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Sample records for 0f bacterial polysaccharide

  1. Polysaccharides and bacterial plugging

    Energy Technology Data Exchange (ETDEWEB)

    Fogler, H.S.

    1991-11-01

    Before any successful application of Microbial Enhanced Oil Recovery process can be realized, an understanding of the cells' transport and retentive mechanisms in porous media is needed. Cell transport differs from particle transport in their ability to produce polysaccharides, which are used by cells to adhere to surfaces. Cell injection experiments have been conducted using Leuconostoc cells to illustrate the importance of cellular polysaccharide production as a transport mechanism that hinders cell movement and plugs porous media. Kinetic studies of the Leuconostoc cells, carried out to further understand the plugging rates of porous media, have shown that the cells' growth rates are approximately equal when provided with monosaccharide (glucose and fructose) or sucrose. The only difference in cell metabolism is the production of dextran when sucrose is supplied as a carbon source. Experimentally it has also been shown that the cells' growth rate is weakly dependent upon the sucrose concentration in the media, and strongly dependent upon the concentration of yeast extract. The synthesis of cellular dextran has been found to lag behind cell generation, thus indicating that the cells need to reach maturity before they are capable of expressing the detransucrase enzyme and synthesizing insoluble dextran. Dextran yields were found to be dependent upon the sucrose concentration in the media. 10 refs., 9 figs., 9 tabs.

  2. Remodeling bacterial polysaccharides by metabolic pathway engineering

    OpenAIRE

    Yi, Wen; Liu, Xianwei; Li, Yanhong; Li, Jianjun; Xia, Chengfeng; Zhou, Guangyan; Zhang, Wenpeng; Zhao, Wei; Chen, Xi; Wang, Peng George

    2009-01-01

    Introducing structural modifications into biomolecules represents a powerful approach to dissect their functions and roles in biological processes. Bacterial polysaccharides, despite their rich structural information and essential roles in bacterium-host interactions and bacterial virulence, have largely been unexplored for in vivo structural modifications. In this study, we demonstrate the incorporation of a panel of monosaccharide analogs into bacterial polysaccharides in a highly homogenou...

  3. Bacterial Extracellular Polysaccharides Involved in Biofilm Formation

    Directory of Open Access Journals (Sweden)

    Elena P. Ivanova

    2009-07-01

    Full Text Available Extracellular polymeric substances (EPS produced by microorganisms are a complex mixture of biopolymers primarily consisting of polysaccharides, as well as proteins, nucleic acids, lipids and humic substances. EPS make up the intercellular space of microbial aggregates and form the structure and architecture of the biofilm matrix. The key functions of EPS comprise the mediation of the initial attachment of cells to different substrata and protection against environmental stress and dehydration. The aim of this review is to present a summary of the current status of the research into the role of EPS in bacterial attachment followed by biofilm formation. The latter has a profound impact on an array of biomedical, biotechnology and industrial fields including pharmaceutical and surgical applications, food engineering, bioremediation and biohydrometallurgy. The diverse structural variations of EPS produced by bacteria of different taxonomic lineages, together with examples of biotechnological applications, are discussed. Finally, a range of novel techniques that can be used in studies involving biofilm-specific polysaccharides is discussed.

  4. Recombinant plants provide a new approach to the production of bacterial polysaccharide for vaccines.

    Directory of Open Access Journals (Sweden)

    Claire M Smith

    Full Text Available Bacterial polysaccharides have numerous clinical or industrial uses. Recombinant plants could offer the possibility of producing bacterial polysaccharides on a large scale and free of contaminating bacterial toxins and antigens. We investigated the feasibility of this proposal by cloning and expressing the gene for the type 3 synthase (cps3S of Streptococcus pneumoniae in Nicotinia tabacum, using the pCambia2301 vector and Agrobacterium tumefaciens-mediated gene transfer. In planta the recombinant synthase polymerised plant-derived UDP-glucose and UDP-glucuronic acid to form type 3 polysaccharide. Expression of the cps3S gene was detected by RT-PCR and production of the pneumococcal polysaccharide was detected in tobacco leaf extracts by double immunodiffusion, Western blotting and high-voltage paper electrophoresis. Because it is used a component of anti-pneumococcal vaccines, the immunogenicity of the plant-derived type 3 polysaccharide was tested. Mice immunised with extracts from recombinant plants were protected from challenge with a lethal dose of pneumococci in a model of pneumonia and the immunised mice had significantly elevated levels of serum anti-pneumococcal polysaccharide antibodies. This study provides the proof of the principle that bacterial polysaccharide can be successfully synthesised in plants and that these recombinant polysaccharides could be used as vaccines to protect against life-threatening infections.

  5. Improved coupling of bacterial polysaccharides to macromolecules and solid supports

    DEFF Research Database (Denmark)

    2013-01-01

    The invention relates to a method of producing a polysaccharide-carrier conjugate comprising coupling a polysaccharide to a carrier, said polysaccharide comprising at least one monosaccharide unit comprising a keto-carboxy group according to the formula -C(=O)COOR, where R is either hydrogen or C1......-alkoxyamine group of the carrier with a keto-carboxy group of said polysaccharide to form a covalent amide bond between the carrier and the polysaccharide. Another aspect of the present invention relates to a compound or solid surface obtained when performing the method of the present invention. A third aspect...

  6. Human tandem-repeat-type galectins bind bacterial non-βGal polysaccharides

    DEFF Research Database (Denmark)

    Knirel, Yu A.; Gabius, H.-J.; Blixt, Klas Ola;

    2014-01-01

    ), prompted us to establish an array with bacterial polysaccharides. We addressed the question whether sugar determinants other than β-galactosides may be docking sites, using human galectins-4, -8, and -9. Positive controls with histo-blood group ABH-epitopes and the E. coli 086 polysaccharide ascertained...... the suitability of the set-up. Significant signal generation, depending on type of galectin and polysacchride, was obtained. Presence of cognate β-galactoside-related epitopes within a polysaccharide chain or its branch will not automatically establish binding properties, and structural constellations lacking...

  7. POLYSACCHARIDES AND eDNA AID BACTERIAL ATTACHMENT TO POLYMER BRUSH COATINGS (PLL-g-PEG)

    DEFF Research Database (Denmark)

    Zeng, Guanghong; Ogaki, Ryosuke; Regina, Viduthalai R.;

    in complete absence of bacterial colonization from Pseudomonas aeruginosa, Staphylococcus aureus and Staphylococcus epidermis, whereas the conventional PLL-g-PEG coatings only resisted colonization by P. aeruginosa and S. aureus, but not S. epidermidis. Colonization patterns were also reflected in single...... of the conventional coating. These results explain why S. epidermidis, which produces polysaccharides and extracellular DNA, could successfully colonize the conventional PLL-g-PEG coatings. The ability of high-density PLL-g-PEG to resist polysaccharides, DNA, and bacterial adhesion of all strains is thus highly...

  8. Polysaccharides enriched in rare sugars: bacterial sources, production and applications

    Directory of Open Access Journals (Sweden)

    Christophe eRoca

    2015-04-01

    Full Text Available Microbial extracellular polysaccharides (EPS, produced by a wide range of bacteria, are high molecular weight biopolymers, presenting an extreme diversity in terms of chemical structure and composition. They may be used in many applications, depending on their chemical and physical properties. A rather unexplored aspect is the presence of rare sugars in the composition of some EPS. Rare sugars, such as rhamnose or fucose, may provide EPS with additional biological properties compared to those composed of more common sugar monomers.This review gives a brief overview of these specific EPS and their producing bacteria. Cultivation conditions are summarized, demonstrating their impact on the EPS composition, together with downstream processing. Finally, their use in different areas, including cosmetics, food products, pharmaceuticals and biomedical applications, are discussed.

  9. Polysaccharides and bacterial plugging. Final report, 1992--1993

    Energy Technology Data Exchange (ETDEWEB)

    Fogler, H.S.

    1995-02-01

    In situ core plugging experiments and transport experiments, using the model bacteria Leuconostoc m., have been conducted. Results demonstrated that cellular polysaccharide production increases cell distribution in porous media and caused an overall decrease in media permeability. Further, a parallel core plugging experiment was conducted and showed the feasibility of this system to divert injection fluid from high permeability zones into low permeability zones within porous media as is needed for profile modification. To implement this type of application, however, controlled placement of cells and rates of polymer production are needed. Therefore, kinetic studies were performed. A kinetic model was subsequently developed for Leuconostoc m. bacteria. This model is based on data generated from batch growth experiments and allows for the prediction of saccharide utilization, cell generation, and dextran production. These predictions can be used to develop injection strategies for field implementation. Transport and in situ growth micromodel experiments have shown how dextran allow cells to remain as clusters after cell division which enhanced cell capture and retention in porous media. Additional Damkohler experiments have been performed to determine the effects of the nutrient injection rate and nutrient concentration on the rate of porous media plugging. As shown experimentally and as predicted by a model for in situ growth, an increase in nutrient concentration and/or its injection rate will result in a faster rate of porous media plugging. Through continuum model simulations, it has been shown that the initial cell profiles play a key role on the core plugging rate. Controlling the location of the inoculating cells is thus another key factor in using bacteria for profile modification.

  10. Polysaccharides and bacterial plugging. [Progress report], October 1--December 31, 1992

    Energy Technology Data Exchange (ETDEWEB)

    Fogler, H.S.

    1992-12-31

    The objectives of this research are to elucidate and model bacterial transport in porous media, to determine the importance of polysaccharides bridging as a retentive mechanism, and to identify key parameters that influence porous media plugging. A continuum core plugging model is being development. This model will include the resulting cell, polysaccharide, and nutrient profiles as growth occurs with time. Initial cell profiles were found to be needed for the model. Experiments and a cell retainment model has been completed to predict cell profiles for a high permeability cores. The continuum model starts with applying a mass balance to an elemental volume of porous media and makes the assumptions that: cells once deposited remain sessile; polymer and enzyme remain in location of cells; neglect dispersion and diffusion in model; neglect yeast extract balance, and neglect changes in the interstitial velocity.

  11. Polysaccharide Capsule and Sialic Acid-Mediated Regulation Promote Biofilm-Like Intracellular Bacterial Communities during Cystitis ▿

    OpenAIRE

    Anderson, Gregory G.; Goller, Carlos C.; Justice, Sheryl; Hultgren, Scott J.; Seed, Patrick C.

    2010-01-01

    Uropathogenic Escherichia coli (UPEC) is the leading cause of urinary tract infections (UTIs). A murine UTI model has revealed an infection cascade whereby UPEC undergoes cycles of invasion of the bladder epithelium, intracellular proliferation in polysaccharide-containing biofilm-like masses called intracellular bacterial communities (IBC), and then dispersal into the bladder lumen to initiate further rounds of epithelial colonization and invasion. We predicted that the UPEC K1 polysaccharid...

  12. Structure, biosynthesis, and function of bacterial capsular polysaccharides synthesized by ABC transporter-dependent pathways.

    Science.gov (United States)

    Willis, Lisa M; Whitfield, Chris

    2013-08-30

    Bacterial capsules are formed primarily from long-chain polysaccharides with repeat-unit structures. A given bacterial species can produce a range of capsular polysaccharides (CPSs) with different structures and these help distinguish isolates by serotyping, as is the case with Escherichia coli K antigens. Capsules are important virulence factors for many pathogens and this review focuses on CPSs synthesized via ATP-binding cassette (ABC) transporter-dependent processes in Gram-negative bacteria. Bacteria utilizing this pathway are often associated with urinary tract infections, septicemia, and meningitis, and E. coli and Neisseria meningitidis provide well-studied examples. CPSs from ABC transporter-dependent pathways are synthesized at the cytoplasmic face of the inner membrane through the concerted action of glycosyltransferases before being exported across the inner membrane and translocated to the cell surface. A hallmark of these CPSs is a conserved reducing terminal glycolipid composed of phosphatidylglycerol and a poly-3-deoxy-d-manno-oct-2-ulosonic acid (Kdo) linker. Recent discovery of the structure of this conserved lipid terminus provides new insights into the early steps in CPS biosynthesis.

  13. Chemoenzymatic synthesis of the bacterial polysaccharide repeating unit undecaprenyl pyrophosphate and its analogs.

    Science.gov (United States)

    Li, Lei; Woodward, Robert L; Han, Weiqing; Qu, Jingyao; Song, Jing; Ma, Cheng; Wang, Peng G

    2016-07-01

    Polysaccharides are essential and immunologically relevant components of bacterial cell walls. These biomolecules can be found covalently attached to lipids (e.g., O-polysaccharide (PS) contains undecaprenyl and lipopolysaccharide (LPS) contains lipid A) or noncovalently associated with cell wells (e.g., capsular PS (CPS)). Although extensive genetic studies have indicated that the Wzy-dependent biosynthetic pathway is primarily responsible for producing such polysaccharides, in vitro biochemical studies are needed to determine, for example, which gene product is responsible for catalyzing each step in the pathway, and to reveal molecular details about the Wzx translocase, Wzy polymerase and O-PS chain-length determinant. Many of these biochemical studies require access to a structurally well-defined PS repeating unit undecaprenyl pyrophosphate (RU-PP-Und), the key building block in this pathway. We describe herein the chemoenzymatic synthesis of Escherichia coli (serotype O157) RU-PP-Und. This involves (i) chemical synthesis of precursor N-acetyl-D-galactosamine (GalNAc)-PP-Und (2 weeks) and (ii) enzymatic extension of the precursor to produce RU-PP-Und (2 weeks). Undecaprenyl phosphate and peracetylated GalNAc-1-phosphate are prepared from commercially available undecaprenol and peracetylated GalNAc. The chemical coupling of these two products, followed by structural confirmation (mass spectrometry and NMR) and deprotection, generates GalNAc-PP-Und. This compound is then sequentially modified by enzymes in the E. coli serotype O157 (E. coli O157) O-PS biosynthetic pathway. Three glycosyltransferases (GTs) are involved (WbdN, WbdO and WbdP) and they transfer glucose (Glc), L-fucose (L-Fuc) and N-acetylperosamine (PerNAc) onto GalNAc-PP-Und to form the intact RU-PP-Und in a stepwise manner. Final compounds and intermediates are confirmed by mass spectrometry. The procedure can be adapted to the synthesis of analogs with different PS or lipid moieties. PMID:27336706

  14. Structure and dynamics of a polysaccharide matrix: aqueous solutions of bacterial levan.

    Science.gov (United States)

    Benigar, Elizabeta; Dogsa, Iztok; Stopar, David; Jamnik, Andrej; Kralj Cigić, Irena; Tomšič, Matija

    2014-04-15

    The polysaccharide levan is a homopolymer of fructose and appears in nature as an important structural component of some bacterial biofilms. This paper reports the structural and dynamic properties of aqueous solutions of levan of various origin obtained from dynamic rheological, small-angle X-ray scattering, static and dynamic light scattering, as well as density and sound velocity measurements, determination of polymer branching after per-O-methylation, and microscopy. Besides samples of commercially available levan from Zymomonas mobilis and Erwinia herbicola, we also isolated, purified, and studied a levan sample from the biofilm of Bacillus subtilis. The results of dynamic rheological and light scattering measurements revealed very interesting viscoelastic properties of levan solutions even at very low polymer concentrations. The findings were complemented by small-angle X-ray scattering data that revealed some important differences in the structure of the aqueous levan solutions at the molecular level. Besides presenting detailed dynamic and structural results on the polysaccharide systems of various levans, one of the essential goals of this work was to point out the level of structural information that may be obtained for such polymer systems by combining basic physicochemical, rheological, and various light scattering techniques. PMID:24654746

  15. Bacterial capsular polysaccharide prevents the onset of asthma through T-cell activation.

    Science.gov (United States)

    Johnson, Jenny L; Jones, Mark B; Cobb, Brian A

    2015-04-01

    Over the last four decades, increases in the incidence of immune-mediated diseases in the Western world have been linked to changes in microbial exposure. It is becoming increasingly clear that the normal microbiota in the gut can profoundly alter susceptibility to a wide range of diseases, such as asthma, in which immune homeostasis is disrupted, yet the mechanisms governing this microbial influence remains poorly defined. In this study, we show that gastrointestinal exposure to PSA, a capsular polysaccharide derived from the commensal bacterium Bacteroides fragilis, significantly limits susceptibility to the induction of experimental asthma. We report that direct treatment of mice with PSA generates protection from asthma, and this effect can be given to a naïve recipient by adoptive transfer of CD4(+) T cells from PSA-exposed mice. Remarkably, we found that these PSA-induced T cells are not canonical FoxP3(+) regulatory T cells, but that they potently inhibit both Th1 and Th2 models of asthma in an IL-10-dependent fashion. These findings reveal that bacterial polysaccharides link the microbiota with the peripheral immune system by activating CD4(+)Foxp3(-) T cells upon exposure in the gut, and they facilitate resistance to unnecessary inflammatory responses via the production of IL-10. PMID:25347992

  16. Antibiofilm polysaccharides

    OpenAIRE

    Rendueles, Olaya; Kaplan, Jeffrey B.; Ghigo, Jean-Marc

    2012-01-01

    Bacterial extracellular polysaccharides have been shown to mediate many of the cell-to cell and cell-to-surface interactions that are required for the formation, cohesion and stabilization of bacterial biofilms. However, recent studies have identified several bacterial polysaccharides that inhibit biofilm formation by a wide-spectrum of bacteria and fungi both in vitro and in vivo. This review discusses the composition, modes of action, and potential biological roles of antibiofilm polysaccha...

  17. Bacteriophage Tailspikes and Bacterial O-Antigens as a Model System to Study Weak-Affinity Protein-Polysaccharide Interactions.

    Science.gov (United States)

    Kang, Yu; Gohlke, Ulrich; Engström, Olof; Hamark, Christoffer; Scheidt, Tom; Kunstmann, Sonja; Heinemann, Udo; Widmalm, Göran; Santer, Mark; Barbirz, Stefanie

    2016-07-27

    Understanding interactions of bacterial surface polysaccharides with receptor protein scaffolds is important for the development of antibiotic therapies. The corresponding protein recognition domains frequently form low-affinity complexes with polysaccharides that are difficult to address with experimental techniques due to the conformational flexibility of the polysaccharide. In this work, we studied the tailspike protein (TSP) of the bacteriophage Sf6. Sf6TSP binds and hydrolyzes the high-rhamnose, serotype Y O-antigen polysaccharide of the Gram-negative bacterium Shigella flexneri (S. flexneri) as a first step of bacteriophage infection. Spectroscopic analyses and enzymatic cleavage assays confirmed that Sf6TSP binds long stretches of this polysaccharide. Crystal structure analysis and saturation transfer difference (STD) NMR spectroscopy using an enhanced method to interpret the data permitted the detailed description of affinity contributions and flexibility in an Sf6TSP-octasaccharide complex. Dodecasaccharide fragments corresponding to three repeating units of the O-antigen in complex with Sf6TSP were studied computationally by molecular dynamics simulations. They showed that distortion away from the low-energy solution conformation found in the octasaccharide complex is necessary for ligand binding. This is in agreement with a weak-affinity functional polysaccharide-protein contact that facilitates correct placement and thus hydrolysis of the polysaccharide close to the catalytic residues. Our simulations stress that the flexibility of glycan epitopes together with a small number of specific protein contacts provide the driving force for Sf6TSP-polysaccharide complex formation in an overall weak-affinity interaction system. PMID:27045683

  18. Photorhabdus adhesion modification protein (Pam) binds extracellular polysaccharide and alters bacterial attachment

    LENUS (Irish Health Repository)

    Jones, Robert T

    2010-05-12

    Abstract Background Photorhabdus are Gram-negative nematode-symbiotic and insect-pathogenic bacteria. The species Photorhabdus asymbiotica is able to infect humans as well as insects. We investigated the secreted proteome of a clinical isolate of P. asymbiotica at different temperatures in order to identify proteins relevant to the infection of the two different hosts. Results A comparison of the proteins secreted by a clinical isolate of P. asymbiotica at simulated insect (28°C) and human (37°C) temperatures led to the identification of a small and highly abundant protein, designated Pam, that is only secreted at the lower temperature. The pam gene is present in all Photorhabdus strains tested and shows a high level of conservation across the whole genus, suggesting it is both ancestral to the genus and probably important to the biology of the bacterium. The Pam protein shows limited sequence similarity to the 13.6 kDa component of a binary toxin of Bacillus thuringiensis. Nevertheless, injection or feeding of heterologously produced Pam showed no insecticidal activity to either Galleria mellonella or Manduca sexta larvae. In bacterial colonies, Pam is associated with an extracellular polysaccharide (EPS)-like matrix, and modifies the ability of wild-type cells to attach to an artificial surface. Interestingly, Surface Plasmon Resonance (SPR) binding studies revealed that the Pam protein itself has adhesive properties. Although Pam is produced throughout insect infection, genetic knockout does not affect either insect virulence or the ability of P. luminescens to form a symbiotic association with its host nematode, Heterorhabditis bacteriophora. Conclusions We studied a highly abundant protein, Pam, which is secreted in a temperature-dependent manner in P. asymbiotica. Our findings indicate that Pam plays an important role in enhancing surface attachment in insect blood. Its association with exopolysaccharide suggests it may exert its effect through mediation of

  19. Photorhabdus adhesion modification protein (Pam binds extracellular polysaccharide and alters bacterial attachment

    Directory of Open Access Journals (Sweden)

    Joyce Susan A

    2010-05-01

    Full Text Available Abstract Background Photorhabdus are Gram-negative nematode-symbiotic and insect-pathogenic bacteria. The species Photorhabdus asymbiotica is able to infect humans as well as insects. We investigated the secreted proteome of a clinical isolate of P. asymbiotica at different temperatures in order to identify proteins relevant to the infection of the two different hosts. Results A comparison of the proteins secreted by a clinical isolate of P. asymbiotica at simulated insect (28°C and human (37°C temperatures led to the identification of a small and highly abundant protein, designated Pam, that is only secreted at the lower temperature. The pam gene is present in all Photorhabdus strains tested and shows a high level of conservation across the whole genus, suggesting it is both ancestral to the genus and probably important to the biology of the bacterium. The Pam protein shows limited sequence similarity to the 13.6 kDa component of a binary toxin of Bacillus thuringiensis. Nevertheless, injection or feeding of heterologously produced Pam showed no insecticidal activity to either Galleria mellonella or Manduca sexta larvae. In bacterial colonies, Pam is associated with an extracellular polysaccharide (EPS-like matrix, and modifies the ability of wild-type cells to attach to an artificial surface. Interestingly, Surface Plasmon Resonance (SPR binding studies revealed that the Pam protein itself has adhesive properties. Although Pam is produced throughout insect infection, genetic knockout does not affect either insect virulence or the ability of P. luminescens to form a symbiotic association with its host nematode, Heterorhabditis bacteriophora. Conclusions We studied a highly abundant protein, Pam, which is secreted in a temperature-dependent manner in P. asymbiotica. Our findings indicate that Pam plays an important role in enhancing surface attachment in insect blood. Its association with exopolysaccharide suggests it may exert its effect

  20. N-acetyl-L-cysteine affects growth, extracellular polysaccharide production, and bacterial biofilm formation on solid surfaces.

    Science.gov (United States)

    Olofsson, Ann-Cathrin; Hermansson, Malte; Elwing, Hans

    2003-08-01

    N-Acetyl-L-cysteine (NAC) is used in medical treatment of patients with chronic bronchitis. The positive effects of NAC treatment have primarily been attributed to the mucus-dissolving properties of NAC, as well as its ability to decrease biofilm formation, which reduces bacterial infections. Our results suggest that NAC also may be an interesting candidate for use as an agent to reduce and prevent biofilm formation on stainless steel surfaces in environments typical of paper mill plants. Using 10 different bacterial strains isolated from a paper mill, we found that the mode of action of NAC is chemical, as well as biological, in the case of bacterial adhesion to stainless steel surfaces. The initial adhesion of bacteria is dependent on the wettability of the substratum. NAC was shown to bind to stainless steel, increasing the wettability of the surface. Moreover, NAC decreased bacterial adhesion and even detached bacteria that were adhering to stainless steel surfaces. Growth of various bacteria, as monocultures or in a multispecies community, was inhibited at different concentrations of NAC. We also found that there was no detectable degradation of extracellular polysaccharides (EPS) by NAC, indicating that NAC reduced the production of EPS, in most bacteria tested, even at concentrations at which growth was not affected. Altogether, the presence of NAC changes the texture of the biofilm formed and makes NAC an interesting candidate for use as a general inhibitor of formation of bacterial biofilms on stainless steel surfaces.

  1. N-acetyl-L-cysteine affects growth, extracellular polysaccharide production, and bacterial biofilm formation on solid surfaces.

    Science.gov (United States)

    Olofsson, Ann-Cathrin; Hermansson, Malte; Elwing, Hans

    2003-08-01

    N-Acetyl-L-cysteine (NAC) is used in medical treatment of patients with chronic bronchitis. The positive effects of NAC treatment have primarily been attributed to the mucus-dissolving properties of NAC, as well as its ability to decrease biofilm formation, which reduces bacterial infections. Our results suggest that NAC also may be an interesting candidate for use as an agent to reduce and prevent biofilm formation on stainless steel surfaces in environments typical of paper mill plants. Using 10 different bacterial strains isolated from a paper mill, we found that the mode of action of NAC is chemical, as well as biological, in the case of bacterial adhesion to stainless steel surfaces. The initial adhesion of bacteria is dependent on the wettability of the substratum. NAC was shown to bind to stainless steel, increasing the wettability of the surface. Moreover, NAC decreased bacterial adhesion and even detached bacteria that were adhering to stainless steel surfaces. Growth of various bacteria, as monocultures or in a multispecies community, was inhibited at different concentrations of NAC. We also found that there was no detectable degradation of extracellular polysaccharides (EPS) by NAC, indicating that NAC reduced the production of EPS, in most bacteria tested, even at concentrations at which growth was not affected. Altogether, the presence of NAC changes the texture of the biofilm formed and makes NAC an interesting candidate for use as a general inhibitor of formation of bacterial biofilms on stainless steel surfaces. PMID:12902275

  2. Bacterial glycobiology: rhamnose-containing cell wall polysaccharides in Gram-positive bacteria.

    OpenAIRE

    Mistou, Michel-Yves; Sutcliffe, Iain; van Sorge, Nina

    2016-01-01

    The composition of the Gram-positive cell wall is typically described as containing peptidoglycan, proteins and essential secondary cell wall structures called teichoic acids, which comprise approximately half of the cell wall mass. The cell walls of many species within the genera Streptococcus, Enterococcus and Lactococcus contain large amounts of the sugar rhamnose, which is incorporated in cell wall-anchored polysaccharides (CWP) that possibly function as homologues of well-studied wall te...

  3. Biosynthesis of Levan, a Bacterial Extracellular Polysaccharide, in the Yeast Saccharomyces cerevisiae

    OpenAIRE

    Franken, Jaco; Bianca A Brandt; Siew L Tai; Bauer, Florian F.

    2013-01-01

    Levans are fructose polymers synthesized by a broad range of micro-organisms and a limited number of plant species as non-structural storage carbohydrates. In microbes, these polymers contribute to the formation of the extracellular polysaccharide (EPS) matrix and play a role in microbial biofilm formation. Levans belong to a larger group of commercially important polymers, referred to as fructans, which are used as a source of prebiotic fibre. For levan, specifically, this market remains unt...

  4. Protecting the herd: the remarkable effectiveness of the bacterial meningitis polysaccharide-protein conjugate vaccines in altering transmission dynamics.

    Science.gov (United States)

    Stephens, David S

    2011-01-01

    Interrupting human-to-human transmission of the agents (Neisseria meningitidis, Haemophilus influenzae, and Streptococcus pneumoniae) of bacterial meningitis by new capsular polysaccharide-protein conjugate vaccines (PPCVs) has proven to be a remarkable (and unanticipated) contributor to vaccine effectiveness. Herd immunity accounts for ∼50% of the protection by meningococcal serogroup C PPCVs, pneumococcal PPCV7, and H. influenzae b PPCVs. Nasopharyngeal carriage can be reduced ≥75% for vaccine serotypes; the decrease in carriage is correlated with disease reduction in unvaccinated individuals, and the impact of herd immunity lasts for years. Based on these data, models for using herd immunity in vaccine-based prevention strategies are underway for control of meningitis in sub-Saharan Africa. Although the immunologic basis of herd immunity and impact on microbial biology need more study, protecting the unvaccinated by altering pathogen transmission dynamics is a powerful effect of PPCVs and increasingly important in vaccine introduction, implementation, and evaluation strategies.

  5. Nonstarch polysaccharides modulate bacterial microbiota, pathways for butyrate production, and abundance of pathogenic Escherichia coli in the pig gastrointestinal tract.

    Science.gov (United States)

    Metzler-Zebeli, Barbara U; Hooda, Seema; Pieper, Robert; Zijlstra, Ruurd T; van Kessel, Andrew G; Mosenthin, Rainer; Gänzle, Michael G

    2010-06-01

    The impact of nonstarch polysaccharides (NSP) differing in their functional properties on intestinal bacterial community composition, prevalence of butyrate production pathway genes, and occurrence of Escherichia coli virulence factors was studied for eight ileum-cannulated growing pigs by use of terminal restriction fragment length polymorphism (TRFLP) and quantitative PCR. A cornstarch- and casein-based diet was supplemented with low-viscosity, low-fermentability cellulose (CEL), with high-viscosity, low-fermentability carboxymethylcellulose (CMC), with low-viscosity, high-fermentability oat beta-glucan (LG), and with high-viscosity, high-fermentability oat beta-glucan (HG). Only minor effects of NSP fractions on the ileal bacterial community were observed, but NSP clearly changed the digestion in the small intestine. Compared to what was observed for CMC, more fermentable substrate was transferred into the large intestine with CEL, LG, and HG, resulting in higher levels of postileal dry-matter disappearance. Linear discriminant analysis of NSP and TRFLP profiles and 16S rRNA gene copy numbers for major bacterial groups revealed that CMC resulted in a distinctive bacterial community in comparison to the other NSP, which was characterized by higher gene copy numbers for total bacteria, Bacteroides-Prevotella-Porphyromonas, Clostridium cluster XIVa, and Enterobacteriaceae and increased prevalences of E. coli virulence factors in feces. The numbers of butyryl-coenzyme A (CoA) CoA transferase gene copies were higher than those of butyrate kinase gene copies in feces, and these quantities were affected by NSP. The present results suggest that the NSP fractions clearly and distinctly affected the taxonomic composition and metabolic features of the fecal microbiota. However, the effects were more linked to the individual NSP and to their effect on nutrient flow into the large intestine than to their shared functional properties.

  6. Biosynthesis of levan, a bacterial extracellular polysaccharide, in the yeast Saccharomyces cerevisiae.

    Science.gov (United States)

    Franken, Jaco; Brandt, Bianca A; Tai, Siew L; Bauer, Florian F

    2013-01-01

    Levans are fructose polymers synthesized by a broad range of micro-organisms and a limited number of plant species as non-structural storage carbohydrates. In microbes, these polymers contribute to the formation of the extracellular polysaccharide (EPS) matrix and play a role in microbial biofilm formation. Levans belong to a larger group of commercially important polymers, referred to as fructans, which are used as a source of prebiotic fibre. For levan, specifically, this market remains untapped, since no viable production strategy has been established. Synthesis of levan is catalysed by a group of enzymes, referred to as levansucrases, using sucrose as substrate. Heterologous expression of levansucrases has been notoriously difficult to achieve in Saccharomyces cerevisiae. As a strategy, this study used an invertase (Δsuc2) null mutant and two separate, engineered, sucrose accumulating yeast strains as hosts for the expression of the levansucrase M1FT, previously cloned from Leuconostoc mesenteroides. Intracellular sucrose accumulation was achieved either by expression of a sucrose synthase (Susy) from potato or the spinach sucrose transporter (SUT). The data indicate that in both Δsuc2 and the sucrose accumulating strains, the M1FT was able to catalyse fructose polymerisation. In the absence of the predicted M1FT secretion signal, intracellular levan accumulation was significantly enhanced for both sucrose accumulation strains, when grown on minimal media. Interestingly, co-expression of M1FT and SUT resulted in hyper-production and extracellular build-up of levan when grown in rich medium containing sucrose. This study presents the first report of levan production in S. cerevisiae and opens potential avenues for the production of levan using this well established industrial microbe. Furthermore, the work provides interesting perspectives when considering the heterologous expression of sugar polymerizing enzymes in yeast. PMID:24147008

  7. A Clostridium difficile Cell Wall Glycopolymer Locus Influences Bacterial Shape, Polysaccharide Production and Virulence

    Science.gov (United States)

    Bertolo, Lisa; Monteiro, Mario A.; Agellon, Al; Viswanathan, V. K.; Vedantam, Gayatri

    2016-01-01

    Clostridium difficile is a diarrheagenic pathogen associated with significant mortality and morbidity. While its glucosylating toxins are primary virulence determinants, there is increasing appreciation of important roles for non-toxin factors in C. difficile pathogenesis. Cell wall glycopolymers (CWGs) influence the virulence of various pathogens. Five C. difficile CWGs, including PSII, have been structurally characterized, but their biosynthesis and significance in C. difficile infection is unknown. We explored the contribution of a conserved CWG locus to C. difficile cell-surface integrity and virulence. Attempts at disrupting multiple genes in the locus, including one encoding a predicted CWG exporter mviN, were unsuccessful, suggesting essentiality of the respective gene products. However, antisense RNA-mediated mviN downregulation resulted in slight morphology defects, retarded growth, and decreased surface PSII deposition. Two other genes, lcpA and lcpB, with putative roles in CWG anchoring, could be disrupted by insertional inactivation. lcpA- and lcpB- mutants had distinct phenotypes, implying non-redundant roles for the respective proteins. The lcpB- mutant was defective in surface PSII deposition and shedding, and exhibited a remodeled cell surface characterized by elongated and helical morphology, aberrantly-localized cell septae, and an altered surface-anchored protein profile. Both lcpA- and lcpB- strains also displayed heightened virulence in a hamster model of C. difficile disease. We propose that gene products of the C. difficile CWG locus are essential, that they direct the production/assembly of key antigenic surface polysaccharides, and thereby have complex roles in virulence. PMID:27741317

  8. Biosynthesis of levan, a bacterial extracellular polysaccharide, in the yeast Saccharomyces cerevisiae.

    Directory of Open Access Journals (Sweden)

    Jaco Franken

    Full Text Available Levans are fructose polymers synthesized by a broad range of micro-organisms and a limited number of plant species as non-structural storage carbohydrates. In microbes, these polymers contribute to the formation of the extracellular polysaccharide (EPS matrix and play a role in microbial biofilm formation. Levans belong to a larger group of commercially important polymers, referred to as fructans, which are used as a source of prebiotic fibre. For levan, specifically, this market remains untapped, since no viable production strategy has been established. Synthesis of levan is catalysed by a group of enzymes, referred to as levansucrases, using sucrose as substrate. Heterologous expression of levansucrases has been notoriously difficult to achieve in Saccharomyces cerevisiae. As a strategy, this study used an invertase (Δsuc2 null mutant and two separate, engineered, sucrose accumulating yeast strains as hosts for the expression of the levansucrase M1FT, previously cloned from Leuconostoc mesenteroides. Intracellular sucrose accumulation was achieved either by expression of a sucrose synthase (Susy from potato or the spinach sucrose transporter (SUT. The data indicate that in both Δsuc2 and the sucrose accumulating strains, the M1FT was able to catalyse fructose polymerisation. In the absence of the predicted M1FT secretion signal, intracellular levan accumulation was significantly enhanced for both sucrose accumulation strains, when grown on minimal media. Interestingly, co-expression of M1FT and SUT resulted in hyper-production and extracellular build-up of levan when grown in rich medium containing sucrose. This study presents the first report of levan production in S. cerevisiae and opens potential avenues for the production of levan using this well established industrial microbe. Furthermore, the work provides interesting perspectives when considering the heterologous expression of sugar polymerizing enzymes in yeast.

  9. Bacterial polysaccharide levan as stabilizing, non-toxic and functional coating material for microelement-nanoparticles.

    Science.gov (United States)

    Bondarenko, Olesja M; Ivask, Angela; Kahru, Anne; Vija, Heiki; Titma, Tiina; Visnapuu, Meeri; Joost, Urmas; Pudova, Ksenia; Adamberg, Signe; Visnapuu, Triinu; Alamäe, Tiina

    2016-01-20

    Levan, fructose-composed biopolymer of bacterial origin, has potential in biotechnology due to its prebiotic and immunostimulatory properties. In this study levan synthesized by levansucrase from Pseudomonas syringae was thoroughly characterized and used as multifunctional biocompatible coating material for microelement-nanoparticles (NPs) of selenium, iron and cobalt. Transmission electron microscopy (TEM), hydrodynamic size measurements (DLS) and X-ray photoelectron spectroscopy (XPS) showed the interaction of levan with NPs. Levan stabilized the dispersions of NPs, decreased their toxicity and had protective effect on human intestinal cells Caco-2. In addition, levan attached to cobalt NPs remained accessible as a substrate for the colon bacteria Bacteroides thetaiotaomicron. We suggest that the combination of levan and nutritionally important microelements in the form of NPs serves as a first step towards a novel "2 in 1" approach for food supplements to provide safe and efficient delivery of microelements for humans and support beneficial gut microbiota with nutritional oligosaccharides. PMID:26572404

  10. Polysaccharide-capped silver Nanoparticles inhibit biofilm formation and eliminate multi-drug-resistant bacteria by disrupting bacterial cytoskeleton with reduced cytotoxicity towards mammalian cells

    Science.gov (United States)

    Sanyasi, Sridhar; Majhi, Rakesh Kumar; Kumar, Satish; Mishra, Mitali; Ghosh, Arnab; Suar, Mrutyunjay; Satyam, Parlapalli Venkata; Mohapatra, Harapriya; Goswami, Chandan; Goswami, Luna

    2016-04-01

    Development of effective anti-microbial therapeutics has been hindered by the emergence of bacterial strains with multi-drug resistance and biofilm formation capabilities. In this article, we report an efficient green synthesis of silver nanoparticle (AgNP) by in situ reduction and capping with a semi-synthetic polysaccharide-based biopolymer (carboxymethyl tamarind polysaccharide). The CMT-capped AgNPs were characterized by UV, DLS, FE-SEM, EDX and HR-TEM. These AgNPs have average particle size of ~20–40 nm, and show long time stability, indicated by their unchanged SPR and Zeta-potential values. These AgNPs inhibit growth and biofilm formation of both Gram positive (B. subtilis) and Gram negative (E. coli and Salmonella typhimurium) bacterial strains even at concentrations much lower than the minimum inhibitory concentration (MIC) breakpoints of antibiotics, but show reduced or no cytotoxicity against mammalian cells. These AgNPs alter expression and positioning of bacterial cytoskeletal proteins FtsZ and FtsA. CMT-capped AgNPs can effectively block growth of several clinical isolates and MDR strains representing different genera and resistant towards multiple antibiotics belonging to different classes. We propose that the CMT-capped AgNPs can have potential bio-medical application against multi-drug-resistant microbes with minimal cytotoxicity towards mammalian cells.

  11. Polysaccharide Degradation

    Science.gov (United States)

    Stone, Bruce A.; Svensson, Birte; Collins, Michelle E.; Rastall, Robert A.

    An overview of current and potential enzymes used to degrade polysaccharides is presented. Such depolymerases are comprised of glycoside hydrolases, glycosyl transferases, phosphorylases and lyases, and their classification, active sites and action patterns are discussed. Additionally, the mechanisms that these enzymes use to cleave glycosidic linkages is reviewed as are inhibitors of depolymerase activity; reagents which react with amino acid residues, glycoside derivatives, transition state inhibitors and proteinaceous inhibitors. The characterization of various enzymes of microbial, animal or plant origin has led to their widespread use in the production of important oligosaccharides which can be incorporated into food stuffs. Sources of polysaccharides of particular interest in this chapter are those from plants and include inulin, dextran, xylan and pectin, as their hydrolysis products are purported to be functional foods in the context of gastrointestinal health. An alternative use of degraded polysaccharides is in the treatment of disease. The possibility exists to treat bacterial exopolysaccharide with lyases from bacteriophage to produce oligosaccharides exhibiting bioactive sequences. Although this area is currently in its infancy the knowledge is available to investigate further.

  12. Competitive adsorption of Reactive Orange 16 and Reactive Brilliant Blue R on polyaniline/bacterial extracellular polysaccharides composite-A novel eco-friendly polymer

    Energy Technology Data Exchange (ETDEWEB)

    Janaki, V. [Department of Chemistry, Periyar University, Salem 636011, Tamil Nadu (India); Vijayaraghavan, K. [Singapore-Delft Water Alliance, National University of Singapore, 117577 (Singapore); Ramasamy, A.K. [Department of Chemistry, Periyar University, Salem 636011, Tamil Nadu (India); Lee, Kui-Jae [Division of Biotechnology, Advanced Institute of Environment and Bioscience, College of Environmental and Bioresource Sciences, Chonbuk National University, Iksan 570752 (Korea, Republic of); Oh, Byung-Taek, E-mail: btoh@jbnu.ac.kr [Division of Biotechnology, Advanced Institute of Environment and Bioscience, College of Environmental and Bioresource Sciences, Chonbuk National University, Iksan 570752 (Korea, Republic of); Kamala-Kannan, Seralathan, E-mail: kannan@jbnu.ac.kr [Division of Biotechnology, Advanced Institute of Environment and Bioscience, College of Environmental and Bioresource Sciences, Chonbuk National University, Iksan 570752 (Korea, Republic of)

    2012-11-30

    Highlights: Black-Right-Pointing-Pointer Competitive adsorption of reactive dyes onto polyaniline/bacterial extracellular polysaccharides composite. Black-Right-Pointing-Pointer The composite have functional groups of both polyaniline and bacterial extracellular polysaccharides. Black-Right-Pointing-Pointer The presence of Reactive Brilliant Blue R diminished the uptake of Reactive Orange 16. Black-Right-Pointing-Pointer Electrostatic interaction was identified as a major mechanism in adsorption process. Black-Right-Pointing-Pointer Reactive Brilliant Blue R and Reactive Orange 16 adsorption was endothermic process. - Abstract: The performance of polyaniline/extracellular polymeric substances (Pn/EPS) composite as an adsorbent to remove the anionic reactive dyes, Reactive Brilliant Blue R (RBBR) and Reactive Orange 16 (RO), was investigated in single and binary systems. The pH{sub pzc} of Pn/EPS composite was calculated as 3.7 through potentiometric mass titration method. Electrostatic interaction between the dye anion and the nitrogen present in the polymer was identified as a major mechanism in adsorption process. Single component isotherms followed the Langmuir model with the maximum adsorption capacity of 0.5775 mmol g{sup -1} for RBBR and 0.4748 mmol g{sup -1} for RO. In binary system, both the reactive dye anions compete with each other and resulted in lower uptake. Binary adsorption data were interpreted well by the Sheindorf-Rehbun-Sheintuch equation as compared to extended Langmuir model with constant interaction factor. Kinetic analysis of single solute followed pseudo-first order model. Thermodynamic studies computed that RBBR and RO adsorption was endothermic, spontaneous, and feasible process.

  13. Molecular insight into the role of the N-terminal extension in the maturation, substrate recognition, and catalysis of a bacterial alginate lyase from polysaccharide lyase family 18.

    Science.gov (United States)

    Dong, Sheng; Wei, Tian-Di; Chen, Xiu-Lan; Li, Chun-Yang; Wang, Peng; Xie, Bin-Bin; Qin, Qi-Long; Zhang, Xi-Ying; Pang, Xiu-Hua; Zhou, Bai-Cheng; Zhang, Yu-Zhong

    2014-10-24

    Bacterial alginate lyases, which are members of several polysaccharide lyase (PL) families, have important biological roles and biotechnological applications. The mechanisms for maturation, substrate recognition, and catalysis of PL18 alginate lyases are still largely unknown. A PL18 alginate lyase, aly-SJ02, from Pseudoalteromonas sp. 0524 displays a β-jelly roll scaffold. Structural and biochemical analyses indicated that the N-terminal extension in the aly-SJ02 precursor may act as an intramolecular chaperone to mediate the correct folding of the catalytic domain. Molecular dynamics simulations and mutational assays suggested that the lid loops over the aly-SJ02 active center serve as a gate for substrate entry. Molecular docking and site-directed mutations revealed that certain conserved residues at the active center, especially those at subsites +1 and +2, are crucial for substrate recognition. Tyr(353) may function as both a catalytic base and acid. Based on our results, a model for the catalysis of aly-SJ02 in alginate depolymerization is proposed. Moreover, although bacterial alginate lyases from families PL5, 7, 15, and 18 adopt distinct scaffolds, they share the same conformation of catalytic residues, reflecting their convergent evolution. Our results provide the foremost insight into the mechanisms of maturation, substrate recognition, and catalysis of a PL18 alginate lyase.

  14. Bacterial fucose-rich polysaccharide stabilizes MAPK-mediated Nrf2/Keap1 signaling by directly scavenging reactive oxygen species during hydrogen peroxide-induced apoptosis of human lung fibroblast cells.

    Directory of Open Access Journals (Sweden)

    Sougata Roy Chowdhury

    Full Text Available Continuous free radical assault upsets cellular homeostasis and dysregulates associated signaling pathways to promote stress-induced cell death. In spite of the continuous development and implementation of effective therapeutic strategies, limitations in treatments for stress-induced toxicities remain. The purpose of the present study was to determine the potential therapeutic efficacy of bacterial fucose polysaccharides against hydrogen peroxide (H2O2-induced stress in human lung fibroblast (WI38 cells and to understand the associated molecular mechanisms. In two different fermentation processes, Bacillus megaterium RB-05 biosynthesized two non-identical fucose polysaccharides; of these, the polysaccharide having a high-fucose content (∼ 42% conferred the maximum free radical scavenging efficiency in vitro. Structural characterizations of the purified polysaccharides were performed using HPLC, GC-MS, and (1H/(13C/2D-COSY NMR. H2O2 (300 µM insult to WI38 cells showed anti-proliferative effects by inducing intracellular reactive oxygen species (ROS and by disrupting mitochondrial membrane permeability, followed by apoptosis. The polysaccharide (250 µg/mL attenuated the cell death process by directly scavenging intracellular ROS rather than activating endogenous antioxidant enzymes. This process encompasses inhibition of caspase-9/3/7, a decrease in the ratio of Bax/Bcl2, relocalization of translocated Bax and cytochrome c, upregulation of anti-apoptotic members of the Bcl2 family and a decrease in the phosphorylation of MAPKs (mitogen activated protein kinases. Furthermore, cellular homeostasis was re-established via stabilization of MAPK-mediated Nrf2/Keap1 signaling and transcription of downstream cytoprotective genes. This molecular study uniquely introduces a fucose-rich bacterial polysaccharide as a potential inhibitor of H2O2-induced stress and toxicities.

  15. Bacterial fucose-rich polysaccharide stabilizes MAPK-mediated Nrf2/Keap1 signaling by directly scavenging reactive oxygen species during hydrogen peroxide-induced apoptosis of human lung fibroblast cells.

    Science.gov (United States)

    Roy Chowdhury, Sougata; Sengupta, Suman; Biswas, Subir; Sinha, Tridib Kumar; Sen, Ramkrishna; Basak, Ratan Kumar; Adhikari, Basudam; Bhattacharyya, Arindam

    2014-01-01

    Continuous free radical assault upsets cellular homeostasis and dysregulates associated signaling pathways to promote stress-induced cell death. In spite of the continuous development and implementation of effective therapeutic strategies, limitations in treatments for stress-induced toxicities remain. The purpose of the present study was to determine the potential therapeutic efficacy of bacterial fucose polysaccharides against hydrogen peroxide (H2O2)-induced stress in human lung fibroblast (WI38) cells and to understand the associated molecular mechanisms. In two different fermentation processes, Bacillus megaterium RB-05 biosynthesized two non-identical fucose polysaccharides; of these, the polysaccharide having a high-fucose content (∼ 42%) conferred the maximum free radical scavenging efficiency in vitro. Structural characterizations of the purified polysaccharides were performed using HPLC, GC-MS, and (1)H/(13)C/2D-COSY NMR. H2O2 (300 µM) insult to WI38 cells showed anti-proliferative effects by inducing intracellular reactive oxygen species (ROS) and by disrupting mitochondrial membrane permeability, followed by apoptosis. The polysaccharide (250 µg/mL) attenuated the cell death process by directly scavenging intracellular ROS rather than activating endogenous antioxidant enzymes. This process encompasses inhibition of caspase-9/3/7, a decrease in the ratio of Bax/Bcl2, relocalization of translocated Bax and cytochrome c, upregulation of anti-apoptotic members of the Bcl2 family and a decrease in the phosphorylation of MAPKs (mitogen activated protein kinases). Furthermore, cellular homeostasis was re-established via stabilization of MAPK-mediated Nrf2/Keap1 signaling and transcription of downstream cytoprotective genes. This molecular study uniquely introduces a fucose-rich bacterial polysaccharide as a potential inhibitor of H2O2-induced stress and toxicities.

  16. Towards an understanding of a0-f0 mixing

    CERN Document Server

    Hanhart, Christoph; Pelaez, Jose R

    2007-01-01

    We investigate the isospin-violating mixing of the light scalar mesons a0(980) and f0(980) within the unitarized chiral approach. Isospin-violating effects are considered to leading order in the quark mass differences and electromagnetism. In this approach both mesons are generated through meson-meson dynamics. Thus our results might be considered as benchmark results for the mixing phenomenon within a framework consistent with chiral symmetry and unitarity, where these resonances are not predominantly q q-bar states. Amongst the possible experimental signals, we discuss observable consequences for the reaction J/Psi -> phi pi0 eta in detail. In particular we demonstrate that the effect of a0-f0 mixing is by far the most important isospin-breaking effect in the resonance region and can indeed be extracted from experiment.

  17. Polysaccharide Nanostructures

    OpenAIRE

    Kontogiorgos, Vassilis

    2014-01-01

    Polysaccharides are carbohydrate polymers where sugar units are linked together through glycosidic linkages. In living organisms polysaccharides are the structural polymers that provide support (e.g., cellulose in plants or chitin in arthropods) or the sources of energy for plant development (e.g., starch). Polysaccharides are routinely used in the food industry, most frequently as thickeners, stabilizers of dispersions (emulsions, foams) or structuring agents of water and air.

  18. Low fucose containing bacterial polysaccharide facilitate mitochondria-dependent ROS-induced apoptosis of human lung epithelial carcinoma via controlled regulation of MAPKs-mediated Nrf2/Keap1 homeostasis signaling.

    Science.gov (United States)

    Chowdhury, Sougata Roy; Sengupta, Suman; Biswas, Subir; Sen, Ramkrishna; Sinha, Tridib Kumar; Basak, Ratan Kumar; Adhikari, Basudam; Bhattacharyya, Arindam

    2015-12-01

    Reactive oxygen species (ROS), the key mediators of cellular oxidative stress and redox dysregulation involved in cancer initiation and progression, have recently emerged as promising targets for anticancer drug discovery. Continuous free radical assault upsets homeostasis in cellular redox system and regulates the associated signaling pathways to mediate stress-induced cell death. This study investigates the dose-specific pro-oxidative behavior of a bacterial fucose polysaccharide, which attenuated proliferation of different cancer cells. In the fermentation process, Bacillus megaterium RB-05 [GenBank Accession Number HM371417] was found to biosynthesize a polysaccharide with low-fucose content (4.9%), which conferred the maximum anti-proliferative activity (750 µg/mL) against human lung cancer epithelial cells (A549) during preliminary screening. Structural elucidation and morphological characterization of the duly purified polysaccharide was done using HPLC, GC-MS, (1)H/(13)C NMR, and microscopy. The polysaccharide exhibited concentration- and time-dependent anti-proliferative effects against A549 cells by inducing intracellular ROS level and regulating the mitochondrial membrane-permeability following the apoptotic pathway. This process encompasses activation of caspase-8/9/3/7, increase in the ratio of Bax/Bcl2 ratio, translocation of Bcl2-associated X protein (Bax) and cytochrome c, decrease in expression of anti-apoptotic members of Bcl2 family, and phosphorylation of mitogen activated protein kinases (MAPKs). Apoptosis was attenuated upon pretreatment with specific caspase-inhibitors. Simultaneously, during apoptosis, the ROS-mediated stress as well as activated MAPKs triggered nuclear translocation of transcription factors like nuclear factor (erythroid-derived)-like 2 (Nrf2) and promoted further transcription of downstream cytoprotective genes, which somehow perturbed the chemotherapeutic efficacy of the polysaccharide, although using CuPP, a chemical

  19. Effects of Plant Cell Wall Matrix Polysaccharides on Bacterial Cellulose Structure Studied with Vibrational Sum Frequency Generation Spectroscopy and X-ray Diffraction

    Energy Technology Data Exchange (ETDEWEB)

    Park, Yong Bum; Lee, Christopher M; Kafle, Kabindra; Park, Sunkyu; Cosgrove, Daniel; Kim, Seong H

    2014-07-14

    The crystallinity, allomorph content, and mesoscale ordering of cellulose produced by Gluconacetobacter xylinus cultured with different plant cell wall matrix polysaccharides were studied with vibrational sum frequency generation (SFG) spectroscopy and X-ray diffraction (XRD).

  20. In vitro study on polysaccharides from Paeonia sinjiangensis K.Y. Pan on the effect of caries factors of oral cariogenic bacterial%芍药总多糖抑龋作用的体外研究

    Institute of Scientific and Technical Information of China (English)

    李贺; 李艳; 赵今

    2016-01-01

    Objective To investigate the effect of polysaccharides from Paeonia sinjiangensis K.Y. Pan on the growth, acid production, glucan generation of Streptococcus mutans,Streptococcus sanguis and Actinomyces viscosus. Methods By the method of solvent extraction process, the polysaccharides was extracted from Paeonia sinjiangensis K.Y. Pan.Two-fold dilution was used to measure Minimal inhibitory concentration (MIC) and minimal bactericidal concentration (MBC) of polysaccharide from Paeonia sinjiangensis K.Y. Pan effecting on the growth of Streptococcus mutans,Streptococcus sanguis and Actinomyces viscosus.The polysaccharides from Paeonia sinjiangensis K.Y. Pan was used as the experimental group with concentrations ranging from 1/2MIC to 1/16MIC prepared with brain heart infusion broth(BHI) liquid medium, and BHI liquid medium was used as the control group. Using pH meter measure ΔpH and Anthrone measured the effect of polysaccharide on acid ogenicity of oral cariogenic bacterial and on intracellular polysaccharide. Results ①Total polysaccharides from Paeonia sinjiangensis K.Y. Pan significantly inhibited the growth of Streptococcus mutans,Streptococcus sanguis and Actinomyces viscosus, of which MIC measured by dilution experiments were, respectively,110.4mg/ml,13.8mg/ml and 27.6 mg/ml.②Total polysaccharides from Paeonia sinjiangensis K.Y. Pan inhibited acid production of Streptococcus mutans,Streptococcus sanguis, while its effect of Actinomyces viscosus, compared with the control group, had no significant difference. ③Total polysaccharides from Paeonia sinjiangensis K.Y. Pan had obvious inhibitory effect on the synthesis of intracellular polysaccharide(WIG) of Streptococcus mutans,Streptococcus sanguis, while in the experimental concentration, it had little effect on the synthesis of intracellular polysaccharide of Actinomyces viscosus. Conclusion Total polysaccharides from Paeonia sinjiangensis K.Y. Pan inhibits in vitro on growth of cariogenic bacterial

  1. Liposomal co-entrapment of CD40mAb induces enhanced IgG responses against bacterial polysaccharide and protein.

    Directory of Open Access Journals (Sweden)

    Caterina Hatzifoti

    Full Text Available BACKGROUND: Antibody against CD40 is effective in enhancing immune responses to vaccines when chemically conjugated to the vaccine antigen. Unfortunately the requirement for chemical conjugation presents some difficulties in vaccine production and quality control which are compounded when multivalent vaccines are required. We explore here an alternative to chemical conjugation, involving the co-encapsulation of CD40 antibody and antigens in liposomal vehicles. METHODOLOGY/PRINCIPAL FINDINGS: Anti-mouse CD40 mAb or isotype control mAb were co-entrapped individually in cationic liposomal vehicles with pneumococcal polysaccharides or diphtheria and tetanus toxoids. Retention of CD40 binding activity upon liposomal entrapment was assessed by ELISA and flow cytometry. After subcutaneous immunization of BALB/c female mice, anti-polysaccharide and DT/TT responses were measured by ELISA. Simple co-encapsulation of CD40 antibody allowed for the retention of CD40 binding on the liposome surface, and also produced vaccines with enhanced imunogenicity. Antibody responses against both co-entrapped protein in the form of tetanus toxoid, and Streptococcus pneumoniae capsular polysaccharide, were enhanced by co-encapsulation with CD40 antibody. Surprisingly, liposomal encapsulation also appeared to decrease the toxicity of high doses of CD40 antibody as assessed by the degree of splenomegaly induced. CONCLUSIONS/SIGNIFICANCE: Liposomal co-encapsulation with CD40 antibody may represent a practical means of producing more immunogenic multivalent vaccines and inducing IgG responses against polysaccharides without the need for conjugation.

  2. A buffer-regulated HF acid for sandstone acidizing to 550/sup 0/F

    Energy Technology Data Exchange (ETDEWEB)

    Scheuerman, R.F.

    1988-02-01

    Two earlier papers discussed the suitability of bugger-regulated HF acid (BRHFA) for high-temperature sandstone matrix stimulation treatments. Acetic-acid/acetate buffering (pH = 4.5 to 5.0) limited corrosion to acceptable levels at temperatures up to about 350/sup 0/F (177/sup 0/C). Subsequent development of reservoirs with temperatures approaching 450/sup 0/F (232/sup 0/C) demonstrated a need for even higher-temperature acidizing systems. This paper discusses a new, less corrosive BRHFA formulation that has clay-dissolving capacity comparable to 7 1/2% HCl/1 1/2% HF acid. The corrosion rate of carbon steel at 550/sup 0/F (288/sup 0/C) is only 330 mils/yr (8.4 mm/a). The BRHFA systems are also compatible with a variety of corrosion-resistant alloys. This paper presents clay slurry, core flow, and corrosion data and discusses use guidelines.

  3. Search for the decay $B^0_s\\to\\overline{D}^0f_0(980)$

    CERN Document Server

    Aaij, Roel; Adinolfi, Marco; Affolder, Anthony; Ajaltouni, Ziad; Akar, Simon; Albrecht, Johannes; Alessio, Federico; Alexander, Michael; Ali, Suvayu; Alkhazov, Georgy; Alvarez Cartelle, Paula; Alves Jr, Antonio Augusto; Amato, Sandra; Amerio, Silvia; Amhis, Yasmine; An, Liupan; Anderlini, Lucio; Anderson, Jonathan; Andreotti, Mirco; Andrews, Jason; Appleby, Robert; Aquines Gutierrez, Osvaldo; Archilli, Flavio; d'Argent, Philippe; Artamonov, Alexander; Artuso, Marina; Aslanides, Elie; Auriemma, Giulio; Baalouch, Marouen; Bachmann, Sebastian; Back, John; Badalov, Alexey; Baesso, Clarissa; Baldini, Wander; Barlow, Roger; Barschel, Colin; Barsuk, Sergey; Barter, William; Batozskaya, Varvara; Battista, Vincenzo; Bay, Aurelio; Beaucourt, Leo; Beddow, John; Bedeschi, Franco; Bediaga, Ignacio; Bel, Lennaert; Belyaev, Ivan; Ben-Haim, Eli; Bencivenni, Giovanni; Benson, Sean; Benton, Jack; Berezhnoy, Alexander; Bernet, Roland; Bertolin, Alessandro; Bettler, Marc-Olivier; van Beuzekom, Martinus; Bien, Alexander; Bifani, Simone; Bird, Thomas; Birnkraut, Alex; Bizzeti, Andrea; Blake, Thomas; Blanc, Frédéric; Blouw, Johan; Blusk, Steven; Bocci, Valerio; Bondar, Alexander; Bondar, Nikolay; Bonivento, Walter; Borghi, Silvia; Borsato, Martino; Bowcock, Themistocles; Bowen, Espen Eie; Bozzi, Concezio; Braun, Svende; Brett, David; Britsch, Markward; Britton, Thomas; Brodzicka, Jolanta; Brook, Nicholas; Bursche, Albert; Buytaert, Jan; Cadeddu, Sandro; Calabrese, Roberto; Calvi, Marta; Calvo Gomez, Miriam; Campana, Pierluigi; Campora Perez, Daniel; Capriotti, Lorenzo; Carbone, Angelo; Carboni, Giovanni; Cardinale, Roberta; Cardini, Alessandro; Carniti, Paolo; Carson, Laurence; Carvalho Akiba, Kazuyoshi; Casanova Mohr, Raimon; Casse, Gianluigi; Cassina, Lorenzo; Castillo Garcia, Lucia; Cattaneo, Marco; Cauet, Christophe; Cavallero, Giovanni; Cenci, Riccardo; Charles, Matthew; Charpentier, Philippe; Chefdeville, Maximilien; Chen, Shanzhen; Cheung, Shu-Faye; Chiapolini, Nicola; Chrzaszcz, Marcin; Cid Vidal, Xabier; Ciezarek, Gregory; Clarke, Peter; Clemencic, Marco; Cliff, Harry; Closier, Joel; Coco, Victor; Cogan, Julien; Cogneras, Eric; Cogoni, Violetta; Cojocariu, Lucian; Collazuol, Gianmaria; Collins, Paula; Comerma-Montells, Albert; Contu, Andrea; Cook, Andrew; Coombes, Matthew; Coquereau, Samuel; Corti, Gloria; Corvo, Marco; Couturier, Benjamin; Cowan, Greig; Craik, Daniel Charles; Crocombe, Andrew; Cruz Torres, Melissa Maria; Cunliffe, Samuel; Currie, Robert; D'Ambrosio, Carmelo; Dalseno, Jeremy; David, Pieter; Davis, Adam; De Bruyn, Kristof; De Capua, Stefano; De Cian, Michel; De Miranda, Jussara; De Paula, Leandro; De Silva, Weeraddana; De Simone, Patrizia; Dean, Cameron Thomas; Decamp, Daniel; Deckenhoff, Mirko; Del Buono, Luigi; Déléage, Nicolas; Derkach, Denis; Deschamps, Olivier; Dettori, Francesco; Dey, Biplab; Di Canto, Angelo; Di Ruscio, Francesco; Dijkstra, Hans; Donleavy, Stephanie; Dordei, Francesca; Dorigo, Mirco; Dosil Suárez, Alvaro; Dossett, David; Dovbnya, Anatoliy; Dreimanis, Karlis; Dujany, Giulio; Dupertuis, Frederic; Durante, Paolo; Dzhelyadin, Rustem; Dziurda, Agnieszka; Dzyuba, Alexey; Easo, Sajan; Egede, Ulrik; Egorychev, Victor; Eidelman, Semen; Eisenhardt, Stephan; Eitschberger, Ulrich; Ekelhof, Robert; Eklund, Lars; El Rifai, Ibrahim; Elsasser, Christian; Ely, Scott; Esen, Sevda; Evans, Hannah Mary; Evans, Timothy; Falabella, Antonio; Färber, Christian; Farinelli, Chiara; Farley, Nathanael; Farry, Stephen; Fay, Robert; Ferguson, Dianne; Fernandez Albor, Victor; Ferrari, Fabio; Ferreira Rodrigues, Fernando; Ferro-Luzzi, Massimiliano; Filippov, Sergey; Fiore, Marco; Fiorini, Massimiliano; Firlej, Miroslaw; Fitzpatrick, Conor; Fiutowski, Tomasz; Fol, Philip; Fontana, Marianna; Fontanelli, Flavio; Forty, Roger; Francisco, Oscar; Frank, Markus; Frei, Christoph; Frosini, Maddalena; Fu, Jinlin; Furfaro, Emiliano; Gallas Torreira, Abraham; Galli, Domenico; Gallorini, Stefano; Gambetta, Silvia; Gandelman, Miriam; Gandini, Paolo; Gao, Yuanning; García Pardiñas, Julián; Garofoli, Justin; Garra Tico, Jordi; Garrido, Lluis; Gascon, David; Gaspar, Clara; Gastaldi, Ugo; Gauld, Rhorry; Gavardi, Laura; Gazzoni, Giulio; Geraci, Angelo; Gerick, David; Gersabeck, Evelina; Gersabeck, Marco; Gershon, Timothy; Ghez, Philippe; Gianelle, Alessio; Gianì, Sebastiana; Gibson, Valerie; Giubega, Lavinia-Helena; Gligorov, Vladimir; Göbel, Carla; Golubkov, Dmitry; Golutvin, Andrey; Gomes, Alvaro; Gotti, Claudio; Grabalosa Gándara, Marc; Graciani Diaz, Ricardo; Granado Cardoso, Luis Alberto; Graugés, Eugeni; Graverini, Elena; Graziani, Giacomo; Grecu, Alexandru; Greening, Edward; Gregson, Sam; Griffith, Peter; Grillo, Lucia; Grünberg, Oliver; Gui, Bin; Gushchin, Evgeny; Guz, Yury; Gys, Thierry; Hadjivasiliou, Christos; Haefeli, Guido; Haen, Christophe; Haines, Susan; Hall, Samuel; Hamilton, Brian; Hampson, Thomas; Han, Xiaoxue; Hansmann-Menzemer, Stephanie; Harnew, Neville; Harnew, Samuel; Harrison, Jonathan; He, Jibo; Head, Timothy; Heijne, Veerle; Hennessy, Karol; Henrard, Pierre; Henry, Louis; Hernando Morata, Jose Angel; van Herwijnen, Eric; Heß, Miriam; Hicheur, Adlène; Hill, Donal; Hoballah, Mostafa; Hombach, Christoph; Hulsbergen, Wouter; Humair, Thibaud; Hussain, Nazim; Hutchcroft, David; Hynds, Daniel; Idzik, Marek; Ilten, Philip; Jacobsson, Richard; Jaeger, Andreas; Jalocha, Pawel; Jans, Eddy; Jawahery, Abolhassan; Jing, Fanfan; John, Malcolm; Johnson, Daniel; Jones, Christopher; Joram, Christian; Jost, Beat; Jurik, Nathan; Kandybei, Sergii; Kanso, Walaa; Karacson, Matthias; Karbach, Moritz; Karodia, Sarah; Kelsey, Matthew; Kenyon, Ian; Kenzie, Matthew; Ketel, Tjeerd; Khanji, Basem; Khurewathanakul, Chitsanu; Klaver, Suzanne; Klimaszewski, Konrad; Kochebina, Olga; Kolpin, Michael; Komarov, Ilya; Koopman, Rose; Koppenburg, Patrick; Korolev, Mikhail; Kravchuk, Leonid; Kreplin, Katharina; Kreps, Michal; Krocker, Georg; Krokovny, Pavel; Kruse, Florian; Kucewicz, Wojciech; Kucharczyk, Marcin; Kudryavtsev, Vasily; Kurek, Krzysztof; Kvaratskheliya, Tengiz; La Thi, Viet Nga; Lacarrere, Daniel; Lafferty, George; Lai, Adriano; Lambert, Dean; Lambert, Robert W; Lanfranchi, Gaia; Langenbruch, Christoph; Langhans, Benedikt; Latham, Thomas; Lazzeroni, Cristina; Le Gac, Renaud; van Leerdam, Jeroen; Lees, Jean-Pierre; Lefèvre, Regis; Leflat, Alexander; Lefrançois, Jacques; Leroy, Olivier; Lesiak, Tadeusz; Leverington, Blake; Li, Yiming; Likhomanenko, Tatiana; Liles, Myfanwy; Lindner, Rolf; Linn, Christian; Lionetto, Federica; Liu, Bo; Lohn, Stefan; Longstaff, Iain; Lopes, Jose; Lucchesi, Donatella; Lucio Martinez, Miriam; Luo, Haofei; Lupato, Anna; Luppi, Eleonora; Lupton, Oliver; Machefert, Frederic; Maciuc, Florin; Maev, Oleg; Malde, Sneha; Malinin, Alexander; Manca, Giulia; Mancinelli, Giampiero; Manning, Peter Michael; Mapelli, Alessandro; Maratas, Jan; Marchand, Jean François; Marconi, Umberto; Marin Benito, Carla; Marino, Pietro; Märki, Raphael; Marks, Jörg; Martellotti, Giuseppe; Martinelli, Maurizio; Martinez Santos, Diego; Martinez Vidal, Fernando; Martins Tostes, Danielle; Massafferri, André; Matev, Rosen; Mathad, Abhijit; Mathe, Zoltan; Matteuzzi, Clara; Matthieu, Kecke; Mauri, Andrea; Maurin, Brice; Mazurov, Alexander; McCann, Michael; McCarthy, James; McNab, Andrew; McNulty, Ronan; Meadows, Brian; Meier, Frank; Meissner, Marco; Merk, Marcel; Milanes, Diego Alejandro; Minard, Marie-Noelle; Mitzel, Dominik Stefan; Molina Rodriguez, Josue; Monteil, Stephane; Morandin, Mauro; Morawski, Piotr; Mordà, Alessandro; Morello, Michael Joseph; Moron, Jakub; Morris, Adam Benjamin; Mountain, Raymond; Muheim, Franz; Müller, Janine; Müller, Katharina; Müller, Vanessa; Mussini, Manuel; Muster, Bastien; Naik, Paras; Nakada, Tatsuya; Nandakumar, Raja; Nasteva, Irina; Needham, Matthew; Neri, Nicola; Neubert, Sebastian; Neufeld, Niko; Neuner, Max; Nguyen, Anh Duc; Nguyen, Thi-Dung; Nguyen-Mau, Chung; Niess, Valentin; Niet, Ramon; Nikitin, Nikolay; Nikodem, Thomas; Ninci, Daniele; Novoselov, Alexey; O'Hanlon, Daniel Patrick; Oblakowska-Mucha, Agnieszka; Obraztsov, Vladimir; Ogilvy, Stephen; Okhrimenko, Oleksandr; Oldeman, Rudolf; Onderwater, Gerco; Osorio Rodrigues, Bruno; Otalora Goicochea, Juan Martin; Otto, Adam; Owen, Patrick; Oyanguren, Maria Aranzazu; Palano, Antimo; Palombo, Fernando; Palutan, Matteo; Panman, Jacob; Papanestis, Antonios; Pappagallo, Marco; Pappalardo, Luciano; Parkes, Christopher; Passaleva, Giovanni; Patel, Girish; Patel, Mitesh; Patrignani, Claudia; Pearce, Alex; Pellegrino, Antonio; Penso, Gianni; Pepe Altarelli, Monica; Perazzini, Stefano; Perret, Pascal; Pescatore, Luca; Petridis, Konstantinos; Petrolini, Alessandro; Petruzzo, Marco; Picatoste Olloqui, Eduardo; Pietrzyk, Boleslaw; Pilař, Tomas; Pinci, Davide; Pistone, Alessandro; Playfer, Stephen; Plo Casasus, Maximo; Poikela, Tuomas; Polci, Francesco; Poluektov, Anton; Polyakov, Ivan; Polycarpo, Erica; Popov, Alexander; Popov, Dmitry; Popovici, Bogdan; Potterat, Cédric; Price, Eugenia; Price, Joseph David; Prisciandaro, Jessica; Pritchard, Adrian; Prouve, Claire; Pugatch, Valery; Puig Navarro, Albert; Punzi, Giovanni; Qian, Wenbin; Quagliani, Renato; Rachwal, Bartolomiej; Rademacker, Jonas; Rakotomiaramanana, Barinjaka; Rama, Matteo; Rangel, Murilo; Raniuk, Iurii; Rauschmayr, Nathalie; Raven, Gerhard; Redi, Federico; Reichert, Stefanie; Reid, Matthew; dos Reis, Alberto; Ricciardi, Stefania; Richards, Sophie; Rihl, Mariana; Rinnert, Kurt; Rives Molina, Vincente; Robbe, Patrick; Rodrigues, Ana Barbara; Rodrigues, Eduardo; Rodriguez Lopez, Jairo Alexis; Rodriguez Perez, Pablo; Roiser, Stefan; Romanovsky, Vladimir; Romero Vidal, Antonio; Rotondo, Marcello; Rouvinet, Julien; Ruf, Thomas; Ruiz, Hugo; Ruiz Valls, Pablo; Saborido Silva, Juan Jose; Sagidova, Naylya; Sail, Paul; Saitta, Biagio; Salustino Guimaraes, Valdir; Sanchez Mayordomo, Carlos; Sanmartin Sedes, Brais; Santacesaria, Roberta; Santamarina Rios, Cibran; Santovetti, Emanuele; Sarti, Alessio; Satriano, Celestina; Satta, Alessia; Saunders, Daniel Martin; Savrina, Darya; Schiller, Manuel; Schindler, Heinrich; Schlupp, Maximilian; Schmelling, Michael; Schmelzer, Timon; Schmidt, Burkhard; Schneider, Olivier; Schopper, Andreas; Schune, Marie Helene; Schwemmer, Rainer; Sciascia, Barbara; Sciubba, Adalberto; Semennikov, Alexander; Sepp, Indrek; Serra, Nicola; Serrano, Justine; Sestini, Lorenzo; Seyfert, Paul; Shapkin, Mikhail; Shapoval, Illya; Shcheglov, Yury; Shears, Tara; Shekhtman, Lev; Shevchenko, Vladimir; Shires, Alexander; Silva Coutinho, Rafael; Simi, Gabriele; Sirendi, Marek; Skidmore, Nicola; Skillicorn, Ian; Skwarnicki, Tomasz; Smith, Edmund; Smith, Eluned; Smith, Jackson; Smith, Mark; Snoek, Hella; Sokoloff, Michael; Soler, Paul; Soomro, Fatima; Souza, Daniel; Souza De Paula, Bruno; Spaan, Bernhard; Spradlin, Patrick; Sridharan, Srikanth; Stagni, Federico; Stahl, Marian; Stahl, Sascha; Steinkamp, Olaf; Stenyakin, Oleg; Sterpka, Christopher Francis; Stevenson, Scott; Stoica, Sabin; Stone, Sheldon; Storaci, Barbara; Stracka, Simone; Straticiuc, Mihai; Straumann, Ulrich; Stroili, Roberto; Sun, Liang; Sutcliffe, William; Swientek, Krzysztof; Swientek, Stefan; Syropoulos, Vasileios; Szczekowski, Marek; Szczypka, Paul; Szumlak, Tomasz; T'Jampens, Stephane; Tekampe, Tobias; Teklishyn, Maksym; Tellarini, Giulia; Teubert, Frederic; Thomas, Christopher; Thomas, Eric; van Tilburg, Jeroen; Tisserand, Vincent; Tobin, Mark; Todd, Jacob; Tolk, Siim; Tomassetti, Luca; Tonelli, Diego; Topp-Joergensen, Stig; Torr, Nicholas; Tournefier, Edwige; Tourneur, Stephane; Trabelsi, Karim; Tran, Minh Tâm; Tresch, Marco; Trisovic, Ana; Tsaregorodtsev, Andrei; Tsopelas, Panagiotis; Tuning, Niels; Ukleja, Artur; Ustyuzhanin, Andrey; Uwer, Ulrich; Vacca, Claudia; Vagnoni, Vincenzo; Valenti, Giovanni; Vallier, Alexis; Vazquez Gomez, Ricardo; Vazquez Regueiro, Pablo; Vázquez Sierra, Carlos; Vecchi, Stefania; Velthuis, Jaap; Veltri, Michele; Veneziano, Giovanni; Vesterinen, Mika; Viaud, Benoit; Vieira, Daniel; Vieites Diaz, Maria; Vilasis-Cardona, Xavier; Vollhardt, Achim; Volyanskyy, Dmytro; Voong, David; Vorobyev, Alexey; Vorobyev, Vitaly; Voß, Christian; de Vries, Jacco; Waldi, Roland; Wallace, Charlotte; Wallace, Ronan; Walsh, John; Wandernoth, Sebastian; Wang, Jianchun; Ward, David; Watson, Nigel; Websdale, David; Weiden, Andreas; Whitehead, Mark; Wiedner, Dirk; Wilkinson, Guy; Wilkinson, Michael; Williams, Mark Richard James; Williams, Matthew; Williams, Mike; Wilson, Fergus; Wimberley, Jack; Wishahi, Julian; Wislicki, Wojciech; Witek, Mariusz; Wormser, Guy; Wotton, Stephen; Wright, Simon; Wyllie, Kenneth; Xie, Yuehong; Xu, Zhirui; Yang, Zhenwei; Yuan, Xuhao; Yushchenko, Oleg; Zangoli, Maria; Zavertyaev, Mikhail; Zhang, Liming; Zhang, Yanxi; Zhelezov, Alexey; Zhokhov, Anatoly; Zhong, Liang

    2015-01-01

    A search for $B_s^0 \\to \\overline{D}^{0} f_{0}(980)$ decays is performed using $3.0\\, {\\rm fb}^{-1}$ of $pp$ collision data recorded by the LHCb experiment during 2011 and 2012. The $f_{0}(980)$ meson is reconstructed through its decay to the $\\pi^{+}\\pi^{-}$ final state in the mass window $900\\, {\\rm MeV}/c^{2} < m(\\pi^{+}\\pi^{-}) < 1080\\, {\\rm MeV}/c^{2}$. No significant signal is observed. The first upper limits on the branching fraction of $\\mathcal{B}(B_s^0 \\to \\overline{D}^{0} f_{0}(980)) < 3.1\\,(3.4) \\times 10^{-6}$ are set at $90\\%$ ($95\\%$) confidence level.

