Xylan is a group of hemicelluloses that reside in plant cells walls and also can be found in some algae (both green and red). Xylans are polysaccharides whose backbone consists of beta-1,4-linked xylosyl residues. This backbone can be substituted with side-chains of arabinosyl, glucuronosyl, and 4-O-mthylglucuronosyl residues, and can also be further modified by acetyl substitution on the hydroxyls of the xylosyl residues.
