Quercetin Dihydrate Powder — ≥95% HPLC (Cosmetic & Nutraceutical Grade) from Sophora japonica Supplier
Quercetin Dihydrate (CAS 6151-25-3, INCI: Quercetin, C₁₅H₁₀O₇·2H₂O, MW 338.27 g/mol) — a natural plant-derived flavonoid with a unique multi-mechanism bioactive profile: zinc ionophore (enhances intracellular zinc uptake → antiviral and immune support), SIRT1 activator (longevity pathway), potent Nrf2/ARE antioxidant, and senolytic activity (selectively clears senescent “zombie cells” of aging). Extracted from Sophora japonica (Japanese pagoda tree) flower buds — the botanical source with the highest natural quercetin content. Available as fine powder and 20-60 mesh granular for supplement manufacturing. ISO 9001:2015, ISO 22000, HACCP, FDA, HALAL, KOSHER, Non-GMO certified. Bulk manufacturer and wholesale supplier — premium quercetin dihydrate from UPOR Biotech.
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Quercetin Dihydrate (QUE, QCT, INCI: Quercetin, 3,3′,4′,5,7-Pentahydroxyflavone dihydrate, CAS 6151-25-3, C₁₅H₁₀O₇·2H₂O, MW 338.27 g/mol, sophoretin, meletin) is a natural flavonoid extracted from Sophora japonica (Japanese pagoda tree) flower buds — the botanical source with the highest naturally occurring quercetin content, where rutin is acid-hydrolyzed to yield the quercetin aglycone. Quercetin dihydrate operates through a unique multi-mechanism profile unmatched by any other single flavonoid: (1) Zinc ionophore — quercetin chelates zinc extracellularly and transports it across the lipophilic cell membrane, increasing intracellular zinc concentrations without relying on native zinc transporter proteins. Elevated intracellular zinc inhibits viral RNA-dependent RNA polymerase (RdRp), disrupts proteolytic processing of viral polyproteins, and enhances innate immune cell function including T cells, NK cells, and macrophages. In vitro studies demonstrate quercetin + zinc achieves 89.3% inhibition of influenza A (H1N1) after 24 hours — far exceeding additive effects. (2) SIRT1 activation — quercetin activates the NAD+-dependent deacetylase SIRT1, which deacetylates PGC-1α (mitochondrial biogenesis), FOXO transcription factors (antioxidant defense), and p53 (DNA repair), promoting longevity and cellular stress resistance. (3) Nrf2/ARE pathway — quercetin activates the master antioxidant response element, upregulating endogenous glutathione (GSH), superoxide dismutase (SOD), and catalase — providing comprehensive cellular antioxidant defense superior to direct radical scavenging alone. (4) Senolytic activity — quercetin selectively induces apoptosis in senescent cells (the “zombie cells” of aging that accumulate with age and secrete inflammatory SASP factors) by targeting PI3K/Akt, Bcl-xL, NF-κB, p16, and p21 anti-apoptotic pathways. The Dasatinib + Quercetin (D+Q) combination is the most extensively studied senolytic regimen, with multiple ongoing Phase 2 clinical trials. The dihydrate crystalline form provides superior physicochemical stability compared to anhydrous quercetin — better resistance to oxidative degradation during storage and formulation, and more consistent assay values over shelf life. The Sophora japonica source matters clinically: it yields the highest natural quercetin concentration of any botanical and provides a consistent, standardized flavonoid profile that synthetic routes cannot replicate.
