Polysaccharides from plants

Figure 9 from Paulsen BS (ed) Bioactive Carbohydrate Polymers. Yamada H (2000) Bioactive plant polysaccharides from Japanese and Chinese traditional herbal medicines , p 15-p24. Kluwer Academic Publishers, with permission from Springer. 

Polysaccharides from Plant Polysaccharides from Plants ... 

Hemicellulose [9034-32-6] is the least utilized component of the biomass triad comprising cellulose (qv), lignin (qv), and hemiceUulose. The term was origiaated by Schulze (1) and is used here to distinguish the nonceUulosic polysaccharides of plant cell walls from those that are not part of the wall stmcture. Confusion arises because other hemicellulose definitions based on solvent extraction are often used in the Hterature (2—4). The term polyose is used in Europe to describe these nonceUulosic polysaccharides from wood, whereas hemicellulose is used to describe the alkaline extracts from commercial pulps (4). The quantity of hemicellulose in different sources varies considerably as shown in Table 1. 

Historically, dietary fiber referred to iasoluble plant cell wall material, primarily polysaccharides, not digested by the endogenous enzymes of the human digestive tract. This definition has been extended to iaclude other nondigestible polysaccharides, from plants and other sources, that are iacorporated iato processed foods. Cellulose [9004-34-6] (qv) is fibrous however, lignin [9005-53-2] (qv) and many other polysaccharides ia food do not have fiberlike stmctures (see also Carbohydrates). 

Abstract Polysaccharides from plants have been the subject of studies for a very long time, mainly focussed on their physical properties, their chemical and physical modification, and their application. Over the last 20 years there has heen increasing interest... 

A 3-deoxyheptulosaric acid has been found in the LPS from Acineto-bacter calcoaceticus NCTC 10305. Another acid of this class, 3-deoxy-o-/yxo-heptulosaric acid ° (30), is a component of a plant polysaccharide. One 4-deoxyhexulosonic acid, of unknown configuration, is known and is a component of the E. coli K3 capsular polysaccharide. "... 

Wagner et al. obtained immunostimulating pectic polysaccharides from plant cell culture of Echinacea purpurea [5]. From the extracellular polysaccharide... 

In some cases pectinolytic enzymes have been associated with virulence and it is generally accepted that pectinolysis by these bacteria facilitates their entry and spread in plant tissue. In Rhizohium, these enzymes may play a role in the root infection process that precedes nodule formation (Hubbell et al 1978). A. irakense has never been reported to be pathogenic on plants. It can therefore be speculated that moderate and strictly regulated pectinolysis of A. irakense facilitates entry in the outer cortex of plants roots, since A. irakense has been isolated from surface-sterilized roots. It is likely that breakdown of plant polysaccharides by root colonizing bacteria can provide them with extra carbon source. 

Nowadays there is scientific evidence that, besides plant polysaccharides and lignin, other indigestible compounds such as resistant starch, oligosaccharides, Maillard compounds, and phytochemicals—mainly polyphenols—can be considered DF constituents (Saura-Calixto and others 2000). Of these substances, resistant starch is a major constituent in cereals, whereas phytochemicals are the most important such substance in fruits and vegetables. Here, we address mainly polyphenols and carotenoids associated with DF in fruits and vegetables because of the important biological properties derived from them. 

Roesler, I. et al., Application of purified polysaccharides from cell cultures of the plant Echinacea purpurea to mice mediates protection against systemic infections with Listeria monocytogenes and Candida albicans, Int J Immunopharmacol, 13, 27, 1991. 

For monitoring the extent of polysaccharide hydrolysis, l.c. methods that sepeu ate and analyze the non-fermentable oligosaccharides (d.p. 3-30) derived from cellulose, hemicellulose, and pectins are useful, and have already been described (see Section III,l,c). For determination of the monosaccharide composition of completely hydrolyzed, plant polysaccharides, l.c. is especially useful and has been applied to the compositional analysis of hydrolyzed plant fiber,wood pulps,plant cell-walls,and cotton fibers.In these representative examples, the major sugars of interest, namely, glucose, xylose, galactose, arabinose, and mannose, have traditionally been difficult to resolve by l.c. The separa-... 

Jhon Castaneda-Gomez is a native of Manizales, Colombia. He obtained his B.Sc (1999) from the University of Caldas and his M.Sc. (2007) from Del Valle University in Colombia. He has completed two years of the Ph.D. program at the School of Chemistry, National Autonomous University of Mexico, and working at the Department of Pharmacy on the development of analytical techniques for the isolation of complex polysaccharides from plant sources. 

The starches, the most important vegetable reserve carbohydrate and polysaccharides from plant cell walls, are discussed in greater detail on the following page. Inulin, a fructose polymer, is used as a starch substitute in diabetics dietary products (see p.l60). In addition, it serves as a test substance for measuring renal clearance (see p.322). 

As a result of heparin s multiplicity of biological activities and its importance as a major pharmaceutical, other polysaccharides and modified polysaccharides have been examined as potential heparin analogues in drug development (1). These heparin analogues include other GAGs, other non-GAGs, sulfated polysaccharides from plant and animal origins such as lam-... 

Wang, S. C, Shan, J. J., Wang, Z. T., and Hu, Z. B. (2006). Isolation and structural analysis of an acidic polysaccharide from Astragalus membranaceus (Fisch.) Bunge.. Integr. Plant Biol. 48, 1379-1384. 

Incubation of D-[U-I4C]apiose with sterile Lemma minor (duckweed) produced less than 0.01% incorporation into the cell-wall polysaccharides.75 Most of the d-[U-i4C]apiose appeared as 14C02 some remained in solution in the medium and in the duckweed plants, primarily as degradation products of D-[U-14C]apiose, but not as the branched-chain sugar.75 There is an efficient synthesis of the [U-14C]apiose moiety of cell-wall polysaccharides from D-[U-14C]glucose under similar conditions.81 Of the plant tissues tested, only L. minor contained an enzyme system able to metabolize free apiose. Carrot, lettuce, and spinach tissues are unable to metabolize the free, branched-chain sugar.75... 

The involvement of glycolipid and glycoprotein intermediates in the synthesis of polysaccharides from glycosyl-nucleotides in plants is considered to be a likely possibility. Such intermediates could act as specific primers, or acceptor substrates, for the formation of polysaccharides. Furthermore, subunits of complex heteropolysaccharides could be assembled on such intermediates, and later incorporated into polysaccharides, or directly cross-linked into the cell wall. Evidence of the involvement of such intermediates in the synthesis of polysaccharides in a number of organisms is presented in Sections XII,3,b and XII,3,c. 

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