抄録
Reinvestigation was made on the unknown thiamine derivatives of free and bound forms found in beef by Bessho and Isahaya showing thiochrome reaction by adding cysteine. The experiments carried out by various extraction methods showed the presence of the unknown derivatives in beef. The amount of the derivatives, however, could not be measured by the reduction method by cysteine since a part of thiaminedisulfide added to the homogenate was reduced with the reducing agents contained naturally in beef and a part of the thiaminedisulfide seemed to be adsorbed on the precipitate during the centrifugation of the homogenate.
