METABOLISM OF BARBITAL BY STREPTOMYCES MEDITERRANEI.

The metabolism of barbital in cultures of Streptomyces mediterranei was studied. Small quantities were transformed during the fermentation. Four compounds were isolated and identified as 5-ethyldialuric acid, 5-ethylbarbituric acid, 5-(beta-hydroxyethyl)-5-ethylbarbituric acid, and diethylmalonic acid monoureid. The influence of these compounds on the production of rifamycin was of minor importance. With the aid of C(14)-barbital, it was established that neither barbital nor any of its metabolic products can be considered as precursors of the rifamycin B.