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Carbohydrate Polymers

Xiancai Jiang, Yujun Sun, Hongxiang Zhang, Linxi Hou
In this study, a series of novel quaternized poly(vinyl alcohol)/chitosan/molybdenum disulfide (QPVA/CS/MoS2) anion exchange membranes (AEMs) were prepared for direct methanol alkaline fuel cell (DMAFC). The composite membrane was synthesized by adding different amounts of MoS2 nanosheets (0, 0.1, 0.2, 0.5 and 1wt%) into QPVA/CS mixture solution and using the solution casting method. The crystallinity, thermal and mechanical properties, ion conductivity and resistance to methanol of the QPVA/CS/MoS2 membranes were characterized by X-ray diffraction, thermogravimetric analysis, tensile testing, ion exchange capacity, and methanol permeability measurements, respectively...
January 15, 2018: Carbohydrate Polymers
Farhat Rashid, Sarfraz Hussain, Zaheer Ahmed
Galactomannan, a water-soluble heteropolysaccharide was isolated and purified from seed of fenugreek locally called as Kasuri Methi. Polysaccharide was chemically characterized and its functional attributes were studied in detail. FTIR analysis divulges representative peaks of polysaccharide in region of 3324, 2914 & 1653cm(-1). Galactomannan depicted lower water holding capacity compared to guar gum. Emulsifying activity and emulsion stability of biopolymer was on higher side as compare to reference material...
January 15, 2018: Carbohydrate Polymers
Qian Wang, Xiaoxia Yan, Yanjiao Chang, Lili Ren, Jiang Zhou
Chitin nanofibers were prepared from commercially available chitin powder via esterification modification and subsequent ultrasound treatment. The obtained chitin nanofibers were characterized using dynamic light scattering (DLS), scanning electron microscopy (SEM), Fourier transform infrared (FTIR), (13)C CP-MAS (cross-polarization under magic-angle spinning) solid state nuclear magnetic resonance (NMR), elemental analysis, and X-ray diffraction (XRD). Results showed that the esterification of chitin with maleic anhydride significantly improved the ultrasound disintegration of chitin fibrils into nanofibers...
January 15, 2018: Carbohydrate Polymers
María D Torres, Francisco Chenlo, Ramón Moreira
water adsorption and desorption isotherms of kappa/iota-hybrid carrageenan (KIC) extracted from Mastocarpus stellatus red seaweed as well as commercial kappa-carrageenan (KC) and iota-carrageenan (IC) were obtained at several temperatures (5, 25, 45, 65°C). Spectroscopic and X-ray diffraction techniques allowed identifying the fundamental composition of above biopolymers. Crystallinity values (%) followed the order IC (25.4±0.6)> KIC (9.3±0.4)> KC (4.8±0.2), which nicely matched with the hygroscopic properties of the tested biopolymers (KC > KIC > IC) at each temperature...
January 15, 2018: Carbohydrate Polymers
Yan Wu, Rui Guo, Nannan Cao, Xiangjun Sun, Zhongquan Sui, Qingbin Guo
The rheological properties of polysaccharide (SAP) from Sophora alopecuroides L. seeds were systematically investigated by fitting different models. The steady flow testing indicated that SAP exhibited shear-thinning behaviors, which were enhanced with increasing concentration and decreasing temperature. This was demonstrated quantitatively by Williamson and Arrhenius models. According to the generalized Morris equation, SAP exhibited random coil conformation with the potential to form weak gel-like network...
January 15, 2018: Carbohydrate Polymers
Fernando A Bertoni, Juan C González, Silvia I García, Luis F Sala, Sebastián E Bellú
Water pollution by heavy metals represents a serious problem around the world. Among various treatment techniques for water remediation, adsorption is an effective and versatile method due to the low cost, effectiveness and simplicity. Chitosan is a cationic polysaccharide with an excellent adsorption capacity of heavy metal ions. Chitosan has a high molybdate adsorption capacity (265±1mgg(-1)) at 20°C and pH 2.7. Participation of hydroxyl groups in the adsorption of molybdate anions was confirmed by FT-IR analysis...
January 15, 2018: Carbohydrate Polymers
Benjamin R Riegger, Bernd Bäurer, Aziza Mirzayeva, Günter E M Tovar, Monika Bach
This study investigates the impact of glutaraldehyde (glut) concentration and molecular weight (MW) of six commercially available, highly deacetylated chitosans (Chi) on nanoparticle (Chi-NP) formation by emulsion crosslinking technique and their use as potential adsorber for diclofenac (DCL) and carbamazepine (CBZ). With a glut:primary amine ratio of 1:1 and NaCl as a hydrophile, it was possible to reproducibly synthesize narrowly distributed, spherical Chi-NPs over a broad range of chitosan MW with a high yield...
