Abstract
Thiamine propyldisulfide (TPD) was more effective than thiamine on the growth of Lactobacillus fermenti 36 in cysteine (+)- or Na_2S_2O_3 (+)-medium, and thiamine disulfide (TDS) was as effective as thiamine. Same results were observed in the preincubated cysteine (+)- or Na_2S_2O_3 (+)- medium with TPD or TDS in which TPD or TDS was completely changed into thiamine. TPD or TDS preincubated with only cysteine was as effective as thiamine on the growth of L.fermenti. It was confirmed by using TPD-^<35>S (outer) that S-propylmercapto-L-cysteine was produced from TPD in cysteine (+)-medium, but this product had no effect on the growth of L.fermenti.
