MOLECULAR ASSOCIATION IN DEXTRAN AND IN BRANCHED AMYLACEOUS CARBOHYDRATES

Abstract

A property of polysaccharides which is of major importance both practically and fundamentally is orderly association between portions of the same or of adjacent molecules.This property depends upon both the physical and chemical constitution of the polysaccharide and data on it provide a means for correlating physical properties with chemical structure.Little specific information is available on molecular association in branched polysaccharides.The industrial importance of starch and the biological significance of glycogen and certain bacterial polysaccharides make such information desirable.This paper presents information on molecular association in the bacterial polysaccharide, dextran from Leuconostoc mesenteroides, and in branched amylaceous substances.Orderly molecular association has been detected by x-ray analysis, and the tendency towards orderly association has been related to the physical and chemical constitution of these polysaccharides.Data are given on typical x-ray diffraction powder patterns of dextran, and on the relation of molecular association to the hydration and ease of dissolution of branched polysaccharides.