Product Overview

Vitamin K3 (Menadione, INCI: Menadione, 2-Methyl-1,4-naphthoquinone, CAS 58-27-5, C₁₁H₈O₂, MW 172.18 g/mol, EINECS 200-372-6) is a synthetic provitamin K — the only synthetic precursor that the body can convert to biologically active vitamin K — and the global standard for animal feed vitamin K supplementation. First synthesized in the 1940s as the first synthetic vitamin K analog, menadione is a yellow crystalline 1,4-naphthoquinone that is structurally distinct from natural vitamin K forms (K1 phylloquinone and K2 menaquinones) in that it lacks the isoprenoid (phytyl) side chain at the C3 position. This absence of the lipophilic side chain confers water solubility — a unique property among vitamin K compounds that enables aqueous formulation and uniform distribution in feed premixes, unlike fat-soluble K1/K2. In vivo, menadione functions as a provitamin: the UBIAD1 enzyme (UbiA prenyltransferase domain-containing protein 1) catalyzes the alkylation of menadione at the C3 position using geranylgeranyl pyrophosphate (GGPP) as the isoprenoid donor, converting it to menaquinone-4 (MK-4) — the biologically active form. This conversion occurs primarily in the liver but also in extrahepatic tissues (brain, kidney, pancreas). MK-4 then serves as the essential cofactor for gamma-glutamyl carboxylase (GGCX), which drives the vitamin K-dependent gamma-carboxylation of glutamic acid (Glu) residues to gamma-carboxyglutamic acid (Gla) in vitamin K-dependent proteins: prothrombin (Factor II, coagulation), Factors VII/IX/X (hemostasis), osteocalcin (bone mineralization), matrix Gla protein or MGP (vascular calcification inhibition), and Gas6 (cell growth regulation). The naphthoquinone core also mediates a distinct quinone redox cycle: one-electron reduction by cellular flavoenzymes (NADPH-cytochrome P450 reductase) generates a semiquinone radical that reduces O₂ to superoxide (O₂•⁻), regenerating the parent quinone — establishing a futile redox cycle (menadione → semiquinone radical → superoxide → menadione) that amplifies ROS production. This redox activity is the mechanistic basis for both menadione’s antimicrobial activity (oxidative damage to microbial membranes) and its hepatotoxicity at high doses (GSH depletion, mitochondrial permeability transition), which is why it is used in animal feed — where hepatic GSH capacity and MK-4 conversion efficiency are sufficient — but not recommended for human dietary supplements.

As a leading Vitamin K3 (menadione) manufacturer and bulk supplier, UPOR Biotech provides high-purity menadione and its water-soluble complexes for B2B feed premix manufacturers, animal nutrition companies, veterinary pharmaceutical producers, and research institutions worldwide. Menadione is the global standard for poultry and swine vitamin K supplementation — incorporated into virtually every commercial vitamin premix for broilers, layers, breeders, and piglets at inclusion rates of 1–8 mg/kg complete feed. The three bisulfite complexes — MSB (Menadione Sodium Bisulfite, ~50% menadione content), MPB (Menadione Pyrimidinol Bisulfite, ~45% menadione content), and MNB (Menadione Nicotinamide Bisulfite, ~43% menadione content) — each offer distinct advantages: MSB is the most cost-effective with the highest active content; MPB provides enhanced stability in high-moisture feeds; MNB delivers the added nutritional benefit of nicotinamide (niacin/vitamin B3). Important note: Vitamin K3 (menadione) is NOT recommended for human dietary supplements due to hepatotoxicity risk at high doses. For human vitamin K supplementation, Vitamin K1 (phylloquinone) or K2 (MK-7 from natto) are the preferred, safe forms. OEM and private label formulations available with flexible MOQ. Free sample for qualified buyers. Every shipment includes full documentation: COA, MSDS, HPLC chromatogram, and stability data.

Vitamin K3 vs K1 vs K2 (MK-7) — The Vitamin K Family: Why Menadione Is the Water-Soluble Provitamin for Animal Feed While K1/K2 Are the Human Forms

