ビタミンB_1誘導体の微生物活性 : (XIII) ThiazinothiamineならびにPseudothiamine誘導体(1)

抄録

Microbiological assay of new modified thiamine compounds of 3 thiazionthiamine derivatives (I-a, b, c, ) and pseudothiamine (II) was studied ; only pseudo-acetothiamine-O-acetate (II) was proved to have about 1/1,000 the potency of thiamine on both the assays using L.fermenti and Kl.apiculata. The compound (II) is gradually hydrolysed to thiamine in the broth, therefore the microbiological activity of (II) was caused by the thiamine formed, and not by (II) itself. Phenylthiazinothiamine (Ia) was shown to be inhibitory to the growth of Kl.apiculata but not to be inhibitory to L.fermenti. Thiamine is extremely absorbable to Kloeckera cells but it was poorly absorbed on cells when (Ia) was present. Competitive inhibition of thiamine uptake on Kloeckera cells was demonstrated by (Ia), but not by (Ib).