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  • Impact of TEMPO-Oxidization Strength on the Properties of Cellulose Nanofibril Reinforced Polyvinyl Acetate Nanocomposites
    Carbohydr. Polym. (IF 4.811) Pub Date : 2017-11-21
    Karima Ben Hamou, Hamid Kaddami, Alain Dufresne, Sami Boufi, Albert Magnin, Fouad Erchiqui

    Nanocomposites of polyvinyl acetate (PVAc) reinforced with two different TEMPO-oxidized cellulose nanofibrils (CNF) were prepared by casting/evaporation method. These two sets of CNF, designed as CNF-O–5 min (5 min of oxidation) and CNF-O–120 min (120 min of oxidation), are different by their surface charge, geometrical characteristics and crystallinity index. The weight fraction of CNF was changed from 1 to 10 wt%. The mechanical and thermal properties of the nanocomposite films were studied by dynamic mechanical thermal analysis (DMTA), differential scanning calorimetry (DSC), thermogravimetric analysis (TGA) and tensile tests, and their morphology was investigated by scanning electron microscopy (SEM). For all nanocomposites, increasing amounts of CNF led to a significant increase in the mechanical properties (increase in Young’s modulus and tensile strength) and in the water uptake. On the other hand, the lost of transparency became very significant when the weight fraction of CNF exceeded 3 wt%. The comparison between the two sets of CNF showed that PVAc/CNF-O–5 min nanocomposite films had a tendency to display higher tensile strength and elastic modulus than those of PVAc/CNF-O–120 min films. In addition, the water uptake is higher for PVAc/CNF-O–120 min. Finally, the thermal stability analyses for PVAc/CNF films show that shorter and more charged fibrils (CNF-O–120 min) appear to slightly increase the thermal stability compared to other larger and less charged fibrils (CNF-O–5 min). All these results are discussed in connection with the CNFs characteristics.

    更新日期:2017-11-21
  • Montmorillonite@chitosan-poly (ethylene oxide) nanofibrous membrane enhancing poly (vinyl alcohol-co-ethylene) composite film
    Carbohydr. Polym. (IF 4.811) Pub Date : 2017-11-21
    Peng Wang, Hualin Wang, Jingrong Liu, Pengfei Wang, Suwei Jiang, Xingjiang Li, Shaotong Jiang

    A montmorillonite@chitosan-poly (ethylene oxide) nanofibrous membrane (MMT@CPF) enhancing poly (vinyl alcohol-co-ethylene) (EVOH-MMT@CPF) composite film was developed by using a space-filling embedding method. The structure of EVOH-MMT@CPF was characterized, and the thermal stability, mechanical and barrier properties of the films were investigated. The CPF was fabricated via electrospinning technique and the self-assembly of MMT nano-platelets on CPF was achieved by the driving of electrostatic interactions between MMT nano-platelet and CPF. The experimental results indicated that the well-kept MMT@CPF after embedding in the EVOH matrix significantly improved the thermal stability and mechanical properties of the film, and also endowed the film with outstanding oxygen barrier (0.2 × 10−16 cm3 cm cm−2 s−1 Pa−1) and good moisture barrier (4.6 × 10−6 g m m−2 s−1 atm−1 under a relative humidity of 90%) by prolonging the tortuous paths for molecule penetration. The composite film may have a great potential application in food packaging.

    更新日期:2017-11-21
  • A closer look to cell structural barriers affecting starch digestibility in beans
    Carbohydr. Polym. (IF 4.811) Pub Date : 2017-11-20
    Ana M. Rovalino-Córdova, Vincenzo Fogliano, Edoardo Capuano

    Isolated bean cells were used to understand the contribution of cell wall and cytoplasmic matrix on starch digestibility. Cotyledon cells were treated enzymatically and mechanically to reduce the level of cell intactness. SEM and chemical characterization revealed that enzymatic treatment modified cell wall thickness and porosity without altering the cytoplasmic matrix, whereas mechanical treatment completely disrupted cell structure. Decreasing cell intactness increased the rate but not the extent of starch digestion in-vitro. It was concluded that cell wall serves as a permeable barrier limiting the access of digestive enzymes. Cytoplasmic matrix, on the other hand, reduced further the accessibility of amylase to starch affecting its hydrolysis rate. In addition, it was proven that cell structural changes, if any, occurring during digestion had no effect on starch hydrolysis.

    更新日期:2017-11-20
  • Microwave assisted hydrothermal extraction of polysaccharides from Ulva prolifera: functional properties and bioactivities
    Carbohydr. Polym. (IF 4.811) Pub Date : 2017-11-20
    Yuan Yuan, Xiang Xu, Changliang Jing, Ping Zou, Chengsheng Zhang, Yiqiang Li

    Sulfated polysaccharides from green tide algae Ulva prolifera were effectively extracted by microwave assisted hydrothermal extraction technology. The properties and bioactivities of polysaccharides could be controlled by extraction conditions. While rhamnose, galacturonic acid and glucose were major monosaccharides at 90 °C with 0.01 M HCl, glucose was the major monomer at 150 °C with 0.1 M HCl. Sulfur content increased with temperature and acid concentration, while molecular weight decreased with temperature and concentration. Functional property analysis showed that polysaccharides extracted from 90 °C, 0.05 M HCl had the best water-holding capacity (41.32 g/g) and oil-holding capacity (15.09 g/g), and polysaccharides extracted from 150 °C, 0.05 M HCl had the best foaming properties (foaming capacity 143% and foaming stability 113%, respectively). In addition, polysaccharides extracted from 150 °C, 0.1 M HCl exhibited higher antioxidant activity and pancreatic lipase inhibition activity. The relationship between polysaccharide compositions/molecular weight and properties/bioactivities was discussed.

    更新日期:2017-11-20
  • Synthesis of Carbohydrate Conjugated 6A,6D-Bifunctionalized β Cyclodextrin Derivatives as Potential Liver Cancer Drug Carriers
    Carbohydr. Polym. (IF 4.811) Pub Date : 2017-11-20
    Yili Ding, Chamakura V.N.S. Vara Prasad, Charles Ding, Bingyun Wang

    Galactosyl and lactosyl conjugated 6A,6D-bifunctionlized β cyclodextrin derivatives were designed and synthesized as the potential liver cancer drug carriers through SN2 replacement and click reactions in order to increase liver cancer drug’s targeting ability, solubility and stability. The synthetic methods and strategies to obtain the designed compounds were discussed.

