1956 年 76 巻 6 号 p. 745-746
Dioscorea Batatas DECNE forma Tsukune MAKINO contains a higher amout of useful components (Table I) and its mucuous liquid, separated from starch and fibers, precipitates a mucous substance on the addition of ethanol to 60% or of hydrochloric acid to 0.15% concentration (Table II). The former dissolves in water to form a viscous liquid but the latter is insoluble in water and forms a viscous liquid only when alkali solution is added, suggesting the role of potassium in the viscosity of such plant roots. The presence of uronic acid in the viscous substance was assumed but the amount detected by the carbonate method and phloroglucinol method were vastly different. The ethanolic solution left after removal of the viscous substance yielded allantoin (0.12%) and γ-aminobutyric acid, as well as 15 kinds of free amino acids, fructose, and galactose. Sixteen kinds of amino acids were detected from the hydrolyzate of the viscous substance but not γ-amino-butyric acid. The sugar detected was mannose alone and presence of amino sugars was not detected.