Safety assessment of menaquinone-7 for use in human nutrition.

Vitamin K occurs widely in foods and has been shown to have a beneficial effect on the cardiovascular system, as well as anticancer, anti-inflammatory, and antiosteoporosis properties. A previous study indicates that long-chain menaquinone-7 may be more bioavailable than vitamin K and short-chain menaquinones. In the present study, acute, subacute toxicity and genotoxicity assays were carried out to evaluate the safety of oral menaquinone-7 in albino Wistar rats. Oral administration of menaquinone-7, at a concentration of 2000 mg/kg, did not cause toxic symptoms in either male or female rats. A subacute toxicity study also proved the safety and tolerance of prolonged treatment (for 90 days) with menaquinone-7 in rats, as evidenced by biochemical, hematological, and urine parameters as well as by histopathological analysis. Genotoxicity and mutagenicity studies were performed by comet, micronucleus, and Ames tests on Salmonella typhimurium strains, which showed cellular safety and nonmutagenicity of menaquinone-7. The results indicate the safety of menaquinone-7 for human consumption.