The vitamin K family comprises three structurally and functionally distinct forms. Vitamin K1 (Phylloquinone, C₃₁H₄₆O₂) is the natural plant-derived form (green leafy vegetables) with a phytyl (C20) side chain; fat-soluble; the primary human dietary form; safe for human supplementation at any dose. Vitamin K2 (Menaquinones, MK-n) are bacterial/fermentation-derived forms with variable isoprenoid side chains (MK-4 through MK-14); fat-soluble; MK-7 (from natto) is the preferred human supplement form due to superior bioavailability (serum half-life ~72 h vs K1 ~1.5 h) and extrahepatic tissue distribution; supports bone health (osteocalcin carboxylation) and cardiovascular health (MGP activation). Vitamin K3 (Menadione, C₁₁H₈O₂) is the synthetic form — a 1,4-naphthoquinone with no side chain, making it water-soluble (unique among vitamin K forms). Menadione is a provitamin: it requires UBIAD1-mediated in vivo alkylation at C3 to convert to active MK-4. The absence of the phytyl side chain eliminates fat-solubility, enabling aqueous feed premix formulation — the key commercial advantage for animal nutrition. K3 is the global standard for poultry/swine feed but not recommended for human supplements due to hepatotoxicity risk from quinone redox cycling (ROS generation). For human vitamin K needs: K1 for daily dietary intake, K2 (MK-7) for supplementation (bone + cardiovascular), K3 for animal feed and research only.

Technical Specifications

PropertySpecification
Product NameVitamin K3 (Menadione) — Feed Grade (≥98% HPLC) / MSB, MPB, MNB Water-Soluble Complexes
INCI NameMenadione
IUPAC Name2-Methyl-1,4-naphthoquinone; 2-Methylnaphthalene-1,4-dione
Common SynonymsMenadione; Vitamin K3; 2-Methyl-1,4-naphthoquinone; Menaphthone; 2-Methylnaphthalene-1,4-dione; Menadionum; Provitamin K; Menadione (INCI)
CAS Number58-27-5
Molecular FormulaC₁₁H₈O₂
Molecular Weight172.18 g/mol
SourceSynthetic — chemical synthesis: 2-methylnaphthalene → CrO₃/H₂SO₄ oxidation → menadione. Not naturally occurring.
Structural Class1,4-Naphthoquinone — quinonoid structure with two carbonyl groups at positions 1 and 4; methyl substituent at position 2; no isoprenoid side chain at C3 (unlike K1/K2)
Quinone IdentificationCharacteristic quinone carbonyl stretch ν(C=O) at 1660–1680 cm⁻¹ (FT-IR); UV-Vis λmax at 245 nm (π→π*, benzenoid), 262 nm (quinonoid), and 333 nm (n→π*, carbonyl) in ethanol; positive Legal test (active methylene group adjacent to quinone — red/violet with alkaline sodium nitroprusside)
Redox PotentialE°′ (menadione/semiquinone radical) ≈ −220 mV vs NHE at pH 7.0; E°′ (semiquinone/menadiol) ≈ −240 mV vs NHE. One-electron reduction potential enables redox cycling with molecular oxygen (E°′ O₂/O₂•⁻ ≈ −330 mV vs NHE)
UV-Vis λmax (Ethanol)245 nm (Band I, benzenoid π → π*), 262 nm (Band II, quinonoid), 333 nm (Band III, n → π* carbonyl); A₁%₁cm at 262 nm ≈ 1200 (for quantitative HPLC-UV assay)
AppearanceBright yellow to yellow-orange crystalline powder with characteristic quinonoid odor
Assay (Feed Grade — Pure Menadione)≥98.0% (HPLC, anhydrous basis, UV detection at 262 nm)
Assay (Research/Pharma Grade)≥99.0% (HPLC, anhydrous basis); suitable as analytical reference standard
Available FormsPure Menadione (≥98% HPLC, feed grade); Menadione Sodium Bisulfite — MSB (water-soluble complex, ~50% menadione content); Menadione Pyrimidinol Bisulfite — MPB (water-soluble complex, ~45% menadione content); Menadione Nicotinamide Bisulfite — MNB (water-soluble complex, ~43% menadione content, with supplemental niacin)
MSB — Menadione Sodium BisulfiteC₁₁H₈O₂·NaHSO₃·3H₂O; MW ~330.3 g/mol; white to pale yellow crystalline powder; freely water-soluble (>200 g/L at 25°C); menadione content ~50% w/w; most cost-effective menadione complex; global standard for poultry/swine vitamin premixes
MPB — Menadione Pyrimidinol BisulfiteMenadione-dimethylpyrimidinol bisulfite complex; white to off-white powder; water-soluble; menadione content ~45% w/w; enhanced stability in high-moisture feed formulations; preferred for extruded aquafeed and humid storage conditions
MNB — Menadione Nicotinamide BisulfiteMenadione-nicotinamide bisulfite complex; white to pale cream powder; water-soluble; menadione content ~43% w/w; supplemental niacin (vitamin B3) in the same complex; dual-action vitamin K + niacin for comprehensive premix formulation
Melting Point (Pure Menadione)105 – 108°C (literature: 105–107°C)
Solubility (Pure Menadione)Practically insoluble in water (~0.1 g/L at 25°C); soluble in ethanol (~20 g/L), acetone, benzene, chloroform, and vegetable oils; freely soluble in alkaline aqueous solutions (enolate formation at C2 methylene)
Solubility (MSB/MPB/MNB Complexes)Freely water-soluble (>200 g/L at 25°C); aqueous solutions are stable at pH 4–7; degradation accelerates above pH 8 (quinone ring opening)
Loss on Drying≤0.5% (pure menadione, 60°C vacuum); ≤3.0% (MSB trihydrate, 105°C)
Heavy Metals (Total)≤10 ppm (as Pb)
Elemental ImpuritiesPb ≤2 ppm; As ≤1 ppm; Hg ≤1 ppm; Cd ≤1 ppm; Cr (from synthesis) ≤5 ppm (ICH Q3D compliant)
Microbial LimitsTAMC ≤1000 CFU/g; TYMC ≤100 CFU/g; E. coli — Absent in 10 g; Salmonella — Absent in 25 g; Enterobacteriaceae ≤100 CFU/g (feed grade)
Residual SolventsICH Q3C Class 2/3 compliant; residual 2-methylnaphthalene ≤100 ppm (starting material limit); methanol ≤3000 ppm; acetone ≤5000 ppm
CertificationsISO 9001:2015, ISO 22000, HACCP, FDA Facility Registration (feed use), Non-GMO, Allergen-Free, BSE/TSE-Free
Storage2 – 8°C recommended for pure menadione (light- and oxygen-sensitive quinone); RT (15–25°C) acceptable for MSB/MPB/MNB complexes; tightly sealed in original container; protect from light (amber packaging) and moisture; store under inert gas (N₂ or Ar) for long-term pure menadione storage
Shelf LifePure menadione: 2 years from date of manufacture at 2–8°C; MSB/MPB/MNB complexes: 3 years from date of manufacture at 15–25°C
PackagingPure menadione: 100 g / 500 g / 1 kg amber glass or aluminum foil bags under N₂; MSB/MPB/MNB: 1 kg / 5 kg / 25 kg sealed aluminum foil bags with PE liner; 25 kg fiber drums with double PE liner

