製剤中におけるビタミンK_1の安定性 : (I) 粉末製剤におけるビタミンK_1の安定性

抄録

The stability of vitamin K_1 in powder preparations was studied by assaying the component and investigating the degradation products after 75 days storage at 45℃. Vitamin K_1 was found to be stable in organic vehicle, but unstable in inorganic one. In inorganic powders, there were detected the same decomposition products as detected when vitamin K_1 was irradiated with ultraviolet under aerobic condition, such as 2-methyl-3-(3',7',11',15'-tetramethyl-1'-hexadecenyl)-1,4-naphthoquinone-hydroxide(3'), phytone, phthiocol, polymer. Besides, there were also noticed the decomposition products, the structure of which were not determined. Percent retention of vitamin K_1 in each powders were as follow : magnesium oxide, 11% ; magnesium silicate, 19% ; magnesium carbonate, 21% ; silica gel, 23 or 52% ; aluminium silicate synthetic, 26 %.