Hydration effects of amino-compounds

Abstract

The chief interest in the results presented in this brief paper depends upon the following facts and conditions:

A. The amino-compounds furnish the only known solutions in which agar and other pentosans or mucilages undergo a greater hydration than in distilled water. Tentative conclusions to this effect have been confirmed by all of the results obtained during the past year. 1

B. The pentosans, or anhydrides of the 5-carbon sugars are universally and abundantly present in plant cells, originating by transformations of wall-material, starch, etc., in any part of the protoplast, and presumably intimately interwoven into its colloidal mesh. In animals the pentosans seem to be confined to the nucleo-proteins, and the manner of their origin is not so clear in this case.

C. The mucilages, gums and slimes in which form these substances appear in definite masses in syneretic cavities and in layers in the plant cell have a hydration capacity enormously greater than that of the sugars from which they are derived, and show a wide range of solubility and other qualities.

D. The pentosans are subject to digestion in animals to an extent variously assigned by different authors, These substances undergo metabolic changes in the plant but slowly. Wherever they occur they must show changes in volume and form according to the colloidal structure in which they occur and to the nature of the solutions penetrating them.

Our own experimentation has been made principally with agar and some of the common plant gums, separately and in mixtures with albumins. The revised generalizations which we are prepared to support may be briefly stated in the following summary;