  4. Asymmetry of rotational catalysis of single membrane-bound F0F1-ATP synthase

    CERN Document Server

    Zarrabi, Nawid; Diez, Manuel; Graeber, Peter; Wrachtrup, Joerg; Boersch, Michael

    2007-01-01

    Synthesis of the cellular 'energy currency' ATP is catalyzed by membrane-bound F0F1-ATP synthases. The chemical reaction at three binding sites in the F1 part is coupled to proton translocation through the membrane-integrated F0 part by an internal rotation of subunits. We examined the rotary movements of the epsilon-subunit of the 'rotor' with respect to the b-subunits of the 'stator' by single-molecule fluorescence resonance energy transfer (FRET). Rotation of epsilon during ATP hydrolysis is divided into three major steps with constant FRET level corresponding to three binding sites. Different catalytic activities of the individual binding sites were observed depending on the relative orientation of the 'rotor'. Computer simulations of the FRET signals and non-equally distributed orientations of epsilon strongly corroborate asymmetry of catalysis in F0F1-ATP synthase.

  5. Antibiofilm activity of Actinobacillus pleuropneumoniae serotype 5 capsular polysaccharide.

    Directory of Open Access Journals (Sweden)

    Michael T Karwacki

    Full Text Available Cell-free extracts isolated from colony biofilms of Actinobacillus pleuropneumoniae serotype 5 were found to inhibit biofilm formation by Staphylococcus aureus, S. epidermidis and Aggregatibacter actinomycetemcomitans, but not by A. pleuropneumoniae serotype 5 itself, in a 96-well microtiter plate assay. Physical and chemical analyses indicated that the antibiofilm activity in the extract was due to high-molecular-weight polysaccharide. Extracts isolated from a mutant strain deficient in the production of serotype 5 capsular polysaccharide did not exhibit antibiofilm activity. A plasmid harboring the serotype 5 capsule genes restored the antibiofilm activity in the mutant extract. Purified serotype 5 capsular polysaccharide also exhibited antibiofilm activity against S. aureus. A. pleuropneumoniae wild-type extracts did not inhibit S. aureus growth, but did inhibit S. aureus intercellular adhesion and binding of S. aureus cells to stainless steel surfaces. Furthermore, polystyrene surfaces coated with A. pleuropneumoniae wild-type extracts, but not with capsule-mutant extracts, resisted S. aureus biofilm formation. Our findings suggest that the A. pleuropneumoniae serotype 5 capsule inhibits cell-to-cell and cell-to-surface interactions of other bacteria. A. pleuropneumoniae serotype 5 capsular polysaccharide is one of a growing number of bacterial polysaccharides that exhibit broad-spectrum, nonbiocidal antibiofilm activity. Future studies on these antibiofilm polysaccharides may uncover novel functions for bacterial polysaccharides in nature, and may lead to the development of new classes of antibiofilm agents for industrial and clinical applications.

  6. Structural studies of the O-specific polysaccharide(s) from the lipopolysaccharide of Azospirillum brasilense type strain Sp7.

    Science.gov (United States)

    Sigida, Elena N; Fedonenko, Yuliya P; Shashkov, Alexander S; Zdorovenko, Evelina L; Konnova, Svetlana A; Ignatov, Vladimir V; Knirel, Yuriy A

    2013-10-18

    Lipopolysaccharide was obtained by phenol-water extraction from dried bacterial cells of Azospirillum brasilense type strain Sp7. Mild acid hydrolysis of the lipopolysaccharide followed by GPC on Sephadex G-50 resulted in a polysaccharide mixture, which was studied by composition and methylation analyses, Smith degradation and (1)H and (13)C NMR spectroscopy. The following polysaccharide structures were established, where italics indicate a non-stoichiometric (∼40%) 2-O-methylation of l-rhamnose.

  7. Bacterial surface adaptation

    Science.gov (United States)

    Utada, Andrew

    2014-03-01

    Biofilms are structured multi-cellular communities that are fundamental to the biology and ecology of bacteria. Parasitic bacterial biofilms can cause lethal infections and biofouling, but commensal bacterial biofilms, such as those found in the gut, can break down otherwise indigestible plant polysaccharides and allow us to enjoy vegetables. The first step in biofilm formation, adaptation to life on a surface, requires a working knowledge of low Reynolds number fluid physics, and the coordination of biochemical signaling, polysaccharide production, and molecular motility motors. These crucial early stages of biofilm formation are at present poorly understood. By adapting methods from soft matter physics, we dissect bacterial social behavior at the single cell level for several prototypical bacterial species, including Pseudomonas aeruginosa and Vibrio cholerae.

  8. Structural modification of polysaccharides: A biochemical-genetic approach

    Science.gov (United States)

    Kern, Roger G.; Petersen, Gene R.

    1991-01-01

    Polysaccharides have a wide range of industrial and biomedical applications. An industry trend is underway towards the increased use of bacteria to produce polysaccharides. Long term goals of this work are the adaptation and enhancement of saccharide properties for electronic and optic applications. In this report we illustrate the application of enzyme-bearing bacteriophage on strains of the enteric bacterium Klebsiella pneumoniae, which produces a polysaccharide with the relatively rare rheological property of drag-reduction. This has resulted in the production of new polysaccharides with enhanced rheological properties. Our laboratory is developing techniques for processing and structurally modifying bacterial polysaccharides and oligosaccharides which comprise their basic polymeric repeat units. Our research has focused on bacteriophage which produce specific polysaccharide degrading enzymes. This has lead to the development of enzymes generated by bacteriophage as tools for polysaccharide modification and purification. These enzymes were used to efficiently convert the native material to uniform-sized high molecular weight polymers, or alternatively into high-purity oligosaccharides. Enzyme-bearing bacteriophage also serve as genetic selection tools for bacteria that produce new families of polysaccharides with modified structures.

  9. Statistical properties of the deviations of f 0 F 2 from monthly medians

    Directory of Open Access Journals (Sweden)

    Y. Tulunay

    2002-06-01

    Full Text Available The deviations of hourly f 0 F 2 from monthly medians for 20 stations in Europe during the period 1958-1998 are studied. Spectral analysis is used to show that, both for original data (for each hour and for the deviations from monthly medians, the deterministic components are the harmonics of 11 years (solar cycle, 1 year and its harmonics, 27 days and 12 h 50.49 m (2nd harmonic of lunar rotation period L 2 periodicities. Using histograms for one year samples, it is shown that the deviations from monthly medians are nearly zero mean (mean < 0.5 and approximately Gaussian (relative difference range between %10 to %20 and their standard deviations are larger for daylight hours (in the range 5-7. It is shown that the amplitude distribution of the positive and negative deviations is nearly symmetrical at night hours, but asymmetrical for day hours. The positive and negative deviations are then studied separately and it is observed that the positive deviations are nearly independent of R12 except for high latitudes, but negative deviations are modulated by R12 . The 90% confidence interval for negative deviations for each station and each hour is computed as a linear model in terms of R12. After correction for local time, it is shown that for all hours the confidence intervals increase with latitude but decrease above 60N. Long-term trend analysis showed that there is an increase in the amplitude of positive deviations from monthly means irrespective of the solar conditions. Using spectral analysis it is also shown that the seasonal dependency of negative deviations is more accentuated than the seasonal dependency of positive deviations especially at low latitudes. In certain stations, it is also observed that the 4th harmonic of 1 year corresponding to a periodicity of 3 months, which is missing in f 0 F 2 data, appears in the spectra of negative variations.

  10. A method for f0F2 monitoring over Spain using the El Arenosillo digisonde current observations

    Directory of Open Access Journals (Sweden)

    G. Miro

    1999-06-01

    Full Text Available Ionosphere monitoring implies: observations, prediction and mapping of ionospheric parameters. A case with one available (El Arenosillo ionosonde is considered. Some statistical methods for f0F2 short-term (1-24 h in advance prediction are compared. The analysis of multi-dimensional regression for Df0F2 (relative deviation from running median with Ap, F10.7 and previous Df0F2 observations has shown that inclusion of additional terms with Ap and F10.7 improves the prediction accuracy for lead time more than 15 h. For lead time 1-6 h a linear regression with earlier observed Df0F2 provides the f0F2 forecast with Relative Mean Deviation (RMD 6-11%. This is acceptable from a practical point of view. A 24-h forecast can be done with RMD 10-11%. Multi-regressional methods provide better prediction accuracy than the usual 10-day running median or quasi-inertial method based on such median. Hourly f0F2 values may be used to calculate the effective index R12eff used as input to the ITU-R monthly median model. This allows the ITU-R model to "breathe" following hour-to-hour f0F2 variations. Then standard surfering methods may be applied for f0F2 mapping over the whole area. The f0F2 mapping accuracy based on the hourly R12eff index is shown to be 9-11% depending on solar activity level.

  11. Starch-degrading polysaccharide monooxygenases.

    Science.gov (United States)

    Vu, Van V; Marletta, Michael A

    2016-07-01

    Polysaccharide degradation by hydrolytic enzymes glycoside hydrolases (GHs) is well known. More recently, polysaccharide monooxygenases (PMOs, also known as lytic PMOs or LPMOs) were found to oxidatively degrade various polysaccharides via a copper-dependent hydroxylation. PMOs were previously thought to be either GHs or carbohydrate binding modules (CBMs), and have been re-classified in carbohydrate active enzymes (CAZY) database as auxiliary activity (AA) families. These enzymes include cellulose-active fungal PMOs (AA9, formerly GH61), chitin- and cellulose-active bacterial PMOs (AA10, formerly CBM33), and chitin-active fungal PMOs (AA11). These PMOs significantly boost the activity of GHs under industrially relevant conditions, and thus have great potential in the biomass-based biofuel industry. PMOs that act on starch are the latest PMOs discovered (AA13), which has expanded our perspectives in PMOs studies and starch degradation. Starch-active PMOs have many common structural features and biochemical properties of the PMO superfamily, yet differ from other PMO families in several important aspects. These differences likely correlate, at least in part, to the differences in primary and higher order structures of starch and cellulose, and chitin. In this review we will discuss the discovery, structural features, biochemical and biophysical properties, and possible biological functions of starch-active PMOs, as well as their potential application in the biofuel, food, and other starch-based industries. Important questions regarding various aspects of starch-active PMOs and possible economical driving force for their future studies will also be highlighted. PMID:27170366

  12. Radiation processed polysaccharide products

    International Nuclear Information System (INIS)

    Radiation crosslinking, degradation and grafting techniques for modification of polymeric materials including natural polysaccharides have been providing many unique products. In this communication, typical products from radiation processed polysaccharides particularly plant growth promoter from alginate, plant protector and elicitor from chitosan, super water absorbent containing starch, hydrogel sheet containing carrageenan/CM-chitosan as burn wound dressing, metal ion adsorbent from partially deacetylated chitin were described. The procedures for producing those above products were also outlined. Future development works on radiation processing of polysaccharides were briefly presented. (author)

  13. An L0(F,R)-valued Function's Intermediate Value Theorem and Its Applications to Random Uniform Convexity

    Institute of Scientific and Technical Information of China (English)

    Tie Xin GUO; Xiao Lin ZENG

    2012-01-01

    Let (Ω,F,P) be a probability space and L0(F,R) the algebra of equivalence classes of realvalued random variables on (Ω,F,P).When L0(F,R) is endowed with the topology of convergence in probability,we prove an intermediate value theorem for a continuous local function from L0(F,R) to L0(F,R).As applications of this theorem,we first give several useful expressions for modulus of random convexity,then we prove that a complete random normed module (S,‖· ‖) is random uniformly convex itf LF(S) is uniformly convex for each fixed positive number p such that 1 < p < +oo.

  14. The F0F1 ATP Synthase Complex Localizes to Membrane Rafts in Gonadotrope Cells.

    Science.gov (United States)

    Allen-Worthington, Krystal; Xie, Jianjun; Brown, Jessica L; Edmunson, Alexa M; Dowling, Abigail; Navratil, Amy M; Scavelli, Kurt; Yoon, Hojean; Kim, Do-Geun; Bynoe, Margaret S; Clarke, Iain; Roberson, Mark S

    2016-09-01

    Fertility in mammals requires appropriate communication within the hypothalamic-pituitary-gonadal axis and the GnRH receptor (GnRHR) is a central conduit for this communication. The GnRHR resides in discrete membrane rafts and raft occupancy is required for signaling by GnRH. The present studies use immunoprecipitation and mass spectrometry to define peptides present within the raft associated with the GnRHR and flotillin-1, a key raft marker. These studies revealed peptides from the F0F1 ATP synthase complex. The catalytic subunits of the F1 domain were validated by immunoprecipitation, flow cytometry, and cell surface biotinylation studies demonstrating that this complex was present at the plasma membrane associated with the GnRHR. The F1 catalytic domain faces the extracellular space and catalyzes ATP synthesis when presented with ADP in normal mouse pituitary explants and a gonadotrope cell line. Steady-state extracellular ATP accumulation was blunted by coadministration of inhibitory factor 1, limiting inorganic phosphate in the media, and by chronic stimulation of the GnRHR. Steady-state extracellular ATP accumulation was enhanced by pharmacological inhibition of ecto-nucleoside triphosphate diphosphohydrolases. Kisspeptin administration induced coincident GnRH and ATP release from the median eminence into the hypophyseal-portal vasculature in ovariectomized sheep. Elevated levels of extracellular ATP augmented GnRH-induced secretion of LH from pituitary cells in primary culture, which was blocked in media containing low inorganic phosphate supporting the importance of extracellular ATP levels to gonadotrope cell function. These studies indicate that gonadotropes have intrinsic ability to metabolize ATP in the extracellular space and extracellular ATP may serve as a modulator of GnRH-induced LH secretion. PMID:27482602

  15. Evolution of the F0F1 ATP synthase complex in light of the patchy distribution of different bioenergetic pathways across prokaryotes.

    Directory of Open Access Journals (Sweden)

    Vassiliki Lila Koumandou

    2014-09-01

    Full Text Available Bacteria and archaea are characterized by an amazing metabolic diversity, which allows them to persist in diverse and often extreme habitats. Apart from oxygenic photosynthesis and oxidative phosphorylation, well-studied processes from chloroplasts and mitochondria of plants and animals, prokaryotes utilize various chemo- or lithotrophic modes, such as anoxygenic photosynthesis, iron oxidation and reduction, sulfate reduction, and methanogenesis. Most bioenergetic pathways have a similar general structure, with an electron transport chain composed of protein complexes acting as electron donors and acceptors, as well as a central cytochrome complex, mobile electron carriers, and an ATP synthase. While each pathway has been studied in considerable detail in isolation, not much is known about their relative evolutionary relationships. Wanting to address how this metabolic diversity evolved, we mapped the distribution of nine bioenergetic modes on a phylogenetic tree based on 16S rRNA sequences from 272 species representing the full diversity of prokaryotic lineages. This highlights the patchy distribution of many pathways across different lineages, and suggests either up to 26 independent origins or 17 horizontal gene transfer events. Next, we used comparative genomics and phylogenetic analysis of all subunits of the F0F1 ATP synthase, common to most bacterial lineages regardless of their bioenergetic mode. Our results indicate an ancient origin of this protein complex, and no clustering based on bioenergetic mode, which suggests that no special modifications are needed for the ATP synthase to work with different electron transport chains. Moreover, examination of the ATP synthase genetic locus indicates various gene rearrangements in the different bacterial lineages, ancient duplications of atpI and of the beta subunit of the F0 subcomplex, as well as more recent stochastic lineage-specific and species-specific duplications of all subunits. We

  16. Structure of the polysaccharides from the lipopolysaccharide of Azospirillum brasilense Jm125A2.

    Science.gov (United States)

    Sigida, Elena N; Fedonenko, Yuliya P; Shashkov, Alexander S; Zdorovenko, Evelina L; Konnova, Svetlana A; Ignatov, Vladimir V; Knirel, Yuriy A

    2015-10-30

    Two polysaccharides were obtained by mild acid degradation of the lipopolysaccharide of associative nitrogen-fixing bacteria Azospirillum brasilense Jm125A2 isolated from the rhizosphere of a pearl millet. The following structures of the polysaccharides were established by sugar and methylation analyses, Smith degradation, and (1)H and (13)C NMR spectroscopy: [Formula: see text] Structure 1 has been reported earlier for a polysaccharide from A. brasilense S17 (Fedonenko YP, Konnova ON, Zdorovenko EL, Konnova SA, Zatonsky GV, Shaskov AS, Ignatov VV, Knirel YA. Carbohydr Res 2008;343:810-6), whereas to our knowledge structure 2 has not been hitherto found in bacterial polysaccharides.

  17. Structure of even- and odd-A 1p0f-shell nuclei in the collective pair approximation

    International Nuclear Information System (INIS)

    The structure of A = 59-62 nuclei has been studied in the framework of the collective pair approximation. The collective pairs, determined by diagonalizing the shell-model Hamiltonian in the space of two valence nucleons occupying the 1p1/2, 1p3/2 and 0f5/2 subshells above the closed subshell 0f7/2 of the 1p0f shell, have been considered as building blocks to describe nuclei with 2n or 2n + 1 valence nucleons in terms of n pairs or n pairs coupled with one nucleon, respectively. It is shown that the low-lying spectra of A = 59-62 nuclei can be described quite well by considering only a selected subset of all possible collective pairs

  18. DECOMPOSITION AND BINDING ACTION OF A POLYSACCHARIDE FROM CHROMOBACTERIUM VIOLACIUM IN SOIL.

    Science.gov (United States)

    MARTIN, J P; RICHARDS, S J

    1963-06-01

    Martin, J. P. (University of California, Riverside) and S. J. Richards. Decomposition and binding action of a polysaccharide from Chromobacterium violaceum in soil. J. Bacteriol. 85:1288-1294. 1963.-The decomposition rate and binding effect in soil of a polysaccharide from Chromobacterium violaceum was compared with that of a variety of bacterial and plant polysaccharides and more complex organic residues. Most of the polysaccharides tested decomposed more readily than mature plant residues and fungus mycelium. The ease of decomposition varied, however, and polysaccharide from C. violaceum over a period of 1 month was more resistant than corn stalks, Rhodes grass, bean straw, and orange leaves. During the first week, it was as resistant to decay as pine needles. The C. violaceum polysaccharide was more effective in binding or aggregating the soil than all others tested. It also reduced the bulk density of Greenfield sandy loam and increased hydraulic conductivity in neutral soil. PMID:14047219

  19. Antibacterial and antiviral study of dialdehyde polysaccharides

    Science.gov (United States)

    Song, Le

    Concerns for microbial contamination and infection to the general population, especially the spread of drug-resistant microorganisms, have greatly increased. Polymeric biocides have been found to be a feasible strategy to inactivate drug-resistant bacteria. However, current polymeric biocide systems involve multi-step chemical reactions and they are not cost-effective. Desirable antimicrobial systems need to be designed to be environmentally friendly, broad-spectrum effective against microorganisms, flexible for various delivery methods and economically affordable. We demonstrated that dialdehyde polysaccharides (including dialdehyde starch and dialdehdye cellulose) were broad-spectrum polymeric biocides against gram-positive/negative bacteria, bacteriophages and human virus. These polymers can be easily converted from starch and cellulose through one-step periodate oxidation. Destructions of microorganism by dialdehyde polysaccharides have been achieved in aqueous suspension or by solid surface contact. The dialdehdye functions of dialdehdye polysaccharides were found to be the dominant action against microorganism. The reactivity of the dialdehyde functionality was found to be pH-dependent as well as related to the dispersion of dialdehyde polysaccharides. Degradation of dialdehyde starch during cooking was confirmed. Degradation of dialdehyde starch was more liable in alkaline condition. Carboxylic acid and conjugated aldehyde functionalities were the two main degradation products, confirmed from the spectroscopic studies. The pH effect on the polysaccharide structure and the corresponding antimicrobial activity was very complicated. No decisive conclusions could be obtained from this study. Liner inactivation kinetics was found for dialdehyde starch aqueous suspension against bacteria. This linear inactivation kinetics was derived from the pseudo-first chemical reaction between the dialdehyde starch and the bacteria. The established inactivation kinetics was

  20. Iron oxyhydroxide mineralization on microbial extracellular polysaccharides

    Energy Technology Data Exchange (ETDEWEB)

    Chan, Clara S.; Fakra, Sirine C.; Edwards, David C.; Emerson, David; Banfield, Jillian F.

    2010-06-22

    Iron biominerals can form in neutral pH microaerophilic environments where microbes both catalyze iron oxidation and create polymers that localize mineral precipitation. In order to classify the microbial polymers that influence FeOOH mineralogy, we studied the organic and mineral components of biominerals using scanning transmission X-ray microscopy (STXM), micro X-ray fluorescence ({mu}XRF) microscopy, and high-resolution transmission electron microscopy (HRTEM). We focused on iron microbial mat samples from a creek and abandoned mine; these samples are dominated by iron oxyhydroxide-coated structures with sheath, stalk, and filament morphologies. In addition, we characterized the mineralized products of an iron-oxidizing, stalk-forming bacterial culture isolated from the mine. In both natural and cultured samples, microbial polymers were found to be acidic polysaccharides with carboxyl functional groups, strongly spatially correlated with iron oxyhydroxide distribution patterns. Organic fibrils collect FeOOH and control its recrystallization, in some cases resulting in oriented crystals with high aspect ratios. The impact of polymers is particularly pronounced as the materials age. Synthesis experiments designed to mimic the biomineralization processes show that the polysaccharide carboxyl groups bind dissolved iron strongly but release it as mineralization proceeds. Our results suggest that carboxyl groups of acidic polysaccharides are produced by different microorganisms to create a wide range of iron oxyhydroxide biomineral structures. The intimate and potentially long-term association controls the crystal growth, phase, and reactivity of iron oxyhydroxide nanoparticles in natural systems.

  1. Absolute frequency measurement of 1S0 (F = 1/2) - 3P0 (F = 1/2) transition of 171Yb atoms in a one-dimensional optical lattice at KRISS

    CERN Document Server

    Park, Chang Yong; Lee, Won-Kyu; Park, Sang Eon; Kim, Eok Bong; Lee, Sun Kyung; Cho, Jun Woo; Yoon, Tai Hyun; Mun, Jongchul; Park, Sung Jong; Kwon, Taeg Yong; Lee, Sang-Bum

    2011-01-01

    We measured the absolute frequency of the optical clock transition 1S0 (F = 1/2) - 3P0 (F = 1/2) of 171Yb atoms confined in a one-dimensional optical lattice and it was determined to be 518 295 836 590 865.7 (9.2) Hz. The measured frequency was calibrated to the Coordinated Universal Time (UTC) by using an optical frequency comb of which frequency was phase-locked to a hydrogen maser as a flywheel oscillator traceable to the UTC. The magic wavelength was also measured as 394 798.48 (79) GHz. The results are in good agreement with two previous measurements of other institutes within the specified uncertainty of this work.

  2. Observation of the isospin-violating decay $J/\\psi \\to \\phi\\pi^{0}f_{0}(980)$

    CERN Document Server

    Ablikim, M; Ai, X C; Albayrak, O; Albrecht, M; Ambrose, D J; Amoroso, A; An, F F; An, Q; Bai, J Z; Ferroli, R Baldini; Ban, Y; Bennett, D W; Bennett, J V; Bertani, M; Bettoni, D; Bian, J M; Bianchi, F; Boger, E; Bondarenko, O; Boyko, I; Briere, R A; Cai, H; Cai, X; Cakir, O; Calcaterra, A; Cao, G F; Cetin, S A; Chang, J F; Chelkov, G; Chen, G; Chen, H S; Chen, H Y; Chen, J C; Chen, M L; Chen, S J; Chen, X; Chen, X R; Chen, Y B; Cheng, H P; Chu, X K; Cibinetto, G; Cronin-Hennessy, D; Dai, H L; Dai, J P; Dbeyssi, A; De dovich, D; Deng, Z Y; Denig, A; Denysenko, I; Destefanis, M; De Mori, F; Ding, Y; Dong, C; Dong, J; Dong, L Y; Dong, M Y; Du, S X; Duan, P F; Fan, J Z; Fang, J; Fang, S S; Fang, X; Fang, Y; Fava, L; Feldbauer, F; Felici, G; Feng, C Q; Fioravanti, E; Fritsch, M; Fu, C D; Gao, Q; Gao, X Y; Gao, Y; Gao, Z; Garzia, I; Geng, C; Goetzen, K; Gong, W X; Gradl, W; Greco, M; Gu, M H; Gu, Y T; Guan, Y H; Guo, A Q; Guo, L B; Guo, Y; Guo, Y P; Haddadi, Z; ner, A Haf; Han, S; Han, Y L; Hao, X Q; Harris, F A; He, K L; He, Z Y; Held, T; Heng, Y K; Hou, Z L; Hu, C; Hu, H M; Hu, J F; Hu, T; Hu, Y; Huang, G M; Huang, G S; Huang, H P; Huang, J S; Huang, X T; Huang, Y; Hussain, T; Ji, Q; Ji, Q P; Ji, X B; Ji, X L; Jiang, L L; Jiang, L W; Jiang, X S; Jiao, J B; Jiao, Z; Jin, D P; Jin, S; ansson, T Joh; Julin, A; Kalantar-Nayestanaki, N; Kang, X L; Kang, X S; Kavatsyuk, M; Ke, B C; Kliemt, R; Kloss, B; Kolcu, O B; Kopf, B; Kornicer, M; Kuehn, W; Kupsc, A; Lange, J S; Lara, M; Larin, P; Leng, C; Li, C H; Li, Cheng; Li, D M; Li, F; Li, G; Li, H B; Li, J C; Li, Jin; Li, K; Li, Lei; Li, P R; Li, T; Li, W D; Li, W G; Li, X L; Li, X M; Li, X N; Li, X Q; Li, Z B; Liang, H; Liang, Y F; Liang, Y T; Liao, G R; Lin, D X; Liu, B J; iu, C X L; Liu, F H; Liu, Fang; Liu, Feng; Liu, H B; Liu, H H; Liu, H M; Liu, J; Liu, J P; Liu, J Y; Liu, K; Liu, K Y; Liu, L D; Liu, P L; Liu, Q; Liu, S B; Liu, X; Liu, X X; Liu, Y B; Liu, Z A; Liu, Zhiqiang; u, Zhiqing Li; Loehner, H; Lou, X C; Lu, H J; Lu, J G; Lu, R Q; Lu, Y; Lu, Y P; Luo, C L; Luo, M X; Luo, T; Luo, X L; Lv, M; Lyu, X R; Ma, F C; Ma, H L; Ma, L L; Ma, Q M; Ma, T; Ma, X N; Ma, X Y; Maas, F E; Maggiora, M; ik, Q A Mal; Mao, Y J; Mao, Z P; Marcello, S; Messchendorp, J G; Min, J; Min, T J; Mitchell, R E; Mo, X H; Mo, Y J; Morales, C Morales; Moriya, K; Muchnoi, N Yu; Muramatsu, H; Nefedov, Y; Nerling, F; Nikolaev, I B; Ning, Z; Nisar, S; Niu, S L; Niu, X Y; Olsen, S L; Ouyang, Q; Pacetti, S; Patteri, P; Pelizaeus, M; Peng, H P; Peters, K; son, J Petters; Ping, J L; Ping, R G; Poling, R; Prasad, V; Pu, Y N; Qi, M; Qian, S; Qiao, C F; Qin, L Q; Qin, N; Qin, X S; Qin, Y; Qin, Z H; Qiu, J F; Rashid, K H; Redmer, C F; Ren, H L; Ripka, M; Rong, G; Rosner, Ch; Ruan, X D; Santoro, V; Sarantsev, A; Savrié, M; Schoenning, K; Schumann, S; Shan, W; Shao, M; Shen, C P; Shen, P X; Shen, X Y; Sheng, H Y; Song, W M; Song, X Y; Sosio, S; Spataro, S; Sun, G X; Sun, J F; Sun, S S; Sun, Y J; Sun, Y Z; Sun, Z J; Sun, Z T; Tang, C J; Tang, X; Tapan, I; Thorndike, E H; Tiemens, M; Toth, D; Ullrich, M; Uman, I; arner, G S V; Wang, B; Wang, B L; Wang, D; Wang, D Y; Wang, K; Wang, L L; Wang, L S; Wang, M; Wang, P; Wang, P L; Wang, S G; Wang, W; Wang, X F; Wang, Y D; Wang, Y F; Wang, Y Q; Wang, Z; Wang, Z G; Wang, Z H; Wang, Z Y; r, T Webe; Wei, D H; Wei, J B; Weidenkaff, P; Wen, S P; Wiedner, U; Wolke, M; Wu, L H; Wu, Z; Xia, L G; Xia, Y; Xiao, D; Xiao, Z J; Xie, Y G; Xiu, Q L; Xu, G F; Xu, L; Xu, Q J; Xu, Q N; Xu, X P; Yan, L; Yan, W B; Yan, W C; Yan, Y H; Yang, H X; Yang, L; Yang, Y; Yang, Y X; Ye, H; Ye, M; Ye, M H; Yin, J H; Yu, B X; Yu, C X; Yu, H W; Yu, J S; Yuan, C Z; Yuan, W L; Yuan, Y; Yuncu, A; Zafar, A A; Zallo, A; Zeng, Y; Zhang, B X; Zhang, B Y; Zhang, C; Zhang, C C; Zhang, D H; Zhang, H H; Zhang, H Y; Zhang, J J; Zhang, J L; Zhang, J Q; Zhang, J W; Zhang, J Y; Zhang, J Z; Zhang, K; Zhang, L; Zhang, S H; Zhang, X Y; Zhang, Y; Zhang, Y H; Zhang, Y T; Zhang, Z H; Zhang, Z P; Zhang, Z Y; Zhao, G; Zhao, J W; Zhao, J Y; Zhao, J Z; Zhao, Lei; Zhao, Ling; Zhao, M G; Zhao, Q; Zhao, Q W; Zhao, S J; Zhao, T C; Zhao, Y B; Zhao, Z G; Zhemchugov, A; Zheng, B; Zheng, J P; Zheng, W J; Zheng, Y H; Zhong, B; Zhou, L; Zhou, Li; Zhou, X; Zhou, X K; Zhou, X R; Zhou, X Y; Zhu, K; Zhu, K J; Zhu, S; Zhu, X L; Zhu, Y C; Zhu, Y S; Zhu, Z A; Zhuang, J; Zotti, L; Zou, B S; Zou, J H

    2015-01-01

    Using a sample of 1.31 billion $J/\\psi$ events collected with the BESIII detector at the BEPCII collider, the decays $J/\\psi \\to \\phi \\pi^{+}\\pi^{-}\\pi^{0}$ and $J/\\psi \\to \\phi \\pi^{0}\\pi^{0}\\pi^{0}$ are investigated. The isospin violating decay $J/\\psi \\to \\phi \\pi^{0} f_{0}(980)$ with $f_{0}(980) \\to \\pi\\pi$, is observed for the first time. The width of the $f_{0}(980)$ obtained from the dipion mass spectrum is found to be much smaller than the world average value. In the $\\pi^{0} f_{0}(980)$ mass spectrum, there is evidence of $f_1(1285)$ production. By studying the decay $J/\\psi \\to \\phi\\eta'$, the branching fractions of $\\eta' \\to \\pi^{+}\\pi^{-}\\pi^{0}$ and $\\eta' \\to \\pi^{0}\\pi^{0}\\pi^{0}$, as well as their ratio, are also measured.

  3. Geomagnetic modification of the mid-latitude ionosphere - Toward a strategy for the improved forecasting of f0F2

    Science.gov (United States)

    Wrenn, G. L.; Rodger, A. S.

    1989-02-01

    An approach for modeling and forecasting the interspatial critical frequency (f0F2) at quiet and disturbed times is outlined. Statistical analyses of ionosonde data from the Argentine Islands (65 deg S) are used to define patterns for the main phase effects of midlatitude ionospheric storms. Extended to a number of stations, these could be incorporated into algorithms to permit the forecasting of maximum usable frequency for a few hours ahead and enhance the frequency management of shortwave radio communication, especially during a geomagnetic storm. Data from a complete solar cycle, 1971-1981, are used to determine the errors in the forecasts and to demonstrate that a useful advantage can be attained by this method. The rms error in f0F2 for 90,175 samples is 15.6 percent, which compares favorably with those obtained using forecasts based on quiet time values (20.4 percent) or the previous day's measurements (18 percent).

  4. Effect of pH values on the extracellular polysaccharide secreted by Acidithiobacillus ferrooxidans during chalcopyrite bioleaching

    Institute of Scientific and Technical Information of China (English)

    Run-lan Yu; Jing Liu; Jian-xi Tan; Wei-min Zeng; Li-juan Shi; Guo-hua Gu; Wen-qing Qin; Guan-zhou Qiu

    2014-01-01

    The pH value plays an important role in the bioleaching of sulphide minerals. The effect of pH values on the extracellular poly-saccharide secreted by Acidithiobacillus ferrooxidans was investigated in different phases of bacterial growth during chalcopyrite bioleach-ing. It is found that extracellular polysaccharide secretion from the cells attached to chalcopyrite is more efficiently than that of the free cells in the bioleaching solution. Three factors, pH values, the concentration of soluble metal ions, and the bacterial growth and metabolism, affect extracellular polysaccharide secretion in the free cells, and are related to the bacterial growth phase. Extracellular polysaccharide secretion from the attached cells is mainly dependent on the pH value of the bacterial culture.

  5. Effect of pH values on the extracellular polysaccharide secreted by Acidithiobacillus ferrooxidans during chalcopyrite bioleaching

    Science.gov (United States)

    Yu, Run-lan; Liu, Jing; Tan, Jian-xi; Zeng, Wei-min; Shi, Li-juan; Gu, Guo-hua; Qin, Wen-qing; Qiu, Guan-zhou

    2014-04-01

    The pH value plays an important role in the bioleaching of sulphide minerals. The effect of pH values on the extracellular polysaccharide secreted by Acidithiobacillus ferrooxidans was investigated in different phases of bacterial growth during chalcopyrite bioleaching. It is found that extracellular polysaccharide secretion from the cells attached to chalcopyrite is more efficiently than that of the free cells in the bioleaching solution. Three factors, pH values, the concentration of soluble metal ions, and the bacterial growth and metabolism, affect extracellular polysaccharide secretion in the free cells, and are related to the bacterial growth phase. Extracellular polysaccharide secretion from the attached cells is mainly dependent on the pH value of the bacterial culture.

  6. Visible Thrombolysis Acceleration of a Nanomachine Powered by Light-Driving F0F1-ATPase Motor

    Science.gov (United States)

    Duan, Xiaoxia; Liu, Lifeng; Jiang, Weijian; Yue, Jiachang

    2015-05-01

    We report on thrombolysis acceleration of a nanomachine powered by light-driving δ-subunit-free F0F1-ATPase motor. It is composed of a mechanical device, locating device, energy storage device, and propeller. The rotory δ-subunit-free F0F1-ATPase motor acts as a mechanical device, which was obtained by reconstructing an original chromatophore extracted from Rhodospirillum rubrum. We found that the bioactivity of the F0F1-ATPase motor improved greatly after reconstruction. The zeta potential of the nanomachine is about -23.4 mV. Cytotoxicity induced by the nanomachine was measured using cell counting kit (CCK)-8 assay. The A549 cells incubated with different fractional concentrations of the nanomachine within 48 h did not show obvious cytotoxicity. The locating device helps the nanomachine bind to the thrombi. Energy was easily stored by exposing the nanomachine to 600-nm-wavelength irradiation, which promoted activity of the motor. The rotation of the long propeller accelerated thrombolysis of a blood clot in vitro in the presence of urokinase (UK). This result was based on visual inspection and confirmed by a series of tests.

  7. Structural studies of the polysaccharides from the lipopolysaccharides of Azospirillum brasilense Sp246 and SpBr14.

    Science.gov (United States)

    Sigida, Elena N; Fedonenko, Yuliya P; Shashkov, Alexander S; Grinev, Vyacheslav S; Zdorovenko, Evelina L; Konnova, Svetlana A; Ignatov, Vladimir V; Knirel, Yuriy A

    2014-10-29

    Lipopolysaccharides from closely related Azospirillum brasilense strains, Sp246 and SpBr14, were obtained by phenol-water extraction. Mild acid hydrolysis of the lipopolysaccharides followed by GPC on Sephadex G-50 resulted in polysaccharide mixtures. On the basis of sugar and methylation analyses, Smith degradation and (1)H and (13)C NMR spectroscopy data, it was concluded that both bacteria possess the same two distinct polysaccharides having structures 1 and 2: [structure: see text]. Structure 1 has been reported earlier for a polysaccharide of A. brasilense 54 [Fedonenko et al., 2011] whereas to our knowledge structure 2 has not been hitherto found in bacterial polysaccharides.

  8. Illustration of Pneumococcal Polysaccharide Capsule during Adherence and Invasion of Epithelial Cells

    OpenAIRE

    Hammerschmidt, Sven; Wolff, Sonja; Hocke, Andreas; Rosseau, Simone; Müller, Ellruth; Rohde, Manfred

    2005-01-01

    The capsular polysaccharide of Streptococcus pneumoniae represents an important virulence factor and protects against phagocytosis. In this study the amount of capsular polysaccharide present on the bacterial surface during the infection process was illustrated by electron microscopic studies. After infection of A549 cells (type II pneumocytes) and HEp-2 epithelial cells a modified fixation method was used that allowed visualization of the state of capsule expression. This modified fixation p...

  9. CHINESE 0F HUMANITY

    Institute of Scientific and Technical Information of China (English)

    2011-01-01

    How to Improve Your Oral English by "Listening, Speaking, Reading and Writing" Abstract:the learning of oral Englisn becomes and more important in the 21st century. The essay probes in to the relationship between oral English and listening, reading and writing, and put forward the method to improve oral English by listening, speaking, reading and writing.

  10. Effects of solution conditions on characteristics and size exclusion chromatography of pneumococcal polysaccharides and conjugate vaccines.

    Science.gov (United States)

    Hadidi, Mahsa; Buckley, John J; Zydney, Andrew L

    2016-11-01

    Molecular properties of bacterial polysaccharides and protein-polysaccharide conjugates play an important role in the efficiency and immunogenicity of the final vaccine product. Size exclusion chromatography (SEC) is commonly used to analyze and characterize biopolymers, including capsular polysaccharides. The objective of this work was to determine the effects of solution ionic strength and pH on the SEC retention of several capsular polysaccharides from S. pneumoniae bacteria in their native and conjugated forms. The retention time of the charged polysaccharides increased with increasing ionic strength and decreasing pH due to compaction of the polysaccharides associated with a reduction in the intramolecular electrostatic interactions. The calculated radius of gyration was in good agreement with model calculations based on the worm-like chain model accounting for the increase in chain stiffness and excluded volume of the charged polysaccharide at low ionic strength. These results provide important insights into the effects of solution ionic strength on physical properties and SEC behavior of capsular polysaccharides and their corresponding conjugates. PMID:27516244

  11. Why Were Polysaccharides Necessary?

    Science.gov (United States)

    Tolstoguzov, Vladimir

    2004-12-01

    The main idea of this paper is that the primordial soup may be modelled by food systems whose structure-property relationship is based on non-specific interactions between denatured biopolymers. According to the proposed hypothesis, polysaccharides were the first biopolymers that decreased concentration of salts in the primordial soup, `compatibilised' and drove the joint evolution of proto-biopolymers. Synthesis of macromolecules within the polysaccharide-rich medium could have resulted in phase separation of the primordial soup and concentration of the polypeptides and nucleic acids in the dispersed phase particles. The concentration of proto-biopolymer mixtures favoured their cross-linking in hybrid supermacromolecules of conjugates. The cross-linking of proto-biopolymers could occur by hydrophobic, electrostatic interactions, H-bonds due to freezing aqueous mixed biopolymer dispersions and/or by covalent bonds due to the Maillard reaction. Cross-linking could have increased the local concentration of chemically different proto-biopolymers, fixed their relative positions and made their interactions reproducible. Attractive-repulsive interactions between cross-linked proto-biopolymer chains could develop pairing of the monomer units, improved chemical stability (against hydrolysis) and led to their mutual catalytic activity and coding. Conjugates could probably evolve to the first self-reproduced entities and then to specialized cellular organelles. Phase separation of the primordial soup with concentration of conjugates in the dispersed particles has probably resulted in proto-cells.

  12. Tn5401 disruption of the spo0F gene, identified by direct chromosomal sequencing, results in CryIIIA overproduction in Bacillus thuringiensis.

    OpenAIRE

    Malvar, T.; Baum, J A

    1994-01-01

    The Bacillus thuringiensis spo0F gene was identified by chromosomal DNA sequencing of sporulation mutants derived from a B. thuringiensis transposon insertion library. A spo0F defect in B. thuringiensis, which was suppressed by multicopy hknA or kinA, resulted in the overproduction of the CryIIIA insecticidal crystal protein.

  13. Polysaccharides: Molecular and Supramolecular Structures. Terminology.

    NARCIS (Netherlands)

    Heinze, Thomas; Petzold-Welcke, Katrin; Dam, van J.E.G.

    2012-01-01

    This chapter summarises important issues
    about the molecular and supramolecular structure
    of polysaccharides. It describes the terminology
    of polysaccharides systematically. The
    polysaccharides are divided regarding the
    molecular structures in glucans, polyoses,
    polysaccharid

  14. Characterization of the Kingella kingae polysaccharide capsule and exopolysaccharide.

    Directory of Open Access Journals (Sweden)

    Kimberly F Starr

    Full Text Available Recent evidence indicates that Kingella kingae produces a polysaccharide capsule. In an effort to determine the composition and structure of this polysaccharide capsule, in the current study we purified capsular material from the surface of K. kingae strain 269-492 variant KK01 using acidic conditions to release the capsule and a series of steps to remove DNA, RNA, and protein. Analysis of the resulting material by gas chromatography and mass spectrometry revealed N-acetyl galactosamine (GalNAc, 3-deoxy-D-manno-oct-2-ulosonic acid (Kdo, and galactose (Gal. Further analysis by NMR demonstrated two distinct polysaccharides, one consisting of GalNAc and Kdo with the structure →3-β-GalpNAc-(1→5-β-Kdop-(2→ and the other containing galactose alone with the structure →5-β-Galf-(1→. Disruption of the ctrA gene required for surface localization of the K. kingae polysaccharide capsule resulted in elimination of GalNAc and Kdo but had no effect on the presence of Gal in bacterial surface extracts. In contrast, deletion of the pamABCDE locus involved in production of a reported galactan exopolysaccharide eliminated Gal but had no effect on the presence of GalNAc and Kdo in surface extracts. Disruption of ctrA and deletion of pamABCDE resulted in a loss of all carbohydrates in surface extracts. These results establish that K. kingae strain KK01 produces a polysaccharide capsule with the structure →3-β-GalpNAc-(1→5-β-Kdop-(2→ and a separate exopolysaccharide with the structure →5-β-Galf-(1→. The polysaccharide capsule and the exopolysaccharide require distinct genetic loci for surface localization.

  15. Analysis of LOFT pressurizer spray and surge nozzles to include a 450/sup 0/F step transient

    Energy Technology Data Exchange (ETDEWEB)

    Nitzel, M.E.

    1978-01-18

    This report presents the analysis of the LOFT pressurizer spray and surge nozzles to include a 450/sup 0/F step thermal transient. Previous analysis performed under subcontract by Basic Technology Incorporated was utilized where applicable. The SAASIII finite element computer program was used to determine stress distributions in the nozzles due to the step transient. Computer results were then incorporated in the necessary additional calculations to ascertain that stress limitations were not exceeded. The results of the analysis indicate that both the spray and surge nozzles will be within stress allowables prescribed by subsubarticle NB-3220 of the 1974 edition of the ASME Boiler and Pressure Vessel Code when subjected to currently known design, normal operating, upset, emergency, and faulted condition loads.

  16. Polysaccharide production and biofilm formation by Pseudomonas fluorescens : effects of pH and surface material

    OpenAIRE

    Oliveira, Rosário; Melo, L. F.; de Oliveira, A.; Salgueiro, R.

    1994-01-01

    Although the synthesis of extracellular polysaccharides has been recognized in certain bacterial cultures since a long time ago, its role in bacterial adhesion is still subject to some debate. Several fermentation batch cultures were performed at different conditions of pH (pH 7 and pH 8, maintained with NaOH and HCl, pH 7 phosphate buffer, and without pH control) in order to study the relation between the production of extracellular polysaccharides and biofilm formation ...

  17. A threading receptor for polysaccharides

    Science.gov (United States)

    Mooibroek, Tiddo J.; Casas-Solvas, Juan M.; Harniman, Robert L.; Renney, Charles M.; Carter, Tom S.; Crump, Matthew P.; Davis, Anthony P.

    2016-01-01

    Cellulose, chitin and related polysaccharides are key renewable sources of organic molecules and materials. However, poor solubility tends to hamper their exploitation. Synthetic receptors could aid dissolution provided they are capable of cooperative action, for example by multiple threading on a single polysaccharide molecule. Here we report a synthetic receptor designed to form threaded complexes (polypseudorotaxanes) with these natural polymers. The receptor binds fragments of the polysaccharides in aqueous solution with high affinities (Ka up to 19,000 M-1), and is shown—by nuclear Overhauser effect spectroscopy—to adopt the threading geometry. Evidence from induced circular dichroism and atomic force microscopy implies that the receptor also forms polypseudorotaxanes with cellulose and its polycationic analogue chitosan. The results hold promise for polysaccharide solubilization under mild conditions, as well as for new approaches to the design of biologically active molecules.

  18. 生物纤维素及其与多糖共混纤维的结构与性能%Structure and Properties of Bacterial Cellulose Fibers and Their Blend Fibers with Polysaccharide

    Institute of Scientific and Technical Information of China (English)

    王辉; 王怀芳; 张传杰; 朱平

    2012-01-01

    以生物纤维素、海藻酸和壳聚糖为原料,离子液体为溶剂,采用湿法纺丝工艺,制备了生物纤维素纤维、生物纤维素/海藻酸共混纤维和生物纤维素/壳聚糖共混纤维,研究了纤维的SEM形貌、红外光谱、力学性能、吸湿性、染色性能和抗菌性能。结果表明:纤维粗细均匀,且纵向表面光滑,无裂纹,截面近似为圆形;三种纤维的断裂强度在3.0cN/dtex左右,接近棉纤维,比粘胶纤维好很多;三种纤维的吸湿性能均比较优异,远优于棉纤维,其中生物纤维素/海藻酸共混纤维的吸湿性最佳,其次是生物纤维素/壳聚糖共混纤维;生物纤维素/壳聚糖复合纤维的抗菌效果明显且抗菌持久性好,经过15次洗涤之后,对大肠杆菌和金黄色葡萄球菌的抑菌率仍然大于90%,具有良好的抗菌效果。%Bacterial cellulose (BC), bacterial cellulose / alginic acid blend fibers (BC / ALG) and bacterial cellulose / chitosan blend fibers (BC / CS) were prepared using wet spinning process with bacterial cellulose, alginic acid and chitosan as raw materials and ionic liquid as solvent. The structure of these three fibers was characterized by FT-IR and SEM, while their physical properties, absorbing liquid capacity, dying performance and antibacterial properties were measured in this paper. These three fibers had uniform thickness, approximate circular cross-section and smooth longitudinal surface without crack structure. Their breaking strength was above 3.0 cN/dtex, which was close to cotton fibers' but higher than viscose fibers'. Moisture absorption performance of these fibers was more outstanding and it was much better than cotton fibers. But it was poorer than calcium alginate fibers' moisture absorption capacity, especially of solution A which imitated the wound exudates. Antibacterial effect of BC / CS fibers was obvious and their antibacterial durability was good

  19. Computer simulation and experimental study of the polysaccharide-polysaccharide interaction in the bacteria Azospirillum brasilense Sp245

    Science.gov (United States)

    Arefeva, Oksana A.; Kuznetsov, Pavel E.; Tolmachev, Sergey A.; Kupadze, Machammad S.; Khlebtsov, Boris N.; Rogacheva, Svetlana M.

    2003-09-01

    We have studied the conformational properties and molecular dynamics of polysaccharides by using molecular modeling methods. Theoretical and experimental results of polysaccharide-polysaccharide interactions are described.

  20. Simultaneous determination of neutral sugars and uronic acid constituents in a novel bacterial polysaccharide using gas chromatography-mass spectrometry%气相色谱-质谱联用同时分析新型细菌多糖中的单糖和糖醛酸

    Institute of Scientific and Technical Information of China (English)

    王凤芹; 杨航仙; 汪以真

    2013-01-01

    对纯化的新型细菌多糖进行酸水解,用乙硫醇-三氟乙酸和醋酐-吡啶体系先后对酸水解物进行衍生,与之前报道不同的是糖醛酸得到有效衍生化.以木糖为内标,采用气相色谱-质谱联用(GC-MS)定量分析该多糖酸水解物中单糖和糖醛酸衍生物发现,该多糖的糖链由岩藻糖、葡萄糖、葡萄糖醛酸和半乳糖组成,其相对物质的量比为1.50∶1.0∶0.79∶2.06;中性糖比例与糖醇乙酸酯化分析岩藻糖、葡萄糖和半乳糖的相对物质的量比(1.76∶1.0∶1.98)接近;糖醛酸咔唑法与该方法分析葡萄糖醛酸的含量分别为16.19%和14.85%.以上结果表明所建立的衍生化方法及GC-MS同时定量分析多糖酸水解物中单糖和糖醛酸的方法可行.此外还对葡萄糖醛酸的质谱裂解机理进行了阐述.%The purified novel bacterial polysaccharide was acid-hydrolyzed, followed by the subsequent derivatization using ethanethiol-trifluoroacetic acid and acetic anhydride-pyridine systems sequentially. Our findings differ from the previous reports in that the glucuronic acid was obtained through effective derivatization. The neutral sugars and glucuronic acid were analyzed using gas chromatography-mass spectrometry (GC-MS) with xylose as an internal standard. The polysaccharide was found to be composed of fucose, glucose, glucuronic acid and galactose, with the relative molar ratio of 1. 50: 1. 0: 0. 79= 2. 06. The neutral sugars ratio was similar to the relative molar ratio for fucose, glucose and galactose of 1. 76: l. 0: 1. 98 through alditol acetates determined by GC. The percentages of glucuronic acid analyzed using either the carbazole and sulfuric acid method or the above method were 16. 19% and 14. 85%, respectively. These results indicate that it is practicable to use the derivatization method and GC-MS to quantitatively analyze neutral sugars and glucuronic acid simultaneously in polysaccharide. For GC-MS analysis, the

  1. Polysaccharide degradation systems of the saprophytic bacterium Cellvibrio japonicus.

    Science.gov (United States)

    Gardner, Jeffrey G

    2016-07-01

    Study of recalcitrant polysaccharide degradation by bacterial systems is critical for understanding biological processes such as global carbon cycling, nutritional contributions of the human gut microbiome, and the production of renewable fuels and chemicals. One bacterium that has a robust ability to degrade polysaccharides is the Gram-negative saprophyte Cellvibrio japonicus. A bacterium with a circuitous history, C. japonicus underwent several taxonomy changes from an initially described Pseudomonas sp. Most of the enzymes described in the pre-genomics era have also been renamed. This review aims to consolidate the biochemical, structural, and genetic data published on C. japonicus and its remarkable ability to degrade cellulose, xylan, and pectin substrates. Initially, C. japonicus carbohydrate-active enzymes were studied biochemically and structurally for their novel polysaccharide binding and degradation characteristics, while more recent systems biology approaches have begun to unravel the complex regulation required for lignocellulose degradation in an environmental context. Also included is a discussion for the future of C. japonicus as a model system, with emphasis on current areas unexplored in terms of polysaccharide degradation and emerging directions for C. japonicus in both environmental and biotechnological applications. PMID:27263016

  2. Design, construction, operation, and evaluation of solar systems for industrial process-heat applications in the intermediate-temperature range (212/sup 0/F to 550/sup 0/F). Environmental assessment

    Energy Technology Data Exchange (ETDEWEB)

    None

    1982-01-01

    The environmental impacts are assessed for a proposed 50,000 square foot field of single axis tracking, concentrating solar collectors along the Ohio River in southern Ohio. The facility is planned to produce process steam for use in the production of polystyrene. Absorbed solar energy would heat an aliphatic hydrocarbon synthetic heat transfer fluid to a maximum temperature of 500/sup 0/F. The existing environment is briefly described, particularly regarding air quality. The potential environmental impacts of the solar process heat system on the air, water, soil, endangered species and archaeological and historical resources are examined, including risks due to flood and glare and a comparison of alternatives. Also included are a Consent Judgment relating to two coal-fired boilers in violation of EPA regulations, property data of Gulf Synfluid 4CS (a candidate heat transfer fluid), piping and instrumentation diagrams and schematics, site grade and drainage plan, geological survey map, subsurface soil investigation, Ohio endangered species list, Ohio Archaeological Counsel certification list, and a study of heat transfer fluids and their properties. (LEW)

  3. Capsules of Streptococcus pneumoniae and other bacteria: paradigms for polysaccharide biosynthesis and regulation.

    Science.gov (United States)

    Yother, Janet

    2011-01-01

    Capsular polysaccharides and exopolysaccharides play critical roles in bacterial survival strategies, and they can have important medical and industrial applications. An immense variety of sugars and glycosidic linkages leads to an almost unlimited diversity of potential polysaccharide structures. This diversity is reflected in the large number of serologically and chemically distinct polysaccharides that have been identified among both gram-positive and gram-negative bacteria. Despite this diversity, however, the genetic loci and mechanisms responsible for polysaccharide biosynthesis exhibit conserved features and can be classified into a small number of groups. In Streptococcus pneumoniae, capsule synthesis occurs by one of two distinct mechanisms that involve the polymerization of either individual sugars in a processive reaction (synthase dependent) or discrete repeat units in a nonprocessive reaction (Wzy dependent). Characterization of these systems has provided novel insights that are applicable to polymers synthesized by many gram-positive and gram-negative bacteria, as well as eukaryotes.

  4. An extracellular Staphylococcus epidermidis polysaccharide: relation to Polysaccharide Intercellular Adhesin and its implication in phagocytosis

    Directory of Open Access Journals (Sweden)

    Spiliopoulou Anastasia I

    2012-05-01

    Full Text Available Abstract Background The skin commensal and opportunistic pathogen Staphylococcus epidermidis is a leading cause of hospital-acquired and biomaterial-associated infections. The polysaccharide intercellular adhesin (PIA, a homoglycan composed of β-1,6-linked N-acetylglucosamine residues, synthesized by enzymes encoded in icaADBC is a major functional factor in biofilm accumulation, promoting virulence in experimental biomaterial-associated S. epidermidis infection. Extracellular mucous layer extracts of S. epidermidis contain another major polysaccharide, referred to as 20-kDa polysaccharide (20-kDaPS, composed mainly out of glucose, N-acetylglucosamine, and being partially sulfated. 20-kDaPS antiserum prevents adhesion of S. epidermidis on endothelial cells and development of experimental keratitis in rabbits. Here we provide experimental evidence that 20-kDaPS and PIA represent distinct molecules and that 20-kDaPS is implicated in endocytosis of S. epidermidis bacterial cells by human monocyte-derived macrophages. Results Analysis of 75 clinical coagulase-negative staphylococci from blood-cultures and central venous catheter tips indicated that 20-kDaPS is expressed exclusively in S. epidermidis but not in other coagulase-negative staphylococcal species. Tn917-insertion in various locations in icaADBC in mutants M10, M22, M23, and M24 of S. epidermidis 1457 are abolished for PIA synthesis, while 20-kDaPS expression appears unaltered as compared to wild-type strains using specific anti-PIA and anti-20-kDaPS antisera. While periodate oxidation and dispersin B treatments abolish immuno-reactivity and intercellular adhesive properties of PIA, no abrogative activity is exerted towards 20-kDaPS immunochemical reactivity following these treatments. PIA polysaccharide I-containing fractions eluting from Q-Sepharose were devoid of detectable 20-kDaPS using specific ELISA. Preincubation of non-20-kDaPS-producing clinical strain with increasing amounts of

  5. Biochemical And Genetic Modification Of Polysaccharides

    Science.gov (United States)

    Kern, Roger G.; Petersen, Gene R.; Richards, Gil F.

    1993-01-01

    Bacteriophages producing endopolysaccharase-type enzymes used to produce, isolate, and purify high yields of modified polysaccharides from polysaccharides produced by, and incorporated into capsules of, certain bacteria. Bacteriophages used in conversion of native polysaccharide materials into polymers of nearly uniform high molecular weight or, alternatively, into highly pure oligosaccharides. Also used in genetic selection of families of polysaccharides structurally related to native polysaccharide materials, but having altered properties. Resulting new polysaccharides and oligosaccharides prove useful in variety of products, including pharmaceutical chemicals, coating materials, biologically active carbohydrates, and drag-reducing additives for fluids.

  6. Palmitoylation of xanthan polysaccharide for self-assembly microcapsule formation and encapsulation of cells in physiological conditions

    OpenAIRE

    Mendes, Ana Carina; Baran, Erkan Türker; Nunes, Cláudia; Coimbra, Manuel A.; Azevedo, Helena S.; Reis, R. L.

    2011-01-01

    Hydrophobized polysaccharides have emerged as a promising strategy in the biomedical field due to the versatility to design functional structures through the spontaneous self-assembly in cell-friendly conditions. Based on this concept, xanthan, a bacterial extracellular polysaccharide with potential as encapsulating matrix, was conjugated with hydrophobic palmitoyl groups to obtain an amphiphilic system able to form capsules by self-assembly processes. The conjugation of xanthan was performed...

  7. Structural determination of Streptococcus pneumoniae repeat units in serotype 41A and 41F capsular polysaccharides to probe gene functions in the corresponding capsular biosynthetic loci

    DEFF Research Database (Denmark)

    Petersen, Bent O.; Skovsted, Ian C.; Paulsen, Berit Smestad;

    2014-01-01

    (1) by anambitionto help close the remaining gaps in S. pneumoniaecapsular polysaccharide structures, and (2)by the attempt to derive functional annotationsof carbohydrate active enzymes in the biosynthesis of bacterial polysaccharides from the determined structures. Anactivitypresent in 41F but not...... genomic information and computational homology searches. In combination with complementary information, NMR spectroscopy considerably simplifiesthe functional annotation of carbohydrate active enzymes in the biosynthesis of bacterial polysaccharides......We report the repeating unit structures ofthe native capsular polysaccharidesof S. pneumoniaeserotypes 41A and 41F. Structuraldeterminationsyieldedsix carbohydrate units in the doubly branched repeating unit to givethe following structure for serotype 41A:The structure determinations were motivated...

  8. Transcriptional Responses of Bacillus cereus towards Challenges with the Polysaccharide Chitosan : Direct Dating, Culture and Behavior

    NARCIS (Netherlands)

    Mellegard, Hilde; Kovacs, Akos T.; Lindback, Toril; Christensen, Bjorn E.; Kuipers, Oscar P.; Granum, Per E.

    2011-01-01

    The antibacterial activity of the polysaccharide chitosan towards different bacterial species has been extensively documented. The response mechanisms of bacteria exposed to this biopolymer and the exact molecular mechanism of action, however, have hardly been investigated. This paper reports the tr

  9. Radiation processing of polysaccharides

    International Nuclear Information System (INIS)

    Radiation processing is a very convenient tool for imparting desirable effects in polymeric materials and it has been an area of enormous interest in the last few decades. The success of radiation technology for processing of synthetic polymers can be attributed to two reasons namely, their ease of processing in various shapes and sizes, and secondly, most of these polymers undergo crosslinking reaction upon exposure to radiation. In recent years, natural polymers are being looked at with renewed interest because of their unique characteristics, such as inherent biocompatibility, biodegradability and easy availability. Traditionally, the commercial exploitation of natural polymers like carrageenans, alginates or starch etc. has been based, to a large extent, on empirical knowledge. But now, the applications of natural polymers are being sought in knowledge - demanding areas such as pharmacy and biotechnology, which is acting as a locomotive for further scientific research in their structure-function relationship. Selected success stories concerning radiation processed natural polymers and application of their derivatives in the health care products industries and agriculture are reported. This publication will be of interest to individuals at nuclear institutions worldwide that have programmes of R and D and applications in radiation processing technologies. New developments in radiation processing of polymers and other natural raw materials give insight into converting them into useful products for every day life, human health and environmental remediation. The book will also be of interest to other field specialists, readers including managers and decision makers in industry (health care, food and agriculture) helping them to understand the important role of radiation processing technology in polysaccharides

  10. A method for f{sub 0}F{sub 2} monitoring over Spain using the El Arenosillo digisonde current observations

    Energy Technology Data Exchange (ETDEWEB)

    Mikhailov, A. [Institute of Terrestial Magnetism, Ionosphere and Radio Wave Propagation, Russian Academy of Sciences, Troitsk, Moscow Region (Russian Federation); La Morena de, B.A.; Miro, G.; Marin, D. [National Institute of Aerospace Technology, Mazagon, Huelva (Spain)

    1999-08-01

    Ionosphere monitoring implies: observations, prediction and mapping of ionospheric parameter. A case with one available (El Arenosillo) ionosonde is considered. Some statistical methods for f{sub 0}F{sub 2} short-term (1-24 h in advance) prediction are compared. The analysis of multi-dimensional regression for {delta}f{sub 0}F{sub 2} (relative deviation for running median) with A{sub p}, F{sub 10}.{sub 7} and previous {delta}f{sub 0}F{sub 2} observations has shown that inclusion of additional terms with A{sub p} and F{sub 10}.{sub 7} improves the prediction accuracy for lead time more than 15 h. For lead time 1-6 h a linear regression with earlier observed {delta}f{sub 0}F{sub 2} provides the f{sub 0}F{sub 2} forecast with Relative Mean Deviation (RMD) 6-11%. This is acceptable from a practical point of view. A 24-h forecast can be done with RMD 10-11%. Multi-regressional methods provide better prediction accuracy than the usual 10-day running median or quasi-inertial method based on such median. Hourly f{sub 0}F{sub 2} values may be used to calculate the effective index R{sub 12e}ff used as input to the ITU-R monthly median model. This allows the ITU-R model to 'breathe' following hour-to-hour f{sub 0}F{sub 2} variations. Mapping accuracy based on the hourly R{sub 12e}ff index is shown to be 9-11% depending on solar activity level.

  11. Utilization of polysaccharides by radiation processing

    International Nuclear Information System (INIS)

    Radiation treatment has been applied for improvement or pasteurization of agro-resources to recycle the resources and to reduce the pollution of environment. By using the radiation effect for pasteurization, upgrading of cellulosic wastes of oil palm to animal feeds and mushroom has been studied under the bilateral research cooperation between JAERI and MINT (Malaysian Institute for Nuclear Technology Research). The necessary dose for pasteurization of oil palm empty fruit bunch (EFB), which is a main cellulosic by-product of palm oil industry, was determined as 10 kGy. After pasteurization, the EFB substrate was inoculated with Pleurotus sajor-caju and fermented for 1 month. The digestibility and nutritional value of fermented products were evaluated as ruminant feeds and the mushroom can be produced as by-product. For the improvement of resources, radiation effects on polysaccharides such as chitosan, sodium alginate, carrageenan, cellulose, pectin have been investigated to induce the biological activities. These carbohydrates were easily degraded by irradiation and induced various kinds of biological activities. The anti-bacterial activity and elicitor activity of chitosan were induced by irradiation. The induction of phytoalexins was also observed by irradiated pectin but the higher elicitor activity for pisatin was obtained by chitosan than pectin. For the plant growth promotion, alginate derived from brown marine algae, chitosan and ligno-cellulosic extracts show a strong activity. carrageenan derived from red marine algae can promote growth of rice and the highest effect was obtained with kappa carrageenan irradiated at 100 kGy. Furthermore, some radiation degraded polysaccharides suppressed the damage of environmental stress on plants. (author)

  12. Utilization of polysaccharides by radiation processing

    Energy Technology Data Exchange (ETDEWEB)

    Kume, Tamikazu [Japan Atomic Energy Research Inst., Takasaki, Gunma (Japan). Takasaki Radiation Chemistry Research Establishment

    2000-03-01

    Radiation treatment has been applied for improvement or pasteurization of agro-resources to recycle the resources and to reduce the pollution of environment. By using the radiation effect for pasteurization, upgrading of cellulosic wastes of oil palm to animal feeds and mushroom has been studied under the bilateral research cooperation between JAERI and MINT (Malaysian Institute for Nuclear Technology Research). The necessary dose for pasteurization of oil palm empty fruit bunch (EFB), which is a main cellulosic by-product of palm oil industry, was determined as 10 kGy. After pasteurization, the EFB substrate was inoculated with Pleurotus sajor-caju and fermented for 1 month. The digestibility and nutritional value of fermented products were evaluated as ruminant feeds and the mushroom can be produced as by-product. For the improvement of resources, radiation effects on polysaccharides such as chitosan, sodium alginate, carrageenan, cellulose, pectin have been investigated to induce the biological activities. These carbohydrates were easily degraded by irradiation and induced various kinds of biological activities. The anti-bacterial activity and elicitor activity of chitosan were induced by irradiation. The induction of phytoalexins was also observed by irradiated pectin but the higher elicitor activity for pisatin was obtained by chitosan than pectin. For the plant growth promotion, alginate derived from brown marine algae, chitosan and ligno-cellulosic extracts show a strong activity. carrageenan derived from red marine algae can promote growth of rice and the highest effect was obtained with kappa carrageenan irradiated at 100 kGy. Furthermore, some radiation degraded polysaccharides suppressed the damage of environmental stress on plants. (author)

  13. Self-welding evaluation of type 304 and A286 stainless steel in the temperature range 800/sup 0/-1140/sup 0/F in flowing sodium

    Energy Technology Data Exchange (ETDEWEB)

    Chang, J.Y.; Flagella, P.N.; Schrock, S.L.

    1976-01-01

    This paper covers two material combinations, Type 304 SS vs Type 304 SS and Type 304 SS vs A286, tested at temperatures from 800 to 1140/sup 0/F for time periods up to six months in flowing sodium. Contact stresses ranged from 2 to 30 ksi on contact areas for 0.63 to 1.00 in./sup 2/. Tests were performed in either tensile or shear modes on the flat-on-flat samples. Surface morphologies of the sample before and after the test were presented. Self-welding of Type 304 SS was significant at temperatures above 1080/sup 0/F while no self-welding was detected at 800/sup 0/F. Sliding friction coefficient (..mu..) data for a Type 304 SS couple at 800/sup 0/F under compressive stresses from 2000 to 30,000 psi in sodium could be correlated quite accurately by W/sigma = 0.08e/sup 9..mu../, where W is the waviness height in microinches and sigma is the compressive stress in kilo-pound per square inch. One self-weld couple of Type 304 SS/Type 304 SS exposed at 1080/sup 0/F for 3 months was not separated but rather removed intact from the test apparatus and examined in cross-section. Scanning electron micrographs of the contacted area revealed that portions of the original interface were no longer discernible. (auth)

  14. A Prediction Method for△f0F2min of a Single Station From Interplanetary Parameters Based on Statistical Study

    Institute of Scientific and Technical Information of China (English)

    LI Zheng; WEI Fengsi; FENG Xueshang; GUO Jianpeng; XU Xiaojun

    2012-01-01

    Using 86 CME-interplanetary shock events,the correlation between the peak values of (a) the solar wind parameters(Bz,Ey,Pdyn) and the geomagnetic indices(SYM-H,ASY-H,Kp), (b) the coupling functions(Borovsky,Akasofu,Newell) and the geomagnetic indices,(c) the solar wind parameters/coupling functions/geomagnetic indices and the ionospheric parameter(△f0F2min), are investigated.The statistical results show that in group(a),Bz min and SYM-Hmin have the best correlation,that in group(b),the best correlation is between the peak values of Akasofu function (Amin) and SYM-Hmin,and that in group(c),the best correlation is between (pmax and △f0F2min). Based on the statistical results,a method for predicting f0F2 of a single station is attempted to be set up.The input is modified B_(z min) and the outputs are SYM-Hmin and △f0F2min.Then 25 CME-IPS events that caused geomagnetic storms in 1998 and 2009 are used to check the prediction method. The results show that our method can be used to predict SYM-Hmin and △f0F2min

  15. Immunochemical characterization of polysaccharide antigens from six clinical strains of Enterococci

    Directory of Open Access Journals (Sweden)

    Huebner Johannes

    2006-07-01

    Full Text Available Abstract Background Enterococci have become major nosocomial pathogens due to their intrinsic and acquired resistance to a broad spectrum of antibiotics. Their increasing drug resistance prompts us to search for prominent antigens to develop vaccines against enterococci. Given the success of polysaccharide-based vaccines against various bacterial pathogens, we isolated and characterized the immunochemical properties of polysaccharide antigens from five strains of Enterococcus faecalis and one strain of vancomycin-resistant E. faecium. Results We cultured large batches of each strain, isolated sufficient quantities of polysaccharides, analyzed their chemical structures, and compared their antigenic specificity. Three classes of polysaccharides were isolated from each strain, including a polyglucan, a teichoic acid, and a heteroglycan composed of rhamnose, glucose, galactose, mannosamine, and glucosamine. The polyglucans from all six strains are identical and appear to be dextran. Yields of the teichoic acids were generally low. The most abundant polysaccharides are the heteroglycans. The six heteroglycans are structurally different as evidenced by NMR spectroscopy. They also differ in their antigenic specificities as revealed by competitive ELISA. The heteroglycans are not immunogenic by themselves but conjugation to protein carriers significantly enhanced their ability to induce antibodies. Conclusion The six clinical strains of enterococci express abundant, strain-specific cell-surface heteroglycans. These polysaccharides may provide a molecular basis for serological typing of enterococcal strains and antigens for the development of vaccines against multi-drug resistant enterococci.

  16. Variation of the feedback coefficient with R12 and the geographic latitude in 1-h ahead forecast of f0 F2

    OpenAIRE

    Tulunay, Y.; E. Mizrahi; Bilge, A. H.

    2002-01-01

    The «prediction» and «forecast» of the critical frequency of the F 2 layer (f0 F2 ) is an important issue for frequency planning in short wave radio communications. In this context, «prediction» is used for the determination of monthly median values of f0 F2 for each hour, while «forecast» denotes the determination of hourly values. In a previous paper we proposed a «sliding window» technique for prediction combined with «feedback» for forecast (Bilge and Tulunay, 2000). In the present paper ...

  17. D0 Silicon Upgrade: Heat Transfer and Thermal Bowing Calculations of the D0 F-Diskl

    Energy Technology Data Exchange (ETDEWEB)

    Ratzmann, Paul M.; /Fermilab

    1996-08-26

    Shown in Figure 1 is a side view of the D0 F-disk assembly. SVX II chips are mounted to a flex copper/kapton Circuit, which is glued to a beryllium substrate. Figure 1 shows the top and bottom disk assemblies mounted on the cooling channel. However the disks are not mounted directly opposite one another as shown, but alternately rotate through 30{sup o} wedges mounted on either side of the cooling channel. The assumed channel temperature for these calculations is 0 C, as in the cases of the ladder cooling calculations, ref. [1] and [2]. The assumed SVX II chip power is 0.400 W. The finite difference method is used to calculate the temperature profiles of the various components. It is described in Ref. [1]. Each disk is read out using SVX II chips on both sides of the silicon. The silicon is 59.2 mm wide at its widest location. The SVX II chip location opposite the cooling channel has 8 chips mounted on the hybrid. and there are 6 SVX II chips mounted outboard of the cooling channel on the same side as the cooling channel. The SVX II chips mounted on the same side as the cooling channel read out the silicon via a jumper which passes between the beryllium substrate and the cooling channel. Currently there are two substrate materials under consideration for the jumper; kapton/copper and silicon/aluminum. The two materials have different thermal properties. so both will be considered in this note in order to compare their performance in the two different assemblies. The silicon jumper is assumed to be 0.3 mm thick with a thermal conductivity of 0.15 W/mm-K. The kapton/copper flex circuit is assumed to be 0.075 mm in thickness, with 1/2 oz copper traces (a thickness of 0.017 mm copper with 0.4 W/m-K thermal conductivity) along the length. The thermal conductivity of kapton is 0.12E-3 W/mm-K [3]. The F-Disk region is occupied by cables which extend from the barrel ladders. The cables dissipate power [4] and will contribute to warming the gas. The SVX IT chips on both the

  18. Campylobacter jejuni cocultured with epithelial cells reduces surface capsular polysaccharide expression.

    LENUS (Irish Health Repository)

    Corcionivoschi, N

    2012-02-01

    The host cell environment can alter bacterial pathogenicity. We employed a combination of cellular and molecular techniques to study the expression of Campylobacter jejuni polysaccharides cocultured with HCT-8 epithelial cells. After two passages, the amount of membrane-bound high-molecular-weight polysaccharide was considerably reduced. Microarray profiling confirmed significant downregulation of capsular polysaccharide (CPS) locus genes. Experiments using conditioned media showed that sugar depletion occurred only when the bacterial and epithelial cells were cocultured. CPS depletion occurred when C. jejuni organisms were exposed to conditioned media from a different C. jejuni strain but not when exposed to conditioned media from other bacterial species. Proteinase K or heat treatment of conditioned media under coculture conditions abrogated the effect on the sugars, as did formaldehyde fixation and cycloheximide treatment of host cells or chloramphenicol treatment of the bacteria. However, sugar depletion was not affected in flagellar export (fliQ) and quorum-sensing (luxS) gene mutants. Passaged C. jejuni showed reduced invasiveness and increased serum sensitivity in vitro. C. jejuni alters its surface polysaccharides when cocultured with epithelial cells, suggesting the existence of a cross talk mechanism that modulates CPS expression during infection.

  19. Antibiotic resistance of bacterial biofilms

    DEFF Research Database (Denmark)

    Hoiby, N.; Bjarnsholt, T.; Givskov, M.;

    2010-01-01

    A biofilm is a structured consortium of bacteria embedded in a self-produced polymer matrix consisting of polysaccharide, protein and DNA. Bacterial biofilms cause chronic infections because they show increased tolerance to antibiotics and disinfectant chemicals as well as resisting phagocytosis...... and other components of the body's defence system. The persistence of, for example, staphylococcal infections related to foreign bodies is due to biofilm formation. Likewise, chronic Pseudomonas aeruginosa lung infection in cystic fibrosis patients is caused by biofilm-growing mucoid strains....... Characteristically, gradients of nutrients and oxygen exist from the top to the bottom of biofilms and these gradients are associated with decreased bacterial metabolic activity and increased doubling times of the bacterial cells; it is these more or less dormant cells that are responsible for some of the tolerance...

  20. Biodegradable films produced from the bacterial polysaccharide FucoPol.

    Science.gov (United States)

    Ferreira, Ana R V; Torres, Cristiana A V; Freitas, Filomena; Reis, Maria A M; Alves, Vítor D; Coelhoso, Isabel M

    2014-11-01

    FucoPol, an exopolysaccharide produced by Enterobacter A47, grown in bioreactor with glycerol as carbon source, was used with citric acid to obtain biodegradable films by casting. The films were characterized in terms of optical, hygroscopic, mechanical and barrier properties. These films have shown to be transparent, but with a brown tone, imparting small colour changes when applied over coloured surfaces. They were hydrophilic, with high permeability to water vapour (1.01×10(-11)mol/msPa), but presented good barrier properties to oxygen and carbon dioxide (0.7×10(-16)molm/m(2)sPa and 42.7×10(-16)molm/m(2)sPa, respectively). Furthermore, films have shown mechanical properties under tensile tests characteristic of ductile films with high elongation at break, low tension at break and low elastic modulus. Although the obtained results are promising, films properties can be improved, namely by testing alternative plasticizers, crosslinking agents and blends with other biopolymers. Taking into account the observed ductile mechanical properties, good barrier properties to gases when low water content is used and their hydrophilic character, it is foreseen a good potential for FucoPol films to be incorporated as inner layer of a multilayer packaging material. PMID:24769364

  1. Tumor necrosis factor-alpha and acute phase proteins in early pregnant ewes after challenge with peptidoglycan-polysaccharide (PG-PS).

