Studies on Cecum Digestion

VI. Free Amino Acids in the Cecal Contents, Hard Feces, and Soft Feces of the Rabbit

Abstract

Distribution of free amino acids was investigated in the cecal contents, hard feces, and soft feces of three rabbits which had been used in the previous experiment (this Journal, 31: 181, 1960), by using paper-chromatography.
The results obtained are summarized as follows.
1) Most kinds of amino acids were found at free state in every case. Considerably similar distribution of these was observed among the cecal contents, hard feces, and soft feces, except in a few cases.
2) Glycine, alanine, valine, leucine, isoleucine, aspartic acid, and glutamic acid were found in large quantities in every sample. On the other hand, hydroxyproline, cystine, methionine, and ornithine were detected much less, and tryptophane, methionine-sulphone, taurine, asparagine, and glutamine scarcely.
3) Beta-alanine and γ-amino-n-butyric acid, as ω-amino acids, were found in all samples from two rabbits tested.
4) Leucine was separated successfully by using two-dimensional chromatography with the following solvents. First dimension=n-butanol: methyl ethyl ketone: 17N ammonia: water (5:3:1:1, V/V); second dimension=2, 4-lutidine: aniline (9:1, V/V), water-saturated.