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Carbohydrate Polymers

Lesego Maubane, Suprakas Sinha Ray, Kalala Jalama
In this study, butyl-etherified waxy and high amylose starches were melt-processed with biodegradable poly[(butylene succinate)-co-adipate] (PBSA) to improve the long-term stability of the starch-based materials. Butyl-etherification was believed to improve the compatibility of starch with PBSA matrix. Scanning electron microscopy results demonstrated that highly branched amylopectin structures in butyl-etherified starch have better chemical interaction with the PBSA matrix compared to linear amylose structures...
January 2, 2017: Carbohydrate Polymers
Obinna C Okeke, Joshua S Boateng
Composite wafers and films comprising HPMC and sodium alginate (SA) were formulated for nicotine (NIC) replacement therapy via the buccal route. Magnesium aluminium silicate (MAS) was added in different concentration ratios (0.25, 0.5, 0.75) to stabilize NIC and its effect on mechanical properties, internal and surface morphology, physical form, thermal properties, swelling, mucoadhesion, drug content and release behaviour of the formulations was investigated. MAS changed the physico-mechanical properties of the composite formulations causing a decrease in mechanical hardness, collapsed wafer pores, increased roughness of film surface, increase in crystallinity and decreased mucoadhesion of the wafers...
January 2, 2017: Carbohydrate Polymers
Behrooz Alizadeh Behbahani, Farideh Tabatabaei Yazdi, Fakhri Shahidi, Mohammad Ali Hesarinejad, Seyed Ali Mortazavi, Mohebbat Mohebbi
The effect of different extraction procedures on functional properties of mucilage extracted from Plantago major seed were investigated using response surface methodology. Extraction at 75°C, using 1:60 water:seed ratio at pH 6.8 was the best condition for maximum yield (15.18%), emulsion stability (67.4%), foam stability (88.4%), solubility (97.36%) and water absorption capacity (39.74g/g) of mucilage. At this optimum point, PMSM had, on average 82.85% carbohydrate, 76.79 mgGAE/gdry total phenol content, 97...
January 2, 2017: Carbohydrate Polymers
Peng-Fei He, Liang He, An-Qiang Zhang, Xing-Li Wang, Liang Qu, Pei-Long Sun
A water-soluble heteropolysaccharide (PUP60W-1) was purified from the hot water extract of sclerotia of P. umbellatus by chromatography with DEAE Sepharose Fast Flow and Sephacryl S200 High-Resolution. The primary structure of PUP60W-1 was elucidated by GC, GC-MS and NMR. PUP60W-1 was identified as a highly branched polysaccharide composed of fucose, glucose and galactose in a ratio of 1.0:0.9:13.3. The main repeating unit was identified as α-(1→6)-d-galactopyranan backbone with substitution of terminal α-galactopyranosyl residues at O-2 for two out of every three main chain galactose residues...
January 2, 2017: Carbohydrate Polymers
Fengyuan Huang, Xiaojie Wu, Yan Yu, Yanhua Lu, Qifan Chen
To eliminate the effect of humidity on nanopapers from nanocellulose, esters of CNCs (ECNCs) were synthesized via acylation of cellulose nanocrystals (CNCs) with fatty acids and Trifluoroacetic anhydride (TFAA). The structure information of ECNCs was confirmed via FTIR, degree of substitution (DS) determination, and XRD, respectively. With the increase of DS, the ECNCs could be dissolved in dichloromethane, which provided a ready way for fabrication of ECNCs films via casting/evaporation method. The tensile property, transmittance, hydrophobicity, thermal property and oxygen permeability of films were tested with universal tensile tester, UV-vis spectrophotometer, Contact angle tester, Simultaneous thermal analyzer and Oxygen permeability tester, respectively...
