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  • Electrochemical behavior of Polypyrrole/Chitosan composite coating on Ti metal for biomedical applications
    Carbohydr. Polym. (IF 4.811) Pub Date : 2018-01-17
    Bhavana Rikhari, S. Pugal Mani, N. Rajendran

    In the present work, the corrosion resistance performance and biocompatibility of Polypyrrole/Chitosan (PPy/CHI) composite coated Ti was studied. The deposition of composite coating was carried out by electropolymerization method. The deposited PPy/CHI composite coatings were different in morphology, structural, surface roughness and wettability compared PPy coated Ti. The presence of composite coating was confirmed by solid 13C NMR. The PPy/CHI composite coating showed enhanced microhardness and adhesion strength compared to the PPy coating. The corrosion protection ability of PPy/CHI composite coatings at various applied potentials was analyzed by dynamic electrochemical impedance spectroscopy (DEIS), exhibited higher impedance in all the potentials compared to uncoated and PPy coated Ti. The lower corrosion current density obtained for PPy/CHI-2 composite coating from polarization studies revealed increased corrosion protection ability in SBF solution. The stability of composite coating was confirmed by immersion studies. PPy/CHI-2 composite coating immersed in SBF solution enhances hydroxyapatite (HAp) formation.

    更新日期:2018-01-17
  • Fucosylated chondroitin sulfate is covalently associated with collagen fibrils in sea cucumber Apostichopus japonicus body wall
    Carbohydr. Polym. (IF 4.811) Pub Date : 2018-01-16
    Jun Wang, Yaoguang Chang, Fanxiu Wu, Xiaoqi Xu, Changhu Xue

    Fucosylated chondroitin sulfate (fCS) is the major carbohydrate constituent of sea cucumber. However, the distribution of fCS in the sea cucumber body wall has not been fully described. We addressed this in the present study employing Apostichopus japonicus as the material, a sea cucumber species with significant commercial importance. It was found that fCS was covalently attached to collagen fibrils via O-glycosidic linkages. Transmission electron microscopy analysis revealed that fCS precipitate was present in gap regions of collagen fibrils as roughly globular or ellipsoidal dots. The fCS dots arranged circumferentially around the fibrils with an axial repeat period that matched the periodicity of the fibrils. Physicochemical analysis indicated that the presence of fCS significantly increased the negative charge of the fibrils. These findings provide novel insight into fCS distribution in the sea cucumber body wall and its supramolecular organization with other macromolecules.

    更新日期:2018-01-17
  • Effect of retention rate of fluorescent cellulose nanofibrils on paper properties and structure
    Carbohydr. Polym. (IF 4.811) Pub Date : 2018-01-16
    Qijun Ding, Jinsong Zeng, Bin Wang, Wenhua Gao, Kefu Chen, Zhe Yuan, Jun Xu, Darong Tang

    In this work, we report a new characterization method using fluorescent cellulose nanofibrils to analyze retention and loss rates in the papermaking process. Cellulose nanofibrils (CNF) were isolated from chemical pulp by enzymatic pretreatment and used as a strengthening additive in sheet forming. The aim of this paper was to investigate its effects on flocculation, retention and loss rate and the physical and mechanical properties. CNF was subjected to fluorescent labeling with RBITC (Rhodamine B isothiocyanate), and the retention of fluorescent cellulose nanofibrils (FCNF) was analyzed by elemental analysis and fluorescence intensity. The retention and loss rate of the FCNF decreased with increasing the addition of FCNF. Laser Confocal Scanning Microscopy (LCSM) and Scanning Electron Microscope (SEM) images confirmed that FCNF can be evenly distributed in the paper. A thorough investigation of the relation between the retention rate and papersheet performance was conducted.

    更新日期:2018-01-17
  • Structural and physicochemical characterization of thermoplastic corn starch films containing microalgae
    Carbohydr. Polym. (IF 4.811) Pub Date : 2018-01-12
    María José Fabra, Marta Martínez-Sanz, L.G. Gómez-Mascaraque, Rafael Gavara, Amparo López-Rubio

    This work provides an in-depth analysis on how the addition of different microalgae species (Nannochloropsis, Spirulina and Scenedesmus) affected the structural and physicochemical properties of thermoplastic corn starch biocomposites. Structural characterization was conducted by combined SAXS/WAXS experiments and it was correlated with mechanical and barrier properties of the biocomposites. A water vapour permeability drop of ca. 54% was observed upon addition of the different microalgae species. The oxygen permeability and the mechanical properties of biocomposites containing Spirulina or Scenedesmus were not improved since the presence of microalgae hindered the re-arrangement and packing of the lamellar structure of starch polymeric chains, according to the SAXS results. Nannochloropsis caused a great reduction of the matrix rigidity and, the oxygen permeability was also improved. Therefore, all of these features make the Nannochloropsis biocomposites an alternative to generate biodegradable food packaging materials with the additional advantage that they can be easily scaled-up.

    更新日期:2018-01-12
  • Pd@HNTs-CDNS-g-C3N4: a novel heterogeneous catalyst for promoting ligand and copper-free Sonogashira and Heck coupling reactions, benefits from halloysite and cyclodextrin chemistry and g-C3N4 contribution to suppress Pd leaching
    Carbohydr. Polym. (IF 4.811) Pub Date : 2018-01-12
    Samahe Sadjadi, Majid M. Heravi, Masoumeh Malmir

    For the first time, a ternary hybrid system composed of halloysite nanotubes, HNTs, cyclodextrin nanosponges, CDNS, and g-C3N4 is prepared and used for immobilization of Pd(0) nanoparticles and development of a heterogeneous catalyst, Pd@HNTs-CDNS-g-C3N4 for promoting ligand and copper-free Sonogashira and Heck coupling reactions in aqueous media. HNT as a porous tubular clay with outstanding thermal, mechanical and textural properties can act as a support for immobilizing Pd nanoparticles. The role of CDNS can be explained on the base of its capability to form inclusion complexe with substrates and bringing them in the vicinity of the catalytic active sites. Regarding the role of g-C3N4 in catalysis, it is proved that its presence can suppress the Pd leaching dramatically. The contribution of each component as well as synergistic effect between them results in high catalytic activity and recyclability (up to 10 reaction runs) of the catalyst.

    更新日期:2018-01-12
  • 更新日期:2018-01-12
  • Transglutaminase-treated conjugation of sodium caseinate and corn fiber gum hydrolysate: Interfacial and dilatational properties
    Carbohydr. Polym. (IF 4.811) Pub Date : 2018-01-11
    Yan Liu, Michael J. Selig, Madhav P. Yadav, Lijun Yin, Alireza Abbaspourrad
    更新日期:2018-01-12
  • Investigations of benzo[a]pyrene encapsulation and Fenton degradation by starch nanoparticles
    Carbohydr. Polym. (IF 4.811) Pub Date : 2018-01-11
    Isabelle Delsarte, François Delattre, Catherine Rafin, Etienne Veignie

    Starch nanoparticles were produced by dialysis method from octenyl succinic anhydre (OSA) and 1,4-butane sultone (BS). The properties of the self-assembled nanoparticles were characterized by NMR spectroscopy (DOSY), fluorescence spectroscopy and dynamic light scattering (DLS). In order to investigate the formation of hydrophobic microdomains, the Nile Red dye was used as a fluorescent probe to evaluate the critical aggregation concentration (CAC) of modified starch in aqueous solution. The results show that the entrapment of the molecular guest was effective and only restricted by the solubility limit of the starch. Then, the modified starch was applied to solubilize benzo[a]pyrene (BaP) in view of degradation by Fenton process. Finally, it has been shown that 95% of BaP was degraded when it was encapsulated in OSA-BS-starch nanoparticles.

    更新日期:2018-01-12
  • Ion-Assisted Fabrication of Neutral Protein Crosslinked Sodium Alginate Nanogels
    Carbohydr. Polym. (IF 4.811) Pub Date : 2018-01-11
    Xing Wei, Hejian Xiong, Dongfang Zhou, Xiabin Jing, Yubin Huang

    Protein crosslinked nanogels which combine the merits of nanogels and the specific biological activity from protein have emerged as fascinating protein delivery systems. However, the fragility and low density of reactive group in proteins, especially low electric density of neutral proteins seriously limited the fabrication of protein crosslinked nanogels without affecting their bioactivities. Here, we demonstrated a facile ion-assisted method to fabricate neutral protein crosslinked nanogels. Oxidized sodium alginate (OSA) with aldehyde groups and low viscosity was successfully synthesized, which could reversibly form nanogels via addition and removal of divalent cation. Subsequently, hemoglobin and myoglobin were used as representative neutral proteins to fabricate stable protein crosslinked OSA nanogels under the assist of divalent cation followed by in situ Schiff base formation between OSA and proteins. The mild fabrication condition guaranteed the structural integrity and bioactivity of proteins in the obtained protein crosslinked nanogels. This ion-assisted method was expected to bring a new opportunity for fabricating versatile functional biohybrid nanogels systems.

