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Carbohydrate Polymers

Yunhui Xu, Dingding Chen, Zhaofang Du, Jifeng Li, Yunxia Wang, Zhen Yang, Fengxia Peng
A novel eco-friendly production of silk fibroin-grafted carboxylic cotton fabrics without using any crosslinking agents was developed via the reaction of silk fibroin with oxidized cotton. The effect of reaction parameters on mechanical properties of oxidized fabrics and graft add-on of silk fibroin in grafted fabrics was examined. The results showed that appropriate oxidation time of HNO3/H3PO4-NaNO2 mixture and grafting time of fibroin were 45min and 2h respectively. FTIR analysis of grafted sample indicated that the CN amido bond was generated through the reaction between primary amines in silk fibroin and carboxyl groups in oxidized cotton, which was further confirmed by XPS spectra...
April 1, 2017: Carbohydrate Polymers
Usman Ali, Vandana Bijalwan, Santanu Basu, Atul Kumar Kesarwani, Koushik Mazumder
Arabinoxylans (AX) was isolated from wheat straw, whereas β-glucan (BG) was extracted from oat flour. The compositional analysis indicated wheat straw AX contained arabinose and xylose as major constituent sugars whereas higher β-glucan content (77%) was found in the extracted material from oat flour. The BG was conjugated with lauric (LA), myristic (MA), palmitic (PA), stearic (SA) and oleic (OA) acid to prepare corresponding β-glucan-fatty acid esters (BGFAs) with nearly similar degree of substitution...
April 1, 2017: Carbohydrate Polymers
Katja Heise, Christine Rossberg, Juliane Strätz, Christian Bäurich, Erica Brendler, Harald Keller, Steffen Fischer
In this issue, different chemical (alkaline and sulfite pulping, ozonolysis) and mechanical (vibratory ball milling) pre-treatments were utilized for activating wheat straw and beech sawdust prior to carboxymethylation. Detailed analysis by a range of methods, including Klason-lignin, cellulose and hemicellulose quantification, Powder-X-ray diffraction (PXRD) and attenuated total reflection (ATR) IR spectroscopy, enabled the investigation of material alterations. Subsequently, carboxymethylation was carried out with both untreated and activated materials, allowing the evaluation of activation steps by determining degrees of substitution with carboxymethyl groups (DSCM)...
April 1, 2017: Carbohydrate Polymers
Mehmet Cabuk, Yusuf Alan, H Ibrahim Unal
In this study, chitosan (CS), Na(+)-bentonite (Na(+)-BNT) and chitosan/organo-bentonite (CS/O-BNT) biodegradable composites having three different compositions were investigated. Electrokinetic measurements were examined in aqueous medium by taking the effects pH, electrolytes (NaCl and BaCl2), surfactants (CTAB and SDS), and temperature into account. It was noticed that the initial ζ-potential of Na(+)-BNT shifted from negative (ζ=-35mV) to positive region (ζ=+13mV) with increasing polycationic CS content in the composite structure as aimed...
April 1, 2017: Carbohydrate Polymers
Mar Collado-González, Mercedes G Montalbán, Jorge Peña-García, Horacio Pérez-Sánchez, Gloria Víllora, F Guillermo Díaz Baños
Chitosan is a biocompatible polysaccharide with positive Z potential which can stabilize negative charged nanoparticles. Silk fibroin nanoparticles and citrate gold nanoparticles, both with negative Z potential, but they form aggregates at physiological ionic strength. In this work, we study the behavior of chitosan in solution when the ionic strength of the medium is increased and how the concentration of chitosan and the proportion of the two components (chitosan and AuNP or SFN) significantly affect the stability and size of the nanocomposites formed...
April 1, 2017: Carbohydrate Polymers
Qingwen Xu, Huihua Liu, Zi Ye, Kaihui Nan, Sen Lin, Hao Chen, Bailiang Wang
The adhesion of bacteria and subsequent formation of biofilm on the surface of implants greatly affect the long-term use of the implants. The low molar mass gentamicin (GS) cations could hardly be directly incorporated into the multilayer films through alternately deposition with a polyanion. Herein, we have designed and constructed a (poly(acrylic acid)/(polyvinylpyrrolidone/chitosan))n ((PAA/(PVP/CHI))n) multilayer films through layer-by-layer self-assembly method. Through increasing the pH to destroy hydrogen bonding between PAA and PVP, PVP released into the solution and GS simultaneously combined with PAA through electrostatic interactions...
