Quercetin

Quercetin (CAS 117-39-5), also known as quercetol, is a naturally derived flavonoid sourced primarily from plant materials such as onion skins, capers, and sophora japonica. It functions as a potent antioxidant and natural colorant across food, pharmaceutical, and cosmetic applications. In dietary supplement manufacturing, it is formulated into capsules and tablets.

These formulations often target antioxidant and immune-support positioning. Food producers use it as a natural yellow pigment and antioxidant stabilizer in beverages, confectionery coatings, and functional food products. Cosmetic and skincare formulators incorporate it into creams and serums for its UV-stabilizing and oxidative protection properties. This is particularly common in high-end anti-aging product lines.

Pharmaceutical manufacturers also use it as an active botanical ingredient in standardized herbal extracts and nutraceutical formulations. It is supplied as a fine yellow to yellow-green powder. Dihydrate forms are also available commercially for specific formulation needs. Standard grades include food-grade, USP, and pharmaceutical-grade specifications for industrial use.

Purity levels typically range from 95% to 98%+ depending on application requirements. Bulk supply is available for industrial-scale formulation, with sophora japonica-derived material being the most common source.