    更新日期:2018-01-12
  • A one-step approach to make cellulose-based hydrogels of various transparency and swelling degrees
    Carbohydr. Polym. (IF 4.811) Pub Date : 2018-01-11
    Hongjuan Geng

    This work reports a “one-step” approach to make cellulose-based hydrogels in NaOH/urea aqueous solution via mixing N,N′-methylene bisacrylamide (MBA) with cellulose solution at room temperature. The hydrogels were revealed to be formed by an addition reaction between the double bonds of MBA and the hydroxyl groups of cellulose. Two states of hydrogels, i.e. the freshly prepared hydrogels and the hydrogels at swelling equilibrium state in deionized water, were prepared. Water retention of the hydrogels can reach up to 330 g H2O/g dry hydrogel. The freshly prepared hydrogels showed increased mechanical strength and high transparency (94%) with the addition of MBA. The hydrogels at swelling equilibrium state displayed macroporous structures with the pore diameter up to 0.65 mm and showed significantly varied properties with various amount of MBA. The obtained hydrogel could be used as a good blank template for the functionalization of cellulose-based hydrogel.

    更新日期:2018-01-12
  • Revealing a novel natural bioflocculant resource from Ruditapes philippinarum: Effective polysaccharides and synergistic flocculation
    Carbohydr. Polym. (IF 4.811) Pub Date : 2018-01-11
    Jun Mu, Haijun Zhou, Yin Chen, Guangfeng Yang, Xia Cui

    A novel natural bioflocculant resource of Ruditapes philippinarum conglutination mud (RPM) with the effective flocculation components was firstly reported in this study. Experimental results showed that the maximum flocculation activity (FR) of RPM to kolin clay reached 86.7% in deionized water assay system and 91.8% in sea water assay system. RPM could flocculate marine microalgae Chlorella salina with a FR of 74.1%. The crude RPM polysaccharides extract(RPMP) were composed of 97.8% (w/w) polysaccharides and 2.2% (w/w) protein and the functional components of pure RPMP were firstly discovered to be two complex heteropolysaccharides of RPMP-1 and RPMP-2 with similar monosaccharides composition except glucose content. The molecular weights of RPMP-1 and RPMP-2 were 5.7 kDa and 18.0 kDa, respectively. It is interesting to find that RPMP-1 and RPMP-2 exhibited synergistic flocculation activity of 65.6% at a mass ratio of 2:1 as in crude RPMP, suggesting the original proportion is significant to synergistic flocculation.

    更新日期:2018-01-12
  • Heterogeneous in situ polymerization of Polyaniline (PANI) nanofibers on cotton textiles: Improved electrical conductivity, electrical switching, and tuning properties
    Carbohydr. Polym. (IF 4.811) Pub Date : 2018-01-11
    Nadeeka D. Tissera, Ruchira N. Wijesena, Samantha Rathnayake, Rohini M.de Silva, K.M. Nalin de Silva
    更新日期:2018-01-12
  • Proton exchange membrane based on chitosan and solvent-free carbon nanotube fluids for fuel cells applications
    Carbohydr. Polym. (IF 4.811) Pub Date : 2018-01-11
    Jie Wang, Chunli Gong, Sheng Wen, Hai Liu, Caiqin Qin, Chuanxi Xiong, Lijie Dong
    更新日期:2018-01-12
  • Structural elucidation of a pectic polysaccharide from Fructus Mori and its bioactivity on intestinal bacteria strains
    Carbohydr. Polym. (IF 4.811) Pub Date : 2018-01-11
    Saijuan Li, Meixia Li, Han Yue, Lishuang Zhou, Lulin Huang, Zhenyun Du, Kan Ding

    Many studies suggested that polysaccharides could impact on the gut microbiota. To discover new polysaccharides which influence intestinal beneficial bacteria, a pectin polysaccharide FMP-6-S2 with an average molecular weight of 86.83 kDa was purified from Fructus Mori. The monosaccharide residue analysis indicated that FMP-6-S2 was composed of rhamnose, galacturonic acid, galactose and arabinose in a molar ratio of 30.86: 24.78: 28.70: 15.61. The backbone of FMP-6-S2 contained 1, 4-linked α-GalpA and 1, 2-linked α-Rhap with branches substituted at C-4 position of rhamnose. The branches were composed of 1, 4-linked β-Galp, terminal (T) − and 1, 3, 6-linked β-Galp, T- and 1, 5-linked α-Araf. Bioactivity test results suggested that FMP-6-S2 and its degraded product could promote growth of intestinal bacteria, B. thetaiotaomicron, which is a dominate strain in the gut of human to benefit intestinal mucosa. These results suggested that FMP-6-S2 and its degraded product might improve human wellness by modulating B. thetaiotaomicron.

    更新日期:2018-01-12
  • Investigation of OH bond energy for chemically treated alfa fibers
    Carbohydr. Polym. (IF 4.811) Pub Date : 2018-01-11
    Arwa Turki, Asma El Oudiani, Slah Msahli, Faouzi Sakli

    This work aims to study the hydrogen bond energy and distance for different samples of alfa fibers treated with thymol. The treatment duration and thymol concentration were varied and seem to have a great influence on infrared band intensities and positions. The number of hydrogen bonds is related to the infrared band intensity, whereas their energy and distance depend on the infrared band position. It was proven that the free hydroxyl groups are weakened and tend to disappear with fiber treatment. It is the same for intermolecular hydrogen bands between cellulosic chains that present a decrease in both intensity and frequency. The two intramolecular hydrogen bands increase in intensity but exhibit different behaviors regarding the calculated energy: while the band at 3268 cm−1 is weakened and shifted to higher wavenumbers, that at 3338 cm−1 keeps the same peak position and energy.

    更新日期:2018-01-12
  • Application of response surface methodology to tailor the surface chemistry of electrospun chitosan-poly(ethylene oxide) fibers
    Carbohydr. Polym. (IF 4.811) Pub Date : 2018-01-11
    Peter Bösiger, Isabelle M.T. Richard, Luce LeGat, Benjamin Michen, Mark Schubert, René M. Rossi, Giuseppino Fortunato

    Chitosan is a promising biocompatible polymer for regenerative engineering applications, but its processing remains challenging due to limited solubility and rigid crystalline structure. This work represents the development of electrospun chitosan/poly(ethylene oxide) blend nanofibrous membranes by means of a numerical analysis in order to identify and tailor the main influencing parameters with respect to accessible surface nitrogen functionalities which are of importance for the biological activity as well as for further functionalization. Depending on the solution composition, both gradient fibers and homogenous blended fiber structures could be obtained with surface nitrogen concentrations varying between 0 and 6.4%. Response surface methodology (RSM) revealed chitosan/poly(ethylene oxide) ratio and chitosan molecular weight as the main influencing factors with respect to accessible nitrogen surface atoms and respective concentrations. The model showed good adequacy hence providing a tool to tailor the surface properties of chitosan/poly(ethylene oxide) blends by addressing the amount of accessible chitosan.

    更新日期:2018-01-12
  • Digestibility of fucosylated glycosaminoglycan from sea cucumber and its effects on digestive enzymes under simulated salivary and gastrointestinal conditions
    Carbohydr. Polym. (IF 4.811) Pub Date : 2018-01-11
    Longyan Zhao, Yujing Qin, Ruowei Guan, Wenqi Zheng, Jikai Liu, Jinhua Zhao

    The digestibility of fucosylated glycosaminoglycan (FG) and its effects on digestive enzymes were investigated using an in vitro digestion model. Results showed that the molecular weight and the reducing sugar content of FG were not significantly changed, and no free monosaccharides released from FG were detected after the salivary, gastric and intestinal digestion, indicating that both the backbone and the sulfated fucose branches of FG are resistant to be cleaved in the saliva and gastrointestinal tract environments. Furthermore, FG can dose-dependently inhibit digestive enzymes such as α-amylase, pepsin and pancreatic lipase in different degrees under the simulated digestion conditions due to the sulfate and carboxyl groups. These physiological effects of FG may help control the postprandial glucose concentration and have the potential in the prevention or treatment of reflux disease and obesity. The findings may provide information on the digestibility and beneficial physiological effects of FG as a potential natural product to promote human health.

