Xylan

[citation needed] Xylans are polysaccharides made up of β-1,4-linked xylose (a pentose sugar) residues with side branches of α-arabinofuranose and/or α-glucuronic acids.

On the basis of substituted groups xylan can be categorized into three classes i) glucuronoxylan (GX) ii) neutral arabinoxylan (AX) and iii) glucuronoarabinoxylan (GAX).

[10] Some macrophytic green algae contain xylan (specifically homoxylan[11]) especially those within the Codium and Bryopsis genera[12] where it replaces cellulose in the cell wall matrix.

The quality of cereal flours and the hardness of dough are affected by their xylan content,[6] thus, playing a significant role in bread industry.

The main constituent of xylan can be converted into xylitol (a xylose derivative), which is used as a natural food sweetener, which helps to reduce dental cavities and acts as a sugar substitute for diabetic patients.

Xylooligosaccharides produced from xylan are considered as "functional food" or dietary fibers[13] due their potential prebiotic properties.

[23] Jiang et al. (2016) reported a xylan synthase complex (XSC) from wheat that has a central core formed of two members of the GT43 and GT47 families (CAZy database).

They purified xylan synthase activity from wheat seedlings through proteomics analysis and showed that two members of TaGT43 and TaGT47 are sufficient for the synthesis of a xylan-like polymer in vitro.