. These flavonoid glycosides have diverse physiological activities, depending on the type of sugar attached. To synthesize an unnatural flavonoid glycoside, Actinobacillus actinomycetemcomitans gene tll (encoding dTDP-6-deoxy-L-lyxo-4-...

Acacia confusa is traditionally used as a medicinal plant in Taiwan. In this study, phytochemicals and antioxidant activities of extracts from flowers of A. confusa were investigated for the first time. In addition, a rapid screening method, online RP-HPLC-DPPH system, for individual antioxidants in complex matrices was developed. Accordingly, six antioxidants including gallic acid ( 1), myrice...

The squamous cell carcinomas of the head and neck (SCCHNs) with aberrant epidermal growth factor receptor (EGFR) signaling are often associated with poor prognosis and low survival. Therefore, efficient inhibition of the EGFR signaling could intervene with the development of malignancy. Quercetin appears to be antitumorigenesis, but the underlying mechanism remains unclear in oral cancer. Fork-...

INTRODUCTION Due to frequent diagnosis of ovarian cancer at an advanced clinical stage, in most cases surgical debulking is followed by chemotherapy. The principal cause of therapeutic failure involves incomplete surgery and resistance of neoplastic cells to chemotherapy. A search continues for substances which would overcome resistance to treatment and, as a result, would increase efficacy of ...

The purpose of this study was to analyze the protective action of natural flavonoid to the reactive oxygen stress on the Band 3 protein by ektacytometry and computational docking technology. For this, quercetin, a major active ingredient of the plum and onions were used as ligand for molecular interaction. The 3D crystallographic structure of molecular target Band 3 was obtained from PDB databa...

Quercetin and 2-Methoxyestradiol (2-ME) are promising anti-cancer substances. Our previous in vitro study showed that quercetin synergized with 2-Methoxyestradiol exhibiting increased antiproliferative and proapoptotic activity in both androgen-dependent LNCaP and androgen-independent PC-3 human prostate cancer cell lines. In the present study, we determined whether their combination could inhi...

The antimicrobial activity against fish bacterial pathogens of flavonoids (morin, morin-3-O-lyxoside, morin-3-O-arabinoside, quercetin, and quercetin-3-O-arabinoside) isolated from the leaves of Psidium guajava was evaluated. The flavonoids were shown to have bacteriostatic effect on all of the tested bacteria.