January 2, 2017: Carbohydrate Polymers
Palaniappan Seedevi, Meivelu Moovendhan, Shanmugam Viramani, Annian Shanmugam
The Sulfated polysaccharide was purified through anion-exchange and gel permeation column chromatography. The isolated sulfated polysaccharide from C. corticata contains 84% of carbohydrate, 0% of protein, 19.7% of ash and 29.4% of moisture was found. The carbon, hydrogen, nitrogen and sulfur content as 33.19%, 5.91%, 7.21% and 3.75%. The molecular weight of sulfated polysaccharide was found to be 43kDa. The sugar was composed of (90.11%), glucose (5.47%), xylose (2.30%) and mannose (2.12%). The structural feature of sulfated polysachharide was studied through FT-IR and (1)H NMR spectral analysis...
January 2, 2017: Carbohydrate Polymers
Peng Yu, Rui-Ying Bao, Xiao-Jun Shi, Wei Yang, Ming-Bo Yang
Graphene hydrogel has shown greatly potentials in bone tissue engineering recently, but it is relatively weak in the practical use. Here we report a facile method to synthesize high strength composite graphene hydrogel. Graphene oxide (GO), hydroxyapatite (HA) nanoparticles (NPs) and chitosan (CS) self-assemble into a 3-dimensional hydrogel with the assistance of crosslinking agent genipin (GNP) for CS and reducing agent sodium ascorbate (NaVC) for GO simultaneously. The dense and oriented microstructure of the resulted composite gel endows it with high mechanical strength, high fixing capacity of HA and high porosity...
January 2, 2017: Carbohydrate Polymers
Piming Ma, Tianfeng Shen, Long Lin, Weifu Dong, Mingqing Chen
Comb-like nanocrystal cellulose graft poly (d-lactide) (PDLA), i.e., NCC-g-PDLA nanohybrids were synthesized and compounded with poly (l-lactide) (PLLA) and poly (hydroxyalkanoate)s (PHA) to make fully biobased nanocomposites. Surprisingly, the complex viscosity of the PLLA/PHA melts was reduced by more than one order of magnitudes, viz. from 4000 to 100Pas by incorporation of 2-4wt% of the NCC-g-PDLA nanohybrids. Meanwhile, the crystallization of the PLLA component was accelerated by the NCC-g-PDLA nanohybrids due to the strong interaction between PDLA and PLLA macromolecules...
January 2, 2017: Carbohydrate Polymers
Suriya Palamae, Pongsathorn Dechatiwongse, Wanna Choorit, Yusuf Chisti, Poonsuk Prasertsan
A sequential two-step treatment with peracetic acid (PA) and alkaline peroxide (AP) at mild temperatures (20-35°C) removed more than 98% of the lignin from oil palm empty fruit bunch (EFB) fiber. For each kilogram of EFB fiber treated, 200-250g of a solids fraction and 120-170g of a precipitate fraction were recovered after the treatment. Subsequent enzymatic hydrolysis (45°C, 72h) of the recovered solids (excluding the precipitate) resulted in a glucose yield of 629.8±0.5g per kg of the original dry EFB biomass...
January 2, 2017: Carbohydrate Polymers
C Gaillard, Y Wang, R Covis, T Vives, Maud Benoît, T Benvegnu
The interaction between glycine betaine-based cationic surfactant and algal polysaccharide κ-carrageenan was studied by investigating the dilution effect of the surfactant/polymer assemblies driven by electrostatic interactions. Two aqueous solutions of cationic surfactant and κ-carrageenan at two molar ratios (3.5 and 0.8) diluted with factors of 5 and 10 times, were tested by various analytical methods including a multiscale observation by Transmission Electron Microscopy (TEM) and Laser Scanning Confocal Microscopy (LSCM) to understand the solution behavior of surfactant and oppositely charged polymer at both nano- and micrometer scale...
