What is Quercetin?

Quercetin is a common plant secondary metabolite, chemically named 3,3′,4′,5,7-pentahydroxyflavone. It typically appears as a yellow crystalline powder that is practically insoluble in water at room temperature, but soluble in organic solvents such as ethanol and dimethyl sulfoxide (DMSO). Quercetin exhibits strong antioxidant activity, capable of stabilizing free radicals and protecting cells from oxidative damage.

Quercetin can be obtained either through extraction from plant sources or via synthetic methods. The most common method involves extraction from plants using hot ethanol, solvent extraction, or liquid–liquid partitioning techniques. Among plant sources, the bark of the Chinese parasol tree (Firmiana simplex) is frequently used, though quercetin can also be extracted from many fruits, vegetables, and medicinal herbs, including onions, apples, tea leaves, and Ginkgo biloba.

In addition to extraction, quercetin can also be chemically synthesized or biosynthesized using engineered microbial systems—approaches that are increasingly studied for scalable production.

Quercetin is generally considered a safe compound with low toxicity. However, excessive intake may lead to side effects such as gastrointestinal discomfort, nausea, and vomiting. Pregnant and breastfeeding women are advised to use quercetin with caution, and ideally under medical supervision.

Due to its anti-inflammatory, antiviral, anticancer, and cardiovascular protective properties, quercetin is widely studied in pharmacology and nutrition science, and is increasingly incorporated into dietary supplements, cosmetics, and functional foods.

Key Features

● Plant-derived quercetin flavonoid

● 95%–98% purity guaranteed by HPLC testing

● Natural antioxidant, anti-inflammatory, and antiviral support

● Ideal for use in capsules, tablets, beverages, and skincare

● Available in bulk with consistent quality

Applications

Primary Uses

• Dietary Supplements (capsules, softgels, powders)
• Immune Health and Allergy Formulas
• Functional Foods & Beverages
• Cosmetic Antioxidant Additive
• Sports Nutrition and Recovery Blends

Specific Formulation Ideas

• Immune defense capsules (with Zinc and Vitamin C)
• Antioxidant tea powders and beverages
• Skin brightening creams or anti-aging serums
• Anti-allergy and antihistamine oral formulas

Recommended Dosage

• Oral: 250–1000 mg/day (depending on formulation)
• Topical: 0.1%–1% in skincare preparations

Ingredient Compatibility

• Vitamin C
• Zinc
• Bromelain
• Resveratrol
• Curcumin

Frequently Asked Questions (FAQ)

1. What is Quercetin used for?

Quercetin is used for immune support, allergy relief, antioxidant supplementation, and anti-aging skincare.

2. Is it safe and natural?

Yes — it’s a plant-based bioflavonoid derived from Sophora japonica, with a long history of safe use.

3. How is it tested?

Each batch is HPLC-verified for purity and tested for contaminants, heavy metals, and microbes.

4. Can I get custom specifications?

Yes — we offer OEM/ODM support, custom packaging, and purity options.

5. Do you provide documentation?

Yes — COA, MSDS, TDS, and third-party lab results are available.