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1.
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   

2.
From rhizomes of Panax japonicus (Araliaceae), two polysaccharides named tochibanan-A and -B, which show reticuloendothelial-potentiating activity in the carbon clearance test in mice, were isolated. The structure of tochibanan-A (molecular mass: 23,000) was elucidated as a linear beta-1,4-D-galactan. Tochibanan-B (molecular mass: 40,000) consists of D-galactose (87.1%), L-arabinose, D-glucose and D-galacturonic acid and has a beta-D-(1----4)-linked galactopyranosyl backbone possessing GalA-(1----6)-Gal, Ara-(1----5)-Ara, Gal, and Glc side chains. The structure around the branching points and the repeating unit were investigated and a possible structure of tochibanan-B is proposed.  相似文献   

3.
A polysaccharide has been isolated from the leaves ofPhytolacca americana and has been characterized. It has been established that it contains residues of galactose, arabinose, xylose, and rhamnose, in a ratio of 3:4:1:3 and also D-galacturonic acid (85–90%). The results obtained permit the polysaccharide to be assigned to the class of pectin substances.  相似文献   

4.
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   

5.
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   

6.
An acidic polysaccharide, designated as AMon-S, was isolated from the roots of Astragalus mongholicus BUNGE. It was homogeneous on electrophoresis and gel chromatography, and its molecular mass was estimated to be 7.6 x 10(4). It showed significant reticuloendothelial system-potentiating activity in a carbon clearance test. It is composed of L-arabinose: D-galactose: D-galacturonic acid: D-glucuronic acid in the molar ratio of 18:18:1:1, in addition to small amounts of O-acetyl groups and peptide moiety. A part of the hexuronic acid residues exist as the methyl esters. Methylation analysis, carbon-13 nuclear magnetic resonance and periodate oxidation studies enabled elucidation of its structural features and revealed mainly alpha-arabino-beta-3,6-galactan type structural units.  相似文献   

7.
A neutral polysaccharide, named ukonan D, was isolated from the rhizome of Curcuma longa L. It produced a single band on electrophoresis and a single peak on gel chromatography, and its molecular mass was estimated to be 28,000. It showed remarkable reticuloendothelial system-potentiating activity in a carbon clearance test. Ukonan D is composed of L-arabinose: D-galactose: D-glucose: D-mannose in the molar ratio of 1:1:12:0.2, in addition to small amounts of peptide moiety. Methylation analysis, carbon-13 nuclear magnetic resonance and enzymic degradation studies indicated that its structural features include mainly both alpha-1,5-linked L-arabino-beta-3,6-branched D-galactan type and alpha-4,6-branched D-glucan type structural units. The influence of degradation with alpha-amylase followed by the elimination of glucan side chains on its immunological activity was discussed.  相似文献   

8.
Fractionation of the polysacchride complex of the inflorescences of pineapple weed has given a galacturonan and a pectic acid. The structures of the galacturonan and pectic acid have been studied by the methods of enzymatic hydrolysis, periodate oxidation, and exhaustive methylation. It has been established that the galacturonan is a linear polysaccharide consisting of D-galacturonic acid residues in the pyranose form with α-1→4-bonds. The main polysaccharide chain of the pectic acid consists of D-galacturonic acid residues in the pyranose form, D-galactose, L-arbinose, and D-xylose residues are covalently bound to carbon atoms 2 or 3 of the main chain of the polysaccharide.  相似文献   

9.
High-performance anion-exchange chromatography under alkaline conditions with pulsed amperometric detection was applied to the analyses of (1----2)-, (1----3)-, (1----4)- and (1----6)-linked homogeneous alpha- or beta-D-gluco-oligosaccharides and -polysaccharides up to a degree of polymerization (DP) of greater than or equal to 50. Each series of homogeneous D-gluco-oligomers and -polymers showed a linear relationship between log k' and DP in isocratic elution using 150 mM sodium hydroxide solution containing 100 mM sodium acetate as the eluent. An effective separation of individual members of an homologous series of linear glucans was achieved using gradient elution, accomplished by maintaining the sodium hydroxide concentration at 150 mM and increasing the sodium acetate concentration during the analysis. The detector response per HCOH group in D-gluco-oligomers (DP 2-7) was almost the same.  相似文献   

10.
Fractionation of the polysacchride complex of the inflorescences of pineapple weed has given a galacturonan and a pectic acid. The structures of the galacturonan and pectic acid have been studied by the methods of enzymatic hydrolysis, periodate oxidation, and exhaustive methylation. It has been established that the galacturonan is a linear polysaccharide consisting of D-galacturonic acid residues in the pyranose form with -14-bonds. The main polysaccharide chain of the pectic acid consists of D-galacturonic acid residues in the pyranose form, D-galactose, L-arbinose, and D-xylose residues are covalently bound to carbon atoms 2 or 3 of the main chain of the polysaccharide.I. P. Pavlov Medical Institute, Ryazan'. Translated from Khimiya Prirodnykh Soedinenii, No. 4, pp. 481–486, July–August, 1985.  相似文献   

