Vitamin K2-MK7
Compiled from published pharmacological and botanical literature. Not independently verified by Herbuno. Spotted an error or have a correction? Flag it below →
| Compound Class | Menaquinone-7; long-chain vitamin K2 with a seven-isoprenoid side chain |
| Molecular Formula / CAS | C46H64O2 · CAS 2124-57-4 |
| Source | Fermented soy or cassava — Bacillus subtilis fermentation; MK-7 is of bacterial origin |
| Standardisation | 500 ppm (0.05%) MK-7 by HPLC; all-trans isomer content is the critical parameter |
| Comparator Forms | MK-4 (synthetic or animal-derived); vitamin K1 phylloquinone; longer-chain MK-8 and MK-9 |
| Solubility / Format | Fat-soluble; ppm potency requires dilution and validated blend uniformity |
| Regulatory Note | Authorised EU health claims for vitamin K; MK-7 has an established history of use in supplements |
| Buy from Herbuno | Fermented Soy / Cassava 500 ppm |
| Origin | Processed / Sourced from India |
| MOQ | R&D 100 g / 250 g (subject to stock) · Pilot batch 1–5 kg · Bulk 10 kg, 25 kg and above |
| Lead Time | Dispatch within 72 hrs from stock · fresh-batch production (typically 50 kg+): 10 working days |
| Documentation | CoA & MSDS standard with every lot; phytosanitary on request |
Name origin: Vitamin K takes its letter from Koagulationsvitamin, the term Henrik Dam used on identifying it in Denmark in 1929 as the factor preventing haemorrhage in cholesterol-depleted chicks. The K2 menaquinones are numbered by the length of their isoprenoid side chain, so MK-7 carries seven isoprenoid units — a purely structural designation that turns out to determine almost everything about how the molecule behaves in the body.
Traditional use: The relevant tradition here is a food one, and it is genuine. Natto, soybeans fermented with Bacillus subtilis, has been eaten in Japan for centuries and is by a wide margin the richest known dietary source of MK-7. The observation that regions with high natto consumption showed differing bone and cardiovascular profiles is what drew research attention to MK-7 specifically rather than to vitamin K in general. Cassava-based fermentation is a modern adaptation of the same microbiology, developed principally to serve soy-allergen-free formulation.
Research trajectory: Vitamin K research was confined to coagulation for half a century. The discovery of vitamin K-dependent proteins outside the liver — osteocalcin in bone, matrix Gla protein in vascular tissue — opened the extrahepatic field and with it the modern bone and cardiovascular interest. Attention converged on MK-7 specifically once the pharmacokinetic differences between menaquinone chain lengths were characterised, since those differences proved far larger than anyone had assumed.
Commercial source: Commercial MK-7 is produced almost entirely by Bacillus subtilis fermentation, traditionally on a soybean substrate and increasingly on alternatives such as chickpea or cassava where soy allergen declaration is undesirable. MK-4, by contrast, is chemically synthesised. The two are not interchangeable, and as the evidence below shows, that is not a marketing distinction.
Evidence for Vitamin K2-MK7 Applications
The mechanism is specific and well characterised: vitamin K is the cofactor for γ-carboxylation of glutamate residues in vitamin K-dependent proteins, converting them to functional Gla proteins. Outside the liver this includes osteocalcin, which binds calcium in bone matrix, and matrix Gla protein, the principal endogenous inhibitor of vascular calcification. Undercarboxylated forms of these proteins are measurable and serve as functional status markers, which gives vitamin K research an unusually direct biomarker. Claim strength: High.
The MK-4 versus MK-7 comparison at nutritional doses is stark, and it is the single most important fact for anyone specifying vitamin K2. In healthy Japanese women given a single 420 µg dose with a standardised breakfast, MK-7 was well absorbed, reached maximal serum concentration at six hours and remained detectable up to 48 hours after intake — while MK-4 was not detectable in the serum of any subject at any time point. [Sato 2012] Seven days of consecutive administration at 60 µg reproduced the pattern: MK-4 supplementation did not raise serum MK-4, whereas MK-7 significantly raised serum MK-7 in all subjects. [Sato 2012 full text] Claim strength: High.
The authors' conclusion was correspondingly direct — that MK-4 present in food does not contribute to vitamin K status as measured by serum vitamin K levels, while MK-7 does and may therefore be of particular importance for extrahepatic tissues. [Sato 2012 full text] The mechanistic explanation is chain length: greater lipophilicity gives MK-7 a much longer circulating half-life and partitioning into lipoproteins that reach peripheral tissue. A caveat worth stating is that this compares nutritional doses; MK-4 is used pharmacologically at doses orders of magnitude higher, where the comparison does not apply. Claim strength: High.
The practical consequence for product design is that MK-7's long serum half-life makes once-daily dosing sufficient to maintain stable circulating concentrations, which MK-4's rapid clearance does not. This is why essentially all modern K2 supplements standardise on MK-7 and why a product specifying MK-4 at nutritional dose is difficult to defend on the serum evidence. Claim strength: Moderate.
