What does xylan mean?
Xylan is a complex carbohydrate, or polysaccharide, found in the cell walls of plants. It is composed mainly of sugar units derived from xylose and forms much of the hemicellulose fraction of wood, grasses, and cereal grains. In woody plants, xylan occurs in substantial quantities and helps give plant tissues structural strength and resistance to degradation. It also has technological importance: enzymes called xylanases are used to break it down, including during the production of biofuels and in the processing of animal feed and food. The word is mainly encountered in scientific and industrial contexts, rather than in general conversation. In these settings, xylan may be discussed in terms of its chemical structure, biological role, abundance in a plant material, or usefulness as a source of fermentable sugars. Although it is chemically related to the sugar xylose, xylan is a much larger substance rather than a simple sugar molecule.
nounA branched hemicellulosic polysaccharide composed mainly of xylose units. It occurs in plant cell walls and is especially abundant in wood, grasses, and cereal grains.
- A branched hemicellulosic polysaccharide made chiefly from xylose units and found in the cell walls of plants, particularly in wood, grasses, and cereal grains.
"Xylan makes up a substantial portion of the hemicellulose in hardwood and softwood."
"The researchers used enzymatic treatment to remove part of the xylan from the pulp."
"Xylan is one of the main components of cereal straw and can be converted into fermentable sugars."
Rarely used, since xylan is normally treated as an uncountable substance; the plural may distinguish different types or sources of xylan.
"The researchers compared the xylans obtained from several cereal varieties."
The wood that gives xylan its name also contains it: this complex carbohydrate is a major part of the tough material surrounding plant cells.
Reviewed by Deb Chak, Editor. AI-assisted content curated by RJS Tech Solutions LLP.
Etymology of xylan
Xylan was formed in the 19th century from the Greek xylon, meaning “wood,” together with the chemical suffix -an. Its name reflects the substance's original association with woody plant material. It belongs to a family of Greek-derived scientific words including xylem, xylose, xylophone, and xylography.
How xylan is actually used
This is primarily a technical term in biochemistry, plant science, forestry, and food science. It is normally used as a mass noun.
Easily confused with xylan
Xylan is a plant polysaccharide, whereas xylene is a volatile aromatic hydrocarbon used as a solvent and chemical intermediate.