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.
Highly bioactive and plant-based, Quercetin is known for free radical scavenging, histamine regulation, and immune response support, making it a top choice for both preventive and therapeutic health formulations.
| Parameter | Specification |
|---|---|
| Product Name | Quercetin |
| Source | Sophora Japonica Extract |
| CAS Number | 117-39-5 |
| Appearance | Yellow Green Powder |
| Product Specification | 95%, 98% Quercetin |
| Packaging | 1kg/bag/carton or 25kg/drum/carton, customizable |
| Sample | Free Samples Available |
| Shelf Life | 24 Months (Properly Stored) |
| Storage | Store in light-resistant, tightly sealed containers. Avoid moisture, sunlight, and heat |
| Certifications | KOSHER, HALAL, HACCP, ISO22000, USDA Organic, EU Organic |
Manufactured under GMP-compliant conditions with strict quality assurance:
Xi’an Best Bio-Tech Co., Ltd. specializes in the research, development, and export of natural plant extracts. Our state-of-the-art facility in Yangling, China, is GMP-compliant and serves clients in over 60 countries.
Quercetin is used for immune support, allergy relief, antioxidant supplementation, and anti-aging skincare.
Yes — it’s a plant-based bioflavonoid derived from Sophora japonica, with a long history of safe use.
Each batch is HPLC-verified for purity and tested for contaminants, heavy metals, and microbes.
Yes — we offer OEM/ODM support, custom packaging, and purity options.
Yes — COA, MSDS, TDS, and third-party lab results are available.
We have professional medicinal planting bases in Xinjiang, Gansu, and other places. From breeding, planting, fertilizing to collecting, we strive to keep medicinal materials healthy and natural. Leading technology research and development center, complete quality management system, advanced production equipment, and scientific quality control measures constitute Best’s comprehensive R&D and production system, ensuring Best can provide customers with high-quality products, and then Promote customers to realize value and win-win development. Following the sustainable development concept of “energy saving, recycling economy, safety and health”, Best applies the concept of environmental protection and low carbon to every link from raw material planting, to production and processing, and to waste recycling. A complete circular economy system. Cultivate trust with our heart and create a win-win situation with service. Best Biotech is guided by the business philosophy of “pragmatic innovation, honesty and trustworthiness, people-oriented, mutual benefit and win-win”, and will ultimately achieve “first-class quality, first-class service, first-class reputation” in the industry. Enterprise’s unremitting efforts!
Since its establishment, adhering to the business philosophy of “pragmatic innovation, honesty and trustworthiness, people-oriented, mutual benefit and win-win”, the company is equipped with imported high performance liquid chromatograph (HPLC), UV visible spectrophotometer (UV), microbial detection laboratory, rapid moisture analyzer and other testing equipment to comprehensively control the content of products, heavy metals, trace elements, trace elements, etc Microorganism and other quality indicators continue to improve production technology, strict control of product quality, has been built more advanced technology research and development center and quality testing center. In addition, we have obtained a series of qualification certificates such as HACCP certification, ISO9001:2000 quality management system certification, food QS certification, kosher certificate exported to European and American countries, and Halal certificate to ensure high quality. High standard products. We mainly produce Stevia series, anthocyanins series, frankincense acid, curcumin and other products. Through the unremitting efforts of bester people, we have reached long-term strategic cooperation with many domestic top 500 companies, and successfully sold our products to more than 50 countries and regions.
Since the establishment of the company, we have always insisted on relying on high and new technology in research and development, and constantly introduced outstanding research and development talents in the industry. In production, we use strict product quality as a means and 100% customer satisfaction as the product inspection standard, because we have achieved With rapid development, it has become a well-known and influential enterprise in the domestic and international API and plant extract industries. The company has successively passed ISO9001: 2000 quality system certification, national GMP certification and many foreign authoritative certifications.
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