Abstract
It was demonstrated that thiaminase and thermostable factor existed in the fruit body of Lentinus edodes. The prescence of thiaminase in L. edodes was confirmed by chemical and microbiological assay method. The optimum pH of the enzyme was 6.5,and its optimum temperature 20℃. It was inactivated at 45℃ in 10 minutes. The organic bases such as pyridine, aniline, quinoline and p-aminobenzoic acid acted as activators, as in the case of thiaminase I. L. edodes contains not only thiaminase, but also thermostable thiamine-decomposing factor. The activity of the latter was found at pH greater than 6.0 and at 60℃ or more. The enzyme activity in L. edodes was most potent in the gillus, less in the stipe and the pileus. Thiamine was found to contain mostly in the gillus, followed by the pileus and slightly in the stipe. Of the total thiamine, the ester form was about 70 percent.