    更新日期:2017-11-20
  • Use of heparinized bacterial cellulose based scaffold for improving angiogenesis in tissue regeneration
    Carbohydr. Polym. (IF 4.811) Pub Date : 2017-11-17
    Baoxiu Wang, Xiangguo Lv, Shiyan Chen, Zhe Li, Jingjing Yao, Xufeng Peng, Chao Feng, Yuemin Xu, Huaping Wang

    Vascularization is a prerequisite to achieve tissue regeneration especially for long-term survival of a scaffold. During the regeneration process, the delivery of angiogenic factors is very important for developing a vascular network. In this paper, vascular endothelial growth factor (VEGF)-loaded 3D porous bacterial cellulose/gelatin (B/G) scaffolds modified with heparin were firstly prepared. The pro-angiogenic effects of scaffolds towards proliferation and migration of endothelial cells (PIECs) were evaluated as well as in vivo implantation. Results showed that the B/G scaffold modified with heparin could provide a prolonged release of VEGF for two weeks. In vitro cellular assays showed that proliferation and migration were promoted in the presence of VEGF. Subcutaneous implantation demonstrated that angiogenesis was significantly improved for the heparinized scaffolds loaded with VEGF (V-B/G/H), compared to B/G scaffold. The resulting scaffold with sustained delivery of VEGF could be potential and effective tissue engineered candidates in tissue regeneration for future clinical applications.

    更新日期:2017-11-20
  • Exploring the mechanism of high degree of delignification inhibits cellulose conversion efficiency
    Carbohydr. Polym. (IF 4.811) Pub Date : 2017-11-17
    Dayong Ding, Xia Zhou, Tingting You, Xun Zhang, Xueming Zhang, Feng Xu

    This study explored the mechanism that high degree of delignification (DD) inhibits enzymatic hydrolysis. Sample with DD of 86.22% achieved the highest cellulose conversion of 68.26%, and the cell wall exhibited defibrillation of macrofibrils and erosion of microfibrils during enzymatic hydrolysis. Cracks between microfibrils are formed within the cell wall, getting the largest specific surface area, which greatly enhanced cellulose conversion. However, high DD of 96.58% resulted in dramatic reduction of cellulose conversion to 56.60% which was evidenced to be the synergistic effect of internal cell wall collapse and microfibrils reaggregation. These ultrastructural changes dominated upon this condition and induced a more compact surface structure which significantly hinders the accessibility of cellulase. The CrI value increased after delignification but changed little with the increased DD, suggesting limited influence of DD on crystalline structure. The results indicate that certain amount of lignin retained may be essential to enhance cellulose conversion.

    更新日期:2017-11-20
  • Monitoring succinoglycan production in single Sinorhizobium meliloti cells by Calcofluor white M2R staining and time-lapse microscopy
    Carbohydr. Polym. (IF 4.811) Pub Date : 2017-11-16
    Edgardo Jofré, Juan Pablo Liaudat, Daniela Medeot, Anke Becker

    Here, we describe a simple, non-time consuming and inexpensive method for monitoring of Calcofluor white M2R-binding exopolysaccharides in individual bacterial cells. This method was demonstrated by time-lapse microscopy of succinoglycan-producing cells of the plant-symbiotic alpha-proteobacterium Sinorhizobium meliloti. The method is most likely applicable to other bacteria producing β-(1 → 3) and β-(1 → 4) linked polysaccharides.

    更新日期:2017-11-20
  • Thiolated citrus low-methoxyl pectin: Synthesis, characterization and rheological and oxidation-responsive gelling properties
    Carbohydr. Polym. (IF 4.811) Pub Date : 2017-11-16
    Jinfeng Chen, Fayin Ye, Yun Zhou, Guohua Zhao

    In the present study, citrus low-methoxyl pectin was modified by conjugating cysteine via amide bonds, and the resultant polymer (CYS-PEC) was characterized. CYS-PEC conjugates with thiol contents varying from 77.8 μmol/g to 296 μmol/g were synthesized, and the successful conjugation was evidenced by elemental, and FT-IR analyses. The sulfur in CYS-PEC is predominately in the thiol form, with a minor fraction forming disulfide bonds (∼15%), which occur when thiol/disulfide interchange interrupts the intended thiolation. Both native and modified pectin dispersions exhibited strong pseudoplastic properties, and the frequency sweeps revealed them to be dispersions containing microgel particles. Dynamic viscoelastic analysis was used to determine the oxidation-response gelling capacities of polymer dispersions containing H2O2, especially those that are highly thiolated and have cross-linked gel properties. For oxidation-induced CYS-PEC gels, their gelation time, hardness, viscosity and elastic moduli and swelling–disintegration ratio are dependent on the thiol group content, H2O2 concentration and polymer concentration.

    更新日期:2017-11-20
  • Anti-proliferative activity of a purified polysaccharide isolated from the basidiomycete fungus Paxillus involutus
    Carbohydr. Polym. (IF 4.811) Pub Date : 2017-11-16
    Ankush Barad, Sebastian Mackedenski, Wai Ming Li, Xiao Jie Li, Bryan Chu Chwen Lim, Faran Rashid, Linda E. Tackaberry, Hugues B. Massicotte, Keith N. Egger, Kerry Reimer, Peter C.K. Cheung, Chow H. Lee

    A growth-inhibitory polysaccharide (GIPinv) was purified using size-exclusion and ion-exchange chromatography from the fourth sodium hydroxide extraction step of a fungus found in British Columbia. The fungus was genetically identified as a member of the Paxillus involutus complex. GIPinv has an average molecular weight of 229 kDa and is a heteroglycan composed of glucose (65.9%), galactose (20.8%), mannose (7.8%), fucose (3.2%) and xylose (2.3%). GC–MS methylation analysis suggests that GIPinv has mixed linkages in the backbone containing (1 → 6)-Gal (25.5%), (1 → 4)-Glc (18.3%), (1 → 6)-Glc (8.3%), (1 → 3)-Glc (5.3%) and (1 → 2)-Xyl (4.5%). GIPinv has branching points at (1 → 2, 6)-Man (8.6%) and (1 → 3, 6)-Man (4.9%) having unsubstituted fucose (8.3%) and glucose (16.3%) as terminal sugars. GIPinv had growth-inhibitory activity against several cancer cell lines and triggered apoptosis. GIPinv should be further explored as a potential anti-cancer agent and a unique polysaccharide.

