oligosaccaridi

Oligosaccharides are carbohydrates composed of a small number of monosaccharide units linked together by glycosidic bonds. Typically, they consist of between 3 and 10 monosaccharide units, although some definitions extend this range slightly. They are formed through dehydration synthesis, where a molecule of water is removed as each glycosidic bond is created. The specific type and arrangement of monosaccharides, as well as the nature of the glycosidic linkages, determine the properties and functions of an oligosaccharide.

Common monosaccharide units found in oligosaccharides include glucose, fructose, and galactose. Examples of important oligosaccharides include disaccharides like sucrose (glucose + fructose), lactose (glucose + galactose), and maltose (glucose + glucose). Although technically disaccharides are the simplest form of oligosaccharides, the term is often used to refer to chains of three or more monosaccharides.

Oligosaccharides play diverse roles in biological systems. Some are components of cell walls and membranes, contributing to cell recognition and communication. Others serve as energy storage molecules or as signaling molecules. In the human diet, certain oligosaccharides, such as fructans and galactooligosaccharides (GOS), are not easily digested by human enzymes and pass into the large intestine. Here, they can act as prebiotics, selectively stimulating the growth and activity of beneficial bacteria in the gut microbiome, which can have positive effects on digestive health.