    Science.gov (United States)

    Bacterial infection shortly after breeding interferes with establishment and progression of pregnancy. This is particularly relevant in cases of Gram-positive bacterial infection wherein it can be demonstrated that the injection of peptidoglycan-polysaccharide (PG-PS), a component of Gram-positive ...

  2. Genetic evidence for the involvement of the S-layer protein gene sap and the sporulation genes spo0A, spo0B, and spo0F in Phage AP50c infection of Bacillus anthracis.

    Science.gov (United States)

    Plaut, Roger D; Beaber, John W; Zemansky, Jason; Kaur, Ajinder P; George, Matroner; Biswas, Biswajit; Henry, Matthew; Bishop-Lilly, Kimberly A; Mokashi, Vishwesh; Hannah, Ryan M; Pope, Robert K; Read, Timothy D; Stibitz, Scott; Calendar, Richard; Sozhamannan, Shanmuga

    2014-03-01

    In order to better characterize the Bacillus anthracis typing phage AP50c, we designed a genetic screen to identify its bacterial receptor. Insertions of the transposon mariner or targeted deletions of the structural gene for the S-layer protein Sap and the sporulation genes spo0A, spo0B, and spo0F in B. anthracis Sterne resulted in phage resistance with concomitant defects in phage adsorption and infectivity. Electron microscopy of bacteria incubated with AP50c revealed phage particles associated with the surface of bacilli of the Sterne strain but not with the surfaces of Δsap, Δspo0A, Δspo0B, or Δspo0F mutants. The amount of Sap in the S layer of each of the spo0 mutant strains was substantially reduced compared to that of the parent strain, and incubation of AP50c with purified recombinant Sap led to a substantial reduction in phage activity. Phylogenetic analysis based on whole-genome sequences of B. cereus sensu lato strains revealed several closely related B. cereus and B. thuringiensis strains that carry sap genes with very high similarities to the sap gene of B. anthracis. Complementation of the Δsap mutant in trans with the wild-type B. anthracis sap or the sap gene from either of two different B. cereus strains that are sensitive to AP50c infection restored phage sensitivity, and electron microscopy confirmed attachment of phage particles to the surface of each of the complemented strains. Based on these data, we postulate that Sap is involved in AP50c infectivity, most likely acting as the phage receptor, and that the spo0 genes may regulate synthesis of Sap and/or formation of the S layer.

  3. High field nuclear magnetic resonance application to polysaccharide chemistry

    International Nuclear Information System (INIS)

    Nuclear magnetic resonance has been applied to polysaccharide chemistry using time averaging technique and high fields (100 and 250 MHz). The three methyl signals of methyl cellulose and cellulose triacetate are separated, and the C-6 substituent has been identified. Biosynthesis of bacterial cellulose has been performed using deuterium labelled D-glucose and Acetobacter xylinum. Per-acetylated derivative of bacterial cellulose has been studied by NMR; this study permitted us to determine the quantity of deuterium on each position of the anhydro-glucose unit in the polymer. NMR has also been used to see the anomeric end chain of cellulose and amylose derivatives and to show the fixation of bromine and t-butyl group on the free anomeric end chain of cellulose triacetate. (author)

  4. Sucrose release from polysaccharide gels.

    Science.gov (United States)

    Nishinari, Katsuyoshi; Fang, Yapeng

    2016-05-18

    Sucrose release from polysaccharide gels has been studied extensively because it is expected to be useful in understanding flavour release from solid foods and to find a new processing method which produces more palatable and healthier foods. We provide an overview of the release of sucrose and other sugars from gels of agar and related polysaccharides. The addition of sucrose to agar solutions leads to the increase in transparency of the resulting gels and the decrease in syneresis, which is attributed to the decrease in mesh size in gels. The syneresis occurring in the quiescent condition and fluid release induced by compression is discussed. The relationship between the sugar release and the structural, rheological and thermal properties of gels is also discussed. Finally, the future research direction is proposed.

  5. Structure of the β-l-fucopyranosyl phosphate-containing O-specific polysaccharide of Escherichia coli O84.

    Science.gov (United States)

    Knirel, Yuriy A; Qian, Chengqian; Senchenkova, Sofya N; Guo, Xi; Shashkov, Alexander S; Chizhov, Alexander O; Perepelov, Andrei V; Liu, Bin

    2016-07-01

    Fine structure of the O-polysaccharide chain of the lipopolysaccharide (O-antigen) defines the serospecificity of bacterial cells, which is the basis for O-serotyping of medically and agriculturally important gram-negative bacteria including Escherichia coli. In order to obtain the O-polysaccharide for structural analysis, the lipopolysaccharide was isolated from cells of E. coli O84a by phenol/water extraction and degraded with mild acid. However, the O-polysaccharide was cleaved at a highly acid-labile β-l-fucopyranosyl phosphate (β-l-Fucp-1-P) linkage to give mainly a pentasaccharide that corresponded to the O-polysaccharide repeat. Therefore, the lipopolysaccharide and the pentasaccharide as well as their O-deacylated derivatives were studied using sugar analysis, NMR spectroscopy, and (for oligosaccharides) ESI HR MS, and the O84-polysaccharide structure was established. The O-polysaccharide is distinguished by the presence of β-l-Fucp-1-P and randomly di-O-acetylated 6-deoxy-d-talose, which are found for the first time in natural carbohydrates. The gene cluster for the O84-antigen biosynthesis was analysed and its content was found to be consistent with the O-polysaccharide structure. PMID:27083849

  6. Polysaccharide-Based Micelles for Drug Delivery

    Directory of Open Access Journals (Sweden)

    Nan Zhang

    2013-05-01

    Full Text Available Delivery of hydrophobic molecules and proteins has been an issue due to poor bioavailability following administration. Thus, micelle carrier systems are being investigated to improve drug solubility and stability. Due to problems with toxicity and immunogenicity, natural polysaccharides are being explored as substitutes for synthetic polymers in the development of new micelle systems. By grafting hydrophobic moieties to the polysaccharide backbone, self-assembled micelles can be readily formed in aqueous solution. Many polysaccharides also possess inherent bioactivity that can facilitate mucoadhesion, enhanced targeting of specific tissues, and a reduction in the inflammatory response. Furthermore, the hydrophilic nature of some polysaccharides can be exploited to enhance circulatory stability. This review will highlight the advantages of polysaccharide use in the development of drug delivery systems and will provide an overview of the polysaccharide-based micelles that have been developed to date.

  7. Enzymatic modification of bacterial exopolysaccharides; xanthan lyase as a tool for structural and functional modification of xanthan

    NARCIS (Netherlands)

    Ruijssenaars, H.J.

    2001-01-01

    Bacterial extracellular polysaccharides (EPSs) can be applied, e.g., in foods, as a thickener or stabilizer. The functional properties that make a polysaccharide suitable for such applications are largely determined by the primary structure, i.e., the sugar composition, the linkage types between the

  8. Retention Behaviors of Uronic Acid-containing Polysaccharides and Neutral Polysaccharides in HPGPC

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    The chromatographic behaviors of several uronic acid-containing polysaccharides and neutral polysaccharides were investigated in HPGPC for the first time. The effects of sample concentration and ionic strength of mobile phase on retention time were studied. The mechanism for the effects on Mw determination results of polysaccharides by HPGPC was also discussed.

  9. The Cultivable Surface Microbiota of the Brown Alga Ascophyllum nodosum is Enriched in Macroalgal-Polysaccharide-Degrading Bacteria.

    Science.gov (United States)

    Martin, Marjolaine; Barbeyron, Tristan; Martin, Renee; Portetelle, Daniel; Michel, Gurvan; Vandenbol, Micheline

    2015-01-01

    Bacteria degrading algal polysaccharides are key players in the global carbon cycle and in algal biomass recycling. Yet the water column, which has been studied largely by metagenomic approaches, is poor in such bacteria and their algal-polysaccharide-degrading enzymes. Even more surprisingly, the few published studies on seaweed-associated microbiomes have revealed low abundances of such bacteria and their specific enzymes. However, as macroalgal cell-wall polysaccharides do not accumulate in nature, these bacteria and their unique polysaccharidases must not be that uncommon. We, therefore, looked at the polysaccharide-degrading activity of the cultivable bacterial subpopulation associated with Ascophyllum nodosum. From A. nodosum triplicates, 324 bacteria were isolated and taxonomically identified. Out of these isolates, 78 (~25%) were found to act on at least one tested algal polysaccharide (agar, ι- or κ-carrageenan, or alginate). The isolates "active" on algal-polysaccharides belong to 11 genera: Cellulophaga, Maribacter, Algibacter, and Zobellia in the class Flavobacteriia (41) and Pseudoalteromonas, Vibrio, Cobetia, Shewanella, Colwellia, Marinomonas, and Paraglaceciola in the class Gammaproteobacteria (37). A major part represents likely novel species. Different proportions of bacterial phyla and classes were observed between the isolated cultivable subpopulation and the total microbial community previously identified on other brown algae. Here, Bacteroidetes and Gammaproteobacteria were found to be the most abundant and some phyla (as Planctomycetes and Cyanobacteria) frequently encountered on brown algae weren't identified. At a lower taxonomic level, twelve genera, well-known to be associated with algae (with the exception for Colwellia), were consistently found on all three A. nosodum samples. Even more interesting, 9 of the 11 above mentioned genera containing polysaccharolytic isolates were predominant in this common core. The cultivable fraction of

  10. The cultivable surface microbiota of the brown alga Ascophyllum nodosum is enriched in macroalgal-polysaccharide-degrading bacteria

    Directory of Open Access Journals (Sweden)

    Marjolaine eMartin

    2015-12-01

    Full Text Available Bacteria degrading algal polysaccharides are key players in the global carbon cycle and in algal biomass recycling. Yet the water column, which has been studied largely by metagenomic approaches, is poor in such bacteria and their algal-polysaccharide-degrading enzymes. Even more surprisingly, the few published studies on seaweed-associated microbiomes have revealed low abundances of such bacteria and their specific enzymes. However, as macroalgal cell-wall polysaccharides do not accumulate in nature, these bacteria and their unique polysaccharidases must not be that uncommon. We, therefore, looked at the polysaccharide-degrading activity of the cultivable bacterial subpopulation associated with Ascophyllum nodosum. From A. nodosum triplicates, 324 bacteria were isolated and taxonomically identified. Out of these isolates, 78 (~25% were found to act on at least one tested algal polysaccharide (agar, ι- or κ-carrageenan, or alginate. The isolates active on algal-polysaccharides belong to 11 genera: Cellulophaga, Maribacter, Algibacter, and Zobellia in the class Flavobacteriia (41 and Pseudoalteromonas, Vibrio, Cobetia, Shewanella, Colwellia, Marinomonas, and Paraglaceciola in the class Gammaproteobacteria (37. A major part represents likely novel species. Different proportions of bacterial phyla and classes were observed between the isolated cultivable subpopulation and the total microbial community previously identified on other brown algae. Here, Bacteroidetes and Gammaproteobacteria were found to be the most abundant and some phyla (as Planctomycetes and Cyanobacteria frequently encountered on brown algae weren’t identified. At a lower taxonomic level, twelve genera, well-known to be associated with algae (with the exception for Colwellia, were consistently found on all three A. nosodum samples. Even more interesting, 9 of the 11 above mentioned genera containing polysaccharolytic isolates were predominant in this common core. The

  11. Irradiation of three T-111 clad uranium nitride fuel pins for 8070 hours at 990/sup 0/C (1815/sup 0/F)

    Energy Technology Data Exchange (ETDEWEB)

    Slaby, J.G.; Siegel, B.L.; Gedeon, L.; Galbo, R.J.

    1973-10-01

    The design and successful operation of three tantalum alloy (Ta-8W-2Hf) clad uranium mononitride (UN) fuel pins irradiated for 8070 h at 990/sup 0/C (1815/sup 0/F) is described. Two pin diameters having measured burnups of 0.47 and 0.90 uranium atom percent were tested. No clad failures or swelling was detected; however, postirradiation clad samples tested failed with 1 percent strain. The fuel density decrease was 2 percent, and the fission gas release was less than 0.05 percent. Isotropic fuel swelling, which averaged about 0.5 percent, was less than fuel pin assembly clearances. Thus the clad was not strained. Thermocouples with a modified hot zone operated at average temperatures to 1100/sup 0/C (2012/sup 0/F) without failure. Factors that influence the ability to maintain uniform clad temperature as well as the results of the heat transfer calculations are discussed.

  12. Variation of the feedback coefficient with R12 and the geographic latitude in 1-h ahead forecast of f0 F2

    Directory of Open Access Journals (Sweden)

    Y. Tulunay

    2002-06-01

    Full Text Available The «prediction» and «forecast» of the critical frequency of the F 2 layer (f0 F2 is an important issue for frequency planning in short wave radio communications. In this context, «prediction» is used for the determination of monthly median values of f0 F2 for each hour, while «forecast» denotes the determination of hourly values. In a previous paper we proposed a «sliding window» technique for prediction combined with «feedback» for forecast (Bilge and Tulunay, 2000. In the present paper we obtain the variation of the feedback coefficient with R 12 and geographic latitude.

  13. Sulfated polysaccharides from Loligo vulgaris skin: potential biological activities and partial purification.

    Science.gov (United States)

    Abdelmalek, Baha Eddine; Sila, Assaâd; Krichen, Fatma; Karoud, Wafa; Martinez-Alvarez, Oscar; Ellouz-Chaabouni, Semia; Ayadi, Mohamed Ali; Bougatef, Ali

    2015-01-01

    The characteristics, biological properties, and purification of sulfated polysaccharides extracted from squid (Loligo vulgaris) skin were investigated. Their chemical and physical characteristics were determined using X-ray diffraction and infrared spectroscopic analysis. Sulfated polysaccharides from squid skin (SPSS) contained 85.06% sugar, 2.54% protein, 1.87% ash, 8.07% sulfate, and 1.72% uronic acid. The antioxidant properties of SPSS were investigated based on DPPH radical-scavenging capacity (IC50 = 19.42 mg mL(-1)), hydrogen peroxide-scavenging activity (IC50 = 0.91 mg mL(-1)), and β-carotene bleaching inhibition (IC50 = 2.79 mg mL(-1)) assays. ACE-inhibitory activity of SPSS was also investigated (IC50 = 0.14 mg mL(-1)). Further antimicrobial activity assays indicated that SPSS exhibited marked inhibitory activity against the bacterial and fungal strains tested. Those polysaccharides did not display hemolytic activity towards bovine erythrocytes. Fractionation by DEAE-cellulose column chromatography showed three major absorbance peaks. Results of this study suggest that sulfated polysaccharides from squid skin are attractive sources of polysaccharides and promising candidates for future application as dietary ingredients.

  14. Transport of Streptococcus pneumoniae capsular polysaccharide in MHC Class II tubules.

    Directory of Open Access Journals (Sweden)

    Tom Li Stephen

    2007-03-01

    Full Text Available Bacterial capsular polysaccharides are virulence factors and are considered T cell-independent antigens. However, the capsular polysaccharide Sp1 from Streptococcus pneumoniae serotype 1 has been shown to activate CD4(+ T cells in a major histocompatibility complex (MHC class II-dependent manner. The mechanism of carbohydrate presentation to CD4(+ T cells is unknown. We show in live murine dendritic cells (DCs that Sp1 translocates from lysosomal compartments to the plasma membrane in MHCII-positive tubules. Sp1 cell surface presentation results in reduction of self-peptide presentation without alteration of the MHCII self peptide repertoire. In DM-deficient mice, retrograde transport of Sp1/MHCII complexes resulting in T cell-dependent immune responses to the polysaccharide in vitro and in vivo is significantly reduced. The results demonstrate the capacity of a bacterial capsular polysaccharide antigen to use DC tubules as a vehicle for its transport as an MHCII/saccharide complex to the cell surface for the induction of T cell activation. Furthermore, retrograde transport requires the functional role of DM in self peptide-carbohydrate exchange. These observations open new opportunities for the design of vaccines against microbial encapsulated pathogens.

  15. Thermal studies on natural polysaccharide

    Institute of Scientific and Technical Information of China (English)

    Sunil B Bothara; Sudarshan Singh

    2012-01-01

    Objective: To characterize thermal property of natural gums obtained from the seeds of Diospyros melonoxylon(D. melonoxylon) Roxb, Buchanania lanzan (B. lanzan) spreng and Manilkara zapota (M. zapota) (Linn.) P. Royen syn. Methods: Natural gums were thermally characterized using differential scanning calorimetry (DSC), differential thermal analysis (DTA) and thermo-gravimetric analysis (TGA) under nitrogen atmosphere. Major thermal transitions as well as activation energies of the major decomposition stages were determined. Elemental analysis was performed in order to determine the composition of carbon, hydrogen, nitrogen and sulfur. Results: DSC traces indicated a major intense exothermic transition (around 200℃) followed by weaker exotherm(s). Thermogravimetric analysis showed two phase of weight loss. The first phase has minor weight loss in samples is attributed to the loss of adsorbed and structural water of biopolymers or due to desorption of moisture as hydrogen bound water to the saccharide structure. The second weight loss event may be attributed to the polysaccharide decomposition. The initial decomposition temperature (IDT) was calculated from thermograms obtained of TGA, seed Polysaccharide of D. melonoxylon (IDT 221.21℃), B. lanzan (IPDT 170.4℃) and M. zapota (IPDT 178.6℃) were obtained. According to the integral procedural decomposition temperature (IPDT) values calculated based on the TGA thermograms; D. melonoxylon (IPDT 563.3℃), B. lanzan (IPDT 598.1℃) and M. zapota (IPDT 600.6℃) were obtained respectively. The elemental analysis study shows that the isolated natural Polysaccharides consist of certain percentage of carbon, nitrogen, sulphur and hydrogen in all the gums. Conclusions: The results of the present investigation reveal that the natural gums are thermally stable and these gums can be used as release modifiers in various dosage forms.

  16. Pharmacological Action of Adenophora Polysaccharides

    Institute of Scientific and Technical Information of China (English)

    李泱; 李春红; 唐富天; 李新芳

    2004-01-01

    Adenophora polysaccharides (AP), is an active principle extracted from the root of Adenophorae Potaninii Korsh originated in Gansu Province and isolated with boiling water. AP is isolated and purified from the crude drug by DEAE-cellulose and Sephadex G-200 column, with a white powder and mean molecular weight of 8.3×104 , and [α]D20 of AP is + 68. AP is only composed of glucose judging from the analysis of it with patina chromatography (PC) and gas chromatography-mass spectrometer (GC-MS) methods.

  17. Bioactive polysaccharides and gut microbiome (abstract)

    Science.gov (United States)

    Many polysaccharides have shown the ability to reduce plasma cholesterol or postprandial glycemia. Viscosity in the small intestine seems to be required to slow glucose uptake. Cereal mixed linkage beta-glucans, psyllium, glucomannans, and other polysaccharides also seem to require higher molecula...

  18. Transcriptional responses of Bacillus cereus towards challenges with the polysaccharide chitosan

    OpenAIRE

    Hilde Mellegård; Ákos T Kovács; Toril Lindbäck; Christensen, Bjørn E.; Kuipers, Oscar P.; Granum, Per E.

    2011-01-01

    The antibacterial activity of the polysaccharide chitosan towards different bacterial species has been extensively documented. The response mechanisms of bacteria exposed to this biopolymer and the exact molecular mechanism of action, however, have hardly been investigated. This paper reports the transcriptome profiling using DNA microarrays of the type-strain of Bacillus cereus (ATCC 14579) exposed to subinhibitory concentrations of two water-soluble chitosan preparations with defined chemic...

  19. Bupleurum Polysaccharides Attenuates Lipopolysaccharide-Induced Inflammation via Modulating Toll-Like Receptor 4 Signaling

    OpenAIRE

    Wu, Jian; Zhang, Yun-Yi; Guo, Li; LI Hong; Chen, Dao-Feng

    2013-01-01

    Background Bupleurum polysaccharides (BPs), isolated from Bupleurum smithii var. parvifolium, possesses immunomodulatory activity, particularly on inflammation. Bacterial endotoxin lipopolysaccharide (LPS) triggers innate immune responses through Toll-like receptor 4 (TLR4) on host cell membrane. The present study was performed to evaluate whether the therapeutic efficacy of BPs on suppression of LPS’s pathogenecity could be associated with the modulating of TLR4 signaling pathway. Methodolog...

  20. Recognition and degradation of plant cell wall polysaccharides by two human gut symbionts.

    OpenAIRE

    Martens, Eric C.; Lowe, Elisabeth C.; Herbert Chiang; Nicholas A Pudlo; Meng Wu; McNulty, Nathan P.; D Wade Abbott; Bernard Henrissat; Gilbert, Harry J.; Bolam, David N.; Jeffrey I Gordon

    2011-01-01

    Symbiotic bacteria inhabiting the human gut have evolved under intense pressure to utilize complex carbohydrates, primarily plant cell wall glycans in our diets. These polysaccharides are not digested by human enzymes, but are processed to absorbable short chain fatty acids by gut bacteria. The Bacteroidetes, one of two dominant bacterial phyla in the adult gut, possess broad glycan-degrading abilities. These species use a series of membrane protein complexes, termed Sus-like systems, for cat...

  1. Extracellular Polysaccharides in Microbial Biofilm and Their Influence on the Electrophoretic Properties of Microbial Cells

    OpenAIRE

    Růžička, F.; Horká, M. (Marie); Holá, V.

    2011-01-01

    The surfaces of biofilm-positive microorganisms are usually covered with biofilm-specific extracellular polysaccharide substances that play a key role in a biofilm formation and function [1,2] The presence of this substance on the surface can affect the physicochemical properties of the bacterial cell, including the cell-surface hydrophobicity and surface charge The differences in the surface charges lead to the different isoelectric points and the different electromigration characteristics o...

  2. An exocellular polysaccharide and its interactions with proteins

    NARCIS (Netherlands)

    Tuinier, R.

    1999-01-01

    In the food industry polysaccharides are used as thickening or gelling agents. Polysaccharides are usually extracted from plants. Micro-organisms are also capable of excreting polysaccharides: exocellular polysaccharides (EPSs). In some cases EPSs are produced in-situ in food products, notably in ac

  3. Rheology of interfacial protein-polysaccharide composites

    Science.gov (United States)

    Fischer, P.

    2013-05-01

    The morphology and mechanical properties of protein adsorption layers can significantly be altered by the presence of surfactants, lipids, particles, other proteins, and polysaccharides. In food emulsions, polysaccharides are primarily considered as bulk thickener but can under appropriate environmental conditions stabilize or destabilize the protein adsorption layer and, thus, the entire emulsion system. Despite their ubiquitous usage as stabilization agent, relatively few investigations focus on the interfacial rheology of composite protein/polysaccharide adsorption layers. The manuscript provides a brief review on both main stabilization mechanisms, thermodynamic phase separation and electrostatic interaction and discusses the rheological response in light of the environmental conditions such as ionic strength and pH.

  4. Radiation processing of polysaccharides for agriculture

    International Nuclear Information System (INIS)

    Radiation of polysaccharides generates various types of degraded fragments by random scission. Polysaccharides can be easily degraded both in powder foam and solution. The radiation degraded polysaccharides induce various kinds of biological activities such as anti-microbial activity, promotion of plant growth, suppression of environmental stress, phytoalexins induction and can be applied not only in agriculture but also in medical fields. In this paper, the biological activities induced by radiation of chitosan, alginate, carrageenan, cellulose and pectin are reviewed for the agricultural use. (author)

  5. GEL PERMEATION CHROMATOGRAPHIC ANALYSIS OF LACQUER POLYSACCHARIDE

    Institute of Scientific and Technical Information of China (English)

    QIU Xingping; ZHANG Lina; DU Yumin; QIAN Baogong; LU Zaimin

    1992-01-01

    Ten fractionated samples of Chinese lacquer polysaccharide in aqueous 0.1M NaCl solution were studied by aqueous-phase gel permeation chromatography (GPC). The universal calibration, broad MWD calibration and corrected column dispersion were adopted to the analysis of GPC chromatograms of the polysaccharide. The molecular weights Mw, Mn and polydispersity index Mw/Mn obtained from GPC are in good agreement with the results of light scattering and membrane osmometry. It is verified that the universal calibration concept is applicable to the lacquer polysaccharide having a number of side chains.

  6. Enzymatic production of polysaccharides from gum tragacanth

    DEFF Research Database (Denmark)

    2014-01-01

    Plant polysaccharides, relating to the field of natural probiotic components, can comprise structures similar to human milk oligosaccharides. A method for enzymatic hydrolysis of gum tragacanth from the bush-like legumes of the genus Astragalus, using a combination of pectin hydrolases and a xylo......Plant polysaccharides, relating to the field of natural probiotic components, can comprise structures similar to human milk oligosaccharides. A method for enzymatic hydrolysis of gum tragacanth from the bush-like legumes of the genus Astragalus, using a combination of pectin hydrolases...... and a xylogalacturonan hydrolase, is described. Fractions with different oligo- and/or polysaccharide compositions and structure are separated according to molecular weight....

  7. Evaluation of Phosphorylated Psyllium Seed Polysaccharide as a Release Retardant

    OpenAIRE

    Rao, Monica R. P.; Warrier, Deepa U.; Shivani H. Rao

    2015-01-01

    The aim of the present study was to modify psyllium seed polysaccharide and evaluate the modified polysaccharide as release retardant in tablets employing ciprofloxacin hydrochloride as model drug. Studies on polysaccharide from psyllium husk has been reported but no work has been reported on characterization and modification of the polysaccharide present in the psyllium (Plantago ovata) seed and the use of the modified polysaccharide as a release retardant in tablets. In this study, the seed...

  8. Pharmacological Action of Adenophora Polysaccharides

    Institute of Scientific and Technical Information of China (English)

    李泱; 李春红; 唐富天; 李新芳

    2004-01-01

    @@ Adenophora polysaccharides (AP), is an active principle extracted from the root of Adenophorae Potaninii Korsh originated in Gansu Province and isolated with boiling water(1). AP is isolated and purified from the crude drug by DEAE-cellulose and Sephadex G-200 column, with a white powder and mean molecular weight of 8.3 × 104 , and [α]D20of AP is + 68(1). AP is only composed of glucose judging from the analysis of it with patina chromatography (PC) and gas chromatography-mass spectrometer (GC-MS) methods.The methylation analysis showed that AP is composed of (1→6) linked glucose residues. The measure of nuclear magnetic resonance imaging (NMR) 1H NMR and 14C NMR techniques further proved that AP is α(l→6) linked by Dglucose. The structure of AP is as follows: -[→6]α-D-Glu(1-)n→ (2).

  9. Measurement of Inclusive $\\rho^{0}, f_{0}(980), f_{2}(1270), K^{*0}_{2}(1430)$ and $f'_{2}(1525)$ Production in $Z^0$ Decays

    CERN Document Server

    Abreu, P; Adye, T; Adzic, P; Ajinenko, I; Albrecht, Z; Alderweireld, T; Alekseev, G D; Alemany, R; Allmendinger, T; Allport, P P; Almehed, S; Amaldi, Ugo; Amato, S; Anassontzis, E G; Andersson, P; Andreazza, A; Andringa, S; Antilogus, P; Apel, W D; Arnoud, Y; Åsman, B; Augustin, J E; Augustinus, A; Baillon, Paul; Bambade, P; Barão, F; Barbiellini, Guido; Barbier, R; Bardin, Dimitri Yuri; Barker, G; Baroncelli, A; Battaglia, Marco; Baubillier, M; Becks, K H; Begalli, M; Beillière, P; Belokopytov, Yu A; Benvenuti, Alberto C; Bérat, C; Berggren, M; Bertini, D; Bertrand, D; Besançon, M; Bianchi, F; Bigi, M; Bilenky, S M; Bizouard, M A; Bloch, D; Blom, H M; Bonesini, M; Bonivento, W; Boonekamp, M; Booth, P S L; Borgland, A W; Borisov, G; Bosio, C; Botner, O; Boudinov, E; Bouquet, B; Bourdarios, C; Bowcock, T J V; Boyko, I; Bozovic, I; Bozzo, M; Branchini, P; Brenke, T; Brenner, R A; Brückman, P; Brunet, J M; Bugge, L; Buran, T; Burgsmüller, T; Buschmann, P; Cabrera, S; Caccia, M; Calvi, M; Camporesi, T; Canale, V; Carena, F; Carroll, L; Caso, Carlo; Castillo-Gimenez, M V; Cattai, A; Cavallo, F R; Chabaud, V; Charpentier, P; Chaussard, L; Checchia, P; Chelkov, G A; Chierici, R; Chliapnikov, P V; Chochula, P; Chorowicz, V; Chudoba, J; Cieslik, K; Collins, P; Contri, R; Cortina, E; Cosme, G; Cossutti, F; Cowell, J H; Crawley, H B; Crennell, D J; Crépé, S; Crosetti, G; Cuevas-Maestro, J; Czellar, S; Damgaard, G; Davenport, Martyn; Da Silva, W; Deghorain, A; Della Ricca, G; Delpierre, P A; Demaria, N; De Angelis, A; de Boer, Wim; De Brabandere, S; De Clercq, C; De Lotto, B; De Min, A; De Paula, L S; Dijkstra, H; Di Ciaccio, Lucia; Dolbeau, J; Doroba, K; Dracos, M; Drees, J; Dris, M; Duperrin, A; Durand, J D; Eigen, G; Ekelöf, T J C; Ekspong, Gösta; Ellert, M; Elsing, M; Engel, J P; Erzen, B; Espirito-Santo, M C; Falk, E; Fanourakis, G K; Fassouliotis, D; Fayot, J; Feindt, Michael; Ferrari, P; Ferrer, A; Ferrer-Ribas, E; Fichet, S; Firestone, A; Flagmeyer, U; Föth, H; Fokitis, E; Fontanelli, F; Franek, B J; Frodesen, A G; Fulda-Quenzer, F; Fuster, J A; Galloni, A; Gamba, D; Gamblin, S; Gandelman, M; García, C; Gaspar, C; Gaspar, M; Gasparini, U; Gavillet, P; Gazis, E N; Gelé, D; Gerdyukov, L N; Ghodbane, N; Gil, I; Glege, F; Gokieli, R; Golob, B; Gómez-Ceballos, G; Gonçalves, P; González-Caballero, I; Gopal, Gian P; Gorn, L; Górski, M; Guz, Yu; Gracco, Valerio; Grahl, J; Graziani, E; Green, C; Grimm, H J; Gris, P; Grosdidier, G; Grzelak, K; Günther, M; Guy, J; Hahn, F; Hahn, S; Haider, S; Hallgren, A; Hamacher, K; Hansen, J; Harris, F J; Hedberg, V; Heising, S; Hernández, J J; Herquet, P; Herr, H; Hessing, T L; Heuser, J M; Higón, E; Holmgren, S O; Holt, P J; Hoorelbeke, S; Houlden, M A; Hrubec, Josef; Huet, K; Hughes, G J; Hultqvist, K; Jackson, J N; Jacobsson, R; Jalocha, P; Janik, R; Jarlskog, C; Jarlskog, G; Jarry, P; Jean-Marie, B; Johansson, E K; Jönsson, P E; Joram, C; Juillot, P; Kapusta, F; Karafasoulis, K; Katsanevas, S; Katsoufis, E C; Keränen, R; Kersevan, Borut P; Khomenko, B A; Khovanskii, N N; Kiiskinen, A P; King, B J; Kinvig, A; Kjaer, N J; Klapp, O; Klein, H; Kluit, P M; Kokkinias, P; Koratzinos, M; Kostyukhin, V; Kourkoumelis, C; Kuznetsov, O; Krammer, Manfred; Kriznic, E; Krstic, J; Krumshtein, Z; Kubinec, P; Kurowska, J; Kurvinen, K L; Lamsa, J; Lane, D W; Langefeld, P; Lapin, V; Laugier, J P; Lauhakangas, R; Leder, Gerhard; Ledroit, F; Lefébure, V; Leinonen, L; Leisos, A; Leitner, R; Lenzen, Georg; Lepeltier, V; Lesiak, T; Lethuillier, M; Libby, J; Liko, D; Lipniacka, A; Lippi, I; Lörstad, B; Loken, J G; Lopes, J H; López, J M; López-Fernandez, R; Loukas, D; Lutz, P; Lyons, L; MacNaughton, J N; Mahon, J R; Maio, A; Malek, A; Malmgren, T G M; Malychev, V; Mandl, F; Marco, J; Marco, R P; Maréchal, B; Margoni, M; Marin, J C; Mariotti, C; Markou, A; Martínez-Rivero, C; Martínez-Vidal, F; Martí i García, S; Mastroyiannopoulos, N; Matorras, F; Matteuzzi, C; Matthiae, Giorgio; Masik, J; Mazzucato, F; Mazzucato, M; McCubbin, M L; McKay, R; McNulty, R; McPherson, G; Meroni, C; Meyer, W T; Myagkov, A; Migliore, E; Mirabito, L; Mitaroff, Winfried A; Mjörnmark, U; Moa, T; Moch, M; Møller, R; Mönig, K; Monge, M R; Moreau, X; Morettini, P; Morton, G A; Müller, U; Münich, K; Mulders, M; Mulet-Marquis, C; Muresan, R; Murray, W J; Muryn, B; Myatt, Gerald; Myklebust, T; Naraghi, F; Navarria, Francesco Luigi; Navas, S; Nawrocki, K; Negri, P; Neufeld, N; Neumeister, N; Nicolaidou, R; Nielsen, B S; Nikolenko, M; Nomokonov, V P; Normand, Ainsley; Nygren, A; Obraztsov, V F; Olshevskii, A G; Onofre, A; Orava, Risto; Orazi, G; Österberg, K; Ouraou, A; Paganoni, M; Paiano, S; Pain, R; Paiva, R; Palacios, J; Palka, H; Papadopoulou, T D; Papageorgiou, K; Pape, L; Parkes, C; Parodi, F; Parzefall, U; Passeri, A; Passon, O; Pegoraro, M; Peralta, L; Pernicka, Manfred; Perrotta, A; Petridou, C; Petrolini, A; Phillips, H T; Pierre, F; Pimenta, M; Piotto, E; Podobnik, T; Pol, M E; Polok, G; Poropat, P; Pozdnyakov, V; Privitera, P; Pukhaeva, N; Pullia, Antonio; Radojicic, D; Ragazzi, S; Rahmani, H; Rakoczy, D; Ratoff, P N; Read, A L; Rebecchi, P; Redaelli, N G; Regler, Meinhard; Reid, D; Reinhardt, R; Renton, P B; Resvanis, L K; Richard, F; Rídky, J; Rinaudo, G; Røhne, O M; Romero, A; Ronchese, P; Rosenberg, E I; Rosinsky, P; Roudeau, Patrick; Rovelli, T; Royon, C; Ruhlmann-Kleider, V; Ruiz, A; Saarikko, H; Sacquin, Yu; Sadovskii, A; Sajot, G; Salt, J; Sampsonidis, D; Sannino, M; Schneider, H; Schwemling, P; Schwickerath, U; Schyns, M A E; Scuri, F; Seager, P; Sedykh, Yu; Segar, A M; Sekulin, R L; Shellard, R C; Sheridan, A; Siebel, M; Simard, L C; Simonetto, F; Sissakian, A N; Smadja, G; Smirnova, O G; Smith, G R; Sokolov, A; Sopczak, André; Sosnowski, R; Spassoff, Tz; Spiriti, E; Sponholz, P; Squarcia, S; Stampfer, D; Stanescu, C; Stanic, S; Stevenson, K; Stocchi, A; Strauss, J; Strub, R; Stugu, B; Szczekowski, M; Szeptycka, M; Tabarelli de Fatis, T; Chikilev, O G; Tegenfeldt, F; Terranova, F; Thomas, J; Timmermans, J; Tinti, N; Tkatchev, L G; Todorova, S; Tomaradze, A G; Tomé, B; Tonazzo, A; Tortora, L; Tranströmer, G; Treille, D; Tristram, G; Trochimczuk, M; Troncon, C; Tsirou, A L; Turluer, M L; Tyapkin, I A; Tzamarias, S; Überschär, B; Ullaland, O; Uvarov, V; Valenti, G; Vallazza, E; van Apeldoorn, G W; van Dam, P; Van Doninck, W K; Van Eldik, J; Van Lysebetten, A; Van Vulpen, I B; Vassilopoulos, N; Vegni, G; Ventura, L; Venus, W A; Verbeure, F; Verlato, M; Vertogradov, L S; Verzi, V; Vilanova, D; Vitale, L; Vlasov, E; Vodopyanov, A S; Vollmer, C F; Voulgaris, G; Vrba, V; Wahlen, H; Walck, C; Weiser, C; Wicke, D; Wickens, J H; Wilkinson, G R; Winter, M; Witek, M; Wolf, G; Yi, J; Yushchenko, O P; Zalewska-Bak, A; Zalewski, Piotr; Zavrtanik, D; Zevgolatakos, E; Zimin, N I; Zucchelli, G C; Zumerle, G

    1999-01-01

    DELPHI results are presented on the inclusive production of the neutral mesons$\\rho^0$, $f_0(980)$, $f_2(1270)$, K$^{*0}_2(1430)$ and $f^{'}_2(1525)$ in hadronic Z$^0$ decays. They are based on about 2 million multihadronic events collected in 1994 and 1995, using the particle identification capabilities of the DELPHI Ring Imaging Cherenkov detectors and measured ionization losses in the Time Projection Chamber. The total production rates per hadronic Z$^0$ decay have been determined to be: $1.19 \\pm 0.10$ for $\\rho^0$; $0.164 \\pm 0.021$ for $f_0(980)$;$0.214 \\pm 0.038$ for $f_2(1270)$; 0:073 \\pm 0:023 for $K^{*0}_2 (1430)$; and 0:012 \\pm 0:006 for $f_{2}$(1525). The total production rates for all mesons and differential cross-sections for the $\\rho^{0}$, $f_{0}$(980) and $f_{2}$(1270) are compared with the results of other LEP experiments and with models.

  10. Extraction Optimization of Polysaccharides from Pitaya Stems

    Institute of Scientific and Technical Information of China (English)

    HE Cong-fen; LI Peng; ZHAO Hua; SONG Li-ya; ZHU Jun; DONG Yin-mao

    2011-01-01

    [Objective] The aim was to describe the extraction of polysaccharides from pitaya stems.[Method] The hot water,enzyme-assisted and microwave-assisted methods were used,with the microwave-assisted extraction being deemed optimal by general evaluation.[Result] The main factors affecting the yield of polysaccharides in the microwave-assisted extraction,by order of magnitude,were as follows:timemicrowave powertemperature;additionally,optimal conditions included a 10 min extraction time,an 80 ℃ extraction temperature and a microwave setting of 200 W.Using these optimal conditions,the yield of PSPS(Polysaccharides from Pitaya Stems) was 1.42%.After purification,the yield of PSPS was 0.74%.[Conclusion] The PSPS was analyzed by IR,MALDI-TOF-MS and an element analysis technique.It was shown to be a polysaccharide mixture,and the molecular weight was between 3 900 and 4 300 Da.

  11. Seaweed Polysaccharides and Derived Oligosaccharides Stimulate Defense Responses and Protection Against Pathogens in Plants

    Directory of Open Access Journals (Sweden)

    Alejandra Moenne

    2011-11-01

    Full Text Available Plants interact with the environment by sensing “non-self” molecules called elicitors derived from pathogens or other sources. These molecules bind to specific receptors located in the plasma membrane and trigger defense responses leading to protection against pathogens. In particular, it has been shown that cell wall and storage polysaccharides from green, brown and red seaweeds (marine macroalgae corresponding to ulvans, alginates, fucans, laminarin and carrageenans can trigger defense responses in plants enhancing protection against pathogens. In addition, oligosaccharides obtained by depolymerization of seaweed polysaccharides also induce protection against viral, fungal and bacterial infections in plants. In particular, most seaweed polysaccharides and derived oligosaccharides trigger an initial oxidative burst at local level and the activation of salicylic (SA, jasmonic acid (JA and/or ethylene signaling pathways at systemic level. The activation of these signaling pathways leads to an increased expression of genes encoding: (i Pathogenesis-Related (PR proteins with antifungal and antibacterial activities; (ii defense enzymes such as pheylalanine ammonia lyase (PAL and lipoxygenase (LOX which determine accumulation of phenylpropanoid compounds (PPCs and oxylipins with antiviral, antifugal and antibacterial activities and iii enzymes involved in synthesis of terpenes, terpenoids and/or alkaloids having antimicrobial activities. Thus, seaweed polysaccharides and their derived oligosaccharides induced the accumulation of proteins and compounds with antimicrobial activities that determine, at least in part, the enhanced protection against pathogens in plants.

  12. Changes in the F0F1-ATPase activity of irradiated Lactobacillus acidophilus in the presence of ceftazidime at low pH

    International Nuclear Information System (INIS)

    The aim of this study was the investigation of the effects of low intensity electromagnetic irradiation (EMI) at the frequencies of 51.8 and 53 GHz and of antibiotic ceftazidime on the N,N'-dicyclohexylcarbodiimide (DCCD) inhibited ATPase activity of membrane vesicles of lactic acid bacteria Lactobacillus acidophilus grown at low pH (pH 4.0 or 6.5) and assayed at the same pH. It was shown that both frequencies EMI stimulated ATPase activity of L. acidophilus grown at pH 4.0, but EMI combined with ceftazidime and DCCD decreased ATPase activity at pH 4.0 and pH 6.5. It was suggested that the F0F1-ATPase might be a target for EMI even at low pH

  13. Bacterial Vaginosis

    Science.gov (United States)

    ... 586. Related Content STDs during Pregnancy Fact Sheet Pregnancy and HIV, Viral Hepatitis, and STD Prevention Pelvic Inflammatory Disease ( ... Bacterial Vaginosis (BV) Chlamydia Gonorrhea Genital Herpes Hepatitis HIV/AIDS & STDs Human Papillomavirus ... STDs See Also Pregnancy Reproductive ...

  14. Bacterial Meningitis

    Science.gov (United States)

    ... Schedules Preteen & Teen Vaccines Meningococcal Disease Sepsis Bacterial Meningitis Recommend on Facebook Tweet Share Compartir On this ... serious disease. Laboratory Methods for the Diagnosis of Meningitis This manual summarizes laboratory methods used to isolate, ...

  15. Viscoelastic properties of levan polysaccharides

    Science.gov (United States)

    Noll, Kenneth; Rende, Deniz; Ozisik, Rahmi; Toksoy-Oner, Ebru

    2014-03-01

    Levan is a naturally occurring polysaccharide that is composed of β-D-fructofuranose units with β(2-6) linkages between fructose rings. It is synthesized by the action of a secreted levansucrase (EC 2.4.1.10) that converts sucrose into the levan externally (exopolysaccharide). Levan is a homopolysaccharide that is non-toxic, water soluble,, and has anti-tumor activity and low immunological response. Therefore, levan presents great potential to be used as a novel functional biopolymer in foods, feeds, cosmetics, pharmaceutical and chemical industries. Despite these favorable properties, levan has a moderately low mechanical properties and poor film forming capability. In the current study, the agglomeration behavior of levan in water and in saline solutions was investigated at 298 and 310 K by dynamic light scattering and transmission electron microscopy (TEM). The viscoelastic properties of neat and oxidized levan films were studied via nanoindentation experiments in the quasi-static and dynamic modes The material is partially based upon work supported by NSF under Grant Nos. 1200270 and 1003574, and TUBITAK 111M232.

  16. Structure and molecular characterization of Streptococcus pneumoniae capsular polysaccharide 10F by carbohydrate engineering in Streptococcus oralis.

    Science.gov (United States)

    Yang, Jinghua; Shelat, Nirav Y; Bush, C Allen; Cisar, John O

    2010-07-30

    Although closely related at the molecular level, the capsular polysaccharide (CPS) of serotype 10F Streptococcus pneumoniae and coaggregation receptor polysaccharide (RPS) of Streptococcus oralis C104 have distinct ecological roles. CPS prevents phagocytosis of pathogenic S. pneumoniae, whereas RPS of commensal S. oralis functions as a receptor for lectin-like adhesins on other members of the dental plaque biofilm community. Results from high resolution NMR identified the recognition region of S. oralis RPS (i.e. Galfbeta1-6GalNAcbeta1-3Galalpha) in the hexasaccharide repeat of S. pneumoniae CPS10F. The failure of this polysaccharide to support fimbriae-mediated adhesion of Actinomyces naeslundii was explained by the position of Galf, which occurred as a branch in CPS10F rather than within the linear polysaccharide chain, as in RPS. Carbohydrate engineering of S. oralis RPS with wzy from S. pneumoniae attributed formation of the Galf branch in CPS10F to the linkage of adjacent repeating units through sub terminal GalNAc in Galfbeta1-6GalNAcbeta1-3Galalpha rather than through terminal Galf, as in RPS. A gene (wcrD) from serotype 10A S. pneumoniae was then used to engineer a linear surface polysaccharide in S. oralis that was identical to RPS except for the presence of a beta1-3 linkage between Galf and GalNAcbeta1-3Galalpha. This polysaccharide also failed to support adhesion of A. naeslundii, thereby establishing the essential role of beta1-6-linked Galf in recognition of adjacent GalNAcbeta1-3Galalpha in wild-type RPS. These findings, which illustrate a molecular approach for relating bacterial polysaccharide structure to function, provide insight into the possible evolution of S. oralis RPS from S. pneumoniae CPS. PMID:20507989

  17. A Direct Sulfation Process of a Marine Polysaccharide in Ionic Liquid.

    Science.gov (United States)

    Chopin, Nathalie; Sinquin, Corinne; Ratiskol, Jacqueline; Zykwinska, Agata; Weiss, Pierre; Cérantola, Stéphane; Le Bideau, Jean; Colliec-Jouault, Sylvia

    2015-01-01

    GY785 is an exopolysaccharide produced by a mesophilic bacterial strain Alteromonas infernus discovered in the deep-sea hydrothermal vents. GY785 highly sulfated derivative (GY785 DRS) was previously demonstrated to be a promising molecule driving the efficient mesenchymal stem cell chondrogenesis for cartilage repair. This glycosaminoglycan- (GAG-) like compound was modified in a classical solvent (N,N'-dimethylformamide). However, the use of classical solvents limits the polysaccharide solubility and causes the backbone degradation. In the present study, a one-step efficient sulfation process devoid of side effects (e.g., polysaccharide depolymerization and/or degradation) was developed to produce GAG-like derivatives. The sulfation of GY785 derivative (GY785 DR) was carried out using ionic liquid as a reaction medium. The successful sulfation of this anionic and highly branched heteropolysaccharide performed in ionic liquid would facilitate the production of new molecules of high specificity for biological targets such as tissue engineering or regenerative medicine.

  18. CarbBuilder: Software for building molecular models of complex oligo- and polysaccharide structures.

    Science.gov (United States)

    Kuttel, Michelle M; Ståhle, Jonas; Widmalm, Göran

    2016-08-15

    CarbBuilder is a portable software tool for producing three-dimensional molecular models of carbohydrates from the simple text specification of a primary structure. CarbBuilder can generate a wide variety of carbohydrate structures, ranging from monosaccharides to large, branched polysaccharides. Version 2.0 of the software, described in this article, supports monosaccharides of both mammalian and bacterial origin and a range of substituents for derivatization of individual sugar residues. This improved version has a sophisticated building algorithm to explore the range of possible conformations for a specified carbohydrate molecule. Illustrative examples of models of complex polysaccharides produced by CarbBuilder demonstrate the capabilities of the software. CarbBuilder is freely available under the Artistic License 2.0 from https://people.cs.uct.ac.za/~mkuttel/Downloads.html. © 2016 Wiley Periodicals, Inc. PMID:27317625

  19. Polysaccharides and infrared spectra of galactic sources

    International Nuclear Information System (INIS)

    It is shown that observations that are available for a number of astronomical objects over the infrared waveband 2 to 30 μm are reconcilable with the transmittance properties of polysaccharides, and it is considered reasonable to infer the detection of interstellar polysaccharides. The identification of highly complex macromolecules, such as cellulose, which are presumably formed by an abiogenic processing of interstellar formaldehyde, could have a profound bearing on interstellar chemistry, including the evolution of prebiotic molecules. A discussion is presented on the production of organic molecules in the interstellar medium, with special reference to formaldehyde and its polymers; the polysaccharides have structures built up from H2CO units and are probably the most stable polymers formed. Cellulose and starch are particularly stable, because each (H2C0)6 unit formed is able to form part of a very stable ring, with the polysaccharide becoming a chain of hexagonal ring structures. Cellulose can maintain its structure in a vacuum or a low density inert atmosphere probably up to a temperature around 625 to 900 K. Interstellar solid material is strongly absorbing in two infrared bands, centred at 3 and 10 μm, and it has been usual to attribute these absorptions to crystals of water-ice or magnesium silicate, but this presents certain difficulties, and it seems worthwhile to consider whether the infrared properties of interstellar dust might not be attributed to polysaccharides. (U.K.)

  20. Recognition and degradation of plant cell wall polysaccharides by two human gut symbionts.

    Directory of Open Access Journals (Sweden)

    Eric C Martens

    2011-12-01

    Full Text Available Symbiotic bacteria inhabiting the human gut have evolved under intense pressure to utilize complex carbohydrates, primarily plant cell wall glycans in our diets. These polysaccharides are not digested by human enzymes, but are processed to absorbable short chain fatty acids by gut bacteria. The Bacteroidetes, one of two dominant bacterial phyla in the adult gut, possess broad glycan-degrading abilities. These species use a series of membrane protein complexes, termed Sus-like systems, for catabolism of many complex carbohydrates. However, the role of these systems in degrading the chemically diverse repertoire of plant cell wall glycans remains unknown. Here we show that two closely related human gut Bacteroides, B. thetaiotaomicron and B. ovatus, are capable of utilizing nearly all of the major plant and host glycans, including rhamnogalacturonan II, a highly complex polymer thought to be recalcitrant to microbial degradation. Transcriptional profiling and gene inactivation experiments revealed the identity and specificity of the polysaccharide utilization loci (PULs that encode individual Sus-like systems that target various plant polysaccharides. Comparative genomic analysis indicated that B. ovatus possesses several unique PULs that enable degradation of hemicellulosic polysaccharides, a phenotype absent from B. thetaiotaomicron. In contrast, the B. thetaiotaomicron genome has been shaped by increased numbers of PULs involved in metabolism of host mucin O-glycans, a phenotype that is undetectable in B. ovatus. Binding studies of the purified sensor domains of PUL-associated hybrid two-component systems in conjunction with transcriptional analyses demonstrate that complex oligosaccharides provide the regulatory cues that induce PUL activation and that each PUL is highly specific for a defined cell wall polymer. These results provide a view of how these species have diverged into different carbohydrate niches by evolving genes that target

  1. Immunomodulatory effects of a polysaccharide from Tamarindus indica.

    Science.gov (United States)

    Sreelekha, T T; Vijayakumar, T; Ankanthil, R; Vijayan, K K; Nair, M K

    1993-04-01

    A polysaccharide isolated and purified from Tamarindus indica shows immunomodulatory activities such as phagocytic enhancement, leukocyte migration inhibition and inhibition of cell proliferation. These properties suggest that this polysaccharide from T. indica may have some biological applications.

  2. Immobilized phosphorylase for synthesis of polysaccharides from glucose

    Science.gov (United States)

    Marshall, D. L.

    1972-01-01

    Continuous processes for enzymatic production of carbohydrates from glucose are discussed. Key reactant in process is identified as phosphorylase which catalyzes reversible formation or degradation of polysaccharide. Chemical compounds and reactions to synthesize polysaccharides are analyzed.

  3. Synthesis and interfacial behavior of polystyrene-polysaccharide diblock copolymers

    NARCIS (Netherlands)

    Bosker, W.T.E.; Ágoston, K.; Cohen Stuart, M.A.; Norde, W.; Timmermans, J.W.; Slaghek, T.M.

    2003-01-01

    Linear block copolymers of polystyrene and polysaccharide were synthesized using a block synthesis method with amino-terminated polystyrene and sodium cyanoborohydride as reducing agent. Different types of polysaccharides, dextrans, and maltodextrins with various molecular weights were used. IR spec

  4. Ice nucleation activity of polysaccharides

    Science.gov (United States)

    Bichler, Magdalena; Felgitsch, Laura; Haeusler, Thomas; Seidl-Seiboth, Verena; Grothe, Hinrich

    2015-04-01

    Heterogeneous ice nucleation is an important process in the atmosphere. It shows direct impact on our climate by triggering ice cloud formation and therefore it has much influence on the radiation balance of our planet (Lohmann et al. 2002; Mishchenko et al. 1996). The process itself is not completely understood so far and many questions remain open. Different substances have been found to exhibit ice nucleation activity (INA). Due to their vast differences in chemistry and morphology it is difficult to predict what substance will make good ice nuclei and which will not. Hence simple model substances must be found and be tested regarding INA. Our work aims at gaining to a deeper understanding of heterogeneous ice nucleation. We intend to find some reference standards with defined chemistry, which may explain the mechanisms of heterogeneous ice nucleation. A particular focus lies on biological carbohydrates in regards to their INA. Biological carbohydrates are widely distributed in all kingdoms of life. Mostly they are specific for certain organisms and have well defined purposes, e.g. structural polysaccharides like chitin (in fungi and insects) and pectin (in plants), which has also water-binding properties. Since they are widely distributed throughout our biosphere and mostly safe to use for nutrition purposes, they are well studied and easily accessible, rendering them ideal candidates as proxies. In our experiments we examined various carbohydrates, like the already mentioned chitin and pectin, as well as their chemical modifications. Lohmann U.; A Glaciation Indirect Aerosol Effect Caused by Soot Aerosols; J. Geoph. Res.; Vol. 24 No.4; pp 11-1 - 11-4; 2002 Mishchenko M.I., Rossow W.B., Macke A., Lacis A. A.; Sensitivity of Cirrus Cloud Albedo, Bidirectional Reflectance and Optical Thickness Retrieval Accuracy to Ice Particle Shape, J. Geoph. Res.; Vol. 101, No D12; pp. 16,973 - 16,985; 1996

  5. Bacterial carbonatogenesis

    International Nuclear Information System (INIS)

    Several series of experiments in the laboratory as well as in natural conditions teach that the production of carbonate particles by heterotrophic bacteria follows different ways. The 'passive' carbonatogenesis is generated by modifications of the medium that lead to the accumulation of carbonate and bicarbonate ions and to the precipitation of solid particles. The 'active' carbonatogenesis is independent of the metabolic pathways. The carbonate particles are produced by ionic exchanges through the cell membrane following still poorly known mechanisms. Carbonatogenesis appears to be the response of heterotrophic bacterial communities to an enrichment of the milieu in organic matter. The active carbonatogenesis seems to start first. It is followed by the passive one which induces the growth of initially produced particles. The yield of heterotrophic bacterial carbonatogenesis and the amounts of solid carbonates production by bacteria are potentially very high as compared to autotrophic or chemical sedimentation from marine, paralic or continental waters. Furthermore, the bacterial processes are environmentally very ubiquitous; they just require organic matter enrichment. Thus, apart from purely evaporite and autotrophic ones, all Ca and/or Mg carbonates must be considered as from heterotrophic bacterial origin. By the way, the carbon of carbonates comes from primary organic matter. Such considerations ask questions about some interpretations from isotopic data on carbonates. Finally, bacterial heterotrophic carbonatogenesis appears as a fundamental phase in the relationships between atmosphere and lithosphere and in the geo-biological evolution of Earth. (author)

  6. Influence of polysaccharides on wine protein aggregation.

    Science.gov (United States)

    Jaeckels, Nadine; Meier, Miriam; Dietrich, Helmut; Will, Frank; Decker, Heinz; Fronk, Petra

    2016-06-01

    Polysaccharides are the major high-molecular weight components of wines. In contrast, proteins occur only in small amounts in wine, but contribute to haze formation. The detailed mechanism of aggregation of these proteins, especially in combination with other wine components, remains unclear. This study demonstrates the different aggregation behavior between a buffer and a model wine system by dynamic light scattering. Arabinogalactan-protein, for example, shows an increased aggregation in the model wine system, while in the buffer system a reducing effect is observed. Thus, we could show the importance to examine the behavior of wine additives under conditions close to reality, instead of simpler buffer systems. Additional experiments on melting points of wine proteins reveal that only some isoforms of thaumatin-like proteins and chitinases are involved in haze formation. We can confirm interactions between polysaccharides and proteins, but none of these polysaccharides is able to prevent haze in wine.

  7. Galactomannan: a versatile biodegradable seed polysaccharide.

    Science.gov (United States)

    Prajapati, Vipul D; Jani, Girish K; Moradiya, Naresh G; Randeria, Narayan P; Nagar, Bhanu J; Naikwadi, Nikhil N; Variya, Bhavesh C

    2013-09-01

    Polysaccharides have been finding, in the last decades, very interesting and useful applications in the biomedical and, specifically, in the biopharmaceutical field. Galactomannans are a group of storage polysaccharides from various plant seeds that reserve energy for germination in the endosperm. There are four major sources of seed galactomannans: locust bean (Ceratonia siliqua), guar (Cyamopsis tetragonoloba), tara (Caesalpinia spinosa Kuntze), and fenugreek (Trigonella foenum-graecum L.). Through keen references of reported literature on galactomannans, in this review, we have described occurrence of various galactomannans, its physicochemical properties, characterization, applications, and overview of some major galactomannans.

  8. Studies on Sulfation of Lycium barbarum Polysaccharides

    Institute of Scientific and Technical Information of China (English)

    YI,Jian-Ping; YAN,Hong; ZHONG,Ru-Gang

    2004-01-01

    @@ Polysaccharides can anti-virus, such as human immunodeficiency virus (HIV-1),[1] herpes simplex virus (HSV-1,HSV-2) and cytomegalovirus. Some of them are sulfates, e.g. dextran sulfate, heparin, sulfonation of chitosan and sulfated derivatives of Lentinan. Our results showed that sulfated derivatives of Lycium barbarum polysaccharides (LBP)have anti-HIV activity. Because the anti-HIV activity of LBP was deeply dependent on the molecular weight, the sulfation pattern and glycosidic branches besides degree of sulfation (DS), so we emphasized our work on the factors of DS.

  9. Bacterial Adhesion & Blocking Bacterial Adhesion

    DEFF Research Database (Denmark)

    Vejborg, Rebecca Munk

    2008-01-01

    tract to the microbial flocs in waste water treatment facilities. Microbial biofilms may however also cause a wide range of industrial and medical problems, and have been implicated in a wide range of persistent infectious diseases, including implantassociated microbial infections. Bacterial adhesion...... is the first committing step in biofilm formation, and has therefore been intensely scrutinized. Much however, still remains elusive. Bacterial adhesion is a highly complex process, which is influenced by a variety of factors. In this thesis, a range of physico-chemical, molecular and environmental parameters......, which influence the transition from a planktonic lifestyle to a sessile lifestyle, have been studied. Protein conditioning film formation was found to influence bacterial adhesion and subsequent biofilm formation considerable, and an aqueous extract of fish muscle tissue was shown to significantly...

  10. Bacterial lipases

    NARCIS (Netherlands)

    Jaeger, Karl-Erich; Ransac, Stéphane; Dijkstra, Bauke W.; Colson, Charles; Heuvel, Margreet van; Misset, Onno

    1994-01-01

    Many different bacterial species produce lipases which hydrolyze esters of glycerol with preferably long-chain fatty acids. They act at the interface generated by a hydrophobic lipid substrate in a hydrophilic aqueous medium. A characteristic property of lipases is called interfacial activation, mea

  11. Enzymatic modification of bacterial exopolysaccharides; xanthan lyase as a tool for structural and functional modification of xanthan

    OpenAIRE

    Ruijssenaars, H.J.

    2001-01-01

    Bacterial extracellular polysaccharides (EPSs) can be applied, e.g., in foods, as a thickener or stabilizer. The functional properties that make a polysaccharide suitable for such applications are largely determined by the primary structure, i.e., the sugar composition, the linkage types between the sugar units, and the presence of side chains and non-sugar substituents. The aim of this research was to obtain EPS-modifying enzymes that could be used as tools both for studying structure-functi...

  12. Enzymatic production of hyaluronan oligo- and polysaccharides

    NARCIS (Netherlands)

    Kooy, F.K.

    2010-01-01

    Hyaluronan oligo- and polysaccharides are abundant in the human body. Depending on the chain length, hyaluronan is an important structural component or is involved in influencing cell responses during embryonic development, healing processes, inflammation and cancer. Due to these diverse roles of hy

  13. Bacterial Ecology

    DEFF Research Database (Denmark)

    Fenchel, Tom

    2011-01-01

    Bacterial ecology is concerned with the interactions between bacteria and their biological and nonbiological environments and with the role of bacteria in biogeochemical element cycling. Many fundamental properties of bacteria are consequences of their small size. Thus, they can efficiently exploit...... biogeochemical processes are carried exclusively by bacteria. * Bacteria play an important role in all types of habitats including some that cannot support eukaryotic life....

  14. Bacterial cellulose biosynthesis: diversity of operons, subunits, products and functions

    OpenAIRE

    Römling, Ute; Galperin, Michael Y

    2015-01-01

    Recent studies of bacterial cellulose biosynthesis, including structural characterization of a functional cellulose synthase complex, provided the first mechanistic insight into this fascinating process. In most studied bacteria, just two subunits, BcsA and BcsB, are necessary and sufficient for the formation of the polysaccharide chain in vitro. Other subunits – which differ among various taxa – affect the enzymatic activity and product yield in vivo by modulating expression of biosynthesis ...

  15. [Bacterial vaginosis].

    Science.gov (United States)

    Romero Herrero, Daniel; Andreu Domingo, Antonia

    2016-07-01

    Bacterial vaginosis (BV) is the main cause of vaginal dysbacteriosis in the women during the reproductive age. It is an entity in which many studies have focused for years and which is still open for discussion topics. This is due to the diversity of microorganisms that cause it and therefore, its difficult treatment. Bacterial vaginosis is probably the result of vaginal colonization by complex bacterial communities, many of them non-cultivable and with interdependent metabolism where anaerobic populations most likely play an important role in its pathogenesis. The main symptoms are an increase of vaginal discharge and the unpleasant smell of it. It can lead to serious consequences for women, such as an increased risk of contracting sexually transmitted infections including human immunodeficiency virus and upper genital tract and pregnancy complications. Gram stain is the gold standard for microbiological diagnosis of BV, but can also be diagnosed using the Amsel clinical criteria. It should not be considered a sexually transmitted disease but it is highly related to sex. Recurrence is the main problem of medical treatment. Apart from BV, there are other dysbacteriosis less characterized like aerobic vaginitis of which further studies are coming slowly but are achieving more attention and consensus among specialists. PMID:27474242

  16. Contribution of mono and polysaccharides to heterotrophic N2 fixation at the eastern Mediterranean coastline.

    Science.gov (United States)

    Rahav, E; Giannetto, M J; Bar-Zeev, E

    2016-01-01

    N2 fixation should be a critical process in the nitrogen-poor surface water of the eastern Mediterranean Sea. Despite favorable conditions, diazotroph abundance and N2 fixation rates remains low for reasons yet explained. The main goal of this study was to investigate the limiting nutrients for diazotrophy in this oligotrophic environment. Hence, we conducted dedicated bottle-microcosms with eastern Mediterranean Sea water that were supplemented with mono and polysaccharides as well as inorganic nitrogen and phosphorous. Our results indicate that the diazotrophic community expressing nifH was primarily represented by heterotrophic Proteobacteria. N2 fixation and heterotrophic bacterial activity increased up-to tenfold following two days of dark incubations, once seawater was supplemented with organic carbon substrate in the form of glucose (monosaccharides) or gum-xanthan (polysaccharide surrogate). Furthermore, our results point that carbon-rich polysaccharides, such as transparent exopolymer particles, enhance heterotrophic N2 fixation, by forming microenvironments of intense metabolic activity, high carbon: nitrogen ratio, and possibly low O2 levels. The conclusions of this study indicate that diazotrophs in the eastern Mediterranean coast are primarily limited by organic carbon substrates, as possibly in many other marine regions.

  17. A C4-oxidizing lytic polysaccharide monooxygenase cleaving both cellulose and cello-oligosaccharides.

    Science.gov (United States)

    Isaksen, Trine; Westereng, Bjørge; Aachmann, Finn L; Agger, Jane W; Kracher, Daniel; Kittl, Roman; Ludwig, Roland; Haltrich, Dietmar; Eijsink, Vincent G H; Horn, Svein J

    2014-01-31

    Lignocellulosic biomass is a renewable resource that significantly can substitute fossil resources for the production of fuels, chemicals, and materials. Efficient saccharification of this biomass to fermentable sugars will be a key technology in future biorefineries. Traditionally, saccharification was thought to be accomplished by mixtures of hydrolytic enzymes. However, recently it has been shown that lytic polysaccharide monooxygenases (LPMOs) contribute to this process by catalyzing oxidative cleavage of insoluble polysaccharides utilizing a mechanism involving molecular oxygen and an electron donor. These enzymes thus represent novel tools for the saccharification of plant biomass. Most characterized LPMOs, including all reported bacterial LPMOs, form aldonic acids, i.e., products oxidized in the C1 position of the terminal sugar. Oxidation at other positions has been observed, and there has been some debate concerning the nature of this position (C4 or C6). In this study, we have characterized an LPMO from Neurospora crassa (NcLPMO9C; also known as NCU02916 and NcGH61-3). Remarkably, and in contrast to all previously characterized LPMOs, which are active only on polysaccharides, NcLPMO9C is able to cleave soluble cello-oligosaccharides as short as a tetramer, a property that allowed detailed product analysis. Using mass spectrometry and NMR, we show that the cello-oligosaccharide products released by this enzyme contain a C4 gemdiol/keto group at the nonreducing end. PMID:24324265

  18. A C4-oxidizing Lytic Polysaccharide Monooxygenase Cleaving Both Cellulose and Cello-oligosaccharides*

    Science.gov (United States)

    Isaksen, Trine; Westereng, Bjørge; Aachmann, Finn L.; Agger, Jane W.; Kracher, Daniel; Kittl, Roman; Ludwig, Roland; Haltrich, Dietmar; Eijsink, Vincent G. H.; Horn, Svein J.

    2014-01-01

    Lignocellulosic biomass is a renewable resource that significantly can substitute fossil resources for the production of fuels, chemicals, and materials. Efficient saccharification of this biomass to fermentable sugars will be a key technology in future biorefineries. Traditionally, saccharification was thought to be accomplished by mixtures of hydrolytic enzymes. However, recently it has been shown that lytic polysaccharide monooxygenases (LPMOs) contribute to this process by catalyzing oxidative cleavage of insoluble polysaccharides utilizing a mechanism involving molecular oxygen and an electron donor. These enzymes thus represent novel tools for the saccharification of plant biomass. Most characterized LPMOs, including all reported bacterial LPMOs, form aldonic acids, i.e., products oxidized in the C1 position of the terminal sugar. Oxidation at other positions has been observed, and there has been some debate concerning the nature of this position (C4 or C6). In this study, we have characterized an LPMO from Neurospora crassa (NcLPMO9C; also known as NCU02916 and NcGH61–3). Remarkably, and in contrast to all previously characterized LPMOs, which are active only on polysaccharides, NcLPMO9C is able to cleave soluble cello-oligosaccharides as short as a tetramer, a property that allowed detailed product analysis. Using mass spectrometry and NMR, we show that the cello-oligosaccharide products released by this enzyme contain a C4 gemdiol/keto group at the nonreducing end. PMID:24324265

  19. Contribution of mono and polysaccharides to heterotrophic N2 fixation at the eastern Mediterranean coastline.

    Science.gov (United States)

    Rahav, E; Giannetto, M J; Bar-Zeev, E

    2016-01-01

    N2 fixation should be a critical process in the nitrogen-poor surface water of the eastern Mediterranean Sea. Despite favorable conditions, diazotroph abundance and N2 fixation rates remains low for reasons yet explained. The main goal of this study was to investigate the limiting nutrients for diazotrophy in this oligotrophic environment. Hence, we conducted dedicated bottle-microcosms with eastern Mediterranean Sea water that were supplemented with mono and polysaccharides as well as inorganic nitrogen and phosphorous. Our results indicate that the diazotrophic community expressing nifH was primarily represented by heterotrophic Proteobacteria. N2 fixation and heterotrophic bacterial activity increased up-to tenfold following two days of dark incubations, once seawater was supplemented with organic carbon substrate in the form of glucose (monosaccharides) or gum-xanthan (polysaccharide surrogate). Furthermore, our results point that carbon-rich polysaccharides, such as transparent exopolymer particles, enhance heterotrophic N2 fixation, by forming microenvironments of intense metabolic activity, high carbon: nitrogen ratio, and possibly low O2 levels. The conclusions of this study indicate that diazotrophs in the eastern Mediterranean coast are primarily limited by organic carbon substrates, as possibly in many other marine regions. PMID:27306501

  20. Reprint of: Nitric oxide-releasing polysaccharide derivative exhibits 8-log reduction against Escherichia coli, Acinetobacter baumannii and Staphylococcus aureus.

    Science.gov (United States)

    Pegalajar-Jurado, Adoracion; Wold, Kathryn A; Joslin, Jessica M; Neufeld, Bella H; Arabea, Kristin A; Suazo, Lucas A; McDaniel, Stephen L; Bowen, Richard A; Reynolds, Melissa M

    2015-12-28

    Health-care associated infections (HAIs) and the increasing number of antibiotic-resistant bacteria strains remain significant public health threats worldwide. Although the number of HAIs has decreased by using improved sterilization protocols, the cost related to HAIs is still quantified in billions of dollars. Furthermore, the development of multi-drug resistant strains is increasing exponentially, demonstrating that current treatments are inefficient. Thus, the quest for new methods to eradicate bacterial infection is increasingly important in antimicrobial, drug delivery and biomaterials research. Herein, the bactericidal activity of a water-soluble NO-releasing polysaccharide derivative was evaluated in nutrient broth media against three bacteria strains that are commonly responsible for HAIs. Data confirmed that this NO-releasing polysaccharide derivative induced an 8-log reduction in bacterial growth after 24h for Escherichia coli, Acinetobacter baumannii and Staphylococcus aureus. Additionally, the absence of bacteria after 72 h of exposure to NO illustrates the inability of the bacteria to recover and the prevention of biofilm formation. The presented 8-log reduction in bacterial survival after 24h is among the highest reduction reported for NO delivery systems to date, and reaches the desired standard for industrially-relevant reduction. More specifically, this system represents the only water-soluble antimicrobial to reach such a significant bacterial reduction in nutrient rich media, wherein experimental conditions more closely mimic the in vivo environment than those in previous reports. Furthermore, the absence of bacterial activity after 72 h and the versatility of using a water-soluble compound suggest that this NO-releasing polysaccharide derivative is a promising route for treating HAIs.

  1. The clinical impact of bacterial biofilms

    DEFF Research Database (Denmark)

    Høiby, Niels; Ciofu, Oana; Johansen, Helle Krogh;

    2011-01-01

    Bacteria survive in nature by forming biofilms on surfaces and probably most, if not all, bacteria (and fungi) are capable of forming biofilms. A biofilm is a structured consortium of bacteria embedded in a self-produced polymer matrix consisting of polysaccharide, protein and extracellular DNA....... Bacterial biofilms are resistant to antibiotics, disinfectant chemicals and to phagocytosis and other components of the innate and adaptive inflammatory defense system of the body. It is known, for example, that persistence of staphylococcal infections related to foreign bodies is due to biofilm formation....... Likewise, chronic Pseudomonas aeruginosa lung infections in cystic fibrosis patients are caused by biofilm growing mucoid strains. Gradients of nutrients and oxygen exist from the top to the bottom of biofilms and the bacterial cells located in nutrient poor areas have decreased metabolic activity...

  2. Immunization of newborns with bacterial conjugate vaccines.

    Science.gov (United States)

    van den Biggelaar, Anita H J; Pomat, William S

    2013-05-17

    Bacterial conjugate vaccines are based on the principle of coupling immunogenic bacterial capsular polysaccharides to a carrier protein to facilitate the induction of memory T-cell responses. Following the success of Haemophilus influenzae type b conjugate vaccines in the 1980s, conjugate vaccines for Streptococcus pneumoniae and Neisseria meningitidis infections were developed and proven to be effective in protecting children against invasive disease. In this review, the use of conjugate vaccines in human newborns is discussed. Neonatal Haemophilus influenzae type b and pneumococcal conjugate vaccination schedules have been trialed and proven to be safe, with the majority of studies demonstrating no evidence for the induction of immune tolerance. Whether their neonatal administration also results in an earlier induction of clinical protection in the first 2-3 critical months of life is still to be demonstrated. PMID:22728221

  3. The Vi capsular polysaccharide enables Salmonella enterica serovar typhi to evade microbe-guided neutrophil chemotaxis.

    Directory of Open Access Journals (Sweden)

    Tamding Wangdi

    2014-08-01

    Full Text Available Salmonella enterica serovar Typhi (S. Typhi causes typhoid fever, a disseminated infection, while the closely related pathogen S. enterica serovar Typhimurium (S. Typhimurium is associated with a localized gastroenteritis in humans. Here we investigated whether both pathogens differ in the chemotactic response they induce in neutrophils using a single-cell experimental approach. Surprisingly, neutrophils extended chemotactic pseudopodia toward Escherichia coli and S. Typhimurium, but not toward S. Typhi. Bacterial-guided chemotaxis was dependent on the presence of complement component 5a (C5a and C5a receptor (C5aR. Deletion of S. Typhi capsule biosynthesis genes markedly enhanced the chemotactic response of neutrophils in vitro. Furthermore, deletion of capsule biosynthesis genes heightened the association of S. Typhi with neutrophils in vivo through a C5aR-dependent mechanism. Collectively, these data suggest that expression of the virulence-associated (Vi capsular polysaccharide of S. Typhi obstructs bacterial-guided neutrophil chemotaxis.

  4. The Vi capsular polysaccharide enables Salmonella enterica serovar typhi to evade microbe-guided neutrophil chemotaxis.

    Science.gov (United States)

    Wangdi, Tamding; Lee, Cheng-Yuk; Spees, Alanna M; Yu, Chenzhou; Kingsbury, Dawn D; Winter, Sebastian E; Hastey, Christine J; Wilson, R Paul; Heinrich, Volkmar; Bäumler, Andreas J

    2014-08-01

    Salmonella enterica serovar Typhi (S. Typhi) causes typhoid fever, a disseminated infection, while the closely related pathogen S. enterica serovar Typhimurium (S. Typhimurium) is associated with a localized gastroenteritis in humans. Here we investigated whether both pathogens differ in the chemotactic response they induce in neutrophils using a single-cell experimental approach. Surprisingly, neutrophils extended chemotactic pseudopodia toward Escherichia coli and S. Typhimurium, but not toward S. Typhi. Bacterial-guided chemotaxis was dependent on the presence of complement component 5a (C5a) and C5a receptor (C5aR). Deletion of S. Typhi capsule biosynthesis genes markedly enhanced the chemotactic response of neutrophils in vitro. Furthermore, deletion of capsule biosynthesis genes heightened the association of S. Typhi with neutrophils in vivo through a C5aR-dependent mechanism. Collectively, these data suggest that expression of the virulence-associated (Vi) capsular polysaccharide of S. Typhi obstructs bacterial-guided neutrophil chemotaxis.

  5. Effects of low-level laser therapy combined with toluidine blue on polysaccharides and biofilm of Streptococcus mutans.

    Science.gov (United States)

    de Sousa Farias, S S; Nemezio, M A; Corona, S A M; Aires, C P; Borsatto, M C

    2016-07-01

    The aim of this study was to evaluate the effect of a low-level laser therapy in combination with toluidine blue on polysaccharides and biofilm of Streptococcus mutans. S. mutans biofilms were formed on acrylic resin blocks. These biofilms were exposed eight times/day to 10 % sucrose, and two times/day, they were subjected to one of the following treatments: G1, 0.9 % NaCl as a negative control; G2, 0.12 % chlorhexidine digluconate (CHX) as a positive antibacterial control; and G3 and G4 antimicrobial photodynamic therapy (aPDT) combined with toluidine blue using dosages of 320 and 640 J/cm(2), respectively. The experiment was performed in triplicate. The biofilm formed on each block was collected for determination of the viable bacteria and concentration of insoluble extracellular polysaccharides (IEPS) and intracellular polysaccharides (IPS). CHX and aPDT treatments were able to inhibit bacterial growth in comparison with negative control (p  0.05). The results suggest that low-level laser therapy presents effects on biofilm bacteria viability and in polysaccharides concentration. PMID:27147073

  6. Influence of O polysaccharides on biofilm development and outer membrane vesicle biogenesis in Pseudomonas aeruginosa PAO1.