    更新日期:2018-01-12
  • Novel in situ forming hydrogel based on xanthan and chitosan re-gelifying in liquids for local drug delivery
    Carbohydr. Polym. (IF 4.811) Pub Date : 2018-01-10
    Jinjian Huang, Youming Deng, Jianan Ren, Guopu Chen, Gefei Wang, Feng Wang, Xiuwen Wu

    Injectable hydrogels have been an attractive topic in biomaterials. However, during gelation in vivo, they are easy to disperse due to tissue exudates, thus leading to failure of controlled drug release. To solve this problem, we present a novel polysaccharide-based injectable hydrogel via self-crosslinking of aldehyde-modified xanthan (Xan-CHO) and carboxymethyl-modified chitosan (NOCC). The physical properties were optimized by adjusting the mass ratio of Xan-CHO and NOCC. Experiments revealed that this material exhibited the characteristics of self-healing, anti-enzymatic hydrolysis, biocompatibility and biodegradability. The releasing curve demonstrated stable release of BSA-FITC within 10 hours after injection in liquids. After incorporation with a vascular endothelial growth factor, there was an interaction between this biomaterial and the host, which accelerated the reconstruction of the abdominal wall in rats. Therefore, this injectable hydrogel, as a drug delivery system, can prevent drug outburst in a variety of settings and function as a tissue scaffold.

    更新日期:2018-01-11
  • Effect of dynamic high pressure on emulsifying and encapsulant properties of cashew tree gum
    Carbohydr. Polym. (IF 4.811) Pub Date : 2018-01-10
    Bruna Castro Porto, Marcelo Cristianini

    Dynamic high pressure (DHP) has been applied in the physical modification of biopolymers as polysaccharides, proteins and gums. It is known that DHP is able to promote degradation of polysaccharides (e.g. molecular weight reduction). However, few studies have assessed the effect of DHP on the emulsifying and encapsulating properties of polysaccharides. Thus, this study aimed to investigate the effect of DHP on the emulsifying (average droplet size and particle size distribution, optical and confocal scanning laser microscopy, rheology, zeta potential and electric conductivity, creaming index, and turbidity) and encapsulating (scanning electronic microscopy, flavor retention, average droplet size, and particle size distribution) properties of cashew tree gum (CG). The application of DHP process improved the emulsifying capacity of cashew tree gum (CG) by reducing the medium droplet size (D3,2 and D4,3), increasing the turbidity and improving the emulsion stability. However, no effect of DHP was observed on the encapsulating capacity of CG.

    更新日期:2018-01-11
  • Therapeutic roles of polysaccharides from Dendrobium Officinaleon colitis and its underlying mechanisms
    Carbohydr. Polym. (IF 4.811) Pub Date : 2018-01-10
    Jian Liang, Shuxian Chen, Jianhui Chen, Jizong Lin, Qingping Xiong, Yiqi Yang, Jun Yuan, Lian Zhou, Lian He, Shaozhen Hou, Shijie Li, Song Huang, Xiaoping Lai

    Polysaccharide, as a promising candidate to meet the medication requirement of ulcerative colitis (UC), is increasingly attracting extensive interest. Dendrobium officinale has been widely used to treat gastrointestinal sickness in the clinical treatment of Traditional Chinese Medicine. However, it remains largely unknown whether polysaccharides (DOPS) from Dendrobium officinale can treat UC. The purpose of this paper is to confirm therapeutic action of DOPS to UC and explored its underlying mechanisms. We noted that DOPS could dramatically improve clinical signs and symptoms, decrease mortality, alleviate colonic pathological damage, and reestablish the balance of pro- and anti-inflammatory cytokines in DSS-induced acute UC mice. Moreover, DOPS treatment could also markedly suppress the activation of NLRP3 inflammasome and β-arrestin1 in vivo and in vitro. This study showed that DOPS possesses appreciable therapeutic effect to treat experimental acute UC mice. Its mechanism could be related to inhibition of NLRP3 inflammasome and β-arrestin1 signaling pathways.

    更新日期:2018-01-10
  • Methylation analysis of polysaccharides: Technical Advice
    Carbohydr. Polym. (IF 4.811) Pub Date : 2018-01-10
    Ian M. Sims, Susan M. Carnachan, Tracey J. Bell, Simon F.R. Hinkley

    Glycosyl linkage (methylation) analysis is used widely for the structural determination of oligo- and poly-saccharides. The procedure involves derivatisation of the individual component sugars of a polysaccharide to partially methylated alditol acetates which are analysed and quantified by gas chromatography-mass spectrometry. The linkage positions for each component sugar can be determined by correctly identifying the partially methylated alditol acetates. Although the methods are well established, there are many technical aspects to this procedure and both careful attention to detail and considerable experience are required to achieve a successful methylation analysis and to correctly interpret the data generated. The aim of this article is to provide the technical details and critical procedural steps necessary for a successful methylation analysis and to assist researchers (a) with interpreting data correctly and (b) in providing the comprehensive data required for reviewers to fully assess the work.

    更新日期:2018-01-10
  • Extraction and characterization of arrowroot (Maranta arundinaceae L.) starch and its application in edible films
    Carbohydr. Polym. (IF 4.811) Pub Date : 2018-01-09
    Gislaine Ferreira Nogueira, Farayde Matta Fakhouri, Rafael Augustus de Oliveira
    更新日期:2018-01-10
  • Structural comparison, antioxidant and anti-inflammatory properties of fucosylated chondroitin sulfate of three edible sea cucumbers
    Carbohydr. Polym. (IF 4.811) Pub Date : 2018-01-06
    Jiaojiao Mou, Qiang Li, Xiaohui Qi, Jie Yang

    Three fucosylated chondroitin sulfate (fCS) were obtained from edible sea cucumbers Apostichopus japonicus, Stichopus chloronotus and Acaudina molpadioidea collected from China. fCS from Stichopus chloronotus was firstly reported. The detailed structures of fCSs, particularly the fucose branches, were investigated and compared. 1H and 13C NMR of the polysaccharide identified three sulfation patterns of fucose branches: 4-O-, 2,4-di-O, and 3,4-di-O-sulfation variously existed in different fCSs. The backbone structure was confirmed by the monosaccharide composition and two-dimensional NMR. Antioxidant properties of fCSs were evaluated by the scavenging abilities on 1,1-diphenyl-2-picrylhydrazyl, nitric oxide radicals and inhibition of lipid peroxidation. The results showed that their activities could be affected by the sulfation patterns of the fucose branches, and O-4 sulfation is particularly important for its activities. The anti-inflammatory assays of fCS-Am showed significant reduction of the carrageenan induced edema in a dose depended manner, which could be used as a potential antiallergic agent.

    更新日期:2018-01-06
  • Optimized extraction of pectin-like polysaccharide from Suaeda fruticosa leaves: Characterization, antioxidant, anti-inflammatory and analgesic activities
    Carbohydr. Polym. (IF 4.811) Pub Date : 2018-01-06
    Zeineb Mzoughi, Amal Abdelhamid, Christophe Rihouey, Didier Le Cerf, Abderrahman Bouraoui, Hatem Majdoub
    更新日期:2018-01-06
  • Combination of carbon nanotube and cyclodextrin nanosponge chemistry to develop a heterogeneous Pd-based catalyst for ligand and copper free C-C coupling reactions
    Carbohydr. Polym. (IF 4.811) Pub Date : 2018-01-06
    Samahe Sadjadi, Majid M. Heravi, Maryam Raja

    Carbon nanotubes and cyclodextrin nanosponge were hybridized and used as a support for embedding Pd(0) nanoparticles and developing a novel and heterogeneous catalyst, Pd@CDNS-CNT, for promoting ligand and copper-free Sonogashira and Heck coupling reactions in aqueous media and mild reaction condition. Cyclodextrin nanosponge could contribute to catalysis through encapsulating the reagents and transferring them in the vicinity of Pd nanoparticles. The results established that the catalytic activity of Pd@CDNS-CNT was superior to those of Pd@CNT, Pd@CDNS and Pd@CNT + CDNS, indicating the synergism between the components of the hybrid system. Notably, various aryl halides including aryl iodide, bromide and chloride were useful substrates for the coupling reactions and affording the corresponding products in high to excellent yields in short reaction times. Moreover, the catalyst was recyclable up to six reaction runs with negligible Pd leaching.

