Polysaccharides arabinan

Cardoso, S. M., Silva, A. M., and Coimbra, M. A., Structural characterisation of the olive pomace pectic polysaccharide arabinan side chains. Carbohydr Res 2002, 337 (10), 917-24. 

Glucomannans Mannans Xylans Xyloglucans Pectic polysaccharides Arabinans Arabinogalactans Galactans Galacturonans Rhamnogalacturonans... 

The pentosan polysaccharides, xylan and arabinan, commonly known as hemiceUulose, are the principal precursors of furfural and are always found together with lignin and cellulose in plant materials. 

Arabinan. This highly soluble polymer is found in the extracts of many fmits and seeds, in the boiling water extracts of pine wood (127), in the extracts of marshmallow roots (A/t/jaea officina/is) (128), and aspen (63) and willow (Sa/ix a/ba F) (129) bark. Because arabinan can be isolated from mildly degraded pectin fractions, it is often difficult to determine whether it is a hemiceUulose or a labile fragment of a larger polysaccharide and/or lignin complex. Arabinans have a complex stmcture composed almost entirely of 5-linked a-L-arabinofuranosyl units with similar residues linked to them at C-2 and/or C-3 and is soluble in 70% aqueous methanol solution. 

Echinacea-polysaccharide II consists of arabino-3,6-P-galactan part, rhamnogalacturonan part and arabinan part [5], therefore it is suggested that the polysaccharide may be certain ramified region of pectic polysaccharide. 

A cell-wall polysaccharide fraction remaining after treatment with a "classical" pectinase is termed rhamnogalacturonan (RG) or modified hairy regions (MHR). It is characterized by a highly branched ihamnogalacturonan-polymer with some arabinan side chains. 

Signals having low shifts were also detected on examination of two structurally related polysaccharides (from Rosa glaucai) containing a-L-arabinofuranosyl residues.18 In the study, one of the two arabinans... 

Hydrolysis of mannan-type polysaccharides by P-mannanase is dependent on substitution on and within the main-chain as well as the source of the P-mannanase employed. Characterisation of reaction products can be used to define the sub-site binding requirements of the enzymes as well as the fine-structures of the polysaccharides. Action of c/xt/o-arabinanase and em/o-galactanase on arabinans and arabinogalactans is described. Specific assays for ndo-arabinanase and arabinan (in fruit-juice concentrates) are reported. 

A number of polysaccharides have been associated with beverage hazes or floes. These include arabinans in red wine (Belleville et al.,... 

Figure 3.2 Structures of the pectic polysaccharides homogalacturonan (HG) and rhamnogalacturonan I (RG-I). (1 — 5)-a-Arabinan, (1 — 4)-P-galactan and arabino-4-galactan are side chains of RG-I.

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