    Science.gov (United States)

    Murphy, Kathleen; Park, Amber J; Hao, Youai; Brewer, Dyanne; Lam, Joseph S; Khursigara, Cezar M

    2014-04-01

    Pseudomonas aeruginosa is a common opportunistic human pathogen known for its ability to adapt to changes in its environment during the course of infection. These adaptations include changes in the expression of cell surface lipopolysaccharide (LPS), biofilm development, and the production of a protective extracellular exopolysaccharide matrix. Outer membrane vesicles (OMVs) have been identified as an important component of the extracellular matrix of P. aeruginosa biofilms and are thought to contribute to the development and fitness of these bacterial communities. The goal of this study was to examine the relationships between changes in the cell surface expression of LPS O polysaccharides, biofilm development, and OMV biogenesis in P. aeruginosa. We compared wild-type P. aeruginosa PAO1 with three chromosomal knockouts. These knockouts have deletions in the rmd, wbpM, and wbpL genes that produce changes in the expression of common polysaccharide antigen (CPA), O-specific antigen (OSA), or both. Our results demonstrate that changes in O polysaccharide expression do not significantly influence OMV production but do affect the size and protein content of OMVs derived from both CPA(-) and OSA(-) cells; these mutant cells also exhibited different physical properties from wild-type cells. We further examined biofilm growth of the mutants and determined that CPA(-) cells could not develop into robust biofilms and exhibit changes in cell morphology and biofilm matrix production. Together these results demonstrate the importance of O polysaccharide expression on P. aeruginosa OMV composition and highlight the significance of CPA expression in biofilm development. PMID:24464462

  7. POLYPEPTIDE AND POLYSACCHARIDE PROCESSING IN HYPERTHERMOPHILIC MICROORGANISMS

    Energy Technology Data Exchange (ETDEWEB)

    KELLY, ROBERT M.

    2008-12-22

    This project focused on the microbial physiology and biochemistry of heterotrophic hyperthermophiles with respect to mechanisms by which these organisms process polypeptides and polysaccharides under normal and stressed conditions. Emphasis is on two model organisms, for which completed genome sequences are available: Pyrococcus furiosus (growth Topt of 98°C), an archaeon, and Thermotoga maritima (growth Topt of 80°C), a bacterium. Both organisms are obligately anaerobic heterotrophs that reduce sulfur facultatively. Whole genome cDNA spotted microarrays were used to follow transcriptional response to a variety of environmental conditions in order to identify genes encoding proteins involved in the acquisition, synthesis, processing and utilization of polypeptides and polysaccharides. This project provided new insights into the physiological aspects of hyperthermophiles as these relate to microbial biochemistry and biological function in high temperature habitats. The capacity of these microorganisms to produce biohydrogen from renewable feedstocks makes them important for future efforts to develop biofuels.

  8. Polysaccharides: The “Click” Chemistry Impact

    OpenAIRE

    Romain Lucas; Daniel Montplaisir; Rachida Zerrouki; Pierre-Antoine Faugeras; François Brouillette; Benjamin Boëns; Pierre-Henri Elchinger

    2011-01-01

    Polysaccharides are complex but essential compounds utilized in many areas such as biomaterials, drug delivery, cosmetics, food chemistry or renewable energy. Modifications and functionalizations of such polymers are often necessary to achieve molecular structures of interest. In this area, the emergence of the “click” chemistry concept, and particularly the copper-catalyzed version of the Huisgen 1,3-dipolar cycloaddition reaction between terminal acetylenes and azides, had an impact on the ...

  9. Marine origin polysaccharides in drug delivery systems

    OpenAIRE

    Matias J. Cardoso; Costa, Rui R.; Mano, João F.

    2016-01-01

    Oceans are a vast source of natural substances. In them, we find various compounds with wide biotechnological and biomedical applicabilities. The exploitation of the sea as a renewable source of biocompounds can have a positive impact on the development of new systems and devices for biomedical applications. Marine polysaccharides are among the most abundant materials in the seas, which contributes to a decrease of the extraction costs, besides their solubility behavior in aqueous solvents an...

  10. Wzy-dependent bacterial capsules as potential drug targets.

    Science.gov (United States)

    Ericsson, Daniel J; Standish, Alistair; Kobe, Bostjan; Morona, Renato

    2012-10-01

    The bacterial capsule is a recognized virulence factor in pathogenic bacteria. It likely works as an antiphagocytic barrier by minimizing complement deposition on the bacterial surface. With the continual rise of bacterial pathogens resistant to multiple antibiotics, there is an increasing need for novel drugs. In the Wzy-dependent pathway, the biosynthesis of capsular polysaccharide (CPS) is regulated by a phosphoregulatory system, whose main components consist of bacterial-tyrosine kinases (BY-kinases) and their cognate phosphatases. The ability to regulate capsule biosynthesis has been shown to be vital for pathogenicity, because different stages of infection require a shift in capsule thickness, making the phosphoregulatory proteins suitable as drug targets. Here, we review the role of regulatory proteins focusing on Streptococcus pneumoniae, Staphylococcus aureus, and Escherichia coli and discuss their suitability as targets in structure-based drug design.

  11. The dietary polysaccharide maltodextrin promotes Salmonella survival and mucosal colonization in mice.

    Directory of Open Access Journals (Sweden)

    Kourtney P Nickerson

    Full Text Available In the latter half of the 20th century, societal and technological changes led to a shift in the composition of the American diet to include a greater proportion of processed, pre-packaged foods high in fat and carbohydrates, and low in dietary fiber (a "Western diet". Over the same time period, there have been parallel increases in Salmonella gastroenteritis cases and a broad range of chronic inflammatory diseases associated with intestinal dysbiosis. Several polysaccharide food additives are linked to bacterially-driven intestinal inflammation and may contribute to the pathogenic effects of a Western diet. Therefore, we examined the effect of a ubiquitous polysaccharide food additive, maltodextrin (MDX, on clearance of the enteric pathogen Salmonella using both in vitro and in vivo infection models. When examined in vitro, murine bone marrow-derived macrophages exposed to MDX had altered vesicular trafficking, suppressed NAPDH oxidase expression, and reduced recruitment of NADPH oxidase to Salmonella-containing vesicles, which resulted in persistence of Salmonella in enlarged Rab7+ late endosomal vesicles. In vivo, mice consuming MDX-supplemented water had a breakdown of the anti-microbial mucous layer separating gut bacteria from the intestinal epithelium surface. Additionally, oral infection of these mice with Salmonella resulted in increased cecal bacterial loads and enrichment of lamina propria cells harboring large Rab7+ vesicles. These findings indicate that consumption of processed foods containing the polysaccharide MDX contributes to suppression of intestinal anti-microbial defense mechanisms and may be an environmental priming factor for the development of chronic inflammatory disease.

  12. Plant Cell Wall Matrix Polysaccharide Biosynthesis

    Institute of Scientific and Technical Information of China (English)

    Ajay Pal S. Sandhu; Gursharn S. Randhawa; Kanwarpal S. Dhugga

    2009-01-01

    The wall of an expanding plant cell consists primarily of cellulose microfibrils embedded in a matrix of hemi-cellulosic and pectic polysaccharides along with small amounts of structural and enzymatic proteins. Matrix polysacchar-ides are synthesized in the Golgi and exported to the cell wall by exocytosis, where they intercalate among cellulose microfibrUs, which are made at the plasma membrane and directly deposited into the cell wall. Involvement of Golgi glucan synthesis in auxin-induced cell expansion has long been recognized; however, only recently have the genes corresponding to glucan synthases been identified. Biochemical purification was unsuccessful because of the labile nature and very low abundance of these enzymes. Mutational genetics also proved fruitless. Expression of candidate genes identified through gene expression profiling or comparative genomics in heterologous systems followed by functional characterization has been relatively successful. Several genes from the cellulose synthase-like (Cs/) family have been found to be involved in the synthesis of various hemicellulosic glycans. The usefulness of this approach, however, is limited to those enzymes that probably do not form complexes consisting of unrelated proteins. Nonconventional approaches will continue to incre-mentally unravel the mechanisms of Golgi polysaccharide biosynthesis.

  13. Marine Origin Polysaccharides in Drug Delivery Systems

    Directory of Open Access Journals (Sweden)

    Matias J. Cardoso

    2016-02-01

    Full Text Available Oceans are a vast source of natural substances. In them, we find various compounds with wide biotechnological and biomedical applicabilities. The exploitation of the sea as a renewable source of biocompounds can have a positive impact on the development of new systems and devices for biomedical applications. Marine polysaccharides are among the most abundant materials in the seas, which contributes to a decrease of the extraction costs, besides their solubility behavior in aqueous solvents and extraction media, and their interaction with other biocompounds. Polysaccharides such as alginate, carrageenan and fucoidan can be extracted from algae, whereas chitosan and hyaluronan can be obtained from animal sources. Most marine polysaccharides have important biological properties such as biocompatibility, biodegradability, and anti-inflammatory activity, as well as adhesive and antimicrobial actions. Moreover, they can be modified in order to allow processing them into various shapes and sizes and may exhibit response dependence to external stimuli, such as pH and temperature. Due to these properties, these biomaterials have been studied as raw material for the construction of carrier devices for drugs, including particles, capsules and hydrogels. The devices are designed to achieve a controlled release of therapeutic agents in an attempt to fight against serious diseases, and to be used in advanced therapies, such as gene delivery or regenerative medicine.

  14. M-ficolin binds selectively to the capsular polysaccharides of Streptococcus pneumoniae serotypes 19B and 19C and of a S. mitis strain

    DEFF Research Database (Denmark)

    Kjær, Troels Rønn; Hansen, Annette G; Sørensen, Uffe B S;

    2012-01-01

    of infections. We investigated the binding selectivity by examining the binding of M-ficolin to a panel of more than 100 different streptococcal strains (Streptococcus pneumoniae and Streptococcus mitis) each expressing distinct polysaccharide structures. M-ficolin binding was observed for three strains only......, the pneumococcal serotypes 19B and 19C and a single mitis strain expressing a similar polysaccharide structure. The bound M-ficolin, in association with MASP-2, mediated complement factor C4 cleavage. Binding to the bacteria was inhibitable by N-acetyl glucosamine indicating that the interaction with the bacterial...... surface takes place via the fibrinogen-like domain. The common N-acetyl mannosamine residue present in the structures of the four capsular polysaccharides of group 19 is linked via a phosphodiester bond. This residue is apparently not a ligand for M-ficolin since the lectin binds to two of the group 19...

  15. Evaluation of phosphorylated psyllium seed polysaccharide as a release retardant

    Directory of Open Access Journals (Sweden)

    Monica R P Rao

    2015-01-01

    Full Text Available The aim of the present study was to modify psyllium seed polysaccharide and evaluate the modified polysaccharide as release retardant in tablets employing ciprofloxacin hydrochloride as model drug. Studies on polysaccharide from psyllium husk has been reported but no work has been reported on characterization and modification of the polysaccharide present in the psyllium (Plantago ovata seed and the use of the modified polysaccharide as a release retardant in tablets. In this study, the seed gum was modified using sodium trimetaphosphate as crosslinking agent. Sustained release matrix tablets of ciprofloxacin hydrochloride were prepared by wet granulation using various drug-polymer ratios. The polymers investigated were psyllium polysaccharide, phosphorylated psyllium polysaccharide and widely used release retardant hydroxypropyl methylcellulose K100M. The tablets were evaluated for hardness, friability, drug content, swelling profile and in vitro dissolution studies. The matrix tablets containing 1:3 proportion of drug-phosphorylated psyllium polysaccharide was found to have higher hardness as compared to tablets containing 1:1 and 1:2 proportions. The results of swelling behavior in water showed that the tablets containing 1:3 drug:phosphorylated psyllium polysaccharide ratio had swelling comparable to that of tablets containing 1:3 drug:hydroxypropyl methylcellulose ratio. The in vitro dissolution studies shows that the dissolution rate was retarded from 98.41 to 37.6% in 6 h with increase in concentration of phosphorylated psyllium polysaccharide from 100 to 300 mg. Formulations containing psyllium polysaccharide showed complete drug release in 8 h whereas those formulated with phosphorylated psyllium polysaccharide exhibited extended drug release over the 12 h period. Drug release kinetic studies revealed that drug release followed Korsmeyer-Peppas model.

  16. Evaluation of Phosphorylated Psyllium Seed Polysaccharide as a Release Retardant.

    Science.gov (United States)

    Rao, Monica R P; Warrier, Deepa U; Rao, Shivani H

    2015-01-01

    The aim of the present study was to modify psyllium seed polysaccharide and evaluate the modified polysaccharide as release retardant in tablets employing ciprofloxacin hydrochloride as model drug. Studies on polysaccharide from psyllium husk has been reported but no work has been reported on characterization and modification of the polysaccharide present in the psyllium (Plantago ovata) seed and the use of the modified polysaccharide as a release retardant in tablets. In this study, the seed gum was modified using sodium trimetaphosphate as crosslinking agent. Sustained release matrix tablets of ciprofloxacin hydrochloride were prepared by wet granulation using various drug-polymer ratios. The polymers investigated were psyllium polysaccharide, phosphorylated psyllium polysaccharide and widely used release retardant hydroxypropyl methylcellulose K100M. The tablets were evaluated for hardness, friability, drug content, swelling profile and in vitro dissolution studies. The matrix tablets containing 1:3 proportion of drug-phosphorylated psyllium polysaccharide was found to have higher hardness as compared to tablets containing 1:1 and 1:2 proportions. The results of swelling behavior in water showed that the tablets containing 1:3 drug:phosphorylated psyllium polysaccharide ratio had swelling comparable to that of tablets containing 1:3 drug:hydroxypropyl methylcellulose ratio. The in vitro dissolution studies shows that the dissolution rate was retarded from 98.41 to 37.6% in 6 h with increase in concentration of phosphorylated psyllium polysaccharide from 100 to 300 mg. Formulations containing psyllium polysaccharide showed complete drug release in 8 h whereas those formulated with phosphorylated psyllium polysaccharide exhibited extended drug release over the 12 h period. Drug release kinetic studies revealed that drug release followed Korsmeyer-Peppas model. PMID:26798177

  17. Structural Analysis of Polysaccharide from Cladonia furcatar and Its Activities

    Institute of Scientific and Technical Information of China (English)

    CHEN Qian; LIN Xin; CAI YuJun; LI ZhiXiao

    2001-01-01

    @@ Cladonia furcatar is a member of the lichens genus Cladonia. Japanese scientific researchers [1] made a great achievement in selecting lichens as anticancer agent and polysaccharides are generally considered to be their main bioactive constituents. Recently, Iacomini et al[2] have investigated the members of the genus Cladonia, a mannose-containing polysaccharide was isolated from Cladoniafurcatar. We now report the new chemical structure of polysaccharide from Cladoniafurcatar and its activities.

  18. Structural Analysis of Polysaccharide from Cladonia furcatar and Its Activities

    Institute of Scientific and Technical Information of China (English)

    CHEN; Qian

    2001-01-01

    Cladonia furcatar is a member of the lichens genus Cladonia. Japanese scientific researchers [1] made a great achievement in selecting lichens as anticancer agent and polysaccharides are generally considered to be their main bioactive constituents. Recently, Iacomini et al[2] have investigated the members of the genus Cladonia, a mannose-containing polysaccharide was isolated from Cladoniafurcatar. We now report the new chemical structure of polysaccharide from Cladoniafurcatar and its activities.  ……

  19. The S. aureus polysaccharide capsule and Efb-dependent fibrinogen shield act in concert to protect against phagocytosis

    Science.gov (United States)

    Kuipers, Annemarie; Stapels, Daphne A. C.; Weerwind, Lleroy T.; Ko, Ya-Ping; Ruyken, Maartje; Lee, Jean C.; van Kessel, Kok P.M.; Rooijakkers, Suzan H. M.

    2016-01-01

    Staphylococcus aureus has developed many mechanisms to escape from human immune responses. In order to resist phagocytic clearance, S. aureus expresses a polysaccharide capsule, which effectively masks the bacterial surface and surface-associated proteins, such as opsonins, from recognition by phagocytic cells. Additionally, secretion of the Extracellular fibrinogen binding protein (Efb) potently blocks phagocytic uptake of the pathogen. Efb creates a fibrinogen shield surrounding the bacteria by simultaneously binding complement C3b and fibrinogen at the bacterial surface. By means of neutrophil phagocytosis assays with fluorescently labeled encapsulated serotype 5 (CP5) and serotype 8 (CP8) strains we now compare the immune-modulating function of these shielding mechanisms. Our data indicate that, in highly encapsulated S. aureus strains, the polysaccharide capsule is able to prevent phagocytic uptake at plasma concentrations <10%, but loses its protective ability at higher concentrations of plasma. Interestingly, Efb shows a strong inhibitory effect on both capsule-negative as well as encapsulated strains at all tested plasma concentrations. Furthermore our results suggest that both shielding mechanisms can exist simultaneously and collaborate to provide optimal protection against phagocytosis at a broad range of plasma concentrations. Since opsonizing antibodies will be shielded from recognition by either mechanism, incorporating both capsular polysaccharides and Efb in future vaccines could be of great importance. PMID:27112346

  20. [Improvement on microwave technology of extracting polysaccharide from yacon leaves].

    Science.gov (United States)

    Li, Jing-wei; Liu, Jian; Yang, Yong; Zheng, Ming-min; Rong, Ting-zhao

    2007-11-01

    According to the extraction ratio of polysaccharide in yacon leaves, the comparison between microwave extraction and traditional hot water extraction was conducted, and the two-factor and three-level experiment on the microwave extraction of polysaccharide from yacon leaves was investigated. The result showed that the extraction ratio of polysaccharide by using microwave extraction was better than that by using traditional hot water extraction. Moreover, according to the result of variance analysis and multiple comparison, the optimum conditions for extraction of polysaccharide by using microwave technology from yacon leaves were as follows: 280W microwave power for 2 times and 15 minutes at every time. PMID:18323219

  1. Antiviral polysaccharides isolated from Hong Kong brown seaweed Hydroclathrus clathratus

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    Two relatively pure polysaccharides H3-a1 and H3-b1 had been isolated from the brown seaweed Hydroclathrus clathratus. They were characterized by HPLC, ultraviolet scanning, gas chromatography, infrared spectroscopy and elemental analysis, and shown to be two different sulfated polysaccharides with different monosaccharide content, but both with high relative molecular mass. They contained some proteins and uronic acid respectively. The sulfate content and bioactivity of these polysaccharides varied during purification. The fractions derived from the hot water extract also exhibited low anticoagulant effect. This is the first time that the antiherpetic and anticoagulant activities were evaluated for the polysaccharides from the Hong Kong brown seaweed Hydroclathrus clathratus.

  2. Bacterial Hydrodynamics

    Science.gov (United States)

    Lauga, Eric

    2016-01-01

    Bacteria predate plants and animals by billions of years. Today, they are the world's smallest cells, yet they represent the bulk of the world's biomass and the main reservoir of nutrients for higher organisms. Most bacteria can move on their own, and the majority of motile bacteria are able to swim in viscous fluids using slender helical appendages called flagella. Low-Reynolds number hydrodynamics is at the heart of the ability of flagella to generate propulsion at the micrometer scale. In fact, fluid dynamic forces impact many aspects of bacteriology, ranging from the ability of cells to reorient and search their surroundings to their interactions within mechanically and chemically complex environments. Using hydrodynamics as an organizing framework, I review the biomechanics of bacterial motility and look ahead to future challenges.

  3. Bacterial hydrodynamics

    CERN Document Server

    Lauga, Eric

    2015-01-01

    Bacteria predate plants and animals by billions of years. Today, they are the world's smallest cells yet they represent the bulk of the world's biomass, and the main reservoir of nutrients for higher organisms. Most bacteria can move on their own, and the majority of motile bacteria are able to swim in viscous fluids using slender helical appendages called flagella. Low-Reynolds-number hydrodynamics is at the heart of the ability of flagella to generate propulsion at the micron scale. In fact, fluid dynamic forces impact many aspects of bacteriology, ranging from the ability of cells to reorient and search their surroundings to their interactions within mechanically and chemically-complex environments. Using hydrodynamics as an organizing framework, we review the biomechanics of bacterial motility and look ahead to future challenges.

  4. Extraction, chemical analysis of Angelica sinensis polysaccharides and antioxidant activity of the polysaccharides in ischemia-reperfusion rats.

    Science.gov (United States)

    Zhang, Song; He, Ben; Ge, Junbo; Li, Huibin; Luo, Xiuying; Zhang, Hui; Li, Yuhui; Zhai, Changlin; Liu, Pingang; Liu, Xin; Fei, Xuetao

    2010-11-01

    Angelica sinensis polysaccharides were analyzed using high performance liquid chromatography (HPLC) and Fourier Transform Infrared (FT-IR). The major sugar of the polysaccharide was saccharose (18.55%); and the sugar constituted about 83% of the monomer content. Glucose and fructose were found as minor components of the polysaccharides. The FT-IR spectra of A. sinensis polysaccharides are used for determination of their structural features. The FT-IR spectrum of A. sinensis polysaccharides showed bands at 1641 cm(-1), 1415 cm(-1), 1050 cm(-1) and 926 cm(-1) characteristic for the carboxylic group. Absorptions at 2920-2930 cm(-1) are attributed to asymmetrical stretching vibration of CH(2)-group. Medium stretch observed in the range 1650-1400 cm(-1) is assigned to C-C stretching of polysaccharides. Cardioprotective effects of A. sinensis polysaccharides were evaluated by using myocardial ischemia/reperfusion (IR) rats. A. sinensis polysaccharides treatment significantly reduced myocardial infarction size, enhanced CT-1 and antioxidant enzymes activity, downregulated caspase-12 mRNA expression in rats. The study strongly suggests the cardioprotective activity of A. sinensis polysaccharides in limiting ischemia-reperfusion induced myocardial injury. PMID:20691723

  5. Bacterial enzymes involved in lignin degradation.

    Science.gov (United States)

    de Gonzalo, Gonzalo; Colpa, Dana I; Habib, Mohamed H M; Fraaije, Marco W

    2016-10-20

    Lignin forms a large part of plant biomass. It is a highly heterogeneous polymer of 4-hydroxyphenylpropanoid units and is embedded within polysaccharide polymers forming lignocellulose. Lignin provides strength and rigidity to plants and is rather resilient towards degradation. To improve the (bio)processing of lignocellulosic feedstocks, more effective degradation methods of lignin are in demand. Nature has found ways to fully degrade lignin through the production of dedicated ligninolytic enzyme systems. While such enzymes have been well thoroughly studied for ligninolytic fungi, only in recent years biochemical studies on bacterial enzymes capable of lignin modification have intensified. This has revealed several types of enzymes available to bacteria that enable them to act on lignin. Two major classes of bacterial lignin-modifying enzymes are DyP-type peroxidases and laccases. Yet, recently also several other bacterial enzymes have been discovered that seem to play a role in lignin modifications. In the present review, we provide an overview of recent advances in the identification and use of bacterial enzymes acting on lignin or lignin-derived products. PMID:27544286

  6. Evaluation of polysaccharides content in fruit bodies and their antimicrobial activity of four Ganoderma lucidum (W Curt.: Fr. P. Karst. strains cultivated on different wood type substrates

    Directory of Open Access Journals (Sweden)

    Krystyna Skalicka-Woźniak

    2012-03-01

    Full Text Available Quantitative determination of polysaccharides in Ganoderma lucidum fruit bodies from different sawdust cultivation substrates and their antibacterial activity was done. Thirty six samples were analyzed. Four strains of Ganoderma lucidum (GL01, GL02, GL03 and GL04 were cultivated on the growth substrates of three different sawdust types: birch (Bo, maple (Kl or alder (Ol amended with wheat bran in three different concentrations: 10, 20 and 30% (w/w. Even though the richest in polysaccharides was GL01 strain, the highest yields of the polysaccharides were determined in GL04Kl3 sample and was 112.82 mg/g of dry weight. The antibacterial activity of polysaccharides was determined in vitro using micro-dilution broth method. The panel of eight reference bacterial strains was used. All the polysaccharide samples tested showed the broad spectrum and the moderate antibacterial activity. Micrococcus luteus ATCC 10240 strain was the most sensitive with MIC (minimal inhibitory concentration = 0.63 − 1.25 mg/mL.

  7. Immunomodulatory dietary polysaccharides: a systematic review of the literature

    Directory of Open Access Journals (Sweden)

    Nelson Erika D

    2010-11-01

    Full Text Available Abstract Background A large body of literature suggests that certain polysaccharides affect immune system function. Much of this literature, however, consists of in vitro studies or studies in which polysaccharides were injected. Their immunologic effects following oral administration is less clear. The purpose of this systematic review was to consolidate and evaluate the available data regarding the specific immunologic effects of dietary polysaccharides. Methods Studies were identified by conducting PubMed and Google Scholar electronic searches and through reviews of polysaccharide article bibliographies. Only articles published in English were included in this review. Two researchers reviewed data on study design, control, sample size, results, and nature of outcome measures. Subsequent searches were conducted to gather information about polysaccharide safety, structure and composition, and disposition. Results We found 62 publications reporting statistically significant effects of orally ingested glucans, pectins, heteroglycans, glucomannans, fucoidans, galactomannans, arabinogalactans and mixed polysaccharide products in rodents. Fifteen controlled human studies reported that oral glucans, arabinogalactans, heteroglycans, and fucoidans exerted significant effects. Although some studies investigated anti-inflammatory effects, most studies investigated the ability of oral polysaccharides to stimulate the immune system. These studies, as well as safety and toxicity studies, suggest that these polysaccharide products appear to be largely well-tolerated. Conclusions Taken as a whole, the oral polysaccharide literature is highly heterogenous and is not sufficient to support broad product structure/function generalizations. Numerous dietary polysaccharides, particularly glucans, appear to elicit diverse immunomodulatory effects in numerous animal tissues, including the blood, GI tract and spleen. Glucan extracts from the Trametes versicolor

  8. PssP2 is a polysaccharide co-polymerase involved in exopolysaccharide chain-length determination in Rhizobium leguminosarum.

    Directory of Open Access Journals (Sweden)

    Małgorzata Marczak

    Full Text Available Production of extracellular polysaccharides is a complex process engaging proteins localized in different subcellular compartments, yet communicating with each other or even directly interacting in multicomponent complexes. Proteins involved in polymerization and transport of exopolysaccharide (EPS in Rhizobium leguminosarum are encoded within the chromosomal Pss-I cluster. However, genes implicated in polysaccharide synthesis are common in rhizobia, with several homologues of pss genes identified in other regions of the R. leguminosarum genome. One such region is chromosomally located Pss-II encoding proteins homologous to known components of the Wzx/Wzy-dependent polysaccharide synthesis and transport systems. The pssP2 gene encodes a protein similar to polysaccharide co-polymerases involved in determination of the length of polysaccharide chains in capsule and O-antigen biosynthesis. In this work, a mutant with a disrupted pssP2 gene was constructed and its capabilities to produce EPS and enter into a symbiotic relationship with clover were studied. The pssP2 mutant, while not altered in lipopolysaccharide (LPS, displayed changes in molecular mass distribution profile of EPS. Lack of the full-length PssP2 protein resulted in a reduction of high molecular weight EPS, yet polymerized to a longer length than in the RtTA1 wild type. The mutant strain was also more efficient in symbiotic performance. The functional interrelation between PssP2 and proteins encoded within the Pss-I region was further supported by data from bacterial two-hybrid assays providing evidence for PssP2 interactions with PssT polymerase, as well as glycosyltransferase PssC. A possible role for PssP2 in a complex involved in EPS chain-length determination is discussed.

  9. High throughput screening of particle conditioning operations: II. Evaluation of scale-up heuristics with prokaryotically expressed polysaccharide vaccines.

    Science.gov (United States)

    Noyes, Aaron; Huffman, Ben; Berrill, Alex; Merchant, Nick; Godavarti, Ranga; Titchener-Hooker, Nigel; Coffman, Jonathan; Sunasara, Khurram; Mukhopadhyay, Tarit

    2015-08-01

    Multivalent polysaccharide conjugate vaccines are typically comprised of several different polysaccharides produced with distinct and complex production processes. Particle conditioning steps, such as precipitation and flocculation, may be used to aid the recovery and purification of such microbial vaccine products. An ultra scale-down approach to purify vaccine polysaccharides at the micro-scale would greatly enhance productivity, robustness, and speed the development of novel conjugate vaccines. In part one of this series, we described a modular and high throughput approach to develop particle conditioning processes (HTPC) for biologicals that combines flocculation, solids removal, and streamlined analytics. In this second part of the series, we applied HTPC to industrially relevant feedstreams comprised of capsular polysaccharides (CPS) from several bacterial species. The scalability of HTPC was evaluated between 0.8 mL and 13 L scales, with several different scaling methodologies examined. Clarification, polysaccharide yield, impurity clearance, and product quality achieved with HTPC were reproducible and comparable with larger scales. Particle sizing was the response with greatest sensitivity to differences in processing scale and enabled the identification of useful scaling rules. Scaling with constant impeller tip speed or power per volume in the impeller swept zone offered the most accurate scale up, with evidence that time integration of these values provided the optimal basis for scaling. The capability to develop a process at the micro-scale combined with evidence-based scaling metrics provide a significant advance for purification process development of vaccine processes. The USD system offers similar opportunities for HTPC of proteins and other complex biological molecules. PMID:25727194

  10. Methods of saccharification of polysaccharides in plants

    Science.gov (United States)

    Howard, John; Fake, Gina

    2014-04-29

    Saccharification of polysaccharides of plants is provided, where release of fermentable sugars from cellulose is obtained by adding plant tissue composition. Production of glucose is obtained without the need to add additional .beta.-glucosidase. Adding plant tissue composition to a process using a cellulose degrading composition to degrade cellulose results in an increase in the production of fermentable sugars compared to a process in which plant tissue composition is not added. Using plant tissue composition in a process using a cellulose degrading enzyme composition to degrade cellulose results in decrease in the amount of cellulose degrading enzyme composition or exogenously applied cellulase required to produce fermentable sugars.

  11. INTERACTION OF IONIC LIQUIDS WITH POLYSACCHARIDES

    Directory of Open Access Journals (Sweden)

    Tim Liebert

    2008-05-01

    Full Text Available The use of ionic liquids (ILs in the field of cellulose chemistry opens up a broad variety of new opportunities. Besides the regeneration of the biopolymer to fibers, films, and beads, this new class of cellulose solvents is particularly useful for the homogeneous chemical modification of the polysaccharide. In this review, the potential of ILs as a reaction medium for the homogeneous cellulose functionalization is discussed. It is shown that numerous conversions proceed very efficiently and the ILs may be recycled. But it is also demonstrated that some side reactions have to be considered.

  12. Enzymatic synthesis of oligo- and polysaccharide fatty acid esters

    NARCIS (Netherlands)

    Broek, van den L.A.M.; Boeriu, C.G.

    2013-01-01

    Amphiphilic oligo- and polysaccharides (e.g. polysaccharide alkyl or alkyl-aryl esters) form a new class of polymers with exceptional properties. They function as polymeric surfactants, whilst maintaining most of the properties of the starting polymeric material such as emulsifying, gelling, and fil

  13. In vitro antioxidant activity of polysaccharide from Gardenia jasminoides ellis

    Science.gov (United States)

    Fan, Y.; Ge, Z.; Luo, A.

    2011-01-01

    A water-soluble polysaccharide, GP, was isolated from Gardenia jasminoides Ellis through hot water extraction followed by ethanol precipitation. The in vitro free radicals scavenging tests exhibited that GP has significant scavenging abilities especially for ABTS, DPPH, and hydroxyl radicals, which suggests that the polysaccharide GP is a novel antioxidant. ?? 2011 Academic Journals.

  14. Life cycle assessment of polysaccharide materials: a review

    NARCIS (Netherlands)

    Shen, L.; Patel, M.K.

    2008-01-01

    Apart from conventional uses of polysaccharide materials, such as food, clothing, paper packaging and construction, new polysaccharide products and materials have been developed. This paper reviews life cycle assessment (LCA) studies in order to gain insight of the environmental profiles of polysacc

  15. Characterisation of cell wall polysaccharides in bilberries and black currants

    NARCIS (Netherlands)

    Hilz, H.

    2007-01-01

    During berry juice production, polysaccharides are released from the cell walls and cause thickening and high viscosity when the berries are mashed. Consequences are a low juice yield and a poor colour. This can be prevented by the use of enzymes that degrade these polysaccharides. To use these enzy

  16. Tribological Properties of Neutral Polysaccharide Solutions under Simulated Oral Conditions

    NARCIS (Netherlands)

    Zinoviadou, K.; Janssen, A.M.; Jongh, de H.H.J.

    2008-01-01

    Predictability of the perception of foods thickened by polysaccharides is only poor. Therefore, the effect of saliva on the lubrication properties of 2 types of neutral polysaccharides, cross-linked starch and locust bean gum, was studied. Despite the similar bulk rheological behavior of the 2 polys

  17. Polysaccharides isolated from Acai fruit induce innate immune responses.

    Directory of Open Access Journals (Sweden)

    Jeff Holderness

    Full Text Available The Açaí (Acai fruit is a popular nutritional supplement that purportedly enhances immune system function. These anecdotal claims are supported by limited studies describing immune responses to the Acai polyphenol fraction. Previously, we characterized γδ T cell responses to both polyphenol and polysaccharide fractions from several plant-derived nutritional supplements. Similar polyphenol and polysaccharide fractions are found in Acai fruit. Thus, we hypothesized that one or both of these fractions could activate γδ T cells. Contrary to previous reports, we did not identify agonist activity in the polyphenol fraction; however, the Acai polysaccharide fraction induced robust γδ T cell stimulatory activity in human, mouse, and bovine PBMC cultures. To characterize the immune response to Acai polysaccharides, we fractionated the crude polysaccharide preparation and tested these fractions for activity in human PBMC cultures. The largest Acai polysaccharides were the most active in vitro as indicated by activation of myeloid and γδ T cells. When delivered in vivo, Acai polysaccharide induced myeloid cell recruitment and IL-12 production. These results define innate immune responses induced by the polysaccharide component of Acai and have implications for the treatment of asthma and infectious disease.

  18. Separation of Pneumcoccal Capsular Polysaccharide BY Gel Extraction

    Institute of Scientific and Technical Information of China (English)

    Xu Xiaoping; Huang Xinghua; Li Zhongqin; Chen Jiebo

    2004-01-01

    Separation of pneumcoccal capsular polysaccharide by gel was investigated in this paper. The gels used here were poly(acrylamide-co-sodium methacrylate)gels and prepared by free radical polymerization in aqueous solution. The experimental results indicated that gel extraction is a potential method to separate pneumcoccal capsular polysaccharide from its dilute solution.

  19. An improved haemolytic plaque assay for the detection of cells secreting antibody to bacterial antigens

    DEFF Research Database (Denmark)

    Barington, T; Heilmann, C

    1992-01-01

    Recent advances in the development of conjugate polysaccharide vaccines for human use have stimulated interest in the use of assays detecting antibody-secreting cells (AbSC) with specificity for bacterial antigens. Here we present improved haemolytic plaque-forming cell (PFC) assays detecting Ab......SC with specificity for tetanus and diphtheria toxoid as well as for Haemophilus influenzae type b and pneumococcal capsular polysaccharides. These assays were found to be less time consuming, more economical and yielded 1.9-3.4-fold higher plaque numbers than traditional Jerne-type PFC assays. In the case of anti...

  20. Modified polysaccharides as alternative binders for foundry industry

    Directory of Open Access Journals (Sweden)

    K. Kaczmarska

    2016-10-01

    Full Text Available Polysaccharides constitute a wide group of important polymers with many commercial applications, for example food packaging, fibres, coatings, adhesives etc. This review is devoted to the presentation of polysaccharide application in foundry industry. In this paper the selected properties of foundry moulding sand and core sand containing modified polysaccharides as binders are presented according to foreign literature data. Also, author’s own research about effect of using moulding sand binder consisting of modified polysaccharide (modified starch or its composition with non-toxic synthetic polymers are discussed. Based on technologies taken under consideration in this paper, it could be concluded that polysaccharides are suitable as an alternative for use as binder in foundry moulding applications.

  1. Structural Features and Healthy Properties of Polysaccharides Occurring in Mushrooms

    Directory of Open Access Journals (Sweden)

    Eva Guillamón

    2012-12-01

    Full Text Available Polysaccharides from mushrooms have attracted a great deal of attention due to the many healthy benefits they have demonstrated, such as immunomodulation, anticancer activity, prevention and treatment of cardiovascular diseases, antiviral and antimicrobial effects, among others. Isolation and purification of polysaccharides commonly involve several steps, and different techniques are actually available in order to increase extraction yield and purity. Studies have demonstrated that the molecular structure and arrangement significantly influence the biological activity; therefore, there is a wide range of analytical techniques for the elucidation of chemical structures. Different polysaccharides have been isolated from mushrooms, most of them consisting of β-linked glucans, such as lentinan from Lentinus edodes, pleuran from Pleurotus species, schizophyllan from Schizophyllum commune, calocyban from Calocybe indica, or ganoderan and ganopoly from Ganoderma lucidum. This article reviews the main methods of polysaccharide isolation and structural characterization, as well as some of the most important polysaccharides isolated from mushrooms and the healthy benefits they provide.

  2. Microanalysis of Plant Cell Wall Polysaccharides

    Institute of Scientific and Technical Information of China (English)

    Nicolai Obel; Veronika Erben; Tatjana Schwarz; Stefan Kühne; Andrea Fodor; Markus Pauly

    2009-01-01

    Oligosaccharide Mass Profiling (OLIMP) allows a fast and sensitive assessment of cell wall polymer structure when coupled with Matrix Assisted Laser Desorption Ionisation Time Of Flight Mass Spectrometry (MALDI-TOF MS). The short time required for sample preparation and analysis makes possible the study of a wide range of plant organs, revealing a high degree of heterogeneity in the substitution pattern of wall polymers such as the cross-linking glycan xyloglucan and the pectic polysaccharide homogalacturonan. The high sensitivity of MALDI-TOF allows the use of small amounts of samples, thus making it possible to investigate the wall structure of single cell types when material is collected by such methods as laser micro-dissection. As an example, the analysis of the xyloglucan structure in the leaf cell types outer epidermis layer, entire epidermis cell layer, palisade mesophyll cells, and vascular bundles were investigated. OLIMP is amenable to in situ wall analysis, where wall polymers are analyzed on unprepared plant tissue itself without first iso-lating cell walls. In addition, OLIMP enables analysis of wall polymers in Golgi-enriched fractions, the location of nascent matrix polysaccharide biosynthesis, enabling separation of the processes of wall biosynthesis versus post-deposition apo-plastic metabolism. These new tools will make possible a semi-quantitative analysis of the cell wall at an unprecedented level.

  3. EXTRACELLULAR POLYSACCHARIDES OF POTATO RING ROT PATHOGEN

    Directory of Open Access Journals (Sweden)

    Shafikova Т.N.

    2006-03-01

    Full Text Available Many bacteria, including phytopathogenic ones produce extracellular polysaccharides or exopolysaccharides which are universal molecules. Causal agent of potato ring rot, Clavibacter michiganensis subspecies sepedonicus, secretes exopolysaccharides which role in pathogenesis is poorly investigated. The aim of our research is to ascertain the composition and structure of Clavibacter michiganensis subspecies sepedonicus exopolysaccharides. Exopolysaccharides of Clavibacter michiganensis subspecies sepedonicus are determined to consist of 4-6 anionic and neutral components which have molecular weights from 700 kDa. Glucose is a major monomer of polysaccharides and arabinose, rhamnose and mannose are minor monomers. Glucose is present in α-Dglucopyranose and β-D-glucopyranose configurations. Calcium is determined to be a component of exopolysaccharides. Components of exopolysaccharides of potato ring rot pathogen are probably capableto associate via calcium ions and other ionic interactions that may result in a change of their physiological activity. Further studies of Clavibacter michiganensis subspecies sepedonicus exopolysaccharides composition and structure can serve a base for the synthesis of their chemical analogues with elicitor action.

  4. Primary structure and configuration of tea polysaccharide

    Institute of Scientific and Technical Information of China (English)

    2004-01-01

    The monosaccharide composition of a tea polysaccharide(TGC)was determined by GC-MS method.Furthermore,the primary structure of tea polysaccharide and its configuration in the aqueous solution were investigated utilizing a combination of classical chemical methods and modern instrumental techniques including GC-MS,Proton NMR,UV and CD.The results indicate that TGC consists of 6 monosaccharides: Rha,Ara,Xyl,Glu,Man and Gal.The configuration of TGC in water solution is proposed to be an ordered helix.The possible primary structure of TGC was outlined as below: the basic structure of the main chain consists of Rha,Glu and Gal units.All three monosaccharides can potentially be connected to branch chains consisting of mainly Ara,and the linkages could be in β1 →2,β1 →3,β2→3 forms.When branch chain is absent in the basic structure of the main chain the linkage consists of only β1→3; Xyl exists at the terminal end of either the main chain or the branch chain with β1 → linkage.

  5. A family of starch-active polysaccharide monooxygenases.

    Science.gov (United States)

    Vu, Van V; Beeson, William T; Span, Elise A; Farquhar, Erik R; Marletta, Michael A

    2014-09-23

    The recently discovered fungal and bacterial polysaccharide monooxygenases (PMOs) are capable of oxidatively cleaving chitin, cellulose, and hemicelluloses that contain β(1→4) linkages between glucose or substituted glucose units. They are also known collectively as lytic PMOs, or LPMOs, and individually as AA9 (formerly GH61), AA10 (formerly CBM33), and AA11 enzymes. PMOs share several conserved features, including a monocopper center coordinated by a bidentate N-terminal histidine residue and another histidine ligand. A bioinformatic analysis using these conserved features suggested several potential new PMO families in the fungus Neurospora crassa that are likely to be active on novel substrates. Herein, we report on NCU08746 that contains a C-terminal starch-binding domain and an N-terminal domain of previously unknown function. Biochemical studies showed that NCU08746 requires copper, oxygen, and a source of electrons to oxidize the C1 position of glycosidic bonds in starch substrates, but not in cellulose or chitin. Starch contains α(1→4) and α(1→6) linkages and exhibits higher order structures compared with chitin and cellulose. Cellobiose dehydrogenase, the biological redox partner of cellulose-active PMOs, can serve as the electron donor for NCU08746. NCU08746 contains one copper atom per protein molecule, which is likely coordinated by two histidine ligands as shown by X-ray absorption spectroscopy and sequence analysis. Results indicate that NCU08746 and homologs are starch-active PMOs, supporting the existence of a PMO superfamily with a much broader range of substrates. Starch-active PMOs provide an expanded perspective on studies of starch metabolism and may have potential in the food and starch-based biofuel industries.

  6. A mucoadhesive polymer extracted from tamarind seed improves the intraocular penetration and efficacy of rufloxacin in topical treatment of experimental bacterial keratitis.

    Science.gov (United States)

    Ghelardi, Emilia; Tavanti, Arianna; Davini, Paola; Celandroni, Francesco; Salvetti, Sara; Parisio, Eva; Boldrini, Enrico; Senesi, Sonia; Campa, Mario

    2004-09-01

    Bacterial keratitis is a serious infectious ocular disease requiring prompt treatment to prevent frequent and severe visual disabilities. Standard treatment of bacterial keratitis includes topical administration of concentrated antibiotic solutions repeated at frequent intervals in order to reach sufficiently high drug levels in the corneal tissue to inhibit bacterial growth. However, this regimen has been associated with toxicity to the corneal epithelium and requires patient hospitalization. In the present study, a mucoadhesive polymer extracted from tamarind seeds was used for ocular delivery of 0.3% rufloxacin in the treatment of experimental Pseudomonas aeruginosa and Staphylococcus aureus keratitis in rabbits. The polysaccharide significantly increased the intra-aqueous penetration of rufloxacin in both infected and uninfected eyes. Rufloxacin delivered by the polysaccharide reduced P. aeruginosa and S. aureus in the cornea at a higher rate than that obtained by rufloxacin alone. In particular, use of the polysaccharide allowed a substantial reduction of S. aureus in the cornea to be achieved even when the time interval between drug administrations was extended. These results suggest that the tamarind seed polysaccharide prolongs the precorneal residence times of antibiotics and enhances drug accumulation in the cornea, probably by reducing the washout of topically administered drugs. The tamarind seed polysaccharide appears to be a promising candidate as a vehicle for the topical treatment of bacterial keratitis.

  7. The immunostimulating role of lichen polysaccharides: a review.

    Science.gov (United States)

    Shrestha, Gajendra; St Clair, Larry L; O'Neill, Kim L

    2015-03-01

    The immune system has capacity to suppress the development or progression of various malignancies including cancer. Research on the immunomodulating properties of polysaccharides obtained from plants, microorganisms, marine organisms, and fungi is growing rapidly. Among the various potential sources, lichens, symbiotic systems involving a fungus and an alga and/or a cyanobacterium, show promise as a potential source of immunomodulating compounds. It is well known that lichens produce an abundance of structurally diverse polysaccharides. However, only a limited number of studies have explored the immunostimulating properties of lichen polysaccharides. Published studies have shown that some lichen polysaccharides enhance production of nitrous oxide (NO) by macrophages and also alter the production levels of various proinflammatory and antiinflammatory cytokines (IL-10, IL-12, IL-1β, TNF-α, and IFN-α/β) by macrophages and dendritic cells. Although there are only a limited number of studies examining the role of lichen polysaccharides, all results suggest that lichen polysaccharides can induce immunomodulatory responses in macrophages and dendritic cells. Thus, a detailed evaluation of immunomodulatory capacity of lichen polysaccharides could provide a unique opportunity for the discovery of novel therapeutic agents. PMID:25339289

  8. New polysaccharide-based polymer electrolytes; Nouveaux electrolytes polymeres a base de polysaccharides

    Energy Technology Data Exchange (ETDEWEB)

    Velasquez-Morales, P.; Le Nest, J.F.; Gandini, A. [Ecole Francaise de Papeterie et des Industries Graphique, 38 - Saint Martin d`Heres (France)

    1996-12-31

    Polysaccharides like cellulose and chitosan are known for their filmic properties. This paper concerns the synthesis and the study of chitosan-based polymer electrolytes. A preliminary work concerns the study of glucosamine reactivity. The poly-condensation of chitosan ethers (obtained by reaction with ethylene oxide or propylene oxide) with bifunctional and monofunctional oligo-ethers leads to the formation of thin lattices (10 {mu}m) having excellent mechanical properties. The presence of grafted polyether chains along the polysaccharide skeleton allows to modify the vitreous transition temperature and the molecular disorder of the system. Two type of polymer electrolytes have been synthesized: electrolytes carrying a dissolved alkaline metal salt and ionomers. The analysis of their thermal, dynamical mechanical, nuclear magnetic relaxation, electrical, and electrochemical properties shows that this new class of polymer electrolytes has the same performances as ethylene poly-oxide based amorphous lattices plus the advantage of having good filmic properties. Abstract only. (J.S.)

  9. Enzymatic method for improving the injectability of polysaccharides. [US Patent Application

    Science.gov (United States)

    Griffith, W.L.; Compere, A.L.; Holleman, J.W.

    A method for enhancing the ability of polysaccharides in aqueous solution to flow through a porous medium comprises contacting the polysaccharides with an endoenzyme capable of hydrolyzing at least one of the linkages of the sugar units of the polysaccharides and maintaining the polysaccharides in contact with the enzyme under hydrolysis conditions for a time sufficient to decrease the tendency of the polysaccharides to plug the porous medium yet insufficient to decrease the viscosity of the aqueous polysaccharides by more than 25%. The partially hydrolyzed polysaccharides are useful as thickening agents for flooding water used to recover oil from oil-containing subterranean formations.

  10. [The molecular-weight characteristics of the bacterial lectins and humus components in soil].

    Science.gov (United States)

    Votselko, S K; Iutinskaia, G A; Kovalenko, E A; Kucheriavaia, N S

    2000-01-01

    A method has been developed to determine the molecular-weight distribution of biologically active substances: bacterial lectins and soil humus compounds. The method based on the simultaneous centrifugation of samples and molecular weight standards in the density gradient of NaCl solutions or combined gradient of NaCl and CsCl solutions permits analysing biologically active substances: lectins, proteins, polysaccharides, protein-polysaccharide complexes, humus compounds in the interval of molecular weight of 13.7 kappa [symbol: see text] a to 2000 kappa [symbol: see text] a. The use of this method in the soil researches makes it possible to study the dynamics of change of molecular parameters of the soil organic matter depending on agrotechnical methods as well as to determine transformation regularities of microbial polysaccharides.

  11. A Direct Sulfation Process of a Marine Polysaccharide in Ionic Liquid

    Directory of Open Access Journals (Sweden)

    Nathalie Chopin

    2015-01-01

    Full Text Available GY785 is an exopolysaccharide produced by a mesophilic bacterial strain Alteromonas infernus discovered in the deep-sea hydrothermal vents. GY785 highly sulfated derivative (GY785 DRS was previously demonstrated to be a promising molecule driving the efficient mesenchymal stem cell chondrogenesis for cartilage repair. This glycosaminoglycan- (GAG- like compound was modified in a classical solvent (N,N′-dimethylformamide. However, the use of classical solvents limits the polysaccharide solubility and causes the backbone degradation. In the present study, a one-step efficient sulfation process devoid of side effects (e.g., polysaccharide depolymerization and/or degradation was developed to produce GAG-like derivatives. The sulfation of GY785 derivative (GY785 DR was carried out using ionic liquid as a reaction medium. The successful sulfation of this anionic and highly branched heteropolysaccharide performed in ionic liquid would facilitate the production of new molecules of high specificity for biological targets such as tissue engineering or regenerative medicine.

  12. Development of capsular polysaccharide-based glycoconjugates for immunization against melioidosis and glanders.

    Science.gov (United States)

    Burtnick, Mary N; Heiss, Christian; Roberts, Rosemary A; Schweizer, Herbert P; Azadi, Parastoo; Brett, Paul J

    2012-01-01

    Burkholderia pseudomallei and Burkholderia mallei, the etiologic agents of melioidosis and glanders, respectively, cause severe disease in humans and animals and are considered potential agents of biological warfare and terrorism. Diagnosis and treatment of infections caused by these pathogens can be challenging and, in the absence of chemotherapeutic intervention, acute disease is frequently fatal. At present, there are no human or veterinary vaccines available for immunization against these emerging/re-emerging infectious diseases. One of the long term objectives of our research, therefore, is to identify and characterize protective antigens expressed by B. pseudomallei and B. mallei and use them to develop efficacious vaccine candidates. Previous studies have demonstrated that the 6-deoxy-heptan capsular polysaccharide (CPS) expressed by these bacterial pathogens is both a virulence determinant and a protective antigen. Consequently, this carbohydrate moiety has become an important component of the various subunit vaccines that we are currently developing in our laboratory. In the present study, we describe a reliable method for isolating CPS antigens from O-polysaccharide (OPS) deficient strains of B. pseudomallei; including a derivative of the select agent excluded strain Bp82. Utilizing these purified CPS samples, we also describe a simple procedure for covalently linking these T-cell independent antigens to carrier proteins. In addition, we demonstrate that high titer IgG responses can be raised against the CPS component of such constructs. Collectively, these approaches provide a tangible starting point for the development of novel CPS-based glycoconjugates for immunization against melioidosis and glanders.

  13. Safety Evaluation of Turmeric Polysaccharide Extract: Assessment of Mutagenicity and Acute Oral Toxicity

    Directory of Open Access Journals (Sweden)

    Chandrasekaran Chinampudur Velusami

    2013-01-01

    Full Text Available Curcuma longa Linn. (Zingiberaceae commonly known as turmeric has long been used for centuries as a spice and household remedy. The present study was carried out to assess the possible mutagenic potential and acute oral toxicity of polysaccharide extract of turmeric rhizome (NR-INF-02 using standard tests. The standard battery of in vitro genotoxicity tests, bacterial reverse mutation test (BRMT, chromosome aberration (CA, and micronucleus (MN tests were employed to assess the possible mutagenic activity of NR-INF-02 (Turmacin. The results showed no mutagenic effect with NR-INF-02 up to a dose of 5000 µg/mL in BRMT. The results on CA and MN tests revealed the non clastogenic activity of NR-INF-02 in a dose range of 250.36 to 2500 µg/mL with and without metabolic activation (S9. In acute oral toxicity study, NR-INF-02 was found to be safe up to 5 g/kg body weight in Wistar rats. Overall, results indicated that polysaccharide extract of C. longa was found to be genotoxically safe and also exhibited maximum tolerable dose of more than 5 g/kg rat body weight.

  14. Composite polysaccharide fibers prepared by electrospinning and coating.

    Science.gov (United States)

    Maeda, N; Miao, J; Simmons, T J; Dordick, J S; Linhardt, R J

    2014-02-15

    Composite polysaccharide fibers composed two oppositely charged natural polysaccharides, chitosan and hyaluronic acid, were prepared by electrospinning and subsequent coating. The fiber size distribution was characterized by scanning electron microscopy. Chitosan/hyaluronic acid composite fibers were stable in water but showed controlled release of hyaluronic acid into phosphate buffered saline, and the presence of 3-wt% hyaluronic acid coating improved the swelling ratio to 30%. The resulting composite polysaccharide fibers have a number of potential biomedical applications in wound healing applications and in drug delivery systems. PMID:24507368

  15. Use of paramagnetic chelated metal derivatives of polysaccharides and spin-labeled polysaccharides as contrast agents in magnetic resonance imaging

    Energy Technology Data Exchange (ETDEWEB)

    Bligh, S.W.; Harding, C.T.; Sadler, P.J.; Bulman, R.A.; Bydder, G.M.; Pennock, J.M.; Kelly, J.D.; Latham, I.A.; Marriott, J.A. (Department of Chemistry, Birkbeck College, London (England))

    1991-02-01

    Soluble and insoluble polysaccharides were derivatized with diethylenetriaminepentaacetic acid (DTPA) and/or spin-labeled with 2,2,6,6-tetramethylpiperidine-1-oxyl (TEMPO). Polysaccharides derivatized with DTPA were prepared via cyanogen bromide activation, coupling to a diamine linker, and to DTPA anhydride. Spin-labeled polysaccharides were also prepared via cyanogen bromide activation. The extent of derivatization for dextran (18 kDa) was about 120 glucose units per DTPA, and for cellulose and starch about 15-30 units per DTPA. For spin-labeled polysaccharides, the average loading ranged from 1 nitroxide per 16 glucose units for starch to 181 for dextran (82 kDa). These derivatized paramagnetic polysaccharides were shown to be more effective relaxants than the small paramagnetic molecules alone. Both soluble and insoluble polysaccharide-linker-DTPA-Gd(3) complexes were effectively cleared from the body (rats) after oral administration. After intravenous administration, the biodistribution of dextran-linker-DTPA-Gd(3) complexes differed significantly from that of GdDTPA. Reduction of the nitroxide by ascorbic acid was retarded in the polysaccharide derivatives, particularly in starch derivatized with both nitroxide and linker-DTPA-Cu(2). These agents showed contrast enhancement in the gastrointestinal tract of rabbits.

  16. NMR studies of polysaccharides from brown seaweeds

    Energy Technology Data Exchange (ETDEWEB)

    Noseda, M.D.; Tisher, C.A.; Gorin, P.A.J.; Duarte, M.E.R. [Parana Univ., Curitiba, PR (Brazil). Dept. de Bioquimica; Cerezo, A.S. [Buenos Aires Univ. Nacional (Argentina). Dept. de Quimica Organica

    1997-12-31

    Alginic acid is the major intercellular polysaccharide serving as matrix in the brown algae and is comprised of an unbranched chain of (1->4)-linked {beta}-D-mannuronic acid (M) and {alpha}-L-guluronic acid (G), arranged in a blockwise fashion. The composition of the monomer residues and the block structure varies depending on the source of the polymer. The selective binding of cations to alginate accounts for its ability to form gels, which is dependent on the number and lenght of the G-blocks. They are widely used industrially for their ability to retain water, and for their gelling, viscosifying and stabilizing properties (Smidsrod and draget, 1996). In this study, alginate composition and block structure in Sargassum stenophyllum has been determined by chemical methods and NMR spectroscopic analysis. (author) 4 refs., 3 figs.

  17. Nutraceutical functionalities of polysaccharides from marine invertebrates.

    Science.gov (United States)

    Choi, Byeong-Dae; Choi, Yeung Joon

    2012-01-01

    Many researchers are seeking functional materials from marine resources. These marine resources can be used as traditional food additives, and specifically, these are based on polysaccharides. To date, there is a big opportunity to develop new high-value added products with indispensable functional characteristics, which can be used in nutraceuticals either as additives or supplements. Also, a crossover in the pharmaceutical market may be established. Some glycosaminoglycans (GAGs) mimetic-type molecules are already being utilized in the field of nutrition as well as in the cosmetics industry. This chemical is used as a dietary supplement to maintain the structure and function of cartilages, for the relief of pain caused by osteoarthritic joints, and can also be used as an anti-inflammatory agent. Recently, in relation to the prevalence of mad cow disease and avian influenza, the production of GAGs from marine invertebrates offers new market opportunities as compared with that obtained from bovine or avian livestock. PMID:22361178

  18. An Acidic Polysaccharide from Tribulus terrestris

    Institute of Scientific and Technical Information of China (English)

    HaiShengCHEN; WingNangLEUNG; 等

    2002-01-01

    An aqueous acidic polysaccharide, named rhamnogalacturonan (designated as TIP-D2) was isolated from Tribulus terrestris L by means of DEAE-cellulose chromatography and gel filtration. The molecular mass of TTP-D2 was estimated to be 26 KDa by gel filtration.TTP-D2 is composed of galacturonic acid, rhamnose, arabinose, galactose,fucose,mannose,xylose and glucose in a ratio of 71.4:13.5:5.6:4.9:3.1:1.9:1.9:1.0. The main chain structure of TTP-D2 was elucidated as an acidic hetero-polysaccaride with the connection of α-(1-4) galacturonic acid with α-(1-3) rhamnose by GC analysis of partially hydrolyzed products and determination of 1H,13C-NMR spectra.

  19. An Acidic Polysaccharide from Tribulus terrestris

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    An aqucous acidic polysaccharide, named rhamnogalacturonan (designated as TTP-D2)was isolated from Tribulus terrestris L by means of DEAE-cellulose chromatography and gel filtration. The molecular mass of TTP-D2 was estimated to be 26 KDa by gel filtration. TTP-D2 is composed of galacturonic acid, rhamnose, arabinose, galactose, fucose, mannosc, xylose and glucose in a ratio of 71.4: 13.5: 5.6: 4.9: 3.1: 1.9: 1.9: 1.0. The main chain structure of TTP-D2 was elucidated as an acidic hetero-polysaccharidc with the connection of α-(l-4) galacturonic acid with α-(1-3) rhamnose by GC analysis of partially hydrolyzed products and the determination of 1H, 13C-NMR spectra.

  20. Fermentation Characterization of Chinese Yam Polysaccharide and Its Effects on the Gut Microbiota of Rats

    Directory of Open Access Journals (Sweden)

    X. F. Kong

    2009-01-01

    Full Text Available Rat was used to characterize Chinese Yam polysaccharides (CYPs. In Exp. 1, maximum volume and rate of gas production in CYP 3-supplemented group were higher than other CYP-supplemented groups and control group, while pH values and NH3 contents in CYP 2-, CYP 3-, and CYP 4-supplemented groups were lower than control group. Contents of acetate, propionate and butyrate increased by supplementing CYP 3 or CYP 4 compared to other groups, except for glucose-supplemented group. Contents of isobutyrate for CYPs groups decreased compared to control group. CYP 3 enhanced beneficial gut microbiota, but suppressed bacterial pathogens. In Exp. 2, contents of acetate and butyrate in cecal digesta of rats fed 0.25 or 0.5 g/kg CYP 3 were higher than other groups on day 7. pH values in 0.25 and 0.5 g/kg groups were lower than 1.0 g/kg group. Contents of acetate in 0.25 and 0.5 g/kg groups were greater than other 2 groups on day 21. Gut microflora in CYP 3-supplemented rats had greater diversity than non-supplemented rats. CYP 3 enriched beneficial gut microbiota, but suppressed bacterial pathogens in rat cecum. These findings suggested that CYP 3 is a good source of carbon and energy, and may improve bacterial community diversity and modulate short-chain fatty acid production in hindgut of rats.

  1. Effect of dandelion polysaccharides on the retardation of the quality changes of white shrimp.

    Science.gov (United States)

    Wang, Hong-Bin

    2014-07-01

    Dandelion polysaccharides (DPs) have antibacterial and antioxidant activities. In this study, investigated were the effects of the DPs on preservation of white shrimp (Penaeus vannamei) during refrigerated storage. Shrimp samples were untreated or soaked in the DPs solution, and then they were stored under refrigerated conditions. Samples were taken periodically and evaluated for total viable count, pH value, total volatile basic nitrogen, and overall acceptability score. Treatment of the DPs effectively retarded bacterial growth and pH increasing, reduced total volatile basic nitrogen, and increased overall acceptability score of white shrimp (P. vannamei) during refrigerated storage. The results show that the DPs treatment could prolong shelf life for up to 10 days.

  2. Molecular mapping of the cell wall polysaccharides of the human pathogen Streptococcus agalactiae

    Science.gov (United States)

    Beaussart, Audrey; Péchoux, Christine; Trieu-Cuot, Patrick; Hols, Pascal; Mistou, Michel-Yves; Dufrêne, Yves F.

    2014-11-01

    The surface of many bacterial pathogens is covered with polysaccharides that play important roles in mediating pathogen-host interactions. In Streptococcus agalactiae, the capsular polysaccharide (CPS) is recognized as a major virulence factor while the group B carbohydrate (GBC) is crucial for peptidoglycan biosynthesis and cell division. Despite the important roles of CPS and GBC, there is little information available on the molecular organization of these glycopolymers on the cell surface. Here, we use atomic force microscopy (AFM) and transmission electron microscopy (TEM) to analyze the nanoscale distribution of CPS and GBC in wild-type (WT) and mutant strains of S. agalactiae. TEM analyses reveal that in WT bacteria, peptidoglycan is covered with a very thin (few nm) layer of GBC (the ``pellicle'') overlaid by a 15-45 nm thick layer of CPS (the ``capsule''). AFM-based single-molecule mapping with specific antibody probes shows that CPS is exposed on WT cells, while it is hardly detected on mutant cells impaired in CPS production (ΔcpsE mutant). By contrast, both TEM and AFM show that CPS is over-expressed in mutant cells altered in GBC expression (ΔgbcO mutant), indicating that the production of the two surface glycopolymers is coordinated in WT cells. In addition, AFM topographic imaging and molecular mapping with specific lectin probes demonstrate that removal of CPS (ΔcpsE), but not of GBC (ΔgbcO), leads to the exposure of peptidoglycan, organized into 25 nm wide bands running parallel to the septum. These results indicate that CPS forms a homogeneous barrier protecting the underlying peptidoglycan from environmental exposure, while the presence of GBC does not prevent peptidoglycan detection. This work shows that single-molecule AFM, combined with high-resolution TEM, represents a powerful platform for analysing the molecular arrangement of the cell wall polymers of bacterial pathogens.

  3. Chemical polyglycosylation and nanolitre detection enables single-molecule recapitulation of bacterial sugar export

    Science.gov (United States)

    Kong, Lingbing; Almond, Andrew; Bayley, Hagan; Davis, Benjamin G.

    2016-05-01

    The outermost protective layer of both Gram-positive and Gram-negative bacteria is composed of bacterial capsular polysaccharides. Insights into the interactions between the capsular polysaccharide and its transporter and the mechanism of sugar export would not only increase our understanding of this key process, but would also help in the design of novel therapeutics to block capsular polysaccharide export. Here, we report a nanolitre detection system that makes use of the bilayer interface between two droplets, and we use this system to study single-molecule recapitulation of sugar export. A synthetic strategy of polyglycosylation based on tetrasaccharide monomers enables ready synthetic access to extended fragments of K30 oligosaccharides and polysaccharides. Examination of the interactions between the Escherichia coli sugar transporter Wza and very small amounts of fragments of the K30 capsular polysaccharide substrate reveal the translocation of smaller but not larger fragments. We also observe capture events that occur only on the intracellular side of Wza, which would complement coordinated feeding by adjunct biosynthetic machinery.

  4. Impact of a pectic polysaccharide on oenin copigmentation mechanism.

    Science.gov (United States)

    Fernandes, Ana; Brás, Natércia F; Oliveira, Joana; Mateus, Nuno; de Freitas, Victor

    2016-10-15

    Copigmentation plays an important role in the colors provided by anthocyanins. However, little attention has been paid to the interaction between anthocyanins and cell wall compounds (e.g. polysaccharides) and the impact of this interaction on anthocyanins color, a fundamental issue to be considered in industrial applications of these pigments as food colorants. The copigmentation binding constants (KCP) for the interaction between malvidin-3-O-glucoside and (+)-catechin in the presence of low methoxylated pectic polysaccharide were determined. The values obtained showed that in the presence of pectic polysaccharide the copigmentation binding constants decreased. These results probably suggest the occurrence of competition equilibrium in which the presence of pectin limited the association between catechin and oenin. (1)H NMR studies revealed that the dissociation constant determined for these complexes was very similar in absence and presence of 1.5g/L pectin with this polysaccharide apparently not affecting the strength of anthocyanin-catechin binding. PMID:27173529

  5. Anti-diabetic polysaccharides from natural sources: A review.

    Science.gov (United States)

    Wang, Peng-Cheng; Zhao, Shan; Yang, Bing-You; Wang, Qiu-Hong; Kuang, Hai-Xue

    2016-09-01

    Diabetes mellitus (DM) is a metabolic disease attracted worldwide concerns, which severely impairs peoples' quality of life and is attributed to several life-threatening complications, including atherosclerosis, nephropathy and retinopathy. The current therapies for DM include mainly oral anti-diabetic drugs and insulin. However, continuous use of these causes insulin resistance and side-effects, and the demand of effective, nontoxic and affordable drugs for DM patients is eager. Several previous studies have shown that non-toxic biological macromolecules, mainly polysaccharides, possess prominent efficacies on DM. Based on these encouraging observations, a great deal of efforts have been focused on discovering anti-diabetic polysaccharides for the development of effective therapeutics for DM. This review focuses on the advancements in the anti-diabetic efficacy of various natural polysaccharides and polysaccharide complexes from 2010 to 2015. PMID:27185119

  6. Detection of Inulin, a Prebiotic Polysaccharide, in Maple Syrup.

    Science.gov (United States)

    Sun, Jiadong; Ma, Hang; Seeram, Navindra P; Rowley, David C

    2016-09-28

    Maple syrup is a widely consumed plant-derived natural sweetener produced by concentrating xylem sap collected from certain maple (Acer) species. During thermal evaporation of water, natural phytochemical components are concentrated in maple syrup. The polymeric components from maple syrup were isolated by ethanol precipitation, dialysis, and anion exchange chromatography and structurally characterized by glycosyl composition analysis, glycosyl linkage analysis, and nuclear magnetic resonance spectroscopy. Among the maple syrup polysaccharides, one neutral polysaccharide was characterized as inulin with a broad molecular weight distribution, representing the first isolation of this prebiotic carbohydrate from a xylem sap. In addition, two acidic polysaccharides with structural similarity were identified as arabinogalactans derived from rhamnogalacturonan type I pectic polysaccharides.

  7. Antioxidant activities of five polysaccharides from Inonotus obliquus.

    Science.gov (United States)

    Huang, Sheng-quan; Ding, Shaodong; Fan, Liuping

    2012-06-01

    Five polysaccharides (IOP1b, IOP2a, IOP2c, IOP3a and IOP4) were isolated and purified from Inonotus obliquus by DEAE-Sepharose fast flow and SepharoseCL-6B column chromatography. Their chemical and physical characteristics were determined and antioxidant activities were investigated on the basis of hydroxyl radical assay, superoxide radical assay and ferric-reducing antioxidant power assay. The results showed that five polysaccharides exhibited antioxidant activities, and the higher content of uronic acid and proteinous substances, the stronger antioxidant activities of polysaccharides. Besides, molecular weights of polysaccharides also influence their antioxidant activities. IOP3a and IOP4 showed higher antioxidant properties than IOP1b, IOP2a and IOP2c. PMID:22484729

  8. Radiation-chemical degradation of cellulose and other polysaccharides

    International Nuclear Information System (INIS)

    Results of studies on the radiation-chemical transformations of cellulose, its ethers, and some other polysaccharides (xylan, starch, dextran, chitin, chitosan, and heparin) are discussed. Ionising radiation causes the degradation of these compounds accompanied by decomposition of the pyranose ring and formation of compounds with carbonyl and carboxy groups, as well as formation of hydrogen, carbon dioxide, and carbon monoxide. The efficiency of degradation increases considerably with temperature and depends on the structure of the polysaccharide and the nature of its substituents. A mechanism of the radiation-chemical transformations of cellulose and other polysaccharides is suggested. The prospects of using radiation-chemical methods for processing of cellulose and other polysaccharides in industry and agriculture are considered. The bibliography includes 213 references.

  9. Synbiotic matrices derived from plant oligosaccharides and polysaccharides

    Science.gov (United States)

    A porous synbiotic matrix was prepared by lyophilization of alginate and pectin or fructan oligosaccharides and polysaccharides cross-linked with calcium. These synbiotic matrices were excellent physical structures to support the growth of Lactobacillus acidophilus (1426) and Lactobacillus reuteri (...

  10. Comparison of Polysaccharides from Two Species of Ganoderma

    Directory of Open Access Journals (Sweden)

    Yu-Ping Tang

    2012-01-01

    Full Text Available Ganoderma lucidum and Ganoderma sinense, known as Lingzhi in Chinese, are commonly used Chinese medicines with excellent beneficial health effects. Triterpenes and polysaccharides are usually considered as their main active components. However, the content of triterpenes differs significantly between the two species of Ganoderma. To date, a careful comparison of polysaccharides from the two species of Ganoderma has not been performed. In this study, polysaccharides from fruiting bodies of two species of Lingzhi collected from different regions of China were analyzed and compared based on HPSEC-ELSD and HPSEC-MALLS-RI analyses, as well as enzymatic digestion and HPTLC of acid hydrolysates. The results indicated that both the HPSEC-ELSD profiles and the molecular weights of the polysaccharides were similar. Enzymatic digestion showed that polyshaccharides from all samples of Lingzhi could be hydrolyzed by pectinase and dextranase. HPTLC profiles of their TFA hydrolysates colored with different reagents and their monosaccharides composition were also similar.

  11. Visualization of capsular polysaccharide induction in Acidithiobacillus ferrooxidans

    NARCIS (Netherlands)

    Bellenberg, S.; Leon Morales, C.F.; Sand, W.; Vera, M.

    2012-01-01

    Extracellular Polymeric Substances (EPS) are of fundamental importance for attachment to metal sulfides, biofilm formation and leaching efficiency of Acidithiobacillus ferrooxidans. In this work we have visualized the capsular polysaccharides (CPS) of A. ferrooxidans ATCC 23270 using the fluorescent

  12. Extraction and antioxidant activity of polysaccharides from Rana chensinensis skin.

    Science.gov (United States)

    Wang, Zhanyong; Zhao, Yuanyuan; Su, Tingting

    2015-01-22

    The extraction process of polysaccharides from Rana chensinensis skin was optimized by using a Box-Behnken design. The optimum extraction conditions were as follows: extraction time, 4.96h; extraction temperature, 100°C; ratio of water to raw material, 60; and extraction frequency, 1. Under these conditions, the experimental polysaccharide yield was 2.03±0.14%, which agreed with the predicted yield. The purified polysaccharide RCSP II was successfully obtained by diethylaminoethanol-Sepharose and Sepharose CL-6B column chromatography. In vitro experiments showed that RCSP II exhibited a strong scavenging activity against superoxide anion and 1,1-diphenyl-2-picrylhydrazyl radicals but a weak scavenging activity against hydroxyl radicals. RCSP II also showed a strong reducing capacity. Thus, this polysaccharide can be used as a natural antioxidant in functional foods or medicines.

  13. Identification, characterization and immunogenicity of an O-antigen capsular polysaccharide of Francisella tularensis.

    Directory of Open Access Journals (Sweden)

    Michael A Apicella

    Full Text Available Capsular polysaccharides are important factors in bacterial pathogenesis and have been the target of a number of successful vaccines. Francisella tularensis has been considered to express a capsular antigen but none has been isolated or characterized. We have developed a monoclonal antibody, 11B7, which recognizes the capsular polysaccharide of F. tularensis migrating on Western blot as a diffuse band between 100 kDa and 250 kDa. The capsule stains poorly on SDS-PAGE with silver stain but can be visualized using ProQ Emerald glycoprotein stain. The capsule appears to be highly conserved among strains of F. tularensis as antibody 11B7 bound to the capsule of 14 of 14 F. tularensis type A and B strains on Western blot. The capsular material can be isolated essentially free of LPS, is phenol and proteinase K resistant, ethanol precipitable and does not dissociate in sodium dodecyl sulfate. Immunoelectron microscopy with colloidal gold demonstrates 11B7 circumferentially staining the surface of F. tularensis which is typical of a polysaccharide capsule. Mass spectrometry, compositional analysis and NMR indicate that the capsule is composed of a polymer of the tetrasaccharide repeat, 4-alpha-D-GalNAcAN-(1->4-alpha-D-GalNAcAN-(1->3-beta-D-QuiNAc-(1->2-beta-D-Qui4NFm-(1-, which is identical to the previously described F. tularensis O-antigen subunit. This indicates that the F. tularensis capsule can be classified as an O-antigen capsular polysaccharide. Our studies indicate that F. tularensis O-antigen glycosyltransferase mutants do not make a capsule. An F. tularensis acyltransferase and an O-antigen polymerase mutant had no evidence of an O-antigen but expressed a capsular antigen. Passive immunization of BALB/c mice with 75 microg of 11B7 protected against a 150 fold lethal challenge of F. tularensis LVS. Active immunization of BALB/c mice with 10 microg of capsule showed a similar level of protection. These studies demonstrate that F. tularensis

  14. Impacts of hydrophilic colanic acid on bacterial attachment to microfiltration membranes and subsequent membrane biofouling.

    Science.gov (United States)

    Yoshida, Keitaro; Tashiro, Yosuke; May, Thithiwat; Okabe, Satoshi

    2015-06-01

    In order to examine the interactions between physicochemical properties of specific extracellular polymeric substances (EPS) and membrane biofouling, we investigated the impacts of hydrophilic colanic acid, as a model extracellular polysaccharide component, on initial bacterial attachment to different microfiltration (MF) membranes and membrane biofouling by using Escherichia coli strains producing different amounts of colanic acid. In a newly designed microtiter plate assay, the bacterial attachment by an E. coli strain RcsF(+), which produces massive amounts of colanic acid, decreased only to a hydrophobic membrane because the colanic acid made cell surfaces more hydrophilic, resulting in low cell attachment to hydrophobic membranes. The bench-scale cross-flow filtration tests followed by filtration resistance measurement revealed that RcsF(+) caused severe irreversible membrane fouling (i.e., pore-clogging), whereas less extracellular polysaccharide-producing strains caused moderate but reversible fouling to all membranes used in this study. Further cross-flow filtration tests indicated that colanic acid liberated in the bulk phase could rapidly penetrate pre-accumulated biomass layers (i.e., biofilms) and then directly clogged membrane pores. These results indicate that colanic acid, a hydrophilic extracellular polysaccharide, and possible polysaccharides with similar characteristics with colanic acid are considered as a major cause of severe irreversible membrane fouling (i.e., pore-clogging) regardless of biofilm formation (dynamic membrane).

  15. Composite polysaccharide fibers prepared by electrospinning and coating

    OpenAIRE

    Maeda, N; Miao, J; Simmons, T.J.; Dordick, J S; Linhardt, R.J.

