抄録
The authors investigated by paper partition chromatography the crude riboflavin obtained from the broth of submerged culture of Eremothecium ashbyii and found that it contained small quantities of flavin adenine dinucleotide and mononucleotide. The former does not seem to come out into the culture medium until it is decomposed to riboflavin because it is firmly retained in the mycelium despite of its solubility. Therefore, at a proper stage of the culture the mycelium was separated and extracted with pyridine-methanol. Flavin adenine dinucleotide was isolated from the extract and purified by column partition chromatography using starch as a supporter or by a chemical process, riboflavin being removed with benzyl alcohol. The flavin adenine dinucleotide thus obtained was hydrolyzed with hydrochloric acid into flavin mononucleotide and riboflavin, and the activity of the dinucleotide was also confirmed by enzymatic estimation according to the method of Warburg and Christian.
