Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “POLYSACCHARIDES”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 811 records · Page 45Linked to original sources
PubMed1997

Antifibrotic effects of a polysaccharide extracted from Ganoderma lucidum, glycyrrhizin, and pentoxifylline in rats with cirrhosis induced by biliary obstruction.

For the past few years, we have been investigating polysaccharides from Ganoderma lucidum as antifibrotic agents. In a previous study, we discovered that polysaccharides extracted from G. Iucidum lowered the collagen content in liver but had no effect on serum biochemical parameters in rats subjected to bile duct ligation and scission-induced fibrosis. In this study, we changed the extraction method and obtained polysaccharides extracted from G. Iucidum. The polysaccharide from G. Iucidum reduced the serum aspartate transaminase (AST), alanine transaminase (ALT), alkaline phosphatase (ALP) and total bilirubin and also reduced the collagen content in liver and improved the morphology. Pentoxifylline, which is reported to exhibit an antifibrotic effect in pigs with fibrosis induced by yellow phosphorus, did not have any antifibrotic effects in fibrosis induced by biliary obstruction. Glycyrrhizin, which is used in the treatment of hepatitis, reduced serum ALT and AST values but there was no significance. It had no effect on liver hydroxyproline content which implies that glycyrrhizin has no antifibrotic effect in the rats with fibrosis induced by bile duct ligation and scission. These data suggest that the polysaccharide from Ganoderma lucidum could be a promising antifibrotic agent. However, further study is needed to understand the inhibition mechanism of collagen deposition of polysaccharides from Ganoderma Iucidum and its clinical applicability remains to be established.

Animals↗
PubMed1993

Antitumor protein-containing polysaccharides from a Chinese mushroom Fengweigu or Houbitake, Pleurotus sajor-caju (Fr.) Sings.

Protein-containing polysaccharides extracted from fruiting bodies of a Chinese fungus named Feng Wei Gu, were fractionated and purified, and their antitumor activities were tested, out of which the following active fractions were obtained. FIo-a: A protein-containing xyloglucan, MW 280,000, polysaccharide: protein = 76:24 (w/w), polysaccharide consisting of Man:Gal:Xyl:Glc = 2:12:42:42 (molar ratio). [alpha]D23 + 25.3 degrees. FA-2: A protein-containing mannogalactan, MW 120,000, polysaccharide: protein = 76:16 (w/w), consisting of Xyl:Man:Gal = 9:35:56 (molar ratio), [alpha]D23 + 98.5 degrees. FII-1: A Protein-containing xylan (62:21 w/w). MW 200,000, [alpha]D23 + 8.7 degrees. FIII-1a: A protein-containing glucoxylan (15:71 w/w), [alpha]D23 + 30.7 degrees, MW 90,000, consisting of Glc:Xyl = 40:44 (molar ratio). FIII-2a: A protein-containing xyloglucan, MW 70,000, polysaccharide:protein = 69:3 (w/w), polysaccharide consisting of Xyl:Glc = 36:62 (molar ratio). [alpha]D23 + 38.6 degrees.

Animals↗
PubMed1996

Antitumor activity and chemical modification of polysaccharides from niohshimeji mushroom, Tricholma giganteum.

Two chemical modification procedures, Smith degradation and formolysis processes, were used in an attempt to improve the antitumor activity of water-soluble and water-insoluble polysaccharides prepared from the fruiting body of niohshimeji, Tricholoma giganteum. The chemically modified products were examined for their antitumor effects on Sarcoma 180 solid tumor implanted in mice. The following results were as follows: Some Smith degradation products, i.e., O-R-Flo-c-beta and O-R-FA-2 prepared from water-soluble polysaccharides, and O-R-FII-1 and O-R-FIII-2-c from water-insoluble polysaccharides, had higher antitumor activities than the original polysaccharides. None of the formolysis products, F-Flo-a, F-W-Flo-a, F-FA-3, F-W-FA-3 from water-soluble polysaccharides, and F-FII-2, F-W-FII-2, F-FIII-2-b, and F-W-FIII-2-b prepared from water-insoluble polysaccharides had improved antitumor activities.