    更新日期:2018-01-06
  • Synthesis and evaluation of thermo-rheological behaviour and ionotropic crosslinking of new gellan gum-alkyl derivatives
    Carbohydr. Polym. (IF 4.811) Pub Date : 2018-01-06
    Stefano Agnello, Fabio Salvatore Palumbo, Giovanna Pitarresi, Calogero Fiorica, Gaetano Giammona
    更新日期:2018-01-06
  • On the effects of hydroxyl substitution degree and molecular weight on mechanical and water barrier properties of hydroxypropyl methylcellulose films
    Carbohydr. Polym. (IF 4.811) Pub Date : 2018-01-06
    Caio G. Otoni, Marcos V. Lorevice, Márcia R. de Moura, Luiz H.C. Mattoso

    In line with the increasing demand for sustainable packaging materials, this contribution aimed to investigate the film-forming properties of hydroxypropyl methylcellulose (HPMC) to correlate its chemical structure with film properties. The roles played by substitution degree (SD) and molecular weight (Mw) on the mechanical and water barrier properties of HPMC films were elucidated. Rheological, thermal, and structural experiments supported such correlations. SD was shown to markedly affect film affinity and barrier to moisture, glass transition, resistance, and extensibility, as hydroxyl substitution lessens the occurrence of polar groups. Mw affected mostly the rheological and mechanical properties of HPMC-based materials. Methocel® E4 M led to films featuring the greatest tensile strength (ca., 67 MPa), stiffness (ca., 1.8 GPa), and extensibility (ca., 17%) and the lowest permeability to water vapor (ca., 0.9 g mm kPa−1 h−1 m−2). These properties, which arise from its longer and less polar chains, are desirable for food packaging materials.

    更新日期:2018-01-06
  • Design and development of guar gum based novel, superabsorbent and moisture retaining hydrogels for agricultural applications
    Carbohydr. Polym. (IF 4.811) Pub Date : 2018-01-06
    Nandkishore Thombare, Sumit Mishra, M.Z. Siddiqui, Usha Jha, Deodhari Singh, Gopal R. Mahajan

    The novel hydrogels were synthesized by grafting guar gum with acrylic acid and cross-linking with ethylene glycol di methacrylic acid (EGDMA). The synthesis of hydrogel was confirmed by characterization through 13C NMR, FTIR spectroscopy, SEM micrography, thermo-gravimetric analysis and water absorption studies under different solutions. Synthesized hydrogel (GG-AA-EGDMA) was confirmed to be biodegradable with half-life period of 77 days through soil burial biodegradation studies. The effects of hydrogel treatment on soil were evaluated by studying various physico-chemical properties of soil like bulk density, porosity, water absorption and retention capacity etc. The hydrogel which could absorb up to 800 ml water per gram, after addition to soil, improved its porosity, moisture absorption and retention capacity significantly. Water holding capacity of water increased up to 54% of its original and porosity also increased up to 9% of its original. The synthesized hydrogel revealed tremendous potential as soil conditioning material for agricultural applications.

    更新日期:2018-01-06
  • Production of cellulose nanoparticles from blue agave waste treated with environmentally friendly processes
    Carbohydr. Polym. (IF 4.811) Pub Date : 2018-01-06
    Eduardo Robles, Javier Fernández-Rodríguez, Ananda M. Barbosa, Oihana Gordobil, Neftali L.V. Carreño, Jalel Labidi
    更新日期:2018-01-06
  • Targeted delivery of SNX-2112 by polysaccharide-modified graphene oxide nanocomposites for treatment of lung cancer
    Carbohydr. Polym. (IF 4.811) Pub Date : 2018-01-05
    Xuan Liu, Xiaozhen Cheng, Fengzhe Wang, Longbao Feng, Yu Wang, Yanfang Zheng, Rui Guo

    Graphene oxide (GO) is a promising material for biomedical applications, particularly in drug delivery, due to its exceptional chemical and physical properties. In this work, an innovative GO-based carrier was developed by modifying GO with chitosan (CHI) to improve the biocompatibility, and followed by the conjugation of hyaluronic acid (HA), the target ligand for CD44, to realize the specific recognition of tumor cells and improve the efficiency of anti-tumor drug delivery. The resulting product GO-CHI-HA was loaded with an anti-cancer drug SNX-2112, which is the Hsp90 inhibitor. The total release amount and release rate of SNX-2112 were significantly higher in acidic condition than in physiological condition. GO-CHI-HA with a low concentration had little impact on the lysis of red blood cells (RBCs) and blood coagulation and showed low toxicity in A549 cells and NHBE cells. The GO-CHI-HA/SNX-2112 proved to be effective in inhibiting and killing A549 cells while having lower cytotoxicity against normal human bronchial epithelial cells (NHBE cells). Furthermore, in vivo toxicity of the materials towards vital organs in SD rats were also studied through histological examinations and blood property analyses, the results of which showed that although inflammatory response was developed in the short-term, GO-CHI-HA/SNX-2112 caused no severe long-term injury. Therefore, this drug delivery system showed great potential as an effective and safe drug delivery system with little adverse side effects for cancer therapy.

    更新日期:2018-01-06
  • Physicochemical characterization of polysaccharides from Chlorella pyrenoidosa and its anti-ageing effects in Drosophila melanogaster
    Carbohydr. Polym. (IF 4.811) Pub Date : 2018-01-05
    Yixuan Chen, Xiaoyan Liu, Linxiu Wu, Aijun Tong, Lina Zhao, Bin Liu, Chao Zhao

    The physicochemical characteristics and in vitro antioxidant and in vivo anti-ageing activities of partial purified Chlorella pyrenoidosa polysaccharides (PCPPs) were investigated. The building blocks of PCPPs were mainly composed of D-glucose, D-galactose and D-mannose. The average molecular weight of PCPPs was 9,950 Da. In vitro antioxidant activity assays showed that PCPPs could effectively scavenge hydroxyl, 1,1-diphenyl-2-picrylhydrazyl, and superoxide radicals, with stronger effect on hydroxyl radicals. Furthermore, the mean lifespan of the male and female Drosophila melanogaster was extended by 11.5% and 10.6%, respectively. This was accompanied by an increase in the total activity of the endogenous antioxidant enzymes, superoxide dismutase, glutathione peroxidase, and catalase in young or old D. melanogaster administered with PCPPs. Moreover, a gender-dependent difference was observed both in lifespan and antioxidant enzyme activities in D. melanogaster. The results indicated that C. pyrenoidosa polysaccharides are potential natural antioxidants in extending lifespan.

    更新日期:2018-01-06
  • Nanocrystalline cellulose as an eco-friendly reinforcing additive to polyurethane coating for augmented anticorrosive behavior
    Carbohydr. Polym. (IF 4.811) Pub Date : 2018-01-05
    M. Abd El-Fattah, Abdulraheim M.A. Hasan, Mohamed Keshawy, Ashraf M. El Saeed, O. Aboelenien

    Nanocrystalline cellulose (NCC) and micro-powdered cellulose (MPC) were extracted from rice straw by mechanical and alkali treatment methods, then characterized via infrared spectroscopy and dynamic light scattering. A series of polyurethane nanocrystalline cellulose composite (PNCCC) and polyurethane micro-powdered cellulose composite (PMPCC) coatings were prepared with various loading levels of NCC and MPC from 0.5 to 2.0 wt.%, and the coatings were applied onto the pretreated mild steel substrate at room temperature. The results showed that the NCC and MPC influenced positively the studied properties of the polyurethane coating; furthermore the most pronounced anticorrosive properties were obtained at 1 wt.% NCC and MPC, as confirmed by open circuit potential (OCP) study, electrochemical impedance spectroscopy (EIS) study and salt spray test. However, the optimum enhancement of mechanical properties was found at 1.5 wt.% loading level, after which further loading of NCC and MPC led to the reduction in the mechanical properties.

