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1.
The controlled Smith degradation and limited hydrolysis of glycyrrhizan UA, the main phagocytosis-activating polysaccharide isolated from the root of Glycyrrhiza uralensis FISCHER, was performed. The reticuloendothelial system-potentiating, anti-complementary and alkaline phosphatase-inducing activities of glycyrrhizan UA and its degradation products were investigated. Methylation analyses of primary, secondary and tertiary Smith degradation products and of the limited hydrolysis product indicated that the core structural features of glycyrrhizan UA include a backbone chain composed of beta-1,3-linked D-galactose. All of the galactose units in the backbone carry side chains composed of mainly alpha-1,5-linked L-arabino-beta-1,6- or 1,3-linked D-galactose residues at position 6. Removal of the arabinosyl side chains caused a pronounced decrease in immunological activity.  相似文献   

2.
The controlled Smith degradation of MVS-VI, the major acidic polysaccharide having remarkable anti-complementary activity isolated from the seeds of Malva verticillata L., was performed. Methylation analysis of both the primary and the secondary Smith degradation products indicated that the core structural features of MVS-VI include a backbone chain composed of beta-1,3-linked D-galactose residues. The majority of galactose units in the backbone carry side chains composed of beta-1,3- and beta-1,6-linked D-galactosyl residues at position 6. The controlled Smith degradation products showed considerable anti-complementary activity.  相似文献   

3.
The structural features of MVS-I, the major neutral polysaccharide isolated from the seeds of Malva verticillata L., were elucidated by controlled Smith degradation, methylation analysis, partial acid hydrolysis and enzymic degradation studies. It has a backbone chain composed of beta-1,3-linked D-glucose and D-galactose residues having branches composed of alpha-1,5-linked L-arabinosyl beta-1,4-linked D-galactose and of beta-1,4-linked D-galactosyl beta-1,3-linked D-glucose residues at position 6 of a part of D-galactose units as side chains. MVS-I showed remarkable reticuloendothelial system-potentiating activity in a carbon clearance test.  相似文献   

4.
The controlled Smith degradation of ukonan A, a phagocytosis-activating polysaccharide isolated from the rhizome of Curcuma longa L., was performed. The reticuloendothelial system-potentiating, anti-complementary and alkaline phosphatase-inducing activities of ukonan A and its degradation products were investigated. Methylation analyses of both the primary and the secondary Smith degradation products indicated that the core structural features of ukonan A include a backbone chain mainly composed of beta-1,3-linked D-galactose, beta-1,4-linked D-xylose and alpha-1,2-linked L-rhamnose residues. All of the galactose units in the backbone carry side chains composed of alpha-L-arabino-beta-D-galactosyl or beta-D-galactosyl residues at position 6. Ukonan A has a remarkable effect on each of the three kinds of immunological activities. Periodate oxidation caused pronounced decrease or disappearance of the activities, but the controlled Smith degradation product having the core structure of polysaccharide showed considerable restoration of these activities.  相似文献   

5.
An acidic polysaccharide, designated as cnidirhan AG, was isolated from the rhizomes of Cnidium officinale Makino. It was homogeneous on electrophoresis and gel chromatography, and its molecular mass was estimated to be 5.1 x 10(4). It showed pronounced reticuloendothelial system-potentiating activity in a carbon clearance test, and had a remarkable effect on both anti-complementary and alkaline phosphatase-inducing activities. It is composed of L-arabinose: D-galactose: D-glucuronic acid in the molar ratio of 2:6:1, in addition to small amounts of O-acetyl groups. Methylation analysis, carbon-13 nuclear magnetic resonance, controlled Smith degradation and limited acid hydrolysis indicated that the core structural features of cnidirhan AG include a backbone chain composed of beta-1,3-linked D-galactose residues. Some of the galactose units in the backbone carry beta-D-galactosyl side chains at position 6. Both alpha-L-arabinosyl arabinose side chains and terminal beta-D-glucuronic acid residues are linked to the core galactan units.  相似文献   

