Purification of Periploca forrestii total flavonoids and assay for the in vitro inhibitory activity on xanthine oxidase / 国际药学研究杂志

ABSTRACT

Objective: To extract and purify total flavonoids from Periploca forrestii Schltr.(P. forrestii),and test the in vitro inhibitory activity of the total flavonoids and two flvaonoidal compounds in P. forrestii,so as to provide a reference for studies on the related medicinal substances in P. forrestii. Methods: Total flavonoids were extracted from P. forrestii and then purified by the column chromatography on macroporous resin and polyamide columns. The content of total flavonoids was determined according to the Lambert-Beer’s law. The in vitro xanthine oxidase(XOD)inhibitory ac- tivity was assayed for total flavonoids and the two flavonoidal compounds by the ultraviolet spectrophotometry. Results The purified total flavonoids had a content of more than 95%. The total flavonoids and two flavonoidal compounds all showed an inhibitory effect on XOD in vitro,with the inhibitory rate enhanced with increasing concentration. The IC50 of the total flavonoids as well as the two flavonoidal compounds,quercetin-3-O-α-L-pyranoside(QP)and quercetin-7-O-β- D-glucopyranoside(QG)were 608.9,221.2 and 261.2 μg/ml,respectively. Conclusion: The total flavonoids as well as the two flvaonoidal compounds QP and QG in P. forrestii all showed the in vitro inhibitory activity on XOD.