One specification issue dominates quality in this category and is frequently glossed over: MK-7 exists as cis and trans geometric isomers, and only the all-trans form is biologically active. Fermentation-derived MK-7 is naturally all-trans, whereas synthetic routes can yield significant cis content, and a total-MK-7 assay that does not resolve the isomers will report inactive material as active. Buyers should require all-trans content specifically rather than accepting total MK-7. This is the parameter on which fermentation-derived material has a genuine and verifiable advantage. Claim strength: High.
Sourcing MK-7: A fermentation-derived vitamin K2-MK7 at 500 ppm from fermented soy or cassava is available from Herbuno, with CoA and MSDS on every lot. View Vitamin K2-MK7 500 ppm →
Dosage & Formulator Specification
Production route. MK-7 is produced by Bacillus subtilis fermentation of a soy or cassava substrate, followed by extraction and standardisation to a defined potency. The substrate choice is commercially significant rather than incidental: soy-derived material requires a soy allergen declaration in most markets, while cassava-based fermentation avoids it, which matters for allergen-free and free-from positioning. Fermentation naturally yields the all-trans isomer, which is the biologically active geometry and the principal quality advantage of the fermentation route over synthesis.
Analytical standardisation. Potency is assayed by HPLC and expressed here as 500 ppm, equivalent to 0.05% MK-7 by weight. The specification should state all-trans MK-7 content rather than total MK-7, since cis isomers are inactive and an unresolved total figure overstates the active content. Request the isomer ratio explicitly on the certificate. Substrate documentation should accompany the certificate where allergen or non-GMO status is being claimed downstream.
Regulatory and handling context. Vitamin K carries authorised EU health claims for contribution to normal blood clotting and maintenance of normal bones. MK-7 has an established history of use in food supplements in major markets, with commercial doses commonly around 45 to 180 µg/day. The critical finished-product consideration is the interaction between vitamin K and coumarin anticoagulants such as warfarin: vitamin K antagonises their action, and this warrants explicit finished-product labelling and is not a matter to leave to the consumer to infer. Store cool, dark and dry; MK-7 is light-sensitive.
Formulation behaviour. At 500 ppm, delivering a 100 µg dose requires 200 mg of material, which is a workable inclusion for tablets and capsules but still demands validated blend uniformity. MK-7 is fat-soluble and performs well in oil and softgel systems. The most common real-world stability failure in this category is interaction with mineral salts — calcium and magnesium in particular — in multi-ingredient bone formulas, where MK-7 degradation over shelf life can be substantial; if you are formulating K2 alongside minerals, generate matrix-specific stability data rather than relying on the raw material's standalone stability profile. Co-formulation with vitamin D3 is standard practice and presents no such issue.
Frequently Asked Questions — Vitamin K2-MK7
Because at nutritional doses the serum evidence is decisive. In healthy women given a single 420 microgram dose, MK-7 was well absorbed and detectable up to 48 hours, whereas MK-4 was not detectable in any subject at any time point; seven days of MK-4 at 60 micrograms per day did not raise serum MK-4, while MK-7 raised serum MK-7 in all subjects. The authors concluded that dietary MK-4 does not contribute to vitamin K status as measured by serum levels. Note this applies to nutritional doses; MK-4 is used pharmacologically at far higher doses.
MK-7 exists as cis and trans geometric isomers, and only the all-trans form is biologically active. Fermentation-derived MK-7 is naturally all-trans, while synthetic routes can produce significant cis content. Critically, a total MK-7 assay that does not resolve the isomers will count inactive cis material as active. Always specify all-trans content rather than total MK-7 and request the isomer ratio on the certificate.
It depends on your allergen positioning. Soy-fermented MK-7 requires a soy allergen declaration in most markets, while cassava-based fermentation avoids it, which matters for allergen-free and free-from product claims. The MK-7 molecule itself is identical either way, since it is produced by the same Bacillus subtilis fermentation. Request substrate documentation for your allergen and non-GMO files.
Not automatically, and this is the most common stability failure in the category. MK-7 can degrade significantly over shelf life in the presence of mineral salts, particularly calcium and magnesium, which are exactly the ingredients it is usually paired with in bone formulas. Generate stability data in your specific matrix rather than relying on the raw material's standalone profile. Co-formulation with vitamin D3 does not present the same problem.
Vitamin K antagonises coumarin anticoagulants such as warfarin, so individuals on these medications need to maintain consistent vitamin K intake and should be directed to medical advice before using a K2 supplement. This warrants explicit finished-product labelling rather than being left for the consumer to infer, and it is a labelling responsibility that sits with the brand in your target market.
Every lot ships with a Certificate of Analysis and MSDS as standard, with phytosanitary certification on request. R&D quantities are available at 100 g and 250 g subject to stock, pilot batches at 1–5 kg, and bulk at 10 kg, 25 kg and above. Stock orders dispatch within 72 hours; fresh-batch production, typically 50 kg and above, runs to about 10 working days. Material is processed and sourced in India, providing a documented alternative origin for buyers diversifying supply.
Related compounds: Vitamin D3 · Vitamin E · Betaine
Claim strength scale: High — consistent human data or established biochemistry. Moderate — supportive human data with limitations. Emerging — mechanistic or preliminary evidence only.