Involvement of the Complex Polysaccharide Structure of Pectin in Regulation of Biological Functions

Abstract

The water-soluble dietary fiber, pectin, is a polysaccharide present in the cell wall of terrestrial plants. It is a polymer of d-galacturonic acid polymerized by alpha-1,4 linkages and has side chains composed of 13 different sugars. Due to its complex chemical structure, pectin has a number of physical characteristics, including gelling properties and viscosity, and has physiological functions in vivo. The degree of esterification of the pectin main chain affects gelling. In addition, the side chain structure has been shown to affect antitumor activity and regulation of intestinal immunity, which are well-known physiological functions of pectin, and the rhamnogalacturonan-I region is particularly important. This review discusses the correlations between the molecular structure of pectin and its functions. Not only that, we will discuss the mechanisms and physiological significance of small intestinal villus morphological changes, which is still a mysterious function of pectin.