January 2, 2017: Carbohydrate Polymers
Jie Hao, Shuyi Xu, Naiyu Xu, Duxin Li, Robert J Linhardt, Zhenqing Zhang
Microcrystalline cellulose, a major component of cell wall of plants, is one of the most abundant natural materials, but the poor solubility of cellulose limits its applications. Cellulose is a linear glucan with exclusive β 1→4 linkage. Oxidation carried out with TEMPO-NaBr-NaClO system can selectively oxidize the C6 of glucose residues in cellulose. This modification improves polysaccharide solubility and other physicochemical properties. In this work, the impact of degree of oxidation on solubility, degree of crystallization, thermostability, molecular weight and the structures of the resulting oligosaccharide products of selectively oxidized cellulose were investigated using x-ray diffraction, thermogravimetric analysis, gel permeation chromatography-multiple angle laser light scattering and ultrahigh performance liquid chromatography-electrospray-quadrupole/time of flight-mass spectrometry, respectively...
January 2, 2017: Carbohydrate Polymers
Nushin Niknia, Rassoul Kadkhodaee
Gum tragacanth (GT) gels are usually formed by using chemical crosslinkers which cause safety concerns owing to their toxicity. This study introduces a novel and safe method for gelation of GT in the presence of small amounts of polyvinyl alcohol (PVA) followed by successive freeze-thaw (F-T) cycles. Gel formation was performed at two GT: PVA mixing ratios (1:1 and 3:1), four F-T consecutive cycles and two different thawing temperatures (25 and 5°C). Gel fraction, syneresis as well as mechanical properties and microstructural characteristics of the resultant gels were then studied...
January 2, 2017: Carbohydrate Polymers
Li-Chan Yang, Ching-Yi Lai, Wen-Chuan Lin
This study investigated the effects of a type II arabinogalactan from Anoectochilus formosanus (AGAF) on natural killer (NK) cell-mediated cytotoxicity and the possible underlying mechanisms. This study reported that sustained exposure to AGAF increased NK-92MI cell-mediated cytotoxicity in a time- and concentration-dependent manner, as characterized according to the cellular lactic dehydrogenase leakage from K562 leukemia cells. Additionally, antibody neutralization studies have reported that interferon (IFN)-γ, but not perforin or tumor necrosis factor-α, released by NK-92MI NK cells is crucial in enhancing cytotoxicity through an autocrine loop...
January 2, 2017: Carbohydrate Polymers
Ruyun Lou, Weiting Yu, Yizhe Song, Ying Ren, Huizhen Zheng, Xin Guo, Yunfei Lin, Guoyu Pan, Xiuli Wang, Xiaojun Ma
Galactose moieties are covalently coupled with sodium alginate to enhance liver-specific functions in microcapsules owing to the specific interaction between the galactose moieties and the asialoglycoprotein receptors (ASGPRs) of hepatocytes. In this study, galactosylated alginate (L-NH2-OH-alginate) based microcapsules with desirable stability and a suitable 3D microenvironment are designed and fabricated for primary hepatocyte applications. The designed L-NH2-OH-alginate is fabricated via the application of ethylenediamine grafted lactobionic acid (L-NH2) onto the hydroxyl groups of sodium alginate so that the negatively charged carboxyl groups intact in L-NH2-OH-alginate can effectively bond with Ca(2+) to form a stable three-dimensional gel network; a subsequent reaction with polycations forms a stable membrane of microcapsules...
January 2, 2017: Carbohydrate Polymers
Arn Mignon, Dries Devisscher, Geert-Jan Graulus, Birgit Stubbe, José Martins, Peter Dubruel, Nele De Belie, Sandra Van Vlierberghe
Polysaccharides, and especially alginate, can be useful for self-healing of cracks in concrete. Instead of weak electrostatic bonds present within calcium alginate, covalent bonds, by methacrylation of the polysaccharides, will result in mechanically stronger superabsorbent polymers (SAPs). These methacrylated alginate chains as backbone are combined with two acrylic monomers in a varying molar fraction. These SAPs show a moisture uptake capacity up to 110% their own weight at a relative humidity of 95%, with a negligible hysteresis...