As a leading quercetin dihydrate manufacturer and bulk supplier, UPOR Biotech provides high-purity quercetin dihydrate powder and granular forms for B2B nutraceutical brands, cosmeceutical companies, functional food manufacturers, contract manufacturers, and private-label formulators worldwide. Quercetin’s multi-market positioning spans nutraceuticals (zinc ionophore immune support supplements — one of the fastest-growing supplement categories), cosmeceuticals (anti-aging antioxidant serums and creams leveraging SIRT1 + senolytic mechanisms), and functional foods and beverages (microencapsulated quercetin for antioxidant fortification). The 20-60 mesh granular form is specifically engineered for supplement manufacturing — delivering superior flowability, reduced dusting, uniform particle size distribution, and consistent compression characteristics critical for high-speed tablet pressing and capsule filling operations. The global quercetin market is experiencing rapid growth driven by longevity science (senolytic and SIRT1 research advancing rapidly), immune health trends (zinc + quercetin combination products gained mainstream adoption), and expanding applications in functional foods and cosmeceuticals. OEM and private label formulations available with flexible MOQ starting at 1 kg. Free sample available for qualified B2B buyers. Every shipment includes full documentation: COA, MSDS, HPLC chromatogram, and stability data.
Quercetin Dihydrate vs Fisetin vs Resveratrol — The Flavonoid Longevity Molecule Showdown: Which Is Right for Your Formulation?
Comparing the three leading polyphenol longevity molecules reveals complementary — not competitive — mechanisms. Quercetin Dihydrate is the multi-target workhorse: zinc ionophore (unique among flavonoids — transports zinc across cell membranes for antiviral and immune support), SIRT1 activator, Nrf2/ARE antioxidant, and established senolytic in the D+Q (Dasatinib + Quercetin) combination — the most clinically studied senolytic regimen with multiple ongoing Phase 2 trials (NCT04907253 for coronary artery disease, NCT02848131 for CKD). Fisetin is the strongest standalone natural senolytic — selectively induces apoptosis in senescent cells by suppressing Bcl-2 family proteins and disrupting SCAP (senescent cell anti-apoptotic pathways). Mayo Clinic studies (Yousefzadeh et al. 2018) demonstrated fisetin extended lifespan and reduced p16-positive senescent cells in mice; currently in AFFIRM-LITE clinical trials (NCT03675724). Lower effective in vitro dose than quercetin (20–25 vs 25–40 µmol/L) — suggesting greater standalone senolytic potency — but fisetin lacks the zinc ionophore mechanism that distinguishes quercetin. Resveratrol is primarily a senomorphic (SASP suppressor) rather than a true senolytic — works mainly through SIRT1 activation and Nrf2 pathway modulation, with more indirect anti-aging effects on mitochondrial function and immunometabolism. No independent senolytic cell clearance. Strategic formulation insight: Quercetin + Fisetin is synergistic — quercetin enhances fisetin bioavailability when co-administered, combining the strongest standalone senolytic (fisetin) with the zinc ionophore + SIRT1 amplification (quercetin). Quercetin + Zinc is the definitive immune-support combination — no other flavonoid delivers this mechanism. For pure senolytic potency, fisetin leads; for multi-target mechanistic breadth (zinc ionophore + senolytic + SIRT1 + Nrf2/ARE), quercetin dihydrate is unmatched. All three share poor oral bioavailability (<10% reaches plasma), driving demand for advanced delivery systems — liposomal, phytosome, and nanoencapsulated quercetin formulations.
