Inhibition of mushroom-tyrosinase by aloe extract.
Inhibition by ALOE extracts of L-dopa oxidation by mushroom-tyrosinase was examined. 2''- O-Feruloylaloesin and aloesin at concentrations of 0.4 microM showed inhibition of 27 and 30%, respectively. Lineweaver-Burk plots of the concentration of L-dopa in the absence and presence of 2''- O-feruloylaloesin, 0.4 and 0.8 microM, showed that this compound inhibits mushroom-tyrosinase noncompetitively. The K (i) value obtained was 8.5 x 10 (-5) M. 2''- O-Feruloylaloesin and aloesin contents were analyzed by a reversed-phase HPLC, and their seasonal variations were observed.
Yagi
A
A
Faculty of Pharmaceutical Sciences, Fukuyama University, Fukuyama, Hiroshima, 729-02, Japan.
Kanbara
T
T
Morinobu
N
N