    更新日期:2018-01-06
  • Taste masking and rheology improvement of drug complexed with beta-cyclodextrin and hydroxypropyl-β-cyclodextrin by hot-melt extrusion
    Carbohydr. Polym. (IF 4.811) Pub Date : 2018-01-04
    Lorena F.B. Malaquias, Lívia C.L. Sá-Barreto, Daniel O. Freire, Izabel C.R. Silva, Kapish Karan, Thomas Durig, Eliana M. Lima, Ricardo N. Marreto, Guilherme M. Gelfuso, Tais Gratieri, Marcilio Cunha-Filho

    This study aimed to mask fluconazole (FLU) taste and improve its rheological properties by an efficient process of cyclodextrin complexation. For this, hot-melt extrusion (HME) was used to obtain extrudates composed of FLU, hydroxypropylcellulose, and one of two different cyclodextrins (β-cyclodextrin or hydroxypropyl-β-cyclodextrin) maintaining the drug:cyclodextrin molar ratio at 1:0.3 or 1:0.2, respectively. Samples were characterized by physicochemical tests, palatability using e-tongue and antifungal assays. Drug stability was preserved after HME, according to spectroscopy test (correlation coefficient >0.9) and HPLC-assay (100-107%). Flowability was improved in HME systems with compressibility of <12%. Similarly, floodability exhibited significant enhancement (dispersibility <10%). Whereas extrudates of FLU containing only the polymeric matrix led to a slow drug dissolution efficiency (18.6%) and a partial drug taste masking; extrudates containing cyclodextrin accelerated FLU dissolution (dissolution efficiency approx. 30%) and provided a complete drug taste masking. Moreover, HME process could produce drug complexes with high complexation efficiency and preserve its antifungal activity.

    更新日期:2018-01-05
  • Alginate-polymethacrylate hybrid hydrogels for potential osteochondral tissue regeneration
    Carbohydr. Polym. (IF 4.811) Pub Date : 2018-01-04
    P. Stagnaro, I. Schizzi, R. Utzeri, E. Marsano, M. Castellano

    Porous scaffolds based on alginate-polymethacrylate hybrid hydrogels intended for bone and cartilage regeneration were prepared through controlled calcium ions diffusion from an agar mould. The double interconnected network of such materials combines into a single porous structure maintained by both noncovalent crosslinks (calcium ions for alginate) and covalent crosslinks (polymethacrylate crosslinked by the addition of mixtures of mono and bifunctional monomers). The alginate component ensures the appropriate micro-environment to mimic the extra-cellular matrix, whereas the polymethacrylate improves the mechanical performances of the hybrid hydrogels, helping to overcome the mechanical limitations of the alginate component. Morphological characterization and porosity analysis of the hybrid scaffolds were assessed by scanning electron microscopy and micro-computed tomography. Relative concentration and distribution of calcium ions were evaluated by atomic absorption and dispersive X-ray analysis, respectively. Uniaxial compressive mechanical tests were conducted to evaluate the compressive elastic modulus of the hybrid hydrogels that was correlated with their swelling ratio and crosslinking degree. As was envisaged a much higher modulus (about seven times) was obtained for the hybrid Alg/HE hydrogel than with alginate alone.

    更新日期:2018-01-05
  • γ-Cyclodextrin-phenylacetic acid mesh as a drug trap
    Carbohydr. Polym. (IF 4.811) Pub Date : 2018-01-04
    Hyeong Sup Yu, Jae Min Lee, Yu Seok Youn, Kyung Taek Oh, Kun Na, Eun Seong Lee

    In this study, we developed a nanoporous biodegradable mesh, bioinspired by the spider web, which is prepared via electrospinning using γ-cyclodextrin (γ-CD) conjugated with phenylacetic acid (PA), named γ-CDP. The resulting γ-CDP has a microfibrous or microspherical shape and contains drug trap meshlike γ-CD pores. These γ-CDP micromeshes (microspheres or microfibers) enable efficient drug capture and drug transport into deep γ-CDP nanocompartments or out of the γ-CDP web, resulting in a driving domain for a 4-week drug release. When used to deliver chemotherapeutic agents to xenografted tumors, the γ-CDP implants caused nearly complete tumor regression for 4 weeks after single administration. This strategy of a drug trap biodegradable mesh (with low density) will make drug containers uniquely attractive for the development of therapeutic implants and functional biomedical devices.

    更新日期:2018-01-04
  • Cellulose nanocrystals (CNCs) with different crystalline allomorph for oil in water Pickering emulsions
    Carbohydr. Polym. (IF 4.811) Pub Date : 2018-01-04
    Xia Li, Jun Li, Jie Gong, Yishan Kuang, Lihuan Mo, Tao Song

    In recent years, nanocelluloses have attracted a lot of interests as promising stabilizers for Pickering emulsion particularly in food, cosmetics and pharmaceutics industries. In this work, two cellulose nanocrystals (named CNCs-I and CNCs-II) with different crystalline allomorph were investigated as stabilizers for oil-water Pickering emulsion. CNCs were prepared by sulfuric acid hydrolysis of unmodified and mercerized microcrystalline cellulose (MCC), respectively. CNCs-I was needle-like particles (length – 200 nm, width – 16.4 nm), while CNCs-II was individual granules (length – 18.8 nm, width – 10.9 nm) with ellipsoid shapes. Both CNCs had surface charge density higher than 0.1 e/nm2. Pickering emulsions stabilized by CNCs-I had larger emulsion ratio, two times smaller droplet size and superior performance of stability than CNCs-II. It is concluded that crystalline allomorph of CNCs played more dominating roles to the stabilization of Pickering emulsion than morphologies of CNCs themselves in this work, and CNCs-II is not the good candidates as stabilizer for Pickering emulsion compared to CNCs-I.

    更新日期:2018-01-04
  • Injectable and body temperature sensitive hydrogels based on chitosan and hyaluronic acid for pH sensitive drug release
    Carbohydr. Polym. (IF 4.811) Pub Date : 2018-01-03
    Wei Zhang, Xin Jin, Heng Li, Run-run Zhang, Cheng-wei Wu

    Hydrogels based on chitosan/hyaluronic acid/β-sodium glycerophosphate demonstrate injectability, body temperature sensitivity, pH sensitive drug release and adhesion to cancer cell. The drug (doxorubicin) loaded hydrogel precursor solutions are injectable and turn to hydrogels when the temperature is increased to body temperature. The acidic condition (pH 4.00) can trigger the release of drug and the cancer cell (Hela) can adhere to the surface of the hydrogels, which will be beneficial for tumor site-specific administration of drug. The mechanical strength, the gelation temperature, and the drug release behavior can be tuned by varying hyaluronic acid content. The mechanisms were characterized using dynamic mechanical analysis, Fourier transform infrared spectroscopy, scanning electron microscopy and fluorescence microscopy. The carboxyl group in hyaluronic acid can form the hydrogen bondings with the protonated amine in chitosan, which promotes the increase of mechanical strength of the hydrogels and depresses the initial burst release of drug from the hydrogel.

    更新日期:2018-01-04
  • Preparation and characterization of PVA/nanocellulose/Ag nanocomposite films for antimicrobial food packaging
    Carbohydr. Polym. (IF 4.811) Pub Date : 2018-01-03
    Muhammad Salman Sarwar, Muhammad Bilal Khan Niazi, Zaib Jahan, Tahir Ahmad, Arshad Hussain
    更新日期:2018-01-04
  • Homogeneous synthesis and characterization of chitosan ethers prepared in aqueous alkali/urea solutions
    Carbohydr. Polym. (IF 4.811) Pub Date : 2018-01-03
    Jinfeng Cao, Jun You, Lina Zhang, Jinping Zhou

    The etherification of chitosan dissolved in aqueous LiOH/KOH/urea solutions was conducted for the first time. The structure and solution properties of the chitosan ethers were characterized using FT-IR, NMR, SEC-LLS, elemental analysis, and ζ-potential measurement. Chitosan ethers with different degrees of substitution (DSs) were obtained by adjusting the molar ratio of the etherifying agent to N-acetylglucosamine unit (AGU) of chitosan. The total DS for methyl chitosan (MCh) increased from 1.17 to 2.25, and trimethyl chitosan (TMCh) was obtained with DSN-trimethyl as high as 0.48. The total DS for carboxymethyl chitosan (CMCh) was in the range 0.75–1.45. Both N-substitution and O-substitution were observed, and the single bond OH groups at C-6 displayed relative higher reactivity than the single bond OH groups at C-3. In comparison with the traditional methods and solvents, aqueous alkali/urea solutions proved to be a stable and more homogeneous medium for preparing chitosan ethers with higher DS through a one-step reaction.