April 1, 2017: Carbohydrate Polymers
Qian Li, Wei Wang, Yun Zhu, Yao Chen, Weijie Zhang, Ping Yu, Guanghua Mao, Ting Zhao, Weiwei Feng, Liuqing Yang, Xiangyang Wu
Se-GFP-22, a heteropolysaccharide, with a weight-average Mw of 4.13×10(6)Da, was purified from the crude Se-polysaccharide (Se-GFP) isolated from fruit bodies of Se-enriched Grifola frondosa. Selenium was accumulated efficiently in Grifola frondosa during cultivation with Na2SeO3. The structure was investigated through FT-IR, GC, GC-MS, NMR, HPSEC-MALL-RI, particle size, Conge-red test, CD, AFM and SEM. Se-GFP-22 was deduced as a backbone chain of 1,4-α-d-Glcp units with a branched point at C6 of both 1,3,6-β-d-Manp and 1,4,6-α-d-Galp units...
April 1, 2017: Carbohydrate Polymers
Di Li, Jiandong Han, Jianxun Ding, Li Chen, Xuesi Chen
The acid-sensitive polymer prodrugs have attracted increasing attention because of their selective intratumoral or intracellular drug release. Herein, two intracellular acid-sensitive dextran-doxorubicin (Dex-DOX) conjugates with similar drug binding rate were synthesized through the Schiff base reaction between the aldehyde group in the oxidized Dex with different lengths and the amino group of DOX. The amphiphilic Dex-DOX conjugates self-assembled into micellar nanoparticles in phosphate-buffered saline (PBS)...
April 1, 2017: Carbohydrate Polymers
Isala Dueramae, Masaru Yoneyama, Naoki Shinyashiki, Shin Yagihara, Rio Kita
No abstract text is available yet for this article.
April 1, 2017: Carbohydrate Polymers
Ine Van Nieuwenhove, Achim Salamon, Stefanie Adam, Peter Dubruel, Sandra Van Vlierberghe, Kirsten Peters
Tissue regeneration often occurs only to a limited extent. By providing a three-dimensional matrix serving as a surrogate extracellular matrix that promotes adult stem cell adhesion, proliferation and differentiation, scaffold-guided tissue regeneration aims at overcoming this limitation. In this study, we applied hydrogels made from crosslinkable gelatin, the hydrolyzed form of collagen, and functionalized starch which were characterized in depth and optimized as described in Van Nieuwenhove et al., 2016. "Gelatin- and Starch-Based Hydrogels...
April 1, 2017: Carbohydrate Polymers
Xiaoyan Tan, Xiaoxi Li, Ling Chen, Fengwei Xie, Lin Li, Jidong Huang
Breadfruit starch was subjected to heat-moisture treatment (HMT) at different moisture content (MC). HMT did not apparently change the starch granule morphology but decreased the molecular weight and increased the amylose content. With increased MC, HMT transformed the crystalline structure (B→A+B→A) and decreased the relative crystallinity. With ≥25% MC, the scattering peak at ca. 0.6nm(-1) disappeared, suggesting the lamellar structure was damaged. Compared with native starch, HMT-modified samples showed greater thermostability...
April 1, 2017: Carbohydrate Polymers
Tomáš Bobula, Radovan Buffa, Martina Hermannová, Lenka Kohutová, Pavlína Procházková, Hana Vágnerová, Martin Čepa, Lucie Wolfová, Ondřej Židek, Vladimír Velebný
A new photopolymerizable derivative of hyaluronan (methacrylhydrazide-HA, MAHA) was prepared by carbodiimide chemistry. The reaction conditions were optimized for molecular weight (Mw), reaction time and amount of reagents with a degree of methacrylation (DM) ranging from 2% to 58%. Methacrylhydrazide-HA was hydrolytically stable (PBS, 7days, 37°C) in contrast to commonly used methacrylester analoque (23% hydrolyzed). MAHA readily photopolymerized into densely crosslinked hydrogels under physiological conditions...
April 1, 2017: Carbohydrate Polymers
Zhuorong Li, Jiao Meng, Wei Wang, Zongyuan Wang, Minyue Li, Tao Chen, Chang-Jun Liu
Functionalization of cotton by fabricating Ag nanoparticles (NPs) on cotton surface has aroused great interest for its promising applications for chemical, electronic, photonic and many other devices. Herein, a simple and rapid room temperature electron reduction, which uses argon glow discharge as the electron source, was employed to fabricate Ag NPs on cotton without using any chemical reducing agent. The color of Ag NP loaded cotton changes from light yellow to black upon the increasing Ag loading amount, while the average size of Ag NPs on the cotton barely changes from 4...
April 1, 2017: Carbohydrate Polymers
Minghua Lai, Jingnan Wang, Jiayun Tan, Jiahao Luo, Li-Ming Zhang, David Y B Deng, Liqun Yang
To improve the small intestinal absorption efficacy of Astragalus polysaccharides (APS) through oral administration, amphiphilic chitosan derivatives conjugated with deoxycholic acid residues in the absence and presence of vitamin B12 residues (DA-Chit and VB12-DA-Chit, respectively) were synthesized and characterized by FTIR and NMR spectroscopy. APS and the amphiphilic chitosan derivatives formed the nano-complexes with positive zeta potentials in the size of 100-150nm observed using scanning electron microscopy...
