The crude liver extract of rabbit had the hydrolyzing activity for ascorbate 2-sulfate (AsS) and gave inorganic sulfate with L-ascorbic acid (AsA). The optimum pH of this crude enzyme was 4.0 (sodium acetate buffer). The extracts from some organs of guinea pig and trout liver also had the hydrolyzing activity. When the enzyme activity in the livers of these animals were compared, those of the rabbit and the guinea pig were higher than that of the trout. Among the liver, adrenals, kidney, spleen and intestine of the guinea pig, the adrenals gave the highest specific activity, which was about 30 times higher than that of the liver. The purification of the crude enzyme from the rabbit liver was carried out using by ammonium sulfate or aceton precipitation method. The precipitate under 40% saturation of ammonium sulfate showed a specific activity about 4 times higher than that of the crude extract. On the other hand, the activity of the fraction from 40 to 50% concentration of aceton was only about 2 times higher than that of the crude extract.

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To clarify the interrelationships of thiamine and mineral metabolism in magnesium and calcium deficient rats, male Wistar rats were divided into four groups. Group 1 was given a calcium and magnesium deficient diet, group 2 a calcium deficient and magnesium sufficient diet, group 3 a calcium sufficient and magnesium deficient diet and a calcium and magnesium sufficient diet was given to the group 4. These dietary regimens were performed for 4 weeks. Magnesium levels in telencephalon, brainstem, spinal cord and serum decreased in magnesium deficient groups (groups 1 and 3). However, no significant change was observed in magnesium levels in heart, liver, kidney and sciatic nerve among the groups. Calcium levels in telencephalon, brainstem, spinal cord and serum decreased in calcium deficient and magnesium sufficient group (group 2) and calcium levels in serum and kidney increased in calcium sufficient and magnesium deficient group (group 3). In calcium and magnesium deficient rats (group 1), calcium levels decreased in telencephalon, brainstem and spinal cord and increased in serum and kidney. Thiamine levels decreased in telencephalon, brainstem, spinal cord, sciatic nerve and heart in calcium deficient groups (groups 1 and 2) and on the other hand, in magnesium deficient groups (groups 1 and 3) thiamine levels decreased in liver, kidney and blood.

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