Arbutin health benefit and research studies by Ray Sahelian, M.D.

Arbutin is a substance found in bearberry plant and in small amounts in other plants.

Benefit
Arubutin blocks tyrosinase activity thus preventing the formation of melanin. Theoretically it could be beneficial in the skin condition melasma.

Research studies
The effects of aloesin and arbutin on cultured melanocytes in a synergetic method
Zhonghua Zheng Xing Wai Ke Za Zhi. 2004.
Cultured melanocytes in vitro were treated with the mixture of aloesin and arbutin. The cell viability and tyrosinase activity was measured by MTT assay, utilization of L-Dopa as the substrate respectively; melanin content was measured by image analysis system. Furthermore, the effects of the mixture on melanocytes were compared with that of aloesin and arbutin. The mixture of aloesin and arbutin showed an inhibition on tyrosinase activity of human melanocytes and reduced significantly melanin content. Between the mixture and the single use of aloesin or arbutin, there is significant difference. On the other hand, the mixture has little influence on melanocytes viability and there is negative significance. The mixture of aloesin and arbutin can significantly inhibit the tyrosinase activity and melanogenesis of cultured human melanocytes. It showed the effects of aloesin and arbutin in a synergistic manner. It is worth to give farther study later.

Topical agents used in the management of hyperpigmentation.
Skin Therapy Lett. 2004.
Department of Dermatology, Howard University, Washington DC, USA
Disorders of hyperpigmentation are difficult to treat, particularly in dark-skinned individuals.The goal is to reduce the hyperpigmentation without causing undesirable hypopigmentation or irritation in the surrounding normally pigmented skin. The psychosocial impact caused by these disorders must be considered. Although there are many effective therapeutic modalities available, there are potentially significant side-effects associated with treatment. The most commonly used treatment is topical hydroquinone. There are other phenolic agents, such as N-acetyl-4-cystaminylphenol (NCAP), that are currently being studied and developed. The non-phenolic agents, which include tretinoin, adapalene, topical corticosteroids, azelaic acid, arbutin, kojic acid, and licorice extract, are also used for hyperpigmentation disorders.

Structural criteria for depigmenting mechanism of arbutin.
Phytother Res. 2004. Hori I, Nihei K, Kubo I.
Department of Environmental Science, Policy and Management, University of California, Berkeley, CA, USA.
Arbutin, hydroquinone-O-beta-D-glucopyranoside (1) was found to inhibit the oxidation of l-tyrosine (monophenolase activity) catalyzed by mushroom tyrosinase. However, arbutin itself was oxidized as a monophenol substrate at an extremely slow rate, and this oxidation was accelerated as soon as catalytic amounts (0.01 mM) of l-3,4-dihydroxyphenylalanine (L-DOPA) became available as a cofactor. The result observed was supported by monitoring oxygen consumption. The depigmenting mechanism of arbutin previously reported is supportable if a cofactor is not available in the melanocytes. The combination with L-ascorbic acid is a useful application, particularly when oxygen is limited.

Inhibitory effects of alpha-arbutin on melanin synthesis in cultured human melanoma cells and a three-dimensional human skin model.
Biol Pharm Bull. 2004.
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-treated cells. The cellular tyrosinase activity of HMV-II cells also significantly decreased, while the expression of its mRNA was not affected. Melanin synthesis in a human skin model was also evaluated by the macro- and microscopic observation of its pigmentation as well as by quantitative measurements of melanin. Treatment of the human skin model with 250 microg of alpha-arbutin did not inhibit cell viability, while melanin synthesis was reduced to 40% of that in the control. These results indicate that alpha arbutin is an effective and safe ingredient for skin-lightening.

Arbutin supplement questions
Q. . I came across your study on the effects of alpha arbutin located on your website. I am currently researching ways to create my own skin cream for personal use and was wondering what concentration you would recommend for the treatment of age spots and dark discolorations. Would too high of a concentration become cytotoxic to the affected cells?

Q. I know that you have closely worked with alpha arbutin in your studies and found alpha arbutin to be very effective in the repression of melanin production. But I was wondering whether these effects of alpha arbutin were permanent? If a person stops using stops using alpha arbutin, will the hyperpigmentation return? I know that you're a very busy man, but your assitance would be greatly appreciated. Feel free to share any alpha arbutin  -related research or studies with me.
   A. I have not studied arbutin in enough detail to have a good response.

Suppliers
Fenchem has launched a new type of active compound for beautifying and whitening the skin Alpha-Arbutin(α-Arbutin, IUPAC name:4-hydroxyphenyl-α-D-glucopyranoside). Alpha-Arbutin is a new type of hydroquinone glucoside with an α-glucosyl bond. The α-glucosidic bond offers higher stability and efficacy than β-form in the related beta-Arbutin. With this product, Femchem will focus on European and US markets.As a skin-lightening of cosmetics, Alpha-Arbutin can block epidermal melanin biosynthesis by inhibiting enzymatic oxidation of Tyrosine and Dopa. Alpha-Arbutin is soluble in cold water and can be easily incorporated into cosmetic formulation either warm or cold. It is stable in the pH-range of 3.56.5. Alpha-Arbutin is a cosmetic ingredient that customers can use safely and comfortably. For the use of Alpha-Arbutin of Fenchem, you can receive not only quality assurance but also technical support in application.Fenchem also offers Beta-Arbutin, which is a cheaper alternative to Alpha-Arbutin.