April 1, 2017: Carbohydrate Polymers
Ya-Ru Dong, Shu-Jie Cheng, Guo-Hong Qi, Zhi-Ping Yang, Shi-Yu Yin, Gui-Tang Chen
FVP is polysacchrides obtained from Flammulina velutipes. A polysacchride named FVP2 was isolated from FVP by DEAE cellulose-52 chromatography and Sephadex G-100 size-exclusion chromatography. FVP-Fe and FVP2-Fe were synthesized by neutralization of FeCl3 carbohydrate solution. The antibacterial and antifungal activities of FVP, FVP2, FVP-Fe, FVP2-Fe were investigated and their antioxidant effects on hydroxyl, 2,2-diphenyl-1-picrylhydrazyl (DPPH), superoxide anion, 2,2'-azobis-(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) radicals, reducing power, inhibition of malondialdehyde (MDA) were assessed in vitro...
April 1, 2017: Carbohydrate Polymers
Xin Feng, Yafei Zhao, Yaoquan Jiang, Miao Miao, Shaomei Cao, Jianhui Fang
High-efficient transparent UV-blocking nanocellulose (NC) films were successfully assembled by pressured-extrusion of the composites of carbon dots (CDs), 2,2,6,6-tetramethyl-1-piperidinyloxy (TEMPO) radical mediated oxidized nanocellulose (ONC) and ZnO nanostructures. ONC nanofibrils were firstly extracted from bamboo fibers and subsequently prepared by applying TEMPO oxidation. The as-obtained CDs-ONC-ZnO films exhibited high visible light transparency, excellent thermal stability and enhanced UV-blocking properties...
April 1, 2017: Carbohydrate Polymers
Muhammad Asgher, Zanib Ahmad, Hafiz M N Iqbal
In the present study, in-house extracted ligninolytic consortium was used as a green catalyst to modify the pristine wheat straw through de-lignification. The ligninolytic consortium showed an enhanced level of de-lignification with a maximal cellulose exposure from 24% to 76.54% cellulose. The de-lignified wheat straw was further strengthened using bacterial cellulose integration. Subsequently, a well-known compression molding technique was used to develop bio-composites from a de-lignified and bacterially modified wheat straw in the presence of polyvinyl alcohol (PVA) and glycerol as a plasticizer...
April 1, 2017: Carbohydrate Polymers
Qiyang Wang, Jinhua Guo, Yixiang Wang, Lingyun Chen, Jie Cai, Lina Zhang
In this study cellulose hydrogels with lanthanide ions nanoparticles embedded in were prepared via in situ doping using a low-temperature alkali hydroxide/urea aqueous solution as a cellulose solvent. Depending on the type and relative concentrations of the constituent lanthanide ions, the color of light emission were modulated to generate the three primary colors and other adjusted colors by blending red, green and blue at certain ratios. This work has opened new and convenient pathway to create regulated fluorescent cellulose hydrogels for potential applications in the fields of bioimaging and fluoroimmunoassay...
April 1, 2017: Carbohydrate Polymers
Seref Akay, Rene Heils, Hoc Khiem Trieu, Irina Smirnova, Ozlem Yesil-Celiktas
The objective of this study was to develop an injectable alginate based formulation for immobilizing enzymes into microfluidic systems. The gelation was induced upon lowering the pH by addition of d-glucono-δ-lactone (GDL) and release of Ca(+) ions from solid CaCO3. The effects of GDL concentration on enzymatic activity and gelation time were investigated. The results indicated that increasing the GDL concentration increased both surface area and enzymatic activity. Also, chitosan was added to the formulation at different ratios to enhance the stability of enzyme during immobilization...
April 1, 2017: Carbohydrate Polymers
Nesrine Riahi, Benoît Liberelle, Olivier Henry, Gregory De Crescenzo
Dextran is one of the hydrophilic polymers that is used for hydrogel preparation. As any polysaccharide, it presents a high density of hydroxyl groups, which make possible several types of derivatization and crosslinking reactions. Furthermore, dextran is an excellent candidate for hydrogel fabrication with controlled cell/scaffold interactions as it is resistant to protein adsorption and cell adhesion. RGD peptide can be grafted to the dextran in order to promote selected cell adhesion and proliferation. Altogether, we have developed a novel strategy to graft the RGD peptide sequence to dextran-based hydrogel using divinyl sulfone as a linker...
April 1, 2017: Carbohydrate Polymers
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