    更新日期:2017-11-20
  • Optimization of enzymatic production of prebiotic galacto/galacto(arabino)-oligosaccharides and oligomers from potato rhamnogalacturonan I
    Carbohydr. Polym. (IF 4.811) Pub Date : 2017-11-02
    Nastaran Khodaei, Salwa Karboune

    A bi-enzymatic system using two multi-enzymatic preparations (Depol 670 L and Gamanase 1.5 L) was investigated for the production of prebiotic galacto/galacto(arabino)-oligosaccharides and oligomers with well-defined degree of polymerisation (DP) from potato galactan-rich rhamnogalacturonan I. Depending on the reaction condition, yields of low (DP of 2–6) and high-MW oligosaccharides (DP of 7–12) and oligomers (DP of 13–70) varied between 0.1–13.9, 0.0–37.5 and 0.0–75.7%, respectively. Substrate concentration and Depol 670 L/Gamanase 1.5 L ratio were identified as the most significant linear terms in oligosaccharide and oligomer yield models, respectively. Moreover, interaction between reaction time and substrate concentration had a significant effect on the yield of oligosaccharides, while interaction between reaction time and Depol 670 L/Gamanase 1.5 L ratio affected significantly the yield of oligomers. Higher yields of both oligosaccharides and oligomers were obtained when equal amount of Depol 670L and Gamanase 1.5 L was used in combination. The DP and the monosaccharide composition of the generated galacto/galacto(arabino)-oligosaccharides and oligomers were confirmed.

    更新日期:2017-11-20
  • HPMC granules by wet granulation process: Effect of vitamin load on physicochemical, mechanical and release properties
    Carbohydr. Polym. (IF 4.811) Pub Date : 2017-11-16
    Veronica De Simone, Annalisa Dalmoro, Gaetano Lamberti, Diego Caccavo, Matteo d’Amore, Anna Angela Barba

    Due to its versatile properties, hydroxypropyl methylcellulose (HPMC) is largely used in many applications and deeply studied in the various fields such as pharmaceuticals, biomaterials, agriculture, food, water purification. In this work, vitamin B12 loaded HPMC granules were produced to investigate their potential application as nutraceutical products. To this aim the impact of vitamin load on physico-chemical, mechanical and release properties of granules, achieved by wet granulation process, was investigated. In particular, three different loads of B12 (1%, 2.3% and 5% w/w) were assayed. Unloaded granules (used as control) and loaded granules were dried, sieved, and then the suitable fraction for practical uses, 0.45–2 mm in size, was fully characterized. Results showed that the vitamin incorporation of 5% reduced the granulation performance in the range size of 0.45–2 mm and led granules with higher porosity, more rigid and less elastic structures compared to unloaded granules and those loaded at 1% and 2.3% of B12. Vitamin release kinetics of fresh and aged granules were roughly found the same trends for all the prepared lots; however, the vitamin B12 was released more slowly when added with a load at 1% w/w, suggesting a better incorporation.

    更新日期:2017-11-20
  • Immunostimulatory and anti-metastatic activity of polysaccharides isolated from byproducts of the corn starch industry
    Carbohydr. Polym. (IF 4.811) Pub Date : 2017-11-16
    Sue Jung Lee, Ho Sung Lee, Sun Young Kim, Kwang-Soon Shin

    Corn steep liquor (CSL) is a major by-product of the corn steeping process that is utilized in the wet milling industry. To develop new physiologically active polysaccharides from CSL, polysaccharides were isolated and their innate immunostimulatory and anti-metastatic activities were investigated. Corn byproduct polysaccharides (CBP) were preferentially isolated from CSL and further separated into supernatant (CBP1S) and precipitate (CBP1P) fractions. The anti-complementary activity of CBP1S was more potent than CBP1P and CBP. In addition, CBP1S enhanced production of macrophage-stimulating cytokines (e.g., IL-6 and IL-12) and natural killer (NK) cell-activating substances (e.g., granzyme and interferon-γ). Further, CBP1S significantly inhibited lung metastasis at a dose of 1000 μg per mouse in an experimental lung metastasis model. These results suggest that CBP1S seems to promote the inhibition of lung metastasis through a mechanism leading to stimulation of the innate immune system, and CBP1S could be used as immunostimulating agents and for industrial applications.

    更新日期:2017-11-20
  • A review on carbohydrate embedded polyurethanes: An emerging area in the scope of biomedical applications
    Carbohydr. Polym. (IF 4.811) Pub Date : 2017-11-16
    Archana Solanki, Manita Das, Sonal Thakore

    Polyurethanes (PUs) are expanding to newer horizons in the field of biomedical sciences, particularly due to their exceptional set of properties that deem fit for applications in the said field. On the other hand, carbohydrates find increasing attention as components of biomedical devices due to their easy availability from renewable resources. The manipulation of PUs by carbohydrate has solved the major concern of biodegradability, biocompatibility and economy. This review summarizes the recent trends in PUs embedded with carbohydrates ranging from monosaccharide to polysaccharides, including supramolecular host such as cyclodextrin etc. Diverse approaches for embedding them in PUs in various forms have been listed. In recent decade, significant research has been carried out to employ such polymers in biomedical applications such as drug delivery devices, implants, scaffolds for tissue engineering etc. This knowledge could facilitate the selection of more efficient approach for synthesis of polymeric systems based on the biological macromolecules.

    更新日期:2017-11-20
  • Co-encapsulation of curcumin and resveratrol into novel nutraceutical hyalurosomes nano-food delivery system based on oligo-hyaluronic acid-curcumin polymer
    Carbohydr. Polym. (IF 4.811) Pub Date : 2017-11-16
    Chunjing Guo, Jungang Yin, Daquan Chen

    In this work, in order to enhance the stability, bioavailability and antioxidant activity of insoluble antioxidants used into juice, yoghourt and nutritional supplements, the oligo-hyalurosomes nano-delivery system (CRHs) based on oligo-hyaluronic acid −curcumin (oHC) polymer loaded curcumin(Cur) and resveratrol (Res) was fabricated with new nanotechnolgy. The rosy biodegradable amphiphilic oHC polymer was successfully synthesized and used to fabricate the hyalurosomes containing both Cur and Res, called CRHs. The CRHs can spontaneously self-assemble into nano-sized spherical shape of average particle size 134.5 ± 5.1 nm and Zeta potential −29.4 ± 1.2 at pH 7.4 PBS conditions. In vitro gastrointestinal release test showed a perfect stability and outstanding sustained release character. Moreover, compared to the single formulations and liposomes, CRHs showed a dose-dependent manner with a higher radical scavenging activity. Therefore, the novel CRHs nano-food manifested the hopeful properties for the new effective gastrointestinal formulation and promising new nano-food delivery system in the use of juice, yoghourt and nutritional supplements.

