Introduction

(6S)-5-Methyltetrahydrofolate (6S-5-MTHF), as the primary active metabolite of folate in the body, accounts for more than 98% of total folate levels in the human body. Compared to synthetic folic acid, (6S)-5-MTHF can be absorbed directly without being limited by the metabolic constraints of dihydrofolate reductase and 5,10-methylenetetrahydrofolate reductase, thereby rapidly increasing serum and red blood cell folate levels. Moreover, it does not mask the deficiency of vitamin B12, making it a significant upgrade from synthetic folic acid.

However, the stability of (6S)-5-MTHF is relatively poor, making it susceptible to degradation that can result in the formation of various impurities, such as JK12A. The potential health implications of these impurities warrant close attention and further investigation.

The Generation of JK12A

JK12A is an oxidation impurity of 5-methyltetrahydrofolate (5-MTHF), with a chemical structure described as (4-((4aS,7R)-2-amino-10-methyl-4-oxo-3,6,7,8-tetrahydro-4a,7-epiminopyrimido[4,5-b][1,4]diazepin-5(4H)-yl)benzoyl)-L-glutamic acid).

4-((4aS,7R)-2-amino-10-methyl-4-oxo-3,6,7,8-tetrahydro-4a,7-epiminopyrimido[4,5-b][1,4]diazepin-5(4H)-yl)benzoyl)-L-glutamic acid

Research has revealed that contrary to the primary oxidation products of 5-methyltetrahydrofolate (5-MTHF) described in previous literature, the actual primary degradation product of 5-MTHF is JK12A, not the 4-hydroxy-5-methyltetrahydrofolate as previously documented.

The Hazards of JK12A

Acute Toxicity: Studies have indicated that JK12A exhibits an extremely low LD50 value in mice, signifying its potent acute toxicity. At a dosage of 2000 mg/kg, all test subjects succumbed in an exceedingly short period. Despite no significant pathological changes observed in the liver and kidneys, this suggests that there may be other, as yet unidentified, toxicological targets.

Immunosuppression: JK12A has a concentration-dependent significant inhibitory effect on the proliferation of T-lymphocytes, which could further compromise the body's immune function and increase the risk of infection and disease.

Embryotoxicity: Research using the zebrafish model has shown that JK12A has a markedly negative impact on embryonic growth and cardiac development. As the concentration of exposure increases, there is a significant decrease in embryonic survival rates, a slowing of heart rate, and restricted growth in body length. The expression levels of genes related to heart development (such as has2, hand2, nkx2.5) are significantly downregulated, potentially affecting the regenerative capacity of cardiomyocytes and ultimately jeopardizing the overall development of the embryo.

These risks highlight the importance of tightly regulating the presence of impurities such as JK12A during the manufacturing and use of 6S-5-methyltetrahydrofolate.

Control of JK12A

In light of the serious risks associated with JK12A, international pharmacopoeias and regulatory bodies have established stringent limits on its concentration. Both the United States Pharmacopeia (USP) and the Joint FAO/WHO Expert Committee on Food Additives (JECFA) have capped its permissible level at 1.0%.

Magnafolate®

In the pursuit of unparalleled purity and safety in active folate supplementation, Magnafolate® has set a new benchmark for the industry. Utilizing a proprietary manufacturing process*, Magnafolate® has successfully controlled the content of JK12A to below 0.1%, significantly below the USP Pharmacopeia's limit of 1.0%. This achievement significantly enhances the product's safety profile. Moreover, Magnafolate® is backed by an array of international patent certifications and robust stability data that extends up to 48 months, solidifying its reputation as a trustworthy and high-quality choice for consumers. *Patents US10398697, JP2017-526699, AU2015311370, CN201510557500.X

In the competitive health product market of today, choosing a high-purity active folate supplement like Magnafolate®  is essential for ensuring the safety and efficacy of your products. Such a selection is instrumental in crafting a professional and dependable brand image, securing the trust and admiration of consumers.

Reference: Wang Y, Lian Z, Gu R, et al. Oxidation Product of 5-Methyltetrahydrofolate: Structure Elucidation, Synthesis, and Biological Safety Evaluation. Journal of Molecular Structure, 2024, 1316: 138909.