January 15, 2018: Carbohydrate Polymers
Xi Yang, Benhua Fei, Jianfeng Ma, Xinge Liu, Shumin Yang, Genlin Tian, Zehui Jiang
Herein NaOH/urea aqueous solution was assisted to dissolve bamboo cellulose fibers for the fabrication of porous nanoplatelets wrapped carbon aerogel as an economic and sustainable way in application of supercapacitor. The architecture displayed favorable features, such as a large specific surface area and a great flexibility of 86% at stress of 23kPa. The effects of the KOH activation on the morphology and porous texture of cellulose carbon aerogel were further investigated and correlated with their electrochemical behavior...
January 15, 2018: Carbohydrate Polymers
Sandra A Nascimento, Camila A Rezende
This work is focused in methodologies to obtain cellulose nanocrystals, cellulose nanofibrils, soluble lignin and fermentable sugars from elephant grass, aiming a more integral use of this biomass. To improve hydrolysis, three different pretreatments for biomass delignification and bleaching were compared: 1. Concentrated alkaline peroxide (CP); 2. Diluted alkaline peroxide (DP); and 3. Acid-alkali (AA) pretreatment. Cellulose nanocrystals were obtained from elephant grass leaves by acid hydrolysis, with a 12-16% w/w yield considering the initial biomass weight, and presented high crystallinity index (CI=72-77%) and aspect ratios (30-44), depending on the pretreatment approach...
January 15, 2018: Carbohydrate Polymers
Tanya L Cupino, Billy A Watson, Alan C Cupino, Keiji Oda, Mark G Ghamsary, Salvador Soriano, Wolff M Kirsch
Chitosan polymers (Cs), from which microparticles (CsM) may be precipitated to deliver various intracellular payloads, are generally considered biologically inert. We examined the impact of cell culture conditions on CsM size and the effect of chitosan on CD59 expression in primary human smooth muscle cells. We found that particle concentration and incubation time in biological buffers augmented particle size. Between pH 7.0 and pH 7.5, CsM size increased abruptly. We utilized CsM containing a plasmid with a gene for CD59 (pCsM) to transfect cells...
January 15, 2018: Carbohydrate Polymers
Pankaj K Singh, Anup K Srivastava, Atul Dev, Babita Kaundal, Subhasree Roy Choudhury, Surajit Karmakar
Recurrence of glioblastoma is one of the major concerns due to its heterogeneous nature and association of Glioma Initiating stem-like Cells (GICs). Nanoparticles mediated delivery of chemotherapeutic agent targeting both cancer and glioma stem cells could provide a solution to recurrent malignancies of the glioblastoma tumor. The approach described here provides enhanced chemotherapeutic potency utilizing 1,3β-Glucan as an outer shell to the chitosan nanoparticles (Cs-NPs) loaded with paclitaxel to prevent hemolysis with, the core-shell nano-structure (Cs-PTX-NP) enabling effective chemotherapy against malignant glioblastoma...
January 15, 2018: Carbohydrate Polymers
Zhong Wang, Haijiao Kang, Shujun Zhao, Wei Zhang, Shifeng Zhang, Jianzhang Li
Network-nanostructured cellulose nanofibrils (CNFs) is a promising template onto which to anchor and expand 2D sheets. It is still a huge challenge to regulate the dispersion/interface toward strong yet tough hybrid materials. This paper reports a novel design for interface anchoring GO nanosheets with TEMPO-oxidized CNFs (TA@rGO-CNFs) that is induced by the self-polymerization of catecholamine-based tannic acid (TA). The high-functionality TA@rGO-CNFs nanohybrids were investigated as both physical and chemical cross-linkers to the natural plant-derived soy protein isolate (SPI) based films, which facilitate multiple interfacial adhesion and a covalent network between the SPI matrix and TA@rGO-CNFs nanosheets bearing poly (tannic acid) (PTA) adhesion layers...
January 15, 2018: Carbohydrate Polymers
Samuel H Clasen, Carmen M O Müller, Alexandre L Parize, Alfredo T N Pires
Cassava starch was grafted with three different esters by the etherification reaction and its modification was characterized by (1)H NMR, FTIR, DSC, SEM, XDR, contact angle and SLS. The samples grafted with diethyl maleate, dipropyl maleate, and dibutyl maleate showed DS values of 2.3, 1.0 and 2.0, respectively, determined from (1)H NMR analysis and confirmed by FTIR analysis, with the appearance of bands at 1721, 1550 and 1126cm(-1). The FTIR, XRD, SEM and DSC results indicated a change in the intra and intermolecular hydrogen interactions in the grafted starch when compared to native starch...
January 15, 2018: Carbohydrate Polymers
Akbar Ali, Showkat Ali Ganie, Nasreen Mazumdar
Gum arabic, a plant polysaccharide was oxidized with periodate to produce aldehyde groups by the cleavage of diols present in the sugar units. The oxidized gum was then iodinated with iodine monochloride (ICl) and the interaction between electrophilic iodine, I(+) and reactive carbonyl groups of the modified gum was studied.Results of titrimetric estimation performed to determine the extent of oxidation and aldehyde content in the oxidized gum showed that degree of oxidation ranged between 19.68-50.19% which was observed to increase with periodate concentration; the corresponding aldehyde content was calculated to be 5...
