The inhibitory effects of α-arbutin, β-arbutin, and kojic acid on melanogenesis, tyrosinase activity, and tyrosinase protein expression in mouse melanoma cells (B16-4A5) and human melanoma cells (HMV‐II) were directly compared. β-Arbutin showed a stronger inhibitory effect on melanogenesis and tyrosinase expression in B16-4A5 cells than α-arbutin and kojic acid. Kojic acid showed a stronger inh...

The effects of 4-hydroxyphenyl alpha-glucopyranoside (alpha-arbutin) and 4-hydroxyphenyl beta-glucopyranoside (arbutin) on the activity of tyrosinase from human malignant melanoma cells were examined. The inhibitory effect of alpha-arbutin on human tyrosinase was stronger than that of arbutin. The K(i) value for alpha-arbutin was calculated to be 1/20 that for arbutin. We then synthesized arbut...

BACKGROUND Cyclosporine A (CsA) is a potent immunosuppressant drug with therapeutic and toxic actions. The use of CsA is limited by its toxicity. Several researchers had proposed that oxidative stress could play an important role in CsA-induced toxicity. Arbutin has recently been shown to possess antioxidative and free radical scavenging abilities. The present study was designed to investigate ...

We assessed the effects of arbutin on the pigmentation of cultured normal human melanocytes. As indicated by a cell-blotting assay, arbutin at concentrations in the range of 0.5-8 mM increased the pigmentation of the cultured melanocytes, while kojic acid at concentrations in the range of 0.5-4 mM decreased the pigmentation. The pigmentation-augmenting effect of arbutin was further confirmed by...

Arbutin, a naturally occurring beta-D-glucopyranoside of hydroquinone, is effective in the topical treatment of various cutaneous hyperpigmentations characterized by hyperactive melanocyte function. We examined the mechanism of its depigmenting action in human melanocyte cultures. Arbutin inhibited the tyrosinase activity of cultured human melanocytes at noncytotoxic concentrations. It did not ...

Arbutin has antioxidative properties with potential benefits in many diseases. In this study, the cytoprotective and antioxidant effects of arbutin against t-BPH induced oxidative stress in Hep G2 cells were evaluated. HepG2 cells were cultured in 24-well plates (2.5×10 cells in 1 ml RPMI-1640 + 10% FBS+1% Pen. 5 Strep). Arbutin at different concentrations (0, 50, 100 and 150 μM) were added int...

Acyl arbutin was synthesized through the condensation of arbutin with a saturated fatty acid (C6-18) by the immobilized lipase in a batch reaction. The conversion at 10 and 20 g/l-solvent of immobilized lipase reached 45% over 2 d, but the initial reaction rate per amount of immobilized lipase decreased at 20 g/l-solvent. The radical scavenging activity of acyl arbutin in an ethanol solution wa...

The effects of α-arbutin on the monophenolase and diphenolase activities of mushroom tyrosinase were investigated. The results showed that α-arbutin inhibited monophenolase activity but it activated diphenolase activity. For monophenolase activity, IC50 value was 4.5 mmol · L(-1) and 4.18 mmol · L(-1) of α-arbutin could extend the lag time from 40.5 s to 167.3 s. Alpha- arbutin is proposed to b...

The phenolic glycoside arbutin and its metabolite with uroantiseptic activity hydroquinone occur naturally in the leaves of various medicinal plants and spices. In this study, an extraction procedure coupled with gas chromatography-mass spectrometry (GC-MS) was developed to determine arbutin and hydroquinone content in strawberry tree (Arbutus unedo L., Ericaceae) leaves. The method showed good...

We studied the inhibitory effects of 4-hydroxyphenyl alpha-glucopyranoside (alpha-arbutin) on melanogenesis in cultured human melanoma cells, HMV-II, and in a three-dimensional cultured human skin model. alpha-Arbutin showed no inhibitory effect on HMV-II cell growth at a concentration below 1.0 mM. Melanin synthesis in cells treated with alpha-arbutin at 0.5 mM decreased to 76% of that in non-...