    更新日期:2017-11-20
  • Synthesis and characterization of Locust Bean Gum derivatives and their application in the production of nanoparticles
    Carbohydr. Polym. (IF 4.811) Pub Date : 2017-11-16
    Luis Braz, Ana Grenha, Marta C. Corvo, João Paulo Lourenço, Domingos Ferreira, Bruno Sarmento, Ana M. Rosa da Costa

    The development of LBG-based nanoparticles intending an application in oral immunization is presented. Nanoparticle production occurred by mild polyelectrolyte complexation, requiring the chemical modification of LBG. Three LBG derivatives were synthesized, namely a positively charged ammonium derivative (LBGA) and negatively charged sulfate (LBGS) and carboxylate (LBGC) derivatives. These were characterized by Fourier-transform infrared spectroscopy, elemental analysis, nuclear magnetic resonance spectroscopy, gel permeation chromatography, and x-ray diffraction. As a pharmaceutical application was aimed, a toxicological analysis of the derivatives was performed by both MTT test and LDH release assay. Several nanoparticle formulations were produced using LBGA or chitosan (CS) as positively charged polymers, and LBGC or LBGS as negatively charged counterparts, producing nanoparticles with adequate properties regarding an application in oral immunization.

    更新日期:2017-11-20
  • Effect of guar gum and salt concentrations on drag reduction and shear degradation properties of turbulent flow of water in a pipe
    Carbohydr. Polym. (IF 4.811) Pub Date : 2017-11-16
    Kamaljit Singh Sokhal, Dasaroju Gangacharyulu, Vijaya Kumar Bulasara

    Concentrated solutions of guar gum in water (1000–3000 ppm) with and without KCl salt (1000–4000 ppm) were injected near the wall for a short period (2.5 min) to investigate their effect on drag reduction in turbulent flow of water through a pipe (Re ≈ 17000–45000). Relative to bulk solution, the concentrations of polymer and salt were 50–150 ppm and 50–200 ppm, respectively. A drag reduction of 71.45% was observed for 3000 ppm of biopolymer without salt. Guar gum experienced mechanical degradation under high shear conditions and addition of KCl improved shear stability up to 47% (for Re ≈ 45000). A polymer concentration of 3000 ppm and salt concentration of 2000 ppm in the injection fluid were found to be optimum for achieving the highest drag reduction with better shear stability. Results indicated that boundary layer injection shows better drag reduction ability than pre-mixed solutions.

    更新日期:2017-11-17
  • Effects of chitosan molecular weight on its antioxidant and antimutagenic properties
    Carbohydr. Polym. (IF 4.811) Pub Date : 2017-11-16
    Shun-Hsien Chang, Chien-Hui Wu, Guo-Jane Tsai

    Chitosan (300.0 kDa) was enzymatically degraded to obtain six degraded chitosans with molecular weights (MWs) of 156.0, 72.1, 29.2, 7.1, 3.3, and 2.2 kDa. The antioxidant and antimutagenic properties of all seven chitosan samples were evaluated in vitro. The antioxidant scavenging activities of chitosans on hydrogen peroxide and 2, 2-diphenyl-1-picryl hydrazyl radical, and on chelating ferrous ion were significantly increased with chitosan’s decreasing MW, with 2.2-kDa chitosan have the highest impact. All seven chitosan samples exhibited strong anitmutagenic effects against direct (4- nitroquinoline 1-oxide) and indirect (benzo[α]pyrene) mutagens in the presence of rat liver enzyme S9 mix in Salmonella typhimurium TA 98 and TA 100. The effect of MW on antimutagenicity was similar to that on antioxidant activity. The underlying mechanism for chitosan antimutagenicity proved to be its desmutagenic effect on mutagens.

    更新日期:2017-11-17
  • Variation in starch quality of carotenoids-rich cassava clones that exhibit resistance to cassava brown streak disease
    Carbohydr. Polym. (IF 4.811) Pub Date : 2017-11-15
    Evans Atwijukire, Joseph Fuuna Hawumba, Enoch Wembabazi, Ephraim Nuwamanya

    Provitamin A cassava clones that exhibit resistance to Cassava Brown Streak Disease (CBSD) were analysed for critical starch properties, to understand possible applications in food industry. Significant reductions in amylopectin (P ≤ 0.05) were observed with increased CBSD severity while amylose content did not vary significantly either with disease or with carotenoids level. Reductions were observed, for starch pasting temperature, peak time and peak area with increase in carotenoids content. This may imply reduction in energy required to make paste from provitamin A cassava, hence such varieties may require less cooking time than white root varieties. The key advantage would be reduced cost for processing. Peak time, setback viscosity, breakdown viscosity and peak area increased with increase in CBSD severity. This implies that starches from CBSD infected cassava are unstable during processing, which negatively affects their use in the food industry, with an increased energy cost to process such starches.

    更新日期:2017-11-17
  • Ultrasound Assisted Polyacrylamide Grafting on Nano-Fibrillated Cellulose
    Carbohydr. Polym. (IF 4.811) Pub Date : 2017-11-15
    Haleh Sanaeishoar, Maryam Sabbaghan, Dimitris S. Argyropoulos

    Polyacrylamide has been grafted onto nanofibrillated cellulose (NFC-g-PAM) under mild conditions. This was accomplished by developing and optimizing an ultrasound assisted protocol in the presence of potassium persulfate initiator. The synthesis was optimized on the basis of maximizing grafting percentage and grafting efficiency by varying the initiator and monomer concentration. The data shows that ultrasound has a profound effect in promoting the grafting of PAM onto NFC. The intended grafting was confirmed and the properties of the new co-polymers were examined by elemental analyses, Fourier transform infrared spectroscopy, thermogravimetric analysis (TGA), and scanning electron microscopy (SEM). Intrinsic viscosity determinations in 0.1 M cupriethylenediamine solutions for the NFC-g-PAM copolymers and the starting NFC and PAM homopolymer revealed that grafting of PAM onto nanofibrillated cellulose has a profound effect on the hydrodynamic characteristics of the graft polymers.

