Abstract
The growth of Sacch.carlsbergensis 4228 was inhibited by the presence of thiamine or some of its derivatives, but it was stimulated when the incubation time was prolonged. The adaptation of this organism was tried to 1 or 100μg of thiamine per 4ml broth and the growth of these thiamine-adapted yeasts was tested at the presence of compounds related to thiamine. Despite that thiamine diphosphate, thiamine monophosphate, benzoylthiamine monophosphate, thiamine disulfide, thiamine propyldisulfide and so on were shown to be inhibitory to the growth of normal yeast, these compounds never inhibited the growth of the thiamine-adapted yeasts. Other thiamine derivatives such as S-carbethoxythiamine, dibenzoylthiamine and O-benzoylthiamine disulfide were proved to be stimualative to the growth of the thiamine-adapted yeasts as well as of normal yeast. About antithiamine compounds, pyrithiamine, oxythiamine and imidazolethiamine inhibited the growth of both types of yeast, while deoxythiamine, 5-methylthiamine and thiamine sulfuric ester did not.
