초록 |
Melanin synthesis is controlled by a cascade of enzymatic reactions regulated at the level of tyrosinase in melanocytes and melanoma cells. In an ongoing search for new tyrosinase inhibitors from natural sources, the dried leaves of Schisandra chinensis (SCL) were extracted with 70% acetone and separated into fractions 1-3 (Fr.1-3). Fr.2 showed potent tyrosinase activities with 22.0 % inhibition concentration 1000 µg/mL compared to the positive control, albutin (24.8%). Fr.2 which showed a significant inhibition effect against tyrosinase led to the isolation and identification of three known phenoilic compounds (1-3): chlorogenic acid (1), isoquercitrin (2), quercetin (3). We investigated the changes in protein level of tyrosinase, Melanocyte Inducing Transcription Factor (MITF) by using western blotting. Fr.2 was able to significantly inhibit tyrosinase and MITF expression in protein level. |