抗菌性物質の作用機作に関する研究(第1報) : デハイドロ酢酸ナトリウムトFlavinとのInteractionについて

抄録

An evidence was provided that a kind of a complex is formed by interaction between sodium dehydroacetate with flavin in aqueous solution from the result of physicochemical examination proving the following four points. In the presence of sodium dehydroacetate, (1) quenching of fluorescence characteristic to flavin occurs, (2) a change occurs in the ultraviolet absorption spectrum of flavin, the absorption maximum at 445-450 mμ shifing to a longer wavelength region, with decrease in its intensity, (3) photodecomposition of flavin is markedly inhibited, and (4) solubility of sparingly soluble riboflavin increases markedly. Dissociation constant of flavin-sodium dehydroacetate complex was measured by the fluorescence method, absorption spectroscopy, and by the solubilization method and the value was found to be approximately 2 to 6×10^-2 M/L (pH 5.8-8.6, 20°). The site of the dehydroacetic acid molecule interacting with flavin seems to be the enolic hydroxyl in 4-position of its pyrone ring.