    2013-01-01

    Composite polysaccharide fibers composed two oppositely charged natural polysaccharides, chitosan and hyaluronic acid, were prepared by electrospinning and subsequent coating The fiber size distribution was characterized by scanning electron microscopy. Chitosan/hyaluronic acid composite fibers were stable in water but showed controlled release of hyaluronic acid into phosphate buffered saline, and the presence of 3-wt% hyaluronic acid coating improved the swelling ratio to 30%. The resulting...

  16. Antioxidant properties of cell wall polysaccharides of Stevia rebaudiana leaves

    OpenAIRE

    Mediesse Kengne Francine; Woguia Alice Louise; Fogue Souopgui Pythagore; Atogho-Tiedeu Barbara; Simo Gustave; Thaddée Boudjeko

    2014-01-01

    Objective: To examine the total phenolic and protein contents, and the antioxidant activities of cell wall polysaccharide fractions of Stevia rebaudiana leaves. Methods: Three different polysaccharide-enriched fractions, namely FPE (extract with 50 mmol/ L ethylene diamine tetra acetic acid), FPK (extract with 0.05 mol/L KOH) and FH (extract with 4 mol/L KOH) were extracted from Stevia rebaudiana leaves. The antioxidant activity of these fractions was evaluated based on thei...

  17. Safety Assessment of Microbial Polysaccharide Gums as Used in Cosmetics.

    Science.gov (United States)

    Fiume, Monice M; Heldreth, Bart; Bergfeld, Wilma F; Belsito, Donald V; Hill, Ronald A; Klaassen, Curtis D; Liebler, Daniel C; Marks, James G; Shank, Ronald C; Slaga, Thomas J; Snyder, Paul W; Andersen, F Alan

    2016-07-01

    The Cosmetic Ingredient Review Expert Panel assessed the safety of 34 microbial polysaccharide gums for use in cosmetics, finding that these ingredients are safe in cosmetic formulations in the present practices of use and concentration. The microbial polysaccharide gums named in this report have a variety of reported functions in cosmetics, including emulsion stabilizer, film former, binder, viscosity-increasing agent, and skin-conditioning agent. The Panel reviewed available animal and clinical data in making its determination of safety. PMID:27383198

  18. Immunomodulatory Activity and Partial Characterisation of Polysaccharides from Momordica charantia

    OpenAIRE

    Yuan-Yuan Deng; Yang Yi; Li-Fang Zhang; Rui-Fen Zhang; Yan Zhang; Zhen-Cheng Wei; Xiao-Jun Tang; Ming-Wei Zhang

    2014-01-01

    Momordica charantia Linn. is used as an edible and medicinal vegetable in sub-tropical areas. Until now, studies on its composition and related activities have been confined to compounds of low molecular mass, and no data have been reported concerning the plant’s polysaccharides. In this work, a crude polysaccharide of M. charantia (MCP) fruit was isolated by hot water extraction and then purified using DEAE-52 cellulose anion-exchange chromatography to produce two main fractions MCP1 and M...

  19. Characterisation of cell wall polysaccharides in bilberries and black currants

    OpenAIRE

    Hilz, H

    2007-01-01

    During berry juice production, polysaccharides are released from the cell walls and cause thickening and high viscosity when the berries are mashed. Consequences are a low juice yield and a poor colour. This can be prevented by the use of enzymes that degrade these polysaccharides. To use these enzymes most efficiently, the structure and composition of the cell walls had to be known. This thesis describes a detailed composition of the cell walls of bilberries and black currants. The obtained ...

  20. Prevention of bacterial adhesion

    DEFF Research Database (Denmark)

    Klemm, Per; Vejborg, Rebecca Munk; Hancock, Viktoria

    2010-01-01

    Management of bacterial infections is becoming increasingly difficult due to the emergence and increasing prevalence of bacterial pathogens that are resistant to available antibiotics. Conventional antibiotics generally kill bacteria by interfering with vital cellular functions, an approach that ...

  1. Liposome-Based Delivery Systems in Plant Polysaccharides

    Directory of Open Access Journals (Sweden)

    Meiwan Chen

    2012-01-01

    Full Text Available Plant polysaccharides consist of many monosaccharide by α- or β-glycosidic bond which can be extracted by the water, alcohol, lipophile liquid from a variety of plants including Cordyceps sinensis, astragalus, and mushrooms. Recently, many evidences illustrate that natural plant polysaccharides possess various biological activities including strengthening immunity, lowering blood sugar, regulating lipid metabolism, antioxidation, antiaging, and antitumour. Plant polysaccharides have been widely used in the medical field due to their special features and low toxicity. As an important drug delivery system, liposomes can not only encapsulate small-molecule compound but also big-molecule drug; therefore, they present great promise for the application of plant polysaccharides with unique physical and chemical properties and make remarkable successes. This paper summarized the current progress in plant polysaccharides liposomes, gave an overview on their experiment design method, preparation, and formulation, characterization and quality control, as well as in vivo and in vitro studies. Moreover, the potential application of plant polysaccharides liposomes was prospected as well.

  2. Characterization of active polysaccharides of HemoHIM

    Energy Technology Data Exchange (ETDEWEB)

    Shin, Kwang Sun; Shin, Myeong Suk; Bae, Beom Seon; Hwang, Yong Cheol [Kyonggi University, Suwon (Korea, Republic of); Ryu, Kwang Won [Chungju University, Chungju (Korea, Republic of)

    2007-07-15

    In this study, we aimed to elucidate the detailed structure and active moiety of polysaccharide, one of the active constituents of immune and hematopoietic modulating activities of HemoHIM. We first isolated the polysaccharide fractions from the hot water extracts of the each ingredient herbs (A. gigas, P. janonica, C. officinale) of HemoHIM and their mixture. These polysaccharides were composed of neutral (85.32-92.73%) and acidic (4.25-7.88%) saccharides, proteins (0.16-4.02%), and polyphenols (2.09-5.37%). The hydrolytic analysis of polysaccharide fractions showed that they commonly showed higher arabinose, galactose, and galacturonic acid contents. These result suggested that these polysaccharides may have higher contents of rhamnogalacturonan among pectic substances and the main active moiety is composed of polysaccharides. The anion exchange chromatography of HemoHIM and each ingredient herb extract using DEAE-Sepharose FF (Cl- form) column resulted in 1 non-adsorption and 8 adsorption fractions. The analysis of immune activity (lymphocyte proliferation) on these fractions showed that the fractions obtained by higher salt concentration carried the higher activity, but all fractions showed considerable immune activity

  3. Marine derived polysaccharides for biomedical applications: chemical modification approaches.

    Science.gov (United States)

    d'Ayala, Giovanna Gomez; Malinconico, Mario; Laurienzo, Paola

    2008-09-03

    Polysaccharide-based biomaterials are an emerging class in several biomedical fields such as tissue regeneration, particularly for cartilage, drug delivery devices and gelentrapment systems for the immobilization of cells. Important properties of the polysaccharides include controllable biological activity, biodegradability, and their ability to form hydrogels. Most of the polysaccharides used derive from natural sources; particularly, alginate and chitin, two polysaccharides which have an extensive history of use in medicine, pharmacy and basic sciences, and can be easily extracted from marine plants (algae kelp) and crab shells, respectively. The recent rediscovery of poly-saccharidebased materials is also attributable to new synthetic routes for their chemical modification, with the aim of promoting new biological activities and/or to modify the final properties of the biomaterials for specific purposes. These synthetic strategies also involve the combination of polysaccharides with other polymers. A review of the more recent research in the field of chemical modification of alginate, chitin and its derivative chitosan is presented. Moreover, we report as case studies the results of our recent work concerning various different approaches and applications of polysaccharide-based biomaterials, such as the realization of novel composites based on calcium sulphate blended with alginate and with a chemically modified chitosan, the synthesis of novel alginate-poly(ethylene glycol) copolymers and the development of a family of materials based on alginate and acrylic polymers of potential interest as drug delivery systems.

  4. Marine Derived Polysaccharides for Biomedical Applications: Chemical Modification Approaches

    Directory of Open Access Journals (Sweden)

    Paola Laurienzo

    2008-09-01

    Full Text Available Polysaccharide-based biomaterials are an emerging class in several biomedical fields such as tissue regeneration, particularly for cartilage, drug delivery devices and gelentrapment systems for the immobilization of cells. Important properties of the polysaccharides include controllable biological activity, biodegradability, and their ability to form hydrogels. Most of the polysaccharides used derive from natural sources; particularly, alginate and chitin, two polysaccharides which have an extensive history of use in medicine, pharmacy and basic sciences, and can be easily extracted from marine plants (algae kelp and crab shells, respectively. The recent rediscovery of poly-saccharidebased materials is also attributable to new synthetic routes for their chemical modification, with the aim of promoting new biological activities and/or to modify the final properties of the biomaterials for specific purposes. These synthetic strategies also involve the combination of polysaccharides with other polymers. A review of the more recent research in the field of chemical modification of alginate, chitin and its derivative chitosan is presented. Moreover, we report as case studies the results of our recent work concerning various different approaches and applications of polysaccharide-based biomaterials, such as the realization of novel composites based on calcium sulphate blended with alginate and with a chemically modified chitosan, the synthesis of novel alginate-poly(ethylene glycol copolymers and the development of a family of materials based on alginate and acrylic polymers of potential interest as drug delivery systems.

  5. Antitussive activity of polysaccharides isolated from the Malian medicinal plants.

    Science.gov (United States)

    Sutovská, M; Franová, S; Priseznaková, L; Nosálová, G; Togola, A; Diallo, D; Paulsen, B S; Capek, P

    2009-04-01

    From the leaves of popular Malian medicinal plants Trichilia emetica (TE) and Opilia celtidifolia (OC), and fruits of Crossopteryx febrifuga (CF) water and water-ethanol soluble polysaccharide materials were isolated. The results of chemical analysis of the crude polysaccharides showed the dominance of the arabinogalactan ( approximately 54%) and the rhamnogalacturonan ( approximately 30%) in T. emetica leaves, the arabinogalactan ( approximately 60%), the rhamnogalacturonan ( approximately 14%) and the glucuronoxylan ( approximately 14%) in O. celtidifolia leaves, and pectic type of polysaccharides ( approximately 75%) with a lower content of the arabinogalactan ( approximately 17%) in C. febrifuga fruits. The plant polysaccharides showed various biological effects on the citric acid-induced cough reflex and reactivity of airways smooth muscle in vivo conditions. T. emetica and O. celtidifolia polysaccharides possessed significant cough-suppressive effect on chemically induced cough. Furthermore, values of specific airways resistance pointed on bronchodilatory property of polysaccharides isolated from O. celtidifolia. However, the crude extract from C. febrifuga in the same dose as T. emetica and O. celtidifolia did not influence the experimentally induced cough as well as reactivity of airways smooth muscle despite of the fact that the water-ethanol extract is recommended for cough therapy in Mali in the form of syrup. PMID:19150368

  6. Correlation Between Chain Architecture and Hydration Water Structure in Polysaccharides.

    Science.gov (United States)

    Grossutti, Michael; Dutcher, John R

    2016-03-14

    The physical properties of confined water can differ dramatically from those of bulk water. Hydration water associated with polysaccharides provides a particularly interesting example of confined water, because differences in polysaccharide structure provide different spatially confined environments for water sorption. We have used attenuated total reflection infrared (ATR-IR) spectroscopy to investigate the structure of hydration water in films of three different polysaccharides under controlled relative humidity (RH) conditions. We compare the results obtained for films of highly branched, dendrimer-like phytoglycogen nanoparticles to those obtained for two unbranched polysaccharides, hyaluronic acid (HA), and chitosan. We find similarities between the water structuring in the two linear polysaccharides and significant differences for phytoglycogen. In particular, the results suggest that the high degree of branching in phytoglycogen leads to a much more well-ordered water structure (low density, high connectivity network water), indicating the strong influence of chain architecture on the structuring of water. These measurements provide unique insight into the relationship between the structure and hydration of polysaccharides, which is important for understanding and exploiting these sustainable nanomaterials in a wide range of applications.

  7. Oral versus postingestive origin of polysaccharide appetite in the rat.

    Science.gov (United States)

    Sclafani, A; Nissenbaum, J W

    1987-01-01

    Previous studies have revealed that rats consume substantial amounts of polysaccharide solutions, even if the solutions are made bitter with the addition of sucrose octa acetate (SOA). The present experiment used the gastric sham-feeding preparation to determine if it is the orosensory or postingestive properties of polysaccharides that motivate rats to consume polysaccharide (Polycose) solutions. In Experiment 1, food deprived rats sham fed less of a 0.05% SOA + 32% Polycose solution than they did of a 32% glucose solution, but their SOA-Polycose intake was still considerable (44 ml/hr). The same rats refused to sham feed SOA-gum and SOA-sugar solutions that were similar to the SOA-Polycose solution in bitter taste, viscosity and free sugar content. In Experiment 2, rats sham fed as much of a 32% Polycose solution as they did of a 32% sucrose solution. Despite the gastric fistula, some of the ingested Polycose was absorbed as evidenced by an increase in the rats' blood glucose levels. The addition of acarbose, a drug that inhibits polysaccharide digestion, to the Polycose solution blocked the increase in blood glucose, but did not reduce the rats' sham feeding of the solution. These findings indicate that it is the orosensory (presumably taste) properties of polysaccharide solutions, not their postingestive effects, that initially attract rats to the solutions. The results question the assumption that polysaccharides are "tasteless" to animals.

  8. Correlation Between Chain Architecture and Hydration Water Structure in Polysaccharides.

    Science.gov (United States)

    Grossutti, Michael; Dutcher, John R

    2016-03-14

    The physical properties of confined water can differ dramatically from those of bulk water. Hydration water associated with polysaccharides provides a particularly interesting example of confined water, because differences in polysaccharide structure provide different spatially confined environments for water sorption. We have used attenuated total reflection infrared (ATR-IR) spectroscopy to investigate the structure of hydration water in films of three different polysaccharides under controlled relative humidity (RH) conditions. We compare the results obtained for films of highly branched, dendrimer-like phytoglycogen nanoparticles to those obtained for two unbranched polysaccharides, hyaluronic acid (HA), and chitosan. We find similarities between the water structuring in the two linear polysaccharides and significant differences for phytoglycogen. In particular, the results suggest that the high degree of branching in phytoglycogen leads to a much more well-ordered water structure (low density, high connectivity network water), indicating the strong influence of chain architecture on the structuring of water. These measurements provide unique insight into the relationship between the structure and hydration of polysaccharides, which is important for understanding and exploiting these sustainable nanomaterials in a wide range of applications. PMID:26859153

  9. Phosphorylation of psyllium seed polysaccharide and its characterization.

    Science.gov (United States)

    Rao, Monica R P; Warrier, Deepa U; Gaikwad, Snehal R; Shevate, Prachi M

    2016-04-01

    Psyllium is widely used as a medicinally active natural polysaccharide for treating conditions like constipation, diarrhea, and irritable bowel syndrome, inflammatory bowel disease, ulcerative colitis and colon cancer. Studies have been performed to characterize and modify the polysaccharide obtained from psyllium seed husk and to evaluate its use as a pharmaceutical excipient, but no studies have been performed to evaluate the properties of the polysaccharide present in psyllium seeds. The present study focuses on phosphorylation of psyllium seed polysaccharide (PPS) using sodium tri-meta phosphate as the cross-linking agent. The modified phosphorylated psyllium seed polysaccharide was then evaluated for physicochemical properties, rheological properties, spectral analysis, thermal analysis, crosslinking density and acute oral toxicity studies. The modified polysaccharide (PhPPS) has a high swelling index due to which it can be categorized as a hydrogel. The percent increase in swelling of PhPPS as compared to PPS was found to be 90.26%. The PPS & PhPPS mucilages of all strengths were found to have shear thinning properties. These findings are suggestive of the potential use of PhPPS as gelling & suspending agent. PhPPS was found to have a mucoadhesive property which was comparable with carbopol. PMID:26769088

  10. Dynamics of water solutions of natural polysaccharides by fast field cycling nmr relaxometry

    Science.gov (United States)

    Prusova, Alena; Conte, Pellegrino; Kucerik, Jiri; de Pasquale, Claudio; Alonzo, Giuseppe

    2010-05-01

    Cryobiology studies the effect of low temperatures on living systems such as microorganisms and plants. In particular, plants growing in cold or frozen environments can survive such extreme conditions due to the cold hardening process. Hardening is a three step process during which, first, translocation of polysaccharides to the plant roots affects water structure in the cell-soil surface. For this reason, increase of cell-membrane permeability and resistance to temperatures from -5°C to -10°C is achieved. In a second step, chemical alteration of cell membrane arises and resistance to temperatures up to -20°C is obtained. The last hardening step consists in the vitrification of the plant tissues which allow plants to survive at temperatures as low as -50°C. Since polysaccharides play a very important role in the initial part of the cold hardening process, it is of paramount importance to study the effect of such natural biopolymers on water structure. Here, we present preliminary data obtained by fast field cycling NMR relaxometry on the effect of hyaluronan (an anionic, non-sulfated glycosaminoglycan) on water structure at different concentrations of the polysaccharide. Although hyaluronan is a polysaccharide found exceptionally in animal, human or bacterial bodies, in the present work it was used as a model "pilot" compound. In fact, it has an unique ability to hold water and it contains both polysaccharide and protein-like acetamido functionalities. For this reason, hyaluronan promotes the future research on other plant biopolymers such as, for instance, starch and other very specific proteins. Results revealed that different water-structure systems surround the molecule of hyaluronan in diluted and semidiluted systems. Namely, at the lowest hyaluronan concentration, three hydration shells can be recognized. The first hydration shell is made by bound water (BW) which is strongly fixed to the hyaluronan surface mainly through electrostatic interactions. A

  11. Polysaccharides from Agaricus bisporus and Agaricus brasiliensis show similarities in their structures and their immunomodulatory effects on human monocytic THP-1 cells

    Directory of Open Access Journals (Sweden)

    Wichers Harry J

    2011-07-01

    Full Text Available Abstract Background Mushroom polysaccharides have traditionally been used for the prevention and treatment of a multitude of disorders like infectious illnesses, cancers and various autoimmune diseases. Crude mushroom extracts have been tested without detailed chemical analyses of its polysaccharide content. For the present study we decided to chemically determine the carbohydrate composition of semi-purified extracts from 2 closely related and well known basidiomycete species, i.e. Agaricus bisporus and A. brasiliensis and to study their effects on the innate immune system, in particular on the in vitro induction of pro-inflammatory cytokines, using THP-1 cells. Methods Mushroom polysaccharide extracts were prepared by hot water extraction and precipitation with ethanol. Their composition was analyzed by GC-MS and NMR spectroscopy. PMA activated THP-1 cells were treated with the extracts under different conditions and the production of pro-inflammatory cytokines was evaluated by qPCR. Results Semi-purified polysaccharide extracts of A. bisporus and A. brasiliensis (= blazei were found to contain (1→6,(1→4-linked α-glucan, (1→6-linked β-glucan, and mannogalactan. Their proportions were determined by integration of 1H-NMR signs, and were considerably different for the two species. A. brasiliensis showed a higher content of β-glucan, while A. bisporus presented mannogalactan as its main polysaccharide. The extracts induced a comparable increase of transcription of the pro-inflammatory cytokine genes IL-1β and TNF-α as well as of COX-2 in PMA differentiated THP-1 cells. Pro-inflammatory effects of bacterial LPS in this assay could be reduced significantly by the simultaneous addition of A. brasiliensis extract. Conclusions The polysaccharide preparations from the closely related species A. bisporus and A. brasiliensis show major differences in composition: A. bisporus shows high mannogalactan content whereas A. brasiliensis has mostly

  12. Identification and functional characterization of the putative polysaccharide biosynthesis protein (CapD) of Enterococcus faecium U0317.

    Science.gov (United States)

    Ali, Liaqat; Spiess, Meike; Wobser, Dominique; Rodriguez, Marta; Blum, Hubert E; Sakιnç, Türkân

    2016-01-01

    Most bacterial species produce capsular polysaccharides that contribute to disease pathogenesis through evasion of the host innate immune system and are also involved in inhibiting leukocyte killing. In the present study, we identified a gene in Enterococcus faecium U0317 with homologies to the polysaccharide biosynthesis protein CapD that is made up of 336 amino acids and putatively catalyzes N-linked glycosylation. A capD deletion mutant was constructed and complemented by homologous recombination that was confirmed by PCR and sequencing. The mutant revealed different growth behavior and morphological changes compared to wild-type by scanning electron microscopy, also the capD mutant showed a strong hydrophobicity and that was reversed in the reconstituted mutant. For further characterization and functional analyses, in-vitro cell culture and in-vivo a mouse infection models were used. Antibodies directed against alpha lipotechoic acid (αLTA) and the peptidyl-prolyl cis-trans isomerase (αPpiC), effectively mediated the opsonophagocytic killing in the capD knock-out mutant, while this activity was not observed in the wild-type and reconstituted mutant. By comparison more than 2-fold decrease was seen in mutant colonization and adherence to both T24 and Caco2 cells. However, a significant higher bacterial colonization was observed in capD mutant during bacteremia in the animal model, while virulence in a mouse UTI (urinary tract infection) model, there were no obvious differences. Further studies are needed to elucidate the function of capsular polysaccharide synthesis gene clusters and its involvement in the disease pathogenesis with the aim to develop targeted therapies to treat multidrug-resistant E. faecium infections.

  13. Withania somnifera attenuates acid production, acid tolerance and extra-cellular polysaccharide formation of Streptococcus mutans biofilms.

    Science.gov (United States)

    Pandit, Santosh; Song, Kwang-Yeob; Jeon, Jae-Gyu

    2014-01-01

    Withania somnifera (Ashwagandha) is a plant of the Solanaceae family. It has been widely used as a remedy for a variety of ailments in India and Nepal. The plant has also been used as a controlling agent for dental diseases. The aim of the present study was to evaluate the activity of the methanol extract of W. somnifera against the physiological ability of cariogenic biofilms and to identify the components of the extract. To determine the activity of the extract, assays for sucrose-dependent bacterial adherence, glycolytic acid production, acid tolerance, and extracellular polysaccharide formation were performed using Streptococcus mutans biofilms. The viability change of S. mutans biofilms cells was also determined. A phytochemical analysis of the extract was performed using TLC and LC/MS/MS. The extract showed inhibitory effects on sucrose-dependent bacterial adherence (≥ 100 μg/ml), glycolytic acid production (≥ 300 μg/ml), acid tolerance (≥ 300 μg/ml), and extracellular polysaccharide formation (≥ 300 μg/ml) of S. mutans biofilms. However, the extract did not alter the viability of S. mutans biofilms cells in all concentrations tested. Based on the phytochemical analysis, the activity of the extract may be related to the presence of alkaloids, anthrones, coumarines, anthraquinones, terpenoids, flavonoids, and steroid lactones (withanolide A, withaferin A, withanolide B, withanoside IV, and 12-deoxy withastramonolide). These data indicate that W. somnifera may be a potential agent for restraining the physiological ability of cariogenic biofilms.

  14. f{sub 1}(1285) decays into a{sub 0}(980)π{sup 0}, f{sub 0}(980)π{sup 0} and isospin breaking

    Energy Technology Data Exchange (ETDEWEB)

    Aceti, F.; Oset, E. [Centro Mixto Universidad de Valencia-CSIC, Institutos de Investigacion de Paterna, Departamento de Fisica Teorica, Universidad de Valencia y IFIC, Valencia (Spain); Dias, J.M. [Centro Mixto Universidad de Valencia-CSIC, Institutos de Investigacion de Paterna, Departamento de Fisica Teorica, Universidad de Valencia y IFIC, Valencia (Spain); Universidade de Sao Paulo, Instituto de Fisica, Sao Paulo (Brazil)

    2015-04-01

    We evaluate the decay width for the processes f{sub 1}(1285) → π{sup 0} a{sub 0}(980) and f{sub 1}(1285) → π{sup 0} f{sub 1}(980)taking into account that all three resonances are dynamically generated from the meson-meson interaction, the f{sub 1}(1285) from K{sup *} anti K - c.c. and the a{sub 0}(980), f{sub 0}(980) from πη, K anti K and ππ, K anti K, respectively. We use a triangular mechanism similar to that of η(1405) → ππη, which provides a decay width for f{sub 1}(1285) → π{sup 0} a{sub 0}(980) with a branching fraction of the order of 30%, in agreement with experiment. At the same time we evaluate the decay width for the isospin-forbidden f{sub 1}(1285) → π{sup 0} f{sub 0}(980), which appears when we consider different masses for the charged and neutral kaons, and show that it is much more suppressed than in the η(1405) → ππη case, but gives rise to a narrow shape of the π{sup +}π{sup -} distribution similar to the one found in the η(1405) → ππη decay. (orig.)

  15. The polysaccharide from Tamarindus indica (TS-polysaccharide) protects cultured corneal-derived cells (SIRC cells) from ultraviolet rays.

    Science.gov (United States)

    Raimondi, L; Lodovici, M; Guglielmi, F; Banchelli, G; Ciuffi, M; Boldrini, E; Pirisino, R

    2003-03-01

    The aim of this work was to investigate the possible protective effect of a new viscosising agent, TS-polysaccharide, on corneal-derived cells (SIRC) exposed to ultraviolet-B rays. To verify this, SIRC cells were first exposed, in the absence or in the presence of TS-polysaccharide (1% w/v), for 9 s at the UV-B source and then post-incubated for 45 min at 37 degrees C. After this period the hydrogen peroxide (H(2)O(2)) accumulated in the medium and the concentration of 8-hydroxy-2'-deoxy-guanosine (8-OHdG) in cell DNA was measured. In addition, the amount of (3)H-methyl-thymidine incorporated in cellular DNA was evaluated after 18 h from irradiation. Our results show that cells exposed to UV-B rays accumulate H(2)O(2), and have higher levels of 8OHdG and a lower amount of (3)H-methyl-thymidine incorporated in DNA than control cells. In the presence of TS-polysaccharide, the H(2)O(2) and 8-OHdG accumulation, and the (3)H-methyl-thymidine incorporation were significantly reduced with respect to the values measured in cells exposed in the absence of the polysaccharide. We propose a protective role of the polysaccharide in reducing UV-B derived DNA damage to eye cells. This finding could be of some clinical importance when the polysaccharide is used as a delivery system for ophthalmic preparations.

  16. Surface Proteins of Streptococcus agalactiae and Related Proteins in Other Bacterial Pathogens.

    OpenAIRE

    Lindahl, Gunnar; Stålhammar-Carlemalm, Margaretha; Areschoug, Thomas

    2005-01-01

    Streptococcus agalactiae (group B Streptococcus) is the major cause of invasive bacterial disease, including meningitis, in the neonatal period. Although prophylactic measures have contributed to a substantial reduction in the number of infections, development of a vaccine remains an important goal. While much work in this field has focused on the S. agalactiae polysaccharide capsule, which is an important virulence factor that elicits protective immunity, surface proteins have received incre...

  17. Prevention of bacterial adhesion

    DEFF Research Database (Denmark)

    Klemm, Per; Vejborg, Rebecca Munk; Hancock, Viktoria

    2010-01-01

    that imposes selection pressure for resistant bacteria. New approaches are urgently needed. Targeting bacterial virulence functions directly is an attractive alternative. An obvious target is bacterial adhesion. Bacterial adhesion to surfaces is the first step in colonization, invasion, and biofilm formation....... As such, adhesion represents the Achilles heel of crucial pathogenic functions. It follows that interference with adhesion can reduce bacterial virulence. Here, we illustrate this important topic with examples of techniques being developed that can inhibit bacterial adhesion. Some of these will become...

  18. Immunomodulatory Polysaccharide from Chlorophytum borivilianum Roots

    Directory of Open Access Journals (Sweden)

    Mayank Thakur

    2011-01-01

    Full Text Available Chlorophytum borivilianum Santapau & Fernandes (Liliaceae is an ayurvedic Rasayana herb with immunostimulating properties. The polysaccharide fraction (CBP derived from hot water extraction of C. borivilianum (CB, comprising of ~31% inulin-type fructans and ~25% acetylated mannans (of hot water-soluble extract, was evaluated for its effect on natural killer (NK cell activity (in vitro. Human peripheral blood mononuclear cells (PBMCs, isolated from whole blood on a Ficoll-Hypaque density gradient, were tested in the presence or absence of varying concentrations of each C. borivilianum fraction for modulation of NK cell cytotoxic activity toward K562 cells. Preliminary cytotoxicity evaluation against P388 cells was performed to establish non-cytotoxic concentrations of the different fractions. Testing showed the observed significant stimulation of NK cell activity to be due to the CBP of C. borivilianum. Furthermore, in vivo evaluation carried out on Wistar strain albino rats for humoral response to sheep red blood cells (SRBCs and immunoglobulin-level determination using enzyme-linked immunosorbent assay (ELISA, exhibited an effectiveness of C. borivilianum aqueous extract in improving immune function. Present results provide useful information for understanding the role of CBP in modulating immune function.

  19. Antioxidant properties of cell wall polysaccharides of Stevia rebaudiana leaves

    Directory of Open Access Journals (Sweden)

    Mediesse Kengne Francine

    2014-12-01

    Full Text Available Objective: To examine the total phenolic and protein contents, and the antioxidant activities of cell wall polysaccharide fractions of Stevia rebaudiana leaves. Methods: Three different polysaccharide-enriched fractions, namely FPE (extract with 50 mmol/ L ethylene diamine tetra acetic acid, FPK (extract with 0.05 mol/L KOH and FH (extract with 4 mol/L KOH were extracted from Stevia rebaudiana leaves. The antioxidant activity of these fractions was evaluated based on their ability to scavenge DPPH (1, 1-diphenyl-2-picryl hydrazyl free radical, to reduce ferric power, to chelate ferrous ion and to protect human DNA. Results: The results indicated that protein content was found to be higher in FPK polysaccharide enriched fraction (47.48 µg per mg of FPK. Furthermore, the phenolic compound analysis according to the Folin-Ciocalteu method was higher in FPK (17.71 µg ferulic acid. The DPPH maximal inhibition percentage of the three polysaccharide-enriched fractions at 400 µg/mL was 27.66%, 59.90% and 23.21% respectively for FPE, FPK and FH. All the polysaccharide fractions exhibited a ferric reducing power except the FH one. The three fractions also exhibited lipid peroxidation inhibition, and they completely reverted the DNA damage induced by H2O2/FeCl2. FPK showed the strongest scavenging activity against the DPPH radical, the best chelating ability and lipid peroxidation inhibition. Conclusions: Stevia cell wall polysaccharide fractions are potent protective agents against oxidative stress. The analysis revealed major differences in the antioxidant activity in the three polysaccharides fractions. However, the 0.05 mol/L KOH pectin fraction (FPK showed better antioxidant activity.

  20. Antioxidant properties of cell wall polysaccharides of Stevia rebaudiana leaves

    Institute of Scientific and Technical Information of China (English)

    Mediesse Kengne Francine; Woguia Alice Louise; Fogue Souopgui Pythagore; Atogho-Tiedeu Barbara; Simo Gustave; Thadde Boudjeko

    2014-01-01

    Objective: To examine the total phenolic and protein contents, and the antioxidant activities of cell wall polysaccharide fractions of Stevia rebaudiana leaves.Methods:L ethylene diamine tetra acetic acid), FPK (extract with 0.05 mol/L KOH) and FH (extract with 4 mol/L KOH) were extracted from Stevia rebaudiana leaves. The antioxidant activity of these fractions was evaluated based on their ability to scavenge DPPH (1, 1-diphenyl-2-picryl hydrazyl) free radical, to reduce ferric power, to chelate ferrous ion and to protect human DNA. Three different polysaccharide-enriched fractions, namely FPE (extract with 50 mmol/Results: The results indicated that protein content was found to be higher in FPK polysaccharide enriched fraction (47.48 µg per mg of FPK). Furthermore, the phenolic compound analysis according to the Folin-Ciocalteu method was higher in FPK (17.71 µg ferulic acid). The DPPH maximal inhibition percentage of the three polysaccharide-enriched fractions at 400 µg/mL was 27.66%, 59.90% and 23.21% respectively for FPE, FPK and FH. All the polysaccharide fractions exhibited a ferric reducing power except the FH one. The three fractions also exhibited lipid peroxidation inhibition, and they completely reverted the DNA damage induced by H2O2/FeCl2. FPK showed the strongest scavenging activity against the DPPH radical, the best chelating ability and lipid peroxidation inhibition.Conclusions: Stevia cell wall polysaccharide fractions are potent protective agents against oxidative stress. The analysis revealed major differences in the antioxidant activity in the three polysaccharides fractions. However, the 0.05 mol/L KOH pectin fraction (FPK) showed better antioxidant activity.

  1. Relationship of proton motive force and the F(0)F (1)-ATPase with bio-hydrogen production activity of Rhodobacter sphaeroides: effects of diphenylene iodonium, hydrogenase inhibitor, and its solvent dimethylsulphoxide.

    Science.gov (United States)

    Hakobyan, Lilit; Gabrielyan, Lilit; Trchounian, Armen

    2012-08-01

    Rhodobacter sphaeroides MDC 6521 was able to produce bio-hydrogen (H(2)) in anaerobic conditions under illumination. In this study the effects of the hydrogenase inhibitor-diphenylene iodonium (Ph(2)I) and its solvent dimethylsulphoxide (DMSO) on growth characteristics and H(2) production by R. sphaeroides were investigated. The results point out the concentration dependent DMSO effect: in the presence of 10 mM DMSO H(2) yield was ~6 fold lower than that of the control. The bacterium was unable to produce H(2) in the presence of Ph(2)I. In order to examine the mediatory role of proton motive force (∆p) or the F(0)F(1)-ATPase in H(2) production by R. sphaeroides, the effects of Ph(2)I and DMSO on ∆p and its components (membrane potential (∆ψ) and transmembrane pH gradient), and ATPase activity were determined. In these conditions ∆ψ was of -98 mV and the reversed ∆pH was +30 mV, resulting in ∆p of -68 mV. Ph(2)I decreased ∆ψ in concentrations of 20 μM and higher; lower concentrations of Ph(2)I as DMSO had no valuable effect on ∆ψ. The R. sphaeroides membrane vesicles demonstrated significant ATPase activity sensitive to N,N'-dicyclohexylcarbodiimide. The 10-20 μM Ph(2)I did not affect the ATPase activity, whereas 40 μM Ph(2)I caused a marked inhibition (~2 fold) in ATPase activity. The obtained results provide novel evidence on the involvement of hydrogenase and the F(0)F(1)-ATPase in H(2) production by R. sphaeroides. Moreover, these data indicate the role of hydrogenase and the F(0)F(1)-ATPase in ∆p generation. In addition, DMSO might increase an interaction of nitrogenase with CO(2), decreasing nitrogenase activity and affecting H(2) production.

  2. Influence of divalent cations and pH adsorption of a bacterial polysaccharide adhesin

    Digital Repository Service at National Institute of Oceanography (India)

    Bhosle, N.B.; Suci, P.A.; Baty, A.M.; Weiner, R.M.; Geesey, G.G.

    exhibits a relatively large affinity for (Ge), or more precisely for the Ge oxide surface film. In its natural habitat MHS-3 attaches to marine sediments. This suggests that molecular properties of fr2ps have evolved to render it adhesive toward mineral...

  3. Bacterial capsular polysaccharide prevents the onset of asthma through T-cell activation

    OpenAIRE

    Johnson, Jenny L.; Jones, Mark B.; Cobb, Brian A.

    2014-01-01

    Over the last four decades, increases in the incidence of immune-mediated diseases in the Western world have been linked to changes in microbial exposure. It is becoming increasingly clear that the normal microbiota in the gut can profoundly alter susceptibility to a wide range of diseases, such as asthma, in which immune homeostasis is disrupted, yet the mechanisms governing this microbial influence remains poorly defined. In this study, we show that gastrointestinal exposure to PSA, a capsu...

  4. Hot-compressed water extraction of polysaccharides from soy hulls.

    Science.gov (United States)

    Liu, Hua-Min; Wang, Fei-Yun; Liu, Yu-Lan

    2016-07-01

    The polysaccharides of soy hulls were extracted by hot-compressed water at temperatures of 110 from 180°C and various treatment times (10-150min) in a batch system. It was determined that a moderate temperature and short time are suitable for the preparation of polysaccharides. The structure of xylan and the inter- and intra-chain hydrogen bonding of cellulose fibrils in the soy hulls were not significantly broken down. The polysaccharides obtained were primarily composed of α-L-arabinofuranosyl units, 4-O-methyl-glucuronic acid units and α-D-galactose units attached with substituted units. A sugar analysis indicated that arabinose was the major component, constituting 35.6-46.9% of the polysaccharide products extracted at 130°C, 140°C, and 150°C. This investigation contributes to the knowledge of the polysaccharides of soy by-products, which can reduce the environmental impact of waste from the food industries. PMID:26920272

  5. The Application of Polysaccharide Biocomposites to Repair Cartilage Defects

    Directory of Open Access Journals (Sweden)

    Feng Zhao

    2014-01-01

    Full Text Available Owing to own nature of articular cartilage, it almost has no self-healing ability once damaged. Despite lots of restore technologies having been raised in the past decades, no repair technology has smoothly substituted for damaged cartilage using regenerated cartilage tissue. The approach of tissue engineering opens a door to successfully repairing articular cartilage defects. For instance, grafting of isolated chondrocytes has huge clinical potential for restoration of cartilage tissue and cure of chondral injury. In this paper, SD rats are used as subjects in the experiments, and they are classified into three groups: natural repair (group A, hyaluronic acid repair (group B, and polysaccharide biocomposites repair (hyaluronic acid hydrogel containing chondrocytes, group C. Through the observation of effects of repairing articular cartilage defects, we concluded that cartilage repair effect of polysaccharide biocomposites was the best at every time point, and then the second best was hyaluronic acid repair; both of them were better than natural repair. Polysaccharide biocomposites have good biodegradability and high histocompatibility and promote chondrocytes survival, reproduction, and spliting. Moreover, polysaccharide biocomposites could not only provide the porous network structure but also carry chondrocytes. Consequently hyaluronic acid-based polysaccharide biocomposites are considered to be an ideal biological material for repairing articular cartilage.

  6. Isolation, Purification and Bioactivities of Polysaccharides from Irpex lacteus

    Institute of Scientific and Technical Information of China (English)

    ZHANG Na; LIU Yan; LU Jia-hui; WANG Juan; YANG Shuang; ZHANG Nan; MENG Qing-fan; TENG Li-rong

    2012-01-01

    Irpex lacteus has been widely used for treating chronic glomerulonephritis as a traditional Chinese medicine.Seven water-soluble polysaccharide fractions(ILN Ⅰ,ILN Ⅱ,ILN Ⅲ,ILA Ⅰ,ILA Ⅱ,ILB Ⅰ and ILB Ⅱ)were isolated and purified from Irpex lacteus by hot-water extraction,deproteinization,decolorization,dicthy laminoethyl(DEAE)-cellulose ion exchange and sephadex G100 chromatographies,respectively.The average molecular weights and monosaccharide composition of these polysaccharide fractions greatly differed from each other.The antitumor and antinephritis activities of the seven polysaccharide fractions were evaluated.It was found that ILN Ⅲ displayed significant inhibition effects on both humar hepatocellular liver carcinoma(HepG2)and hentietta lacks(HeLa)tumor cells with IC50 values of 60.95 and 99.95 μg/mL,respectively.ILA Ⅰ exhibited significant inhibition effects on murine mesangial cells(HBZT-1)with an IC50 value of 185.06 μg/mL.The inhibition effects of other polysaccharide fractions on these three cells were significantly different.These results suggest that the polysaccharide fractions isolated from Irpex lacteus have potential antitumor and antinephritis activities.

  7. Marine Polysaccharide Networks and Diatoms at the Nanometric Scale

    Directory of Open Access Journals (Sweden)

    Tea Mišić Radić

    2013-10-01

    Full Text Available Despite many advances in research on photosynthetic carbon fixation in marine diatoms, the biophysical and biochemical mechanisms of extracellular polysaccharide production remain significant challenges to be resolved at the molecular scale in order to proceed toward an understanding of their functions at the cellular level, as well as their interactions and fate in the ocean. This review covers studies of diatom extracellular polysaccharides using atomic force microscopy (AFM imaging and the quantification of physical forces. Following a brief summary of the basic principle of the AFM experiment and the first AFM studies of diatom extracellular polymeric substance (EPS, we focus on the detection of supramolecular structures in polysaccharide systems produced by marine diatoms. Extracellular polysaccharide fibrils, attached to the diatom cell wall or released into the surrounding seawater, form distinct supramolecular assemblies best described as gel networks. AFM makes characterization of the diatom polysaccharide networks at the micro and nanometric scales and a clear distinction between the self-assembly and self-organization of these complex systems in marine environments possible.

  8. ISOLATION AND CHARACTERIZATION OF SOLUBLE POLYSACCHARIDES FROM CALAMAGROSTIS ANGUSTIFOLIA KOM

    Directory of Open Access Journals (Sweden)

    Xue-Fei Cao

    2011-06-01

    Full Text Available Sequential treatments of dewaxed Calamagrostis angustifolia Kom with water (60 ºC and 90 ºC, 70% ethanol, and 70% ethanol containing 0.2%, 1.0%, 2.0%, 4.0%, and 8.0% NaOH at a solid to liquid ratio of 1:25 (g/mL at 80 ºC for 3 h yielded 36.2% soluble polysaccharides of the dry dewaxed material. The eight polysaccharide fractions obtained were comparatively studied by sugar analysis, GPC, FT-IR, 1H and 13C-NMR, and 2D-NMR (HSQC spectroscopy. The results showed that the water-soluble polysaccharides might contain noticeable amounts of β-D-glucan, as well as some pectic substances and galactoarabinoxylan. 70% ethanol-soluble polysaccharide was mainly arabinogalactan. The five alkali-soluble hemicelluloses were mainly galactoarabinoxylans. The Ara/Xyl and Ara/Gal values of H5-H8 fractions decreased with the increment of NaOH concentration from 1.0% to 8.0%. Meanwhile, the molecular weights had a declining trend from ~60,000 to ~40,000 g/mol. The smaller sized and more branched polysaccharides tended to be extracted in the early stages under milder conditions, and the larger molecular sized and more linear hemicelluloses tended to be isolated under more highly alkaline conditions.

  9. Superabsorbent polysaccharide hydrogels based on pullulan derivate as antibacterial release wound dressing.

    Science.gov (United States)

    Li, Huanan; Yang, Jing; Hu, Xiaona; Liang, Jie; Fan, Yujiang; Zhang, Xingdong

    2011-07-01

    To accomplish ideal wound dressing, hydrogels based on a natural polysaccharide, pullulan were synthesized by chemical cross-linking. The tensile strengths of the hydrogel films (1 mm thick) were determined to range from 0.663 to 1.097 MPa in proportion to cross-linking degrees and water contents. The swelling study of the hydrogels in water showed remarkable water absorption property with swelling ratio up to 4000%, which provided the hydrogel with quick hemostatic ability and prevent the wound bed from accumulation of exudates. The water vapor transmission rate and water retention of the hydrogels were found to be in the range of 2213-3498 g/m²/day and 34.74-45.81% (after 6 days), indicating that the hydrogel can maintain a moist environment over wound bed, which could prevent the dehydration of the wound bed and prevent the scab formation. Biocompatibility test revealed that the hydrogels were not cytotoxic. The hydrogel could load antimicrobial agents and effectively suppress bacterial proliferation to protect the wound from bacterial invasion. These results suggest that the pullulan hydrogels prepared in this study may have high potential as new ideal wound-dressing materials.

  10. Measurements of time-dependent CP violation in $B^0 \\to \\omega K_S^0$, $f_0(980) K_S^0$, $K_S^0 \\pi^0$ and $K^+ K^- K_S^0$ decays

    CERN Document Server

    Abe, K; Aihara, H; Anipko, D; Aoki, K; Arakawa, T; Arinstein, K; Asano, Y; Aso, T; Aulchenko, V M; Aushev, T; Aziz, T; Bahinipati, S; Bakich, A M; Balagura, V; Ban, Y; Banerjee, S; Barberio, E; Barbero, M; Bay, A; Bedny, I; Belous, K S; Bitenc, U; Bizjak, I; Blyth, S; Bondar, A; Bozek, A; Bracko, M; Brodzicka, J; Browder, T E; Chang, M C; Chang, P; Chao, Y; Chen, A; Chen, K F; Chen, W T; Cheon, B G; Chistov, R; Choi, J H; Choi, S K; Choi, Y; Choi, Y K; Chuvikov, A; Cole, S; Dalseno, J; Danilov, M; Dash, M; Dowd, R; Dragic, J; Drutskoy, A; Eidelman, S; Enari, Y; Epifanov, D A; Fratina, S; Fujii, H; Fujikawa, M; Gabyshev, N; Garmash, A; Gershon, T; Go, A; Gokhroo, G; Goldenzweig, P; Golob, B; Gorisek, A; Grosse-Perdekamp, M; Guler, H; Ha, H; Haba, J; Hara, K; Hara, T; Hasegawa, Y; Hastings, N C; Hayasaka, K; Hayashii, H; Hazumi, M; Heffernan, D; Higuchi, T; Hinz, L; Hokuue, T; Hoshi, Y; Hoshina, K; Hou, S; Hou, W S; Hsiung, Y B; Igarashi, Y; Iijima, T; Ikado, K; Imoto, A; Inami, K; Ishikawa, A; Ishino, H; Itoh, K; Itoh, R; Iwabuchi, M; Iwasaki, M; Iwasaki, Y; Jacoby, C; Jones, M; Kakuno, H; Kang, J H; Kang, J S; Kapusta, P; Kataoka, S U; Katayama, N; Kawai, H; Kawasaki, T; Khan, H R; Kibayashi, A; Kichimi, H; Kikuchi, N; Kim, H J; Kim, H O; Kim, J H; Kim, S K; Kim, T H; Kim, Y J; Kinoshita, K; Kishimoto, N; Korpar, S; Kozakai, Y; Krizan, P; Krokovnyi, P P; Kubota, T; Kulasiri, R; Kumar, R; Kuo, C C; Kurihara, E; Kusaka, A; Kuzmin, A; Kwon, Y J; Lange, J S; Leder, G; Lee, J; Lee, S E; Lee, Y J; Lesiak, T; Li, J; Limosani, A; Lin, C Y; Lin, S W; Liu, Y; Liventsev, D; MacNaughton, J; Majumder, G; Mandl, F; Marlow, D; Matsumoto, T; Matyja, A; McOnie, S; Medvedeva, T; Mikami, Y; Mitaroff, W A; Miyabayashi, K; Miyake, H; Miyata, H; Miyazaki, Y; Mizuk, R; Mohapatra, D; Moloney, G R; Mori, T; Müller, J; Murakami, A; Nagamine, T; Nagasaka, Y; Nakagawa, T; Nakahama, Y; Nakamura, I; Nakano, E; Nakao, M; Nakazawa, H; Natkaniec, Z; Neichi, K; Nishida, S; Nishimura, K; Nitoh, O; Noguchi, S; Nozaki, T; Ogawa, A; Ogawa, S; Ohshima, T; Okabe, T; Okuno, S; Olsen, S L; Ono, S; Ostrowicz, W; Ozaki, H; Pakhlov, P; Pakhlova, G; Palka, H; Park, C W; Park, H; Park, K S; Parslow, N; Peak, L S; Pernicka, M; Pestotnik, R; Peters, M; Piilonen, L E; Poluektov, A; Ronga, F J; Root, N; Rorie, J; Rózanska, M; Sahoo, H; Saitoh, S; Sakai, Y; Sakamoto, H; Sakaue, H; Sarangi, T R; Sato, N; Satoyama, N; Sayeed, K; Schietinger, T; Schneider, O; Schonmeier, P; Schümann, J; Schwanda, C; Schwartz, A J; Seidl, R; Seki, T; Senyo, K; Sevior, M E; Shapkin, M; Shen, Y T; Shibuya, H; Shwartz, B; Sidorov, V; Singh, J B; Sokolov, A; Somov, A; Soni, N; Stamen, R; Stanic, S; Staric, M; Stöck, H; Sugiyama, A; Sumisawa, K; Sumiyoshi, T; Suzuki, S; Suzuki, S Y; Tajima, O; Takada, N; Takasaki, F; Tamai, K; Tamura, N; Tanabe, K; Tanaka, M; Taylor, G N; Teramoto, Y; Tian, X C; Tikhomirov, I; Trabelsi, K; Tsai, Y T; Tse, Y F; Tsuboyama, T; Tsukamoto, T; Uchida, K; Uchida, Y; Uehara, S; Uglov, T; Ueno, K; Unno, Y; Uno, S; Urquijo, P; Ushiroda, Y; Usov, Yu; Varner, G; Varvell, K E; Villa, S; Wang, C C; Wang, C H; Wang, M Z; Watanabe, M; Watanabe, Y; Wicht, J; Widhalm, L; Wiechczynski, J; Won, E; Wu, C H; Xie, Q L; Yabsley, B D; Yamaguchi, A; Yamamoto, H; Yamamoto, S; Yamashita, Y; Yamauchi, M; Heyoung Yang; Yoshino, S; Yuan, Y; Yusa, Y; Zang, S L; Zhang, C C; Zhang, J; Zhang, L M; Zhang, Z P; Zhilich, V; Ziegler, T; Zupanc, A; Zürcher, D

    2006-01-01

    We present measurements of time-dependent CP asymmetries in $B^0 \\to \\omega K_S^0$, $f_0 (980) K_S^0$, $K_S^0 \\pi^0$ and $K^+ K^- K_S^0$ based on a sample of 535 $\\times 10^6$ $B\\bar{B}$ pairs collected at the $\\Upsilon(4S)$ resonance with the Belle detector at the KEKB energy-asymmetric $e^+ e^-$ collider. One neutral $B$ meson is fully reconstructed in one of the specified decay channels, and the flavor of the accompanying $B$ meson is identified from its decay products. CP-violation parameters for each of the decay modes are obtained from the asymmetries in the distributions of the proper-time intervals between the two B decays.

  11. Light-driven oxidation of polysaccharides by photosynthetic pigments and a metalloenzyme

    DEFF Research Database (Denmark)

    Cannella, David; Möllers, K. Benedikt; Frigaard, Niels-Ulrik;

    2016-01-01

    Oxidative processes are essential for the degradation of plant biomass. A class of powerful and widely distributed oxidative enzymes, the lytic polysaccharide monooxygenases (LPMOs), oxidize the most recalcitrant polysaccharides and require extracellular electron donors. Here we investigated...

  12. Hypoglycemic effect of Ganoderma lucidum polysaccharides

    Institute of Scientific and Technical Information of China (English)

    Hui-na ZHANG; Zhi-bin LIN

    2004-01-01

    AIM: To investigate the hypoglycemic effect of Ganoderma lucidum polysaccharides (Gl-PS) in the normal fasted mice and its possible mechanism. METHODS: Normal fasted mice were given a single dose of Gl-PS 25, 50, and 100 mg/kg by ip and the serum glucose was measured at 0, 3, and 6 h after administration. Gl-PS 1 00 mg/kg were also given by ip and the serum glucose and insulin levels were measured at 0 min, 30 min, 1 h, 3 h, 6 h, and 12 h.Pancreatic islets were isolated and incubated with glucose 5.6 mmol/L and different concentration of Gl-PS, the insulin content of islets and insulin release were examined. The islets fluorescent intensity of [Ca2+]i was also studied with a confocal microscope. Verapamil and egtazic acid were used to testify whether the insulin-releasing effect of Gl-PS was mediated by its ability to raise the Ca2+ influx. RESULTS: Gl-PS dose-dependently lowered the serum glucose levels at 3 h and 6 h after administration. Gl-PS 100 mg/kg raised the circulating insulin levels at 1 h after administration. In vitro, Gl-PS had no effect on islets insulin content, but it stimulated the insulin release after incubation with glucose 5.6 mmol/L. Confocal microscope showed that Gl-PS 100 mg/L had the capacity to raise the [Ca2+] i. The insulin-releasing effect of Gl-PS was inhibited by verapamil/egtazic acid. CONCLUSION:Gl-PS possesses the hypoglycemic effect on normal mice; one mechanism is through its insulin-releasing activity due to a facilitation of Ca2+ inflow to the pancreatic β cells.

  13. Structures of two cell wall-associated polysaccharides of a Streptococcus mitis biovar 1 strain. A unique teichoic acid-like polysaccharide and the group O antigen which is a C-polysaccharide in common with pneumococci

    DEFF Research Database (Denmark)

    Bergström, N; Jansson, P.-E.; Kilian, Mogens;

    2000-01-01

    be partially separated by gel chromatography. The structures of the two polysaccharides were determined by chemical methods and by NMR spectroscopy. The teichoic acid-like polymer has a heptasaccharide phosphate repeating unit with the following structure: The structure neither contains ribitol nor glycerol......The cell wall of Streptococcus mitis biovar 1 strain SK137 contains the C-polysaccharide known as the common antigen of a closely related species Streptococcus pneumoniae, and a teichoic acid-like polysaccharide with a unique structure. The two polysaccharides are different entities and could...... phosphate as classical teichoic acids do, thus we have used the expression teichoic acid-like for this polysaccharide. The following structure of the C-polysaccharide repeating unit was established: where AAT is 2-acetamido-4-amino-2,4, 6-trideoxy-D-galactose. It has a carbohydrate backbone identical...

  14. Partial Chemical Characterization of Immunomodulatory Polysaccharides from Plantago palmata Hook. f. s. Leaves

    OpenAIRE

    Gabriel Biringanine; Moustapha Ouedraogo; Bernard Vray; Anne Berit Samuelsen; Pierre Duez

    2012-01-01

    A previous work on Plantago palmata polysaccharides (PS) attributed immunomodulatory properties of leaves to a polysaccharide fraction (PS50) that stimulated NO and TNF-α production by interferon gamma- (IFN-γ-) activated macrophages. The present work aims to elucidate the chemical structure of these immunomodulatory polysaccharides. Size exclusion chromatography showed that the active polymers present an active fraction with a very high molecular weight (about 1200 kDa). These polysaccharide...

  15. Application of gamma irradiation for the enhanced physiological properties of polysaccharides from seaweeds

    Energy Technology Data Exchange (ETDEWEB)

    Choi, Jong-il; Kim, Hyun-Joo; Kim, Jae-Hun; Byun, Myung-Woo [Advanced Radiation Technology Institute, Korea Atomic Energy Research Institute, Jeongeup 580185 (Korea, Republic of); Soo Chun, Byeong; Hyun Ahn, Dong [Department of Food Science and Biotechnology, Pukyong National University, Busan 608737 (Korea, Republic of); Hwang, Young-Jeong [Division of Food Science, Jinju International University, Jinju 660759 (Korea, Republic of); Kim, Duk-Jin [Division of Food Engineering and Nutrition, Daegu University, Daegu 712714 (Korea, Republic of); Kim, Gwang Hoon [Department of Biology, Kongju National University, Chungnam 314701 (Korea, Republic of); Lee, Ju-Woon [Advanced Radiation Technology Institute, Korea Atomic Energy Research Institute, Jeongeup 580185 (Korea, Republic of)], E-mail: sjwlee@kaeri.re.kr

    2009-07-15

    Polysaccharides from seaweeds, fucoidan and laminarin, were irradiated with gamma rays, and their structural changes and anti-oxidative activities were investigated. The gamma irradiation decreased the average molecular weights of polysaccharides, and UV spectra of irradiated polysaccharides showed increases in the numbers of carboxyl and carbonyl groups and double bonds. DPPH radical scavenging ability and reducing power of the gamma irradiated polysaccharides were significantly higher than those non-irradiated.

  16. Nanocoating of titanium implant surfaces with organic molecules. Polysaccharides including glycosaminoglycans

    DEFF Research Database (Denmark)

    Gurzawska, Katarzyna; Svava, Rikke; Jørgensen, Niklas Rye;

    2012-01-01

    with focus on polysaccharides including glycosaminoglycans, and how these molecules change surface properties, cell reactions and affect on osseointegartion. The included in vitro studies demonstrated increased cell adhesion, proliferation and mineralization of a number of the tested polysaccharide...... nanocoatings. The included in vivo studies, showed improvement of bone interface reactions measured as increased Bone-to-Implant Contact length and Bone Mineral Density adjacent to the polysaccharide coated surfaces. Based on existing literature, surface modification with polysaccharide and glycosaminoglycans...

  17. [Comparison on polysaccharide content and PMP-HPLC fingerprints of polysaccharide in stems and leaves of Dendrobium officinale].

    Science.gov (United States)

    Zhou, Gui-Fen; Pang, Min-Xia; Chen, Su-Hong; Lv, Gui-Yuan; Yan, Mei-Qiu

    2014-03-01

    In order to provide scientific basics for exploitation and sufficient application of Dendrobium officinale leaves resources, the phenol-sulfuric acid method was applied to determine the polysaccharide content. The monosaccharides were derivated by PMP and the derivatives were identified by HPLC-DAD-ESI-MS(n) and the contents of mannose and glucose were determined simultaneously. Similarity evaluation system for chromatographic fingerprint of traditional Chinese medicine (2004A) was employed to generate the mean chromatogram and similarity analysis of the samples was carried out. The results demonstrated that polysaccharide content, monosaccharide compositions and composition ratio had an obvious difference between stems and leaves. The polysaccharide content of stems was higher than that of leaves. Monosaccharide composition in leaf was significantly different from that in stem. The polysaccharide from stems was composed of mannose and glucose, however the polysaccharide of leaves was acid heteropolysaccharide and was mainly composed of five monosaccharides, including mannose, galacturonic acid, glucose, galactose and arabinose. The similarity value of the 14 batches was above 0.9, indicating that similarity of fingerprints among different samples was high. The study can provide evidence for expanding the medicinal parts of D. officinale.

  18. Polysaccharides of higher fungi: Biological role, structure, and antioxidative activity

    Directory of Open Access Journals (Sweden)

    Kozarski Maja S.

    2014-01-01

    Full Text Available Fungal polysaccharides attract a lot of attention due to their multiple challenging biological properties, such as: anti-tumor, anti-viral, anticomplementary, anticoagulant, hypolipidemic and immunomodulatory and immune-stimulatory activities, which all together make them suitable for application in many quite distinctive areas, such as food industry, biomedicine, cosmetology, agriculture, environmental protection and waste water management. This article presents results with respect to biological properties, structure and procedures related to the isolation and activation of polysaccharides of higher fungi. It is considered and presented along with a review of the critical antioxidative activity and possible influence of the structural composition of polysaccharide extracts (isolated from these higher fungi upon their antioxidative properties.

  19. [Discussion on polysaccharide determination methods in new Chinese drug research].

    Science.gov (United States)

    Li, Ji-Ping

    2014-09-01

    According to existing problems in polysaccharide determination methods in new Chinese drug applications, the method suitability, chemical reference selection, components interference and method research were introduced. The author suggests that suitable determination method should be selected according to the structure and property of the polysaccharide, and validated. Some influent factors should be examined to assure the accuracy of the method, such as the stability and using amount of the visualizing reagent, visualizing time, maximum detection wavelength etc. Monosaccharide and other water soluble components should be removed from polysaccharide sample, and suitable reference substance and detection wavelength should be selected. It should pay attention to mutual interference of neutral and acidic saccharide, and use inhibitor to eliminate the interference. Because the slopes of the standard curves are different for different monosaccharide, it is proposed that the types and ratios of the monosaccharide in heteroglycan should be understood, and mixed reference substance solution in the ratio is prepared for determination. PMID:25522636

  20. Bioactivity and Applications of Sulphated Polysaccharides from Marine Microalgae

    Directory of Open Access Journals (Sweden)

    Rui Manuel Santos Costa de Morais

    2013-01-01

    Full Text Available Marine microalgae have been used for a long time as food for humans, such as Arthrospira (formerly, Spirulina, and for animals in aquaculture. The biomass of these microalgae and the compounds they produce have been shown to possess several biological applications with numerous health benefits. The present review puts up-to-date the research on the biological activities and applications of polysaccharides, active biocompounds synthesized by marine unicellular algae, which are, most of the times, released into the surrounding medium (exo- or extracellular polysaccharides, EPS. It goes through the most studied activities of sulphated polysaccharides (sPS or their derivatives, but also highlights lesser known applications as hypolipidaemic or hypoglycaemic, or as biolubricant agents and drag-reducers. Therefore, the great potentials of sPS from marine microalgae to be used as nutraceuticals, therapeutic agents, cosmetics, or in other areas, such as engineering, are approached in this review.

  1. Polysaccharide-Based Membranes in Food Packaging Applications.

    Science.gov (United States)

    Ferreira, Ana R V; Alves, Vítor D; Coelhoso, Isabel M

    2016-01-01

    Plastic packaging is essential nowadays. However, the huge environmental problem caused by landfill disposal of non-biodegradable polymers in the end of life has to be minimized and preferentially eliminated. The solution may rely on the use of biopolymers, in particular polysaccharides. These macromolecules with film-forming properties are able to produce attracting biodegradable materials, possibly applicable in food packaging. Despite all advantages of using polysaccharides obtained from different sources, some drawbacks, mostly related to their low resistance to water, mechanical performance and price, have hindered their wider use and commercialization. Nevertheless, with increasing attention and research on this field, it has been possible to trace some strategies to overcome the problems and recognize solutions. This review summarizes some of the most used polysaccharides in food packaging applications.

  2. Polysaccharide-Based Membranes in Food Packaging Applications.

    Science.gov (United States)

    Ferreira, Ana R V; Alves, Vítor D; Coelhoso, Isabel M

    2016-01-01

    Plastic packaging is essential nowadays. However, the huge environmental problem caused by landfill disposal of non-biodegradable polymers in the end of life has to be minimized and preferentially eliminated. The solution may rely on the use of biopolymers, in particular polysaccharides. These macromolecules with film-forming properties are able to produce attracting biodegradable materials, possibly applicable in food packaging. Despite all advantages of using polysaccharides obtained from different sources, some drawbacks, mostly related to their low resistance to water, mechanical performance and price, have hindered their wider use and commercialization. Nevertheless, with increasing attention and research on this field, it has been possible to trace some strategies to overcome the problems and recognize solutions. This review summarizes some of the most used polysaccharides in food packaging applications. PMID:27089372

  3. Marine Polysaccharides from Algae with Potential Biomedical Applications

    Directory of Open Access Journals (Sweden)

    Maria Filomena de Jesus Raposo

    2015-05-01

    Full Text Available There is a current tendency towards bioactive natural products with applications in various industries, such as pharmaceutical, biomedical, cosmetics and food. This has put some emphasis in research on marine organisms, including macroalgae and microalgae, among others. Polysaccharides with marine origin constitute one type of these biochemical compounds that have already proved to have several important properties, such as anticoagulant and/or antithrombotic, immunomodulatory ability, antitumor and cancer preventive, antilipidaemic and hypoglycaemic, antibiotics and anti-inflammatory and antioxidant, making them promising bioactive products and biomaterials with a wide range of applications. Their properties are mainly due to their structure and physicochemical characteristics, which depend on the organism they are produced by. In the biomedical field, the polysaccharides from algae can be used in controlled drug delivery, wound management, and regenerative medicine. This review will focus on the biomedical applications of marine polysaccharides from algae.

  4. Microwave-assisted extraction of polysaccharides from solanum nigrum

    Institute of Scientific and Technical Information of China (English)

    CHEN Xiao-qing; LIU-qin; JIANG xin-yu; ZENG fan

    2005-01-01

    The microwave-assisted method was used to extract polysaccharides from solanum nigrum. The optimum experimental parameters, mechanism of the extraction and the effect of microwave-assisted extraction process on the structures of polysaccharides were investigated. The extract was analyzed by the modified phenol-sulfuric acid method at 490 nm. The optimum experimental parameters were obtained by orthogonal experiments as follows: extraction time 15 min, microwave radiation power 455 W and the process ratio of materials mass to solvent volume 1∶20. The results show that compared with the conventional reflux extraction, the microwave-assisted extraction has a higher yield in shorter time, with no effect on the finally obtained polysaccharides as seen from the FT-IR spectra. The scanning electron microscopy images reveal that the mechanism of the extraction is related to the structural changes of the plant cells in different extracting conditions.

  5. Optimization of enzyme assisted extraction of polysaccharides from Ganoderma lucidum

    Institute of Scientific and Technical Information of China (English)

    Xu Chunhua; Tian Zhenle; Zhang Chenju; Yu Xiaobing; Zheng Huihua

    2014-01-01

    In the present work,an enzyme assisted extraction method is used to isolate crude polysaccharides from Ganoderma lucidum. The isolating effect was optimized with orthographic graph statistic method with three levels and four independent variables. Complex enzyme,extraction temperature,extraction time and ex-traction pH were combined to obtain the best possible combination to get maximum amount of extract and crude polysaccharides yield. The optimum extraction conditions were:complex enzyme amount of 3%(w/v),extrac-tion temperature at 45℃,extraction time of 3 h and extraction pH at 7. Under these conditions,the experimen-tal amount of extract is 8.9%and the yield of crude polysaccharides is 1.1%,which are in close agreement with the value predicted by the model.

  6. VISCOSITY BEHAVIOR OF LACQUER POLYSACCHARIDE IN AQUEOUS SOLUTION

    Institute of Scientific and Technical Information of China (English)

    QIU Xingping; ZHANG Lina; DU Yumin; QIAN Baogong

    1991-01-01

    The dependence of measured viscosity on NaCl concentration (0.1 to 3.0M), pH (range of 2-13) and cadoxen composition Wcad (from 2% to 100% ) for the lacquer polysaccharide in NaCl/cadoxen/H2O mixture containing HCl or without were obtained. All the viscosity exponents γ in the Mark-Houwink equations under three different solvent condition are close to 0.5. The wcad dependence of reduced viscosity ηsp/c confirms the single strand chain of the polysaccharide. As the γ values close to 0.5 and values of unperturbed dimension θ/M and [η] much smaller than those for usual linear polymers, these facts suggest that the polysaccharide chains in the aqueous solutions should be dense random coil owing to the highly branched structure.

  7. Polysaccharide-Based Membranes in Food Packaging Applications

    Directory of Open Access Journals (Sweden)

    Ana R. V. Ferreira

    2016-04-01

    Full Text Available Plastic packaging is essential nowadays. However, the huge environmental problem caused by landfill disposal of non-biodegradable polymers in the end of life has to be minimized and preferentially eliminated. The solution may rely on the use of biopolymers, in particular polysaccharides. These macromolecules with film-forming properties are able to produce attracting biodegradable materials, possibly applicable in food packaging. Despite all advantages of using polysaccharides obtained from different sources, some drawbacks, mostly related to their low resistance to water, mechanical performance and price, have hindered their wider use and commercialization. Nevertheless, with increasing attention and research on this field, it has been possible to trace some strategies to overcome the problems and recognize solutions. This review summarizes some of the most used polysaccharides in food packaging applications.

  8. Processing of Polymer Nanocomposites Reinforced with Polysaccharide Nanocrystals

    Directory of Open Access Journals (Sweden)

    Alain Dufresne

    2010-06-01

    Full Text Available Aqueous suspensions of polysaccharide (cellulose, chitin or starch nanocrystals can be prepared by acid hydrolysis of biomass. The main problem with their practical use is related to the homogeneous dispersion of these nanoparticles within a polymeric matrix. Water is the preferred processing medium. A new and interesting way for the processing of polysaccharide nanocrystals-based nanocomposites is their transformation into a co-continuous material through long chain surface chemical modification. It involves the surface chemical modification of the nanoparticles based on the use of grafting agents bearing a reactive end group and a long compatibilizing tail.

  9. Chitosan: A Promising Marine Polysaccharide for Biomedical Research.

    Science.gov (United States)

    Periayah, Mercy Halleluyah; Halim, Ahmad Sukari; Saad, Arman Zaharil Mat

    2016-01-01

    Biomaterials created 50 years ago are still receiving considerable attention for their potential to support development in the biomedical field. Diverse naturally obtained polysaccharides supply a broad range of resources applicable in the biomedical field. Lately, chitosan, a marine polysaccharide derived from chitins-which are extracted from the shells of arthropods such as crab, shrimp, and lobster-is becoming the most wanted biopolymer for use toward therapeutic interventions. This is a general short review of chitosan, highlighting the history, properties, chemical structure, processing method, and factors influencing the usage of chitosan derivatives in the biomedical field.

  10. Chitosan: A promising marine polysaccharide for biomedical research

    Directory of Open Access Journals (Sweden)

    Mercy Halleluyah Periayah

    2016-01-01

    Full Text Available Biomaterials created 50 years ago are still receiving considerable attention for their potential to support development in the biomedical field. Diverse naturally obtained polysaccharides supply a broad range of resources applicable in the biomedical field. Lately, chitosan, a marine polysaccharide derived from chitins—which are extracted from the shells of arthropods such as crab, shrimp, and lobster—is becoming the most wanted biopolymer for use toward therapeutic interventions. This is a general short review of chitosan, highlighting the history, properties, chemical structure, processing method, and factors influencing the usage of chitosan derivatives in the biomedical field.

  11. The framework of polysaccharide monooxygenase structure and chemistry.

    Science.gov (United States)

    Span, Elise A; Marletta, Michael A

    2015-12-01

    Polysaccharide monooxygenases, or PMOs (also known as lytic PMOs or LPMOs), are a group of enzymes discovered in recent years to catalyze the oxidative degradation of carbohydrate polymers. The PMO catalytic domain has a β-sandwich fold that bears a strong resemblance to both immunoglobulin (Ig) and fibronectin type III (FnIII) domains. PMOs are secreted by fungi and bacteria, and there is recent evidence for their roles in pathogenesis, in addition to biomass processing. This review addresses the biological origins and functions of emerging PMO families, as well as describes the aspects of PMO structure that support the chemistry of copper-catalyzed, oxidative polysaccharide degradation. PMID:26615470

  12. Analysis of Polysaccharides in Shii - Take fiom Guizhou

    Institute of Scientific and Technical Information of China (English)

    MO Liping; XIONG Jian; YE Jun; LI Lin

    2001-01-01

    @@ Polysaccharides, special those with physiological actions and nutrition, are widely used as an important resources for food, medicine industries, health etc. Herba Glossogynes Tenuifoliae (Shii-Take) is rich in polysaccharides with physiological actions and nutrition. Guizhou lies to the southwest of China, Natural resources abound in this province, in which there is high output and many species of Shii-Fake. So study in the Shii-Take is favor of reasonably utilizing the natural resources and getting high addvalue products. And what is more, It is necessary for energetically developing west economy.

  13. Analysis of Polysaccharides in Shii - Take fiom Guizhou

    Institute of Scientific and Technical Information of China (English)

    MO; Liping

    2001-01-01

    Polysaccharides, special those with physiological actions and nutrition, are widely used as an important resources for food, medicine industries, health etc. Herba Glossogynes Tenuifoliae (Shii-Take) is rich in polysaccharides with physiological actions and nutrition.  Guizhou lies to the southwest of China, Natural resources abound in this province, in which there is high output and many species of Shii-Fake. So study in the Shii-Take is favor of reasonably utilizing the natural resources and getting high addvalue products. And what is more, It is necessary for energetically developing west economy.……

  14. Synthesis of Oligosaccharide Fragments of the Pectic Polysaccharide Rhamnogalacturonan I

    DEFF Research Database (Denmark)

    Zakharova, Alexandra

    Pectin is a highly heterogeneous polysaccharide of plant origin. It is found in the primary cell wall and contributes to various cell functions, including support, defense, signaling, and cell adhesion. Pectin also plays important role as a food additive, serving as stabilizing and thickening agent...... in products such as jams, yoghurts and jellies. Rhamnogalacturonan I is one of the structural classes of pectic polysaccharides, along with homogalacturonan and rhamnogalacturonan II. The chemical structure of rhamnogalacturonan I is complex having a backbone consisting of alternating -linked L...

  15. Process for the production of xanthane type polysaccharides. Procede de production de polysaccharides de type xanthane

    Energy Technology Data Exchange (ETDEWEB)

    Leproux, V.; Peignier, M.; Cros, P.; Beucherie, J.; Kennel, Y.

    1990-10-02

    A fermentation process is disclosed in which microorganisms are readily grown in an emulsion medium. The invention has an objective of creating stable biopolymer emulsions which can contain up to 60% biopolymer, more particularly from 3 to 60 wt % of polysaccharides. An aqueous nutrient medium containing a carbon-hydrogen source is fermented by microorganisms so as to form an oil-in-water emulsion in the midst of which the fermentation is carried out. The nutrients, consisting of such substances as sugars, sources of organic nitrogen and/or minerals, and trace elements needed for growth, can be present at concentrations of up to 200 g/l. The microorganism used for fermentation is chosen from among the bacteria which ferment carbohydrates, preferably Xanthomonas. The oil phase may consist of any mineral or vegetable oil which is immiscible with water, preferably in an amount less than 30% of the total medium. The dispersion and stabilization of the oil phase in the water phase is favored by the presence of surfactants, preferably non-ionic. After separate sterilization of the oil and water phases, an emulsion is formed and fermentation is started in a conventional manner. According to one particular aspect of the invention, the emulsion obtained after completion of fermentation is concentrated by elimination of water so as to obtain an emulsion containing preferably 15-60 wt % polysaccharides. The emulsions of the invention are particularly applicable for treating petroleum formations and for preparing fluids used in enhanced recovery processes. Experiments are described to illustrate the invention. 2 tabs.

  16. Functional Expression of Enterobacterial O-Polysaccharide Biosynthesis Enzymes in Bacillus subtilis

    Science.gov (United States)

    Schäffer, Christina; Wugeditsch, Thomas; Messner, Paul; Whitfield, Chris

    2002-01-01

    The expression of heterologous bacterial glycosyltransferases is of interest for potential application in the emerging field of carbohydrate engineering in gram-positive organisms. To assess the feasibility of using enzymes from gram-negative bacteria, the functional expression of the genes wbaP (formerly rfbP), wecA (formerly rfe), and wbbO (formerly rfbF) from enterobacterial lipopolysaccharide O-polysaccharide biosynthesis pathways was examined in Bacillus subtilis. WbaP and WecA are initiation enzymes for O-polysaccharide formation, catalyzing the transfer of galactosyl 1-phosphate from UDP-galactose and N-acetylglucosaminyl 1-phosphate from UDP-N-acetylglucosamine, respectively, to undecaprenylphosphate. The WecA product (undecaprenylpyrophosphoryl GlcNAc) is used as an acceptor to which the bifunctional wbbO gene product sequentially adds a galactopyranose and a galactofuranose residue from the corresponding UDP sugars to form a lipid-linked trisaccharide. Genes were cloned into the shuttle vectors pRB374 and pAW10. In B. subtilis hosts, the genes were effectively transcribed under the vegII promoter control of pRB374, but the plasmids were susceptible to rearrangements and deletion. In contrast, pAW10-based constructs, in which genes were cloned downstream of the tet resistance cassette, were stable but yielded lower levels of enzyme activity. In vitro glycosyltransferase assays were performed in Escherichia coli and B. subtilis, using membrane preparations as sources of enzymes and endogenous undecaprenylphosphate as an acceptor. Incorporation of radioactivity from UDP-α-d-14C-sugar into reaction products verified the functionality of WbaP, WecA, and WbbO in either host. Enzyme activities in B. subtilis varied between 20 and 75% of those measured in E. coli. PMID:12324313

  17. Development of capsular polysaccharide-based glycoconjugates for immunization against melioidosis and glanders

    Directory of Open Access Journals (Sweden)

    Mary N Burtnick

    2012-08-01

    Full Text Available Burkholderia pseudomallei and Burkholderia mallei, the etiologic agents of melioidosis and glanders respectively, cause severe disease in humans and animals and are considered potential agents of biological warfare and terrorism. Diagnosis and treatment of infections caused by these pathogens can be challenging and, in the absence of chemotherapeutic intervention, acute disease is frequently fatal. At present, there are no human or veterinary vaccines available for immunization against these emerging/re-emerging infectious diseases. One of the long term objectives of our research, therefore, is to identify and characterize protective antigens expressed by B. pseudomallei and B. mallei and use them to develop efficacious vaccine candidates. Previous studies have demonstrated that the 6-deoxy-heptan capsular polysaccharide (CPS expressed by these bacterial pathogens is both a virulence determinant and a protective antigen. Consequently, this carbohydrate moiety has become an important component of the various subunit vaccines that we are currently developing in our laboratory. In the present study, we describe a reliable method for isolating CPS antigens from O-polysaccharide deficient strains of B. pseudomallei; including a derivative of the select agent excluded strain Bp82. Utilizing these purified CPS samples, we also describe a simple procedure for covalently linking these T-cell independent antigens to carrier proteins. In addition, we demonstrate that high titer IgG responses can be raised against the CPS component of such constructs. Collectively, these approaches provide a tangible starting point for the development of novel CPS-based glycoconjugates for immunization against melioidosis and glanders.

