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Carbohydrate Polymers

Hamideh Molaei, Kambiz Jahanbin
A new water-soluble polysaccharide (CZGS-1) with molecular weight of 4860kDa and a specific optical rotation of +31.5° (c 1.0, H2O), was extracted from the gum exudate of Amygdalus scoparia Spach by hot water, following by purification with DEAE-cellulose A52 and Sephacryl S-400 HR columns. Monosaccharide composition analysis indicates that CZGS-1 was an arabino galactan including Rha, Ara, Xyl, and Gal with a relative molar ratio of 1.1:20:5.2:17.9. The uronic acid content of CZGS-1 was about 6%. Structural features of CZGS-1 was investigated by a combination of partial acid hydrolysis, methylation and GC-MS analysis, periodic acid oxidation and Smith degradation, FT-IR and NMR spectroscopy...
February 15, 2018: Carbohydrate Polymers
Y Liu, S Kong, H Xiao, C Y Bai, P Lu, S F Wang
A range of cellulose-based, ultra-lightweight pulp foams with different morphologies were prepared and reinforced with microfibrillated cellulose (MFC). By careful design of the pulp foam forming process, free-standing ultra-lightweight pulp foams were obtained through high velocity mixing and air/oven drying from cellulose fiber in the presence of surfactant, MFC, and retention aid. The effects of different types of fibers and surfactants on the air uptake volumes and mechanical properties of the foam were systematically investigated...
February 15, 2018: Carbohydrate Polymers
J Andrés Ortiz, Betty Matsuhiro, Paula A Zapata, Teresa Corrales, Fernando Catalina
A water soluble derivative in 98% yield with 23.1% incorporation of maleoyl groups was obtained by esterification of agarose with maleic anhydride. Graft copolymers were synthesized through vinyl groups of maleoylagarose with N-isopropylacrylamide using ceric ammonium nitrate or ammonium persulfate as initiator, by conventional method or microwave irradiation. High nitrogen content (4.6%) was obtained in the grafting process using ceric ammonium nitrate as initiator without microwave irradiation. Copolymers were characterized by FT-IR and NMR spectroscopies, TGA, DSC and morphological analysis by AFM and SEM microscopy, confirming the grafting of PNIPAAm onto polysaccharide backbone...
February 15, 2018: Carbohydrate Polymers
Kazuaki Ninomiya, Megumi Abe, Takayuki Tsukegi, Kosuke Kuroda, Yota Tsuge, Chiaki Ogino, Kentaro Taki, Tetsuya Taima, Joji Saito, Mitsugu Kimizu, Kiyoshi Uzawa, Kenji Takahashi
In the present study, we examined the efficacy of choline acetate (ChOAc, a cholinium ionic liquid))-assisted pretreatment of bagasse powder for subsequent mechanical nanofibrillation to produce lignocellulose nanofibers. Bagasse sample with ChOAc pretreatment and subsequent nanofibrillation (ChOAc/NF-bagasse) was prepared and compared to untreated control bagasse sample (control bagasse), bagasse sample with nanofibrillation only (NF-bagasse) and with ChOAc pretreatment only (ChOAc-bagasse). The specific surface area was 0...
February 15, 2018: Carbohydrate Polymers
Chao Qiu, Jinpeng Wang, Haoran Fan, Yuxiang Bai, Yaoqi Tian, Xueming Xu, Zhengyu Jin
In comparison with natural α- and β-cyclodextrin (CD), γ-CD has attracted much attention due to their large hydrophobic cavities, high water solubility, and bioavailability. However, the production of γ-CD is still rather expensive and time-consuming. To overcome the high cost and long induction time, pUC119 was selected as the gene expression vector, and the recombinant enzyme production time was reduced to 8h from 72h. Furthermore, for the first time, we have successfully produced γ-CD using β-CD by cyclodextrin opening reactions through the recombinant CGTase in the presence of maltose...
February 15, 2018: Carbohydrate Polymers
Sumesh Soman, Asha Susan Chacko, V S Prasad, P Anju, B S Surya, K Vandana
Nanotechnology involving cellulosic substrates has generated a great attention owing to their exceptional physical and chemical properties. Self-assembled nanostructures obtained from carbohydrate polymers are of interest in the biomedical field for the biocompatibility and non-toxic nature. In the present study modification of nano-fibrillated cellulose (NFC) synthesised from the husk fibers of Areca catechu nuts (AHF) was studied by controlled regio-selective amidation with oleylamine (OA) and characterized...
February 15, 2018: Carbohydrate Polymers
Zhen Zhang, Gilles Sèbe, Xiaosong Wang, Kam C Tam
pH-responsive poly(4-vinylpyridine) (P4VP) grafted cellulose nanocrystals (P4VP-g-CNC) were prepared by Surface-Initiated Atom Transfer Radical Polymerization (SI-ATRP) and subsequently used to stabilize gold nanoparticles (Au NPs) as efficient and recyclable nanocatalysts for the reduction of 4-nitrophenol (4NP). The presence of P4VP brushes on the CNC surface controlled the growth of Au NPs yielding smaller averaged diameter compared to Au NPs deposited directly on pristine CNC. The catalytic performances of pristine Au NPs, Au@CNC and Au@P4VP-g-CNC were compared by measuring the turnover frequency (TOF) for the catalytic reduction of 4NP...
