Xanthine oxidase inhibitors from the flowers of Chrysanthemum sinense.

Institute of Natural Medicine, Toyama Medical and Pharmaceutical University, Toyama, Japan.
Planta Medica (Impact Factor: 2.35). 02/2006; 72(1):46-51. DOI: 10.1055/s-2005-873181
Source: PubMed

ABSTRACT From the MeOH extract of the flowers of Chrysanthemum sinense, a new flavone glucoside, acacetin 7- O-(3- O-acetyl- beta- D-glucopyranoside), has been isolated together with 27 known compounds including flavonoids, caffeoylquinic acid derivatives, phenolics, and a monoterpenoid glucoside. Their structures were elucidated on the basis of spectroscopic data. Compounds and displayed significant xanthine oxidase inhibitory activity in a concentration-dependent manner, and compounds and showed more potent inhibitory activity, with IC50 values ranging from 0.13 to 2.31 microM, than that of a positive control allopurinol (IC50=2.50 microM). The kinetic study indicated that and displayed competitive-type inhibition like that of allopurinol, while displayed a mixed-type inhibition.

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