Polysaccharides

The three types of carbohydrate are:
*Monosaccharides
*Disaccharides
*Polysaccharides

Polysaccharides are major classes of biomolecules. Polysaccharides are classified as complex carbohydrates because they are composed of many sugars units linked together. Polysaccharides form when monosaccharides or disaccharides link together by glycosidic bonds.

Polysaccharides are the largest component of biomass. It is estimated that more than 90% of the carbohydrate mass in nature is in the form of polysaccharides.

The most important polysaccharides in nutrition are starch and fiber. Starch is composed of hundreds or thousands of glucose unit linked together to form long chains. It is found largely in plants, fruits, seeds, etc.

A single long chain of glucose units is called amylose; when the glucose chain contains branch points it is called amylopectin. About three-fourth of starch found in nature is amylopectin.

Amylose is a polysaccharide made of α-D-glucose units, bonded to each other through α(1→4) glycosidic bonds. Amylose constitutes 5–35% of most natural starches and has a major influence over starch properties in foods.

Starch is the main storage form of energy in plants that human take advantage of, by harvesting the plants and incorporating the starchy foods into diets.

Dietary fibers is a collective tern used to describe all non-starch polysaccharides that cannot be digested. Dietary fiber is often further distinguished as soluble or insoluble fiber based on its solubility to dissolve in water. Dietary fiber — found mainly in fruits, vegetables, whole grains and legumes — is probably best known for its ability to prevent or relieve constipation.
Polysaccharides