February 15, 2018: Carbohydrate Polymers
Hongyu Liu, Cuiyun Liu, Shuge Peng, Bingli Pan, Chang Lu
A series of novel methyl cellulose (MC) composite films were prepared using polyethyleneimine reduced graphene oxide (PEI-RGO) as an effective filler for water vapor barrier application. The as-prepared PEI-RGO/MC composites were characterized by Fourier transform infrared spectroscopy, X-ray diffraction, thermogravimetric analysis, tensile test and scanning electron microscopy. The experimental and theoretical results exhibited that PEI-RGO was uniformly dispersed in the MC matrix without aggregation and formed an aligned dispersion...
February 15, 2018: Carbohydrate Polymers
Piyasi Mukhopadhyay, Subhajit Maity, Sudipto Mandal, Abhay Sankar Chakraborti, A K Prajapati, P P Kundu
The study aims for development of an efficient polymeric carrier for evaluating pharmaceutical potentialities in modulating the drug profile of quercetin (QUE) in anti-diabetic research. Alginate and succinyl chitosan are focused in this investigation for encapsulating quercetin into core-shell nanoparticles through ionic cross linking. The FT-IR, XRD, NMR, SEM, TEM, drug entrapment and loading efficiency are commenced to examine the efficacy of the prepared nanoparticles in successful quercetin delivery. Obtained results showed the minimum particle size of ∼91...
February 15, 2018: Carbohydrate Polymers
Mohamed Rehan, Mehrez E El-Naggar, H M Mashaly, Ralph Wilken
The present work addresses an innovative approach for benign development of environmentally synthesis of chitosan-based nanocomposite. The synthesis involves the inclusion via interaction of AgNPs and clay with chitosan (Cs) giving rise to Cs/AgNPs and Cs/AgNPs/clay nanocomposites which when applied independently induce super functionalities. Comparison is made among the two nanocomposites with respect to their intimate association with the in depth cotton fibre-fabric surfaces and the onset of this on the multi-functionalization of cotton fabrics...
February 15, 2018: Carbohydrate Polymers
Mamoni Dash, Sangram K Samal, Andrea Morelli, Cristina Bartoli, Heidi A Declercq, Timothy E L Douglas, Peter Dubruel, Federica Chiellini
Polyelectrolyte complexes (PEC) of chitosan and ulvan were fabricated to study alkaline phosphatase (ALP) mediated formation of apatitic minerals. Scaffolds of the PEC were subjected to ALP and successful mineral formation was studied using SEM, Raman and XRD techniques. Investigation of the morphology via SEM shows globular structures of the deposited minerals, which promoted cell attachment, proliferation and extracellular matrix formation. The PEC and their successful calcium phosphate based mineralization offers a greener route of scaffold fabrication towards developing resorbable materials for tissue engineering...
February 15, 2018: Carbohydrate Polymers
Xinran Xiang, Song Ding, Hongbo Suo, Chao Xu, Zhen Gao, Yi Hu
A nanocomposite (SBA-CIL-CS) which was combined mesoporous silica SBA-15 material with chitosan via ionic liquid as the bridging agent was successfully fabricated. The morphology and structure of the nanocomposite were characterized in detail with transmission electron microscope, fourier transform infrared spectroscopy, thermogravimetric analysis and nitrogen adsorption-desorption techniques. SBA-CIL-CS was investigated as an efficient support for immobilization of porcine pancreas lipase (PPL) and possessed high immobilization efficiency...
February 15, 2018: Carbohydrate Polymers
Shuang Bai, Yong-E Gao, Xiaoqian Ma, Xiaoxiao Shi, Meili Hou, Peng Xue, Yuejun Kang, Zhigang Xu
We report a new reduction-responsive amphiphilic polymeric prodrug based on a linear dextran (DEX) backbone, which was conjugated with an hydrophobic camptothecin (CPT) prodrug block and an hydrophilic poly[poly(ethylene glycol) methyl ether methacrylate] (POEGMA) block [DEX-PCPT-b-POEGMA (DCO)] by atom transfer radical polymerization (ATRP). This amphiphilic prodrug has a unique molecular structure with prominent features, including strong practicability for methacrylate prodrug monomer, high drug loading rate (up to 23wt%), adjustable proportion of hydrophobic and hydrophobic portions, superior stability in aqueous solution, and easy access to cells...
February 15, 2018: Carbohydrate Polymers
Xiaoli Liu, Wenshui Xia, Qixing Jiang, Peipei Yu, Lin Yue
Here, a nontoxic antibacterial material based on Chitosan Oligosaccharide-N-Chlorokojic acid Mannich base (COS-N-MB) that was synthesized by using the selective partial alkylation reaction displaying excellent activity against bacterial infection. The proposed mechanism of the action of COS-N-MB is that this antibacterial material with positive charge and synergistic antibacterial effects can promote it's adsorption to bacterial cell wall through electrostatic interaction and chelating metal cations. It changed the permeability of the membrane, caused cellular leakage, and destroyed the membrane integrity, leading to complete membrane disruption and eventually death of the bacteria...
