Planta Med 2003; 69(5): 457-459
DOI: 10.1055/s-2003-39708
Letter
© Georg Thieme Verlag Stuttgart · New York

Kinobeon A as a Potent Tyrosinase Inhibitor from Cell Culture of Safflower: In vitro Comparisons of Kinobeon A with Other Putative Inhibitors

Tsutomu Kanehira1 , Susumu Takekoshi2 , Hidetaka Nagata2 , R. Yoshiyuki Osamura2 , Takao Homma1
  • 1Department of Applied Chemistry, Tokai University Graduate School of Engineering, Hiratsuka, Kanagawa, Japan
  • 2Department of Pathology, Tokai University School of Medicine, Isehara, Kanagawa, Japan
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Publikationsverlauf

Received: September 3, 2002

Accepted: January 25, 2003

Publikationsdatum:
12. Juni 2003 (online)

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Abstract

Kinobeon A is produced from cell cultures of the medicinal plant, safflower. Mushroom tyrosinase activity was inhibited in a concentration-dependent manner when treated with kinobeon A using L-tyrosine or L-3, 4-dihydroxyphenylalannine (L-DOPA) as substrates. IC50 values were 22 μM (substrate: L-tyrosine) and 27 μM (L-DOPA). Inhibition of human tyrosinase activity also increased with increasing concentrations of kinobeon A using L-DOPA as the substrate, with an IC50 value of 2.5 μM. Kinobeon A was a more potent competitive inhibitor than kojic acid, arbutin or L-ascorbic acid for both mushroom and human tyrosinase as determined from Lineweaver-Burk plots. These results suggested that kinobeon A could be a potent natural tyrosinase inhibitor.

References

Ph D. Susumu Takekoshi

Department of Pathology

Tokai University School of Medicine

Bohseidai

Isehara

Kanagawa 259-1193

Japan

Telefon: +81-463-93-1121 ext. 2570

Fax: +81-463-91-1370

eMail: takekos@is.icc.u-tokai.ac.jp