Sie befinden Sich nicht im Netzwerk der Universität Paderborn. Der Zugriff auf elektronische Ressourcen ist gegebenenfalls nur via VPN oder Shibboleth (DFN-AAI) möglich.
mehr Informationen...
Screening of plant extracts for human tyrosinase inhibiting effects
Ist Teil von
International journal of cosmetic science, 2012-04, Vol.34 (2), p.202-208
Ort / Verlag
Oxford, UK: Blackwell Publishing Ltd
Erscheinungsjahr
2012
Link zum Volltext
Quelle
Wiley Blackwell Single Titles
Beschreibungen/Notizen
Synopsis
Screening for tyrosinase (TYR) inhibitors potentially useful for control of skin pigmentation has been hampered by the limited availability of human TYR. To overcome this hurdle, we have established human embryonic kidney (HEK293)‐TYR cells that constitutively express human TYR. In the current study, we assayed human TYR inhibition activities of 50 plant extracts using the lysates of transformed HEK293‐TYR cells. The strongest inhibition of human TYR was shown by the extract of Vaccinium bracteatum Thunberg, followed by the extract of Morus bombycis Koidzumi. The former extract did not inhibit mushroom TYR activity whereas significant inhibition was observed with the latter extract, demonstrating the importance of using human TYR in the screening for human TYR inhibitors. Upon liquid‐liquid partitioning of the extract from V. bracteatum, the active constituents were enriched in the ethyl acetate fraction, and the subsequent preparatory thin‐layer chromatography identified p‐coumaric acid (PCA) as the main active constituent. The hypo‐pigmentation of PCA was verified in the MelanoDerm™ Skin Model. This study demonstrates that transformed HEK293‐TYR cells could expedite the discovery of human TYR‐specific inhibitors from natural sources which might be useful in the control of skin pigmentation.