6.
The structure of an anti-diabetic polysaccharide (TAP) obtained from the fruiting bodies of Tremella aurantia was investigated by methylation analysis, Smith degradation, partial acid hydrolysis, 13C-NMR spectrometry, and enzymatic digestion. The results suggested that TAP was composed of (1-->3)-linked alpha-D-mannopyranosyl residues as a backbone, some of which were substituted at position 2 with (1-->3)-linked beta-D-xylopyranose side chains and with beta-D-glucopyransyluronic acid at position 4 linked to terminal alpha-D-mannopyranose.  相似文献   

7.
The major acidic polysaccharide, named saposhnikovan A, was isolated from the roots and rhizomes of Saposhnikovia divaricata. It showed remarkable reticuloendothelial system-potentiating activity in a carbon clearance test. It is composed of L-arabinose: D-galactose: D-galacturonic acid in the molar ratio of 6:15:10, and its molecular weight was estimated to be 54000. About 35% of the D-galacturonic acid residues exist as the methyl esters. Methylation analysis, 13C-nuclear magnetic resonance, and controlled Smith degradation studies indicated that the polysaccharide has the alpha-1----4-linked D-galacturonan backbone bearing alpha-1----5-linked L-arabino-beta-3,6-branched D-galactan side chains.  相似文献   

8.
An acidic polysaccharide, named glycyrrhizan GA, was isolated from the stolon of Glycyrrhiza glabra L. var. glandulifera Reg. et Herd. It produced a single band on electrophoresis and a single peak on gel chromatography, and its molecular mass was estimated to be 85,000. Glycyrrhizan GA is composed of L-arabinose: D-galactose: L-rhamnose: D-galacturonic acid: D-glucuronic acid in the molar ratio of 22:10:1:2:1, in addition to small amounts of O-acetyl groups. Part of the hexuronic acid residues exist as methyl esters. Methylation analysis, carbon-13 nuclear magnetic resonance and periodate oxidation studies indicated that its structural features include mainly alpha-arabino-beta-3,6-galactan type structural units. Glycyrrhizan GA showed remarkable reticuloendothelial system-potentiating activity in a carbon clearance test.  相似文献   

9.
An acidic polysaccharide, named saposhnikovan C, was isolated from the roots and rhizomes of Saposhnikovia divaricata Schischk. It was homogeneous as judged by electrophoresis and gel chromatography, and showed remarkable reticuloendothelial system-potentiating activity in a carbon clearance test. It is composed of D-galacturonic acid:L-rhamnose:L-arabinose:D-galactose in a molar ratio of 27:7:8:8, and its molecular mass was estimated to be 132000. About 30% of the D-galacturonic acid residues exist as the methyl esters. O-Acetyl groups were identified, and the content amounted to 3.3%. Methylation analysis, carbon-13 nuclear magnetic resonance, and controlled Smith degradation studies indicated the structural features. It has a pectin-like rhamnogalacturonan backbone with branched arabinan and galactan side chains.  相似文献   

10.
An antitumor polysaccharide containing peptide moieties AT-HW ([alpha]D + 31 degrees in water) and an antitumor polysaccharide AT-AL ([alpha]D + 209 degrees in 1 M sodium hydroxide) were isolated from hot-water extract and the alkaline extract of the fruiting bodies of Armillariella tabescens, respectively. Chemical structures of AT-HW and AT-AL were investigated by a combination of chemical and spectroscopic methods. The results indicate that the major constituent of AT-HW (molecular weight, 105000), a heteroglycan, is composed primarily of beta-(1----6)-linked D-glucopyranosyl and D-galactopyranosyl residues, and contains their branched residues and terminal sugar (gluco-, manno-, and fucopyranose) residues, in addition to beta-(1----3)-linked D-glucopyranosyl residues, while AT-AL (molecular weight, 93000) is chiefly composed of alpha-(1----3)-linked D-glucopyranosyl residues.  相似文献   

