Abstract
The growth of Lactobacillus arabinosus or Saccharomyces carlsbergensis was inhibited by INAH-N-oxide added in the medium containing a minimum amount of requisite vitamins. The growth inhibitory effect of INAH-N-oxide was a little weaker than INAH but stronger than Na-glucuronate isonicotinohydrazone. The growth inhibition of INAH-N-oxide was recovered by pyridoxal or pyridoxamine on L. arabinosus and by any of three vitamins of B_6 group on Sacch. carlsbergensis. The activity of tryptophanase of Escherichic coli was inhibited by INAH-N-oxide and the inhibition was recovered by the vitamins of B_6 group. These results indcated that INAH-N-oxide was antimetabolite of vitamin B_6 as INAH and Na-glucuronate isonicotinohydrazone.