    更新日期:2017-11-17
  • Development of liquid repellent coating on cotton fabric by simple binary silanization with excellent self-cleaning and oil-water separation properties
    Carbohydr. Polym. (IF 4.811) Pub Date : 2017-11-15
    Anita Panda, Priya Varshney, Soumya S. Mohapatra, Aditya Kumar

    This paper aims to develop a facile and single step method for the fabrication of superhydrophobic coating on cotton fabric. The coating has been prepared by using two silane trichloro(octadecyl)silane and (pentaflurophenyl)triethoxy silane by solution immersion technique. The wettability, surface topography and chemical compostion of the cotton fabric before and after treatment were charecterized by contact angle measurement, scanning electron microscope, and energy dispersive X-ray spectrum, respectively. Additionally, the functional group present in coating was analysed by FT-IR spectra. The coated fabric shows a contact angle of 172.9 ± 3°, 169 ± 3° and 167 ± 3° for water, ethylene glycol and glycerol, respectively. The chemical stability of the coated sample has been evaluated by immersion of the sample in different pH solutions and different solvents, showing the excellent chemical stability of coating. Ultrasonication with water, detergent and petroleum ether, and water jet impact test reveals the mechanical stability of coating. The thermal stability of the coated fabric has been examined by annealing the sample at different temperature. Additionally, it shows resistance to stain and UV irradiation. Furthermore, the coated cotton fabric exhibits excellent self-cleaning and oil-water separation properties, which makes it suitable for industrial applications.

    更新日期:2017-11-17
  • Isolation and characterization of nanocrystalline cellulose from sugar palm fibres (Arenga Pinnata)
    Carbohydr. Polym. (IF 4.811) Pub Date : 2017-11-15
    R.A. Ilyas, S.M. Sapuan, M.R. Ishak

    Cellulose was extracted from sugar palm fibres (arenga pinnata) by conducting delignification and mercerization treatments. Subsequently, sugar palm nanocrystalline celluloses (SPNCCs) were isolated from the extracted cellulose with 60 wt% concentrated sulphuric acid. The chemical composition of sugar palm fibres were determined at different stages of treatment. Structural analysis was carried out by Brunauer-Emmett-Teller (BET), X-ray diffraction (XRD) and Fourier transform infrared spectroscopy (FT-IR). Morphological analysis of extracted cellulose and isolated nanocrystalline cellulose (NCCs) was investigated by using field emission scanning electron microscopy (FESEM), atomic force microscopy (AFM), and transmission electron microscopy (TEM). The thermal stability of sugar palm fibres at different stages of treatment was investigated by thermogravimetric analysis (TGA). The results showed that lignin and hemicellulose were removed from the extracted cellulose through the delignification and mercerization process, respectively. The isolated SPNCCs were found to have length and diameters of 130 ± 30 nm and 9 ± 1.96 nm, respectively.

    更新日期:2017-11-17
  • Physicochemical properties of black pepper (Piper nigrum) starch
    Carbohydr. Polym. (IF 4.811) Pub Date : 2017-11-15
    Fan Zhu, Reuben Mojel, Guantian Li

    Black pepper (Piper nigrum) is among the most popular spices around the world. Starch is the major component of black pepper. However, little is known about functional properties of this starch. In this study, swelling, solubility, thermal properties, rheology, and enzyme susceptibility of 2 black pepper starches were studied and compared with those of maize starch. Pepper starch had lower water solubility and swelling power than maize starch. It had higher viscosity during pasting event. In dynamic oscillatory analysis, pepper starch had lower storage modulus. Thermal analysis showed that pepper starch had much higher gelatinization temperatures (e.g., conclusion temperature of 94 °C) than maize starch. The susceptibility to α-amylolysis of pepper starch was not very different from that of maize starch. Overall, differences in the physicochemical properties of the 2 pepper starches are non-significant. The relationships between structure (especially amylopectin internal molecular structure) and properties of starch components are highlighted.

    更新日期:2017-11-17
  • Non-leaching antibacterial cellulose triacetate reverse osmosis membrane via covalent immobilization of quaternary ammonium cations
    Carbohydr. Polym. (IF 4.811) Pub Date : 2017-11-14
    Pengfei Fei, Liang Liao, Jianqiang Meng, Bowen Cheng, Xiaoyu Hu, Jun Song

    A novel procedure to fabricate quaternized cellulose triacetate reverse osmosis (QCTA-RO) membranes via the etherification procedure between partially hydrolyzed CTA-RO membrane and 3-chloro-2-hydroxypropyl-trimethyl ammonium chloride (CHPTAC) in alkaline solutions (pH = 9–11) for different reaction time (1, 2, 3 and 4 h) was proposed. The structure and performances of the obtained QCTA-RO membranes were characterized and their antibacterial performances against E. coli and S. aureus were evaluated through colony counting method. The results showed that quaternary amine group was successfully grafted on the surface of membrane via covalently bond without significant damage to morphology, mechanical performance and thermal stability. The permeation flux values increased with prolonging modification time to 3 h, while the salt rejection decreased slightly but remained above 92%. QCTA-RO membranes displayed good antibacterial activity against Gram-negative E. coli and Gram-positive S. aureus and their bactericidal rates were 78.7–89.0% and 64.7–76.6% respectively at the optimized modification time of 2–3 h.

    更新日期:2017-11-15
  • The characteristics of konjac glucomannan octenyl succinate (KGOS) prepared with different substitution rates
    Carbohydr. Polym. (IF 4.811) Pub Date : 2017-11-14
    Fan-Bing Meng, Yun-Cheng Li, Da-Yu Liu, Geng Zhong, Xiao-Qiang Guo

    The characteristics of octenyl succinic anhydride (OSA)-modified polysaccharide could be affected by its degree of reaction. Four konjac glucomannan octenyl succinate (KGOS) samples were prepared with different substitution rates (SRs) of 1.151%, 1.514%, 1.753% and 2.247%. The critical micelle concentration (CMC) of the four KGOS materials decreased with increasing SR. Fourier transform infrared (FT-IR) spectroscopy indicated that the increase in SR had little effect on the type of acyl peak. The viscosity test indicated that with SR increase, the viscosity increased slightly at low rotational speed. The emulsion capacity (EC) and stability (ES) also increased with increasing SR, but the extent of increase was not obvious when the SR exceeded 1.753%. A similar pattern was found in confocal scanning laser microscopy (CSLM) observations and ES tests of KGOS nanoemulsions. Considering the characteristics of KGOS and the economic benefits, it is preferable to prepare KGOS with an SR of 1.514% and additions of alkalizing agent and OSA (in proportion to konjac glucomannan (KGM), w/w) of 2% and 3%, respectively, during the KGOS preparation.

