抄録
In previous paper, the authors reported the chemical synthesis of vitamin D_2-sulfate and its properties and confirmed that the vitamin D_2-sulfate isolated from rabbit urine, supplemented with vitamin D_2 was coincided with the synthetic one. Afterwards, further investigations have been continued in our laboratories in regard to the biogenesis of the compound. The abilities of vitamin D_2-sulfate biogenesis were examined with various organs of rat and it was found that vitamin D_2-sulfokinase is distributed in stomach, colon and small intestine, especially in liver. The crude enzymic solution was prepared from rat liver homogenate by the salting out with ammonium sulfate. The formation of vitamin D_2-sulfate by the enzymic solution from vitamin D_2 and K_2SO_4 was recognized by Al_2O_3-impregnated paper- and thin-layer chromatographies and it was confirmed by the use of K_2^<35>SO_4. The maximum biogenesis was recognized at the two hours incubation with 0.04 μmole per 0.1ml of vitamin D.