Technical Specifications
| Property | Specification |
|---|---|
| Product Name | Quercetin Dihydrate Powder — ≥95% HPLC (Cosmetic & Nutraceutical Grade) from Sophora japonica |
| INCI Name | Quercetin |
| Common Name / Synonyms | Quercetin Dihydrate; 3,3′,4′,5,7-Pentahydroxyflavone dihydrate; Sophoretin; Meletin; Quercetol; 2-(3,4-Dihydroxyphenyl)-3,5,7-trihydroxy-4H-chromen-4-one dihydrate; QUE; QCT |
| CAS Number (Dihydrate) | 6151-25-3 |
| CAS Number (Anhydrous) | 117-39-5 |
| Molecular Formula | C₁₅H₁₀O₇·2H₂O (dihydrate); C₁₅H₁₀O₇ (anhydrous) |
| Molecular Weight | 338.27 g/mol (dihydrate); 302.24 g/mol (anhydrous) |
| Source | Sophora japonica (Japanese pagoda tree) flower bud extract — natural plant-derived flavonoid; rutin acid-hydrolyzed to quercetin aglycone |
| Key Advantage | Multi-mechanism bioactive: zinc ionophore (intracellular zinc transport → antiviral/immune), SIRT1 activator (longevity pathway), Nrf2/ARE antioxidant, senolytic activity (selectively clears senescent cells). Dihydrate form for superior stability vs anhydrous. |
| Appearance | Yellow to greenish-yellow fine crystalline powder; granular form: 20-60 mesh free-flowing granules |
| Assay (HPLC) | ≥95.0% (anhydrous basis) — Cosmetic & Nutraceutical Grade; ≥98.0% (anhydrous basis) — Research Grade available |
| Identification | IR spectrum conforms to quercetin dihydrate reference standard; HPLC retention time matches USP Quercetin RS; UV λmax ~256 nm and ~370 nm (characteristic flavonol spectrum) |
| Loss on Drying | ≤12.0% (corresponding to dihydrate water of crystallization; 105°C to constant weight) |
| Water Content (Karl Fischer) | 9.0 – 12.0% (dihydrate stoichiometric range) |
| Residue on Ignition | ≤0.5% (sulfated ash) |
| Melting Point | >300°C (with decomposition; characteristic of flavonoids) |
| pH (0.1% Suspension) | 4.5 – 6.5 |
| Solubility | Soluble in hot ethanol (1:23), cold ethanol (1:300), methanol, ethyl acetate, glacial acetic acid, alkaline aqueous solutions, propylene glycol; practically insoluble in water, petroleum ether, benzene, chloroform |
| Particle Size (Granular) | 20-60 mesh (250–841 µm) — engineered for superior flowability and compression in supplement manufacturing |
| Heavy Metals (Total) | ≤10 ppm (as Pb) |
| Elemental Impurities | Pb ≤2 ppm; As ≤1 ppm; Hg ≤1 ppm; Cd ≤1 ppm (USP <232> / ICH Q3D compliant) |
| Microbial Limits | TAMC ≤1,000 CFU/g; TYMC ≤100 CFU/g (USP <61> / EP <2.6.12>); Pathogens (E. coli, Salmonella, S. aureus, P. aeruginosa) — Absent in 10 g (USP <62> / EP <2.6.13>) |
| Residual Solvents | USP <467> / ICH Q3C Class 3 compliant; ethanol ≤5,000 ppm |
| Recommended Usage (Nutraceutical) | 500–1,000 mg per day (oral); enhance absorption with dietary fat or piperine co-administration. Typical zinc + quercetin: 500 mg quercetin + 15–30 mg elemental zinc per serving. |
| Recommended Usage (Cosmetic) | 0.1 – 1.0% in leave-on formulations; pre-dissolve in ethanol or propylene glycol before aqueous phase incorporation. pH 4–7 optimal. |
| Grade / Standards | Cosmetic & Nutraceutical Grade (≥95% HPLC); Research Grade (≥98% HPLC) |
| Available Forms | Fine powder; 20-60 mesh granular (optimized for dry supplement manufacturing — flowability, reduced dusting, compression) |
| Certifications | ISO 9001:2015, ISO 22000, HACCP, FDA Facility Registration, HALAL, KOSHER, Non-GMO, BSE/TSE-Free |
| Packaging | 1 kg / 5 kg / 10 kg sealed aluminum foil bags with PE liner; 25 kg fiber drums with double PE liner; vacuum-sealed option available |
| Storage | 15–25°C, tightly sealed in original container, protect from light and moisture; avoid alkaline conditions |
| Shelf Life | 3 years from date of manufacture under recommended storage conditions |
Key Benefits — Quercetin Dihydrate
Zinc Ionophore — Enhanced Intracellular Zinc Uptake for Antiviral & Immune Support
Quercetin’s unique zinc ionophore mechanism chelates zinc and transports it across cell membranes, bypassing rate-limiting native transporters. Elevated intracellular zinc inhibits viral RdRp, disrupts viral polyprotein processing, and enhances T cell, NK cell, and macrophage function. In vitro: 89.3% influenza A (H1N1) inhibition with quercetin + zinc at 24 hours — the definitive immune-support flavonoid mechanism.
