Arabinoxylan is a hemicellulose[1] found in both the primary and secondary cell walls of plants, including woods and cereal grains,[2] consisting of copolymers of two pentose sugars: arabinose and xylose.

Structure

Arabinoxylan chains contain a large number of 1,4-linked xylose units. Their backbones are composed of β-D-xylopyranosyl units substituted with single α-L-arabinofuranosyl units.[3] Many xylose units are substituted with 2, 3 or 2,3-linked arabinose residues.[4]

Functions

Arabinoxylans chiefly serve a structural role in the plant cells.[5] They are also the reservoirs of large amounts of ferulic acid and other phenolic acids which are covalently linked to them. Phenolic acids may also be involved in defense including protection against fungal pathogens.

Arabinoxylans are one of the main components of soluble and insoluble dietary fibers which are shown to exert various health benefits.[6] In addition, arabinoxylans, owing to their bound phenolic acids, are shown to have antioxidant activity.[7] Their ion exchange capacity and viscosity are also partly responsible for their beneficial metabolic effects.[8]

References

  1. ^ "Hemicellulosic Polysaccharides". uga.edu. University of Georgia. Archived from the original on April 16, 2021. Retrieved April 1, 2020.
  2. ^ McCartney, L; et al. (2005). "Monoclonal Antibodies to Plant Cell Wall Xylans and Arabinoxylans". Journal of Histochemistry and Cytochemistry. 53 (4): 543–546. doi:10.1369/jhc.4b6578.2005. PMID 15805428.
  3. ^ Marcotuli, Ilaria; Hsieh, Yves S.-Y.; Lahnstein, Jelle; Yap, Kuok; Burton, Rachel Anita; Blanco, Antonio; Fincher, Geoffrey Bruce; Gadaleta, Agata (13 April 2016). "Structural Variation and Content of Arabinoxylans in Endosperm and Bran of Durum Wheat ( Triticum turgidum L.)". Journal of Agricultural and Food Chemistry. 64 (14): 2883–2892. doi:10.1021/acs.jafc.6b00103. hdl:11586/173594. ISSN 0021-8561. Retrieved 5 February 2023.
  4. ^ Dervilly-Pinel, G; et al. (2004). "Investigation of the distribution of arabinose residues on the xylan backbone of water-soluble arabinoxylans from wheat flour". Carbohydrate Polymers. 55 (2): 171–177. doi:10.1016/j.carbpol.2003.09.004.
  5. ^ Wakabayashi K, et al (2005). Physiologia Plantarum. 125:127–134
  6. ^ Izydorczyk, MS; Dexter, JE (2008). "Barley β-glucans and arabinoxylans: Molecular structure, physicochemical properties, and uses in food products–a Review". Food Research International. 41 (9): 850–868. doi:10.1016/j.foodres.2008.04.001.
  7. ^ Rao, RS; Muralikrishna, G (2006). "Water soluble feruloyl arabinoxylans from rice and ragi: changes upon malting and their consequence on antioxidant activity". Phytochemistry. 67 (1): 91–9. doi:10.1016/j.phytochem.2005.09.036. PMID 16289622.
  8. ^ Guillon, F; Champ, M (2000). "Structural and physical properties of dietary fibres, and consequences of processing on human physiology". Food Research International. 33 (3–4): 233–245. doi:10.1016/s0963-9969(00)00038-7.
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