抄録
1. It was confirmed that thiaminase and thermostable factor existed in “Shiitake”, Lentinus edodes (Berg.) Sing. by chemical and microbiological methods. 2. The optimum pH of the enzyme was 6.5, and the optimum temperature 20°. It was inactivated by heating at 45° for 10 minutes. Organic bases such as pyridine, aniline, quinoline and P-aminobenzoic acid activated the activity, as was the case with thiaminase I. Pyrichrome was produced by ferricyanide oxidation in the presence of pyridine. 3. The thermostable factor was active at pH 6 or above, and at 60° or above. 4. The enzyme activity in the fungus was greatest in the gillus, followed by the stipe and the pileus. 5. The content of thiamine in the fungus was greatest in the gillus, followed by the pileus, and the stipe, and about 70% of the vitamin was in the esterified form.
