Pectic polysaccharides and their functional properties

Abstract

Since their first discovery in 1790–1825, pectins are still fascinating plant and food scientists who continue to carry out numerous structural as well as functional studies on them. This great interest of scientists for pectins is accounted for by their large spectrum of (bio)functionalities, starting from their natural location in plant cell walls as bioactive components for cell growth, defense, and protection via diverse manufactured food and nonfood products as techno-functional (gelling, emulsifying, film-forming, etc.) agents to terminate in human welfare as health-benefit (prebiotic, anticomplementary, antioxidant, anticancer, etc.) agents. The extraordinary functional versatility of pectins is thought to be intimately related to fine structure. Unfortunately, structurally, pectins are extremely diversified that establishment of structure-function relationship appeared so far a difficult task to go through. On the other hand, the extended structural variability of pectins presages for the finding of new functions hitherto unknown. Nevertheless, for some structurally well-known pectic cobiopolymers such as homogalacturonan, solid evidence for structure-related functions, especially gelling properties, has been provided, including new insights very recently. After a brief introduction on the “pectin structural repertoire,” the main sources of industrial pectins will be exposed, followed by a succinct structural description of the different pectic block cobiopolymers, commonly referred to as “pectic polysaccharides.” Finally, some remarkable structure-related functions, namely, gelling, emulsifying/emulsion-stabilizing, and antitumor properties of pectins will be revisited in the light of the latest work.