    更新日期:2018-01-04
  • Photopolymerized Maleilated Chitosan/Thiol-terminated Poly (vinyl alcohol) hydrogels as Potential Tissue Engineering Scaffolds
    Carbohydr. Polym. (IF 4.811) Pub Date : 2018-01-03
    Yingshan Zhou, Shuyan Zhao, Can Zhang, Kaili Liang, Jun Li, Hongjun Yang, Shaojin Gu, Zikui Bai, Dezhan Ye, Weilin Xu

    Photocrosslinkable hydrogels composed of natural materials exhibit great application potential in tissue engineering scaffolds. However, weak formation and poor mechanical property can usually be a limitation. Herein, the photo-clickable thiol-ene hydrogels based chitosan were synthesized using photopolymerization of maleic chitosan (MCS) and thiol-terminated poly (vinyl alcohol) (TPVA) in the presence of a biocompatible photoinitiator. Rheological property and absorbing behavior of the MCS/TPVA hydrogels could be tailored by varying the amount of TPVA in the feed. There was strong intermolecular hydrogen bonding between the molecules of MCS and TPVA. Notably, the MCS/TPVA hydrogel (MT-3) exhibited rapid gelation behavior (<120 s), improved stiff (G' = ∼5500 Pa) and compressive strength (0.285 ± 0.014 MPa), which were important for hydrogel scaffolds, especially for injectable hydrogel scaffolds. Photocrosslinked MCS/TPVA hydrogels was cytocompatible and could promote the L929 cells attachment and proliferation, showing their potential as tissue engineering scaffolds.

    更新日期:2018-01-03
  • Chinese quince seed gum and poly (N,N-diethylacryl amide-co-methacrylic acid) based pH-sensitive hydrogel for use in drug delivery
    Carbohydr. Polym. (IF 4.811) Pub Date : 2018-01-03
    Ai-Jun Xie, Hui-Shuang Yin, Hua-Min Liu, Chun-Yan Zhu, Ya-Jie Yang

    In this investigation, a variety of innovative pH-sensitive polymers consisting of Chinese quince seed gum (CQSG) and poly (N,N-diethylacryl amide-co-methacrylic acid) were synthesized via free radical polymerization for controlled drug delivery. The resultant hydrogel polymers were characterized by scanning electron microscopy and X-ray diffraction, analyzed by Fourier-transform infrared spectroscopy, and confirmed with thermogravimetry. Results suggested the hydrogel polymers were composed of CQSG chains physically entangled in poly (N,N-diethylacryl amide-co-methacrylic acid) networks. Swelling properties of these hydrogels were strongly affected by the contents of CQSG and crosslinkers. The drug delivery applications of the hydrogels were evaluated using bovine serum albumin (BSA) as a model drug in vitro release. It was determined that BSA release from the hydrogels was pH-sensitive under simulated gastrointestinal conditions. All of these attributes imply that the new proposed CQSG/poly (N,N-diethylacryl amide-co-methacrylic acid) hydrogel polymers can be used as a good medium for oral delivery of proteinaceous drugs.

    更新日期:2018-01-03
  • Diurnal changes of glycogen molecular structure in healthy and diabetic mice
    Carbohydr. Polym. (IF 4.811) Pub Date : 2018-01-03
    Zhenxia Hu, Bin Deng, Xinle Tan, Hua Gan, Cheng Li, Sharif S. Nada, Mitchell A. Sullivan, Jialun Li, Xiaoyin Jiang, Enpeng Li, Robert G. Gilbert

    Glycogen is a complex branched glucose polymer functioning as a blood-sugar reservoir in animals. Liver glycogen β particles can bind together to form α particles, which have a slower enzymatic degradation to glucose. The linkage between β particles in α particles in diabetic liver breaks (is fragile) in dimethyl sulfoxide (DMSO), a H-bond disruptor, consistent with blood-sugar homeostasis loss in diabetes. We examined diurnal changes in the molecular structure of healthy and diabetic mouse-liver glycogen. Healthy mouse glycogen was fragile to DMSO during glycogen synthesis but not degradation; diabetic glycogen was always fragile. Two alternative mechanisms for this are suggested: healthy glycogen is fragile when formed and becomes stable during subsequent degradation, a process damaged in diabetes; alternatively, there are two types of glycogen: one compact but fragile and the other loose but non-fragile. This suggests potential types of diabetes drug targets through modifying the activities of glycogen synthesis enzymes.

    更新日期:2018-01-03
  • Synthesis, thermal properties and cell-compatibility of photocrosslinked cinnamoyl-modified hydroxypropyl cellulose
    Carbohydr. Polym. (IF 4.811) Pub Date : 2018-01-03
    Shinya Yano, Takumi Iwase, Naozumi Teramoto, Toshiaki Shimasaki, Mitsuhiro Shibata

    Biocompatibility of cinnamoyl-modified carbohydrate materials is not well-known, while they are attracting attention as a photoreactive material. In order to investigate biocompatible properties of cinnamoyl-modified carbohydrate, hydroxypropyl cellulose (HPC) was reacted with cinnamoyl chloride to yield cinnamoyl-modified HPC (HPC-C) for a cell proliferation test. HPC-Cs with three different degrees of substitution (DS) were prepared by changing a feed ratio of cinnamoyl chloride to HPC. The DS of the products ranged from 1.3 to 3.0 per one hydroxylpropyl anhydroglucose unit. Thermal analysis using DSC and TGA showed that the HPC-C with higher DS has a glass transition temperature and higher thermal stability. Ultraviolet (UV) light was irradiated on the HPC-C thin films, and changes in the UV-visible spectrum of the films were examined. In the course of UV irradiation, the absorbance at 280 nm was reduced. Fibroblast cells were cultured on the photocrosslinked HPC-C films, and cell growth was examined. The cell proliferation test revealed that the photocrosslinked HPC-C films have good compatibility with fibroblast cells.

    更新日期:2018-01-03
  • Soluble soybean polysaccharide/TiO2 bionanocomposite film for food application
    Carbohydr. Polym. (IF 4.811) Pub Date : 2018-01-02
    Davoud Salarbashi, Mohsen Tafaghodi, Bibi Sedigheh Fazly Bazzaz

    In the current study, a set of biodegradable soybean polysaccharide (SSPS) nanocomposites containing different ratios of TiO2 nanoparticles was characterized as new packaging system. X-ray diffraction (XRD) measurement showed that the crystalline structure of the TiO2 nanoparticles remained intact in the polysaccharide matrix and the surface of nanocomposites containing 1 to 3% TiO2 was observed morphologically uniform under scanning electron microscopy (SEM). Dynamic mechanical thermal analysis revealed that the magnitude of storage modulus was 3.62-fold higher in SPSS/TiO2 nanocomposites containing 7 wt. % of TiO2 than control SSPS indicating improvement in the physical properties of the film supposed to be utilized for food packaging. With respect to the concern over the safety of these nanocomposites, inductively coupled plasma-optical emission spectroscopy (ICP-OES) showed that no TiO2 was detected in bread samples covered by SSPS/TiO2 film and stored for 6 months. Similarly, the nanocomposite films only released a minuscule amount (21.05 ± 0.054 ppm) of TiO2 in water. TiO2 nanoparticles were found in the plasma membrane of epithelial cell line after long-term exposure (10-day) of these cells to large amounts of the free nanoparticles. SSPS/TiO2 nanocomposites showed excellent antimicrobial activity against Staphylococcus aureus PTCC 1431 (ATCC 25923), while neither anti-cancerous nor pro-cancerous activity was observed for these nanocomposites denoting their neutrality with respect to cancer suppression or progression in gastrointestinal tract. In conclusion, SSPS/TiO2 nanocomposites could be a promising packaging system for food industries’ objective regarding their physical characteristics, low rate of Ti transition, and low health risk.

    更新日期:2018-01-03
  • Oxidation pattern of curdlan with TEMPO-mediated system
    Carbohydr. Polym. (IF 4.811) Pub Date : 2018-01-02
    Rong Tang, Jie Hao, Ruijie Zong, Fangxia Wu, Yangyang Zeng, Zhenqing Zhang

    In this study, the TEMPO-mediated (TEMPO/NaBr/NaClO) oxidation pattern of curdlan was investigated through comprehensively structural analysis of the corresponding oxidized products. During the structural analysis, infrared spectroscopy (IR), nuclear magnetic resonance (NMR) spectroscopy, gel permeation chromatography tandem multiple angle laser scattering (GPC-MALS) and ultra-high performance liquid chromatography tandem quadrupole time of flight mass spectrometry (UHPLC-Q/TOF-MS) were applied. As a result, the homogenous β1-3 polyglucuronic acids (MW, 49.8, 29.8 and 7.0 kDa) were obtained with proper amount of oxidant (5.36 mmol NaClO) at various temperatures (4, 25, 50 °C), respectively. Compared to the oxidation of 1-4 linked glucan (starch and cellulose) with TEMPO-mediated system at same reaction conditions, higher degree of specific oxidation and less degradation were observed in that of 1-3 linked curdlan. The glycosylation at position 3 could stabilize the sugar ring, which inactivates the non-specific oxidation related hydroxyl groups on the sugar ring. Thus, the TEMPO-mediated system has higher selectivity to oxidize the primary hydroxyl groups of 1-3 linked curdlan and form polyglucuronic acid than those observed in the oxidation of starch and cellulose. In addition, same as those observed in previous work about starch, higher the temperature was used in the oxidation with TEMPO system, higher the activity of oxidant (NaClO solution) was, more non-specific oxidation occurred, and more the degradation were observed.

