Abstract
Desthiothiamine was assumed to be a keto-compound (I), corresponding to the thioketoform of thiamine (II), because both desthiothiamine and thiamine can be converted to the oxime (III) by the reaction with hydroxylamine or to imidazolethiamine (IV) by the reaction with ammonia. (I) was shown to be inhibitory to the growth of Lactobacillus fermenti 36 and Kloeckera apiculata. The inhibition by (I) could be reversed in the presence of thiamine. The growth of Saccharomyces carlsbergensis was not inhibited by (I) at the presence of pyridoxine. At the absence of pyridoxine, it was rather stimulated at the concentration between 10^<-5> and 10^<-2> M/4 of (I), whereas the growth was inhibited in either lower or higher concentration than the range : 10^<-5>-10^<-2>M/4.