    更新日期:2017-11-15
  • Modification of Cellulose Foam Paper for Use as a High-quality Biocide Disinfectant Filter for Drinking Water
    Carbohydr. Polym. (IF 4.811) Pub Date : 2017-11-13
    Solmaz Heydarifard, Kapila Taneja, Gaurav Bhanjana, Neeraj Dilbaghi, Mousa M. Nazhad, Ki-Hyun Kim, Sandeep Kumar

    Development of a foam-formed cellulose filter paper with high wet strength was carried out for application as a drinking water filter. The wet strength and antimicrobial activity of cellulose foam paper against several bacteria species (Bacillus subtilis MTCC 441 (Gram +ve), B. cereus NCDC 240 (Gram +ve), Pseudomonas aeruginosa NCDC 105 (Gram −ve), Klebsiella pneumonia NCDC 138 (Gram −ve), and Escherichia coli MTCC 40 (Gram −ve)) were investigated. The morphology and structure of the cellulose foam paper was characterized using scanning electron microscopy (SEM). The results of our study confirmed that glutaraldehyde solution or 1,2,3,4-butanetetracarboxylic acid (BTCA) added to cellulose foam paper pretreated with cationic polyacrylamide (C-PAM) provided very high and stable wet strength performance together with excellent antimicrobial properties.

    更新日期:2017-11-14
  • Sequencing the oligosaccharide pool in the low molecular weight heparin dalteparin with offline HPLC and ESI-MS/MS
    Carbohydr. Polym. (IF 4.811) Pub Date : 2017-11-13
    Zhangjie Wang, Tianji Zhang, Shaoshuai Xie, Xinyue Liu, Hongmei Li, Robert J. Linhardt, Lianli Chi

    Low molecular weight heparins (LMWHs) are widely used anticoagulant drugs. The composition and sequence of LMWH oligosaccharides determine their safety and efficacy. The short oligosaccharide pool in LMWHs undergoes more depolymerization reactions than the longer chains and is the most sensitive indicator of the manufacturing process. Electrospray ionization tandem mass spectrometry (ESI-MS/MS) has been demonstrated as a powerful tool to sequence synthetic heparin oligosaccharide but never been applied to analyze complicated mixture like LMWHs. We established an offline strong anion exchange (SAX)-high performance liquid chromatography (HPLC) and ESI-MS/MS approach to sequence the short oligosaccharides of dalteparin sodium. With the help of in-house developed MS/MS interpretation software, the sequences of 18 representative species ranging from tetrasaccharide to octasaccharide were obtained. Interestingly, we found a novel 2,3-disulfated hexauronic acid structure and reconfirmed it by complementary heparinase digestion and LC-MS/MS analysis. This approach provides straightforward and in-depth insight to the structure of LMWHs and the reaction mechanism of heparin depolymerization.

    更新日期:2017-11-14
  • Environment-Friendly Urea-oxidized starch Adhesive with Zero Formaldehyde-emission
    Carbohydr. Polym. (IF 4.811) Pub Date : 2017-11-12
    Xiang-fei Zhao, Lan-qin Peng, Hong-ling Wang, Yan-bin Wang, Hong Zhang

    This study reports on an environment-friendly renewable and zero formaldehyde-emission urea-oxidized starch (U-OSt) adhesive based on native corn starch. The adhesive was prepared by polycondensation reaction of oxidized starch and urea. The morphology, molecular structure, crystalline structure, shear strength and viscosity of the adhesive, the native and oxidized starch were instrumentally investigated. The influence of processing factors were studied, such as the oxidizer content, the urea content and the addition of titanium dioxide nanoparticle (nano-TiO2). The results show the adhesive has an excellent comprehensive performance at urea content of 50% (w/w, dry starch basis) while 5.0% (w/w, dry starch basis) KMnO4 as oxidizer. The dry shear strength was increased by 16.9% by adding of nano-TiO2 content of 1.5% (w/w, dry starch basis), and the corresponding viscosity was 4100 mPa·s. It is found appropriate amount of nano-TiO2 played a complementary effect between adhesive and adherend, which enhanced the adhesive property and stability of adhesive.

    更新日期:2017-11-13
  • Evaluation of nisin-loaded chitosan-monomethyl fumaric acid nanoparticles as a direct food additive
    Carbohydr. Polym. (IF 4.811) Pub Date : 2017-11-11
    Imran Khan, Charles Nkufi Tango, Sumaira Miskeen, Deog-Hwan Oh

    Nisin-loaded chitosan-monomethyl fumaric acid (CM-N) nanoparticles were evaluated as a novel, direct food additive. Chitosan (CS) was modified with monomethyl fumaric acid (MFA) in the presence of 1-ethyl-3-(3-dimethylaminopropyl) carbodiimide (EDC). CS-loaded nisin (CS-N) and CM-N nanoparticles were produced through ionic interactions between the positive amino group of CS and CS-MFA and negative tripolyphosphate ions. The resultant materials were characterized by TNBS assay, X-ray diffraction, Fourier-transform infrared spectroscopy, scanning electron microscopy, thermogravimetric analysis, and zeta potential analysis. CS-MFA was successfully synthesized with 8.38 ± 0.02% substitution of the amino groups, as confirmed by TNBS assay. The percentage yield of CS-N and CM-N nanoparticles was 81.64 and 76.83% and nisin encapsulation efficiency was 71.48 ± 0.48 and 60.32 ± 0.63%, respectively. The average particle size of CS-N and CM-N nanoparticles was 134.3 and 207.9 nm, while the zeta potential of CS-N and CM-N nanoparticles was +39.4 mV and +31.5 mV, respectively. Upon antibacterial activity against foodborne pathogens, CM-N significantly reduced bacterial counts compared to the other tested samples in orange juice after 48 h of incubation. Based on the preliminarily results, CM-N nanoparticles have shown impressive properties and can be used in the food industry as carriers and direct antimicrobial agents.