    更新日期:2018-01-03
  • Near-infrared emissive lanthanide hybridized nanofibrillated cellulose nanopaper as ultraviolet filter
    Carbohydr. Polym. (IF 4.811) Pub Date : 2018-01-02
    Bailiang Xue, Zhao Zhang, Yongchang Sun, Junjie Wang, Huie Jiang, Min Du, Congcong Chi, Xinping Li

    The lanthanide complexes [Yb(fac)3(H2O)2, Yb(tta)3(H2O)2, Nd(tta)3(H2O)2] functionalized nanofibrillated cellulose (Ln-NFC) nanopapers with near-infrared (NIR) luminescence and high transparency are rapidly fabricated after solvent exchange using a simple suction filtration film-making method. The effects of NFC and lanthanide complexes content on their photophysical properties of Ln-NFC nanopapers and their mechanism of UV filters are fully investigated. With increasing lanthanide complexes content in the Ln-NFC nanopaper, their transmittances are gradually decreased while their NIR luminescences are obviously increased. Yb-fac NFC nanopaper has high UVB block rate at 298 nm, whereas the high UVA block ratio of Ln-tta NFC nanopaper is observed at 345 nm. Ln-NFC nanopapers show a much higher photostability without decomposition under UV irradiation at 365 nm over 5 h. The emission spectra of the Ln-NFC nanopaper process the NIR luminescence of the corresponding lanthanide ions through the efficient triplet–triplet energy transfer process. Ln-NFC nanopapers can bring a brilliant future for UV filters, labeling fields and marking soft materials application.

    更新日期:2018-01-03
  • Self-assembly and rheological behaviors of intermacromolecular complexes consisting of oppositely charged fluorinated guar gums
    Carbohydr. Polym. (IF 4.811) Pub Date : 2018-01-02
    Chen Wang, Liewei Qiu, Tao Wang

    We synthesized fluorinated cationic/anionic guar gums (FCGG and FAGG) and characterized these species using Fourier transform infrared spectroscopy and 1H nuclear magnetic resonance spectroscopy. The degree of fluorine substitution of FCGG (0.26%) and FAGG (0.21%) was calculated by elemental analysis. In addition, we explored the self-assembly and rheological behaviors of FCGG-FAGG complexes by viscometry, scanning electron microscopy, light scattering, fluorescence spectroscopy, and rheometry. The maximum viscosity and molecular weights were observed with a FAGG:FCGG mass ratio of 7.0:3.0, denoted by COMP. Moreover, FAGG-FCGG interactions in COMP led to the lowest shape factor and critical associating concentration. Additionally, the relaxation time and crossover modulus of COMP (6.65 s and 0.90 Pa, respectively) were remarkably higher than those of FCGG and FAGG alone. Finally, viscoelastic hysteresis loops emerged for FAGG and COMP. The results suggested that the self-assembly behaviors of FAGG-FCGG were influenced by both ionic and fluorinated groups.

    更新日期:2018-01-03
  • The Effect of Nanocrystalline Cellulose on Flow Properties of Fiber Crop Aqueous Suspension
    Carbohydr. Polym. (IF 4.811) Pub Date : 2018-01-02
    Samira Gharehkhani, Seyed Farid Seyed Shirazi, Hooman Yarmand, Elham Montazer, Salim Newaz Kazi, Rushdan Ibrahim, Mehdi Ashjaei, Nurin Wahidah Binti Mohd Zulkifli, Sadegh Rahmati

    Nanocrystalline cellulose (NCC) a nature-based material, has gained significant attentions for its unique properties. The present study aims to investigate the flow behavior of cellulosic suspension containing non-wood pulp fibers and NCC, by means of rheological and pressure drop measurements. The NCC sample was prepared by sulfuric acid hydrolysis from Acacia mangium fibers. The rheological properties of kenaf/NCC suspensions were studied using viscosity and yield stress measurements. The pressure drop properties of the suspension flow were studied with respect to variation in flow velocity (0.4 m/s to 3.6 m/s) and the NCC concentration (70 mg/L and 150 mg/L). The pressure drop results showed that the pulp suspension containing 150 mg/L NCC had higher drag reduction than kenaf suspension alone. The present insights into the flow of pulp/NCC suspension provide a new data and promote the application of NCC in industries.

    更新日期:2018-01-03
  • Structural Characterization of Polysaccharides from Cabernet Franc, Cabernet Sauvignon and Sauvignon Blanc wines: anti-inflammatory activity in LPS stimulated RAW 264.7 cells
    Carbohydr. Polym. (IF 4.811) Pub Date : 2018-01-02
    Iglesias de Lacerda Bezerra, Adriana Rute Cordeiro Caillot, Lais Cristina Gusmão Ferreira Palhares, Arquimedes Paixão Santana Filho, Suely Ferreira Chavante, Guilherme Lanzi Sassaki

    The structural characterization of the polysaccharides and in vitro anti-inflammatory properties of Cabernet Franc (WCF), Cabernet Sauvignon (WCS) and Sauvignon Blanc (WSB) wines were studied for the first time in this work. The polysaccharides of wines gave rise to three fractions of polysaccharides, namely (WCF) 0.16%, (WCS) 0.05% and (WSB) 0.02%; the highest one was chosen for isolation of polysaccharides (WCF). It was identified the presence of mannan, formed by a sequence of α-D-Manp (1 → 6)-linked and side chains O-2 substituted for α-D-mannan (1 → 2)-linked; type II arabinogalactan, formed by (1 → 3)-linked β-D-Galp main chain, substituted at HO-6 by (1 → 6)-linked β-D-Galp side chains, and nonreducing end-units of arabinose 3-O-substituted; type I rhamnogalacturonan formed by repeating (1 → 4)-α-D-GalpA-(1 → 2)-α-L-Rhap groups; and traces of type II rhamnogalacturonan. The polysaccharide mixture and isolated fractions inhibited the production of inflammatory cytokines (TNF-α and IL-1β) and mediator (NO) in RAW 264.7 cells stimulated with LPS.

    更新日期:2018-01-03
  • Structural characterization, antioxidant and hepatoprotective activities of polysaccharides from Sophorae tonkinensis Radix
    Carbohydr. Polym. (IF 4.811) Pub Date : 2018-01-02
    Liangliang Cai, Shanshan Zou, Dengpan Liang, Libiao Luan

    In current study we present two polysaccharides, STRP1 and STRP2, purified from Sophorae tonkinensis Radix via column chromatography. Structural analyses indicated that STRP1 and STRP2 were consisted of mannose, rhamnose, glucuronic acid, glucose, galactose and arabinose in a similar molar ratio with main backbones of (1 → 3)-linked-α-D-Gal and (1 → 4)-linked-α-D-Glc, while average molecular weights were 1.30 × 104 and 1.98 × 105 Da, respectively. We observed a strong chelating ability on ferrous ions; substantial radical scavenging activities on DPPH, hydroxyl and superoxide anion radicals in vitro; and significant attenuation on acetaminophen-induced hepatic oxidative damage in mice for STRP1 and STRP2. The promising data on these polysaccharides showcase the need to further develop novel natural antioxidant and liver-protecting drugs.

    更新日期:2018-01-03
  • Interactions between microfibrillar cellulose and carboxymethyl cellulose in an aqueous suspension
    Carbohydr. Polym. (IF 4.811) Pub Date : 2018-01-02
    Deepa Agarwal, William MacNaughtan, Tim J. Foster

    New microstructures with interesting, unique and stable textures, particularly relevant to food systems were created by redispersing Microfibrillar cellulose (MFC). This paper reports the interactions between microfibrillar cellulose and carboxymethyl cellulose (CMC) in redispersed aqueous suspensions, by using rheological measurements on variable ratios of MFC/CMC and correlating these with apparent water mobility as determined by time domain NMR. MFC is a network of cellulose fibrils produced by subjecting pure cellulose pulp to high-pressure mechanical homogenisation. A charged polymer such as CMC reduces the aggregation of microfibrillar/fibre bundles upon drying. Small amplitude oscillatory rheological analysis showed viscoelastic gel-like behaviour of suspensions which was independent of the CMC content in the MFC suspension. A viscous synergistic effect was observed when CMC was added to MFC before drying, leading to improved redispersibility of the suspension. Novel measurements of NMR relaxation suggested that the aggregated microfibrillar/fibre bundles normally dominate the relaxation times (T2). The dense microfibrillar network plays an important role in generating stable rheological properties and controlling the mobility of the polymer and hence the apparent mobility of the water in the suspensions.