  18. Growth of Probiotic Bacteria in Trypticase Phytone Yeast Medium Supplemented with Crude Polysaccharides From Ganoderma lucidum

    Directory of Open Access Journals (Sweden)

    Mohd Hamim, H. M.

    2010-01-01

    Full Text Available Ganoderma lucidum is a fungus usually used in traditional Chinese medicine. The high value of G. lucidum is related to its polysaccharides content. Crude polysaccharides from G. lucidum (GLCP were obtained using hot water extraction method. There is about 0.57 g of GLCP in 1 g crude of G. lucidum. The prebiotic potential of GLCP was tested against probiotic bacteria namely: Bifidobacterium longum BB536, Bifidobacterium pseudocatenulatum G4, Lactobacillus acidophilus and Lactobacillus casei Shirota. The prebiotic potentials were studied in 10 mL basal Trypticase Phytone Yeast (abbreviated as bTPY medium (without glucose supplemented with various concentrations of GLCP (abbreviated as bTPYglcp (0.5%, 1.0%, 1.5% and 2.0%. bTPY medium supplemented with glucose (abbreviated as bTPYglu and inulin (abbreviated bTPYinu were used as comparison. Viable cell counts of the bacteria and the pH of the medium were determined during anaerobic incubation period of 0 h, 12 h, 24 h and 48 h at 37 °C. In the presence of carbohydrate source, cultures showed various degree of growth increment. With regards to the growth supporting property: bTPYglu, bTPYglu+glcp, bTPYglcp and bTPYinu were ranked first, second, third and fourth respectively. Interestingly, in bTPYglcp medium, bacterial growth increased with increasing GLCP concentrations when incubated until 24 h. B. longum BB536 was ranked first (10.53 log cfu/mL in term of their growth in this medium. Growth of B. pseudocatenulatum G4 was ranked second with 10.40 log cfu/mL. This study shows that, GLCP could support the growth of the bacteria tested.

  19. Vimentin in Bacterial Infections

    Directory of Open Access Journals (Sweden)

    Tim N. Mak

    2016-04-01

    Full Text Available Despite well-studied bacterial strategies to target actin to subvert the host cell cytoskeleton, thus promoting bacterial survival, replication, and dissemination, relatively little is known about the bacterial interaction with other components of the host cell cytoskeleton, including intermediate filaments (IFs. IFs have not only roles in maintaining the structural integrity of the cell, but they are also involved in many cellular processes including cell adhesion, immune signaling, and autophagy, processes that are important in the context of bacterial infections. Here, we summarize the knowledge about the role of IFs in bacterial infections, focusing on the type III IF protein vimentin. Recent studies have revealed the involvement of vimentin in host cell defenses, acting as ligand for several pattern recognition receptors of the innate immune system. Two main aspects of bacteria-vimentin interactions are presented in this review: the role of vimentin in pathogen-binding on the cell surface and subsequent bacterial invasion and the interaction of cytosolic vimentin and intracellular pathogens with regards to innate immune signaling. Mechanistic insight is presented involving distinct bacterial virulence factors that target vimentin to subvert its function in order to change the host cell fate in the course of a bacterial infection.

  20. A sycamore cell wall polysaccharide and a chemically related tomato leaf polysaccharide possess similar proteinase inhibitor-inducing activities.

    Science.gov (United States)

    Ryan, C A; Bishop, P; Pearce, G

    1981-09-01

    A large pectic polysaccharide, called rhamnogalacturonan I, that is solubilized by a fungal endo-alpha-1,4-polygalacturonase from the purified walls of suspension-cultured sycamore cells possesses proteinase inhibitor-inducing activity similar to that of the proteinase inhibitor-inducing factor, a pectic-like oligosaccharide fraction isolated from tomato leaves. This suggests that the proteinase inhibitor-inducing activity resides in particular polysaccharide fragments which can be released when plant cell walls are exposed to appropriate enzyme degradation as a result of either wounding or pest attack.

  1. Assessing Bacterial Interactions Using Carbohydrate-Based Microarrays

    Directory of Open Access Journals (Sweden)

    Andrea Flannery

    2015-12-01

    Full Text Available Carbohydrates play a crucial role in host-microorganism interactions and many host glycoconjugates are receptors or co-receptors for microbial binding. Host glycosylation varies with species and location in the body, and this contributes to species specificity and tropism of commensal and pathogenic bacteria. Additionally, bacterial glycosylation is often the first bacterial molecular species encountered and responded to by the host system. Accordingly, characterising and identifying the exact structures involved in these critical interactions is an important priority in deciphering microbial pathogenesis. Carbohydrate-based microarray platforms have been an underused tool for screening bacterial interactions with specific carbohydrate structures, but they are growing in popularity in recent years. In this review, we discuss carbohydrate-based microarrays that have been profiled with whole bacteria, recombinantly expressed adhesins or serum antibodies. Three main types of carbohydrate-based microarray platform are considered; (i conventional carbohydrate or glycan microarrays; (ii whole mucin microarrays; and (iii microarrays constructed from bacterial polysaccharides or their components. Determining the nature of the interactions between bacteria and host can help clarify the molecular mechanisms of carbohydrate-mediated interactions in microbial pathogenesis, infectious disease and host immune response and may lead to new strategies to boost therapeutic treatments.

  2. Polysaccharide Colloids as Smart Vehicles in Cancer Therapy.

    Science.gov (United States)

    Caro, Carlos; Pozo, David

    2015-01-01

    Cancer disease is one of the leading causes of morbidity and mortality worldwide, with approximately 14 million new cases and around 8 million cancer-related deaths yearly. Estimates expect to increase these figures over the next few years. Therefore, it is very important to develop more effective and targeted therapies. Polysaccharides are widely used for biomedical and pharmaceutical applications due to their interesting properties, and can be utilised in the production of nanovehicles for drug delivery, since they frequently extend the half-life and improve the stability of chemotherapeutic agents in bloodstream allowing them to reach the tumour tissue. Moreover, polysaccharide-based nanovehicles are generally expected to increase the therapeutic benefit by reducing the undesired side effects and promoting a more efficient cellular uptake. Here, we highlight the application of various polysaccharides as nanovehicles in cancer therapy, focusing mainly on in vivo applications and describing the main advantages of each designed system in a critical way. The use of different polysaccharides interacting with metal nanoparticles to develop new nanovehicles for cancer therapy will also be discussed. PMID:26290210

  3. Affinity purification of polysaccharide degrading enzymes with crosslinked substrates.

    NARCIS (Netherlands)

    Rozie, H.J.

    1992-01-01

    The aim of this work was to find economically favourable, affinity based, purification methods for several polysaccharide splitting bulk enzymes. The framework in which this study is done is described in Chapter 1.Chapter 2 describes the adsorption of endo-polygalacturonase (endoPG) from a commercia

  4. Galactosaminogalactan, a new immunosuppressive polysaccharide of Aspergillus fumigatus.

    Directory of Open Access Journals (Sweden)

    Thierry Fontaine

    2011-11-01

    Full Text Available A new polysaccharide secreted by the human opportunistic fungal pathogen Aspergillus fumigatus has been characterized. Carbohydrate analysis using specific chemical degradations, mass spectrometry, ¹H and ¹³C nuclear magnetic resonance showed that this polysaccharide is a linear heterogeneous galactosaminogalactan composed of α1-4 linked galactose and α1-4 linked N-acetylgalactosamine residues where both monosacharides are randomly distributed and where the percentage of galactose per chain varied from 15 to 60%. This polysaccharide is antigenic and is recognized by a majority of the human population irrespectively of the occurrence of an Aspergillus infection. GalNAc oligosaccharides are an essential epitope of the galactosaminogalactan that explains the universal antibody reaction due to cross reactivity with other antigenic molecules containing GalNAc stretches such as the N-glycans of Campylobacter jejuni. The galactosaminogalactan has no protective effect during Aspergillus infections. Most importantly, the polysaccharide promotes fungal development in immunocompetent mice due to its immunosuppressive activity associated with disminished neutrophil infiltrates.

  5. Extraction, Characterization and Immunological Activity of Polysaccharides from Rhizoma gastrodiae

    Directory of Open Access Journals (Sweden)

    Juncheng Chen

    2016-06-01

    Full Text Available A response surface and Box-Behnken design approach was applied to augment polysaccharide extraction from the residue of Rhizoma gastrodiae. Statistical analysis revealed that the linear and quadratic terms for three variables during extraction exhibited obvious effects on extraction yield. The optimum conditions were determined to be a liquid-to-solid ratio of 54 mL/g, an extraction temperature of 74 °C, an extraction time of 66 min, and three extractions. These conditions resulted in a maximum Rhizoma gastrodiae polysaccharide (RGP extraction yield of 6.11% ± 0.13%. Two homogeneous polysaccharides (RGP-1a and RGP-1b were obtained using DEAE cellulose-52 and Sephadex G-100 columns. The preliminary characterization of RGP-1a and RGP-1b was performed using HPLC-RID, HPGPC, and FTIR. Tests of the immunological activity in vitro showed that the two polysaccharides could significantly stimulate macrophages to release NO and enhance phagocytosis in a dose-dependent manner. In particular, RGP-1b (200 μg/mL and LPS (2 μg/mL had almost the same influence on the NO production and phagocytic activity of RAW 264.7 macrophages (p > 0.05. All the data obtained indicate that RGP-1a and RGP-1b have the potential to be developed as a health food.

  6. Biochemical evaluation of antioxidant activity and polysaccharides fractions in seaweeds

    Directory of Open Access Journals (Sweden)

    A. Tariq

    2015-01-01

    Full Text Available In the present study ethanol and water extracts of 15 seaweeds, Dictyota dichotoma var. velutricata, Dictyota indica, Iyengaria stellata, Padina pavonia, Sargassum swartzii, Sargassum variegatum, Stoechospermum marginatum, Stokeyia indica, Jolyna laminarioides, Caulerpa taxifolia, Halimeda tuna, Ulva fasciata, Ulva lactuca, Solieria robusta, and Melanothamnus afaqhusainii, were evaluated for their antioxidant potential by ABTS or 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid, superoxide and total antioxidant capacity (TAC assays.  The activity was concentration dependent and the variation in antioxidant potential was also observed by different assays in both extracts.  Ethanol extract of D. dichotoma var. velutricata, D. indica and S. marginatum demonstrated highest activity by TAC assay.  The antioxidant potential in organic solvent fractions of seaweeds namely P. pavonia, S. swartzii, S. marginatum and M. afaqhusainii was also determined and chloroform fraction of all the four seaweeds showed highest activity by superoxide assay.  Antioxidant activity of extracted fractions of polysaccharides from S. indica, C. taxifolia and D. dichotoma var. velutricata was also evaluated by superoxide method.  Polysaccharide fractions of S. indica obtained from HCl (at 700C and room temperature and water extract demonstrated highest activity respectively.  All the polysaccharide fractions of C. taxifolia showed excellent activity except CaClF70°C. Polysaccharide fractions of D. dichotoma var. velutricata also exhibited very good activity.

  7. Immunization of immunosuppressed patients with pneumococcal polysaccharide vaccine

    Energy Technology Data Exchange (ETDEWEB)

    Ammann, A.J.; Schiffman, G.; Addiego, J.E.; Wara, W.M.; Wara, D.W.

    The antibody response after immunization with capsular polysaccharides of Streptococcus pneumoniae of patients with Hodgkin's disease or with carcinoma of the head and neck was studied. Patients with Hodgkin's disease who were immunized prior to the institution of immunosuppressive therapy were capable of responding to each of the pneumococcal polysaccharides evaluated. The level of antibody achieved by the patients is lower than that of normal control subjects. Nevertheless, absolute values were in the range that would be expected to result in protection. The duration of antibody response was not evaluated. Patients with carcinoma of the head and neck did not demonstrate a significant increase in antibody levels after vaccination, which was done at the time of radiation therapy. Two years after immunization antibody levels were lower with recovery at three years. However, these changes were not statistically significant. Decreased levels of antibody to pneumococcal polysaccharide types not present in the vaccine were observed. Studies of patients with carcinoma of the heat and neck demonstrated that radiation therapy has a profound immunosuppressive effect on antibody levels. More selective immunosuppressive therapy and/or an increase in the immunogenicity of the polysaccharides in the vaccine are required for protection of patients with malignancy.

  8. Thermal decomposition of natural polysaccharides: Chitin and chitosan

    Directory of Open Access Journals (Sweden)

    Kuchina Yu.A.

    2015-03-01

    Full Text Available The results of the thermal analysis of shrimp’s chitin and chitosan have been presented (samples of polysaccharide differed by the deacetylation degree have been studied. The thermal analysis has been carried out by differential thermogravimetry and differential scanning calorimetry. Activation energy of process of chitin and chitosan thermal destruction has been calculated

  9. Extraction, Characterization and Immunological Activity of Polysaccharides from Rhizoma gastrodiae.

    Science.gov (United States)

    Chen, Juncheng; Tian, Shan; Shu, Xiaoying; Du, Hongtao; Li, Na; Wang, Junru

    2016-01-01

    A response surface and Box-Behnken design approach was applied to augment polysaccharide extraction from the residue of Rhizoma gastrodiae. Statistical analysis revealed that the linear and quadratic terms for three variables during extraction exhibited obvious effects on extraction yield. The optimum conditions were determined to be a liquid-to-solid ratio of 54 mL/g, an extraction temperature of 74 °C, an extraction time of 66 min, and three extractions. These conditions resulted in a maximum Rhizoma gastrodiae polysaccharide (RGP) extraction yield of 6.11% ± 0.13%. Two homogeneous polysaccharides (RGP-1a and RGP-1b) were obtained using DEAE cellulose-52 and Sephadex G-100 columns. The preliminary characterization of RGP-1a and RGP-1b was performed using HPLC-RID, HPGPC, and FTIR. Tests of the immunological activity in vitro showed that the two polysaccharides could significantly stimulate macrophages to release NO and enhance phagocytosis in a dose-dependent manner. In particular, RGP-1b (200 μg/mL) and LPS (2 μg/mL) had almost the same influence on the NO production and phagocytic activity of RAW 264.7 macrophages (p > 0.05). All the data obtained indicate that RGP-1a and RGP-1b have the potential to be developed as a health food. PMID:27347944

  10. Polysaccharides of higher fungi: Biological role, structure, and antioxidative activity

    OpenAIRE

    Kozarski Maja S.; Klaus Anita S.; Nikšić Miomir P.; van Griensven Leo J.L.D.; Vrvić Miroslav M.; Jakovljević Dragica M.

    2014-01-01

    Fungal polysaccharides attract a lot of attention due to their multiple challenging biological properties, such as: anti-tumor, anti-viral, anticomplementary, anticoagulant, hypolipidemic and immunomodulatory and immune-stimulatory activities, which all together make them suitable for application in many quite distinctive areas, such as food industry, biomedicine, cosmetology, agriculture, environmental protection and waste water management. This article pr...

  11. Structure of pectic polysaccharides from sunflower salts-soluble fraction

    Science.gov (United States)

    The manuscript discusses the structural features of pectin polysaccharides extracted from seedless sunflower head residues. The analysis using 1H, 13C and two-dimensional gHSQC NMR showed various numbers of methyl and hydroxyl groups attached to the anomeric carbons in the pectin backbone at differe...

  12. Determining the polysaccharide composition of plant cell walls.

    Science.gov (United States)

    Pettolino, Filomena A; Walsh, Cherie; Fincher, Geoffrey B; Bacic, Antony

    2012-09-01

    The plant cell wall is a chemically complex structure composed mostly of polysaccharides. Detailed analyses of these cell wall polysaccharides are essential for our understanding of plant development and for our use of plant biomass (largely wall material) in the food, agriculture, fabric, timber, biofuel and biocomposite industries. We present analytical techniques not only to define the fine chemical structures of individual cell wall polysaccharides but also to estimate the overall polysaccharide composition of cell wall preparations. The procedure covers the preparation of cell walls, together with gas chromatography-mass spectrometry (GC-MS)-based methods, for both the analysis of monosaccharides as their volatile alditol acetate derivatives and for methylation analysis to determine linkage positions between monosaccharide residues as their volatile partially methylated alditol acetate derivatives. Analysis time will vary depending on both the method used and the tissue type, and ranges from 2 d for a simple neutral sugar composition to 2 weeks for a carboxyl reduction/methylation linkage analysis. PMID:22864200

  13. Directional control of diffusion and swelling in megamolecular polysaccharide hydrogels.

    Science.gov (United States)

    Joshi, G; Okeyoshi, K; Okajima, M K; Kaneko, T

    2016-07-01

    Directional control of diffusion and swelling in megamolecular polysaccharide hydrogels is demonstrated by focusing on the anisotropic structures for water absorption. Due to the presence of a layered structure in the hydrogel, the directional control for diffusion parallel to the planar direction and swelling in the lateral direction are possible. PMID:27223843

  14. Pectin, a versatile polysaccharide present in plant cell walls

    NARCIS (Netherlands)

    Voragen, A.G.J.; Coenen, G.J.; Verhoef, R.P.; Schols, H.A.

    2009-01-01

    Pectin or pectic substances are collective names for a group of closely associated polysaccharides present in plant cell walls where they contribute to complex physiological processes like cell growth and cell differentiation and so determine the integrity and rigidity of plant tissue. They also pla

  15. The digestion of yeast cell wall polysaccharides in veal calves

    NARCIS (Netherlands)

    Gaillard, B.D.E.; Weerden, van E.J.

    1976-01-01

    1. The digestibility of the cell wall polysaccharides of an alkane-grown yeast in different parts of the digestive tract of two veal calves fitted with re-entrant cannulas at the end of the ileum was studied by replacing part of the skim-milk powder of their ‘normal’, milk-substitute (all-milk-prote

  16. Polysaccharide Colloids as Smart Vehicles in Cancer Therapy.

    Science.gov (United States)

    Caro, Carlos; Pozo, David

    2015-01-01

    Cancer disease is one of the leading causes of morbidity and mortality worldwide, with approximately 14 million new cases and around 8 million cancer-related deaths yearly. Estimates expect to increase these figures over the next few years. Therefore, it is very important to develop more effective and targeted therapies. Polysaccharides are widely used for biomedical and pharmaceutical applications due to their interesting properties, and can be utilised in the production of nanovehicles for drug delivery, since they frequently extend the half-life and improve the stability of chemotherapeutic agents in bloodstream allowing them to reach the tumour tissue. Moreover, polysaccharide-based nanovehicles are generally expected to increase the therapeutic benefit by reducing the undesired side effects and promoting a more efficient cellular uptake. Here, we highlight the application of various polysaccharides as nanovehicles in cancer therapy, focusing mainly on in vivo applications and describing the main advantages of each designed system in a critical way. The use of different polysaccharides interacting with metal nanoparticles to develop new nanovehicles for cancer therapy will also be discussed.

  17. Mapping the polysaccharide degradation potential of Aspergillus niger

    NARCIS (Netherlands)

    Andersen, M.R.; Giese, M.; De Vries, R.P.; Nielsen, J.

    2012-01-01

    Background The degradation of plant materials by enzymes is an industry of increasing importance. For sustainable production of second generation biofuels and other products of industrial biotechnology, efficient degradation of non-edible plant polysaccharides such as hemicellulose is required. For

  18. Interpenetrating polymer network hydrogels based on polysaccharides for biomedical applications

    NARCIS (Netherlands)

    Pescosolido, L.

    2011-01-01

    The main theme of this thesis is the development and the characterization of interpenetrating polymer network hydrogels (IPNs) based on biodegradable and biocompatible polysaccharides, in particular alginate, hyaluronic acid and dextran. The suitability of these novel systems as pharmaceutical and b

  19. Specific medicinal plant polysaccharides effectively enhance the potency of a DC-based vaccine against mouse mammary tumor metastasis.

    Directory of Open Access Journals (Sweden)

    Wei Ting Chang

    Full Text Available Dendritic cell (DC vaccines are a newly emerging immunotherapeutic approach for the treatment and prevention of cancer, but major challenges still remain particularly with respect to clinical efficacy. Engineering and optimization of adjuvant formulations for DC-based vaccines is one strategy through which more efficacious treatments may be obtained. In this study, we developed a new ex vivo approach for DC vaccine preparation. We evaluated two highly purified mixed polysaccharide fractions from the root of Astragalus membranaceus and Codonopsis pilosulae, named Am and Cp, for their use in enhancing the efficiency of a DC-based cancer vaccine against metastasis of 4T1 mammary carcinoma in mice. Mixed lymphocyte reaction showed all Am-, Cp- and [Am+Cp]-treated DCs enhanced mouse CD4+ and CD8+ T-cell proliferation. [Am+Cp]-treated DCs exhibited the strongest anti-4T1 metastasis activity in test mice. Treatments with Am, Cp and [Am+Cp] also resulted in augmented expression of CD40, CD80 and CD86 markers in test DCs. Bioinformatics analysis of the cytokine array data from treated DCs identified that [Am+Cp] is efficacious in activation of specific immune functions via mediating the expression of cytokines/chemokines involved in the recruitment and differentiation of defined immune cells. Biochemical analysis revealed that Am and Cp are composed mainly of polysaccharides containing a high level (70-95% glucose residues, but few or no (< 1% mannose residues. In summary, our findings suggest that the specific plant polysaccharides Am and Cp extracted from traditional Chinese medicines can be effectively used instead of bacterial LPS as a potent adjuvant in the formulation of a DC-based vaccine for cancer immunotherapies.

  20. Xylan utilization in human gut commensal bacteria is orchestrated by unique modular organization of polysaccharide-degrading enzymes

    KAUST Repository

    Zhang, Meiling

    2014-08-18

    Enzymes that degrade dietary and host-derived glycans represent the most abundant functional activities encoded by genes unique to the human gut microbiome. However, the biochemical activities of a vast majority of the glycan-degrading enzymes are poorly understood. Here, we use transcriptome sequencing to understand the diversity of genes expressed by the human gut bacteria Bacteroides intestinalis and Bacteroides ovatus grown in monoculture with the abundant dietary polysaccharide xylan. The most highly induced carbohydrate active genes encode a unique glycoside hydrolase (GH) family 10 endoxylanase (BiXyn10A or BACINT-04215 and BACOVA-04390) that is highly conserved in the Bacteroidetes xylan utilization system. The BiXyn10A modular architecture consists of a GH10 catalytic module disrupted by a 250 amino acid sequence of unknown function. Biochemical analysis of BiXyn10A demonstrated that such insertion sequences encode a new family of carbohydrate-binding modules (CBMs) that binds to xy-lose- configured oligosaccharide/polysaccharide ligands, the substrate of the BiXyn10A enzymatic activity. The crystal structures of CBM1 from BiXyn10A (1.8 Å), a cocomplex of BiXyn10A CBM1 with xylohexaose (1.14 Å), and the CBM fromits homolog in the Prevotella bryantii B 14 Xyn10C (1.68 Å) reveal an unanticipated mode for ligand binding. Aminimal enzyme mix, composed of the gene products of four of the most highly up-regulated genes during growth on wheat arabinoxylan, depolymerizes the polysaccharide into its component sugars. The combined biochemical and biophysical studies presented here provide a framework for understanding fiber metabolism by an important group within the commensal bacterial population known to influence human health.

  1. In vitro anti-influenza virus activities of sulfated polysaccharide fractions from Gracilaria lemaneiformis.

    Science.gov (United States)

    Chen, Mei-Zhen; Xie, Hao-Gui; Yang, La-Wei; Liao, Zao-Hui; Yu, Jie

    2010-10-01

    In this paper, in vitro anti-influenza virus activities of sulfated polysaccharide fractions from Gracilaria lemaneiformis were investigated. Cytotoxicities and antiviral activities of Gracilaria lemaneiformis polysaccharides (PGL), Gracilaria lemaneiformis polysaccharide fraction-1 (GL-1), Gracilaria lemaneiformis polysaccharide fraction-2 (GL-2) and Gracilaria lemaneiformis polysaccharide fraction-3 (GL-3) were studied by the Methyl thiazolyl tetrazolium (MTT) method, and the inhibitory effect against Human influenza virus H1-364 induced cytopathic effect (CPE) on MDCK cells were observed by the CPE method. In addition, the antiviral mechanism of PGL was explored by Plaque forming unit (PFU), MTT and CPE methods. The results showed: i) Cytotoxicities were not significantly revealed, and H1-364 induced CPE was also reduced treated with sulfated polysaccharide fractions from Gracilaria lemaneiformis; ii) Antiviral activities were associated with the mass percentage content of sulfate groups in polysaccharide fractions, which was about 13%, in polysaccharides (PGL and GL-2) both of which exhibited higher antiviral activity; iii) A potential antiviral mechanism to explain these observations is that viral adsorption and replication on host cells were inhibited by sulfated polysaccharides from Gracilaria lemaneiformis. In conclusion, Anti-influenza virus activities of sulfated polysaccharide fractions from Gracilaria lemaneiformis were revealed, and the antiviral activities were associated with content of sulfate groups in polysaccharide fractions.

  2. Pleurotus tuber-regium Polysaccharides Attenuate Hyperglycemia and Oxidative Stress in Experimental Diabetic Rats

    Directory of Open Access Journals (Sweden)

    Hui-Yu Huang

    2012-01-01

    Full Text Available Pleurotus tuber-regium contains polysaccharides that are responsible for pharmacological actions, and medicinal effects of these polysaccharides have not yet been studied in diabetic rats. We examined the antidiabetic, antihyperlipidemic, and antioxidant properties of P. tuber-regium polysaccharides in experimental diabetic rats. Forty rats were equally assigned as diabetic high-fat (DHF diet and polysaccharides treated DHF groups (DHF+1P, DHF+2P, and DHF+3P, 20 mg/kg bodyweight/8-week. Diabetes was induced by chronic low-dose streptozotocin injections and a high-fat diet to mimic type 2 diabetes. Polysaccharides (1P, 2P, and 3P were extracted from three different strains of P. tuber-regium. Fasting blood glucose and glycosylated hemoglobin (HbA1c levels substantially decreased, while serum insulin levels were restored by polysaccharides treatment compared to DHF. Furthermore, plasma total cholesterol, triglycerides, and low-density lipoprotein levels were significantly (P<0.01 lower in polysaccharide groups. High-density lipoprotein levels were attenuated with polysaccharides against diabetes condition. Polysaccharides inhibited (P<0.01 the lipid peroxidation index (malondialdehyde, and restored superoxide dismutase and glutathione peroxidase activities in the liver of diabetic rats. The antihyperglycemic property of polysaccharides perhaps boosts the antioxidant system that attenuates oxidative stress. We emphasize that P. tuber-regium polysaccharides can be considered as an alternative medicine to treat hyperglycemia and oxidative stress in diabetic rats.

  3. Non-cellulosic polysaccharides from cotton fibre are differently impacted by textile processing

    DEFF Research Database (Denmark)

    Runavot, Jean-Luc; Guo, Xiaoyuan; Willats, William George Tycho;

    2014-01-01

    Cotton fibre is mainly composed of cellulose, although non-cellulosic polysaccharides play key roles during fibre development and are still present in the harvested fibre. This study aimed at determining the fate of non-cellulosic polysaccharides during cotton textile processing. We analyzed non......-cellulosic cotton fibre polysaccharides during different steps of cotton textile processing using GC-MS, HPLC and comprehensive microarray polymer profiling to obtain monosaccharide and polysaccharide amounts and linkage compositions. Additionally, in situ detection was used to obtain information on polysaccharide...... localization and accessibility. We show that pectic and hemicellulosic polysaccharide levels decrease during cotton textile processing and that some processing steps have more impact than others. Pectins and arabinose-containing polysaccharides are strongly impacted by the chemical treatments, with most being...

  4. Engineering bacterial biopolymers for the biosorption of heavy metals; new products and novel formulations

    International Nuclear Information System (INIS)

    Bioremediation of heavy metal pollution remains a major challenge in environmental biotechnology. One of the approaches considered for application involves biosorption either to biomass or to isolated biopolymers. Many bacterial polysaccharides have been shown to bind heavy metals with varying degrees of specificity and affinity. While various approaches have been adopted to generate polysaccharide variants altered in both structure and activity, metal biosorption has not been examined. Polymer engineering has included structural modification through the introduction of heterologous genes of the biosynthetic pathway into specific mutants, leading either to alterations in polysaccharide backbone or side chains, or to sugar modification. In addition, novel formulations can be designed which enlarge the family of available bacterial biopolymers for metal-binding and subsequent recovery. An example discussed here is the use of amphipathic bioemulsifiers such as emulsan, produced by the oil-degrading Acinetobacter lwoffii RAG-1, that forms stable, concentrated (70%), oil-in-water emulsions (emulsanosols). In this system metal ions bind primarily at the oil/water interface, enabling their recovery and concentration from relatively dilute solutions. In addition to the genetic modifications described above, a new approach to the generation of amphipathic bioemulsifying formulations is based on the interaction of native or recombinant esterase and its derivatives with emulsan and other water-soluble biopolymers. Cation-binding emulsions are generated from a variety of hydrophobic substrates. The features of these and other systems will be discussed, together with a brief consideratiton of possible applications. (orig.)

  5. Engineering bacterial biopolymers for the biosorption of heavy metals; new products and novel formulations

    Energy Technology Data Exchange (ETDEWEB)

    Gutnick, D.L.; Bach, H. [Tel-Aviv Univ. (Israel). Dept. of Molecular Microbiology and Biotechnology

    2000-07-01

    Bioremediation of heavy metal pollution remains a major challenge in environmental biotechnology. One of the approaches considered for application involves biosorption either to biomass or to isolated biopolymers. Many bacterial polysaccharides have been shown to bind heavy metals with varying degrees of specificity and affinity. While various approaches have been adopted to generate polysaccharide variants altered in both structure and activity, metal biosorption has not been examined. Polymer engineering has included structural modification through the introduction of heterologous genes of the biosynthetic pathway into specific mutants, leading either to alterations in polysaccharide backbone or side chains, or to sugar modification. In addition, novel formulations can be designed which enlarge the family of available bacterial biopolymers for metal-binding and subsequent recovery. An example discussed here is the use of amphipathic bioemulsifiers such as emulsan, produced by the oil-degrading Acinetobacter lwoffii RAG-1, that forms stable, concentrated (70%), oil-in-water emulsions (emulsanosols). In this system metal ions bind primarily at the oil/water interface, enabling their recovery and concentration from relatively dilute solutions. In addition to the genetic modifications described above, a new approach to the generation of amphipathic bioemulsifying formulations is based on the interaction of native or recombinant esterase and its derivatives with emulsan and other water-soluble biopolymers. Cation-binding emulsions are generated from a variety of hydrophobic substrates. The features of these and other systems will be discussed, together with a brief consideratiton of possible applications. (orig.)

  6. Interfering with bacterial gossip

    DEFF Research Database (Denmark)

    Bjarnsholt, Thomas; Tolker-Nielsen, Tim; Givskov, Michael

    2011-01-01

    defense. Antibiotics exhibit a rather limited effect on biofilms. Furthermore, antibiotics have an ‘inherent obsolescence’ because they select for development of resistance. Bacterial infections with origin in bacterial biofilms have become a serious threat in developed countries. Pseudomonas aeruginosa...... that appropriately target bacteria in their relevant habitat with the aim of mitigating their destructive impact on patients. In this review we describe molecular mechanisms involved in “bacterial gossip” (more scientifically referred to as quorum sensing (QS) and c-di-GMP signaling), virulence, biofilm formation...

  7. The Azospirillum brasilense Sp7 noeJ and noeL genes are involved in extracellular polysaccharide biosynthesis.

    Science.gov (United States)

    Lerner, Anat; Castro-Sowinski, Susana; Valverde, Angel; Lerner, Hadas; Dror, Rachel; Okon, Yaacov; Burdman, Saul

    2009-12-01

    Azospirillum brasilense is a plant root-colonizing bacterium that exerts beneficial effects on the growth of many agricultural crops. Extracellular polysaccharides of the bacterium play an important role in its interactions with plant roots. The pRhico plasmid of A. brasilense Sp7, also named p90, carries several genes involved in synthesis and export of cell surface polysaccharides. We generated two Sp7 mutants impaired in two pRhico-located genes, noeJ and noeL, encoding mannose-6-phosphate isomerase and GDP-mannose 4,6-dehydratase, respectively. Our results demonstrate that in A. brasilense Sp7, noeJ and noeL are involved in lipopolysaccharide and exopolysaccharide synthesis. noeJ and noeL mutant strains were significantly altered in their outer membrane and cytoplasmic/periplasmic protein profiles relative to the wild-type strain. Moreover, both noeJ and noeL mutations significantly affected the bacterial responses to several stresses and antimicrobial compounds. Disruption of noeL, but not noeJ, affected the ability of the A. brasilense Sp7 to form biofilms. The pleiotropic alterations observed in the mutants could be due, at least partially, to their altered lipopolysaccharides and exopolysaccharides relative to the wild-type.

  8. Structure of the capsular polysaccharide of Acinetobacter baumannii 1053 having the KL91 capsule biosynthesis gene locus.

    Science.gov (United States)

    Shashkov, Alexander S; Shneider, Mikhail M; Senchenkova, Sof'ya N; Popova, Anastasiya V; Nikitina, Anastasia S; Babenko, Vladislav V; Kostryukova, Elena S; Miroshnikov, Konstantin A; Volozhantsev, Nikolay V; Knirel, Yuriy A

    2015-03-01

    Acinetobacter baumannii 1053 is the type strain for the maintenance of specific bacteriophage AP22, which infects a fairly broad range of A. baumannii strains circulating in Russian clinics and hospitals. A capsular polysaccharide (CPS) was isolated from cells of strain 1053 and studied by sugar analysis along with 1D and 2D (1)H and (13)C NMR spectroscopy. The following structure of the linear trisaccharide repeating unit was established: -->4)-β-D-ManpNAcA-(1-->4)-β-D-ManpNAcA-(1-->3)-α-D-FucpNAc-(1--> where ManNAcA and FucNAc indicate 2-acetamido-2-deoxymannuronic acid and 2-acetamido-2,6-dideoxygalactose, respectively. A polysaccharide having the same repeating unit but a shorter chain was isolated by the phenol-water extraction of bacterial cells. Sequencing of the CPS biosynthesis gene locus showed that A. baumannii 1053 belongs to a new group designated KL91. The gene functions assigned putatively by a comparison with available databases were in agreement with the CPS structure established.

  9. Effect of co-administration of probiotics with polysaccharide based colon targeted delivery systems to optimize site specific drug release.

    Science.gov (United States)

    Prudhviraj, G; Vaidya, Yogyata; Singh, Sachin Kumar; Yadav, Ankit Kumar; Kaur, Puneet; Gulati, Monica; Gowthamarajan, K

    2015-11-01

    Significant clinical success of colon targeted dosage forms has been limited by their inappropriate release profile at the target site. Their failure to release the drug completely in the colon may be attributed to changes in the colonic milieu because of pathological state, drug effect and psychological stress accompanying the diseased state or, a combination of these. Alteration in normal colonic pH and bacterial picture leads to incomplete release of drug from the designed delivery system. We report the effectiveness of a targeted delivery system wherein the constant replenishment of the colonic microbiota is achieved by concomitant administration of probiotics along with the polysaccharide based drug delivery system. Guar gum coated spheroids of sulfasalazine were prepared. In the dissolution studies, these spheroids showed markedly higher release in the simulated colonic fluid. In vivo experiments conducted in rats clearly demonstrated the therapeutic advantage of co-administration of probiotics with guar gum coated spheroids. Our results suggest that concomitant use of probiotics along with the polysaccharide based delivery systems can be a simple strategy to achieve satisfactory colon targeting of drugs.

  10. Digestion by pigs of non-starch polysaccharides in wheat and raw peas (Pisum sativum) fed in mixed diets.

    Science.gov (United States)

    Goodlad, J S; Mathers, J C

    1991-03-01

    The digestion by pigs of non-starch polysaccharides (NSP) in wheat and raw peas (Pisum sativum) fed in mixed diets was measured. In the four experimental diets, wheat was included at a constant 500 g/kg whilst peas contributed 0-300 g/kg and these were the only dietary sources of NSP. Separate estimates of digestibility for wheat and peas were obtained by using a multiple linear regression technique which also tested the possibility that the presence of peas might influence the digestibility of wheat NSP. There was little evidence of the latter and it was found that the digestibility of peas NSP (0.84) was considerably greater than that of wheat (0.65). The non-cellulosic polysaccharides (NCP) had twofold greater digestibilities than had cellulose for both foods with essentially all the peas NCP being digested. Faecal alpha, epsilon-diaminopimelic acid concentration increased with feeding of peas, suggesting stimulation of bacterial biomass production in the large intestine using the readily fermented peas NSP. All three major volatile fatty acids produced by large intestinal fermentation were detected in jugular blood and increased significantly with increasing peas inclusion rate in the diet.

  11. Arabidopsis and Brachypodium distachyon transgenic plants expressing Aspergillus nidulans acetylesterases have decreased degree of polysaccharide acetylation and increased resistance to pathogens.

    Science.gov (United States)

    Pogorelko, Gennady; Lionetti, Vincenzo; Fursova, Oksana; Sundaram, Raman M; Qi, Mingsheng; Whitham, Steven A; Bogdanove, Adam J; Bellincampi, Daniela; Zabotina, Olga A

    2013-05-01

    The plant cell wall has many significant structural and physiological roles, but the contributions of the various components to these roles remain unclear. Modification of cell wall properties can affect key agronomic traits such as disease resistance and plant growth. The plant cell wall is composed of diverse polysaccharides often decorated with methyl, acetyl, and feruloyl groups linked to the sugar subunits. In this study, we examined the effect of perturbing cell wall acetylation by making transgenic Arabidopsis (Arabidopsis thaliana) and Brachypodium (Brachypodium distachyon) plants expressing hemicellulose- and pectin-specific fungal acetylesterases. All transgenic plants carried highly expressed active Aspergillus nidulans acetylesterases localized to the apoplast and had significant reduction of cell wall acetylation compared with wild-type plants. Partial deacetylation of polysaccharides caused compensatory up-regulation of three known acetyltransferases and increased polysaccharide accessibility to glycosyl hydrolases. Transgenic plants showed increased resistance to the fungal pathogens Botrytis cinerea and Bipolaris sorokiniana but not to the bacterial pathogens Pseudomonas syringae and Xanthomonas oryzae. These results demonstrate a role, in both monocot and dicot plants, of hemicellulose and pectin acetylation in plant defense against fungal pathogens.

  12. Bacterial Wound Culture

    Science.gov (United States)

    ... Home Visit Global Sites Search Help? Bacterial Wound Culture Share this page: Was this page helpful? Also known as: Aerobic Wound Culture; Anaerobic Wound Culture Formal name: Culture, wound Related ...

  13. Bacterial intermediate filaments

    DEFF Research Database (Denmark)

    Charbon, Godefroid; Cabeen, M.; Jacobs-Wagner, C.

    2009-01-01

    Crescentin, which is the founding member of a rapidly growing family of bacterial cytoskeletal proteins, was previously proposed to resemble eukaryotic intermediate filament (IF) proteins based on structural prediction and in vitro polymerization properties. Here, we demonstrate that crescentin...

  14. Bacterial Meningitis in Infants

    Directory of Open Access Journals (Sweden)

    J Gordon Millichap

    2004-04-01

    Full Text Available A retrospective study of 80 infantile patients (ages 30-365 days; 47 male, 33 female with culture-proven bacterial meningitis seen over a 16 year period (1986-2001 is reported from Taiwan.

  15. Prilling and supercritical drying: A successful duo to produce core-shell polysaccharide aerogel beads for wound healing.

    Science.gov (United States)

    De Cicco, Felicetta; Russo, Paola; Reverchon, Ernesto; García-González, Carlos A; Aquino, Rita Patrizia; Del Gaudio, Pasquale

    2016-08-20

    Bacterial infections often affect the wound, delaying healing and causing areas of necrosis. In this work, an aerogel in form of core-shell particles, able to prolong drug activity on wounds and to be easily removed was developed. Aerogel microcapsules consisted of a core made by amidated pectin hosting doxycycline, an antibiotic drug with a broad spectrum of action, and a shell consisting of high mannuronic content alginate. Particles were obtained by prilling using a coaxial nozzle for drop production and an ethanolic solution of CaCl2 as gelling promoter. The alcogels where dried using supercritical CO2. The influence of polysaccharides and drug concentrations on aerogel properties was evaluated. Spherical particles with high drug encapsulation efficiency (87%) correlated to alginate concentration in the processed liquid feeds were obtained. The release of the drug, mainly concentrated into the pectin core, was prolonged till 48h, and dependent on both drug/pectin ratio and alginate concentration.

  16. Prilling and supercritical drying: A successful duo to produce core-shell polysaccharide aerogel beads for wound healing.

    Science.gov (United States)

    De Cicco, Felicetta; Russo, Paola; Reverchon, Ernesto; García-González, Carlos A; Aquino, Rita Patrizia; Del Gaudio, Pasquale

    2016-08-20

    Bacterial infections often affect the wound, delaying healing and causing areas of necrosis. In this work, an aerogel in form of core-shell particles, able to prolong drug activity on wounds and to be easily removed was developed. Aerogel microcapsules consisted of a core made by amidated pectin hosting doxycycline, an antibiotic drug with a broad spectrum of action, and a shell consisting of high mannuronic content alginate. Particles were obtained by prilling using a coaxial nozzle for drop production and an ethanolic solution of CaCl2 as gelling promoter. The alcogels where dried using supercritical CO2. The influence of polysaccharides and drug concentrations on aerogel properties was evaluated. Spherical particles with high drug encapsulation efficiency (87%) correlated to alginate concentration in the processed liquid feeds were obtained. The release of the drug, mainly concentrated into the pectin core, was prolonged till 48h, and dependent on both drug/pectin ratio and alginate concentration. PMID:27178955

  17. Dietary supplementation with soluble plantain non-starch polysaccharides inhibits intestinal invasion of Salmonella Typhimurium in the chicken.

    Science.gov (United States)

    Parsons, Bryony N; Wigley, Paul; Simpson, Hannah L; Williams, Jonathan M; Humphrey, Suzie; Salisbury, Anne-Marie; Watson, Alastair J M; Fry, Stephen C; O'Brien, David; Roberts, Carol L; O'Kennedy, Niamh; Keita, Asa V; Söderholm, Johan D; Rhodes, Jonathan M; Campbell, Barry J

    2014-01-01

    Soluble fibres (non-starch polysaccharides, NSP) from edible plants but particularly plantain banana (Musa spp.), have been shown in vitro and ex vivo to prevent various enteric pathogens from adhering to, or translocating across, the human intestinal epithelium, a property that we have termed contrabiotic. Here we report that dietary plantain fibre prevents invasion of the chicken intestinal mucosa by Salmonella. In vivo experiments were performed with chicks fed from hatch on a pellet diet containing soluble plantain NSP (0 to 200 mg/d) and orally infected with S.Typhimurium 4/74 at 8 d of age. Birds were sacrificed 3, 6 and 10 d post-infection. Bacteria were enumerated from liver, spleen and caecal contents. In vitro studies were performed using chicken caecal crypts and porcine intestinal epithelial cells infected with Salmonella enterica serovars following pre-treatment separately with soluble plantain NSP and acidic or neutral polysaccharide fractions of plantain NSP, each compared with saline vehicle. Bacterial adherence and invasion were assessed by gentamicin protection assay. In vivo dietary supplementation with plantain NSP 50 mg/d reduced invasion by S.Typhimurium, as reflected by viable bacterial counts from splenic tissue, by 98.9% (95% CI, 98.1-99.7; Pcell-line (73% mean inhibition (95% CI, 64-81); Pcells and Ussing chamber experiments with ex-vivo human ileal mucosa showed that this effect was associated with increased short circuit current but no change in electrical resistance. The inhibitory activity of plantain NSP lay mainly within the acidic/pectic (homogalacturonan-rich) component. Supplementation of chick feed with plantain NSP was well tolerated and shows promise as a simple approach for reducing invasive salmonellosis.

  18. Dietary supplementation with soluble plantain non-starch polysaccharides inhibits intestinal invasion of Salmonella Typhimurium in the chicken.

    Science.gov (United States)

    Parsons, Bryony N; Wigley, Paul; Simpson, Hannah L; Williams, Jonathan M; Humphrey, Suzie; Salisbury, Anne-Marie; Watson, Alastair J M; Fry, Stephen C; O'Brien, David; Roberts, Carol L; O'Kennedy, Niamh; Keita, Asa V; Söderholm, Johan D; Rhodes, Jonathan M; Campbell, Barry J

    2014-01-01

    Soluble fibres (non-starch polysaccharides, NSP) from edible plants but particularly plantain banana (Musa spp.), have been shown in vitro and ex vivo to prevent various enteric pathogens from adhering to, or translocating across, the human intestinal epithelium, a property that we have termed contrabiotic. Here we report that dietary plantain fibre prevents invasion of the chicken intestinal mucosa by Salmonella. In vivo experiments were performed with chicks fed from hatch on a pellet diet containing soluble plantain NSP (0 to 200 mg/d) and orally infected with S.Typhimurium 4/74 at 8 d of age. Birds were sacrificed 3, 6 and 10 d post-infection. Bacteria were enumerated from liver, spleen and caecal contents. In vitro studies were performed using chicken caecal crypts and porcine intestinal epithelial cells infected with Salmonella enterica serovars following pre-treatment separately with soluble plantain NSP and acidic or neutral polysaccharide fractions of plantain NSP, each compared with saline vehicle. Bacterial adherence and invasion were assessed by gentamicin protection assay. In vivo dietary supplementation with plantain NSP 50 mg/d reduced invasion by S.Typhimurium, as reflected by viable bacterial counts from splenic tissue, by 98.9% (95% CI, 98.1-99.7; Pplantain NSP (5-10 mg/ml) inhibited adhesion of S.Typhimurium 4/74 to a porcine epithelial cell-line (73% mean inhibition (95% CI, 64-81); Peffect on the epithelial cells and Ussing chamber experiments with ex-vivo human ileal mucosa showed that this effect was associated with increased short circuit current but no change in electrical resistance. The inhibitory activity of plantain NSP lay mainly within the acidic/pectic (homogalacturonan-rich) component. Supplementation of chick feed with plantain NSP was well tolerated and shows promise as a simple approach for reducing invasive salmonellosis. PMID:24498347

  19. Sulfated Polysaccharides Purified from Two Species of Padina Improve Collagen and Epidermis Formation in the Rat

    Science.gov (United States)

    Kordjazi, Moazameh; Shabanpour, Bahareh; Zabihi, Ebrahim; Faramarzi, Mohammad Ali; Feizi, Farideh; Ahmadi Gavlighi, Hassan; Feghhi, Mohammad Amin; Hosseini, Seyed Abbas

    2013-01-01

    Sulfated polysaccharides have shown promising effects on wound healing processes along with many other biological activities. The sulfated polysaccharides extracted from two algae species habitats in Persian Gulf were studied in vivo for their effects on collagen formation and epidermal regeneration. The polysaccharides were purified from aqueous extracts of P. tetrastromatica and P. boergesenii using CaCl2 and ethanol precipitation. The sulfate content of each polysaccharide was determined. Two identical wounds (either burn or excision) were made on the back of 4 groups of male Wistar rats (10 rats per group) under anesthesia. The algal polysaccharide ointments (2%) were applied twice daily on one side and the other wound was treated with Eucerin (as control). The rats were sacrificed on day 7 or 14, and then the wound samples were examined for epidermal thickness by light microscope. Furthermore, hydroxyproline content (as a marker of collagen formation) was spectro-photometrically measured. The polysaccharides purified from P. boergesenii had higher sulfate content (32.6±1%) compared to P. tetrastromatica (19±1%). Both algal polysaccharides showed some improvements in collagen formation (hydroxyproline content) and epidermal thickness in both wound models compared to the vehicle. The sulfated polysaccharides purified from P. tetrastromatica and P. boergesenii seaweeds are able to induce collagen formation and epidermal regeneration in the two wound models. The superior healing properties of P. boergesenii polysaccharides might be correlated to its higher sulfate content. Both algal polysaccharides are good candidates for wound healing clinical trials. PMID:24551807

  20. Optimization of the purification process of Haemophilus influenzae type b polysaccharide%b型流感嗜血杆菌多糖纯化工艺的优化

    Institute of Scientific and Technical Information of China (English)

    王伟; 马雷钧; 沈坚; 陈晓怿; 马相虎

    2014-01-01

    目的 优化b型流感嗜血杆菌(Haemophilus influenzae type b,Hib)多糖纯化工艺,替代传统的苯酚结合乙醇方法.方法 采用十六烷基三甲基溴化铵提取粗糖,以脱氧胆酸钠结合乙醇多级纯化进一步纯化粗糖,通过超滤浓缩和除菌过滤获得纯化的Hib多糖.采用优化的纯化工艺以中试和放大规模各纯化3批Hib多糖,按照《中华人民共和国药典》2010年版三部的要求检测纯化的Hib多糖.结果 中试和放大规模纯化的各3批Hib多糖的相对分子质量分别为621 800、634 400、659 900和597 200、612 100、583 400,均符合规定的标准.中试和放大规模纯化的各3批Hib多糖的细菌内毒素含量分别为2.0、0.5、0.7 EU/μg和4.0、2.0、1.0 EU/μg,均明显低于规定的标准.鉴别试验显示,中试和放大规模纯化的各批Hib多糖均可与标准Hib抗血清形成明显的沉淀线.结论 优化的Hib多糖纯化工艺具有较好的稳定性,且易于工艺放大,可替代传统工艺用于Hib多糖的纯化.%Objective To optimize the purification process of Haemophilus influenzae type b (Hib) polysaccharide for replacing the traditional combination of phenol and ethanol.Methods Crude Hib polysaccharides were extracted with Cetavlon and further purified with the combination of sodium deoxycholate and ethanol multistage purification,and purified polysaccharides were obtained by ultrafiltration and sterilizing filtration.Three batches of purified Hib polysaccharides were prepared with the optimized purification precess in pilot and other 3 batches in amplifying scales.Prepared Hib polysaccharides were detected in accordance with the Chinese Pharmacopoeia 2010 edition (Volume Ⅲ).Results The relative molecular masses of each 3 batches of Hib polysaccharides purified in pilot and amplifying scales were 621 800,634 400,659 900 and 597 200,612 100,583 400,respectively,and all met standard requirement.The contents of bacterial endotoxin of each 3 batches

  1. 香菇多糖抑菌作用的研究%Antimicrobial Characteristics of Polysaccharide from Ganoderma Lentinan

    Institute of Scientific and Technical Information of China (English)

    孟俊龙; 冯翠萍; 常明昌; 程红艳

    2012-01-01

    为研究香菇多糖对细菌的抑制作用,采用分光光度法研究香菇多糖对枯草芽孢杆菌(Bacillus subtilis)、大肠杆菌(Escherichia coli)、金黄色葡萄球菌(Staphylococcus aureus)、沙门氏菌(Salmonella)的抑制作用,并探讨作用时间和pH值对其抗菌活性的影响,以确定最佳抑菌时间和pH值.结果表明,香菇多糖对四种菌的抑制作用由强到弱依次为金黄色葡萄球菌、枯草芽孢杆菌、大肠杆菌、沙门氏菌.对沙门氏菌的抑制作用在24 h时达到最大,对其它3种菌均在12 h时达到最大.pH值对抑菌作用有一定的影响,对金黄色葡萄球菌的抑制作用在pH值为6时最大;对其它菌的抑制作用均在pH值为5时最大.%Spectrophotometry method was used to measure the anti-bacterial including Bacillus subtilis, Escherichia co-li, Staphylococcus aureus, Salmonella activities of polysaccharide from Ganoderm Lucidum. The effect of time and pH value on anti-bacterial activity was discussed, so as to determine the optimal anti-bacterial time and pH value. The results indicated that Ganoderma lucidum polysaccharide could inhibit Bacillus subtilis, Escherichia coli, Staphylococcus aureus, Salmonella, the order of inhibition was Bacillus subtilis, Staphylococcus aureus, Escherichia coli, Salmonella. The maximum inhibition activity on Salmonella was 24 h, the others was 12 h. The pH had some influences on anti-bacterial effect, The maximum inhibition activity on Salmonella was at pH 6, the others were at pH 5.

  2. Biological activities of a neutral water-soluble agar polysaccharide prepared by agarase degradation

    Institute of Scientific and Technical Information of China (English)

    Wang Jingxue; Mou Haijin; Jiang Xiaolu; Guan Huashi

    2005-01-01

    Depolymerization of agar was performed using agarase, which was extracted from the cell-free medium of a culture of marine bacterial Alteromonas sp. nov. SY 37-12. After ethanol fractionation and lyophilization, the water-soluble agar polysaccharide (WSAP3) was collected. The anti-tumor activity of the product was determined by using Sarcoma 180 tumor in mouse. The tumor inhibition rate of WSAP3 reached 48.7% at a dose of 64mg kg-1 after 15 days treatment. WSAP3 enhanced the activities of superoxide dismutase and catalase, which suggests that WSAP3 was effective in promoting the antioxidation ability and eliminating danger from free radicals. The result of flow cytometry showed that the WSAP3 had no activities of cell cycle inhibition or apoptosis-inducing activities. The anti-oxidation of WSAP3 was further confirmed by test in vitro, which might play an important role in anti-tumor activity. The immunological regulation of WSAP3, especially its effect on the phagocytosis ratio and phagocytosis index of macrophage was also assayed in test in vivo.

  3. Antimicrobial effect of a crude sulfated polysaccharide from the red seaweed Gracilaria ornata

    Directory of Open Access Journals (Sweden)

    Rodrigo das Neves dos Santos Amorim

    2012-04-01

    Full Text Available The aim of this study was to determine the yield, chemical composition, specific rotation (SR, infrared (IR spectroscopy and the effect on bacterial growth of a crude sulfated polysaccharide (SP from the red marine alga G. ornata (Go. Go-1 (25°C, Go-2 (80°C, and Go-3 (80°C were sequentially extracted and yielded 9.2%. The contents of sulfate (5.88-10.3% and proteins (0.1-3.7% were small. The values of SR were [µ]D20°f -19.0, -51.0, and -56.5, respectively. IR spectrums showed the presence of galactose-4 sulfate and absence of 3,6-anydrogalactose-2 sulfate, galactose-6 sulfate and galactose-2 sulfate. SR and IR techniques confirmed SPs. Go-3 was tested on the growth of bacteria (Bacillus subtilis, Staphylococcus aureus, Enterobacter aerogens, Escherichia coli, Pseudomonas aeruginosa, Salmonela choleraesuis and Salmonela typhi, but only E. coli was inhibited.

  4. Evidence for a role of the polysaccharide capsule transport proteins in pertussis pathogenesis.

    Directory of Open Access Journals (Sweden)

    Regina Hoo

    Full Text Available Polysaccharide (PS capsules are important virulence determinants for many bacterial pathogens. Bordetella pertussis, the agent of whooping cough, produces a surface associated microcapsule but its role in pertussis pathogenesis remained unknown. Here we showed that the B. pertussis capsule locus is expressed in vivo in murine lungs and that absence of the membrane-associated protein KpsT, involved in the transport of the PS polymers across the envelope, but not the surface-exposed PS capsule itself, affects drastically B. pertussis colonization efficacy in mice. Microarray analysis revealed that absence of KpsT in B. pertussis resulted in global down-regulation of gene expression including key virulence genes regulated by BvgA/S, the master two-component system. Using a BvgS phase-locked mutant, we demonstrated a functional link between KpsT and BvgA/S-mediated signal transduction. Whereas pull-down assays do not support physical interaction between BvgS sensor and any of the capsule locus encoded proteins, absence of KpsT impaired BvgS oligomerization, necessary for BvgS function. Furthermore, complementation studies indicated that instead of KpsT alone, the entire PS capsule transport machinery spanning the cell envelope likely plays a role in BvgS-mediated signal transduction. Our work thus provides the first experimental evidence of a role for a virulence-repressed gene in pertussis pathogenesis.

  5. Structural investigation of cell wall polysaccharides of Lactobacillus delbrueckii subsp. bulgaricus 17.

    Science.gov (United States)

    Vinogradov, E; Sadovskaya, I; Cornelissen, A; van Sinderen, D

    2015-09-01

    Lactobacilli are valuable strains for commercial (functional) food fermentations. Their cell surface-associated polysaccharides (sPSs) possess important functional properties, such as acting as receptors for bacteriophages (bacterial viruses), influencing autolytic characteristics and providing protection against antimicrobial peptides. The current report provides an elaborate molecular description of several surface carbohydrates of Lactobacillus delbrueckii subsp. bulgaricus strain 17. The cell surface of this strain was shown to contain short chain poly(glycerophosphate) teichoic acids and at least two different sPSs, designated here as sPS1 and sPS2, whose chemical structures were examined by 2D nuclear magnetic resonance spectroscopy and methylation analysis. Neutral branched sPS1, extracted with n-butanol, was shown to be composed of hexasaccharide repeating units (-[α-d-Glcp-(1-3)-]-4-β-l-Rhap2OAc-4-β-d-Glcp-[α-d-Galp-(1-3)]-4-α-Rhap-3-α-d-Galp-), while the major component of the TCA-extracted sPS2 was demonstrated to be a linear d-galactan with the repeating unit structure being (-[Gro-3P-(1-6)-]-3-β-Galf-3-α-Galp-2-β-Galf-6-β-Galf-3-β-Galp-).

  6. Extracellular polysaccharide of Erwinia chrysanthemi A350 and ribotyping of Erwinia chrysanthemi spp.

    Science.gov (United States)

    Gray, J S; Yang, B Y; Montgomery, R

    2000-03-10

    Erwinia chrysanthemi spp. are gram-negative bacterial phytopathogens causing soft rots in a number of plants. The structure of the extracellular polysaccharide (EPS) produced by the E. chrysanthemi strain A350, which is a lacZ- mutant of the wild type strain 3937, pathogenic to Saintpaulia, has been determined using a combination of chemical and physical techniques including methylation analysis, low-pressure gel-filtration and anion-exchange chromatography, high-pH anion-exchange chromatography, partial acid hydrolysis, mass spectrometry and 1- and 2D NMR spectroscopy. In contrast to the structures of the EPS reported for other strains of E. chrysanthemi, the EPS from strain A350 contains D-GalA, together with L-Rhap and D-Galp in a 1:4:1 ratio. Evidence is presented for the following hexasaccharide repeat unit: [structure: see text] All the Erwinia chrysanthemi spp. studied to date have been analyzed by ribotyping and collated into families, which are consistent with the related structures of their EPS. PMID:10744334

  7. Chemical characterization and immunomodulatory properties of polysaccharides isolated from probiotic Lactobacillus casei LOCK 0919

    Science.gov (United States)

    Górska, Sabina; Hermanova, Petra; Ciekot, Jarosław; Schwarzer, Martin; Srutkova, Dagmar; Brzozowska, Ewa; Kozakova, Hana; Gamian, Andrzej

    2016-01-01

    The Lactobacillus casei strain, LOCK 0919, is intended for the dietary management of food allergies and atopic dermatitis (LATOPIC® BIOMED). The use of a probiotic to modulate immune responses is an interesting strategy for solving imbalance problems of gut microflora that may lead to various disorders. However, the exact bacterial signaling mechanisms underlying such modulations are still far from being understood. Here, we investigated variations in the chemical compositions and immunomodulatory properties of the polysaccharides (PS), L919/A and L919/B, which are produced by L. casei LOCK 0919. By virtue of their chemical features, such PS can modulate the immune responses to third-party antigens. Our results revealed that L919/A and L919/B could both modulate the immune response to Lactobacillus planatarum WCFS1, but only L919/B could alter the response of THP-1 cells (in terms of tumor necrosis factor alpha production) to L. planatarum WCFS1 and Escherichia coli Nissle 1917. The comprehensive immunochemical characterization is crucial for the understanding of the biological function as well as of the bacteria–host and bacteria–bacteria cross-talk. PMID:27102285

  8. Bupleurum polysaccharides attenuates lipopolysaccharide-induced inflammation via modulating Toll-like receptor 4 signaling.

    Directory of Open Access Journals (Sweden)

    Jian Wu

    Full Text Available BACKGROUND: Bupleurum polysaccharides (BPs, isolated from Bupleurum smithii var. parvifolium, possesses immunomodulatory activity, particularly on inflammation. Bacterial endotoxin lipopolysaccharide (LPS triggers innate immune responses through Toll-like receptor 4 (TLR4 on host cell membrane. The present study was performed to evaluate whether the therapeutic efficacy of BPs on suppression of LPS's pathogenecity could be associated with the modulating of TLR4 signaling pathway. METHODOLOGY/PRINCIPAL FINDINGS: LPS stimulated expression and activation of factors in the TLR4 signaling system, including TLR4, CD14, IRAK4, TRAF6, NF-κB, and JNK, determined using immunocytochemical and/or Western blot assays. BPs significantly inhibited these effects of LPS. LPS increased pro-inflammatory cytokines (TNF-α, IL-6, IL-1β, IL-12p40, and IFN-β and NO production, evaluated using ELISA and Griess reaction assays, respectively. BPs antagonized these effects of LPS. Interestingly, BPs alone augmented secretion of some pro-inflammatory cytokines of non-LPS stimulated macrophages and enhanced phagocytic activity towards fluorescent E.coli bioparticles. In a rat model of acute lung injury (ALI with pulmonary hemorrhage and inflammation, BPs ameliorated lung injuries and suppressed TLR4 expression. SIGNIFICANCE: The therapeutic properties of BPs in alleviating inflammatory diseases could be attributed to its inhibitory effect on LPS-mediated TLR4 signaling.

  9. Modification of cell wall polysaccharides during retting of cassava roots.

    Science.gov (United States)

    Ngolong Ngea, Guillaume Legrand; Guillon, Fabienne; Essia Ngang, Jean Justin; Bonnin, Estelle; Bouchet, Brigitte; Saulnier, Luc

    2016-12-15

    Retting is an important step in traditional cassava processing that involves tissue softening of the roots to transform the cassava into flour and various food products. The tissue softening that occurs during retting was attributed to the degradation of cell wall pectins through the action of pectin-methylesterase and pectate-lyase that possibly originated from a microbial source or the cassava plant itself. Changes in cell wall composition were investigated during retting using chemical analysis, specific glycanase degradation and immuno-labelling of cell wall polysaccharides. Pectic 1,4-β-d-galactan was the main cell wall polysaccharide affected during the retting of cassava roots. This result suggested that better control of pectic galactan degradation and a better understanding of the degradation mechanism by endogenous endo-galactanase and/or exogenous microbial enzymes might contribute to improve the texture properties of cassava products. PMID:27451197

  10. Melissotarsus ants are likely able to digest plant polysaccharides.

    Science.gov (United States)

    Mony, Ruth; Dejean, Alain; Bilong, Charles Félix Bilong; Kenne, Martin; Rouland-Lefèvre, Corinne

    2013-10-01

    Melissotarsus ants have an extremely specialized set of behaviours. Both workers and gynes tunnel galleries in their host tree bark. Workers walk with their mesothoracic legs pointing upwards and tend Diaspididae hemiptera for their flesh. The ants use their forelegs to plug the galleries with silk that they secrete themselves. We hypothesised that the ants' energetic needs for nearly constant gallery digging could be satisfied through the absorption of host tree tissues; so, using basic techniques, we examined the digestive capacities of workers from two species. We show that workers are able to degrade oligosaccharides and heterosides as well as, to a lesser degree, polysaccharides. This is one of the rare reports on ants able to digest plant polysaccharides other than starch.

  11. Rheological characterization of levan polysaccharides from Microbacterium laevaniformans.

    Science.gov (United States)

    Bae, In Young; Oh, Im-Kyung; Lee, Suyong; Yoo, Sang-Ho; Lee, Hyeon Gyu

    2008-01-01

    Levan polysaccharides were produced from Microbacterium laevaniformans and its rheological behaviors were characterized as a function of concentration and temperature. The intrinsic viscosity of the purified levan was determined to be 0.38dL/g at 25 degrees C which was relatively higher than that of levans from other microbial sources. The flow behaviors of the levan solutions were characterized by the increase in the shear stress, giving more increments in the shear rate. Thus, the levan solutions exhibited the pseudoplastic behavior, which was characterized by the power law model. In addition, the flow behaviors of the levans were satisfactorily fitted to the Arrhenius equation where the activation energy of flow (Ea) decreased from 24.07 to 13.53kJ/mol (R2=0.98-0.99) with increasing concentrations. Moreover, the exponential equation was favorably applied to describe the effect of concentration on the apparent viscosity of the levan polysaccharides. PMID:17931701

  12. Results of the Study of Mutagenic Effects of Microbial Polysaccharides

    Directory of Open Access Journals (Sweden)

    Natalya A. Sidorova

    2016-06-01

    Full Text Available The article presents the results of a study of mutagenic effects of Pseudomonas alcaligenеs polysaccharides. Pseudomonas genus – non-fermentative ubiquitous bacteria, having specific metabolic cycles and unique physical, chemical and biological properties was used as a producer of natural exopolysaccharides. In an experiment using the Ames test, three variants of test compounds were studied: 1. a compound of the Pseudomonas alcaligenes biofilm, 2. exopolysaccharide matrix and the microorganism cell wall compound, and 3. actually the microbial exopolysaccharide. In all cases the lack of mutagen action of polysaccharides of Pseudomonas alcaligenes is proved that make them perspective for use as nanomaterials of new generation – alternative wound coverings.

  13. Tomato Derived Polysaccharides for Biotechnological Applications: Chemical and Biological Approaches

    Directory of Open Access Journals (Sweden)

    Barbara Nicolaus

    2008-06-01

    Full Text Available Recent studies concerning the isolation and purification of exopolysaccharides from suspension-cultured tomato (Lycopersicon esculentum L. var. San Marzano cells and the description of a simple, rapid and low environmental impact method with for obtaining polysaccharides from solid tomato-processing industry wastes are reported. Their chemical composition, rheological properties and partial primary structure were determined on the basis of spectroscopic analyses (UV, IR, GC-MS, 1H-, 13C-NMR. Moreover, the anticytotoxic activities of exopolysaccharides obtained from cultured tomato cells were tested in a brine shrimp bioassay and the preparation of biodegradable film by chemical processing of polysaccharides from solid tomato industry waste was also reported.

  14. Experience with Salmonella typhi Vi capsular polysaccharide vaccine.

    Science.gov (United States)

    Hessel, L; Debois, H; Fletcher, M; Dumas, R

    1999-09-01

    Typhoid fever remains an important health threat in many parts of the world, with an estimated 16 million cases and 600,000 deaths occurring each year. The emergence of Salmonella typhi strains multiply resistant to antibiotics has complicated the treatment of this disease. Field experience of 8 years shows that a vaccine composed of purified Vi capsular polysaccharide of Salmonella typhi, given as a single intramuscular or deep subcutaneous injection, has consistent immunogenicity and efficacy. Side effects, based on reports since 1989, are infrequent and mild. Furthermore, the Vi vaccine may be administered simultaneously with other common "travel" vaccines, at two different sites of injection, without affecting immunogenicity and tolerability. This review presents an update of the development and clinical experience with the Salmonella typhi Vi polysaccharide vaccine (Typhim Vi; Pasteur Mérieux Connaught, France).

  15. Extracellular Polysaccharides Produced by Yeasts and Yeast-Like Fungi

    Science.gov (United States)

    van Bogaert, Inge N. A.; de Maeseneire, Sofie L.; Vandamme, Erick J.

    Several yeasts and yeast-like fungi are known to produce extracellular polysaccharides. Most of these contain D-mannose, either alone or in combination with other sugars or phosphate. A large chemical and structural variability is found between yeast species and even among different strains. The types of polymers that are synthesized can be chemically characterized as mannans, glucans, phosphoman-nans, galactomannans, glucomannans and glucuronoxylomannans. Despite these differences, almost all of the yeast exopolysaccharides display some sort of biological activity. Some of them have already applications in chemistry, pharmacy, cosmetics or as probiotic. Furthermore, some yeast exopolysaccharides, such as pullulan, exhibit specific physico-chemical and rheological properties, making them useful in a wide range of technical applications. A survey is given here of the production, the characteristics and the application potential of currently well studied yeast extracellular polysaccharides.

  16. The pretreatment effects on the antioxidant activity of jujube polysaccharides

    Science.gov (United States)

    Qu, Chenling; Yu, Songcheng; Jin, Huali; Wang, Jinshui; Luo, Li

    2013-10-01

    Pretreatment is vital to keep the bioactivities of polysaccharides. In this paper, the effects of hot water, ultrasonic and microwave extraction, as well as the effects of protein and pigment removal steps, on the antioxidant activity of water soluble polysaccharides in jujube (WSPJ) were studied. Hydroxyl free radical (rad OH) scavenging activity was adopted to determine the antioxidant activity of WSPJ. The results showed that rad OH scavenging activity of WSPJ extracted by ultrasonic wave was higher than that extracted by hot water and by microwave. Furthermore, power parameter in both ultrasonic and microwave extraction affected the rad OH scavenging activity dramatically. On the other hand, Sevag reagent was better than trichloroacetic acid (TCA), TCA with 1-butanol (TCA-B) and hydrochloric acid for protein removal, and H2O2 was better than active carbon for pigment removal to keep the antioxidant activity of WSPJ.

  17. Mapping the polysaccharide degradation potential of Aspergillus niger

    DEFF Research Database (Denmark)

    Andersen, Mikael Rørdam; Giese, Malene; de Vries, Ronald P.;

    2012-01-01

    Background: The degradation of plant materials by enzymes is an industry of increasing importance. For sustainable production of second generation biofuels and other products of industrial biotechnology, efficient degradation of non-edible plant polysaccharides such as hemicellulose is required....... For each type of hemicellulose, a complex mixture of enzymes is required for complete conversion to fermentable monosaccharides. In plant-biomass degrading fungi, these enzymes are regulated and released by complex regulatory structures. In this study, we present a methodology for evaluating the potential...... of 188 genes coding for carbohydrate-active enzymes from Aspergillus niger, thus forming an analysis framework, which can be queried. Combination of this information network with gene expression analysis on mono-and polysaccharide substrates has allowed elucidation of concerted gene expression from...

  18. Extraction, purification and antioxidant activity of polysaccharides from bamboo leaves

    Institute of Scientific and Technical Information of China (English)

    GAO Ya-ni; TIAN Cheng-rui; ZHAO Li-li

    2012-01-01

    Ultrasonic extraction (UE) was employed for the extraction of bamboo leaf polysaccharides (BLP).The influential parameters of UE procedure including extraction time,ultrasonic power and solid/liquid ratio were optimized by orthogonal experiments.DEAE-cellulose column chromatography was applied to purify BLP and then the radical scavenging activity of BLP was also evaluated.Optimal extraction conditions were:extraction time of 15 min,ultrasonic power of 300 W,and solid/liquid ratio of 1:15.Four kinds of polysaccharides were obtained by DEAE-cellulose column chromatography; the maximum superoxide radical scavenging rate (20.4%) of BLP was inferior to that of vitamin C (Vc,the control) and the hydroxyl radical scavenging rate (50%) was equivalent to that of Vc.

  19. LIGHT SCATTERING OF POLYSACCHARIDE FROM LACQUER IN AQUEOUS SOLUTION

    Institute of Scientific and Technical Information of China (English)

    ZHANG Lina; DU Yumin; KUMANOTANI JU

    1989-01-01

    The polysaccharide having weight-average molecular weight Mw= 1. 09 × 105 , isolated from the sap of lac trees ( Vietnam ), was separated into 12 fractions by aqueous-phase preparative gel permeation chromatography. The molecular weights and molecular weight distributions of the fractions were measured in aqueous 0.08M KCl/0.01 M NaAc and 0.4M KCl/0.05M NaAc at pH = 7.6 by light scattering, viscometry and gel permeation chromatography. The Mark-Houwink equation in aqueous 0.08M KCl/0.01M NaAc at30 ℃ was found to be [ η] = 2.28 ×10-2 M0.52w ( cm3/g ), which indicated the polysaccharide chain in the aqueous solution to be a spherical random coil.

  20. Effect of Extraction Methods on Polysaccharide of Clitocybe maxima Stipe

    OpenAIRE

    Junchen Chen; Pufu Lai; Hengsheng Shen; Hengguang Zhen; Rutao Fang

    2013-01-01

    Clitocybe maxima (Gartn. ex Mey. Fr.) Quél. is a favorable edible fungi species. The proportion of its stipe is about 45% of entire fruit biomass, which is a low value defined byproduct. To increase its value added utilization, three extraction methods (as hot water, microwave-assisted and complex-enzyme-hydrolysis-assist) were conducted. The extraction effect on the polysaccharide of Clitocybe maxima stipe was compared and the processing conditions in extraction were optimized. The content o...

  1. Size-exclusion chromatography (SEC) of branched polymers and polysaccharides

    OpenAIRE

    Gaborieau, Marianne; Castignolles, Patrice

    2010-01-01

    Branched polymers are among the most important polymers, ranging from polyolefins to polysaccharides. Branching plays a key role in the chain dynamics. It is thus very important for application properties such as mechanical and adhesive properties and digestibility. It also plays a key role in viscous properties, and thus in the mechanism of the separation of these polymers in size-exclusion chromatography (SEC). Critically reviewing the literature, particularly on SEC of polyolefins, polyacr...

  2. Hydrolysis of Polysaccharides with 77% Sulfuric Acid for Quantitative Saccharification

    OpenAIRE

    UÇAR, Güneş; Balaban, Mualla

    2003-01-01

    Classical standard hydrolysis of polysaccharides with 72% sulfuric acid was modified in 2 manners. In order to avoid treatment in an autoclave at 120 °C under pressure, wood or pulp material was first swollen in cold 77% acid followed by hydrolysis steps in diluted acid solutions. Further, the neutralization of the hydrolyzate with dilute barium hydroxide was carried out in heated mother liquor ensuring a crystalline precipitate of barium sulfate. Digestion enables the separation of clear ali...

  3. Metabolic engineering of microbes for oligosaccharide and polysaccharide synthesis

    OpenAIRE

    Chen Rachel; Ruffing Anne

    2006-01-01

    Abstract Metabolic engineering has recently been embraced as an effective tool for developing whole-cell biocatalysts for oligosaccharide and polysaccharide synthesis. Microbial catalysts now provide a practical means to derive many valuable oligosaccharides, previously inaccessible through other methods, in sufficient quantities to support research and clinical applications. The synthesis process based upon these microbes is scalable as it avoids expensive starting materials. Most impressive...

  4. Pneumococcal vaccination of older adults: Conjugate or polysaccharide?

    OpenAIRE

    Fedson, David S; Guppy, Martin J.

    2013-01-01

    Invasive pneumococcal disease continues to be important problem for older adults. Pneumococcal polysaccharide vaccine (PPV23) has a clinical effectiveness of 43–81%, and following primary vaccination and revaccination, antibody responses last 5–10 y. Hyporesponsiveness to a second dose of vaccine has not been shown to be a significant problem. The use of pneumococcal conjugate vaccines (initially PCV7; more recently PCV13) has led to a dramatic fall in the incidence of conjugate vaccine-type ...

  5. Complete structure of the polysaccharide from Streptococcus sanguis J22

    Energy Technology Data Exchange (ETDEWEB)

    Abeygunawardana, C.; Bush, C.A. (Illinois Institute of Technology, Chicago (USA)); Cisar, J.O. (National Institute of Dental Research, Bethesda, MD (USA))

    1990-01-09

    The cell wall polysaccharides of certain oral streptococci such as Streptococcus sanguis strains 34 and J22, although immunologically distinct, act as receptors for the fimbrial lectins of Actinomyces viscosus T14V. The authors report the complete covalent structure of the polysaccharide from S. sanguis J22 which is composed of a heptasaccharide subunit linked by phosphodiester bonds. The repeating subunit, which contains {alpha}-GalNAc, {alpha}-rhamnose, {beta}-rhamnose, {beta}-glucose, and {beta}-galactose all in the pyranoside form and {beta}-galactofuranose, is compared with the previously published structure of the polysaccharide from strain 34. The structure has been determined almost exclusively by high-resolution nuclear magnetic resonance methods. The {sup 1}H and {sup 13}C NMR spectra of the polysaccharides from both strains 34 and J22 have been completely assigned. The stereochemistry of pyranosides was assigned from J{sub H-H} values determined from phase-sensitive COSY spectra, and acetamido sugars were assigned by correlation of the resonances of the amide {sup 1}H with the sugar ring protons. The {sup 13}C spectra were assigned by {sup 1}H-detected multiple-quantum correlation (HMQC) spectra, and the assignments were confirmed by {sup 1}H-detected multiple-bond correlation (HMBC) spectra. The positions of the glycosidic linkages were assigned by detection of three-bond {sup 1}H-{sup 13}C correlation across the glycosidic linkage in the HMBC spectra. The positions of the phosphodiester linkages were determined by splittings observed in the {sup 13}C resonances due to {sup 31}P coupling and also by {sup 1}H-detected {sup 31}P correlation spectroscopy.

