Chemistry:Arabinose

From HandWiki
Arabinose
DL-Arabinose.svg
Names
IUPAC name
Arabinose
Other names
Pectinose
Identifiers
3D model (JSmol)
ChEBI
ChemSpider
EC Number
  • 205-699-8
UNII
Properties[1]
C5H10O5
Molar mass 150.13 g/mol
Appearance Colorless crystals as prisms or needles
Density 1.585 g/cm3 (20 °C)
Melting point 164 to 165 °C (327 to 329 °F; 437 to 438 K)
834 g/1 L (25 °C (77 °F))
-85.70·10−6 cm3/mol
Hazards
NFPA 704 (fire diamond)
Flammability code 1: Must be pre-heated before ignition can occur. Flash point over 93 °C (200 °F). E.g. canola oilHealth code 1: Exposure would cause irritation but only minor residual injury. E.g. turpentineReactivity code 0: Normally stable, even under fire exposure conditions, and is not reactive with water. E.g. liquid nitrogenSpecial hazards (white): no codeNFPA 704 four-colored diamond
1
1
0
Related compounds
Related aldopentoses
Ribose
Xylose
Lyxose
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
☒N verify (what is ☑Y☒N ?)
Infobox references

Arabinose is an aldopentose – a monosaccharide containing five carbon atoms, and including an aldehyde (CHO) functional group.

Properties

For biosynthetic reasons, most saccharides are almost always more abundant in nature as the "D"-form, or structurally analogous to D-glyceraldehyde.[note 1] However, L-arabinose is in fact more common than D-arabinose in nature and is found in nature as a component of biopolymers such as hemicellulose and pectin.[2]

The L-arabinose operon, also known as the araBAD operon, has been the subject of much biomolecular research. The operon directs the catabolism of arabinose in E. coli, and it is dynamically activated in the presence of arabinose and the absence of glucose.[3]

A classic method for the organic synthesis of arabinose from glucose is the Wohl degradation.[4]

D-Arabinose
Alpha-D-Arabinofuranose.svg
α-D-Arabinofuranose
Beta-D-Arabinofuranose.svg
β-D-Arabinofuranose
Alpha-D-Arabinopyranose.svg
α-D-Arabinopyranose
Beta-D-Arabinopyranose.svg
β-D-Arabinopyranose

Etymology

Arabinose gets its name from gum arabic, from which it was first isolated.[5]

Use in foods

Originally commercialized as a sweetener, arabinose is an inhibitor of sucrase, the enzyme that breaks down sucrose into glucose and fructose in the small intestine.[6]

See also

Notes

  1. The D/L nomenclature does not refer to the molecule's optical rotation properties but to its structural analogy to glyceraldehyde.

References

  1. Weast, Robert C., ed (1981). CRC Handbook of Chemistry and Physics (62nd ed.). Boca Raton, FL: CRC Press. p. C-110. ISBN 0-8493-0462-8. 
  2. Holtzapple, M.T. (2003). "HEMICELLULOSES". Encyclopedia of Food Sciences and Nutrition (2nd edition): 3060–3071. doi:10.1016/B0-12-227055-X/00589-7. ISBN 9780122270550. 
  3. Watson, James (2003). Molecular Biology of the Gene. pp. 503. 
  4. Braun, Géza (1940). "D-Arabinose". Organic Syntheses 20: 14. http://www.orgsyn.org/demo.aspx?prep=CV3P0101. ; Collective Volume, 3, pp. 101 
  5. Merriam Webster Dictionary
  6. Krog-Mikkelsen, Inger; Hels, Ole; Tetens, Inge; Holst, Jens Juul; Andersen, Jens Rikardt; Bukhave, Klaus (2011-08-01). "The effects of L-arabinose on intestinal sucrase activity: dose-response studies in vitro and in humans". The American Journal of Clinical Nutrition 94 (2): 472–478. doi:10.3945/ajcn.111.014225. ISSN 1938-3207. PMID 21677059.