[CAS NO. 53936-56-4]  Deoxyarbutin

DeoxyArbutin demonstrates effective inhibition of mushroom tyrosinase in vitro with a Ki that is 10-fold lower that hydroquinone (HQ) and 350-fold lower than arbutin. DeoxyArbutin exhibits toxicity in darkly (higher tyrosinase activity) and lightly (lower tyrosinase activity) pigmented melanocytes with IC50 of 57.5 μM and 104.7 μM. DeoxyArbutin (100 μM) dose-dependently inhibits tyrosine hydroxylase activity in lysate from untreated, darkly pigmented melanocytes. DeoxyArbutin (100 μM) inhibits tyrosine hydroxylase activity of mushroom tyrosinase in a dose-dependent manner. DeoxyArbutin inhibits tyrosine hydroxylase activity of mushroom tyrosinase with IC50 of 17.5 μM and Ki of 21.6 μM. Water increases the decomposition of DeoxyArbutin in the formulations and the polyol-in-silicone, oil-based, anhydrous emulsion system provides a relatively stable surrounding for the DeoxyArbutin that delays its degradation at 25 ℃ and 45 ℃. DeoxyArbutin inhibits melanin synthesis in intact melanocytes in a dose-dependent manner. DeoxyArbutin exhibits dose-dependent reductions in melanocyte cell number, primarily due to inhibition of proliferation rather than initiation of apoptosis. DeoxyArbutin increases minimal amounts of reactive oxygen species (ROS) with subsequently induced expression of the endogenous antioxidant catalase in treated melanocytes.