Polysakkarid

Polysakkarid, the German term for polysaccharide, refers to a broad class of carbohydrate polymers built from long chains of monosaccharide units linked by glycosidic bonds. In English, polysaccharides are defined by their high molecular weight, diverse monosaccharide composition, and varying degree of branching.

Polysakkaride can be categorized as homopolysaccharides, containing a single type of monosaccharide, or heteropolysaccharides, composed of several different sugars. Examples of homopolysaccharides include cellulose (glucose, β-1,4 linkages), starch (amylose and amylopectin, mainly α-1,4 with α-1,6 branches), and glycogen (highly branched α-glucose). Heteropolysaccharides include pectin, agar, and alginates, as well as structural polysaccharides like chitin (N-acetylglucosamine) in fungi and arthropods, and glycosaminoglycans such as hyaluronic acid.

Biosynthesis and degradation: Polysakkaride chains are assembled by glycosyltransferases using activated sugar donors (for example UDP-glucose or ADP-glucose). Their breakdown is carried out by specific hydrolases and lyases, such as amylases, cellulases, and chitinases, enabling energy release or remodeling of extracellular matrices.

Functions: They serve as energy storage (starch in plants, glycogen in animals) and as structural components (cellulose in plants, chitin in fungi and arthropods). Many plant polysaccharides act as gels or thickening agents and contribute to cell wall integrity and defense. In animals, glycosaminoglycans contribute to extracellular matrices and signaling.

Applications: Polysakkaride-based materials are widely used as thickeners, stabilizers, and gelling agents in food and cosmetics. They also have biomedical uses in drug delivery, wound dressings, and tissue engineering, reflecting their versatility and biocompatibility.