    更新日期:2018-01-03
  • 更新日期:2018-01-03
  • PEGylated chitosan nanoparticles with embedded bismuth sulfide for dual-wavelength fluorescent imaging and photothermal therapy
    Carbohydr. Polym. (IF 4.811) Pub Date : 2018-01-02
    Ke Wang, Jialang Zhuang, Yubing Liu, Maosheng Xu, Jingyuan Zhuang, Zuanguang Chen, Yen Wei, Yuanqing Zhang

    It is of great significance to construct multifunctional nanosystems for simultaneous imaging and therapy of cancer cells. Herein, PEGylated chitosan nanoparticles with embedded bismuth sulfide were facilely fabricated via reverse-microemulsion method for fluorescent imaging and photothermal therapy of HepG2 cells. The obtained BSA-Bi2S3-CG-PEG nanospheres revealed dual-wavelength fluorescence, which were spectrally isolated from the bioautofluorescence. Moreover, they demonstrated remarkable photothermal conversion efficiency and stability. Importantly, these small BSA-Bi2S3-CG-PEG nanoparticles shown a zeta potential of + 42.3 mV, which could rapidly get into HepG2 cells and locate in the cytoplasm and nuclei of cells. Based on their excellent photothermal effect and high cellular uptake, BSA-Bi2S3-CG-PEG nanoparticles could efficiently kill HepG2 cells under an 808 nm laser irradiation. This construction strategy can be used for preparation of fluorescent chitosan nanoparticles with other therapeutic agents embedded, which would provide a versatile platform for dual-wavelength fluorescent imaging guided therapy of cancer.

    更新日期:2018-01-03
  • Thermo-sensitive Injectable Glycol Chitosan-based Hydrogel for Treatment of Degenerative Disc Disease
    Carbohydr. Polym. (IF 4.811) Pub Date : 2018-01-02
    Zhengzheng Li, Hyeeun Shim, Myeong Ok Cho, Ik Sung Cho, Jin Hyun Lee, Sun-Woong Kang, Bosun Kwon, Kang Moo Huh

    The use of injectable hydrogel formulations have been suggested as a promising strategy for the treatment of degenerative disc disease to both restore the biomechanical function and reduce low back pain. In this work, a new thermo-sensitive injectable hydrogels with tunable thermo-sensitivity and enhanced stability were developed with N-hexanoylation of glycol chitosan (GC) for treatment of degenerative disc disease, and their physico-chemical and biological properties were evaluated. The sol-gel transition temperature of the hydrogels was controlled in a range of 23–56 °С, depending on the degree of hexanoylation and the polymer concentration. In vitro and In vivo tests showed no cytotoxicity and no adverse effects in a rat model. The hydrogel filling of the defective IVD site in an ex vivo porcine model maintained its stability for longer than 28 days. These results suggest that the hydrogel can be used as an alternative material for treatment of disc herniation.

    更新日期:2018-01-03
  • Effect of Punica granatum peel extracts on antimicrobial properties in Walnut shell cellulose reinforced Bio-thermoplastic starch films from cashew nut shells
    Carbohydr. Polym. (IF 4.811) Pub Date : 2017-12-30
    K. Harini, C. Chandra Mohan, K. Ramya, S. Karthikeyan, M. Sukumar

    The main aim of the present study is to extract and characterize cashew nut shell (CNS) starch and walnut shell cellulose (WNC) for development of cellulose reinforced starch films. Moreover, the extraction and characterization of pomegranate peel extract, for incorporation with CNS-WNC films, was investigated. CNS starch was examined to be a moderate amylose starch with 26.32 ± 0.43% amylose content. Thermal degradation temperature of CNS starch was found to be 310 °C. Walnut shell cellulose was found to have high crystallinity index of 72%, with two thermal degradation temperatures of 319 °C and 461 °C. 2% WN cellulose reinforced CNS starch films were examined to have good oxygen transfer rate, mechanical and physical properties. Thermal degradation temperature of CNS-WNC starch films were found to be at the range of 298–302 °C. Surface roughness of CNS-WNC starch films were found to be increasing with increase in concentration of cellulose in films. Hydroxymethylfurfurole, Benzene, 2-methoxy-1,3,4-trimethyl and 1,2,3-Propanetriol, 1-acetate were found to be major active compounds present in hydrophilic extracts of Punica granatum peels. 2% WN cellulose reinforced starch films infused with hydrophilic active compounds of pomegranate peel was examined to be having good active package properties.

    更新日期:2017-12-31
  • Anti-osteoporosis activity of a novel Achyranthes bidentata polysaccharide via stimulating bone formation
    Carbohydr. Polym. (IF 4.811) Pub Date : 2017-12-30
    Shaojie Zhang, Qian Zhang, Dawei Zhang, Changsheng Wang, Chunyan Yan
    更新日期:2017-12-31
  • Biomass-based magnetic fluorescent nanoparticles: One-step scalable synthesis, application as drug carriers and mechanism study
    Carbohydr. Polym. (IF 4.811) Pub Date : 2017-12-30
    Lei Li, Feijun Wang, Ziqiang Shao

    A biomass-based magnetic fluorescent nanoparticle (MFNPs) was successively in situ synthesized via a one-step high-gravity approach, which constructed by a magnetic core of Fe3O4 nanoparticles, the fluorescent marker of carbon dots (CDs), and shells of chitosan (CS). The obtained MFNPs had a 10 nm average diameter and narrow particle size distribution, low cytotoxicity, superior fluorescent emission and superparamagnetic properties. The encapsulating and release 5-fluorouracil experiments confirmed that the introduction of CS/CDs effectively improved the drug loading capacity. Mechanism and kinetic studies proved that: (i) the monolayer adsorption was the main sorption mode under the studied conditions; (ii) the whole adsorption process was controlled by intra-liquid diffusion mass transfer and governed by chemisorption; and (iii) the release process is controlled by Fickian diffusion. These results demonstrated this method to one-step continuously produce MFNPs and the construction of non-toxic nanostructure possessed great superiority in currently NDS, which would show high application value in targeted drug delivery, magnetic fluid hyperthermia treatment, magnetic resonance imaging (MRI), in vitro testing and relative research.

    更新日期:2017-12-31
  • Cellulose nanofiber-embedded sulfonated poly (ether sulfone) membranes for proton exchange membrane fuel cells
    Carbohydr. Polym. (IF 4.811) Pub Date : 2017-12-29
    Xianlin Xu, Rui Li, Chenxiao Tang, Hang Wang, Xupin Zhuang, Ya Liu, Weimin Kang, Lei Shi
    更新日期:2017-12-31
  • Comprehensive analysis of glycosaminoglycans from the edible shellfish
    Carbohydr. Polym. (IF 4.811) Pub Date : 2017-12-29
    Yusuke Okamoto, Kyohei Higashi, Robert J. Linhardt, Toshihiko Toida

    We have previously reported that the keratan sulfate (KS) disaccharide was branched to the C-3 position of glucuronate in chondroitin sulfate (CS)-E derived from the Mactra chinensis. We carried out the comprehensive disaccharide analysis of GAGs from 10 shellfish, Ruditapes philippinarum, Scapharca broughtonii, Mizuhopecten yessoensis, Turbo cornutus, Crassostrea nippona, Corbicula japonica, Mytilus galloprovincialis, Neptunea intersculpta, Pseudocardium sachalinense and Crassostrea gigas, to better understand the glycan structures in marine organisms. The contents of CS, heparan sulfate and hyaluronic acid and their compositions depend on the species of shellfish. Interestingly, a peak corresponding to a pentasaccharide containing KS disaccharide was observed when GAGs from T. cornutus was treated with chondroitinase (Chase) ACII but not Chase ABC. In addition, unidentified peaks were also observed when CS derived from R. philippinarum, S. broughtonii were treated with Chase ACII. These results suggest the presence of additional unidentified structure of CS in these shellfish.

    更新日期:2017-12-31
  • 更新日期:2017-12-31
Some contents have been Reproduced with permission of the American Chemical Society.
Some contents have been Reproduced by permission of The Royal Society of Chemistry.
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