Biological activities of flavonoids

Flavonoids in general are extensively metabolized by enterocyte and hepatic cell enzymes and by intestinal microflora. Therefore, it is necessary to explore the biological activity of flavonoids and their metabolites in specific tissues, because the metabolites found in the blood flow or any specific organ may differ among themselves and from... 

The biological activity of flavonoids has attracted much interest in the part twenty years and a few compounds of this class have been shown to have AChEI effects. The flavanone naringenin (74) from Citrus junos (Rutaceae) ameliorated scopolamine-induced amnesia in mice, which may be related to an antiAChE effect, since naringenin was shown to inhibit AChE in vitro dose dependently. A recent theoretical study has shown that flavonoids and xanthones exhibit polyvalent effects such as antioxidant, amyloid reduction and cholinesterase inhibition, which made them interesting candidates for further studies. 

Karton, Y. et al.. Synthesis and biological activities of flavonoid derivatives as adenosine receptor antagonists, J. Med. Chem., 39, 2293, 1996. 

It is hoped that this volume will serve as a stimulus for researchers with an interest in the field of biological activity of flavonoids and heterocycles, and also stimulate further development for novel therapeutics. 

Interpretation of the in vivo biological activity of flavonoids from in vitro data requires an understanding of their bioavailability, which includes absorption and metabolism. The bioavailability of flavonoids depends on the chemical structure and whether the molecule is conjugated. Although the apparent bioavailability of flavonoids appears to be highly variable between types of flavonoid, from the very... 

Pharmacological and biological activities of flavonoids of Scutellariae radix ... 

In addition to free radical scavenging, the biological activity of flavonoids involves their action as protein kinase inhibitors and transcriptional regulators. However, the inhibitory effects of flavonoids on DNA modulating enzymes emphasize that the use of these substances as dietary supplements may also increase the risk of disease development (Moskaug, 2001). 

Moskaug, J.O. 2001. Biological activity of flavonoids, Lipidforum Nytt/News, 61, 13. 

When discussing the biological activity of flavonoids in general, and flavanols in particular, there are some major factors to be considered bioavailabDity from food, matrix effects, absorption and metabolism in the gastrointestinal tract, tissue and cellular distribution after absorption, possible interactions and/or accumulation, which are the chemical form(s) biologically available to the cell/tissue and their potential metabolism at cellular level [3, 42, 69, 70]. 

Biological activities of flavonoids and related cinnamic acid derivatives have become well known in recent years. Many studies suggest that these polyphenols have beneficial effects on human health, due to their antioxidant capacity (7) and their ability to modulate the activity of different enzymes 2-4), interact with specMc receptors (5), exert vasodilatory effects 6) and chelate metal ions such as those of Cu and Fe (7). 

Biological Activities of Flavonoids Isolated from Chinese Herb Huang Qui Inhibition of NO and PGEi Production by Flavonoids... 

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