Key Benefits — Vitamin K3 (Menadione)

Water-Soluble Provitamin K — In Vivo Conversion to MK-4 via UBIAD1

Menadione is the only water-soluble vitamin K form — the absence of the phytyl side chain at C3 eliminates fat-solubility, enabling uniform aqueous premix distribution. In vivo, UBIAD1 enzyme catalyzes C3-alkylation with GGPP to produce active MK-4 (menaquinone-4) in the liver and extrahepatic tissues. This provitamin mechanism makes menadione the only synthetic precursor to active vitamin K.

Provitamin K → MK-4

Global Feed Standard — MSB/MPB/MNB Complexes for Poultry & Swine

Menadione bisulfite complexes are the global standard for animal feed vitamin K supplementation — incorporated into virtually every commercial poultry (broilers, layers, breeders) and swine vitamin premix worldwide. Three complex options: MSB (~50% menadione) for cost-effective standard premixes, MPB (~45%) for high-moisture/extruded feeds, and MNB (~43%) delivering supplemental niacin in one complex.

Feed Standard

Gla Protein Activation — Coagulation, Bone & Vascular Health

MK-4 (from menadione conversion) is the essential cofactor for GGCX-catalyzed gamma-carboxylation of Glu to Gla residues. This activates vitamin K-dependent proteins: prothrombin (Factor II) and Factors VII/IX/X for blood coagulation (prevents hemorrhagic syndrome in poultry), osteocalcin for bone mineralization, and matrix Gla protein (MGP) for vascular calcification inhibition. Essential for animal health under intensive farming conditions.

Gla Protein Cofactor

Quinone Redox Chemistry — Dual Antimicrobial Activity & Research Tool

The 1,4-naphthoquinone core undergoes one-electron redox cycling (menadione → semiquinone radical → superoxide O₂•⁻ → menadione), generating ROS that provide broad-spectrum antimicrobial activity. This mechanism also makes menadione a valuable research tool for studying oxidative stress, vitamin K-dependent carboxylation (VKORC1/GGCX), UBIAD1 enzymology, and quinone-mediated cytotoxicity pathways in cell biology and pharmacology.

Redox Active Quinone

Applications

Poultry Feed Vitamin Premixes — Broilers, Layers & Breeders

MSB/MPB/MNB at 2–8 mg/kg complete feed to prevent coccidiosis-associated hemorrhagic syndrome and support blood clotting under intensive farming stress — the single largest application for Vitamin K3 globally. Available in bulk for feed premix manufacturers.