January 2, 2017: Carbohydrate Polymers
Chih-Ying Chien, Yukiko Enomoto-Rogers, Akio Takemura, Tadahisa Iwata
Regioselectively substituted curdlan esters were synthesized by protecting the C6 primary hydroxyl group with a triphenylmethyl group followed by the acylation of the secondary hydroxyl groups at C2 and C4. The subsequent detritylation of C6 trityl group under acidic conditions revealed an unexpected acyl migration from C4 to C6. This unique acyl migration in curdlan was first observed, which haven't been reported in other polysaccharides such as cellulose. The rate of this migration was found to be dependent on the length of the acyl group, leading to the proposal of a new mechanism for this transformation...
January 2, 2017: Carbohydrate Polymers
Zarif Farhana Mohd Aris, Ryan M Bouldin, Margery G H Pelletier, Peter Gaines, Bridgette Budhlall, Ramaswamy Nagarajan
Microwave-assisted synthesis of a new class of polymeric surfactants based on polygalacturonic acid (PGA) is presented. PGA is water-insoluble and not surface-active under normal conditions. Single-step hydrophilic modification of PGA with taurine (2-aminoethane sulfonic acid) renders it surface-active. The modification can be carried out either using 1-ethyl-3-(3-dimethylaminopropyl) carbodiimide (EDCl) as a coupling agent or using microwave irradiation without a catalyst. Microwave irradiation significantly shortens reaction times and eliminates the need for a coupling agent...
January 2, 2017: Carbohydrate Polymers
Niédja Fittipaldi Vasconcelos, Judith Pessoa Andrade Feitosa, Francisco Miguel Portela da Gama, João Paulo Saraiva Morais, Fábia Karine Andrade, Men de Sá Moreira de Souza Filho, Morsyleide de Freitas Rosa
Bacterial cellulose (BC) is a polymer with interesting physical properties owing to the regular and uniform structure of its nanofibers, which are formed by amorphous (disordered) and crystalline (ordered) regions. Through hydrolysis with strong acids, it is possible to transform BC into a stable suspension of cellulose nanocrystals, adding new functionality to the material. The aim of this work was to evaluate the effects of inorganic acids on the production of BC nanocrystals (BCNCs). Acid hydrolysis was performed using different H2SO4 concentrations and reaction times, and combined hydrolysis with H2SO4 and HCl was also investigated...
January 2, 2017: Carbohydrate Polymers
Motonari Shibakami, Mitsugu Sohma
Acylation of paramylon, a storage polysaccharide of Euglena gracilis, using multiple acid anhydrides yielded thermoplastic paramylon mixed esters without significant depolymerization. DSC examination showed that the shorter the acyl chain, the higher both the melting and glass transition temperature of the ester. TG analyses revealed their higher thermostability with the 5% weight loss temperature of ∼330°C. Melt volume flow rate examination revealed that the longer the acyl chain, the higher the thermoplasticity of the ester and that the esters exhibited higher thermoplasticity than structurally analogous esters made from cellulose and curdlan...
January 2, 2017: Carbohydrate Polymers
Xueqiong Zhang, Lianghong Li, Chunfu Li, Hua Zheng, Haoyuan Song, Fuliang Xiong, Tong Qiu, Jin Yang
The delivery of combination chemotherapy by nanoscale platforms has been demonstrated to enhance cancer treatment in the clinic. Cisplatin (CDDP)-crosslinked, glutathione-sensitive, tumor-targeting micelles based on carboxymethyl chitosan were designed for synergistic cisplatin-doxorubicin (DOX) combination chemotherapy. In our study, DOX was conjugated to carboxymethyl chitosan through a disulfide bond, which was structurally characterized by (1)H NMR. The micelles formed by self-assembly were spherical, with the mean diameter of 274nm...
January 2, 2017: Carbohydrate Polymers
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