    更新日期:2017-11-13
  • Preparation and characterization of tree-like cellulose nanofiber membranes via the electrospinning method
    Carbohydr. Polym. (IF 4.811) Pub Date : 2017-11-11
    Kai Zhang, Zongjie Li, Weimin Kang, Nanping Deng, Jing Yan, Jingge Ju, Yong Liu, Bowen Cheng

    A novel tree-like cellulose nanofiber membrane was controllably fabricated via the electrospinning method by adding certain amount of tetra butyl ammonium chloride (TBAC) into the cellulose acetate solution followed by a deacetylation treatment process. The morphological structure, material structure and air filtration performance of both the cellulose and the cellulose acetate tree-like nanofiber membranes were characterized. Water contact angles, mechanical properties, and air filtration properties were also evaluated. The air filtration efficiency of cellulose acetate tree-like nanofiber membrane can reached 99.58%, and the eventually cellulose tree-like membrane still maintain 98.37%. The eventual cellulose tree-like nanofiber membranes exhibited small pore size, excellent hydrophilicity, good solvent resistance and preferable mechanical property. The small average pore size caused by the tree-like structure and the strong resistance to organic solvent can make it a potential candidate for the membrane separation.

    更新日期:2017-11-13
  • Valorization of peanut shells: manufacture of bioactive oligosaccharides
    Carbohydr. Polym. (IF 4.811) Pub Date : 2017-11-11
    Xiana Rico, Beatriz Gullón, José Luis Alonso, Juan Carlos Parajó, Remedios Yáñez

    Peanut shells were subjected to non-isothermal aqueous treatments to cause the partial breakdown of hemicelluloses into soluble oligosaccharides and lignin-derived compounds with high antioxidant activity. The effects of temperature on the chemical composition of the substrate and soluble reaction products were assessed. Under selected conditions (210 °C, severity = 4.09), the overall amount of poly- and oligo- saccharides present in the liquid phase reached 9.8 g/L. This solution was refined by consecutive stages of discontinuous diafiltration, yielding a refined product containing about 72.4 wt % of oligomers at a global yield of 8.5 kg/100 kg oven-dry PS. The purified products were characterized by HPLC, MALDI-TOF-MS and FTIR, confirming the major reaction products were saccharides made up of xylose with degrees of polymerization up to 17, substituted with acetyl and methylglucuronosyl groups, for which a number of pharmaceutical and food applications have been proposed. Solubilization of hemicelluloses in the treatments resulted in the production of solids enriched in cellulose and lignin suitable for further applications.

    更新日期:2017-11-11
  • Antihyperlipidemic and hepatoprotective activities of polysaccharide fraction from Cyclocarya paliurus in high-fat emulsion-induced hyperlipidaemic mice
    Carbohydr. Polym. (IF 4.811) Pub Date : 2017-11-10
    Zhanwei Yang, Jin Wang, Jingen Li, Lei Xiong, Hui Chen, Xin Liu, Ning Wang, Kehui Ouyang, Wenjun Wang

    The objective of this study was to analyse the structure of CPP-2, and to observe the pharmacological effects of CPP-2 on lipid metabolism and oxidative stress. CPP-2, eluted as two main fractions comprised of two polysaccharides with Mw of 307 and 3.7 kDa, was mainly consisted of rhamnose, mannose, glucose and galactose in a molar ratio of 1.00:0.78:3.22:0.45. The results showed that treatment with CPP-2 could improve blood lipid levels (TC, TG, HDL-C and LDL-C), liver lipid levels (TC and TG) and antioxidant status (SOD, T-AOC, GSH-PX, MDA and LPO). In addition, the histopathological observations of mice livers and the GPT activities indicated that CPP-2 could attenuate liver cell injury. The present findings demonstrated that CPP-2 might be effective in lowering lipid and protecting against HFE-induced hyperlipidemia and non-alcoholic fatty liver.

    更新日期:2017-11-11
  • A Novel Wound Dressing Based on a Konjac Glucomannan/Silver Nanoparticle Composite Sponge Effectively Kills Bacteria and Accelerates Wound Healing
    Carbohydr. Polym. (IF 4.811) Pub Date : 2017-11-10
    Honglei Chen, Guangqian Lan, Luoxiao Ran, Yang Xiao, Kun Yu, Bitao Lu, Fangying Dai, Dayang Wu, Fei Lu

    A novel Konjac glucomannan/silver nanoparticle (KGM/AgNP) composite sponge was successfully prepared via a simple 2-step method for biomedical applications as wound-healing materials. First, AgNPs were prepared with green deoxidizer egg white. Then, KGM powder was added to the AgNP solution and stirred vigorously, and the composite sponge was obtained by freeze-drying. The KGM/AgNP composite sponge showed excellent water absorption and water retention, and considerable mechanical properties. KGM/AgNP composite sponges displayed good antibacterial activity against test microorganisms. In vitro cytocompatibility testing showed that L929 cells could survive well in the presence of KGM/AgNPs, indicating that KGM/AgNPs have good cytocompatibility. Animal models showed that the KGM/AgNP composite sponges effectively accelerated wound healing, and histological findings showed that they promoted fibroblast growth and accelerated epithelialization. The experimental results showed that KGM/AgNP composite sponges have great potential in promoting wound healing.

    更新日期:2017-11-10
  • Reduction stimuli-responsive unimolecular polymeric prodrug based on amphiphilic dextran-framework for antitumor drug delivery
    Carbohydr. Polym. (IF 4.811) Pub Date : 2017-11-09
    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 23 wt%), adjustable proportion of hydrophobic and hydrophobic portions, superior stability in aqueous solution, and easy access to cells. Introduction of a disulfide bond linker between the drug and the carrier can realize the function of reduction-responsive controlled drug-release. The experimental study indicated that the prodrug exhibited notable antitumor activity against HeLa cells and MCF-7 cells in vitro. Compared to similar DCO prodrug based on double carbon bond, the disulfide bond-conjugated DCO prodrug induced higher level of tumor cell apoptosis. Considering the drug-loading efficiency, micellar stability, cost of preparation and controlled drug release, the presented prodrug is more advantageous than traditional unimolecular prodrug and represents a promising approach for design of stimuli-responsive polymeric prodrug for effective cancer therapeutics.

