Thiamine Derivatives of Disulfide Type. II. The Formation of Thiamine from the Disulfide Derivatives in Rat Intestine in Vitro

Abstract

The formation of thiamine from disulfide derivatives, i.e., thiamine tetrahydrofurfuryl disulfide, thiamine disulfide, thiamine benzyl disulfide, and thiamine propyl disulfide, was examined by rat intestine using a modified Wiseman-Smyth's apparatus. From the results obtained the following conclusions were drawn. 1) The rate of thiamine formation followed first order kinetics, and the derivatives with the larger rate constant had the larger partition coefficient for an organic solvent. It would mean that the interaction between lipophilic gut wall and the disulfide derivatives was the one of the important factor for the conversion. 2) The temperature effect on the conversion was examined between 27° and 47°. The contribution of chemical reaction and diffusion process was concluded from the apparent activation energy obtained. 3) Since the reduction was observed at both sides of intestine, the reaction mechanism would not relate directly to the absorption site of intestine but the general biological phenomenon which might be observed in other animal tissues.