February 15, 2018: Carbohydrate Polymers
Guangsheng Wu, Chao Feng, Jingjing Quan, Zhongshan Wang, Wei Wei, Shengqi Zang, Shuai Kang, Guangyan Hui, Xiguang Chen, Qintao Wang
Bone regeneration involves complex physiological processes, which is generally regulated and controlled by multiple bioactive molecules. In situ controlled release of combined bioactive factors in a spatiotemporal sequence for adapting the demand of bone regeneration is a desired strategy. In this study, nanoparticle/hydrogel composite system was constructed by incorporating stromal cell derived factor-1α (SDF-1α) and chitosan/tripolyphosphate/hyaluronic acid/antimiRNA-138 nanoparticles (CTH/antimiR-138 NPs) in chitosan/β-sodium glycerol phosphate (CS/GP) hydrogel for rat critical-size calvarial bone regeneration...
February 15, 2018: Carbohydrate Polymers
Chongqing Wang, Hui Wang, Guohua Gu
Alkali treatment of lignocellulosic biomass is conducted to remove hemi-cellulose and lignin, further increasing the reactivity and accessibility of cellulose. Ultrasound-assisted xanthation of alkali cellulose is optimized by response surface methodology (RSM) with a Box-Behnken design. A predicting mathematical model is obtained by fitting experimental data, and it is verified by analysis of variance. Response surface plots and the contour plots obtained from the model are applied to determine the interactions of experimental variables...
February 15, 2018: Carbohydrate Polymers
Shuang Song, Bao Zhang, Sufeng Wu, Lu Huang, Chunqing Ai, Jinfeng Pan, Yi-Cheng Su, Zhongfu Wang, Chengrong Wen
Bone morphogenic protein-2 (BMP-2) is known to promote osteogenesis. To find novel adjuvants to enhance the activity of BMP-2, the present study investigated the structure BMP-2-induced osteogenic activity of a water-soluble polysaccharide from the gonad of pacific abalone (Haliotis discus hannai Ino) named AGSP. Through analysis of aldobiouronic acids released from AGSP, monosaccharide composition comparison of AGSP and its reduced product, and methylation analysis and NMR analysis of AGSP and its desulfated derivative, the main structure residue of AGSP was determined as →3)-GlcA(1→3)-Gal(1→ with sulfated branches comprised of prevelant Gal and minor Glc, and →4)-β-GlcA(1→2)-α-Man(1→ residue was also found...
February 15, 2018: Carbohydrate Polymers
T Priya, N Dhanalakshmi, S Thennarasu, N Thinakaran
Simultaneous determination of Cd2+ and Pb2+ was achieved by using graphene oxide/κ-carrageenan/l-cysteine (GO/κ-Car/l-Cys) nanocomposite modified glassy carbon electrode (GCE) by Square Wave Anodic Stripping Voltammetry (SWASV). The morphology and functionalization of the prepared nanocomposite were characterized by XRD analysis, Raman spectroscopy, Field emission scanning electron microscopy and FTIR analysis. Under optimum conditions, outstanding linearity was obtained for both Cd2+ and Pb2+ in the range from 5 to 50nM with the detection limits as 0...
February 15, 2018: Carbohydrate Polymers
Priya Yadav, Arghya Bandyopadhyay, Anindita Chakraborty, Keka Sarkar
Computational analyses followed by traditional wet-bench experiments have become a method of choice due to successful results. To enhance the solubility and bioavailability of curcumin within chitosan nanoparticle, we have exploited computational methodologies i.e. docking, BBD-RSM and MD simulation for the polymer selection, NPs' formulation, optimization and their stability confirmation in an aqueous medium, respectively. Formulated CSCur NPs were assessed for in-vitro release, which exhibited a sustained release pattern and four-fold higher cytotoxic activity in a nanoparticulated system...
February 15, 2018: Carbohydrate Polymers
Wenqiang Tan, Qing Li, Fang Dong, Jingjing Zhang, Fang Luan, Lijie Wei, Yuan Chen, Zhanyong Guo
In this paper, novel cationic chitosan derivative possessing 1,2,3-triazolium and pyridinium groups was synthesized conveniently via cuprous-catalyzed azide-alkyne cycloaddition (CuAAC) and methylation. FTIR, 1H NMR, and elemental analysis examined the structural characteristics of the synthesized derivatives. The antifungal efficiencies of chitosan derivatives against three plant-threatening fungi were assayed by hypha measurement in vitro. The determination showed that chitosan derivative bearing 1,2,3-triazolium and pyridinium displayed tremendously enhanced antifungal activity as compared with chitosan and chitosan derivative bearing 1,2,3-triazole and pyridine...
February 15, 2018: Carbohydrate Polymers
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