Zinc IonophoreSIRT1 Activation & Senolytic Activity — Longevity Pathway + Senescent Cell Clearance
Quercetin activates SIRT1 (NAD+-dependent deacetylase) — deacetylating PGC-1α for mitochondrial biogenesis, FOXO for antioxidant defense, and p53 for DNA repair. Simultaneously, quercetin is an established senolytic in the D+Q combination — selectively clearing senescent “zombie cells” via PI3K/Akt, Bcl-xL, and NF-κB pathway targeting. Multiple Phase 2 clinical trials underway.
SIRT1 + SenolyticNrf2/ARE Master Antioxidant — Endogenous Glutathione, SOD & Catalase Upregulation
Quercetin activates the Nrf2/ARE pathway — the body’s master antioxidant response element — upregulating endogenous glutathione (GSH), superoxide dismutase (SOD), and catalase. This provides comprehensive cellular antioxidant defense superior to direct radical scavenging alone. Combined with direct ROS quenching, quercetin delivers dual-layer antioxidant protection unmatched by single-mechanism antioxidants.
Nrf2/ARE AntioxidantSophora japonica Source + Dihydrate Stability — Premium Natural Quality & Formulation Reliability
Extracted from Sophora japonica flower buds — the botanical with the highest natural quercetin content. The dihydrate crystalline form provides superior physicochemical stability vs anhydrous quercetin: better resistance to oxidative degradation, more consistent assay values over shelf life, and reliable 20-60 mesh granular option for supplement manufacturing. ISO 9001, ISO 22000, HALAL, KOSHER certified.
Premium Natural QualityApplications
Nutraceutical Immune Supplements — Zinc + Quercetin Combination (500 mg + 15–30 mg Zn)
500–1,000 mg quercetin + 15–30 mg elemental zinc per serving for antiviral and immune support. The zinc ionophore mechanism amplifies intracellular zinc bioavailability — the fastest-growing immune supplement category. OEM and private label formulations available with flexible MOQ starting at 1 kg.
Anti-Aging Cosmeceuticals — SIRT1 + Senolytic Skincare (0.1–0.5% Topical)
0.1–0.5% quercetin in anti-aging serums and creams leveraging SIRT1 activation (mitochondrial biogenesis) and senolytic activity (senescent cell clearance) for comprehensive skin longevity formulations. Pre-dissolve in propylene glycol or ethanol for incorporation.
Functional Beverages — Microencapsulated Quercetin for Wellness Shots
Microencapsulated or liposomal quercetin at 100–250 mg per serving in functional beverages, wellness shots, and anti-aging elixirs. Overcomes aqueous solubility limitations while maintaining bioactivity. Growing consumer demand for “longevity beverages” with clinically supported flavonoids.
Antioxidant Serums & UV Protection — 0.1–1% Topical Formulations
Quercetin at 0.1–1% in antioxidant serums, day creams, and sunscreens. Nrf2/ARE pathway activation provides endogenous antioxidant defense against UV-induced oxidative stress and photoaging. Combine with vitamin C and vitamin E for synergistic antioxidant network effects.
Pet Supplements — Canine & Feline Joint + Immune Health (50–250 mg)
Quercetin at 50–250 mg per serving in pet supplements for antioxidant support, inflammatory modulation, and immune health in dogs and cats. Often combined with bromelain for enhanced absorption. Growing pet wellness market with demand for clinically backed natural bioactives.
Pharmaceutical Research — Senolytic Drug Development (≥98% Research Grade)
Quercetin dihydrate ≥98% HPLC (Research Grade) for senolytic drug development, D+Q combination clinical trials, and academic longevity research. Reference standard qualification available. Type II DMF support available for pharmaceutical development programs.
