Oligosaccharides

Oligosaccharides are carbohydrates composed of a small number (typically 3–10) of monosaccharide units (simple sugars) linked together by glycosidic bonds.


Explanation:
Oligosaccharides are intermediate in size between simple sugars (monosaccharides and disaccharides) and complex carbohydrates (polysaccharides). They can be either:

  • Naturally occurring (found in foods like onions, garlic, leeks, asparagus, legumes, and human breast milk)
  • Synthesized or added (as prebiotics or in processed foods)

There are two main types:

  • N-linked oligosaccharides: attached to proteins via the nitrogen atom of an asparagine side chain
  • O-linked oligosaccharides: attached to proteins via the oxygen atom of serine or threonine side chains

Functions:

  1. Cell Recognition and Communication: Often found on glycoproteins and glycolipids on the cell membrane, they play roles in immune response and cellular signaling.
  2. Prebiotic Role: Some, like fructo-oligosaccharides (FOS) and galacto-oligosaccharides (GOS), support gut health by feeding beneficial gut bacteria.
  3. Influence on Digestion: Most oligosaccharides are not digested in the upper gastrointestinal tract and are instead fermented in the colon, potentially causing gas and bloating in some individuals.