Animals↗
PubMed2002

Purification and characterization of a novel polysaccharide involved in the pellicle produced by a thermotolerant Acetobacter strain.

Acetobacter strains able to produce a thick pellicle at 37 degrees C were screened among many thermotolerant strains isolated from fruits in Thailand. As a result, Acetobacter sp. SKU 1100 was selected as the producer of a relatively thick pellicle even when cultured at higher temperatures such as 37 degrees C or 40 degrees C. This strain could produce a pellicle polysaccharide in a shaking submerged culture as well as under static culture conditions. The polysaccharide was found to be attached to the bacterial cells. Although the polysaccharide production was higher at 30 degrees C than at 37 degrees C in shaking submerged culture, the productivity in static culture was not decreased even at higher temperatures. The membrane-attached polysaccharide was purified from the SKU 1100 strain by cell disruptions using either ultrasonic treatment or lysozyme treatment, followed by ultracentrifugation, enzyme treatments, dialysis against SDS, DEAE-cellulose column chromatography, alcohol precipitation, and gel filtration chromatography. The polysaccharide purified by the sonic treatment and also by the mild conditions using lysozyme treatment had the same average molecular mass of 120 kDa. The purified polysaccharide was composed of three different monosaccharides; glucose, galactose, and rhamnose, in an approximately equimolar ratio of 1:1:1.

Acetobacter↗
PubMed1999

Prion rods contain an inert polysaccharide scaffold.

A polysaccharide consisting of mainly 1,4-linked glucose units was found associated with prion rods, which are composed mainly of insoluble aggregates of the N-terminally truncated prion protein (PrP 27-30) exhibiting the ultrastructural and tinctorial properties of amyloid. The polysaccharide differs in composition from the Asn-linked oligosaccharides and the GPI-anchor of the prion protein. Prion rods were prepared from scrapie-infected hamster brains using two different purification protocols. Prolonged digestion of rods with proteinase K reduced PrP by a factor of at least 500, leaving about 10% (w/w) of the sample as an insoluble remnant. Only glucose was obtained by acid hydrolysis of the remnant and methylation analysis showed 80% 1,4-, 15% 1,6- and 5% 1,4,6-linked glucose units. The physical and chemical properties as well as the absence of terminal glucose units indicate a very high molecular mass of the polysaccharide. No evidence was found for covalent bonds between PrP and the polysaccharide. The polysaccharide certainly contributes to the unusual chemical and physical stability of prion rods, acting like a scaffold. A potential structural and/or functional relevance of the polysaccharide scaffold is discussed.

Animals↗
PubMed1985

[Histochemical demonstration of proteins, lipids and polysaccharides in Japanese monkey oocytes].

A histochemical study of proteins, lipids and polysaccharides was carried out in the oocytes of Japanese monkey (Macaca fuscata) during development of follicles. There were a small number of protein granules reactive to acrolein-Schiff in the cytoplasm of oocytes from primordial, secondary and vesicular follicles, while there were no lipid droplets, granules of neutral polysaccharides or acid polysaccharides in the cytoplasm. Proteins reactive to acrolein-Schiff, neutral polysaccharides reactive to periodic acid-Schiff and acid polysaccharides stainable with alcian blue were observed in the zona pellucida of the oocytes of secondary and vesicular follicles. The zona pellucida contained sudanophilic lipids composed of neutral fats and lipoids, besides the proteins and polysaccharides.

Animals↗
PubMed1996

Current applications of polysaccharides in colon targeting.