  6. Complex polysaccharides as PCR inhibitors in feces: Helicobacter pylori model.

    OpenAIRE

    Monteiro, L; Bonnemaison, D; Vekris, A. (A.); Petry, K G; Bonnet, J; Vidal, R.; Cabrita, J; Mégraud, F.

    1997-01-01

    A model was developed to study inhibitors present in feces which prevent the use of PCR for the detection of Helicobacter pylori. A DNA fragment amplified with the same primers as H. pylori was used to spike samples before extraction by a modified QIAamp tissue method. Inhibitors, separated on an Ultrogel AcA44 column, were characterized. Inhibitors in feces are complex polysaccharides possibly originating from vegetable material in the diet.

  7. Complex polysaccharides as PCR inhibitors in feces: Helicobacter pylori model.

    Science.gov (United States)

    Monteiro, L; Bonnemaison, D; Vekris, A; Petry, K G; Bonnet, J; Vidal, R; Cabrita, J; Mégraud, F

    1997-04-01

    A model was developed to study inhibitors present in feces which prevent the use of PCR for the detection of Helicobacter pylori. A DNA fragment amplified with the same primers as H. pylori was used to spike samples before extraction by a modified QIAamp tissue method. Inhibitors, separated on an Ultrogel AcA44 column, were characterized. Inhibitors in feces are complex polysaccharides possibly originating from vegetable material in the diet. PMID:9157172

  8. INFLUENCE OF SOLUBLE POLYSACCHARIDE ON THE ADHERENCE OF PARTICULATE SOILS

    OpenAIRE

    Toure, Yetioman; Rouxhet, Paul G.; Dupont-Gillain, C. Christine; Sindic, Marianne

    2011-01-01

    The removal of particulate soils from solid surfaces is the key process of cleaning many industrial devices, such as heat exchangers and spray dryers (food and pharmaceutical sector), and may be influenced by the presence of solutes, in particular of macromolecules. The present study deals with the influence of soluble polysaccharide on the adherence of particulate fouling of open surfaces and on subsequent cleaning. Model substrates differing by hydrophobicity (glass and polystyrene) were so...

  9. INFLUENCE OF SOLUBLE POLYSACCHARIDE ON THE ADHERENCE OF PARTICULATE SOILS

    OpenAIRE

    Toure, Yetioman; Rouxhet, G. Paul; Dupont-Gillain, C. Christine; Sindic, Marianne

    2011-01-01

    The removal of particulate soils from solid surfaces is the key process of cleaning many industrial devices, such as heat exchangers and spray dryers (food and pharmaceutical sector), and may be influenced by the presence of solutes, in particular of macromolecules. The present study deals with the influence of soluble polysaccharide on the adherence of particulate fouling of open surfaces and on subsequent cleaning. Model surfaces differing by hydrophobicity (glass and polystyrene) were soil...

  10. High molecular weight polysaccharide that binds and inhibits virus

    Science.gov (United States)

    Konowalchuk, Thomas W

    2014-01-14

    This invention provides a high molecular weight polysaccharide capable of binding to and inhibiting virus and related pharmaceutical formulations and methods on inhibiting viral infectivity and/or pathogenicity, as well as immunogenic compositions. The invention further methods of inhibiting the growth of cancer cells and of ameliorating a symptom of aging. Additionally, the invention provides methods of detecting and/or quantifying and/or isolating viruses.

  11. Affinity purification of polysaccharide degrading enzymes with crosslinked substrates.

    OpenAIRE

    Rozie, H.J.

    1992-01-01

    The aim of this work was to find economically favourable, affinity based, purification methods for several polysaccharide splitting bulk enzymes. The framework in which this study is done is described in Chapter 1.Chapter 2 describes the adsorption of endo-polygalacturonase (endoPG) from a commercial enzyme preparation (Rapidase) to calcium alginate beads. Approximately 75% of the various polygalacturonase activities from Rapidase can be adsorbed at pH 4.4 by calcium alginate beads as well as...

  12. Effects of Ganoderma lucidum polysaccharides on diabetic nephropathy in mice

    Institute of Scientific and Technical Information of China (English)

    Chao-yongHE; Zhi-binLIN

    2004-01-01

    AIM: To study the effects of Ganoderma lucidum polysaccharides (GL-PS) on the renal damage in streptozotocin-induced diabetic mice. METHODES: Nine weeks old male C57 BI/6J mice were made diabetes with two or three consecutive intraperitoneal injection of streptozotocin, 72 h later, hyperglycemic mice with glucose levels higher than glucose 300 mg/dL were used. The diabetic mice were randomly divided into three groups and administrated intragastrically with vehicle or Gl-PS (125 mg/

  13. Antibiofilm Activity of Actinobacillus pleuropneumoniae Serotype 5 Capsular Polysaccharide

    OpenAIRE

    Karwacki, Michael T.; Kadouri, Daniel E; Meriem Bendaoud; Izano, Era A.; Vandana Sampathkumar; Inzana, Thomas J.; Kaplan, Jeffrey B.

    2013-01-01

    Cell-free extracts isolated from colony biofilms of Actinobacillus pleuropneumoniae serotype 5 were found to inhibit biofilm formation by Staphylococcus aureus, S. epidermidis and Aggregatibacter actinomycetemcomitans, but not by A. pleuropneumoniae serotype 5 itself, in a 96-well microtiter plate assay. Physical and chemical analyses indicated that the antibiofilm activity in the extract was due to high-molecular-weight polysaccharide. Extracts isolated from a mutant strain deficient in the ...

  14. Polysaccharides as Alternative Moisture Retention Agents for Shrimp.

    Science.gov (United States)

    Torti, Michael J; Sims, Charles A; Adams, Charles M; Sarnoski, Paul J

    2016-03-01

    Phosphates are used as moisture retention agents (MRAs) by the shrimp industry. Although they are effective, phosphates are expensive, need to be listed on a food label, and overuse can often lead to a higher product cost for consumers. Polysaccharides were researched as alternative MRAs. Polysaccharides are usually inexpensive, are considered natural, and can have nutritional benefits. Research was conducted to determine whether polysaccharides yielded similar functional impacts as phosphates. Treatments included a 0.5% fibercolloid solution isolated from citrus peel, an 8% pectin solution, a 0.5% xanthan gum (XG) solution, a 1% carboxymethyl cellulose solution, and conventionally used 4% sodium tripolyphosphate (STP). Experimental treatments were compared to a distilled water control to gauge effectiveness. Freezing, boiling, and oven drying studies were performed to determine how moisture retention in shrimp differed using these different treatments. Water activity was measured to determine any potential differences in shelf life. Solution uptake was also determined to understand how well the treatments enhanced water binding. For moisture loss by freezing, 4% STP and the 0.5% fibercolloid solution functioned the best. The 4% STP treated shrimp lost the least amount of moisture during boiling. The 0.5% fibercolloid and 0.5% XG treatment outperformed phosphates in respect to moisture uptake ability. None of the treatments had a major effect on water activity. All treatments were rated similar in consumer sensory acceptability tests except for pectin, which was rated lower by the sensory panel. Overall, polysaccharides were found to be viable alternatives to phosphates. PMID:26849189

  15. The bacterial lipocalins.

    Science.gov (United States)

    Bishop, R E

    2000-10-18

    The lipocalins were once regarded as a eukaryotic protein family, but new members have been recently discovered in bacteria. The first bacterial lipocalin (Blc) was identified in Escherichia coli as an outer membrane lipoprotein expressed under conditions of environmental stress. Blc is distinguished from most lipocalins by the absence of intramolecular disulfide bonds, but the presence of a membrane anchor is shared with two of its closest homologues, apolipoprotein D and lazarillo. Several common features of the membrane-anchored lipocalins suggest that each may play an important role in membrane biogenesis and repair. Additionally, Blc proteins are implicated in the dissemination of antibiotic resistance genes and in the activation of immunity. Recent genome sequencing efforts reveal the existence of at least 20 bacterial lipocalins. The lipocalins appear to have originated in Gram-negative bacteria and were probably transferred horizontally to eukaryotes from the endosymbiotic alpha-proteobacterial ancestor of the mitochondrion. The genome sequences also reveal that some bacterial lipocalins exhibit disulfide bonds and alternative modes of subcellular localization, which include targeting to the periplasmic space, the cytoplasmic membrane, and the cytosol. The relationships between bacterial lipocalin structure and function further illuminate the common biochemistry of bacterial and eukaryotic cells.

  16. [Antitumor Activity of Polysaccharides from Ganoderma lucidum Mycelium: in vivo Comparative Study].

    Science.gov (United States)

    Krasnopolskaya, L M; Yarina, M S; Avtonomova, A V; Usov, A I; Isakova, E B; Bukchman, V M

    2015-01-01

    Fractions of water soluble and alkali soluble polysaccharides, as well as fucogalactan, a water soluble polysaccharide, and xylomannan, an alkali soluble polysaccharide, were isolated from the Ganoderma lucidum submerged mycelium. When administered orally, the polysaccharides showed antitumor activity in vivo on murine models of solid tumors. Xylomannan and fucogalactan showed the highest antitumor activity. Sensitivity to xylomannan was more pronounced in adenocarcinoma Ca755 as compared to the T-cell lymphocytic leukemia P388. The antitumor activity of the water soluble polysaccharides total fractions from the mycelium and fruiting bodies of the G. lucidum strain was almost identical. The maximum antitumor effect of the mycelium water soluble polysaccharides total fraction was observed with the use of the daily dose of 2 mg/kg.

  17. Thermal stress resistance and aging effects of Panax notoginseng polysaccharides on Caenorhabditis elegans.

    Science.gov (United States)

    Feng, Shiling; Cheng, Haoran; Xu, Zhou; Shen, Shian; Yuan, Ming; Liu, Jing; Ding, Chunbang

    2015-11-01

    Panax notoginseng attract public attention due to their potential biomedical properties and corresponding health benefits. The present study investigated the anti-aging and thermal stress resistance effects of polysaccharides from P. notoginseng on Caenorhabditis elegans. Results showed polysaccharides had little scavenging ability of reactive oxygen species (ROS) in vitro, but significantly extended lifespan of C. elegans, especially the main root polysaccharide (MRP) which prolongs the mean lifespan of wild type worms by 21%. Further study demonstrated that the heat stress resistance effect of polysaccharides on C. elegans might be attributed to the elevation of antioxidant enzyme activities (both superoxide dismutase (SOD) and catalase (CAT)) and the reduction lipid peroxidation of malondialdehyde (MDA) level. Taken together, the results provided a scientific basis for the further exploitation of the mechanism of longer lifespan controlled by P. notoginseng polysaccharides on C. elegans. The P. notoginseng polysaccharides might be considered as a potential source to delay aging.

  18. Translational Medicine Study on Extraction and Determination of Urtica Polysaccharides and Their Anti-Oxidation Effect

    Institute of Scientific and Technical Information of China (English)

    JIANG Zhi-tao; LI Shan-shan; WANG Tong-fang; CHEN Xiao-feng

    2016-01-01

    Objective: Translational medicine study on extraction and determination of urtica polysaccharides and their anti-oxidation effect. Methods: Water-soluble alcohol sedimentation technique was used to extract the urtica polysaccharides, and ultraviolet (UV) spectrophotometry was applied to determine their content. The influence of polysaccharides on the activities of glutathione (GSH), catalase (CAT), malondialdéhyde (MDA) and superoxyde dismutase (SOD) in mice with H22-loaded tumors was observed. Results: The purity of urtica polysaccharides was 61.39% after extraction and puriifcation. After administration of high-, moderate- and low-dose urtica polysaccharides, the activity of serum GSH, CAT and SOD was markedly higher while MDA content was prominently lower in mice with H22-loaded tumors than those in model group. Conclusion: Urtica polysaccharides can strengthen the anti-oxidation effect and inhibit the lipid peroxidation reaction in body.

  19. Polysaccharide-coated PCL nanofibers for wound dressing applications.

    Science.gov (United States)

    Croisier, Florence; Atanasova, Ganka; Poumay, Yves; Jérôme, Christine

    2014-12-01

    Polysaccharide-based nanofibers with a multilayered structure are prepared by combining electrospinning (ESP) and layer-by-layer (LBL) deposition techniques. Charged nanofibers are firstly prepared by electrospinning poly(ε-caprolactone) (PCL) with a block-copolymer bearing carboxylic acid functions. After deprotonation of the acid groups, the layer-by-layer deposition of polyelectrolyte polysaccharides, notably chitosan and hyaluronic acid, is used to coat the electrospun fibers. A multilayered structure is achieved by alternating the deposition of the positively charged chitosan with the deposition of a negatively charged polyelectrolyte. The construction of this multilayered structure is followed by Zeta potential measurements, and confirmed by observation of hollow nanofibers resulting from the dissolution of the PCL core in a selective solvent. These novel polysaccharide-coated PCL fiber mats remarkably combine the mechanical resistance typical of the core material (PCL)-particularly in the hydrated state-with the surface properties of chitosan. The control of the nanofiber structure offered by the electrospinning technology, makes the developed process very promising to precisely design biomaterials for tissue engineering. Preliminary cell culture tests corroborate the potential use of such system in wound healing applications. PMID:25263074

  20. Thermal analysis of some natural polysaccharide materials by isoconversional method.

    Science.gov (United States)

    Iqbal, Mohammad S; Massey, Shazma; Akbar, Jamshed; Ashraf, Chaudhary M; Masih, Rashid

    2013-09-01

    Isoconversional thermal analysis of some important polysaccharides from functional foods is reported. Various thermal parameters including apparent activation energy (Ea), pre-exponential factor (A) were worked out, and the fitness of data to different models describing the degradation kinetics of polysaccharides was studied. The polysaccharides from Mimosa pudica (MP), Plantago ovata (PO), Argyreia speciosa (AS), Acacia nilotica (AN), P. ovata husk (HK) and Acacia modesta (AM) exhibited multistep degradation while those from Astragalus gummifer (AG), Salvia aegyptiaca (SA) and Ocimum basicilicum (OB) degraded mainly in single step. Generally, the degradation was exothermal. The average Ea values as determined by Flynn-Wall-Ozawa method were found to be in the range 132-187 kJ mol(-1). The mean comprehensive index of thermal stability (ITS) fell in the range 0.33-0.43. All the materials under investigation except those from SA and AS appear to be as stable as some of the important commercial materials used as pharmaceutical ingredients. Model-fitting analysis revealed that the major degradation step follows first-order kinetics. PMID:23578630

  1. Recombinant expression of Streptococcus pneumoniae capsular polysaccharides in Escherichia coli

    Science.gov (United States)

    Kay, Emily J.; Yates, Laura E.; Terra, Vanessa S.; Cuccui, Jon; Wren, Brendan W.

    2016-01-01

    Currently, Streptococcus pneumoniae is responsible for over 14 million cases of pneumonia worldwide annually, and over 1 million deaths, the majority of them children. The major determinant for pathogenesis is a polysaccharide capsule that is variable and is used to distinguish strains based on their serotype. The capsule forms the basis of the pneumococcal polysaccharide vaccine (PPV23) that contains purified capsular polysaccharide from 23 serotypes, and the pneumococcal conjugate vaccine (PCV13), containing 13 common serotypes conjugated to CRM197 (mutant diphtheria toxin). Purified capsule from S. pneumoniae is required for pneumococcal conjugate vaccine production, and costs can be prohibitively high, limiting accessibility of the vaccine in low-income countries. In this study, we demonstrate the recombinant expression of the capsule-encoding locus from four different serotypes of S. pneumoniae within Escherichia coli. Furthermore, we attempt to identify the minimum set of genes necessary to reliably and efficiently express these capsules heterologously. These E. coli strains could be used to produce a supply of S. pneumoniae serotype-specific capsules without the need to culture pathogenic bacteria. Additionally, these strains could be applied to synthetic glycobiological applications: recombinant vaccine production using E. coli outer membrane vesicles or coupling to proteins using protein glycan coupling technology. PMID:27110302

  2. Antioxidative properties of crude polysaccharides from Inonotus obliquus.

    Science.gov (United States)

    Mu, Haibo; Zhang, Amin; Zhang, Wuxia; Cui, Guoting; Wang, Shunchun; Duan, Jinyou

    2012-01-01

    The mushroom Inonotus obliquus has been widely used as a folk medicine in Russia, Poland and most of the Baltic countries. In this study, water-soluble and alkali-soluble crude polysaccharides (IOW and IOA) were isolated from I. obliquus, and the carbohydrate-rich fractions IOW-1 and IOA-1 were obtained respectively after deproteination and depigmentation. Their contents, such as neutral carbohydrate, uronic acid and protein, were measured. Their antioxidant properties against chemicals-induced reactive species (ROS) including 1,1'-Diphenyl-2-picrylhydrazyl (DPPH) radical, hydroxyl radical and superoxide anion radical, as well as their protective effects on H(2)O(2)-induced PC12 cell death were investigated. Results showed that I. obliquus polysaccharides can scavenge all ROS tested above in a dose-dependent manner. IOA and its product IOA-1 could rescue PC12 cell viability from 38.6% to 79.8% and 83.0% at a concentration of 20μg/mL. Similarly, IOW and its product IOW-1 at the same dose, can also increase cell viability to 84.9% and 88.6% respectively. The antioxidative activities of water-soluble and alkali-soluble polysaccharide constituents from I. obliquus might contribute to diverse medicinal and nutritional values of this mushroom. PMID:22942760

  3. Tamarind seed polysaccharide: A promising natural excipient for pharmaceuticals

    Directory of Open Access Journals (Sweden)

    Joshny Joseph

    2012-01-01

    Full Text Available The natural polymers always have exceptional properties which make them distinct from the synthetic polymers and tamarind seed polysaccharide (TSP is one such example which shows more valuable properties making it a useful excipient for a wide range of applications. TSP is a natural polysaccharide obtained from the seeds of Tamarindus indica, recently gaining a wide potential in the field of pharmaceutical and cosmetic industries. Its isolation and characterisation involve simple techniques resulting in cost-effective yield in its production. TSP shows uniqueness in its high drug holding capacity, high swelling index and high thermal stability, especially necessary for various novel drug delivery systems. It also plays the role of stabiliser, thickener, binder, release retardant, modifier, suspending agent, viscosity enhancer, emulsifying agent, as a carrier for novel drug delivery systems in oral, buccal, colon, ocular systems, nanofabrication, wound dressing and is also becoming an important part of food, cosmetics, confectionery and bakery. Various studies and experiments have been carried out to prove its multi-functional potentiality, from which it can be concluded that TSP can be a promising natural polysaccharide having enormous applications. This review focuses on the diversity of applications of TSP.

  4. Structure versus anticoagulant and antithrombotic actions of marine sulfated polysaccharides

    Directory of Open Access Journals (Sweden)

    Vitor Hugo Pomin

    2012-08-01

    Full Text Available Marine sulfated polysaccharides (MSP, such as sulfated fucans (SF, sulfated galactans (SG and glycosaminoglycans (GAG isolated from either algae or invertebrate animals, are highly anionic polysaccharides capable of interacting with certain cationic proteins, such as (co-factors of the coagulation cascade during clotting-inhibition processes. These molecular complexes between MSP and coagulation-related proteins might, at first glance, be assumed to be driven mostly by electrostatic interactions. However, a systematic comparison using several novel sulfated polysaccharides composed of repetitive oligosaccharides with clear sulfation patterns has shown that these molecular interactions are regulated essentially by the stereochemistry of the glycans (which depends on a conjunction of anomericity, monosaccharide, conformational preference, and glycosylation and sulfation sites, rather than just a simple consequence of their negative charge density (mainly the number of sulfate groups. Here, we present an overview of the structure-function relationships of MSP, correlating their structures with their potential anticoagulant and antithrombotic actions, since pathologies related to the cardiovascular system are one of the major causes of illness and mortality in the world.

  5. Influence of a cationic polysaccharide on starch functionality.

    Science.gov (United States)

    Raguzzoni, Josiane C; Delgadillo, Ivonne; Lopes da Silva, José A

    2016-10-01

    Fundamental rheology, differential scanning calorimetry and infrared spectroscopy have been used to evaluate the effect of a cationic polysaccharide, chitosan, on the gelatinization, gel formation and retrogradation of maize starch samples, under acidic aqueous conditions. Moderate acidic conditions (0.1molL(-1) acetic acid) have shown a (slight) positive effect on starch gelatinization process and structure development. The presence of chitosan increased the DSC onset gelatinization temperature and also shifted the onset of the storage modulus increase to higher temperatures. Formation of the starch gel, mainly gelation of the leached-out amylose, is somehow hindered by the presence of the cationic polysaccharide and, therefore, the retrogradation of starch at very early stage can be delayed by addition of chitosan. However, long-term retrogradation was slightly increased. FTIR pectroscopy did not reveal any significant interaction between both polysaccharides what is in accordance with the observed rheological behavior. Small additions of chitosan to starch-rich systems may be a useful strategy to obtain new textures with novel phase transition behaviors. PMID:27312647

  6. Characterization of diferuloylated pectic polysaccharides from quinoa (Chenopodium quinoa WILLD.).

    Science.gov (United States)

    Wefers, Daniel; Gmeiner, Bianca M; Tyl, Catrin E; Bunzel, Mirko

    2015-08-01

    In plants belonging to the order of Caryophyllales, pectic neutral side chains can be substituted with ferulic acid. The ability of ferulic acid to form intra- and/or intermolecular polysaccharide cross-links by dimerization was shown by the isolation and characterization of diferulic acid oligosaccharides from monocotyledonous plants. In this study, two diferulic acid oligosaccharides were isolated from the enzymatic hydrolyzate of seeds of the dicotyledonous pseudocereal quinoa by gel permeation chromatography and preparative HPLC and unambiguously identified by LC-MS(2) and 1D/2D NMR spectroscopy. The isolated oligosaccharides are comprised of 5-5- and 8-O-4-diferulic acid linked to the O2-position of the nonreducing residue of two (1→5)-linked arabinobioses. To get insight into the structure and the degree of phenolic acid substitution of the diferuloylated polysaccharides, polymeric sugar composition, glycosidic linkages, and polysaccharide-bound monomeric phenolic acids and diferulic acids were analyzed. This study demonstrates that diferulic acids are involved into intramolecular and/or intermolecular cross-linking of arabinan chains and may have a major impact on cell wall architecture of quinoa and other dicotyledonous plants of the order of Caryophyllales. PMID:25983037

  7. Influence of Temperature on the Extractibility of Polysaccharides in Barley

    Directory of Open Access Journals (Sweden)

    Rodica Căpriţă

    2011-10-01

    Full Text Available Barley contains substantial amounts of both soluble and insoluble non-starch polysaccharides (NSP. The main watersoluble NSP in barley are highly viscous β-glucans. Monogastric animals, including humans and birds, cannotsynthesize β-glucanase, and the amount of β-glucanase derived from barley grain and bacteria in the gastrointestinaltract is insufficient to completely hydrolyze β-glucans. In the present investigation, we have studied the influence oftemperature and heating time on the extractibility of soluble polysaccharides in barley. Heating the barley samples at60°C and 80°C before extraction has the effect of lowering the soluble fraction of the polysaccharides. The dynamicviscosity values of water extracts from barley decreased up to 21.68% when heating at 60ºC for 15 minutes, and upto 25.30% when heating at 80ºC for 15 minutes, when the determinations were made immediately after extractseparation. Heating the barley samples for 15 minutes at 80°C deactivates the endogenous hydrolytic enzymes.

  8. Purification, Characterization and Biological Activity of Polysaccharides from Dendrobium officinale

    Directory of Open Access Journals (Sweden)

    Kaiwei Huang

    2016-05-01

    Full Text Available Polysaccharide (DOPA from the stem of D. officinale, as well as two fractions (DOPA-1 and DOPA-2 of it, were isolated and purified by DEAE cellulose-52 and Sephacryl S-300 chromatography, and their structural characteristics and bioactivities were investigated. The average molecular weights of DOPA-1 and DOPA-2 were 394 kDa and 362 kDa, respectively. They were mainly composed of d-mannose, d-glucose, and had a backbone consisting of 1,4-linked β-d-Manp and 1,4-linked β-d-Glcp with O-acetyl groups. Bioactivity studies indicated that both DOPA and its purified fractions (DOPA-1 and DOPA-2 could activate splenocytes and macrophages. The D. officinale polysaccharides had stimulatory effects on splenocytes, T-lymphocytes and B-lymphocytes, promoting the cell viability and NO production of RAW 264.7 macrophages. Furthermore, DOPA, DOPA-1 and DOPA-2 were found to protect RAW 264.7 macrophages against hydrogen peroxide (H2O2-induced oxidative injury by promoting cell viability, suppressing apoptosis and ameliorating oxidative lesions. These results suggested that D. officinale polysaccharides possessed antioxidant activity and mild immunostimulatory activity.

  9. Purification, Characterization and Biological Activity of Polysaccharides from Dendrobium officinale.

    Science.gov (United States)

    Huang, Kaiwei; Li, Yunrong; Tao, Shengchang; Wei, Gang; Huang, Yuechun; Chen, Dongfeng; Wu, Chengfeng

    2016-01-01

    Polysaccharide (DOPA) from the stem of D. officinale, as well as two fractions (DOPA-1 and DOPA-2) of it, were isolated and purified by DEAE cellulose-52 and Sephacryl S-300 chromatography, and their structural characteristics and bioactivities were investigated. The average molecular weights of DOPA-1 and DOPA-2 were 394 kDa and 362 kDa, respectively. They were mainly composed of d-mannose, d-glucose, and had a backbone consisting of 1,4-linked β-d-Manp and 1,4-linked β-d-Glcp with O-acetyl groups. Bioactivity studies indicated that both DOPA and its purified fractions (DOPA-1 and DOPA-2) could activate splenocytes and macrophages. The D. officinale polysaccharides had stimulatory effects on splenocytes, T-lymphocytes and B-lymphocytes, promoting the cell viability and NO production of RAW 264.7 macrophages. Furthermore, DOPA, DOPA-1 and DOPA-2 were found to protect RAW 264.7 macrophages against hydrogen peroxide (H₂O₂)-induced oxidative injury by promoting cell viability, suppressing apoptosis and ameliorating oxidative lesions. These results suggested that D. officinale polysaccharides possessed antioxidant activity and mild immunostimulatory activity. PMID:27248989

  10. Immunomodulatory activity and partial characterisation of polysaccharides from Momordica charantia.

    Science.gov (United States)

    Deng, Yuan-Yuan; Yi, Yang; Zhang, Li-Fang; Zhang, Rui-Fen; Zhang, Yan; Wei, Zhen-Cheng; Tang, Xiao-Jun; Zhang, Ming-Wei

    2014-01-01

    Momordica charantia Linn. is used as an edible and medicinal vegetable in sub-tropical areas. Until now, studies on its composition and related activities have been confined to compounds of low molecular mass, and no data have been reported concerning the plant's polysaccharides. In this work, a crude polysaccharide of M. charantia (MCP) fruit was isolated by hot water extraction and then purified using DEAE-52 cellulose anion-exchange chromatography to produce two main fractions MCP1 and MCP2. The immunomodulatory effects and physicochemical characteristics of these fractions were investigated in vitro and in vivo. The results showed that intragastric administration of 150 or 300 mg·kg-·d⁻¹ of MCP significantly increased the carbolic particle clearance index, serum haemolysin production, spleen index, thymus index and NK cell cytotoxicity to normal control levels in cyclophosphamide (Cy)-induced immunosuppressed mice. Both MCP1 and MCP2 effectively stimulated normal and concanavalin A-induced splenic lymphocyte proliferation in vitro at various doses. The average molecular weights of MCP1 and MCP2, which were measured using high-performance gel permeation chromatography, were 8.55×10⁴ Da and 4.41×10⁵ Da, respectively. Both fractions exhibited characteristic polysaccharide bands in their Fourier transform infrared spectrum. MCP1 is mainly composed of glucose and galactose, and MCP2 is mainly composed of glucose, mannose and galactose. The results indicate that MCP and its fractions have good potential as immunotherapeutic adjuvants. PMID:25178064

  11. Polysaccharide extraction from Sphallerocarpus gracilis roots by response surface methodology.

    Science.gov (United States)

    Ma, Tingting; Sun, Xiangyu; Tian, Chengrui; Luo, Jiyang; Zheng, Cuiping; Zhan, Jicheng

    2016-07-01

    The extraction process of Sphallerocarpus gracilis root polysaccharides (SGRP) was optimized using response surface methodology with two methods [hot-water extraction (HWE) and ultrasonic-assisted extraction (UAE)]. The antioxidant activities of SGRP were determined, and the structural features of the untreated materials (HWE residue and UAE residue) and the extracted polysaccharides were compared by scanning electron microscopy. Results showed that the optimal UAE conditions were extraction temperature of 81°C, extraction time of 1.7h, liquid-solid ratio of 17ml/g, ultrasonic power of 300W and three extraction cycles. The optimal HWE conditions were 93°C extraction temperature, 3.6h extraction time, 21ml/g liquid-solid ratio and three extraction cycles. UAE offered a higher extraction yield with a shorter time, lower temperature and a lower solvent consumption compared with HWE, and the extracted polysaccharides possessed a higher antioxidant capacity. Therefore, UAE could be used as an alternative to conventional HWE for SGRP extraction. PMID:27032488

  12. Novel imaging technologies for characterization of microbial extracellular polysaccharides

    Directory of Open Access Journals (Sweden)

    Magnus Borstad Lilledahl

    2015-05-01

    Full Text Available Understanding of biology is underpinned by the ability to observe structures at various length scales. This is so in a historical context and is also valid today. Evolution of novel insight often emerges from technological advancement. Recent developments in imaging technologies that is relevant for characterization of extracullar microbiological polysaccharides are summarized. Emphasis is on scanning probe and optical based techniques since these tools offers imaging capabilities under aqueous conditions more closely resembling the physiological state than other ultramicroscopy imaging techniques. Following the demonstration of the scanning probe microscopy principle, novel operation modes to increase data capture speed towards video rate, exploitation of several cantilever frequencies, and advancement of utilization of specimen mechanical properties as contrast, also including their mode of operation in liquid, have been developed on this platform. Combined with steps in advancing light microscopy with resolution beyond the far field diffraction limit, non-linear methods and combinations of the various imaging modalities, the potential ultramicroscopy toolbox available for characterization of exopolysaccharides are richer than ever. Examples of application of such ultramicroscopy strategies range from imaging of isolated microbial polysaccharides, structures being observed when they are involved in polyelectrolyte complexes, aspects of their enzymatic degradation and cell surface localization of secreted polysaccharides. These, and other examples, illustrate that the advancement in imaging technologies relevant for exopolysaccharides characterization supports characterization of structural aspects.

  13. Polysaccharides with immunomodulating properties from the bark of Parkia biglobosa.

    Science.gov (United States)

    Zou, Yuan-Feng; Zhang, Bing-Zhao; Inngjerdingen, Kari Tvete; Barsett, Hilde; Diallo, Drissa; Michaelsen, Terje Einar; El-Zoubair, Elnour; Paulsen, Berit Smestad

    2014-01-30

    The bark of Parkia biglobosa is used in traditional medicine to cure a wide range of illnesses. Polysaccharides were extracted from the bark with 50% ethanol-water, 50°C and 100°C water, and seven active fractions obtained by anion exchange chromatography and gel filtration. The complement fixation and macrophage stimulating activities of the different fractions were determined. The acidic fractions PBEII-I and PBEII-IV were the most active in the complement fixation assay, but the other fractions were also potent compared to the positive control BPII from Biophytum petersianum. Fractions PBEII-I and PBEII-IV were also the most potent fractions in stimulating macrophages to release nitric oxide. Structural studies showed that PBEII-I and PBEII-IV were pectic type polysaccharides, containing arabinogalactan type II structures. The observed differences in biological activities among the seven purified polysaccharide sub-fractions are probably due to differences in monosaccharide compositions, linkage types and molecular sizes.

  14. Immunomodulatory Activity and Partial Characterisation of Polysaccharides from Momordica charantia

    Directory of Open Access Journals (Sweden)

    Yuan-Yuan Deng

    2014-08-01

    Full Text Available Momordica charantia Linn. is used as an edible and medicinal vegetable in sub-tropical areas. Until now, studies on its composition and related activities have been confined to compounds of low molecular mass, and no data have been reported concerning the plant’s polysaccharides. In this work, a crude polysaccharide of M. charantia (MCP fruit was isolated by hot water extraction and then purified using DEAE-52 cellulose anion-exchange chromatography to produce two main fractions MCP1 and MCP2. The immunomodulatory effects and physicochemical characteristics of these fractions were investigated in vitro and in vivo. The results showed that intragastric administration of 150 or 300 mg·kg−·d−1 of MCP significantly increased the carbolic particle clearance index, serum haemolysin production, spleen index, thymus index and NK cell cytotoxicity to normal control levels in cyclophosphamide (Cy-induced immunosuppressed mice. Both MCP1 and MCP2 effectively stimulated normal and concanavalin A-induced splenic lymphocyte proliferation in vitro at various doses. The average molecular weights of MCP1 and MCP2, which were measured using high-performance gel permeation chromatography, were 8.55 × 104 Da and 4.41 × 105 Da, respectively. Both fractions exhibited characteristic polysaccharide bands in their Fourier transform infrared spectrum. MCP1 is mainly composed of glucose and galactose, and MCP2 is mainly composed of glucose, mannose and galactose. The results indicate that MCP and its fractions have good potential as immunotherapeutic adjuvants.

  15. Preparation and Identification of Angelica sinensis Polysaccharide-iron Complex

    Institute of Scientific and Technical Information of China (English)

    WANG Kai-ping; ZHANG Yu; DAI Li-quan

    2005-01-01

    Angelica sinensis polysaccharide(ASP) was extracted from Angelica sinensis by boiling water. An Angelica sinensis polysaccharide-iron complex(APC) was prepared under the alkaline condition by adding a ferric chloride solution to the ASP solution. Then some identifiable properties of the complex were studied. The content of iron (Ⅲ) in the complex was determined with iodometry. The thermal property, the microscopic structure, the spectral characteristics, and N, C, H contents of the complex were examined by a variety of techniques including DSC, TEM, IR,NMR, and elemental analysis. The content of iron (Ⅲ) in the complex ranges from 10% to 40%. The DSC result shows that the melting point of the complex is about 450 ℃. The TEM result shows that the complex has an iron(Ⅲ)core(β-FeOOH core) linked by hydroxy and oxy bridges, with the polysaccharide chains attached to the surface of the core. The IR and NMR results also show that there is aβ-FeOOH core in the complex. The elemental analysis shows that the contents of N, C , H in the complex are, respectively, lower than those of N, C, H in ASP. All our studies indicate that the APC consists of aβ-FeOOH core surrounded by ASP.

  16. Extraction and purification of the polysaccharides in Hippohaere rhamnoides L.

    Institute of Scientific and Technical Information of China (English)

    XU Yaqin; JIN Ting; YU Zeyuan; FU Hong

    2007-01-01

    The different extraction technology and purification technology of Hippohpae rhamoides polysaccharides were researched in the paper. The best method of papain extraction were obtained, the ratio of papain 2%, pH at 5.5, temperature at 45℃ and extraction time of 20 min were suitable for papain extraction. The highest content of Hippohpae rhamoides polysaccharides was 44.28 mg·g-1. The optimum process of ultrasonic extraction were obtained, namely extracted for 55 min at 480 W with the material ratio of 1:20. The highest content of Hippohpae rhamoides polysaccharides was 48.63 mg·g-1. The results showed that the ultrasonic and papain extraction together was the best method, the content was 54.30 mg·g-1. After the removing protein, pigment and dialysis. Two fraction were separated from the purified Hippohpae rhamoides by DEAE-cellulose chromatography, the main fraction was collected finally. The fraction was identified by Sepharose CL-4B gel filtration. Ultraviolet spectrometry, freeze-thawing analysis showed that fraction was purified. Its molecular weight was probably 109.4 ku.

  17. Bacterial cellulose biosynthesis: diversity of operons, subunits, products and functions

    Science.gov (United States)

    Römling, Ute; Galperin, Michael Y.

    2015-01-01

    Summary Recent studies of bacterial cellulose biosynthesis, including structural characterization of a functional cellulose synthase complex, provided the first mechanistic insight into this fascinating process. In most studied bacteria, just two subunits, BcsA and BcsB, are necessary and sufficient for the formation of the polysaccharide chain in vitro. Other subunits – which differ among various taxa – affect the enzymatic activity and product yield in vivo by modulating expression of biosynthesis apparatus, export of the nascent β-D-glucan polymer to the cell surface, and the organization of cellulose fibers into a higher-order structure. These auxiliary subunits play key roles in determining the quantity and structure of the resulting biofilm, which is particularly important for interactions of bacteria with higher organisms that lead to rhizosphere colonization and modulate virulence of cellulose-producing bacterial pathogens inside and outside of host cells. Here we review the organization of four principal types of cellulose synthase operons found in various bacterial genomes, identify additional bcs genes that encode likely components of the cellulose biosynthesis and secretion machinery, and propose a unified nomenclature for these genes and subunits. We also discuss the role of cellulose as a key component of biofilms formed by a variety of free-living and pathogenic bacteria and, for the latter, in the choice between acute infection and persistence in the host. PMID:26077867

  18. Pneumococcal Conjugate Vaccines Overcome Splenic Dependency of Antibody Response to Pneumococcal Polysaccharides

    OpenAIRE

    Breukels, Mijke A.; Zandvoort, Andre; van den Dobbelsteen, Germie P. J. M.; van den Muijsenberg, Adrie; Lodewijk, Monique E.; Beurret, Michel; Pieter A Klok; Timens, Wim; Rijkers, Ger T.

    2001-01-01

    Protection against infections with Streptococcus pneumoniae depends on the presence of antibodies against capsular polysaccharides that facilitate phagocytosis. Asplenic patients are at increased risk for pneumococcal infections, since both phagocytosis and the initiation of the antibody response to polysaccharides take place in the spleen. Therefore, vaccination with pneumococcal polysaccharide vaccines is recommended prior to splenectomy, which, as in the case of trauma, is not always feasi...

  19. Immunochemical and Biological Characterization of Three Capsular Polysaccharides from a Single Bacteroides fragilis Strain

    OpenAIRE

    Wiltrud M Kalka-Moll; Wang, Ying(School of Physics, Shandong University, Jinan, 250100, PR China); Comstock, L. E.; Gonzalez, Sylvia E.; Tzianabos, Arthur O.; Dennis L Kasper

    2001-01-01

    Although Bacteroides fragilis accounts for only 0.5% of the normal human colonic flora, it is the anaerobic species most frequently isolated from intra-abdominal and other infections with an intestinal source. The capsular polysaccharides of B. fragilis are part of a complex of surface polysaccharides and are the organism's most important virulence factors in the formation of intra-abdominal abscesses. Two capsular polysaccharides from strain NCTC 9343, PS A1 and PS B1, have been characterize...

  20. PolysacDB: A Database of Microbial Polysaccharide Antigens and Their Antibodies

    OpenAIRE

    Abhijit Aithal; Arun Sharma; Shilpy Joshi; Raghava, Gajendra P S; Varshney, Grish C.

    2012-01-01

    Vaccines based on microbial cell surface polysaccharides have long been considered as attractive means to control infectious diseases. To realize this goal, detailed systematic information about the antigenic polysaccharide is necessary. However, only a few databases that provide limited knowledge in this area are available. This paper describes PolysacDB, a manually curated database of antigenic polysaccharides. We collected and compiled comprehensive information from literature and web reso...

  1. Structural characteristics of polysaccharides that induce protection against intra-abdominal abscess formation.

    OpenAIRE

    Tzianabos, A O; Onderdonk, A B; Zaleznik, D F; Smith, R. S.; Kasper, D L

    1994-01-01

    Bacteroides fragilis is the anaerobe most commonly isolated from clinical cases of intra-abdominal sepsis. In a rodent model of this disease process, intraperitoneal injection of the capsular polysaccharide complex (CPC) from B. fragilis provokes abscess formation, while subcutaneous administration of this complex confers protection against B. fragilis-induced intra-abdominal abscesses. The CPC consists of two discrete polysaccharides, polysaccharides A and B (PS A and PS B), each possessing ...

  2. Effects of sweet cassava polysaccharide extracts on endurance exercise in rats

    OpenAIRE

    Yen, Chia Hung; Tsao, Te Hung; Huang, Cheng Uan; Yang, Chang Bin; Kuo, Chung Sheng

    2013-01-01

    Background Sweet cassava tubers have abundant carbohydrates consisting of monosaccharides and polysaccharides. In addition, polysaccharides extracted from plants improve sports performance, according to recent studies. We therefore examined whether the administration of sweet cassava polysaccharides (SCPs) benefited endurance performance in rats Methods Male Sprague–Dawley rats (n = 30, 7 weeks old) were divided into three groups: control (C), exercise (Ex), and exercise plus SCPs administrat...

  3. [Determination of constituents of polysaccharide and contents of saccharide from Mongolian medicine Agari-8].

    Science.gov (United States)

    Zhao, Yu-Ying; Song, Juan-Juan; Zhao, Yu-Qin; Xu, Xiu-Ting; Hai, Ping

    2007-04-01

    The water soluble polysaccharide was extracted from Agari-8, and the contents of the water soluble polysaccharide were determined by phenyl hydrate-sulfuric acid method. The average recovery was 101.80%. The RSD was 0. 92Y. The components of the water soluble polysaccharide were identified by gas chromatography with: arabinose, xylose, mannose and glucose in the molar ratio of 0.40 : 0.10 : 5.67 : 22.78. Their IR and UV spectra were studied. PMID:17608211

  4. Diagnosis of bacterial vaginosis

    Directory of Open Access Journals (Sweden)

    Đukić Slobodanka

    2013-01-01

    Full Text Available Bacterial vaginosis is a common, complex clinical syndrome characterized by alterations in the normal vaginal flora. When symptomatic, it is associated with a malodorous vaginal discharge and on occasion vaginal burning or itching. Under normal conditions, lactobacilli constitute 95% of the bacteria in the vagina. Bacterial vaginosis is associated with severe reduction or absence of the normal H2O2­producing lactobacilli and overgrowth of anaerobic bacteria and Gardnerella vaginalis, Atopobium vaginae, Mycoplasma hominis and Mobiluncus species. Most types of infectious disease are diagnosed by culture, by isolating an antigen or RNA/DNA from the microbe, or by serodiagnosis to determine the presence of antibodies to the microbe. Therefore, demonstration of the presence of an infectious agent is often a necessary criterion for the diagnosis of the disease. This is not the case for bacterial vaginosis, since the ultimate cause of the disease is not yet known. There are a variety of methods for the diagnosis of bacterial vaginosis but no method can at present be regarded as the best. Diagnosing bacterial vaginosis has long been based on the clinical criteria of Amsel, whereby three of four defined criteria must be satisfied. Nugent’s scoring system has been further developed and includes validation of the categories of observable bacteria structures. Up­to­date molecular tests are introduced, and better understanding of vaginal microbiome, a clear definition for bacterial vaginosis, and short­term and long­term fluctuations in vaginal microflora will help to better define molecular tests within the broader clinical context.

  5. Ability of chitosan gels to disrupt bacterial biofilms and their applications in the treatment of bacterial vaginosis.

    Science.gov (United States)

    Kandimalla, Karunya K; Borden, Emma; Omtri, Rajesh S; Boyapati, Siva Prasad; Smith, Michael; Lebby, Kimberly; Mulpuru, Maanavi; Gadde, Mounika

    2013-07-01

    Recurrence of bacterial vaginosis is attributed to the inability of various formulations to disrupt bacterial biofilms. A negatively charged polysaccharide matrix coats the bacterial communities in the biofilm and restricts the penetration of antibiotics. Therefore, bacteria in the deeper segments of the biofilm persist and perpetuate the infection. In this study, we have tested the efficacy of two bioadhesive polymers, cationic chitosan and anionic polycarbophil, to disrupt Pseudomonas aeruginosa biofilms grown in the Center for Disease Control bioreactor as well as on the 96-well plates. The biofilms were treated with various concentrations of polycarbophil and chitosan at pH 4 or 6. Biofilm integrity following various treatments was evaluated by crystal violet stain and laser confocal microscopy employing Syto9 (live-cell stain) and propidium iodide (dead-cell stain). These studies demonstrated that chitosan gel disrupts the P. aeruginosa biofilm more effectively than does polycarbophil; and this effect is independent of the pH and charge densities on either polymers.

  6. Metabolic engineering of microbes for oligosaccharide and polysaccharide synthesis

    Directory of Open Access Journals (Sweden)

    Chen Rachel

    2006-07-01

    Full Text Available Abstract Metabolic engineering has recently been embraced as an effective tool for developing whole-cell biocatalysts for oligosaccharide and polysaccharide synthesis. Microbial catalysts now provide a practical means to derive many valuable oligosaccharides, previously inaccessible through other methods, in sufficient quantities to support research and clinical applications. The synthesis process based upon these microbes is scalable as it avoids expensive starting materials. Most impressive is the high product concentrations (up to 188 g/L achieved through microbe-catalyzed synthesis. The overall cost for selected molecules has been brought to a reasonable range (estimated $ 30–50/g. Microbial synthesis of oligosaccharides and polysaccharides is a carbon-intensive and energy-intensive process, presenting some unique challenges in metabolic engineering. Unlike nicotinamide cofactors, the required sugar nucleotides are products of multiple interacting pathways, adding significant complexity to the metabolic engineering effort. Besides the challenge of providing the necessary mammalian-originated glycosyltransferases in active form, an adequate uptake of sugar acceptors can be an issue when another sugar is necessary as a carbon and energy source. These challenges are analyzed, and various strategies used to overcome these difficulties are reviewed in this article. Despite the impressive success of the microbial coupling strategy, there is a need to develop a single strain that can achieve at least the same efficiency. Host selection and the manner with which the synthesis interacts with the central metabolism are two important factors in the design of microbial catalysts. Additionally, unlike in vitro enzymatic synthesis, product degradation and byproduct formation are challenges of whole-cell systems that require additional engineering. A systematic approach that accounts for various and often conflicting requirements of the synthesis holds

  7. Bacterial glycosyltransferase toxins.

    Science.gov (United States)

    Jank, Thomas; Belyi, Yury; Aktories, Klaus

    2015-12-01

    Mono-glycosylation of host proteins is a common mechanism by which bacterial protein toxins manipulate cellular functions of eukaryotic target host cells. Prototypic for this group of glycosyltransferase toxins are Clostridium difficile toxins A and B, which modify guanine nucleotide-binding proteins of the Rho family. However, toxin-induced glycosylation is not restricted to the Clostridia. Various types of bacterial pathogens including Escherichia coli, Yersinia, Photorhabdus and Legionella species produce glycosyltransferase toxins. Recent studies discovered novel unexpected variations in host protein targets and amino acid acceptors of toxin-catalysed glycosylation. These findings open new perspectives in toxin as well as in carbohydrate research.

  8. Salt Effect on the Antioxidant Activity of Red Microalgal Sulfated Polysaccharides in Soy-Bean Formula.

    Science.gov (United States)

    Burg, Ariela; Oshrat, Levy-Ontman

    2015-10-01

    Sulfated polysaccharides produced by microalgae, which are known to exhibit various biological activities, may potentially serve as natural antioxidant sources. To date, only a few studies have examined the antioxidant bioactivity of red microalgal polysaccharides. In this research, the effect of different salts on the antioxidant activities of two red microalgal sulfated polysaccharides derived from Porphyridium sp. and Porphyridium aerugineum were studied in a soy bean-based infant milk formula. Salt composition and concentration were both shown to affect the polysaccharides' antioxidant activity. It can be postulated that the salt ions intefer with the polysaccharide chains' interactions and alter their structure, leading to a new three-dimensional structure that better exposes antiooxidant sites in comparison to the polysaccharide without salt supplement. Among the cations that were studied, Ca(2+) had the strongest enhancement effect on antioxidant activities of both polysaccharides. Understanding the effect of salts on polysaccharides' stucture, in addition to furthering knowledge on polysaccharide bioactivities, may also shed light on the position of the antioxidant active sites. PMID:26492255

  9. Polysaccharides serve as scaffold of biofilms formed by mucoid Pseudomonas aeruginosa

    DEFF Research Database (Denmark)

    Yang, Liang; Hengzhuang, Wang; Wu, Hong;

    2012-01-01

    from biofilms formed by mucoid P. aeruginosa were investigated. Alginate is not an essential structure component for mucoid P. aeruginosa biofilms. Genetic studies revealed that Pel and Psl polysaccharides serve as essential scaffold and mediate macrocolony formation in mucoid P. aeruginosa biofilms....... The Psl polysaccharide is more important than Pel polysaccharide in mucoid P. aeruginosa biofilm structure maintenance and phagocytosis resistance. The polysaccharides were further found to protect mucoid P. aeruginosa strain from host immune clearance in a mouse model of acute lung infection....

  10. Seizures Complicating Bacterial Meningitis

    Directory of Open Access Journals (Sweden)

    J Gordon Millichap

    2004-09-01

    Full Text Available The clinical data of 116 patients, 1 month to <5 years of age, admitted for bacterial meningitis, and grouped according to those with and without seizures during hospitalization, were compared in a study at Buddhist Dalin Tzu Chi General Hospital, Chang Gung Memorial Hospital and other centers in Taiwan.

  11. Bacterial extracellular lignin peroxidase

    Science.gov (United States)

    Crawford, Donald L.; Ramachandra, Muralidhara

    1993-01-01

    A newly discovered lignin peroxidase enzyme is provided. The enzyme is obtained from a bacterial source and is capable of degrading the lignin portion of lignocellulose in the presence of hydrogen peroxide. The enzyme is extracellular, oxidative, inducible by lignin, larch wood xylan, or related substrates and capable of attacking certain lignin substructure chemical bonds that are not degradable by fungal lignin peroxidases.

  12. Bacterial Skin Infections

    Science.gov (United States)

    ... or scraped, the injury should be washed with soap and water and covered with a sterile bandage. Petrolatum may be applied to open areas to keep the tissue moist and to try to prevent bacterial invasion. Doctors recommend that people do not use ...

  13. Vimentin in Bacterial Infections

    DEFF Research Database (Denmark)

    Mak, Tim N; Brüggemann, Holger

    2016-01-01

    filaments (IFs). IFs have not only roles in maintaining the structural integrity of the cell, but they are also involved in many cellular processes including cell adhesion, immune signaling, and autophagy, processes that are important in the context of bacterial infections. Here, we summarize the knowledge...

  14. Bacterial microflora of nectarines

    Science.gov (United States)

    Microflora of fruit surfaces has been the best source of antagonists against fungi causing postharvest decays of fruit. However, there is little information on microflora colonizing surfaces of fruits other than grapes, apples, and citrus fruit. We characterized bacterial microflora on nectarine f...

  15. Modeling intraocular bacterial infections.

    Science.gov (United States)

    Astley, Roger A; Coburn, Phillip S; Parkunan, Salai Madhumathi; Callegan, Michelle C

    2016-09-01

    Bacterial endophthalmitis is an infection and inflammation of the posterior segment of the eye which can result in significant loss of visual acuity. Even with prompt antibiotic, anti-inflammatory and surgical intervention, vision and even the eye itself may be lost. For the past century, experimental animal models have been used to examine various aspects of the pathogenesis and pathophysiology of bacterial endophthalmitis, to further the development of anti-inflammatory treatment strategies, and to evaluate the pharmacokinetics and efficacies of antibiotics. Experimental models allow independent control of many parameters of infection and facilitate systematic examination of infection outcomes. While no single animal model perfectly reproduces the human pathology of bacterial endophthalmitis, investigators have successfully used these models to understand the infectious process and the host response, and have provided new information regarding therapeutic options for the treatment of bacterial endophthalmitis. This review highlights experimental animal models of endophthalmitis and correlates this information with the clinical setting. The goal is to identify knowledge gaps that may be addressed in future experimental and clinical studies focused on improvements in the therapeutic preservation of vision during and after this disease. PMID:27154427

  16. Polysaccharides purified from wild Cordyceps activate FGF2/FGFR1c signaling

    Science.gov (United States)

    Zeng, Yangyang; Han, Zhangrun; Yu, Guangli; Hao, Jiejie; Zhang, Lijuan

    2015-02-01

    Land animals as well as all organisms in ocean synthesize sulfated polysaccharides. Fungi split from animals about 1.5 billion years ago. As fungi make the evolutionary journey from ocean to land, the biggest changes in their living environment may be a sharp decrease in salt concentration. It is established that sulfated polysaccharides interact with hundreds of signaling molecules and facilitate many signaling transduction pathways, including fibroblast growth factor (FGF) and FGF receptor signaling pathway. The disappearance of sulfated polysaccharides in fungi and plants on land might indicate that polysaccharides without sulfation might be sufficient in facilitating protein ligand/receptor interactions in low salinity land. Recently, it was reported that plants on land start to synthesize sulfated polysaccharides in high salt environment, suggesting that fungi might be able to do the same when exposed in such environment. Interestingly, Cordyceps, a fungus habituating inside caterpillar body, is the most valued traditional Chinese Medicine. One of the important pharmaceutical active ingredients in Cordyceps is polysaccharides. Therefore, we hypothesize that the salty environment inside caterpillar body might allow the fungi to synthesize sulfated polysaccharides. To test the hypothesis, we isolated polysaccharides from both lava and sporophore of wild Cordyceps and also from Cordyceps militaris cultured without or with added salts. We then measured the polysaccharide activity using a FGF2/FGFR1c signaling-dependent BaF3 cell proliferation assay and found that polysaccharides isolated from wild Cordyceps activated FGF2/FGFR signaling, indicating that the polysaccharides synthesized by wild Cordyceps are indeed different from those by the cultured mycelium.

  17. Polysaccharides Purified from Wild Cordyceps Activate FGF2/FGFR1c Signaling

    Institute of Scientific and Technical Information of China (English)

    ZENG Yangyang; HAN Zhangrun; YU Guangli; HAO Jiejie; ZHANG Lijuan

    2015-01-01

    Land animals as well as all organisms in ocean synthesize sulfated polysaccharides. Fungi split from animals about 1.5 billion years ago. As fungi make the evolutionary journey from ocean to land, the biggest changes in their living environment may be a sharp decrease in salt concentration. It is established that sulfated polysaccharides interact with hundreds of signaling molecules and facilitate many signaling transduction pathways, including fibroblast growth factor (FGF) and FGF receptor signaling pathway. The disappearance of sulfated polysaccharides in fungi and plants on land might indicate that polysaccharides without sulfation might be sufficient in facilitating protein ligand/receptor interactions in low salinity land. Recently, it was reported that plants on land start to synthesize sulfated polysaccharides in high salt environment, suggesting that fungi might be able to do the same when ex-posed in such environment. Interestingly, Cordyceps, a fungus habituating inside caterpillar body, is the most valued traditional Chi-nese Medicine. One of the important pharmaceutical active ingredients in Cordyceps is polysaccharides. Therefore, we hypothesize that the salty environment inside caterpillar body might allow the fungi to synthesize sulfated polysaccharides. To test the hypothesis, we isolated polysaccharides from both lava and sporophore of wild Cordyceps and also fromCordyceps militaris cultured without or with added salts. We then measured the polysaccharide activity using a FGF2/FGFR1c signaling-dependent BaF3 cell proliferation assay and found that polysaccharides isolated from wild Cordyceps activated FGF2/FGFR signaling, indicating that the polysaccha-rides synthesized by wild Cordyceps are indeed different from those by the cultured mycelium.

  18. Structure of Plant Cell Walls : XVIII. An Analysis of the Extracellular Polysaccharides of Suspension-Cultured Sycamore Cells.

    Science.gov (United States)

    Stevenson, T T; McNeil, M; Darvill, A G; Albersheim, P

    1986-04-01

    The water-soluble polysaccharides (SEPS) secreted into the medium by suspension-cultured sycamore cells were examined to determine whether the polysaccharides were the same as those present in the walls of sycamore cells. The SEPS were made more amenable to fractionation by treatment with a highly purified alpha-1,4-endopolygalacturonase (EPG). The EPG-treated SEPS were fractionated by anion-exchange and gelpermeation chromatography. The following polysaccharides were found: xyloglucan, arabinoxylan, at least two arabinogalactans, a rhamnogalacturonan-II-like polysaccharide, and a polygalacturonic acid-rich polysaccharide. The oligogalacturonide fragments expected from EPG-digested homogalacturonan were also identified. Evidence was obtained for the presence of a rhamnogalacturonan-I-like polysaccharide. All of the above polysaccharides have been isolated from or are believed to be present in sycamore cell walls. Furthermore, all of the noncellulosic polysaccharides known to be present in sycamore cell-walls appear to be present in the SEPS.

  19. Utilization of Glycosyltransferases for the Synthesis of a Densely Packed Hyperbranched Polysaccharide Brush Coating as Artificial Glycocalyx

    NARCIS (Netherlands)

    van der Vlist, Jeroen; Schonen, Iris; Loos, Katja; Schönen, Iris

    2011-01-01

    Densely packed polysaccharide brushes consisting of alpha-D-glucose residues were grafted from modified silicon substrates. Potato phosphorylase was herein used to grow linear polysaccharide chains from silicon tethered maltoheptaose oligosaccharides using glucose-1-phosphate as donor substrate. The

  20. Heme uptake in bacterial pathogens

    OpenAIRE

    Contreras, Heidi; Chim, Nicholas; Credali, Alfredo; Goulding, Celia W.

    2014-01-01

    Iron is an essential nutrient for the survival of organisms. Bacterial pathogens possess specialized pathways to acquire heme from their human hosts. In this review, we present recent structural and biochemical data that provide mechanistic insights into several bacterial heme uptake pathways, encompassing the sequestration of heme from human hemoproteins to secreted or membrane-associated bacterial proteins, the transport of heme across bacterial membranes, and the degradation of heme within...

  1. Extraction and Antibacterial Activity of Polysaccharides from Schisandra chinensis (Turcz.) Baill Leaves%北五味子叶多糖的提取及抑菌活性

    Institute of Scientific and Technical Information of China (English)

    许瑞波; 高颖颖; 万蓓蓓; 王新新; 周杰兴

    2012-01-01

    采用水提醇沉法,通过单因素和正交试验研究北五味子叶多糖(polysaccharides from Schisandra chinensis(Turcz.)Baill leaves,PSL)的提取工艺,并考察PSL对大肠杆菌、金黄色葡萄球菌和枯草芽孢杆菌的抑制作用。结果表明:PSL最适宜提取工艺条件为料液比1:45(g/mL)、提取温度90℃、提取时间1h、提取2次。在此条件下,PSL的提取率为9.08%。用Sevag法对PSL进行初步提纯,用UV光谱检测脱蛋白效果,发现该法不能有效去除其所含的蛋白质,而且经Sevag法处理后的PSL色泽变黑。同时,利用红外光谱法对PSL进行表征,证明其具备一般多糖类物质及肽键的光谱特征,说明该多糖可能是以共价键与含肽键的蛋白质或多肽结合的糖复合物。抑菌实验结果表明,PSL对3种细菌具有一定的抑制活性。%The extraction of polysaccharides from Schisandra chinensis(Turcz.) Baill leaves(PSL) was optimized using onefactor-at-a-time and orthogonal array design method.Meanwhile,the inhibitory activities of PSL against Staphylococcus aureus,Escherichia coli and Bacillus subtilis were investigated.The results showed that the optimal conditions for PSL extraction were determined as two extraction cycles with distilled water at a solid/solvent ratio of 1:45(g/mL) at 90 ℃ for 1 h.Under these conditions,the extraction yield of PSL was 9.08%.The PSL obtained could not be effectively deproteinized by Sevag method according to UV spectroscopic analysis and its color was darkened.Meanwhile,IR spectroscopic analysis demonstrated that this PSL possessed common spectral characteristics of polysaccharides and peptide bonds,suggesting that it might be formed by conjugation of polysaccharides with proteins or polypeptides through peptide bonds.Furthermore,the polysaccharide extract possessed inhibitory activities against three bacterial strains under investigation.

  2. Polysaccharide-based aerogel microspheres for oral drug delivery.

    Science.gov (United States)

    García-González, C A; Jin, M; Gerth, J; Alvarez-Lorenzo, C; Smirnova, I

    2015-03-01

    Polysaccharide-based aerogels in the form of microspheres were investigated as carriers of poorly water soluble drugs for oral administration. These bio-based carriers may combine the biocompatibility of polysaccharides and the enhanced drug loading capacity of dry aerogels. Aerogel microspheres from starch, pectin and alginate were loaded with ketoprofen (anti-inflammatory drug) and benzoic acid (used in the management of urea cycle disorders) via supercritical CO2-assisted adsorption. Amount of drug loaded depended on the aerogel matrix structure and composition and reached values up to 1.0×10(-3) and 1.7×10(-3) g/m(2) for ketoprofen and benzoic acid in starch microspheres. After impregnation, drugs were in the amorphous state in the aerogel microspheres. Release behavior was evaluated in different pH media (pH 1.2 and 6.8). Controlled drug release from pectin and alginate aerogel microspheres fitted Gallagher-Corrigan release model (R(2)>0.99 in both cases), with different relative contribution of erosion and diffusion mechanisms depending on the matrix composition. Release from starch aerogel microspheres was driven by dissolution, fitting the first-order kinetics due to the rigid starch aerogel structure, and showed different release rate constant (k1) depending on the drug (0.075 and 0.160 min(-1) for ketoprofen and benzoic acid, respectively). Overall, the results point out the possibilities of tuning drug loading and release by carefully choosing the polysaccharide used to prepare the aerogels.

  3. Fingerprint profiling of polysaccharide kefiran extracted from kefir grains biomass

    OpenAIRE

    POP, CARMEN; M. Rotar, Ancuta; C. Salanțӑ, Liana; A. Semeniuc, Cristina; Socaciu, Carmen; Sindic, Marianne

    2015-01-01

    Kefiran is a water-soluble polysaccharide extracted from kefir grains biomass. The identification and quantification of kefiran monosaccharides were carried out by HPTLC after the complete acid hydrolysis of kefiran solutions. The mobile phase was a mixture of n-propanol: acetic acid: water (70:20:10, v/v). For derivatization was used p-aminobenzoic acid and o-phosphoric acid in methanol. The identified HPTLC fractions were glucose (Rf 0.71) and galactose (Rf 0.66), which indicates a high pur...

  4. Immunologically active polysaccharides of Arnica montana cell cultures.

    Science.gov (United States)

    Puhlmann, J; Zenk, M H; Wagner, H

    1991-01-01

    From the nutrition medium of Arnica montana cell cultures two homogeneous polysaccharides, an acidic arabino-3,6-galactan-protein with mean Mr of 100,000 and a neutral fucogalactoxyloglucan with mean Mr of 22,500 have been isolated by DEAE-Sepharose CL-6B and Sephacryl S-400 column chromatography. Their structures were elucidated mainly by methylation analysis, partial acidic and enzymatic hydrolysis and 13C NMR spectroscopy. The fucogalactoxyloglucan shows a pronounced enhancement of phagocytosis in vivo. The arabino-3,6-galactan-protein displays a strong anticomplementary effect and stimulates macrophages to excrete the tumour necrosis factor (TNF alpha).

  5. Lycium barbarum Polysaccharides Reduce Exercise-Induced Oxidative Stress

    OpenAIRE

    Tao Ma; Qiongxia Chai; Junlai Zhou; Xiaozhong Shan

    2011-01-01

    The purpose of the present study was to investigate the effects of Lycium barbarum polysaccharides (LBP) on exercise-induced oxidative stress in rats. Rats were divided into four groups, i.e., one control group and three LBP treated groups. The animals received an oral administration of physiological saline or LBP (100, 200 and 400 mg/kg body weight) for 28 days. On the day of the exercise test, rats were required to run to exhaustion on the treadmill. Body weight, endurance time, malondialde...

  6. Chemical Characteristic of Bioactive Polysaccharides Isolated from Ornithogalum caudatum Ait.

    Institute of Scientific and Technical Information of China (English)

    SHI Lei; LI Juan; LIU Wen-Xiang; WANG Yong; LIU Zhi-qiang; LIU Shu-ying

    2003-01-01

    A water-soluble crude extract prepared from Ornithogalum caudatum Ait.(OCA) showing a high immunomodulating activitiy was isolated and characterized by virtue of gel filtration and column chromatography. The presence of the monosaccharides has been established by the chemical analysis. The quantitative analysis of the alditol acetate derivatives of them showed the ratios of the monosaccharides analyzed by means of GC respectively. The concentrations of protein(280 nm) and carbohydrate(496 nm) were detected respectively. The information of the molecular weight from the pure polysaccharide was obtained by several standard Dextrans from the Sephadex chromatography.

  7. Extracellular polysaccharide production in Bacillus licheniformis SVD1 and its immunomodulatory effect

    Directory of Open Access Journals (Sweden)

    J. Susan van Dyk

    2012-11-01

    Full Text Available Bacillus licheniformis SVD1 exhibited highest production of three different polysaccharides when sucrose was used as the carbon source for polysaccharide production and yeast extract was used as the nitrogen source. Polysaccharides were characterized using size exclusion chromatography (SEC, thin layer chromatography (TLC, gas chromatography with mass spectrometry (GCMS, and Fourier Transform Infrared (FTIR analysis. Field emission scanning electron microscopy (FESEM and transmission electron microscopy (TEM were used to examine the topography of the cells and polysaccharides. The cell-associated polysaccharides were composed of galactose, while two different polysaccharides were present in the extracellular medium, one of 2,000 kDa (EPS1, consisting of fructose monomers and identified as a levan with (2→6-linkages and (1→2-branching linkages. The other extracellular polysaccharide (EPS2 consisted of mannose and galactose and had a range of sizes as identified through SEC. All three polysaccharides displayed an immune modulatory effect as measured using Interleukin 6 (IL6 and tumor necrosis factor alpha (TNFα.

  8. A nuclear magnetic resonance approach to the comparison of mucoadhesive properties of polysaccharides for ophthalmic uses.

    Science.gov (United States)

    Uccello-Barretta, Gloria; Nazzi, Samuele; Balzano, Federica; Sansò, Marco

    2011-03-15

    Mucoadhesive properties of tamarind seed polysaccharide (TSP) and larch arabinogalactan (AG), which are developed for ophthalmic applications, were investigated by NMR spectroscopy. Polysaccharide to mucin affinities were compared by using ketotifen fumarate as low molecular weight interaction probe. Proton selective relaxation rate measurements revealed enhanced affinity of TSP to mucin with respect to AG.

  9. Characterisation of antioxidant and antiproliferative acidic polysaccharides from Chinese wolfberry fruits

    NARCIS (Netherlands)

    He, N.W.; Yang, X.B.; Jiao, Y.D.; Tian, L.; Zhao, Y.

    2012-01-01

    Wolfberry fruit polysaccharides (WFPs) were isolated by hot-water extraction and ethanol precipitation. With HPLC analysis, WFPs were for the first time identified as acidic polysaccharides with galacturonic acid being the main component monosaccharide (24.9%), followed by galactose (21.3%), arabino

  10. Synthesis, characterization and evaluation of thiolated tamarind seed polysaccharide as a mucoadhesive polymer.

    Science.gov (United States)

    Kaur, Harmanmeet; Yadav, Shikha; Ahuja, Munish; Dilbaghi, Neeraj

    2012-11-01

    In the present study, thiol-functionalization of tamarind seed polysaccharide was carried out by esterification with thioglycolic acid. Thiol-functionalization was confirmed by SH stretch in Fourier-transformed infra-red spectra at 2586 cm(-1). It was found to possess 104.5 mM of thiol groups per gram. The results of differential scanning calorimetry and X-ray diffraction study indicate increase in crystallinity. Polymer compacts of thiolated tamarind seed polysaccharide required 6.85-fold greater force to detach from the mucin coated membrane than that of tamarind seed polysaccharide. Comparative evaluation of Carbopol-based metronidazole gels containing thiolated tamarind seed polysaccharide with gels containing tamarind seed polysaccharide for mucoadhesive strength using chicken ileum by modified balance method revealed higher mucoadhesion of gels containing thiolated tamarind seed polysaccharide. Further, the gels containing tamarind seed polysaccharide and thiolated tamarind seed polysaccharide released the drug by Fickian-diffusion following the first-order and Higuchi's-square root release kinetics, respectively.

  11. Optimization of ultrasonic circulating extraction of polysaccharides from Asparagus officinalis using response surface methodology.

    Science.gov (United States)

    Zhao, Qingsheng; Kennedy, John F; Wang, Xiaodong; Yuan, Xiaofan; Zhao, Bing; Peng, Youshun; Huang, Yunxiang

    2011-08-01

    Polysaccharides were extracted from Asparagus officinalis. A novel ultrasonic circulating extraction (UCE) technology was applied for the polysaccharide extraction. Three-factor-three-level Box-Behnken design was employed to optimize ultrasonic power, extraction time and the liquid-solid ratio to obtain a high polysaccharide yield. The optimal extraction conditions were as follows: ultrasonic power was 600 W, extraction time was 46 min, the liquid-solid ratio was 35 mL/g. Under these conditions, the experimental yield of polysaccharides was 3.134%, which was agreed closely to the predicted value. The average molecular weight of A. officinalis polysaccharide was about 6.18×10(4) Da. The polysaccharides were composed of glucose, fucose, arabinose, galactose and rhamnose in a ratio of 2.18:1.86:1.50:0.98:1.53. Compared with hot water extraction (HWE), UCE showed time-saving, higher yield and no influence on the structure of asparagus polysaccharides. The results indicated that ultrasonic circulating extraction technology could be an effective and advisable technique for the large scale production of plant polysaccharides. PMID:21549748

  12. Physical Properties Giving the Sensory Perception of Whey Proteins/Polysaccharide Gels

    NARCIS (Netherlands)

    Berg, van den L.; Vliet, van T.; Linden, van der E.; Boekel, van M.A.J.S.; Velde, van de F.

    2008-01-01

    Establishing relationships between physical and sensorial properties of semi-solid foods is essential to develop tailored products. Whey protein/polysaccharide mixed gels were used to model both natural and fabricated semi-solid foods. The presence of various polysaccharides modulated the microstruc

  13. Isolation and structure elucidation of pectic polysaccharide from rose hip fruits (Rosa canina L.)

    NARCIS (Netherlands)

    Ognyanov, Manol; Remoroza, Connie; Schols, Henk A.; Georgiev, Yordan; Kratchanova, Maria; Kratchanov, Christo

    2016-01-01

    A pectic polysaccharide from rose hip (RH) fruits has been obtained by extraction with 1% aqueous citric acid. It was found that the polysaccharide fraction mainly consisted of galacturonic acid (45.5%) next to galactose (5.5%) and arabinose (4.7%). RH pectin is having a relatively high degree of

  14. Polysaccharide enhances Radix Saposhnikoviae efficacy through inhibiting chromones decomposition in intestinal tract

    Science.gov (United States)

    Yang, Jing-Ming; Jiang, Hua; Dai, Hong-Liang; Wang, Zi-Wei; Jia, Gui-Zhi; Meng, Xiang-Cai

    2016-01-01

    Vegetative but not reproductive stage of Saposhnikovia divaricate (Turxz.) schischk possesses pharmacological activities. However, our recent study showed that reproductive S. divaricate supplemented with polysaccharide showed evidently elevated pharmacological activities and increased cimifugin content in rat serum. The aims of present study were to assess the influence of polysaccharides on the chromones pharmacological activities in Radix Saposhnikoviae (RS), the dried root of vegetative stage of S. divaricate, and to explore the underlying mechanisms. Only cimifugin was detected in the plasma of chromone treated animals and RS polysaccharide significantly increased the plasma content of cimifugin. It was shown that neither cimifugin absorption nor glycoside components transformation in simulated digestive fluid was affected by RS polysaccharide. However, a significant promotion of transformation of cimifugin to more stable prime-O-glucosylcimifugin (PGCN) by RS polysaccharide, and a protective effect of polysaccharide on chromone components were observed in small intestine solutions. Meanwhile, RS polysaccharide produced a significant elevation of cimifugin and PGCN concentration in vivo. Based on these findings, we concluded that RS polysaccharide could greatly increase the content of cimifugin, which might be related to its degradation-proof effect on cimifugin, via transforming cimifugin to comparatively more stable PGCN and spatial structure protection. PMID:27595868

  15. Structural studies of the methylated, acidic polysaccharide associated with coccoliths of Emiliania huxleyi (Lohmann) Kamptner

    NARCIS (Netherlands)

    Vliegenthart, J.F.G.; Fichtinger-Schepman, A.M.J.; Kamerling, J.P.; Versluis, C.

    1981-01-01

    For the structure analysis of the methylated, acidic polysaccharide associated with the coccoliths of the alga Emiliania huxleyi (Lohmann) Kamptner, the native, the carboxyl-reduced, and the desulphated, carboxyl-reduced polysaccharides have been submitted to methylation analysis. Graded hydrolysis

  16. Targeted and non-targeted effects in cell wall polysaccharides from transgenetically modified potato tubers

    NARCIS (Netherlands)

    Huang, J.H.

    2016-01-01

    The plant cell wall is a chemically complex network composed mainly of polysaccharides. Cell wall polysaccharides surround and protect plant cells and are responsible for the stability and rigidity of plant tissue. Pectin is a major component of primary cell wall and the middle lamella of plants. Ho

  17. Bacterial chemoreceptors and chemoeffectors.

    Science.gov (United States)

    Bi, Shuangyu; Lai, Luhua

    2015-02-01

    Bacteria use chemotaxis signaling pathways to sense environmental changes. Escherichia coli chemotaxis system represents an ideal model that illustrates fundamental principles of biological signaling processes. Chemoreceptors are crucial signaling proteins that mediate taxis toward a wide range of chemoeffectors. Recently, in deep study of the biochemical and structural features of chemoreceptors, the organization of higher-order clusters in native cells, and the signal transduction mechanisms related to the on-off signal output provides us with general insights to understand how chemotaxis performs high sensitivity, precise adaptation, signal amplification, and wide dynamic range. Along with the increasing knowledge, bacterial chemoreceptors can be engineered to sense novel chemoeffectors, which has extensive applications in therapeutics and industry. Here we mainly review recent advances in the E. coli chemotaxis system involving structure and organization of chemoreceptors, discovery, design, and characterization of chemoeffectors, and signal recognition and transduction mechanisms. Possible strategies for changing the specificity of bacterial chemoreceptors to sense novel chemoeffectors are also discussed.

  18. Bacterial Colony Optimization

    Directory of Open Access Journals (Sweden)

    Ben Niu

    2012-01-01

    Full Text Available This paper investigates the behaviors at different developmental stages in Escherichia coli (E. coli lifecycle and developing a new biologically inspired optimization algorithm named bacterial colony optimization (BCO. BCO is based on a lifecycle model that simulates some typical behaviors of E. coli bacteria during their whole lifecycle, including chemotaxis, communication, elimination, reproduction, and migration. A newly created chemotaxis strategy combined with communication mechanism is developed to simplify the bacterial optimization, which is spread over the whole optimization process. However, the other behaviors such as elimination, reproduction, and migration are implemented only when the given conditions are satisfied. Two types of interactive communication schemas: individuals exchange schema and group exchange schema are designed to improve the optimization efficiency. In the simulation studies, a set of 12 benchmark functions belonging to three classes (unimodal, multimodal, and rotated problems are performed, and the performances of the proposed algorithms are compared with five recent evolutionary algorithms to demonstrate the superiority of BCO.

  19. [Bacterial diseases of rape].

    Science.gov (United States)

    Zakharova, O M; Mel'nychuk, M D; Dankevych, L A; Patyka, V P

    2012-01-01

    Bacterial destruction of the culture was described and its agents identified in the spring and winter rape crops. Typical symptoms are the following: browning of stem tissue and its mucilagization, chlorosis of leaves, yellowing and beginning of soft rot in the place of leaf stalks affixion to stems, loss of pigmentation (violet). Pathogenic properties of the collection strains and morphological, cultural, physiological, and biochemical properties of the agents of rape's bacterial diseases isolated by the authors have been investigated. It was found that all the isolates selected by the authors are highly or moderately aggressive towards different varieties of rape. According to the complex of phenotypic properties 44% of the total number of isolates selected by the authors are related to representatives of the genus Pseudomonas, 37% - to Xanthomonas and 19% - to Pectobacterium. PMID:23293826

  20. Bacterial transformation of terpenoids

    International Nuclear Information System (INIS)

    Data on the bacterial transformation of terpenoids published in the literature in the past decade are analyzed. Possible pathways for chemo-, regio- and stereoselective modifications of terpenoids are discussed. Considerable attention is given to new technological approaches to the synthesis of terpenoid derivatives suitable for the use in the perfume and food industry and promising as drugs and chiral intermediates for fine organic synthesis. The bibliography includes 246 references

  1. Supramolecular bacterial systems

    OpenAIRE

    Sankaran, Shrikrishnan

    2015-01-01

    For nearly over a decade, a wide variety of dynamic and responsive supramolecular architectures have been investigated and developed to address biological systems. Since the non-covalent interactions between individual molecular components in such architectures are similar to the interactions found in living systems, it was possible to integrate chemically-synthesized and naturally-occurring components to create platforms with interesting bioactive properties. Bacterial cells and recombinant ...