Swine Feed — Piglet Hemorrhagic Syndrome & Sow Reproduction

Menadione complexes at 1–5 mg/kg in swine premixes to prevent hemorrhagic syndrome in piglets and support sow reproductive performance — standard inclusion in all commercial swine vitamin premixes worldwide.

Aquaculture Feed — Fish & Shrimp Intensive Farming

MPB (enhanced moisture stability) at 2–10 mg/kg in extruded aquafeed for fish and shrimp to support coagulation under intensive aquaculture conditions — the preferred menadione complex for high-humidity aquatic feed processing.

Vitamin K-Dependent Carboxylation Research — VKORC1 & GGCX Studies

High-purity menadione (≥99% research grade) as a research tool to study vitamin K-dependent gamma-carboxylation, VKORC1 (vitamin K epoxide reductase), GGCX enzymology, and structure-activity relationships of Gla protein activation in biochemistry and pharmacology.

Quinone Redox Biology — Oxidative Stress & Cytotoxicity Research

Menadione as a model quinone for studying one-electron redox cycling, ROS generation (superoxide/semiquinone), mitochondrial oxidative stress, GSH depletion mechanisms, and NQO1 (NAD(P)H:quinone oxidoreductase)-mediated two-electron detoxification pathways in cell biology.

Veterinary Pharmaceuticals — Injectable & Oral Vitamin K Formulations

Water-soluble MSB complex for veterinary injectable and oral vitamin K formulations to treat anticoagulant rodenticide poisoning, dicoumarol toxicity (sweet clover disease), and vitamin K deficiency in livestock and companion animals.

Frequently Asked Questions

Vitamin K3 (Menadione, CAS 58-27-5, 2-methyl-1,4-naphthoquinone, C₁₁H₈O₂, MW 172.18 g/mol) is a synthetic provitamin K — the only synthetic precursor that the body can convert to biologically active vitamin K. Unlike natural K1 (phylloquinone) and K2 (menaquinones), menadione lacks the isoprenoid (phytyl) side chain at C3, making it water-soluble rather than fat-soluble. In vivo, menadione undergoes UBIAD1-mediated prenylation: the UBIAD1 enzyme (UbiA prenyltransferase domain-containing protein 1) catalyzes the alkylation of menadione at the C3 position with geranylgeranyl pyrophosphate (GGPP) as the isoprenoid donor, converting it to menaquinone-4 (MK-4) — the active form of vitamin K. This conversion occurs primarily in the liver but also in extrahepatic tissues (brain, kidney, pancreas). MK-4 then serves as the essential cofactor for gamma-glutamyl carboxylase (GGCX), which drives the vitamin K-dependent gamma-carboxylation of glutamic acid (Glu) to gamma-carboxyglutamic acid (Gla) in vitamin K-dependent proteins — prothrombin (Factor II, coagulation), osteocalcin (bone mineralization), and matrix Gla protein or MGP (vascular calcification inhibition). First synthesized in the 1940s as the first synthetic vitamin K, menadione remains the global standard for animal feed vitamin K supplementation.

Menadione (as MSB/MPB/MNB complexes) is the global standard for vitamin K supplementation in poultry, swine, and aquaculture feed. Primary applications: (1) Poultry feed — prevents coccidiosis-associated hemorrhagic syndrome, supports blood clotting under stress; typical inclusion 2–8 mg/kg complete feed for broilers, layers, and breeders. (2) Swine feed — prevents hemorrhagic syndrome in piglets, supports sow reproductive performance; typical inclusion 1–5 mg/kg. (3) Aquaculture — supports coagulation in fish and shrimp under intensive farming; typical inclusion 2–10 mg/kg. MSB (Menadione Sodium Bisulfite, ~50% menadione) is the preferred form because: (a) excellent water solubility enables uniform distribution in premixes and drinking water, (b) it is the most cost-effective menadione complex with the highest active content per unit weight, (c) it has the longest history of safe use and global regulatory acceptance (FDA, EFSA), and (d) the bisulfite adduct stabilizes the reactive quinone moiety against degradation during feed processing (pelleting, extrusion). MPB (~45% menadione) offers enhanced stability in high-moisture feeds; MNB (~43% menadione) provides supplemental niacin (vitamin B3) alongside vitamin K activity — a dual-nutrient complex for comprehensive premix formulation.