11.
从山茱萸中提取出水溶性粗多糖, 经柱色谱分离纯化得到一种酸性多糖组分FCP5-A. 采用高效凝胶渗透色谱法(HPGPC)测定其为均一性多糖, 平均分子量为8.7×104. 经IR、GC、部分酸水解、13C NMR及甲基化分析等方法对该多糖的化学结构进行了表征. 结果表明, 该多糖由鼠李糖、阿拉伯糖、半乳糖及半乳糖醛酸组成, 其摩尔比为1∶5.7∶0.6∶1.2. FCP5-A为多分支结构, 由-2)Rha(1-及-4)GalA(1-构成主链, 在鼠李糖的4位存在分支; 支链主要由高度分支的阿拉伯糖构成, 此外还存在-3)Gal(1-; 末端残基为Ara(1-及Gal(1-. 结果提示, FCP5-A为一种新的山茱萸酸性分支多糖.  相似文献   

12.
The structure of the capsular polysaccharide from Klebsiella type 57 has been investigated. Methylation analysis, uronic acid degradation, modified Smith degradation and graded acid hydrolysis were the principle methods used. Pure oligomeric fragments were isolated using the three methods of degradation and characterized by chemical and physical methods. These studies show the structure to consist of a tetrasaccharide repeating unit (all sugar residues have the D-configuration and are pyranosidic).  相似文献   

13.
Methylation studies and partial acid hydrolysis have been carried out on the extracellular polysaccharide produced by the diatom Chaetoceros curvisetus. The polysaccharide contains the sugars galactose, rhamnose, and fucose and is partially sulfated. The presence of fucose in both furanose and pyranose forms within one molecule is reported for the first time. The fucofuranose is present as end groups, 1,2-linked and as branch points. Fucopyranose is mainly present as branch points in the polysaccharide, some being 1,3-linked, and a small fraction as end groups. The main part of rhamnose is 1,2-linked and galactose is mainly 1,3-linked.  相似文献   

14.
研究了由大粒车前子多糖分离纯化所得组分PLP-1的一级精细结构特征. 通过单糖组成分析、部分酸水解及甲基化分析,并结合NMR,GC和GC-MS等技术测定了PLP-1的一级结构. 结果表明,PLP-1由Ara(33.98%),Xyl(58.23%),Rha(2.36%),Glc(2.23%),Gal(2.36%)和Man(0.83%)组成,糖醛酸以GlcA形式存在. PLP-1中主要糖残基有α-T-linked Araf(9.58%),β-T-linked Xylp(8.71%),α-1,3-linked Araf(18.22%),β-1,3-linked Xylp(8.05%),β-1,4-linked Xylp(5.85%),β-1,2,4-linked Xylp(16.98%)和β-1,3,4-linked Xylp(27.52%),GlcA以α-T-linked GlcAp形式存在;此外还有1,2-linked Rhap,T-linked Glcp,1,6-linked Glcp,T-linked Galp,1,3-linked Galp和1,3,6-linked Galp等少量其它残基. 根据所得结果推断出PLP-1可能的一级结构.  相似文献   

15.
The hot-water extract of the spores of Ganoderma lucidum was shown to have a stimulating effect on concanavalin A-induced mitogenic activity of T lymphocytes. Bioassay-guided separation led to the isolation of a polysaccharide with potent T lymphocyte-stimulating activity by ethanol fractionation, anion-exchange, and size-exclusion chromatography. Based on the composition and methylation analyses, periodate oxidation, Smith degradation, and NMR spectroscopy, the native polysaccharide was shown to be a beta-D-(1-->3)-glucan with branches of terminal glucosyl residues substituted at C-6 of the glucose residues in the main chain. The branching ratio is approximately 20%. A series of sulfated or carboxymethylated derivatives were prepared and their structural features were elucidated by chemical and spectral analyses. The solution conformation and T lymphocyte proliferation effect of the glucans before and after derivatization were compared and discussed. The data obtained indicate that the introduction of ionic groups would significantly affect the original conformation of the native glucan in aqueous solution and further affect T lymphocyte-stimulating activity. The triple-helical structure of the glucans, the nature of the ionic groups, and the density of negative charge were considered to be closely related to this activity.  相似文献   

