亜硫酸塩によるトリプトファンの分解に関する研究(第1報) : インジゴチン, インジルビンその他の分解物の分離, 確認

抄録

When a sulfite, usually used as a stabilizer, is added to an aqueous solution containing tryptophan, there appears complex phenomena like coloration, fluorescence, and precipitation. Effect of sulfites on tryptophan is not well known, some claiming acceleration of decomposition, some maintaining stabilization, and there has been no report on the nature of this decomposition product. It was found that tryptophan is decomposed by a sulfite in the presence of oxygen and the decomposition product thereby formed was examined. Among dozens of decomposition products, most of the substances were identified or presumed, with the exception of a few. Since these products were all oxidation products and since one of the components of fluorescent materials, dehydroindigo disulfonicacid, was considered to be the intermediate of the blue precipitate of indigotin, concurrent addition of sulfite was found to have occurred. The fact that the sulfites, which are often used as the stabilizer, may cause oxidative or additive decomposition of some of the ingredients must be taken into consideration in future studies on drug preparation.