Polysaccharides have over the years been used widely in pharmaceutical, chemical, and biochemical drug delivery. This family of natural polymers has an appeal to the area of drug delivery as it is comprised of polymers with a large number of derivatizable groups, a wide range of molecular weights, varying chemical compositions, and for the most part, a low toxicity and biodegradability, yet a high stability. The main scope of this review is to relate the polysaccharides available now to the rapidly growing field of colonic drug delivery. Polysaccharides have been applied to the area as controlled release coatings, matrices, macromolecular carriers, and biodegradable carriers. Bacterial sources of polysaccharidases as well as a detailed treatise of the enzymatic flora of the colonic region are discussed, followed by a presentation of the polysaccharides available for the purpose of colon-specific drug delivery. A final overview of the various approaches to obtain colon-specific delivery by using polysaccharides and a summary of available in vitro and in vivo testing methods will lead to the conclusion that polysaccharides at this point appear to be very promising compounds for use in obtaining colon-specific drug delivery systems.

Animals↗
PubMed2005

Sulfated polysaccharides derived from dietary seaweeds increase the esterase activity of a lymphocyte tryptase, granzyme A.

Intake of sulfated polysaccharides, such as fucoidan or lambda-carrageenan extracted from seaweeds, has been shown to enhance immune responses, resulting in inhibition of tumor growth. However, little is known about the mechanisms by which these sulfated compounds mediate the enhancement. In the present study, we examined the effect of sulfated polysaccharides from seaweeds on esterase activity of a lymphocyte tryptase, granzyme A (GzmA), which is believed to induce the production of cytokines in a variety of cells. Inclusion of fucoidan (from Fucus vesiculosus) or lambda-carrageenan (from Gigartina aciculaire and Gigartina) in the reaction mixture increased the hydrolysis of Nalpha-benzyloxy-L-lysine thiobenzyl ester (BLT) by a recombinant rat GzmA in a concentration-dependent manner. Heparin, a sulfated polysaccharide from animal tissues, also increase the BLT hydrolysis, but the effect was less remarkable than those of the polysaccharides from the seaweeds. Hanes-Woolf analysis revealed that the enhancements in the presence of these sulfated compounds from the seaweeds were attributed to the increases in the affinity of the enzyme toward the substrate but not to those in the turnover rate. Chondroitin sulfate A, a sulfated polysaccharide found in animal and plant tissues, showed no positive effect on the hydrolysis. In the present paper, we propose that the enhancement of immune responses by intake of the sulfated polysaccharides from seaweeds can be partially accounted for by their direct effects on GzmA.

Animals↗
PubMed2003

[Effects of polysaccharides of Cryptoporus volvatus on bronchial hyperreasponsiveness and inflammatory cells in ovalbumin sensitized rats].

OBJECTIVE: To study the effects of polysaccharides of cultured Cryptoporus volvatus(CVPS) on airway hyperresponsiveness of ovalbumin-sensitized rats and to evaluate their mechanisms. METHODS: Polysaccharides A, B (5mg/kg, 20mg/kg) and ketotifen(5mg/kg) or vehicle(same volume of saline) were administrated orally for 10 days in ovalbumin -sensitized rats, methacholine bronchial provocation tests were performed to determine airway hyperresponsiveness. Bronchoalveolar lavage fluid (BALF) and peritoneal lavage fluid were prepared after the animals were challenged by nebulized antigen. The differential white cell count in BALF,and the degranulated mast cell count as well as differential white cell count in peritoneal lavage fluid were performed. RESULT: Polysaccharides markedly inhibited the increased lung resistance and the decreased lung compliance induced by antigen challenge,significantly reduced total cell counts and absolute eosinophil counts in BALF(P<0.05); polysaccharides B was more effective than polysaccharides A. They also inhibited recruitment of inflammatory cells in peritoneal lavage fluid and inhibited the allergen-induced mast cell degranulation. CONCLUSION: Polysaccharides of CVPS inhibit airway hyperresponsiveness by stabilizing mast cell membranes and reducing infiltration and chemotaxis of eosinophils and may be developed as a potential anti-asthmatic drug.

Animals↗
PubMed1976

The influence of borate and calcium on the gel formation of a sulfated polysaccharide from Ulva lactuca.