11.
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   

12.
A polysaccharide has been isolated from the leaves ofPhytolacca americana and has been characterized. It has been established that it contains residues of galactose, arabinose, xylose, and rhamnose, in a ratio of 3:4:1:3 and also D-galacturonic acid (85–90%). The results obtained permit the polysaccharide to be assigned to the class of pectin substances.All-Union Oncologic Scientific Center, Academy of Medical Sciences of the USSR, Moscow. Translated from Khimiya Prirodnykh Soedinenii, No. 2, pp. 166–169, March–April, 1982.  相似文献   

13.
Summary 1. A polysaccharide has been isolated from the leaves ofPlantage major L. and its monosaccharide composition has been studied.2. It has been established that the polysaccharide investigated contains D-galacturonic acid, D-galactose, D-glucose, D-xylose, L-rhamnose, L-arabinose, a partially methylated galactose, and two unidentified monosaccharides.3. The high content of galacturonic residues (68%) in the polysaccharide enables it to be classified as a pectin.Khimiya Prirodnykh Soedinenii, Vol. 1, No. 5, pp. 297–302, 1965  相似文献   

14.
A mucilage, designated as MSL-M, was isolated from the leaves of Malva sylvestris L. var. mauritiana Mill. It was homogeneous on electrophoresis and gel chromatography. Its intrinsic viscosity value in aqueous solution was 12.0, and its molecular weight was estimated to be about 6.0 x 10(6). The major constituent is an acidic polysaccharide composed of L-rhamnose: D-galactose: D-galacturonic acid: D-glucuronic acid in the molar ratio of 6:3:2:2. Methylation analysis of both the mucilage and the carboxyl-reduced derivative, carbon-13 nuclear magnetic resonance and partial hydrolysis studies indicated its main structural features. It has considerable anti-complementary activity.  相似文献   

15.
具有免疫促进作用的螺旋藻多糖SP-4的研究   总被引:5,自引:0,他引:5  
从螺旋藻NaHCO3热水提取液中.得到四种多糖SP-1、SP-2、SP-3和SP-4,糖含量比为30:12:16:100.体外活性试验表明SP-4能促进T淋巴细胞的增殖.纸层析和高压液相色谱分析结果表明SP-4由L-鼠李糖、L-岩藻糖、L-阿拉伯糖、D-葡萄糖、D-葡萄糖胺和D-半乳糖醛酸组成,其摩尔比为4.94:2.99:2.96:1.00:1.26:2.33。IR光谱示848cm-1有明显的吸收峰,1HNMR分析在δ5.26附近有多个峰,过碘酸盐氧化和Smith降解表明SP-4分子中含有α(1→3)和α(1→4)糖苷键.  相似文献   

16.
A novel acidic polysaccharide, designated as MVS-VI, was isolated from the seeds of Malva verticillata L. It was homogeneous on electrophoresis and gel chromatography, and its molecular mass was estimated to be 26000. It is composed of L-arabinose: D-xylose: D-galactose: D-glucose: L-rhamnose: D-galacturonic acid in the molar ratio of 30: 15: 20: 3: 2: 10, in addition to small amounts of peptide moiety. Methylation analysis, carbon-13 nuclear magnetic resonance and periodate oxidation studies indicated its structural features to have mainly acidic alpha-arabino-3,6-beta-galactan type structural units. MVS-VI showed significant reticuloendothelial system-potentiating activity in a carbon clearance test, and it possesses remarkable anti-complementary activity.  相似文献   

17.
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   

18.
Conclusions 1. A polysaccharide has been isolated from the inflorescences ofMatricaria chamomilla L. It has been established that it is composed of D-galacturonic acid (45%), D-galactose (12.2%), D-glucose (2.3%), L-rhamnose (5.3%), L-arabinose (10.2%), and D-xylose (20.8%).2. The information obtained permits the polysaccharide of the camomile to be assigned to the class of pectin substances.Academician I. P. Pavlov Ryazan' State Medical Institute. Translated from Khimiya Prirodnykh Soedinenii, No. 2, pp. 137–141, March–April, 1974.  相似文献   

19.
ABSTRACT

Glycosylation of the D-galacturonic acid ester derivatives 15 and 17, which are prepared directly from D-galacturonic acid, with the thioglycosides 28 and 32, derived from the same sugar, provides α(1→4)-linked dimers. The formation of the glycosidic linkage between the galacturonic acid moieties is best achieved by iodonium di-sym-collidine perchlorate promotion. Thus, the 4'-O-p-methoxybenzyl dimer 38 can be obtained in 64% yield. Partial deprotection of the 4'-O-position provided the glycosyl acceptor 36, which was coupled with the donor 32 to yield the α(1”→4')-linked trimer 39 (48%). Approximately 8% of the β(1”→4')-coupled isomer was observed in the 13C NMR spectrum of the reaction mixture.  相似文献   

20.
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   

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