Planta Med 2001; 67(2): 158-161
DOI: 10.1055/s-2001-11500
Letter

© Georg Thieme Verlag Stuttgart · New York

Inhibition of Xanthine and Monoamine Oxidases by Stilbenoids from Veratrum taliense

C. X. Zhou1 , L. D. Kong1 , W. C. Ye2 , Christopher H. K. Cheng3 , R. X. Tan1,*
  • 1 Institute of Functional Biomolecules, State Key Laboratory of Pharmaceutical Biotechnology, School of Life Sciences, Nanjing University, Nanjing, People's Republic of China
  • 2 Department of Phytochemistry, China Pharmaceutical University, Nanjing, People's Republic of China
  • 3 Department of Biochemistry, The Chinese University of Hong Kong, Shatin, N. T., Hong Kong
Weitere Informationen

Publikationsverlauf

March 23, 2000

June 18, 2000

Publikationsdatum:
31. Dezember 2001 (online)

Preview

Abstract

The bioassay guided refractionation of the methanol extract of roots and rhizomes of Veratrum taliense (Liliaceae) yielded five stilbenoids: veraphenol, resveratrol, piceid, isorhapontin, and mulberroside E, all inhibiting xanthine oxidase (XO, EC 1.2.3.2.) in vitro in a dose-dependent manner with IC50 values of 11.0, 96.7, 66.1, 70.0, and 78.4 μM, respectively. Veraphenol and mulberroside E were found to be mixed XO inhibitors with the K i and K I data of the former being 32.8 and 239.3 μM, and those of latter 32.5 and 13.8 μM, respectively. However, the inhibition on the enzyme by resveratrol, isorhapontin, and piceid was shown to be competitive with their K i values of 9.7, 19.1, and 14.3 μM, respectively. Among the five stilbenoids, veraphenol and resveratrol were also revealed to inhibit competitively monoamine oxidase A (MAO, EC 1.4.3.4) with IC50 values at 38.0 and 26.6 μM, and K i data 36.4 and 47.3 μM, respectively. However, none of the stilbenoids was inhibitory on MAO B in our assay. The structure-activity relationship examination showed that glycosylation of the stilbenoids could reduce the inhibition on XO and diminish the activity against MAO A, indicating that the free phenolic hydroxy group of the compounds was most likely essential for these bioactivities.

References

Prof. Dr. R. X. Tan

Institute of Functional Biomolecules

School of Life Sciences

Nanjing University

Nanjing 210093

P. R. China

eMail: rxtan@netra.nju.edu.cn

Telefon: Tel. & Fax: +86 25 359 3201