16.
Structural Features of a Polysaccharide from Centella asiatica   总被引:3,自引:0,他引:3  
Centella asiatica has been used as remedy for sodation, stabilization and against lepra, anabrosis1 in the oriental countries. The low-molecular-weight constituents in Centella asiatica have been investigated1. However, no polysaccharides have been reported. 1BI was the first polysaccharide isolated from C. asiatica, which had immunostimulating activity in vitro. In present study, we report the structural features of 1BI. Experimental Extraction, isolation and purification Dried C.…  相似文献   

17.
Five kinds of chemically modified products were prepared from Plantago-mucilage A, the representative mucous polysaccharide isolated from the seed of Plantago asiatica L., and their reticuloendothelial system-potentiating and alkaline phosphatase-inducing activities have been investigated. Both activities were markedly enhanced when the mucilage was de-O-acetylated. The products obtained by periodate oxidation, controlled Smith degradation, and partial acid hydrolysis under the two conditions were not effective. Structural features of the partial hydrolyzates were elucidated, and it was shown that these products lost all O-acetyl groups, all xylose branches and many hexuronosyl arabinose side chains.  相似文献   

18.
Abstract

Juniperus tibetica Kom., a common forest species in Tibet, has been traditionally used in Tibetan medicine to treat rheumatic arthritis. In order to investigate the effective substances of J. tibetuca, anticomplent assay-guided fractionation using gradient anion-exchange chromatography and gel permeation chromatography was applied to the crude polysaccharides of the twigs and leaves of J. tibetica and led to the isolation of a homogenous polysaccharide, YB-PS. It exhibited a robust anticomplement activity (CH50: 461?±?10?μg/mL) through the classical pathway of complement system activation by targeting complement components C1q, C3, C4 and C5. The structure of YB-PS was studied by monosaccharide composition and methylation analyses, 1?D, 2?D NMR data and scanning electron microscope. The results indicated that YB-PS was composed of Ara, Gal, and Glc with a molar ratio of 5.8:3.0:1.2. Its backbone was comprised of 1,3-linked α-Araf, 1,3,5-linked α-Araf, 1,2,4-linked α-Galp, and 1,3-linked α-Glcp with terminal α-Araf, β-Galp and 1,4-linked β-Galp as branches. YB-PS was found to have a sheet structure with smooth surface. This study provided scientific foundation for YB-PS as a potential complement inhibitor to treat diseases involved with excessive activation of the complement system.  相似文献   

19.
A neutral polysaccharide, named glycyrrhizan UC, was isolated from the root of Glycyrrhiza uralensis Fischer. It was homogeneous on electrophoresis and gel chromatography, and its molecular mass was estimated to be 69,000. Glycyrrhizan UC is composed of L-arabinose:D-galactose:D-glucose:L-rhamnose in the molar ratio of 10:30 27:1. Methylation analysis, carbon-13 nuclear magnetic resonance and periodate oxidation studies indicated its structural feature as an arabino-3,6-galacto-glucan type polysaccharide.  相似文献   

20.
This article reports the isolation and structural investigation of an acidic polysaccharide of the seeds of Prunus armeniaca (apricot) - a plant of commercial importance. The polysaccharide is composed of three sugars - mannose (50%), glucose (37.5%) and glucuronic acid (12.5%). The results of methylation analysis, partial depolymerisation, Smith degradation and NMR spectroscopic studies indicate a branched structure consisting of a straight chain of mainly alpha-(1 --> 3)mannan, which is interspersed with 4-O-(beta-D-mannopyranosyl)glucuronic acid residues. The side chain is bound to the alpha-mannan chain in the form of a trisaccharide of the glucose.  相似文献   

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