Frequently Asked Questions
Quercetin Dihydrate (CAS 6151-25-3, INCI: Quercetin, C₁₅H₁₀O₇·2H₂O, MW 338.27 g/mol) is a natural flavonoid extracted from Sophora japonica flower buds with a multi-target mechanism profile. (1) Zinc Ionophore — quercetin chelates zinc ions extracellularly and transports them across the lipophilic cell membrane, increasing intracellular zinc concentrations without relying solely on native zinc transporter proteins. Elevated intracellular zinc inhibits viral RNA-dependent RNA polymerase (RdRp), disrupts proteolytic processing of viral polyproteins, and enhances immune cell function including T cells, natural killer cells, and macrophages. In vitro studies demonstrate quercetin + zinc achieves up to 89.3% inhibition of influenza A (H1N1) after 24 hours. (2) SIRT1 Activation — quercetin activates SIRT1, the NAD+-dependent deacetylase that regulates longevity, mitochondrial biogenesis, and cellular stress resistance. SIRT1 deacetylates PGC-1α, FOXO transcription factors, and p53 — promoting mitochondrial function, antioxidant defense, and DNA repair. (3) Nrf2/ARE Pathway — quercetin activates the master antioxidant response element, upregulating endogenous antioxidant enzymes including glutathione (GSH), superoxide dismutase (SOD), and catalase. (4) Senolytic Activity — quercetin selectively induces apoptosis in senescent cells by targeting PI3K/Akt, Bcl-xL, NF-κB, p16, and p21 anti-apoptotic pathways. The Dasatinib + Quercetin (D+Q) combination is the most clinically studied senolytic regimen. The dihydrate crystalline form offers superior stability compared to anhydrous quercetin, with better resistance to oxidative degradation during storage and formulation. UPOR Biotech supplies both ≥95% and ≥98% HPLC grades as powder and 20-60 mesh granular.
Quercetin Dihydrate delivers four clinically significant benefit categories: (1) Immune Support & Antiviral — as a zinc ionophore, quercetin amplifies intracellular zinc availability, inhibiting viral replication (RdRp inhibition) and enhancing innate immune function. Clinical trials have evaluated quercetin + zinc combinations for respiratory viral infections with synergistic antiviral effects. (2) Anti-Aging & Longevity — SIRT1 activation promotes mitochondrial biogenesis, cellular stress resistance, and DNA repair via PGC-1α/FOXO/p53 deacetylation. The senolytic activity clears senescent “zombie cells” that accumulate with age and secrete inflammatory SASP factors. The D+Q combination is the most extensively studied senolytic regimen in clinical trials (NCT04907253, NCT02848131). (3) Potent Antioxidant Protection — Nrf2/ARE pathway activation upregulates endogenous glutathione, SOD, and catalase — providing comprehensive cellular antioxidant defense superior to direct radical scavenging alone. (4) Cosmetic & Skincare — quercetin at 0.1–1% in topical formulations provides antioxidant protection against UV-induced oxidative stress, reduces inflammation via NF-κB inhibition, and supports anti-aging through senolytic and SIRT1 mechanisms. UPOR Biotech supplies both powder and 20-60 mesh granular forms for versatile formulation across nutraceuticals and cosmeceuticals.
