Submitted to: Book Chapter
Publication Type: Book / Chapter
Publication Acceptance Date: 10/1/2005
Publication Date: 8/1/2006
Citation: Eggleston, G., Doyle, J.P. 2006. Polysaccharides: molecules, clusters, networks and interactions. Oxford University Press. Chapter 2, pp. 19-35. Interpretive Summary: This book chapter reviews the structural organization of polysaccharides, which are long chain sugars. It is the different structures of polysaccharides that govern their very different physical properties and technical applications. These include water solubility, viscosity, aggregation and crystallization, gelation in foods, digestability in foods and biological recognition in plants and animals. This book will help scientists and technologists understand the different properties of polysaccharides, and help them to use them better.
Technical Abstract: This paper reviews the structural organization of polysaccharides with respect to molecules, clusters (aggregates), networks and interactions. As for proteins, different levels of structural organization exist for polysaccharides. The primary structure describes the covalent sequence of monosaccharide residues in the polymer chain; the secondary "ordered" structure defines any geometrically regular arrangement in space that this sequence may adopt; the tertiary structure defines the way these arrangements pack together and higher quarternary structures mostly define polysaccharide-polysaccharide interactions. Up-to-date experimental techniques to characterize secondary and higher structural organization are described. Polysaccharide clusters and gel networks are illustrated with carrageenan, alginate, pectin, and gellan. Higher levels of structural organization (polysaccharide-polysaccharide interactions), are discussed for the synergistic interactions of galactomannans or konjac glucomannans with helix-forming algal polysaccharides or xanthan. Finally the future outlook for the fast growing area of the three-dimensional structure of polysaccharides at the molecular level is discussed.