Mucilages polysaccharides

Mucilage polysaccharide Mucilage of Dendrobium huoshanense (Orchidaceae) production of IFN-y, IL-10, IL-6, and IL-ltx, and GM-CSF and G-CSF in mice spleen [64]... 

Tomoda, M., Suzuki, Y., and Satoh, N. (1979) Plant mucilages. XXIII. Partial hydrolysis of Abelmoschus-mucilage M and the structural features of its polysaccharide moiety. Chem.Pharm.Bull. 27 1651-1656. 

It is sometimes claimed that mucilage and similar gels may help to maintain hydraulic conductivity between root and. soil (52). However, the hydraulic conductivity of soils is often substantially decreased when soils are irrigated with waste water. Apart from the inducement of sodicity, which is real in many cases, the decreases in hydraulic conductivity are attributed largely to the production of microbial biomass, particularly extracellular polysaccharides (e.g.. Ref. 53). These extracellular polysaccharides form gels that may store large quantities of water and allow water and ions to diffu.se through them at rates not much less than those of free water, but they could be expected to restrict mass flow of water and thus nutrients, to roots (54). 

Polysaccharides are polymers made up of many monosaccharides joined together by glycoside bonds, and include cellulose, starch, vegetable mucilage and plant gums. 

An attempt has been made to classify gums into two main groups (a) real gums which are those plant products which form a clear solution in water and (b) vegetable mucilages which are those which swell but do not dissolve completely in water. This classification is useful but not entirely satisfactory since there are exceptions. Thus gum traga-canth, a tree exudate and a true plant gum, is only partially soluble in water and exhibits those properties normally attributed to mucilages. In this section of the article the term plant gum will be restricted to those complex acid polysaccharides which are exuded from trees either spontaneously or after mechanical injury. 

Closely related to plant gums are those mucilages discussed later which are the complex acid polysaccharides extractable from endosperms of seeds of such plants as flax, quince and lucerne (see below). The acid nature of these mucilages is due to the presence of D-galacturonic acid residues in the complex molecule. ... 

The crude gum tragacanth is a mixture of the salt of a complex acid polysaccharide and a neutral polysaccharide composed principally of L-arabinose residues. Starch is also present in the gum. The acid character of this gum is due to units of D-galacturonic acid and not D-glucuronic acid and it is of interest to note that in its ability to form gels it resembles pectin and the plant mucilages, which also contain D-galacturonic acid. 

In this clas of materials is grouped the majority of the seed mucilages, the acidity of which is due to a uronic acid (usually D-galacturonic acid) or to a methyl ether derivative of a uronic acid. This presence of D-galacturonic acid as the acidic component of the polysaccharide differentiates the mucilages from the gums, the acidity of the majority of which is due to the presence of D-glucuronic acid, or to one of its methyl ether derivatives (see above). 

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