The water-soluble, sulfated polysaccharide isolated from Ulva lactuca, forms a soft gel when dialysed against sea-water, provided the polysaccharide concentration is 1% or higher and the pH above 7.5. The components of sea-water needed for this gel formation are boric acid and calcium ions. At concentration normally found in sea-water, neither borate nor calcium ions alone produce a gel. It is assumed that the gel formation involves the formation of borate-polysaccharide complexes leading to intermolecular linkages which are stabilized by calcium ions in an unknown manner. This assumption is supported by experiments with extraction of this polysaccharide from the dry seaweed and by the results obtained with the isolated polysaccharide. Agreement between these experiments leads to the conclusion that the sulfated polysaccharide (in vivo) most probably occurs as a gel stabilized by the borate and calcium ions in sea-water.

Borates↗
PubMed1998

Degradation of pectic polysaccharides in pickled green olives.

The changes that occur in the pectic fractions in the cell wall of olives of the Manzanilla variety (Olea europaea pomiformis) during processing (initial treatment at high pH and subsequent lactic fermentation) have been researched. After studying various conditions for fractionating the pectic polysaccharides, the most adequate were chosen, involving sequential extraction with water, imidazole-hydrochloric acid buffer, sodium carbonate, 1 M potassium hydroxide, and 4 M potassium hydroxide. In the unprocessed fruit, the fractions studied consist mainly of high-molecular-weight acidic polysaccharides (70 to 250 kDa): homogalacturonans, rhamnogalacturonans, and branched arabinans. These were found in different proportions depending on the extraction agent used. At the same time, significant amounts of relatively low-molecular-weight (10 to 10.5 kDa) neutral branched arabinans were found in the water-soluble fraction. As a result of the processing, changes occurred in the proportions of the different groups of polysaccharides in accordance with changes in their solubility characteristics. These changes were reflected in the processed fruit by (i) and increase in the neutral branched arabinans in the water-soluble fraction due to the increased presence of such polysaccharides originally found in the carbonate and 4 M KOH-soluble fractions; (ii) an increase in homogalacturonans and rhamnogalacturonans, without significant changes in molecular weights, in the imidazole-soluble fraction as a result of the increased presence of corresponding polysaccharides originally found in the carbonate-soluble and water-soluble fractions; (iii) a substantial increase in uronic acids in the 1 M potassium hydroxide-soluble fraction, preferentially as low-molecular-weight polysaccharides; and (iv) a solubilization of arabinans in the 4 M potassium hydroxide-soluble fraction.

Cell Wall↗
PubMed1998

Degradation of hemicellulosic and cellulosic polysaccharides in pickled green olives.

Changes that take place in the hemicellulosic and cellulosic polysaccharide fractions of the cell wall of olives (Olea europaea pomiformis, Manzanilla variety) during "Spanish style" processing have been studied. A comparative study of the extraction of hemicellulosic polysaccharides with and without prior delignification showed that these compounds could be extracted without previous delignification of the cell wall material. The depectinated material was sequentially extracted with 1 M and 4 M potassium hydroxide. In the unprocessed fruit, the neutral polysaccharides of the 1 M potassium hydroxide-soluble fraction contained mainly xyloglucans with significant amounts of arabinans. In the 4 M potassium hydroxide-soluble fraction, xyloglucans were the most important polysaccharide. The apparent molecular weight of these polysaccharides was 40 to 250 kDa. In addition, hemicelluloses (xylans and xyloglucans), which it was not possible to isolate in the previous stages of fractionation, were also found to be closely linked to the cellulose fraction. The most important changes during processing were the decrease in the molecular weight of xyloglucans in the 4 M potassium hydroxide-soluble fraction and the substantial decrease in the cellulose fraction, which in quantitative terms was one of the largest decreases that took place in the components of the total cell wall polysaccharides.

Cellulose↗
PubMed1979

Acetylated methylmannose polysaccharide of Streptomyces griseus. Locations of the acetyl groups.

