Overview
Vitamin K2 (menaquinone) is a group of fat-soluble vitamers essential for calcium metabolism and blood coagulation. Unlike vitamin K1 (phylloquinone) found in leafy greens, K2 is primarily synthesized by bacteria and exists in multiple forms (MK-4 to MK-13) based on isoprenoid side-chain length. The MK-7 subtype, produced by Bacillus subtilis during natto fermentation, has superior bioavailability with a 72-hour half-life compared to MK-4's 2-3 hours. Industrial production predominantly uses bacterial fermentation, with emerging synthetic routes for specific MK-n variants. As a cofactor for γ-glutamyl carboxylase, K2 activates osteocalcin and matrix Gla proteins—critical for bone mineralization and vascular health. Regulatory status varies by region, with EFSA and FDA approving specific health claims for bone and cardiovascular benefits.
Physical and Chemical Properties
Vitamin K2 exhibits characteristic UV absorption at 248-249 nm (in ethanol) due to its naphthoquinone structure. The MK-n series shows increasing lipophilicity with longer isoprenoid chains—MK-7 (C45H64O2) is more oil-soluble than MK-4. Thermal stability allows brief pasteurization (up to 100°C), but prolonged heat degrades potency, especially in alkaline environments. Crystalline forms are rare commercially; most products are oil-based suspensions or beadlets for stability. Oxidation is the primary degradation pathway, necessitating antioxidant additives like mixed tocopherols. Spectrophotometric and HPLC-UV methods (USP <581>) are standard for purity testing, with chiral separation required to distinguish natural (trans) from synthetic (cis) isomers.
Main Applications
In nutraceuticals, MK-7 dominates the market for osteoporosis prevention, with clinical doses of 90-180 mcg/day showing 50-60% reduction in vertebral fractures. Combined with vitamin D3, it enhances osteocalcin carboxylation by 70-80%. Emerging applications include cardiovascular supplements (200 mcg/day MK-7 reduces arterial stiffness by 12% in 3 years) and sports nutrition for bone density maintenance. Pharmaceutical formulations use K2 in chewable tablets, softgels, and emulsions. Food fortification targets dairy alternatives and fermented products, though stability challenges limit bakery applications. Industrial uses include cell culture media (0.5-1 mcg/mL for stem cell differentiation) and veterinary medicine for poultry bone health.
Safety and Storage
Vitamin K2 has low acute toxicity (LD50 >5,000 mg/kg in rats) but may interact with warfarin by bypassing its anticoagulant effect. The EFSA set an upper limit of 1 mg/day for MK-4. Allergic reactions are rare but possible with fermentation-derived products—certificates should confirm absence of subtilisin and endotoxins. Bulk storage requires nitrogen-flushed amber glass or HDPE containers with oxygen scavengers. For liquid formulations, ascorbyl palmitate (0.1-0.3%) extends shelf life to 24 months at 25°C. Cold chain logistics are recommended for tropical climates, with temperature monitors verifying ≤30°C exposure during transit.
B2B Procurement Guide
When sourcing vitamin K2, prioritize suppliers with: 1) cGMP or NSF certification for fermentation facilities, 2) third-party assays confirming MK-n content (HPLC-DAD preferred), and 3) stability data under accelerated conditions (40°C/75% RH for 3 months). MK-7 from natto typically commands a 20-30% price premium over synthetic MK-4 due to superior efficacy. Contract terms should specify: minimum 95% purity (USP), residual solvent limits (hexane <50 ppm), and heavy metal testing (Pb <1 ppm). For private labeling, consider enteric-coated tablets or sunflower oil-based softgels to enhance absorption. MOQs usually start at 1 kg for R&D, with bulk discounts at 25+ kg. Sample requests should include COA and microbial testing reports.
Related Manufacturers
- 主营：大鼠醌氧化还原酶、Elisa试剂盒、检测试剂盒
- 主营：试剂盒、辅激活因子、elisa试剂盒、大鼠醌氧化还原酶1、蛋白、多肽、金标试剂盒、PCR试剂盒、抗生素、氨基酸、血清、抗体
- 主营：醌氧化还原酶1、elisa试剂盒、pcr检测试剂盒
- 主营：ELISA试剂盒、生化检测试剂盒、PCR试剂盒、大鼠ELISA试剂盒、小鼠ELISA试剂盒、兔ELISA试剂盒、鸡ELISA试剂盒
- 主营：ATCC细胞系、原代细胞、原代永生化
- 主营：大鼠醌NADH脱氢酶1、试剂盒、信号调节激酶、人转谷氨酰胺酶
- 主营：大鼠醌氧化还原酶、Elisa试剂盒、检测试剂盒
- 主营：大鼠醌氧化还原酶、elisa 试剂盒
- 主营：大鼠醌氧化还原酶1、检测试剂盒、elisa试剂盒
- 主营：Elisa试剂盒
- 主营：大鼠醌氧化还原酶1、elisa试剂盒
- 主营：elisa试剂盒、生化试剂盒、pcr检测试剂盒、醌氧化还原酶、细胞
- 主营：原代细胞、ELISA试剂盒、ELISA检测试剂盒、大鼠检测试剂盒、重组蛋白、天然蛋白、活性蛋白、基础培养基、完全培养基、抗体、标记抗体、人检测试剂盒、标记细胞、永生化细胞
- 主营：人elisa试剂盒、小鼠elisa试剂盒、其他种属elisa试剂盒、大鼠elisa试剂盒、植物elisa试剂盒、elisa试剂盒、elisa
- 主营：醌氧化还原酶1、ELISA试剂盒、PCR检测试剂盒、抗体