January 15, 2018: Carbohydrate Polymers
Kamalesh Prasad, Dibyendu Mondal, Mukesh Sharma, Mara G Freire, Chandrakant Mukesh, Jitkumar Bhatt
Ion gels and self-healing gels prepared using ionic liquids (ILs) and deep eutectic solvents (DESs) have been largely investigated in the past years due to their remarkable applications in different research areas. Herewith we provide an overview on the ILs and DESs used for the preparation of ion gels, highlight the preparation and physicochemical characteristics of stimuli responsive gel materials based on co-polymers and biopolymers, with special emphasis on polysaccharides and discuss their applications...
January 15, 2018: Carbohydrate Polymers
Juanjuan Guo, Zhichang Zheng, Xu Lu, Shaoxiao Zeng, Chi Chen, Longtao Zhang, Baodong Zheng
κ-Carrageenan oligosaccharides (KCOs) are promising agents for treating inflammatory diseases. However, the lack of purification and structural elucidation of KCOs has limited structure-function evaluation. In this study, using a system coupling medium pressure liquid chromatography (MPLC) with an evaporative light scattering detector (ELSD), four types of KCOs were separated. The total yield of the four KCO powders was ∼5.02% after purification (KCOs/κ-carrageenan, w/w). Their structural identities were characterised by ESI-MS, CID-MS/MS and NMR, as κ-neocarrabiose (α-DA-1,3-G4Srα/β), κ-neocarratetraose (α-DA-1,3-β-G4S-1,4-α-DA-1,3-G4Srα/β), κ-neocarrahexaose (α-DA-1,3-β-G4S-1,4-α-DA-1,3-β-G4S-1,4-α-DA-1,3-G4Srα/β) and heterozygous κ/ι-neocarrahexaose (α-DA/DA2S-1,3-β-G4S-1,4-α-DA-1,3-β-G4S-1,4-α-DA-1,3-G4Srα/β)...
January 15, 2018: Carbohydrate Polymers
Huanling Wu, Gareth R Williams, Junzi Wu, Jianrong Wu, Shiwei Niu, Heyu Li, Haijun Wang, Limin Zhu
The objective of this work was to prepare a novel filament with good biocompatibility and mechanical performance which can meet the demands of surgical sutures. Bacterial cellulose nanocrystals (BCNCs) were used to reinforce regenerated chitin (RC) fibers to form BCNC/RC filaments. Mechanical performance measurements demonstrated that the strength of the BCNC/RC filament was increased dramatically over the RC analogue. A yarn made of 30 BCNC-loaded fibers also achieved satisfactory mechanical performance, with a knot-pull tensile strength of 9...
January 15, 2018: Carbohydrate Polymers
Suyong Kim, Jeongwon Lee, F Lahiji Shayan, Seohyun Kim, Inyoung Huh, Yonghao Ma, Huisuk Yang, Geonwoo Kang, Hyungil Jung
A dissolving microneedle (DMN) patch encapsulated with ascorbic acid 2-glucoside (AA2G) in a needle-shaped hyaluronic acid (HA) backbone was fabricated and sterilized by electron beam (e-beam, 5-40kGy) and gamma ray (γ-ray, 5-30kGy). DMN structures maintained their morphologies and fracture force regardless of e-beam and γ-ray irradiation doses. Both e-beam (40kGy) and γ-ray (20 and 30kGy) met the product sterility requirements for cosmetics and vaccines; however, γ-ray irradiation significantly degraded the encapsulated AA2G, while e-beam maintained AA2G activity...
January 15, 2018: Carbohydrate Polymers
Ying Xie, Yuan Yao
Effective solubilizers for poorly water-soluble active pharmaceutical ingredients (APIs) are highly desirable. This study introduced an amphiphilic dendrimer-like biopolymer, octenylsuccinate hydroxypropyl phytoglycogen (OHPP) as a new solubilizer. The molar substitution degree of octenylsuccinate and hydroxypropyl groups of OHPP was 0.51 and 1.69, respectively. The weight-average molecular weight, Z-average root mean square radius, and Zeta-potential of OHPP were 1.507×10(7)g/mol, 22.6nm, and -23.6mV, respectively...
January 15, 2018: Carbohydrate Polymers
Yi-Hsuan Tsai, Yu-Ning Yang, Yi-Cheng Ho, Min-Lang Tsai, Fwu-Long Mi
Bacterial cellulose (BC) is a biopolymer composed of nanofibers which has excellent film-forming ability. However, BC do not have antibacterial or antioxidant activity, thus limiting the applicability of BC for food and biomedical applications. In this study, flavonoid silymarin (SMN) and zein were assembled into spherical SMN-Zein nanoparticles that could be effectively adsorbed onto BC nanofibers. SMN-Zein nanoparticles greatly changed the wettability and swelling property of BC films due to the formation of nanoparticles/nanofibers nanocomposites...
January 15, 2018: Carbohydrate Polymers
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