Abstract
Diacetylthiamine (DAT) was proved to be nearly same as thiamine in stimulating the growth of Kloeckera apiculata but only one-hundredth the activity of thiamine for the growth of Lactobacillus fermenti in the broth containing cysteine. When DAT was preincubated in the broth for 24 hours, it showed one-tenth the activity of thiamine for Lactobacillus fermenti. When a suspension of Kloeckera cells in saline was inculbated for 1 hour at 30℃, a major portion of DAT was found as thiamine in the cells. DAT was not detected in the cells by either chemical estimation or bioautography of the extract of the cells. The growth response to DAT seemed to be stimulation by the thiamine quickly released from DAT.
