Abstract
At least five fluorescent spots other than riboflavin substances were separated on the paper chromatogram of the culture filtrate of Clostridium acetobutylicum. Two of them had violet fluorescence and the remainders had green fluorescence (G, G1 and G2). The production of these compounds in the culture of this bacterium was parallel with the formation of riboflavin. One of the green fluorescent substances (G) promoted the synthesis of riboflavin by resting cells of this microorganism, while the violet fluorescent substance lacked such action.