The positions of esterification of the 4 to 5 acetyl residues in the acetylated methylmannose-containing polysaccharide from Streptomyces griseus have been established by the methyl replacement technique, wherein ester substituents are specifically replaced with methyl ether substituents. The newly incorporated methyl groups were distinguished from 3-O-methyl groups by the use of polysaccharide containing radioactively labeled endogenous methyl groups. The positions of methyl group localization were established by a proton magnetic resonance study of the intact methyl-replaced polysaccharide combined with an analysis of the constituent monosaccharides by gas-liquid chromatography-electron impact mass spectrometry of their alditol acetate derivatives. These studies demonstrate that the acetyl groups are located at position 6 of approximately half of the 10 contiguous alpha(1 leads to 4)-linked 3-O-methyl-D-mannose residues. Purification of the polysaccharide was accomplished by an added step involving affinity chromatography on a column containing immobilized palmitoyl residues. The affinity of the polysaccharide for this long chain lipid suggests that its plays a role similar to the methylmannose-containing polysaccharide of Mycobacterium smegmatis in its regulation of the bacterium's fatty acid synthetase.

Acetylation↗
PubMed2000

Soluble polysaccharide and biomass of red microalga Porphyridium sp. alter intestinal morphology and reduce serum cholesterol in rats.

The present study investigated the effects of the red microalga Porphyridium sp. on gastrointestinal physiology and lipid metabolism in male Sprague-Dawley rats. Diets containing dietary fibre from pelleted red microalgal cells (biomass) or their sulfated polysaccharide, pectin or cellulose (control) were fed to rats for a period of 30 d. All three fibre-supplemented diets increased the length of both the small intestine and colon, with a significantly greater effect in rats fed the algal polysaccharide. The polysaccharide also increased mucosa and muscularis cross-sectional area of the jejunum, and caused hypertrophy in the muscularis layer. The algal biomass significantly lowered gastrointestinal transit time by 44% in comparison with the control rats. Serum and mucosal cholecystokinin levels were lower in rats on the pectin and polysaccharide diets, while cholecystokinin levels in rats fed algal biomass were not different from those in the control animals. In comparison with the control diet, all the experimental diets significantly lowered serum cholesterol levels (22-29%). Feeding of non-fermentable algal polysaccharide or biomass significantly increased faecal weight and bile acid excretion compared with pectin-fed or control rats. The algal polysaccharide and biomass were thus shown to be potent hypocholesterolaemic agents active at low concentrations in the diet. Both metabolic and morphological changes were observed following consumption of algae, suggesting several possible mechanisms by which the alga affects lipid metabolism. The results presented in the present study encourage the use of red microalga as a functional food.

Analysis of Variance↗
PubMed2001

[Modulation of angelica sinensis polysaccharides on the expression of nitric oxide synthase and Bax, Bcl-2 in liver of immunological liver-injured mice].

OBJECTIVE: To investigate the modulation of Angelica Sinensis Polysaccharides on the expression of nitric oxide synthase and Bax, Bcl-2 in the liver of immunological liver injured mice. METHODS: Immunological liver injury was induced by lipopolysaccharide (ip, 2mug/10g) in bacillus calmette-guerin (ip, 1mg/10g, qd/1 d) primed mice. Angelica Sinensis Polysaccharides was administrated to the mice with 30mg/kg, 60mg/kg, respectively. The effects of Angelica Sinensis Polysaccharides on the expression of nitric oxide synthase, Bcl-2, and Bax gene were assessed by immunohistochemistry, and the nitric oxide (NO) production, alanine transaminase (ALT) activity, glutathione S-transferase (GST) activity in serum were determined. RESULTS: The levels of NO, sALT, and sGST were significantly higher in immunological liver-injured mice than controls. The contents of iNOS and Bax were 17.8 times (P<0.001) and 1.31 times (P<0.05) of control values, respectively. cNOS expression was not obviously changed, and no Bcl-2 expression was found in immunological liver-injured mice. Angelica Sinensis Polysaccharides of 30mg/kg could reduce the levels of NO, sALT, and sGST by 24.6%, 40.8%, and 18.4%, respectively; the expression of iNOS and Bax decrease by 84.2% and 37.1%; and the expression of cNOS, Bcl-2 increase by 66.8% and 3.38 times, respectively. The influence of Angelica Sinensis Polysaccharides of 60mg/kg was not so obvious as that of 30mg/kg on sGST, NO, cNOS, Bax, and Bcl-2, but was more effective on sALT and iNOS. CONCLUSIONS: NO production may play a role in the LPS-induced hepatotoxicity. Angelica Sinensis Polysaccharides can alleviate the immune liver injury by modulating the expression of cNOS, iNOS, Bax, Bcl-2.