The vitamin K family comprises three forms with distinct structures and use cases. Vitamin K1 (Phylloquinone, C₃₁H₄₆O₂): natural plant-derived form with a phytyl (C20) side chain; fat-soluble; found in green leafy vegetables; the primary human dietary form; safe for human supplementation at any dose. Vitamin K2 (Menaquinones, MK-n): bacterial/fermentation-derived forms with variable isoprenoid side chains (MK-4 through MK-14); fat-soluble; MK-7 (from natto) is the preferred human supplement form due to superior bioavailability (serum half-life ~72 h vs K1 ~1.5 h) and superior extrahepatic tissue distribution; supports bone (osteocalcin) and cardiovascular health (MGP). Vitamin K3 (Menadione, C₁₁H₈O₂): synthetic form with no side chain — the water-soluble provitamin that requires UBIAD1-mediated in vivo conversion to MK-4. The global standard for poultry, swine, and aquaculture feed. NOT recommended for human dietary supplements due to hepatotoxicity risk from quinone redox cycling (ROS generation, GSH depletion). The key distinction: K1 and K2 (especially MK-7) are the human forms — safe, fat-soluble, delivering vitamin K activity directly. K3/menadione is the animal feed form — the water-soluble synthetic provitamin that animals efficiently convert to MK-4. For human vitamin K supplementation, always use K1 or K2 (MK-7); for animal feed vitamin premixes, menadione (MSB/MPB/MNB) is the global standard.

Menadione’s 1,4-naphthoquinone core mediates a single redox mechanism that explains both its beneficial antimicrobial activity and its hepatotoxic potential. The quinone undergoes one-electron reduction by cellular flavoenzymes (NADPH-cytochrome P450 reductase, NADH-ubiquinone oxidoreductase) to form a semiquinone radical intermediate. This semiquinone radical rapidly reduces molecular oxygen (O₂) to superoxide anion radical (O₂•⁻), regenerating the parent quinone — establishing a futile redox cycle (menadione → semiquinone radical → superoxide → menadione) that amplifies oxidative stress with each cycle. The resulting ROS cascade (superoxide → hydrogen peroxide → hydroxyl radical via Fenton/Haber-Weiss reactions) depletes glutathione (GSH), oxidizes protein thiols, and triggers lipid peroxidation. Antimicrobial activity: the same ROS generation damages bacterial and fungal membranes, DNA, and redox-sensitive enzymes — menadione is a broad-spectrum antimicrobial agent effective in feed preservation and against pathogenic microorganisms. Hepatotoxicity at high doses: when systemic menadione levels exceed hepatic GSH and NQO1 (NAD(P)H:quinone oxidoreductase) detoxification capacity, ROS overwhelm antioxidant defenses, triggering mitochondrial permeability transition (MPT), cytochrome c release, and hepatocyte apoptosis. Animals (poultry, swine) have sufficient hepatic GSH and MK-4 conversion capacity to safely utilize feed-grade menadione at recommended inclusion rates. For human vitamin K needs, K1 and K2 (MK-7) deliver vitamin K activity without the quinone redox liability — they contain the naphthoquinone core but their long phytyl/isoprenoid side chains alter redox potential and subcellular partitioning relative to menadione, reducing ROS generation.

Every shipment of UPOR Biotech Vitamin K3 (Menadione) includes: COA (HPLC purity ≥98.0% feed grade or ≥99.0% research grade, menadione content verification per complex — MSB ~50%, MPB ~45%, MNB ~43%, full impurity profile including 2-methyl-1,4-naphthoquinone related substances, heavy metals ≤10 ppm with Pb ≤2 ppm / As ≤1 ppm / Hg ≤1 ppm / Cd ≤1 ppm / Cr ≤5 ppm, residual solvents per ICH Q3C, microbial panel with Salmonella — Absent in 25 g and E. coli — Absent in 10 g), MSDS, HPLC Chromatogram (signed and dated, UV detection at 262 nm), UV-Vis Spectrum (λmax verification at 245/262/333 nm), FT-IR Spectrum (carbonyl stretch verification at 1660–1680 cm⁻¹), Certificate of Origin, ISO 9001:2015 Certificate, ISO 22000 Certificate, HACCP Certificate, FDA Facility Registration (feed use), Non-GMO Statement, Allergen Statement, BSE/TSE-Free Statement, Stability Data (25°C/60%RH real-time and 40°C/75%RH accelerated for MSB/MPB/MNB; 5°C long-term for pure menadione), and Complete Lot Traceability from 2-methylnaphthalene starting material to finished product. Free sample available for qualified B2B buyers. MOQ: 1 kg (pure menadione), 5 kg (MSB/MPB/MNB complexes). All documents provided in English. Additional regulatory support documentation for feed premix registrations and FAMI-QS compliance available upon request.