Alpha - arbutin (IUPAC: 4 - Hydroxyphenyl α - D - glucopyranoside) is a premium, biosynthetic skin - brightening active ingredient widely applied in cosmetics, famous for its efficient, safe, and stable whitening performance, far outperforming β - arbutin in tyrosinase inhibition and stability. With CAS 84380-01-8, it is a glycoside compound formed by the combination of hydroquinone and glucose, naturally present in bearberry, blueberries, and cranberries, and is now mainly produced via advanced bio - enzymatic synthesis for high purity and consistent quality.
Its core mechanism is directly inhibiting tyrosinase activity—the key enzyme in melanin synthesis—without suppressing cell growth or causing cytotoxicity, and it does not produce harmful hydroquinone during metabolism. It can effectively fade chloasma, sunspots, age spots, and post - inflammatory hyperpigmentation, and also has anti - inflammatory, antibacterial, and moisturizing effects, helping to soothe irritated skin and improve overall skin health.
It has excellent compatibility with common cosmetic ingredients such as hyaluronic acid, niacinamide, and vitamin C, and is suitable for a wide range of formulations including serums, creams, masks, and spot treatments. The recommended addition level is 0.2% - 2% for facial products and ≤ 0.5% for body care products, as per SCCS safety guidelines. It is stable under pH 3.5-6.5, and storing in light - proof, sealed containers at 15-25°C can maintain its efficacy for at least 36 months.