Angelica sinensis↗
PubMed1975

[An intracellular polysaccharide involved in sporulation of "Clostridium butyricum" I. Cytology, production and preliminary enzymic analysis (author's transl)].

Free glucose concentration and polysaccharide production in Clostridium butyricum cells have been studied with an enzymatic method. Results indicated a substantial decrease in intracellular glucose content simultaneously with a production of polysaccharide prior to the end of exponential growth. Then the polysaccharide accumulated rapidly to reach a maximum just before the first refractile spores appeared, and it decreased by 50% during the last stages (V and VI) of sproulation. Electron micrographs of ultrathin sections have demonstrated that most of the polysaccharide is located inside the mother cell cytoplasm as large granules when the remaining is dispersed within the spore cytoplasm beginning during stage III of the sporulation. Overall results showed that production and use of C. butyricum polysaccharide were closely related to sporulation. The isolated polysaccharide exhibited poor water solubility, iodine spectrum with a lambda max at 545 nm and 72% beta-amylolysis. Total hydrolysis occurred with amyloglucosidase indicating an alpha-glucan containing alpha(1 leads to 4) and alpha(1 leads to 6) glucose linkages. The debranching from its beta-dextrin limit by pullulanase revealed the presence of a glycogen like-type structure with some external chains which are longer than those of a normal glycogen. This glycogen arrangement appeared to be of clusters linked by linear chains at least as long as the longest external chains.

Clostridium↗
PubMed2001

[Effects of medium and culture conditions on polysaccharide synthesis by suspension cell culture of Gardenia jasminoides Eills].

The effects of medium and culture condition on polysaccharide synthesis by suspension culture of Gardenia jasminoides Eills were studied. The results show that B5 was the optimum medium, 5-10 days was suitable for subculture periods, and an inoculum of 80 g/L wet cell was better to cell growth and polysaccharide accumulation. For carbon source, it was better to use glucose than sucrose on cell growth, but due to the higher price of glucose, 45 g/L compound carbon source combined sucrose with glucose (1:1) was the optimum. The effect of different kinds of nitrogen source on cell growth and polysaccharide synthesis was not so big, and 40-50 mmol/L nitrogen was optimum, lower concentration of nitrogen source could inhibit the synthesis of polysaccharides. In addition, by controlling the harvest time of the polysaccharide in the suspension culture, the accumulation of yellow pigment could be prevented, which is easier to the polysaccharide purification.

Cell Count↗
PubMedDate not supplied

[Comparative characterization of polysaccharide fractions in grapes].

Different methods of isolating polysaccharides from grapes were evaluated with respect to the three indictrial grape varieties Traminer pink, Rkatsiteli, Cabernet-Sovinjon. Hot water extration was shown to be the best method in the isolation of water-soluble polysaccharides in primary wine-making. The qualitative and quantitative composition of the isolated polysaccharides was found to depend on the method of isolating polysaccharide fractions. The polysaccharides of grapes were heterogeneous in their molecular weight. The results of periodate oxidation of high molecular weight carbohydrates suggest a branched structure of polymers of water-soluble polysaccharides of grapes.

Fruit↗