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In the era of pursuing natural health, how to choose plant materials that combine scientific verification and commercial potential? Quercetin, as a globally popular flavonoid compound, has become a star ingredient in the fields of medicine, food, and skincare due to its multiple effects, such as antioxidant and anti-inflammatory.
What is Quercetin?
Quercetin is a plant-derived flavonol, belonging to the flavonoid compounds in polyphenols. It is an important medicinal component in the flavonoid compound family and also an important dietary antioxidant. It exists in plants such as fruits, vegetables, and grains. The commonly mentioned quercetin generally refers to anhydrous quercetin.
The structural formula of quercetin dihydrate(CAS 6151-25-3) contains two crystal waters, while anhydrous quercetin(CAS 117-39-5) removes the two crystal waters from the structural formula of quercetin dihydrate. Dihydroquercetin (CAS 480-18-2) is the reduced form of quercetin, which is the product of hydrogenation of the double bonds at positions 2 and 3 in the quercetin parent nucleus.
In terms of solubility, both dihydrate quercetin and anhydrous quercetin are almost insoluble in water, while dihydroquercetin with hydrogenated double bonds is soluble in water.
In terms of plant sources, because anhydrous quercetin is obtained by removing two crystal waters from dihydrate quercetin at 95-97 ℃, their sources are the same, usually the flower buds of Sophora japonica L. in the legume family. Dihydroquercetin has two sources, one of which is obtained by hydrogenating the double bonds at positions 2 and 3 in the quercetin mother nucleus. Another type is extracted from the tree segments of larch, so it is also known as taxifolin.
In appearance, quercetin dihydrate, quercetin anhydrous, and quercetin dihydro are all yellow powders, with quercetin dihydro appearing as a light yellow powder.
Quercetin VS Quercetin Dihydrate VS Dihydroquercetin (Taxifolin)
| Property | Quercetin | Quercetin Dihydrate | Dihydroquercetin (Taxifolin) |
| Crystallization Water | None | Contains 2 molecules of water | None |
| Solubility | Almost insoluble in water | Almost insoluble in water | Soluble in water |
| Melting Point | 316°C | ~93°C (decomposes upon dehydration) | 240°C |
| Activity Features | Strong antioxidant | Strong antioxidant | Slightly lower, more stable |
| Primary Sources | Plants (onion, tea leaves) | Hydrated form of Quercetin | Larch, grape seeds |
Suggested application scenarios
- Drug development: Anhydrous quercetin is suitable for high-purity formulations, while dihydroquercetin is suitable for formulations that require stability.
- Food industry: Taxifolin is commonly used as a natural preservative.
- Laboratory: Dihydrate is convenient for short-term storage, and anhydrous substances need to be stored against moisture.
Food sources of Quercetin
Quercetin is found in various foods, including vegetables such as onions, broccoli, asparagus, scallions, green peppers, tomatoes, and red lettuce, and fruits such as apples, strawberries, grapes, blueberries, cranberries, and blackcurrants.
It also exists in medicinal plants, including Ginkgo biloba, Forsythia suspensa, and ginseng, as well as many seeds, nuts, flowers, bark, and leaves. Green tea and wine are also considered rich dietary sources.
The benefits of Quercetin
1. Antioxidant
It can neutralize free radicals (the “bad molecules” that cause aging and disease), protect cells from damage, delay aging, and has antioxidant capacity 50 times that of vitamin E and 20 times that of vitamin C.
2. Anti-inflammatory effect
It can inhibit the production of inflammation in the body, repair damaged tissues and cells, and promote the continuous production of new cells, reducing the occurrence of inflammation.
3. Protect blood vessels and the heart
It can directly act on endothelial cells of blood vessels, helping to relax blood vessels and make blood flow smoother, thereby reducing blood pressure. It can reduce platelet aggregation, prevent thrombosis, and reduce the risk of atherosclerosis. It can also inhibit myocardial cell hypertrophy, dilate coronary arteries, increase cardiac blood flow, and alleviate angina symptoms, which is particularly effective for patients with coronary heart disease.
4 . Antitumor activity
It can prevent cancer cells from dividing and proliferating in the body, preventing them from replicating and dividing DNA. And cut off the vascular nutrition supply around cancer cells, inhibit vascular endothelial growth factor (VEGF), prevent the formation of new blood vessels around the tumor, and have a certain inhibitory effect on tumor growth
5. Reduce blood sugar and blood pressure
It can inhibit platelet aggregation in blood vessels, reduce thrombus formation, and maintain vascular elasticity. Delaying the breakdown of carbohydrates, thereby reducing glucose absorption, promoting insulin secretion, and lowering blood pressure and blood sugar.
Quercetin side effects
It is obtained from natural foods and is usually safe. If it is a supplement, be sure to pay attention to the dosage. Excessive intake can lead to stomach acid, joint inflammation, and liver damage, so try to use it under the guidance of a doctor.
Prohibited population for use:
- Pregnant and lactating women
- Children
- Liver and kidney function damage
- Allergic
Common side-effects:
- Headache (oral use)
- Numbness and tingling (oral use)
- Shortness of breath (intravenous use)
- Nausea and vomiting (intravenous use)
- Kidney damage (intravenous use greater than 945 mg/m2)
Where to buy Quercetin?
Runtai Chemical is a professional and reliable Chinese manufacturer of Quercetin with higher purity and lower price for 15 years. If you are interested in our product, feel free to contact us for free samples!
