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Activities:
Tyrosinase inhibition, antioxidant, anti-inflammatory
Important Chemical Components:
The molecular formula for arbutin is C12H16O7.
Origin Classification:
β-arbutins are natural; deoxyarbutin and α-arbutins are synthetic.
Personal Care Category:
Depigmenting, sun protective
Recommended for the following Baumann Skin Types:
DRPT, DRPW, DSPT, DSPW, ORPT, ORPW, OSPT, and OSPW
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Arbutin is a natural β-D-glucopyranoside derivative of hydroquinone (HQ) found in the dry leaves of bearberry, cranberry, blueberry, wheat, and other plants.1,2 Arbutin is the primary active constituent in bearberry (Arctostaphylos uva-ursi).
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Bearberry has been used for medicinal purposes at least since the 13th century, when it was thought to have been used in Wales.3 It is official in most pharmacopoeias.3 Arbutin, specifically, has been used in traditional medicine in Japan as a skin-lightening agent and has become an alternative to HQ for such purposes in the West (Table 35-1). Cosmetic products used for the purposes of skin whitening may include α- or β-arbutins. Of these glycosylated HQs, β-arbutin is naturally found in various plants, but α-arbutin and other arbutin derivatives, such as deoxyarbutin, are synthesized by chemical and enzymatic methods.4 Approximately 50 years ago, scientists in Japan were the first to synthesize α-arbutin from the chemical reaction of penta-O-acetyl-β-D-glucopyranose and HQ.4
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This β-D-glucopyranoside is composed of a molecule of HQ bound to glucose. Similar in structure to HQ, arbutin inhibits tyrosinase and 5,6-dihydroxyindole-2-carboxylic acid (DHICA) polymerase activities at noncytotoxic concentrations, with the hydrolyzation of the glycosidic bond resulting in a significant reduction in melanin synthesis.5,6 In particular, arbutin seems to act as a reversible competitive inhibitor of tyrosinase (post-translational level).5 That is, the depigmenting mechanism of arbutin involves a reversible inhibition of melanosomal tyrosinase activity rather than suppressing the expression and production of tyrosinase.5 Tyrosinase is the rate-limiting enzyme that regulates melanin production and is a unique product of melanocytes. Therefore, agents that block tyrosinase activity, a crucial step in melanogenesis, prevent the production of the pigment melanin and are considered key cosmetic skin-whitening ingredients. In essence, arbutin is thought to inhibit tyrosinase activity and melanosome maturation.7
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Arbutin is available in oral supplements for bladder health. As the main active constituent of bearberry, which has been used in traditional medicine as a diuretic, arbutin is thought to play a role in treating ...