抄録
Thiothiamine is stable and unchanged by a benzoyl peroxide alcohol solution in the acidic medium but readily oxidized to thiochrome by making the mixture strongly alkaline with a sodium hydroxide solution. Thiochrome, extracted by butanol, is estimated fluorimetrically after standing the mixture for 30 minutes and its formation is more quantitative compared to the BrCN-method. Perbenzoic or peracetic acid also oxidizes thiothiamine instantly to thiochrome in its alkaline solution, while hydrogen peroxide or perboric acid converts thiothiamine into thiochrome very poorly. Thiamine is indifferent on this benzoyl peroxide-NaOH method. Benzoyl peroxide in its alkaline solution yields perbenzoic acid and transforms thiothiamine into thiochrome quantitatively but rather slowly ; standing for more than 20 minutes or warming for 5 minutes at 50℃ is necessary for the analytical procedure.