Nutraceutical (oral) dosage: 500–1,000 mg per day, typically divided into two doses (BID) due to ~3.5-hour half-life. Quercetin absorption is enhanced when taken with dietary fat or formulated with bioavailability enhancers such as piperine (from black pepper extract) or phytosome delivery systems. The quercetin + zinc combination is commonly formulated at 500 mg quercetin with 15–30 mg elemental zinc per serving (as zinc citrate, gluconate, or picolinate). Cosmetic (topical) usage rate: 0.1–1.0% in leave-on formulations including serums, creams, and lotions. Quercetin is practically insoluble in water — pre-dissolve in ethanol, propylene glycol, or a suitable co-solvent system before incorporation into the aqueous phase. pH stability is optimal between 4–7; avoid strongly alkaline conditions (pH >8) which accelerate oxidative degradation. The 20-60 mesh granular form is ideal for dry supplement manufacturing — providing superior flowability, reduced dusting, and consistent compression characteristics in tablet pressing and capsule filling operations. For functional beverages, use microencapsulated or liposomal quercetin to overcome aqueous solubility limitations and improve bioavailability. UPOR Biotech provides formulation guidance and technical support for all product forms. Recommended formulation synergies: quercetin + zinc (immune), quercetin + fisetin (longevity/senolytic), quercetin + vitamin C + vitamin E (antioxidant network).
Quercetin, fisetin, and resveratrol are the three leading polyphenol longevity molecules — each with distinct, complementary mechanisms. Quercetin Dihydrate (flavonol, MW 338.27): Multi-target bioactive — zinc ionophore (unique among flavonoids) + SIRT1 activator + Nrf2 inducer + established senolytic in the D+Q combination. The most clinically studied natural senolytic with multiple Phase 2 trials (NCT04907253, NCT02848131). Most effective when combined; independent zinc ionophore mechanism unique among flavonoids. Fisetin (flavonol, MW 286.2): The strongest standalone natural senolytic — selectively induces apoptosis in senescent cells by suppressing Bcl-2 family proteins and disrupting SCAP (senescent cell anti-apoptotic pathways). Mayo Clinic studies (Yousefzadeh et al. 2018) demonstrated fisetin extended lifespan and reduced p16-positive senescent cells in mice. Currently in AFFIRM-LITE clinical trials (NCT03675724). Lower effective dose than quercetin (20–25 vs 25–40 µmol/L) but lacks zinc ionophore activity. Resveratrol (stilbenoid, MW 228.2): Primarily a senomorphic (SASP suppressor via SIRT1/Nrf2), not a true senolytic. More indirect anti-aging effects through mitochondrial and metabolic modulation. The three are highly complementary — quercetin provides zinc ionophore + combination senolytic activity, fisetin delivers the strongest standalone senolytic action, and resveratrol offers metabolic/SIRT1 support. Quercetin + Fisetin is synergistic — quercetin enhances fisetin bioavailability when co-administered. For pure senolytic potency: fisetin; for multi-target mechanistic breadth (zinc ionophore + senolytic + SIRT1 + Nrf2/ARE): quercetin dihydrate is unmatched. All three share poor oral bioavailability (<10% reaches plasma), driving demand for advanced delivery systems — liposomal, phytosome, and nanoencapsulated formulations.
Every shipment includes: COA (HPLC purity ≥95.0% or ≥98.0% depending on grade, full impurity profile, heavy metals ≤10 ppm with Pb ≤2 ppm / As ≤1 ppm / Hg ≤1 ppm / Cd ≤1 ppm, residual solvents per USP <467> / ICH Q3C, microbial panel per USP <61>/<62>, loss on drying, residue on ignition, pH, water content by Karl Fischer, particle size distribution for granular grade), MSDS, HPLC Chromatogram (signed and dated), Certificate of Origin (Sophora japonica flower bud extract), BSE/TSE-Free Statement, Non-GMO Statement, Allergen Statement, HALAL Certificate, KOSHER Certificate, ISO 22000 + HACCP, ISO 9001:2015, FDA Facility Registration, Stability Data (25°C/60%RH real-time 36-month and 40°C/75%RH accelerated 6-month), Residual Solvent Declaration per ICH Q3C, Elemental Impurities Statement per USP <232> / ICH Q3D, and Complete Lot Traceability from Sophora japonica raw material to finished product. Free sample (10–50 g) available for qualified B2B buyers. MOQ: 1 kg for powder; 25 kg for granular. All documents provided in English. OEM and private label services available with flexible MOQ and custom formulation support.