Amino Acids of Potato Tubers, Etiolated Sprouts, and Foliage

1. The free and combined amino acids of Russet Burbank potato tubers, etiolated sprouts, and foliage were determined by paper-chromatographic methods. 2. Aspartic acid, glutamic acid, glutamine, alanine, γ-aminobutyric acid, and valine were the prominent amino acids detected free in tubers, sprouts, and foliage. Asparagine, though conspicuous in tubers and sprouts, was present in small quantities in the foliage. Four unknown materials reacting with ninhydrin to give blue colors were detected. 3. Valine, the leucines, alanine, aspartic acid, glutamic acid, arginine, and lysine were prominent constituents of the acid-hydrolyzed fractions of tubers, sprouts, and foliage. Hydroxyproline was detected only in sprout and foliage hydrolysates. Five unknown materials reacted with ninhydrin.