  2. Bacterial Colony Optimization

    OpenAIRE

    Ben Niu; Hong Wang

    2012-01-01

    This paper investigates the behaviors at different developmental stages in Escherichia coli (E. coli) lifecycle and developing a new biologically inspired optimization algorithm named bacterial colony optimization (BCO). BCO is based on a lifecycle model that simulates some typical behaviors of E. coli bacteria during their whole lifecycle, including chemotaxis, communication, elimination, reproduction, and migration. A newly created chemotaxis strategy combined with communication mechanism i...

  3. Antigenic polysaccharides of bacteria. 14. Structure of the O-specific polysaccharide chain of the lipopolysaccharide of pseudomonas aeruginosa O12 (Lanyi)

    International Nuclear Information System (INIS)

    The mild-alkaline hydrolysis of the lipopolysaccharide of Pseudomonas aeruginosa O12 (Lanyi classification) has given the O-specific polysaccharide, which is constructed of D-ribose and N-acetyl-D-galactosamine residues. The disaccharide structure for the repeating unit of this polysaccharide has been established by a nondestructive method as the result of the complete deciphering of its 1H and 13C NMR spectra using homonuclear and selective heteronuclear 13C {1H} double resonance

  4. Extraction of Angelica sinensis polysaccharides using ultrasound-assisted way and its bioactivity.

    Science.gov (United States)

    Zhao, Ying; Shi, Yongyong; Yang, Huixin; Mao, Lijuan

    2016-07-01

    In the present article, ultrasound-assisted extraction (UAE) of polysaccharides from Angelica sinensis were investigated. The aim of the study is to examine the extraction parameters such as ultrasound power (140-180W), the ratio of liquid to solid (5-7), extraction time (40-50min) and extraction temperature (80-100°C) and to obtain the best possible combinations of these parameters through response surface methodology (RSM). Based on contour plots and variance analysis, optimum operational conditions for maximizing polysaccharides yield were found to be 180w, 7, 45min and 90°C. Under the optimum operating conditions determined, 6.96% polysaccharides were achieved. In addition, the results showed that A. sinensis polysaccharides (ASP) could increase antioxidant enzymes activities and decrease the MDA levels in the skeletal muscle of exhaustive exercise rats. This study provides strong evidence that A. sinensis polysaccharides supplementation possessed protective effects against exhaustive exercise-induced oxidative stress.

  5. Screening of polysaccharides from tamarind, fenugreek and jackfruit seeds as pharmaceutical excipients.

    Science.gov (United States)

    Nayak, Amit Kumar; Pal, Dilipkumar; Santra, Kousik

    2015-08-01

    The paper describes the isolation and screening of plant polysaccharides namely tamarind seed polysaccharide (TSP), fenugreek seed mucilage (FSM) and jackfruit seed starch (JFSS) from tamarind (Tamarindus indica L.) seeds, fenugreek (Trigonella foenum-graecum L.) seeds and jackfruit (Artocarpus heterophyllus L.) seeds, respectively. The yields of isolated dried TSP, FSM and JFSS were 47.00%, 17.36% and 18.86%, respectively. Various physicochemical properties like colour, odour, taste, solubility in water, pH and viscosity of these isolated plant polysaccharides were assessed. Isolated polysaccharide samples were subjected to some phytochemical identification tests. FTIR and (1)H NMR analyses of isolated polysaccharides were performed, which suggest the presence of sugar residues. Isolated TSP, FSM and JFSS can be used as pharmaceutical excipients in various pharmaceutical formulations.

  6. Preparation of animal polysaccharides nanofibers by electrospinning and their potential biomedical applications.

    Science.gov (United States)

    Zhao, Wen; Liu, Wenlong; Li, Jiaojiao; Lin, Xiao; Wang, Ying

    2015-02-01

    Animal polysaccharides belong to a class of biological macromolecules. They are natural biopolymers with numerous advantages for biomedical applications, such as biocompatibility, biodegradability, non-antigenicity and non-toxicity. Electrospinning is a versatile and facile technique which can produce continuous fibers with nanoscale from a wide range of natural and synthetic polymers. The review aims to provide an up-to-date overview of the preparation of animal polysaccharides nanofibers by electrospinning and their potential biomedical applications such as tissue engineering, wound healing, and drug delivery. Various animal polysaccharides including chitin and chitosan (CS), hyaluronic acid (HA), heparin and heparan sulfate (HS), and chondroitin sulfate (ChS), are discussed. The challenges and some useful strategies in electrospinning of animal polysaccharides also are summarized. In addition, future study of animal polysaccharides nanofibers by electrospinning is proposed. PMID:24733749

  7. Physical modifications of polysaccharide from Inonotus obliquus and the antioxidant properties.

    Science.gov (United States)

    Zhang, Ning; Chen, Haixia; Ma, Lishuai; Zhang, Yu

    2013-03-01

    Physical modification of polysaccharides exerted better biological properties because of the change of physicochemical properties. Polysaccharides from Inonotus obliquus (IOPS) were modified by acid, alkali hydrolysis, thermal and ultrasonic treatment in this study. The physicochemical and antioxidant properties of IOPS and its physical modified products were comparatively investigated by chemical methods, gas chromatography, size exclusion chromatography, scanning electron micrograph, circular dichroism spectra, and ferric reducing power assay and lipid peroxidation inhibition assay, respectively. Results showed that physicochemical and antioxidant properties of IOPS were changed after the physical modification of acid, alkali hydrolysis, thermal and ultrasonic treatment. Thermal treated polysaccharide (Th-IOPS) and ultrasonic treated polysaccharide (Ul-IOPS) showed the properties of lower molecular weight distribution, lower intrinsic viscosity, a hyperbranched conformation, and higher antioxidant abilities on ferric-reducing power and lipid peroxidation inhibition activity compared with the native polysaccharide IOPS. Th-IOPS and Ul-IOPS might be explored as a novel potential antioxidant for food industry. PMID:23270834

  8. Chemical modification and antioxidant activities of polysaccharide from mushroom Inonotus obliquus.

    Science.gov (United States)

    Ma, Lishuai; Chen, Haixia; Zhang, Yu; Zhang, Ning; Fu, Lingling

    2012-06-20

    Chemical modification polysaccharides exerted potent biological property which was related to the physicochemical properties. In the present study, polysaccharides from Inonotus obliquus were modified by suflation, acetylation and carboxymethylation. The physicochemical and antioxidant properties of I. obliquus polysaccharide (IOPS) and its derivatives were comparatively investigated by chemical methods, gas chromatography, size exclusion chromatography, scanning electron micrograph, infrared spectra and circular dichroism spectra, and ferric reducing power assay and lipid peroxidation inhibition assay, respectively. Results showed that physicochemical and antioxidant properties of IOPS were differed each other after the chemical modification of suflation, acetylation and carboxymethylation. Among the three derivatives, acetylationed polysaccharide (Ac-IOPS) resulted in lower molecular weight distribution, lower intrinsic viscosity, a hyperbranched conformation, higher antioxidant abilities on ferric-reducing power and lipid peroxidation inhibition activity compared with the native polysaccharide IOPS. Ac-IOPS might be explored as a novel potential antioxidant for human consumption. PMID:24750732

  9. Lycium barbarum polysaccharides promotes in vivo proliferation of adult rat retinal progenitor cells

    Directory of Open Access Journals (Sweden)

    Hua Wang

    2015-01-01

    Full Text Available Lycium barbarum is a widely used Chinese herbal medicine prescription for protection of optic nerve. However, it remains unclear regarding the effects of Lycium barbarum polysaccharides, the main component of Lycium barbarum, on in vivo proliferation of adult ciliary body cells. In this study, adult rats were intragastrically administered low- and high-dose Lycium barbarum polysaccharides (1 and 10 mg/kg for 35 days and those intragastrically administered phosphate buffered saline served as controls. The number of Ki-67-positive cells in rat ciliary body in the Lycium barbarum polysaccharides groups, in particular low-dose Lycium barbarum polysaccharides group, was significantly greater than that in the phosphate buffered saline group. Ki-67-positive rat ciliary body cells expressed nestin but they did not express glial fibrillary acidic protein. These findings suggest that Lycium barbarum polysaccharides can promote the proliferation of adult rat retinal progenitor cells and the proliferated cells present with neuronal phenotype.

  10. In Vitro Antioxidant Activities of Sulfated Derivatives of Polysaccharides Extracted from Auricularia auricular

    Science.gov (United States)

    Zhang, Hua; Wang, Zhen-Yu; Yang, Lin; Yang, Xin; Wang, Xue; Zhang, Zhi

    2011-01-01

    In this research, two types of sulfated polysaccharide derivatives were successfully synthesized. Their antioxidant activities were investigated by employing various established in vitro systems. In addition, the degree of sulfation was evaluated using ion-chromatography and IR spectra. The results verify that, when employing scavenging superoxide radical tests, both the sulfation of acid Auricularia auricular polysaccharides (SAAAP) and the sulfation of neutral Auricularia auricular polysaccharides (SNAAP) derivatives possessed considerable antioxidant activity and had a more powerful antioxidant competence than that of the native non-sulfated polysaccharides (AAAP and NAAP). On the other hand, AAAP and NAAP exhibited stronger activity on scavenging both the hydroxyl radical and lipid peroxidation. Available data obtained with in vitro measurements indicates that the sulfated groups of AAAP and NAAP played an important role on antioxidant activity. In sum, the research demonstrates that the antioxidant activity of sulfated polysaccharide derivatives in vitro has a potential significance for seeking new natural antioxidant protective agents. PMID:21686185

  11. Structural determination of the polysaccharide isolated from biofilms produced by a clinical strain of Klebsiella pneumoniae.

    Science.gov (United States)

    Cescutti, Paola; De Benedetto, Gianluigi; Rizzo, Roberto

    2016-07-22

    Klebsiella pneumoniae are Gram negative opportunistic pathogens producing capsular (K) polysaccharides. Seventy-seven different K antigens have been described and they are the basis for K serotyping. Capsular polysaccharides are important virulence factors and have a relevant role for the structure of biofilm communities. Nevertheless, little information is available on the polysaccharides produced in biofilm matrices by Klebsiella spp. In the present study, a clinical isolate of Klebsiella pneumoniae was grown both on cellulose membranes deposited on agar plates, where it formed an adherent biofilm, and in liquid medium, where it formed floating biofilms (flocs). Extraction and purification of the polysaccharide fraction showed that only one main carbohydrate polymer was present in both adherent biofilms and flocs. Composition and linkage analysis, Smith degradation followed by ESI-MS, 1D and 2D NMR spectroscopy revealed that the polysaccharide belong to the type K24 and has the following structure. PMID:27182661

  12. A unique variant of streptococcal group O-antigen (C-polysaccharide) that lacks phosphocholine

    DEFF Research Database (Denmark)

    Bergström, N; Jansson, P.-E.; Kilian, Mogens;

    2003-01-01

    previously characterized forms of C-polysaccharide, which all contain one or two choline residues per repeat. The following structure of the repeating unit of the SK598 polysaccharide was established: where AAT is 2-acetamido-4-amino-2,4,6-trideoxy-d-galactose. This structure is identical to the double......Streptococcus mitis strain SK598, which represents a subgroup of biovar 1, possesses a unique variant of the C-polysaccharide found in the cell wall of all strains of Streptococcus pneumoniae and in some strains of S. mitis. This new variant lacks the choline methyl groups in contrast to the...... choline-substituted form of C-polysaccharide, except that it is substituted with ethanolamine instead of choline. This extends the number of recognized C-polysaccharide variants to four....

  13. Antiviral Potential of Algae Polysaccharides Isolated from Marine Sources: A Review

    Directory of Open Access Journals (Sweden)

    Azin Ahmadi

    2015-01-01

    Full Text Available From food to fertilizer, algal derived products are largely employed in assorted industries, including agricultural, biomedical, food, and pharmaceutical industries. Among different chemical compositions isolated from algae, polysaccharides are the most well-established compounds, which were subjected to a variety of studies due to extensive bioactivities. Over the past few decades, the promising results for antiviral potential of algae-derived polysaccharides have advocated them as inordinate candidates for pharmaceutical research. Numerous studies have isolated various algal polysaccharides possessing antiviral activities, including carrageenan, alginate, fucan, laminaran, and naviculan. In addition, different mechanisms of action have been reported for these polysaccharides, such as inhibiting the binding or internalization of virus into the host cells or suppressing DNA replication and protein synthesis. This review strives for compiling previous antiviral studies of algae-derived polysaccharides and their mechanism of action towards their development as natural antiviral agents for future investigations.

  14. Studies on the Antiviral Activities in vitro of Polysaccharide from Eucheuma striatum

    Institute of Scientific and Technical Information of China (English)

    CEN,Ying-Zhou; KHOO,Gaik-Ming; YE,Shao-Ming; RUI,Wen

    2004-01-01

    @@ To assay the antiviral activities on HSV-1 and CVB3 in vitro of the polysaccharide from Eucheuma striatum, its antiviral mechanism was explored. Vero cells were infected by HSV-1 and CVB3, and they were cultured with serial dilutions of polysaccharide. The cells cytotoxicity of Polysaccharide was evaluated by the MTT method. The inhibitory effects were evaluated by the cytopathic effect (CPE). Its antiviral mechanism was researched by the method of giving samples in different time. The polysaccharide could inhibit the CPE of cells infected by HSV-1 and CVB3. It showed low cytotoxicity on vero cells. Its antiviral activities were better than those of acyclovir and ribavirin which were run in parallel as the positive control samples. The polysaccharide from Eucheuma striatum has potent antiviral activities. Its antiviral mechanism is that it can prevent the virus from absorbing to the cell surface.

  15. BcsA and BcsB form the catalytically active core of bacterial cellulose synthase sufficient for in vitro cellulose synthesis

    OpenAIRE

    Omadjela, Okako; Narahari, Adishesh; Strumillo, Joanna; Mélida, Hugo; Mazur, Olga; Bulone, Vincent; Zimmer, Jochen

    2013-01-01

    Cellulose is the most abundant biopolymer on Earth, primarily formed by vascular plants, but also by some bacteria. Bacterial extracellular polysaccharides, such as cellulose and alginate, are an important component of biofilms, which are multicellular, usually sessile, aggregates of bacteria. Biofilms exhibit a greater resistance to antimicrobial treatments compared with isolated bacteria and thus are a particular concern to human health. Cellulose synthases synthesize cellulose by polymeriz...

  16. Micropatterned polysaccharide surfaces via laser ablation for cell guidance

    Energy Technology Data Exchange (ETDEWEB)

    Barbucci, Rolando; Lamponi, Stefania; Pasqui, Daniela; Rossi, Antonella; Weber, Elisabetta

    2003-03-03

    Micropatterned materials were obtained by a controlled laser ablation of a photoimmobilised homogeneous layer of hyaluronic acid (Hyal) and its sulphated derivative (HyalS). The photoimmobilisation was performed by coating the polysaccharide, adequately functionalised with a photoreactive group, on aminosilanised glass substrate and immobilising it on the surface under UV light. Hyal or HyalS photoimmobilised samples were then subjected to laser ablation with wavelengths in the UV regions in order to drill the pattern. Four different patterns with stripes of 100, 50, 25 and 10 {mu}m were generated. A chemical characterisation by attenuated total reflection/Fourier transform infrared (ATR/FT-IR) and time of flight-secondary ions mass spectrometry (TOF-SIMS) confirmed the success of the laser ablation procedure and the presence of alternating stripes of polysaccharide and native glass. The exact dimensions of the stripes were determined by atomic force microscopy. The analysis of cell behaviour in terms of adhesion, proliferation and movement using mouse fibroblasts (3T3 line) and bovine aortic endothelial cells (BAEC) was also performed.

  17. Motility in cyanobacteria: polysaccharide tracks and Type IV pilus motors.

    Science.gov (United States)

    Wilde, Annegret; Mullineaux, Conrad W

    2015-12-01

    Motility in cyanobacteria is useful for purposes that range from seeking out favourable light environments to establishing symbioses with plants and fungi. No known cyanobacterium is equipped with flagella, but a diverse range of species is able to 'glide' or 'twitch' across surfaces. Cyanobacteria with this capacity range from unicellular species to complex filamentous forms, including species such as Nostoc punctiforme, which can generate specialised motile filaments called hormogonia. Recent work on the model unicellular cyanobacterium Synechocystis sp. PCC 6803 has shown that its means of propulsion has much in common with the twitching motility of heterotrophs such as Pseudomonas and Myxococcus. Movement depends on Type IV pili, which are extended, adhere to the substrate and then retract to pull the cell across the surface. Previous work on filamentous cyanobacteria suggested a very different mechanism, with movement powered by the directional extrusion of polysaccharide from pores close to the cell junctions. Now a new report by Khayatan and colleagues in this issue of Molecular Microbiology suggests that the motility of Nostoc hormogonia has much more in common with Synechocystis than was previously thought. In both cases, polysaccharide secretion is important for preparing the surface, but the directional motive force comes from Type IV pili.

  18. Polysaccharides from Arctium lappa L.: Chemical structure and biological activity.

    Science.gov (United States)

    Carlotto, Juliane; de Souza, Lauro M; Baggio, Cristiane H; Werner, Maria Fernanda de P; Maria-Ferreira, Daniele; Sassaki, Guilherme L; Iacomini, Marcello; Cipriani, Thales R

    2016-10-01

    The plant Arctium lappa L. is popularly used to relieve symptoms of inflammatory disorders. A crude polysaccharide fraction (SAA) resulting of aqueous extraction of A. lappa leaves showed a dose dependent anti-edematogenic activity on carrageenan-induced paw edema, which persisted for up to 48h. Sequential fractionation by ultrafiltration at 50kDa and 30kDa cut-off membranes yielded three fractions, namely RF50, RF30, and EF30. All these maintained the anti-edematogenic effect, but RF30 showed a more potent action, inhibiting 57% of the paw edema at a dose of 4.9mg/kg. The polysaccharide RF30 contained galacturonic acid, galactose, arabinose, rhamnose, glucose, and mannose in a 7:4:2:1:2:1 ratio and had a Mw of 91,000g/mol. Methylation analysis and NMR spectroscopy indicated that RF30 is mainly constituted by a type I rhamnogalacturonan branched by side chains of types I and II arabinogalactans, and arabinan.

  19. A Novel Tissue Adhesive Composed of Modified Gelatin and Polysaccharides

    Institute of Scientific and Technical Information of China (English)

    Xiumei MO; Hiroo IWATA; Yoshito IKADA

    2000-01-01

    A two-component adhesive glue was prepared from gelatin and polysaccharides. Gelatin was modified with ethylenediamine (ED) in the presence of water soluble carbodiimine (WSC) to introduce more amino groups into the original gelatin, while dextran and hydroxyethyl-starch (HES) were oxidized by sodium periodate to convert neighbouring hydroxyl groups into dialdehyde groups. Upon mixing the two polymer components in aqueous solution, Schiff's base reaction occurred between the amino groups in the modified gelatin and the aldehyde groups in the modified polysaccharides to give intermolecular crosslinking and gel formation. This new glue showed a capability to stop bleeding and seal tissues when a cut liver of rat was used for hemostatic experiments. It could also form a gel much faster than fibrin glue in in-vitro experiments. The fastest gel formation took place within 2 sec and the bonding strength to porcine skin was about 225gf/cm2 when an amino-gelatin (55% amino) and an aldehyde-HES (>84% dialdehyde) was mixed. In contrast, the gelation time and bonding strength of fibrin gluewere 5 seconds and 120gf/cm2, respectively. The effective adhesive properties have also been identified by the animal experiments of rat.

  20. Representative parameter of immunostimulatory ginseng polysaccharide to predict radioprotection

    Energy Technology Data Exchange (ETDEWEB)

    Son, Hyeog Jin; Shim, Ji Young; Ahn, Ji Yeon; Yun, Yeon Sook; Song, Jie Young [Korea Institute of Radiological and Medical Sciences, Seoul (Korea, Republic of)

    2008-09-15

    According to the increase in the use of radiotherapy to cancer patients, many approaches have been tried to develop new agents for the protection of surrounding normal tissues. However, it is still few applied in the clinic as a radioprotector. We aim to find a representative parameter for radioprotection to easily predict the activity of in vivo experiment from the results of in vitro screening. The polysaccharide extracted from Panax ginseng was used in this study because the immunostimulator has been regarded as one of the radioprotective agent category and was already reported having a promising radioprotective activity through the increase of hematopoietic cells and the production of several cytokines. Mitogenic activity, AK cells activity and nitric oxide production were monitored for the in vitro immunological assay, and endogenous Colony-Forming Unit (e-CFU) was measured as in vivo radioprotective parameter. The immunological activity was increased by the galactose contents of ginseng polysaccharide dependently. The result of this study suggests that mitogenic activity of splenocytes demonstrated a good correlation with in vivo radioprotective effect, and may be used as a representative parameter to screen the candidates for radioprotector.

  1. Isolation, characterization and antioxidant activity of polysaccharide from Schisandra sphenanthera.

    Science.gov (United States)

    Zhao, Ting; Mao, Guanghua; Feng, Weiwei; Mao, Riwen; Gu, Xiaoyun; Li, Ting; Li, Qian; Bao, Yongtuan; Yang, Liuqing; Wu, Xiangyang

    2014-05-25

    A water-soluble polysaccharide (SSPP11) from Schisandra sphenanthera was purified by DEAE-cellulose and Sephadex G-100 columns. Structure of SSPP11 and its antioxidant activity was evaluated. Results showed that SSPP11 has a molecular weight of 5.3×10(3)Da and is composed of Man, Glu and Gal. A linkage analysis and NMR study revealed that SSPP11 has a backbone of →1)-d-Man-(6→, →1)-d-Manp-(2→, →1)-d-Glup(4→, →1)-d-Glup-(6→, →1)-d-Galp-(4→, →1)-d-Galp-(4,6→ and →1)-d-Manp-(3,6→, with Man, Glu and Gal, which are distributed in branched chains. The Congo red absorption test revealed that SSPP11 has a triple helix stereo-configuration. Moreover, antioxidant activity of SSPP11 was stronger than the polysaccharide from Schisandra chinensis (Turcz.) Baill. In sum, this study demonstrates that a moderate molecular weight, triple helix stereo-configuration and higher degree of branching are beneficial for exerting antioxidant activity.

  2. A novel chemistry for conjugating pneumococcal polysaccharides to Luminex microspheres.

    Science.gov (United States)

    Schlottmann, Sonela A; Jain, Neil; Chirmule, Narendra; Esser, Mark T

    2006-02-20

    Here we describe a novel method to conjugate pneumococcal polysaccharides (PnPS) to Luminex microspheres for use in serological assays. 4-(4,6-dimethoxy[1,3,5]triazin-2-yl)-4-methyl-morpholinium (DMTMM) modification of PnPS and conjugation to carboxyl functional groups on Luminex microspheres (COOH-DMTMM method) was shown to be a reproducible chemistry that efficiently conjugated PnPS to Luminex microspheres without affecting the antigenicity of a broad set of PnPS. The COOH-DMTMM method was compared to three other methods for robustness, reproducibility and effect on PnPS antigenicity in a multiplexed assay format. The other methods examined included adsorption of the unmodified PnPS to Luminex microspheres, oxidation of the PnPS to conjugate them to amino-modified microspheres using carbodiimide chemistry and poly-l-lysine modification of the PnPS before conjugating to carboxy Luminex microspheres using carbodiimide chemistry. Of the four methods, the COOH-DMTMM chemistry was shown to be a robust methodology, producing stable PnPS coupled microspheres with a 4-log dynamic range and low cross-reactivity when used in a PnPS-specific IgG serology assay. This novel chemistry should be useful for developing serological assays to measure antibodies to polysaccharides for use in vaccine and epidemiology studies. PMID:16448665

  3. Structure of polysaccharide antibiotics; Structure des antibiotiques polysaccharidiques

    Energy Technology Data Exchange (ETDEWEB)

    Matutano, L. [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

    1966-07-01

    Study of the structure of antibiotics having two or several sugars in their molecule. One may distinguish: the polysaccharide antibiotics themselves, made up of two or several sugars either with or without nitrogen, such as streptomycin, neomycins, paromomycine, kanamycin, chalcomycin; the hetero-polysaccharide antibiotics made up of one saccharide part linked to an aglycone of various type through a glucoside: macrolide, pigment, pyrimidine purine. Amongst these latter are: erythromycin, magnamycin, spiramycin, oleandomycin, cinerubin and amicetin. The sugars can either play a direct role in biochemical reactions or act as a dissolving agent, as far as the anti-microbe power of these antibiotics is concerned. (author) [French] Etude de la structure des antibiotiques qui possedent dans leur molecule deux ou plusieurs sucres. On distingue: les antibiotiques polysaccharidiques proprement dits, constitues de deux eu plusieurs sucres azotes ou non, tels que streptomycines, neomycines, paromomycines, kanamycine, chalcomycine; les antibiotiques heteropolysaccharidiques formes d'une partie saccharidique liee glycosidiquement a un aglycone de nature diverse: macrolide - pigment - purine pyrimidine. On compte parmi ceux-ci: erythroraycine rnagnamycine, spiromycine, oleandomycine, cinerubine et amicetine. Dans le pouvoir antimicrobien de ces antibiotiques les sucres peuvent jouer soit un role direct dans les reactions biochimiques, soit agir comme solubilisant. (auteur)

  4. Scleroglucan: A Versatile Polysaccharide for Modified Drug Delivery

    Directory of Open Access Journals (Sweden)

    Franco Alhaique

    2005-01-01

    Full Text Available Scleroglucan is a natural polysaccharide, produced by fungi of the genus Sclerotium, that has been extensively studied for various commercial applications (secondary oil recovery, ceramic glazes, food, paints, etc. and also shows several interesting pharmacological properties. This review focuses its attention on the use of scleroglucan, and some derivatives, in the field of pharmaceutics and in particular for the formulation of modified-release dosage forms. The reported investigations refer mainly to the following topics: natural scleroglucan suitable for the preparation of sustained release tablets and ocular formulations; oxidized and crosslinked scleroglucan used as a matrix for dosage forms sensitive to environmental conditions; co-crosslinked scleroglucan/gellan whose delivery rate can be affected by calcium ions. Furthermore, a novel hydrogel obtained with this polysaccharide and borate ions is described, and the particular structure of this hydrogel network has been interpreted in terms of conformational analysis and molecular dynamics. Profound attention is devoted to the mechanisms involved in drug release from the tested dosage forms that depend, according to the specific preparation, on swelling and/or diffusion. Experimental data are also discussed on the basis of a mathematical approach that allows a better understanding of the behavior of the tested polymeric materials.

  5. Polysaccharides from Arctium lappa L.: Chemical structure and biological activity.

    Science.gov (United States)

    Carlotto, Juliane; de Souza, Lauro M; Baggio, Cristiane H; Werner, Maria Fernanda de P; Maria-Ferreira, Daniele; Sassaki, Guilherme L; Iacomini, Marcello; Cipriani, Thales R

    2016-10-01

    The plant Arctium lappa L. is popularly used to relieve symptoms of inflammatory disorders. A crude polysaccharide fraction (SAA) resulting of aqueous extraction of A. lappa leaves showed a dose dependent anti-edematogenic activity on carrageenan-induced paw edema, which persisted for up to 48h. Sequential fractionation by ultrafiltration at 50kDa and 30kDa cut-off membranes yielded three fractions, namely RF50, RF30, and EF30. All these maintained the anti-edematogenic effect, but RF30 showed a more potent action, inhibiting 57% of the paw edema at a dose of 4.9mg/kg. The polysaccharide RF30 contained galacturonic acid, galactose, arabinose, rhamnose, glucose, and mannose in a 7:4:2:1:2:1 ratio and had a Mw of 91,000g/mol. Methylation analysis and NMR spectroscopy indicated that RF30 is mainly constituted by a type I rhamnogalacturonan branched by side chains of types I and II arabinogalactans, and arabinan. PMID:27311502

  6. Microbially produced extracellular poly-saccharidic Pu(IV)- binding ligands

    International Nuclear Information System (INIS)

    Full text of publication follows: The investigation of the Pu-binding properties of ligands for diverse extracellular polysaccharides (EPS) is of relevance for the quantitative understanding of colloidal barriers to radionuclide migration. The EPS isolated for this study were from four different bacteria species: a) two aerobic soil bacteria: Shewanella putrefaciens CN32 and Pseudomonas fluorescens Biovar II; and b) one anaerobic bacterium, Clostridium sp. BC1. EPS from these bacteria were isolated through repeated ethanol precipitations. The neutral monosaccharides in the EPS from Pseudomonas florescens Biovar II that were determined by GC-MS consisted of rhamnose, fucose, ribose, arabinose, xylose, mannose, galactose and glucose. The potentially Pu(IV) binding EPS ligands were mainly composed of carboxylic acids and other minor poly-anionic groups, e.g., sulphates and phosphates. Up to 70 % of total carbohydrates were hydrophilic uronic acids, and total carbohydrates made up 23-31% of organic carbon for P. florescens Biovar II and 9-17% of organic carbon for S. putrefaciens CN32. Besides the neutral and acidic sugars in the EPS, there were also 2-13 % of more hydrophobic proteins among these bacterial EPS. Pu binding to these exo-polymers showed log Kd values of about 5 - 6, with results strongly dependent on procedural details (e.g., removal of colloids in Pu(IV) tracer and reagent solutions). We hypothesize that the relative hydrophobicity of the EPS ligands affects the outcome in ternary sorption studies with colloidal silica. Experiments with varying relative hydrophobicities of EPS will elucidate the different sorption strengths and/or attachment potentials of the Pu-binding ligands to inorganic surfaces. (authors)

  7. Microbially produced extracellular poly-saccharidic Pu(IV)- binding ligands

    Energy Technology Data Exchange (ETDEWEB)

    Hung, C.C.; Roberts, K.A.; Schwehr, K.A.; Santschi, P.H. [Texas A and M University at Galveston, 5007 Ave U, Galveston, TX 77551 (United States)

    2005-07-01

    Full text of publication follows: The investigation of the Pu-binding properties of ligands for diverse extracellular polysaccharides (EPS) is of relevance for the quantitative understanding of colloidal barriers to radionuclide migration. The EPS isolated for this study were from four different bacteria species: a) two aerobic soil bacteria: Shewanella putrefaciens CN32 and Pseudomonas fluorescens Biovar II; and b) one anaerobic bacterium, Clostridium sp. BC1. EPS from these bacteria were isolated through repeated ethanol precipitations. The neutral monosaccharides in the EPS from Pseudomonas florescens Biovar II that were determined by GC-MS consisted of rhamnose, fucose, ribose, arabinose, xylose, mannose, galactose and glucose. The potentially Pu(IV) binding EPS ligands were mainly composed of carboxylic acids and other minor poly-anionic groups, e.g., sulphates and phosphates. Up to 70 % of total carbohydrates were hydrophilic uronic acids, and total carbohydrates made up 23-31% of organic carbon for P. florescens Biovar II and 9-17% of organic carbon for S. putrefaciens CN32. Besides the neutral and acidic sugars in the EPS, there were also 2-13 % of more hydrophobic proteins among these bacterial EPS. Pu binding to these exo-polymers showed log Kd values of about 5 - 6, with results strongly dependent on procedural details (e.g., removal of colloids in Pu(IV) tracer and reagent solutions). We hypothesize that the relative hydrophobicity of the EPS ligands affects the outcome in ternary sorption studies with colloidal silica. Experiments with varying relative hydrophobicities of EPS will elucidate the different sorption strengths and/or attachment potentials of the Pu-binding ligands to inorganic surfaces. (authors)

  8. Genome-wide identification of Streptococcus pneumoniae genes essential for bacterial replication during experimental meningitis

    DEFF Research Database (Denmark)

    Molzen, T E; Burghout, P; Bootsma, H J;

    2010-01-01

    Meningitis is the most serious of invasive infections caused by the Gram-positive bacterium Streptococcus pneumoniae. Vaccines protect only against a limited number of serotypes, and evolving bacterial resistance to antimicrobials impedes treatment. Further insight into the molecular pathogenesis...... genes mutants of which had become attenuated or enriched, respectively, during infection. The results point to essential roles for capsular polysaccharides, nutrient uptake, and amino acid biosynthesis in bacterial replication during experimental meningitis. The GAF phenotype of a subset of identified...... of invasive pneumococcal disease is required in order to enable the development of new or adjunctive treatments and/or pneumococcal vaccines that are efficient across serotypes. We applied genomic array footprinting (GAF) in the search for S. pneumoniae genes that are essential during experimental meningitis...

  9. Bacterial Glycosyltransferases: Challenges and opportunities of a highly diverse enzyme class toward tailoring natural products

    Directory of Open Access Journals (Sweden)

    Jochen eSchmid

    2016-02-01

    Full Text Available The enzyme subclass of glycosyltransferases (EC 2.4 currently comprises 97 families as specified by CAZy classification. One of their important roles is in the biosynthesis of disaccharides, oligosaccharides and polysaccharides by catalyzing the transfer of sugar moieties from activated donor molecules to other sugar molecules. In addition glycosyltransferases also catalyze the transfer of sugar moieties onto aglycons, which is of great relevance for the synthesis of many high value natural products. Bacterial glycosyltransferases show a higher sequence similarity in comparison to mammalian ones. Even when most glycosyltransferases are poorly explored, state of the art technologies, such as protein engineering, domain swapping or computational analysis strongly enhance our understanding and utilization of these very promising classes of proteins. This perspective article will focus on bacterial glycosyltransferases, especially on classification, screening and engineering strategies to alter substrate specificity. The future development in these fields as well as obstacles and challenges will be highlighted and discussed.

  10. Influence of fermentation conditions on polysaccharide production and the activities of enzymes involved in the polysaccharide synthesis of Cordyceps militaris.

    Science.gov (United States)

    Zhu, Zhen-Yuan; Liu, Xiao-Cui; Dong, Feng-Ying; Guo, Ming-Zhu; Wang, Xiao-Ting; Wang, Zheng; Zhang, Yong-Min

    2016-05-01

    The influence of different fermentation conditions on intracellular polysaccharide (IPS) production and activities of the phosphoglucomutase (PGM), UDPG-pyrophosphorylase (UGP), phosphoglucose isomerase (PGI), UDPG-dehydrogenase (UGD), and glucokinase (GK) implicated in metabolite synthesis in Cordyceps militaris was evaluated. The highest IPS production (327.57 ± 6.27 mg/100 mL) was obtained when the strain was grown in the optimal medium containing glucose (40 g · L(-1)), beef extract (10 g · L(-1)), and CaCO3 (0.5 g · L(-1)), and the initial pH and temperature were 7 and 25 °C, respectively. The activities of PGM, UGP, and PGI were proved to be influenced by the fermentation conditions. A strong correlation between the activities of these enzymes and the production of IPS was found. The transcription level of the pgm gene (encoding PGM) was 1.049 times and 1.467 times compared to the ugp gene and pgi gene (encoding UGP and PGI), respectively, in the optimal culture medium. This result indicated that PGM might be the highly key enzyme to regulate the biosynthesis of IPS of C. militaris in a liquid-submerged culture. Our study might be helpful for further research on the pathway of polysaccharide biosynthesis aimed to improve the IPS production of C. militaris. PMID:26685672

  11. Phase variable expression of capsular polysaccharide modifications allows Campylobacter jejuni to avoid bacteriophage infection in chickens

    Directory of Open Access Journals (Sweden)

    Martine Camilla Holst Sørensen

    2012-02-01

    Full Text Available Bacteriophages are estimated to be the most abundant entities on earth and can be found in every niche where their bacterial hosts reside. The initial interaction between phages and Campylobacter jejuni, a common coloniser of poultry intestines and a major source of foodborne bacterial gastroenteritis in humans, is not well understood. Recently, we isolated and characterised a phage F336 resistant variant of C. jejuni NCTC11168 called 11168R. Comparisons of 11168R with the wildtype lead to the identification of a novel phage receptor, the phase variable O-methyl phosphoramidate (MeOPN moiety of the C. jejuni capsular polysaccharide (CPS. In this study we demonstrate that the 11168R strain has gained cross-resistance to four other phages in our collection (F198, F287, F303 and F326. The reduced plaquing efficiencies suggested that MeOPN is recognized as a receptor by several phages infecting C. jejuni. To further explore the role of CPS modifications in C. jejuni phage recognition and infectivity, we tested the ability of F198, F287, F303, F326 and F336 to infect different CPS variants of NCTC11168, including defined CPS mutants. These strains were characterised by high-resolution magic angle spinning NMR spectroscopy. We found that in addition to MeOPN, the phase variable 3-O-Me and 6-O-Me groups of the NCTC11168 CPS structure may influence the plaquing efficiencies of the phages. Furthermore, co-infection of chickens with both C. jejuni NCTC11168 and phage F336 resulted in selection of resistant C. jejuni bacteria, which either lack MeOPN or gain 6-O-Me groups on their surface, demonstrating that resistance can be acquired in vivo. In summary, we have shown that phase variable CPS structures modulate phage infectivity in C. jejuni and suggest that the constant phage predation in the avian gut selects for changes in these structures leading to a continuing phage-host co-evolution.

  12. Transcriptional responses of Bacillus cereus towards challenges with the polysaccharide chitosan.

    Directory of Open Access Journals (Sweden)

    Hilde Mellegård

    Full Text Available The antibacterial activity of the polysaccharide chitosan towards different bacterial species has been extensively documented. The response mechanisms of bacteria exposed to this biopolymer and the exact molecular mechanism of action, however, have hardly been investigated. This paper reports the transcriptome profiling using DNA microarrays of the type-strain of Bacillus cereus (ATCC 14579 exposed to subinhibitory concentrations of two water-soluble chitosan preparations with defined chemical characteristics (molecular weight and degree of acetylation (F(A. The expression of 104 genes was significantly altered upon chitosan A (weight average molecular weight (M(w 36.0 kDa, F(A = 0.01 exposure and 55 genes when treated with chitosan B (M(w 28.4 kDa, F(A = 0.16. Several of these genes are involved in ion transport, especially potassium influx (BC0753-BC0756. Upregulation of a potassium transporting system coincides with previous studies showing a permeabilizing effect on bacterial cells of this polymer with subsequent loss of potassium. Quantitative PCR confirmed the upregulation of the BC0753 gene encoding the K(+-transporting ATPase subunit A. A markerless gene replacement method was used to construct a mutant strain deficient of genes encoding an ATP-driven K(+ transport system (Kdp and the KdpD sensor protein. Growth of this mutant strain in potassium limiting conditions and under salt stress did not affect the growth pattern or growth yield compared to the wild-type strain. The necessity of the Kdp system for potassium acquisition in B. cereus is therefore questionable. Genes involved in the metabolism of arginine, proline and other cellular constituents, in addition to genes involved in the gluconeogenesis, were also significantly affected. BC2798 encoding a chitin binding protein was significantly downregulated due to chitosan exposure. This study provides insight into the response mechanisms of B. cereus to chitosan treatment and

  13. Transcriptional responses of Bacillus cereus towards challenges with the polysaccharide chitosan.

    Science.gov (United States)

    Mellegård, Hilde; Kovács, Ákos T; Lindbäck, Toril; Christensen, Bjørn E; Kuipers, Oscar P; Granum, Per E

    2011-01-01

    The antibacterial activity of the polysaccharide chitosan towards different bacterial species has been extensively documented. The response mechanisms of bacteria exposed to this biopolymer and the exact molecular mechanism of action, however, have hardly been investigated. This paper reports the transcriptome profiling using DNA microarrays of the type-strain of Bacillus cereus (ATCC 14579) exposed to subinhibitory concentrations of two water-soluble chitosan preparations with defined chemical characteristics (molecular weight and degree of acetylation (F(A))). The expression of 104 genes was significantly altered upon chitosan A (weight average molecular weight (M(w)) 36.0 kDa, F(A) = 0.01) exposure and 55 genes when treated with chitosan B (M(w) 28.4 kDa, F(A) = 0.16). Several of these genes are involved in ion transport, especially potassium influx (BC0753-BC0756). Upregulation of a potassium transporting system coincides with previous studies showing a permeabilizing effect on bacterial cells of this polymer with subsequent loss of potassium. Quantitative PCR confirmed the upregulation of the BC0753 gene encoding the K(+)-transporting ATPase subunit A. A markerless gene replacement method was used to construct a mutant strain deficient of genes encoding an ATP-driven K(+) transport system (Kdp) and the KdpD sensor protein. Growth of this mutant strain in potassium limiting conditions and under salt stress did not affect the growth pattern or growth yield compared to the wild-type strain. The necessity of the Kdp system for potassium acquisition in B. cereus is therefore questionable. Genes involved in the metabolism of arginine, proline and other cellular constituents, in addition to genes involved in the gluconeogenesis, were also significantly affected. BC2798 encoding a chitin binding protein was significantly downregulated due to chitosan exposure. This study provides insight into the response mechanisms of B. cereus to chitosan treatment and the

  14. Application of Alfalfa Polysaccharides in Livestock and Poultry Feeds%苜蓿多糖在畜禽饲料中的应用

    Institute of Scientific and Technical Information of China (English)

    陈元元; 朱宇旌; 张勇

    2013-01-01

    Alfalfa polysaccharides (APS) is a kind of active polysaccharide extracted from leguminous forage alfalfa, and it is very stable containing glucose, mannose, rhamnose and other active ingredients. APS can improve the immune function of livestock and poultry by promoting the growth of animal immune organs and the proliferation and transformation of lymphocytes, and it also has the antioxidant function by eliminating free radicals in animal. Besides, APS has functions of anti-tumor, anti-infections, lowering blood lipids and glucose, anti-bacterial and anti-inflammatory, etc. Much more scholars have been attracted by its abundant resources and toxic-free property. This article summarized the research progresses of APS in livestock and poultry feeds.%苜蓿多糖(alfalfa polysaccharides,APS)是豆科牧草紫花苜蓿中提取的植物活性多糖,性质稳定,含葡萄糖、甘露糖、鼠李糖等活性成分,通过促进畜禽免疫器官的生长和淋巴细胞的增殖转化来提高畜禽的免疫功能,通过清除自由基起到抗氧化作用.另外苜蓿多糖还具有抗肿瘤、抗感染、降血脂、降血糖、抗菌、消炎等多种生物学功能.因其提取来源丰富且无毒害作用而倍受学者们的关注,本文对苜蓿多糖在畜禽饲料中的应用研究进展进行综述.

  15. Comparative evaluation of polysaccharides isolated from Astragalus, oyster mushroom, and yacon as inhibitors of α-glucosidase.

    Science.gov (United States)

    Zhu, Zhen-Yuan; Zhang, Jing-Yi; Chen, Li-Jing; Liu, Xiao-Cui; Liu, Yang; Wang, Wan-Xiao; Zhang, Yong-Min

    2014-04-01

    The incidence of diabetes has increased considerably, and become the third serious chronic disease following cancer and cardiovascular diseases. Though acarbose, metformin, and 1-deoxynojirimycin have good efficacy for clinical application as hypoglycemic drugs, their expensive costs and some degree of side effects have limited their clinical application. Recently, increasing attention has concentrated on the polysaccharides from natural plant and animal sources for diabetes. In order to illustrate the pharmaceutical activity of polysaccharides as natural hypoglycemic agents, polysaccharides isolated from Astragalus, oyster mushroom, and Yacon were evaluated for their inhibitory effects on α-glucosidase. Polysaccharides were extracted and purified from Astragalus, Oyster mushroom, and Yacon with hot water at 90 °C for 3 h, respectively. The total sugar content of the polysaccharide was determined by the phenol-sulfuric acid method. The α-glucosidase inhibitory activity was measured by the glucose oxidase method. The results exhibited that the inhibitory effects on α-glucosidase were in decreasing order, Astragalus > oyster mushroom > Yacon. The α-glucosidase inhibition percentage of Astragalus polysaccharide and oyster mushroom polysaccharide were over 40% at the polysaccharide concentration of 0.4 mg·mL(-1). The IC50 of Astragalus polysaccharide and oyster mushroom polysaccharide were 0.28 and 0.424 mg·mL(-1), respectively. The information obtained from this work is beneficial for the use polysaccharides as a dietary supplement for health foods and therapeutics for diabetes. PMID:24863354

  16. Effect of extraction method on structure and antioxidant activity of Hohenbuehelia serotina polysaccharides.

    Science.gov (United States)

    Li, Xiaoyu; Wang, Lu

    2016-02-01

    The impacts of four extraction methods (hot water, enzyme assistance, ultrasonic assistance and ultrasonic-enzyme assistance) on the extraction yields, preliminary structure and antioxidant activities of the Hohenbuehelia serotina polysaccharides (HW-HSP, EA-HSP, UA-HSP and UEA-HSP) were systematically investigated. The yield of the polysaccharides (20.70±0.17%) obtained by ultrasonic-enzyme assistance was higher than the polysaccharides by other methods'. Four kinds of polysaccharides possessed the different preliminary structural characteristics including molecular weight distributions, monosaccharide compositions, crystallization and spiral structures, while different surface morphology. Through the measurements of antioxidant activities in vitro, UEA-HSP exhibited the most significant scavenging capacities on non-physiological ABTS free radicals and physiological hydroxyl radicals. These data showed that ultrasonic-enzyme assistance was more beneficial to enhance the extraction yields of the polysaccharides, and obtain higher bioactive polysaccharides. The results also suggested that H. serotina polysaccharides possessed potential healthcare application in food field due to their antioxidant activities.

  17. Salt Effect on the Antioxidant Activity of Red Microalgal Sulfated Polysaccharides in Soy-Bean Formula

    Directory of Open Access Journals (Sweden)

    Ariela Burg

    2015-10-01

    Full Text Available Sulfated polysaccharides produced by microalgae, which are known to exhibit various biological activities, may potentially serve as natural antioxidant sources. To date, only a few studies have examined the antioxidant bioactivity of red microalgal polysaccharides. In this research, the effect of different salts on the antioxidant activities of two red microalgal sulfated polysaccharides derived from Porphyridium sp. and Porphyridium aerugineum were studied in a soy bean-based infant milk formula. Salt composition and concentration were both shown to affect the polysaccharides’ antioxidant activity. It can be postulated that the salt ions intefer with the polysaccharide chains’ interactions and alter their structure, leading to a new three-dimensional structure that better exposes antiooxidant sites in comparison to the polysaccharide without salt supplement. Among the cations that were studied, Ca2+ had the strongest enhancement effect on antioxidant activities of both polysaccharides. Understanding the effect of salts on polysaccharides’ stucture, in addition to furthering knowledge on polysaccharide bioactivities, may also shed light on the position of the antioxidant active sites.

  18. Olive Pomace, a Source for Valuable Arabinan-Rich Pectic Polysaccharides

    Science.gov (United States)

    Coimbra, Manuel A.; Cardoso, Susana M.; Lopes-da-Silva, José A.

    Cell wall polysaccharides account for nearly one third of olive pomace dry matter produced by the environment friendly biphasic system. These polysaccharides are mainly cellulose, glucuronoxylans, and arabinan-rich pectic polysaccharides, in equivalent proportions. The structural features of pectic polysaccharides are unique concerning the arabinan moiety due to the occurrence of a β-(1→5)-terminally-linked arabinose residue. This odd feature tends to disappear with olive ripening and can be used as a diagnostic tool in the evaluation of the stage of ripening of this fruit, as well as a marker for the presence of olive pulp in matrices containing pectic polysaccharides samples. These pectic polysaccharides have the ability to form elastic gels with calcium. The critical gelling calcium and galacturonic acid concentrations are higher than that observed for commercial citrus low-methoxyl pectic material. Nevertheless, they present a syneresis occurring for much higher calcium concentration and, consequently, show a much larger zone in which homogeneous gels are formed. In addition, olive pomace pectic polysaccharides gels are more resistant to temperature than the low-methoxyl pectin/calcium gels. These properties show that olive pomace can be a potential source of gelling pectic material with useful properties for particular applications.

  19. Antioxidant and anticoagulant activity of sulfated polysaccharide from Gracilaria debilis (Forsskal).

    Science.gov (United States)

    Sudharsan, Sadhasivam; Subhapradha, Namasivayam; Seedevi, Palaniappan; Shanmugam, Vairamani; Madeswaran, Perumal; Shanmugam, Annaian; Srinivasan, Alagiri

    2015-11-01

    Sulfated polysaccharide was isolated from Gracilaria debilis and purified through gel chromatography and their molecular weight was determined through AGE and PAGE. The total sugars in the crude, fractionated and purified polysaccharide were estimated as 52.65%, 59.70% and 67.60%, respectively. The ash and moisture content of crude and purified polysaccharide was found to be 14.2% and 23.5% and the polysaccharide was free from protein contamination. The sulfate and uronic acid contents in the crude, fractionated and purified were estimated as 14.08%, 15.33% and 16.01% and 10.12%, 13.56%, 16.70%. The elemental composition including carbon (crude - 23.12%, purified - 21.05%), hydrogen (crude - 3.4%, purified - 4.13%) and nitrogen (crude - 1.22%, purified - 0.56%) were also analyzed. The anticoagulant activity of the sulfated polysaccharide through APTT and PT was estimated at 14.11 and 8.23IU/mg. The purified polysaccharide with the molecular mass of 20kDa showed highest antioxidant activity (38.57%, 43.48% and 38.88%) in all the assays tested such as DPPH hydroxyl radical, superoxide radical, hydroxyl radical scavenging activities and the structural property was analyzed through FT-IR and (1)H NMR spectrum. The results together suggest that the isolated low molecular weight sulfated polysaccharide will demonstrate as a enormously available alternative natural source of antioxidant for industrial uses.

  20. Antioxidant and anticoagulant activity of sulfated polysaccharide from Gracilaria debilis (Forsskal).

    Science.gov (United States)

    Sudharsan, Sadhasivam; Subhapradha, Namasivayam; Seedevi, Palaniappan; Shanmugam, Vairamani; Madeswaran, Perumal; Shanmugam, Annaian; Srinivasan, Alagiri

    2015-11-01

    Sulfated polysaccharide was isolated from Gracilaria debilis and purified through gel chromatography and their molecular weight was determined through AGE and PAGE. The total sugars in the crude, fractionated and purified polysaccharide were estimated as 52.65%, 59.70% and 67.60%, respectively. The ash and moisture content of crude and purified polysaccharide was found to be 14.2% and 23.5% and the polysaccharide was free from protein contamination. The sulfate and uronic acid contents in the crude, fractionated and purified were estimated as 14.08%, 15.33% and 16.01% and 10.12%, 13.56%, 16.70%. The elemental composition including carbon (crude - 23.12%, purified - 21.05%), hydrogen (crude - 3.4%, purified - 4.13%) and nitrogen (crude - 1.22%, purified - 0.56%) were also analyzed. The anticoagulant activity of the sulfated polysaccharide through APTT and PT was estimated at 14.11 and 8.23IU/mg. The purified polysaccharide with the molecular mass of 20kDa showed highest antioxidant activity (38.57%, 43.48% and 38.88%) in all the assays tested such as DPPH hydroxyl radical, superoxide radical, hydroxyl radical scavenging activities and the structural property was analyzed through FT-IR and (1)H NMR spectrum. The results together suggest that the isolated low molecular weight sulfated polysaccharide will demonstrate as a enormously available alternative natural source of antioxidant for industrial uses. PMID:26424206

  1. Sulfated Polysaccharides in Marine Sponges: Extraction Methods and Anti-HIV Activity

    Directory of Open Access Journals (Sweden)

    Ana I. S. Esteves

    2011-01-01

    Full Text Available The extraction, fractionation and HIV-1 inhibition potential of polysaccharides extracted from three species of marine sponges, Erylus discophorus, Cliona celata and Stelletta sp., collected in the Northeastern Atlantic, is presented in this work. The anti-HIV activity of 23 polysaccharide pellets and three crude extracts was tested. Crude extracts prepared from Erylus discophorus specimens were all highly active against HIV-1 (90 to 95% inhibition. Cliona celata pellets showed low polysaccharide content (bellow 38.5% and almost no anti-HIV activity (<10% inhibition. Stelletta sp. pellets, although quite rich in polysaccharide (up to 97.3%, showed only modest bioactivity (<36% HIV-1 inhibition. Erylus discophorus pellets were among the richest in terms of polysaccharide content (up to 98% and the most active against HIV-1 (up to 95% inhibition. Chromatographic fractionation of the polysaccharide pellet obtained from a specimen of Erylus discophorus (B161 yielded only modestly active fractions. However, we could infer that the active molecule is most probably a high molecular weight sulfated polysaccharide (>2000 kDa, whose mechanism is possibly preventing viral attachment and entry (fusion inhibitor.

  2. Polysaccharide hydrogel combined with mesenchymal stem cells promotes the healing of corneal alkali burn in rats.

    Directory of Open Access Journals (Sweden)

    Yifeng Ke

    Full Text Available Corneal chemical burns are common ophthalmic injuries that may result in permanent visual impairment. Although significant advances have been achieved on the treatment of such cases, the structural and functional restoration of a chemical burn-injured cornea remains challenging. The applications of polysaccharide hydrogel and subconjunctival injection of mesenchymal stem cells (MSCs have been reported to promote the healing of corneal wounds. In this study, polysaccharide was extracted from Hardy Orchid and mesenchymal stem cells (MSCs were derived from Sprague-Dawley rats. Supplementation of the polysaccharide significantly enhanced the migration rate of primarily cultured rat corneal epithelial cells. We examined the therapeutic effects of polysaccharide in conjunction with MSCs application on the healing of corneal alkali burns in rats. Compared with either treatment alone, the combination strategy resulted in significantly better recovery of corneal epithelium and reduction in inflammation, neovascularization and opacity of healed cornea. Polysaccharide and MSCs acted additively to increase the expression of anti-inflammatory cytokine (TGF-β, antiangiogenic cytokine (TSP-1 and decrease those promoting inflammation (TNF-α, chemotaxis (MIP-1α and MCP-1 and angiogenesis (VEGF and MMP-2. This study provided evidence that Hardy Orchid derived polysaccharide and MSCs are safe and effective treatments for corneal alkali burns and that their benefits are additive when used in combination. We concluded that combination therapy with polysaccharide and MSCs is a promising clinical treatment for corneal alkali burns and may be applicable for other types of corneal disorder.

  3. Chemical Composition and Antioxidant Activities of Three Polysaccharide Fractions from Pine Cones

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    Pu Wang

    2012-11-01

    Full Text Available The traditional method of gas chromatography-mass spectrometry for monosaccharide component analysis with pretreatment of acetylation is described with slight modifications and verified in detail in this paper. It was then successfully applied to the quantitative analysis of component monosaccharides in polysaccharides extracted from the pine cones. The results demonstrated that the three pine cone polysaccharides all consisted of ribose, rhamnose, arabinose, xylose, mannose, glucose and galactose in different molar ratios. According to the recovery experiment, the described method was proved accurate and practical for the analysis of pine cone polysaccharides, meeting the need in the field of chemical analysis of Pinus plants. Furthermore; the chemical characteristics, such as neutral sugar, uronic acids, amino acids, molecular weights, and antioxidant activities of the polysaccharides were investigated by chemical and instrumental methods. The results showed that the chemical compositions of the polysaccharides differed from each other, especially in the content of neutral sugar and uronic acid. In the antioxidant assays, the polysaccharide fractions exhibited effective scavenging activities on ABTS radical and hydroxyl radical, with their antioxidant capabilities decreasing in the order of PKP > PAP > PSP. Therefore, although the polysaccharide fractions had little effect on superoxide radical scavenging, they still have potential to be developed as natural antioxidant agents in functional foods or medicine.

  4. Straightforward approach to graft bioactive polysaccharides onto polyurethane surfaces using an ionic liquid

    Energy Technology Data Exchange (ETDEWEB)

    Bigot, Sandra [Normandie Université, INSA de Rouen, CNRS UMR 6270 FR 3038, Avenue de l’université BP08, 76801 Saint-Etienne du Rouvray (France); Louarn, Guy [Institut des Matériaux Jean Rouxel (IMN), UMR 6502, CNRS-Université de Nantes, 2 rue de la Houssinière, BP 32229, 44322 Nantes (France); Kébir, Nasreddine, E-mail: nasreddine.kebir@insa-rouen.fr [Normandie Université, INSA de Rouen, CNRS UMR 6270 FR 3038, Avenue de l’université BP08, 76801 Saint-Etienne du Rouvray (France); Burel, Fabrice [Normandie Université, INSA de Rouen, CNRS UMR 6270 FR 3038, Avenue de l’université BP08, 76801 Saint-Etienne du Rouvray (France)

    2014-09-30

    Graphical abstract: - Highlights: • Development of a facile chemical process for PU surface derivatization. • Direct grafting of seaweed polysaccharides onto isothiocyanated PU surface. • Use of a selected ionic liquid as solvent and catalyst. - Abstract: Surface properties directly affect the performance of a material in a biological environment. In this study, the goal was to develop a simple procedure allowing the grafting of antibacterial polysaccharides onto biomedical grade polyurethanes (e.g. Tecothane{sup ®}). Thus, a straightforward chemical pathway involving an isothiocyanate–alcohol reaction in an ionic liquid (IL) was developed. PU isothiocyanted surfaces (PU–NCS) were first prepared by reacting p-phenylene diisothiocyanate with the surface urethane groups. Then, unmodified bioactive seaweed polysaccharides were directly grafted onto the surface, in mild conditions. The selected IL, i.e. 1-ethyl-3-methyl imidazolium phosphate, was of particular interest since this liquid worked as solvent for p-phenylene diisothiocyanate and the polysaccharides and as catalyst for the grafting reactions. Successful grafting of the different polysaccharides was attested by changes in the surface functional groups, using X-ray photoelectron spectroscopy (XPS). Atomic force microscopy (AFM) showed that polysaccharide grafting, slightly increased the surface roughness from 1.9 to more than 7 nm. Contact angle with water decreased from 88° (for native PU) to around 75° after polysaccharide grafting, attesting a more hydrophilic surface. This procedure would be transposed to the grafting onto PU surfaces of any macromolecule of interest bearing hydroxyl, thiol or amine groups.

  5. Evaluation of Macroalgae Sulfated Polysaccharides on the Leishmania (L. amazonensis Promastigote

    Directory of Open Access Journals (Sweden)

    Marcos Hikari Toyama

    2013-03-01

    Full Text Available The sulfated polysaccharides from Solieria filiformis (Sf, Botryocladia occidentalis (Bo, Caulerpa racemosa (Cr and Gracilaria caudata (Gc were extracted and extensively purified. These compounds were then subjected to in vitro assays to evaluate the inhibition of these polysaccharides on the growth of Leishmania (L. amazonensis promastigotes. Under the same assay conditions, only three of the four sulfated polysaccharides were active against L. amazonensis, and the polysaccharide purified from Cr was the most potent (EC50 value: 34.5 μg/mL. The polysaccharides derived from Bo and Sf demonstrated moderate anti-leishmanial activity (EC50 values of 63.7 μg/mL and 137.4 μg/mL. In addition, we also performed in vitro cytotoxic assays toward peritoneal macrophages and J774 macrophages. For the in vitro cytotoxicity assay employing J774 cells, all of the sulfated polysaccharides decreased cell survival, with CC50 values of 27.3 μg/mL, 49.3 μg/mL, 73.2 μg/mL, and 99.8 μg/mL for Bo, Cr, Gc, and Sf, respectively. However, none of the sulfated polysaccharides reduced the cell growth rate of the peritoneal macrophages. These results suggest that macroalgae contain compounds with various chemical properties that can control specific pathogens. According to our results, the assayed sulfated polysaccharides were able to modulate the growth rate and cell survival of Leishmania (L. amazonensis promastigotes in in vitro assays, and these effects involved the interaction of the sulfated polysaccharides on the cell membrane of the parasites.

  6. Antioxidant Activity and Characterization of One New Polysaccharide Obtained from Perigord Truffle (Tuber huidongense).

    Science.gov (United States)

    Chen, Yong-Feng; Jiang, Wen-Wen; Zhang, Shi-Qi; Kan, Jian-Quan; Liang, Yong

    2016-01-01

    As a medicinal and edible fungus parasitizing on the trees, Perigord Truffle (Tuber huidongense) is well known for its delicious taste, unique smell, and high medical value for healthcare. One new water-soluble nonstarch polysaccharide (PST-W with the yield of 0.41%) from Perigord Truffle (Tuber huidongense) was purified and identified on structural characteristics for the first time. The characterizations of PST-W were studied on physicochemical properties, main components of monosaccharide(s), and molecular structure. The monosaccharide compositions of PST-W were studied and identified as glucan, only containing D-glucoses with the molecular structure of [→6) α-D-Glcp (1 → 6)  α-D-Glcp (1→] n by methylation analysis and NMR. In the determination of total reducing capacity, the reducing abilities of polysaccharide extracts could be listed as vitamin C > PST-W > crude polysaccharides-3 > crude polysaccharides-2 > crude polysaccharides-1. All of PST-W, crude polysaccharides-2, and crude polysaccharides-3 were relatively good scavenger for 1,1-Diphenyl-2-picrylhydrazyl radical 2,2-Diphenyl-1-(2,4,6-trinitrophenyl)hydrazyl radicals with IC50 of 2.81, 4.17, and 3.44 mg/mL, respectively. However, O2 (-∙) clearing abilities of PST-W and crude polysaccharides were obviously weaker. The activities of total crude extract were the worst, indicating that the impurities might negatively affect the antioxidant activity. Thus, the separation and purification of polysaccharides were significant to increase the antioxidant activity in some degree. PMID:27446223

  7. Comparative Analysis of Polysaccharides from Two Ecological Types of Leymus chinensis

    Institute of Scientific and Technical Information of China (English)

    LI Jing-jing; BI Hong-tao; YAN Ji-hong; SUN Fang; FAN Sha-sha; CAO Gang; ZHOU Yi-fa; CHEN Xi-guang

    2012-01-01

    Leymus chinensis(Trin.) Tzvel.,widely distributed at eastern Eurasian steppe and divided into gray-green type and yellow-green type,has different stress resistance to environment.In the present study,the water-soluble polysaccharides from two ecotypes ofL.chinensis were analyzed in detail,and the differences between polysaccharides from the two ecotypes ofL.chinensis in the yield,monosaccharide composition,molecular weight and structure were clarified.The polysaccharides of L.chinensis were composed of both neutral and acidic polysaccharides.The neutral polysaccharides contained mannose,glucose,galactose,xylose and arabinose,and mainly consisted of β-1,4-Glcp,α-1,3-Galp and α-1,2-Xylp residues.The acidic polysaccharides contained mannose,rhamnose,glucuronic acid,galacturonic acid,glucose,galactose,xylose and arabinose.However,the yields,monosaccharides contents and the molecular weights of the polysaccharides from the two ecotypes of L.chinensis were different.Moreover,the resistance type(gray-green type) of L.chinensis contained a number of α-1,3-Manp and reducing end of β-Glcp residues,and much more O-methyl groups than normal type(yellow-green type) of L.chinensis.The differences of the polysaccharides of the two ecotypes ofL.chinensis might be due to the long-term environmental adaptability of plant,and the differences of the polysaccharides might influence the stress resistance of L.chinensis.

  8. Dietary supplementation with soluble plantain non-starch polysaccharides inhibits intestinal invasion of Salmonella Typhimurium in the chicken.

    Directory of Open Access Journals (Sweden)

    Bryony N Parsons

    Full Text Available Soluble fibres (non-starch polysaccharides, NSP from edible plants but particularly plantain banana (Musa spp., have been shown in vitro and ex vivo to prevent various enteric pathogens from adhering to, or translocating across, the human intestinal epithelium, a property that we have termed contrabiotic. Here we report that dietary plantain fibre prevents invasion of the chicken intestinal mucosa by Salmonella. In vivo experiments were performed with chicks fed from hatch on a pellet diet containing soluble plantain NSP (0 to 200 mg/d and orally infected with S.Typhimurium 4/74 at 8 d of age. Birds were sacrificed 3, 6 and 10 d post-infection. Bacteria were enumerated from liver, spleen and caecal contents. In vitro studies were performed using chicken caecal crypts and porcine intestinal epithelial cells infected with Salmonella enterica serovars following pre-treatment separately with soluble plantain NSP and acidic or neutral polysaccharide fractions of plantain NSP, each compared with saline vehicle. Bacterial adherence and invasion were assessed by gentamicin protection assay. In vivo dietary supplementation with plantain NSP 50 mg/d reduced invasion by S.Typhimurium, as reflected by viable bacterial counts from splenic tissue, by 98.9% (95% CI, 98.1-99.7; P<0.0001. In vitro studies confirmed that plantain NSP (5-10 mg/ml inhibited adhesion of S.Typhimurium 4/74 to a porcine epithelial cell-line (73% mean inhibition (95% CI, 64-81; P<0.001 and to primary chick caecal crypts (82% mean inhibition (95% CI, 75-90; P<0.001. Adherence inhibition was shown to be mediated via an effect on the epithelial cells and Ussing chamber experiments with ex-vivo human ileal mucosa showed that this effect was associated with increased short circuit current but no change in electrical resistance. The inhibitory activity of plantain NSP lay mainly within the acidic/pectic (homogalacturonan-rich component. Supplementation of chick feed with plantain NSP was

  9. Spontaneous bacterial peritonitis

    Institute of Scientific and Technical Information of China (English)

    Anastasios Koulaouzidis; Shivaram Bhat; Athar A Saeed

    2009-01-01

    Since its initial description in 1964, research has transformed spontaneous bacterial peritonitis (SBP) from a feared disease (with reported mortality of 90%) to a treatable complication of decompensated cirrhosis,albeit with steady prevalence and a high recurrence rate. Bacterial translocation, the key mechanism in the pathogenesis of SBP, is only possible because of the concurrent failure of defensive mechanisms in cirrhosis.Variants of SBP should be treated. Leucocyte esterase reagent strips have managed to shorten the 'tap-toshot' time, while future studies should look into their combined use with ascitic fluid pH. Third generation cephalosporins are the antibiotic of choice because they have a number of advantages. Renal dysfunction has been shown to be an independent predictor of mortality in patients with SBP. Albumin is felt to reduce the risk of renal impairment by improving effective intravascular volume, and by helping to bind proinflammatory molecules. Following a single episode of SBP, patients should have long-term antibiotic prophylaxis and be considered for liver transplantation.

  10. Antimicrobials for bacterial bioterrorism agents.

    Science.gov (United States)

    Sarkar-Tyson, Mitali; Atkins, Helen S

    2011-06-01

    The limitations of current antimicrobials for highly virulent pathogens considered as potential bioterrorism agents drives the requirement for new antimicrobials that are suitable for use in populations in the event of a deliberate release. Strategies targeting bacterial virulence offer the potential for new countermeasures to combat bacterial bioterrorism agents, including those active against a broad spectrum of pathogens. Although early in the development of antivirulence approaches, inhibitors of bacterial type III secretion systems and cell division mechanisms show promise for the future.

  11. Controls of Polysaccharide Chemistry on the Kinetics and Thermodynamics of Heterogeneous Calcium Carbonate Nucleation

    Science.gov (United States)

    Giuffre, A. J.; Han, N.; Dove, P. M.

    2011-12-01

    Polysaccharide fibrils control the orientation of calcium carbonate (CaCO3) biominerals. Good examples are found in the multilayered extracellular mucilaginous sheath of green algae and cyanobacteria and in specialized vesicles inside coccolithophorids. More complex organisms such as arthropods and mollusks form biomineralized exoskeletons and shells that consist of insoluble polysaccharides and soluble acid-rich proteins. In these structures, CaCO3 mineral orientation occurs along fibers of the polysaccharide chitin. This raises the question of whether polysaccharide chemistry has specific roles in directing biomineralization. The last three decades of research show that acidic proteins influence CaCO3 polymorph selection, crystallographic orientation, and nucleation and growth rates but little is known about the function of polysaccharides. In fact, polysaccharides are long considered an inert component of organic frameworks. In this experimental investigation, we test the hypothesis that polysaccharides have chemistry-specific influences on calcification by measuring the kinetics of calcite nucleation onto three types of polysaccharide films under controlled solution compositions. Characterized polysaccharides of simple repeating monomer sequences were chosen as model compounds to represent the major carbohydrates seen in microbial and calcifying environments: 1) alginic acid with carboxyl groups, 2) hyaluronic acid with alternating carboxyl and acetylamine groups, and 3) chitosan with amine and acetylamine groups. Biosubstrates were prepared by electrodeposition of these compounds as thin gel-like films onto gold-coated silicon wafers. Using a flow-through cell, heterogeneous nucleation rates of calcite were measured for a suite of supersaturation conditions. These rate data were compared to similar measurements for carboxyl- and hydroxyl-terminated self-assembled monolayers. Calcite nucleation rates onto the three polysaccharides vary by a factor of 400x

  12. Analgesic Activity of a Glucan Polysaccharide Isolated from Agaricus blazei Murill

    OpenAIRE

    Maria Leônia C. Gonzaga; Menezes, Thiago M. F.; de Souza, José R. R.; Nágila M. P. S. Ricardo; Ana L. P. Freitas; Sandra de A. Soares

    2013-01-01

    A water soluble polysaccharide and its selective precipitated fractions (F1, F2, and F3) were isolated from hot water extract of fruiting bodies of Agaricus blazei Murril known as Agaricus brasiliensis to evaluate the analgesic activity of the materials in Swiss mice. The isolated material and its fractions were characterized by two-dimensional COSY and HMQC spectra as β-(1→6)-α-(1→4)-glucan-bound-protein polysaccharide constituted mainly by β-(1→6) glucan. The glucan-protein polysaccharide a...

  13. Anti-inflammatory and immunomodulatory activities of polysaccharide from Chlorella stigmatophora and Phaeodactylum tricornutum.

    Science.gov (United States)

    Guzmán, S; Gato, A; Lamela, M; Freire-Garabal, M; Calleja, J M

    2003-06-01

    Crude polysaccharide extracts were obtained from aqueous extracts of the microalgae Chlorella stigmatophora and Phaeodactylum tricornutum. The crude extracts were fractionated by ion-exchange chromatography on DEAE-cellulose columns. The molecular weights of the polysaccharides in each fraction were estimated by gel filtration on Sephacryl columns. The crude polysaccharide extracts of both microalgae showed anti-inflammatory activity in the carrageenan-induced paw edema test. In assays of effects on the delayed hyper-sensitivity response, and on phagocytic activity assayed in vivo and in vitro, the C. stigmatophora extract showed immunosuppressant effects, while the P. tricornutum extract showed immunostimulatory effects. PMID:12820237

  14. Analysis of chemical components of shiitake polysaccharides and its anti-fatigue effect under vibration.

    Science.gov (United States)

    Li, Xiaoling; Zhang, Hongbo; Xu, Haibo

    2009-11-01

    The shiitake polysaccharides were obtained from shiitake mushroom. Four fractions were isolated from the polysaccharides using a Sephadex G-100 gel column. Chemical components of the two main fractions were determined by thin layer chromatography (TLC), and high performance liquid chromatography (HPLC). F1 was composed of rhamnose, glucose, and mannose. F3 was composed of xylose, mannose, arabinose and galactose. The obtained results still showed that administration of shiitake polysaccharides could improve muscle's comfortability of animals under a long period of vibration. The above findings might be applicable to studies of vibration ergonomics. PMID:19643126

  15. Antioxidant and Immunoregulatory Activity of Polysaccharides from Quinoa (Chenopodium quinoa Willd.)

    OpenAIRE

    Yang Yao; Zhenxing Shi; Guixing Ren

    2014-01-01

    The water-extractable (QWP) and the alkali-extractable (QAP) polysaccharides from quinoa (named QWP and QAP, respectively) and their four polysaccharide sub-fractions (QWP-1, QWP-2, QAP-1 and QAP-2), were isolated and purified by anion-exchange and gel filtration chromatography. QWP-1 and QWP-2 were composed of Rha, Ara, Gal and GalA. QAP-1 and QAP-2 were composed of Rha, Ara, Man, Gal and GalA. Antioxidant and immunoregulatory activities of the polysaccharides were evaluated. The results s...

  16. Component Analysis and Free Radicals Scavenging Activity of Physalis alkekengi L.Polysaccharide

    Institute of Scientific and Technical Information of China (English)

    CHENG Ying-kun; LI Lei; MENG Zhao-kun; HOU A-li; WU Yu-jie; TENG Li-rong

    2008-01-01

    A crude polysaccharide was extracted from Physalis alkekengi L.fruit.HPLC Was used for the component analysis of the polysaccharide.The results indicate that Physalis alkekengi L.polysaccharide(PAP) was composed of rharnnose,xylose,arabinose,galactose,and glucose.Free radicals scavenging activity of PAP was studied through 3 free radicals scavenging tests.PAP exhibited high scavenging effects on·OH and DPPH radicals,and both the scavenging rates were about 80%.The scavenging rate of·O2- radical was about 22%.

  17. INFLUENCES OF MOLECULAR WEIGHT AND BRANCHING PARAMETER OF LACQUER POLYSACCHARIDE ON THE GROWTH OF LEUCOCYTES

    Institute of Scientific and Technical Information of China (English)

    ZHANG Lina; DING Qiong

    1995-01-01

    A method of determining branching parameter of lacquer polysaccharide was established by acid-base back-titration of terminal uronic acid of branches. The branching factors obtained are in agreement with the values determined by colorimetric method with carbazole and the results estimated by using Zimm-Stockmayer equation from viscosity data. Influences of molecular weights and branching factors of five fractions of lacquer polysaccharide on the bioactivities were studied. The results show that the polysaccharides have bioactivities in motivating the growth of leucocytes, and the effect increases with the decrease of molecular weight and branching factor in the range studied(17×104>Mw>4×104).

  18. Isolation, purification, and immunomodulatory activity in vitro of three polysaccharides from roots of Cudrania tricuspidata

    Institute of Scientific and Technical Information of China (English)

    Lei Shi; Youli Fu

    2011-01-01

    Three water-soluble polysaccharides (CTPS-1A, CTPS2B, and CTPS-3A) were obtained from roots of Cudrania tricuspidata (Carr.) Bur. in this study. The homogeneity of polysaccharides was determined, and the average molecular weight, ultraviolet, infrared, monosaccharide composition, and methylation analyses were carried out Immunomodulatory activity assays in vitro showed that the three polysaccharides could directly stimulate the proliferation of mouse splenocytes alone or combining with concanavalin A or lipopolysaccharide. Furthermore, their stimulating activities were higher than that of the widely clinically used lentinan at optimal concentrations. CTPS1A and CTPS-2B also enhanced the pinocytic activity of mouse peritoneal macrophages.

  19. Study on the modulating effect of polysaccharide upon the mineralization of iron hydroxide

    Institute of Scientific and Technical Information of China (English)

    HUANG Jiangbo; SUN Zhenya

    2008-01-01

    To investigate the modulating effect of polysaccharide upon the mineralization of iron hydroxide, a series of simulative biomineralization experiments using dextran and chitosan as organic substrates were conducted in this paper. The results showed that iron hydroxide gel nucleated and grew in polysaccharide molecules, with the self-assemble effect of dextran or chitosan, the nanometer-sized akaganeite was formed. The shape, size and crystal structural type of iron oxyhydroxide formed from iron hydroxide gel depend on the type of polysaccharide and its concentrations.

  20. Biocatalytic cross-linking of pectic polysaccharides for designed food functionality

    DEFF Research Database (Denmark)

    Zaidel, Dayang Norulfairuz Abang; Meyer, Anne S.

    2012-01-01

    Recent research has demonstrated how cross-linking of pectic polysaccharides to obtain gel formation can be promoted by enzymatic catalysis reactions, and provide opportunities for functional upgrading of pectic polysaccharides present in agro-industrial sidestreams. This review highlights...... the mechanisms of formation of functional pectic polysaccharide cross-links, including covalent cross-links (notably phenolic esters and uronyl ester linkages) and non-covalent, ionic cross-links (which involve calcium and borate ester links). The treatise examines how such cross-links can be designed via...