    更新日期:2017-11-10
  • Fabrication of chitosan-mesoporous silica SBA-15 nanocomposites via functional ionic liquid as the bridging agent for PPL immobilization
    Carbohydr. Polym. (IF 4.811) Pub Date : 2017-11-09
    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. The properties of immobilized enzyme (SBA-CIL-CS-PPL) such as activity, stability and reusability have been significantly improved, and a preferable pH and temperature tolerance were obtained as well. Results demonstrated the inorganic-organic nanocomposite could be used as an ideal support for enzyme immobilization.

    更新日期:2017-11-10
  • The Development of An Alginate/Polycaprolactone Composite Scaffold for in situ Transfection Application
    Carbohydr. Polym. (IF 4.811) Pub Date : 2017-11-08
    Wei-Wen Hu, Yun-Chung Wu, Zhe-Chen Hu

    Alginate and polycaprolactone (PCL) were coelectrospun using a dual-jet system to prepare composite nanofibers in defined ratios, and hence both chemical properties and hydrophobicity of scaffolds can be manipulated. These nanofibers were applied in gene immobilization: positive charged polyethyleneimine (PEI)/DNA polyplexes were adsorbed onto anionic alginate fibers, and the higher ratios of alginate resulted in the more immobilized nonviral vectors. Through the incorporation of PCL, biocompatibility of scaffolds was highly improved. Finally, these scaffolds were used for in situ transfection application. Compared to pure alginate fibers, composite fibers not only successfully transferred target genes to adhered cells but also enhanced cell morphology and viability, suggesting that alginate/PCL nanofibers were multifunctional with gene delivery capability and biocompatibility, and the manipulation of their composition can balance and optimize both requirements. To our knowledge, this approach might be the first one using electrostatic interactions to immobilize genes onto nanofibrous scaffolds for in situ transfection application.

    更新日期:2017-11-10
  • Synergistic effect of carbon nanotubes and graphene for high performance cellulose acetate membranes in biomedical applications
    Carbohydr. Polym. (IF 4.811) Pub Date : 2017-11-08
    Mariana Ioniță, Livia Elena Crică, Stefan Ioan Voicu, Sorina Dinescu, Florin Miculescu, Marieta Costache, Horia Iovu

    Comparative evaluation of innovative combinations of three types of carbon nanomaterial (CNM) highlighted membranes with important potential for biomedical applications. Non-solvent induced phase separation coupled with ultrasound technique was used to generate membranes comprised of (i) cellulose acetate/ammonia functionalized carbon nanotubes (CA/CNT), (ii) cellulose acetate/ammonia functionalized graphene oxide (CA/GO), and (iii) cellulose acetate/CNT-GO. Structural, topographical and thermal features as well as water and ethanol permeation, bovine serum albumin (BSA) and haemoglobin (Hb) rejection were evaluated. Biocompatibility in terms of cytotoxicity, cell proliferation and adhesion were explored using a 3T3E1 cell line. The formation of amorphous structures, within which the CNMs were well dispersed, facilitated the development of smoother topographies. Addition of CNMs generated morphological changes influencing a decrease in water and ethanol fluxes. Furthermore, CNMs concentrated within the membrane skin layer exhibited repellent effects against BSA and Hb molecules and excellent cytocompatibility.

    更新日期:2017-11-10
  • Synergistic effects of graft polymerization and polymer blending on the flexibility of xylan-based films
    Carbohydr. Polym. (IF 4.811) Pub Date : 2017-11-08
    Xueqin Zhang, Chuanfu Liu, Aiping Zhang, Runcang Sun

    To develop functional and sustainable films from xylan-based hemicelluloses, beechwood xylan was firstly modified with p-dioxanone (PDO) through ring-opening graft polymerization (ROGP) and then reinforced by poly(vinyl alcohol) (PVA) to fabricate xylan-graft-poly(p-dioxanone)/PVA (XGP/PVA) ternary composite films. FT-IR spectra proved the existence of intermolecular hydrogen bonding interactions between the hydroxyl groups of XGP and PVA. SEM analysis outlined the good compatibility between the XGP matrix and the PVA filler in blending films. From DSC data, the miscibility between XGP and PVA led to increase in the glass transition temperature (Tg) and the crystallinity (Xc) of XGP. In addition, XRD analysis also revealed the increased Xc of XGP in the presence of PVA, which was consistent with the DSC results. TGA/DTG curves indicated that the addition of PVA improved the thermal stability of XGP. Tensile testing showed a dramatic increase in the elongation at break of films with the development of weight percent gain (WPG) of XGP.

    更新日期:2017-11-10
  • Chitosan-based polymer hybrids for thermo-responsive nanogel delivery of curcumin
    Carbohydr. Polym. (IF 4.811) Pub Date : 2017-11-07
    Jittima Amie Luckanagul, Chutamart Pitakchatwong, Pahweenvaj Ratnatilaka Na Bhuket, Chawanphat Muangnoi, Pranee Rojsitthisak, Suwabun Chirachanchai, Qian Wang, Pornchai Rojsitthisak

    The purpose of this study is to design, develop thermoresponsive nano-sized hydrogel particles from a natural polymer, chitosan, as smart material platforms for curcumin delivery. Chitosan was used as the backbone material to be grafted with poly-(N-isopropylacrylamide) (pNIPAM) using an EDC/NHS peptide coupling reaction. The conjugated products were characterized by 1H NMR and TGA. Chitosan-grafted pNIPAM (CS-g-pN) nanogels were prepared by a sonication method. The loading of curcumin into the CS-g-pN nanogels was achieved using an incubation method. Size, morphology of nanogels, amounts of curcumin loaded to the nanogels and cellular uptake were investigated by DLS, TEM, fluorescent spectroscopy and confocal microscopy techniques, respectively. A CellTiter-Blue® cell viability assay was performed in NIH-3T3 and HeLa cells to assess the safety while MTT assay was carried out in MDA-231, Caco-2, HepG2, and HT-29 cells for determining cytotoxic effects. Results showed that CS-g-pN with 3-60% degree of modification were simply assembled into spherical nanogel particles with submicron sizes, in which curcumin was encapsulated. The thermoresponsive behavior of each CS-g-pN nanogel formulation differed due to the grafted pNIPAM length and density. The CS-g-pN nanogel formulations were non-toxic towards NIH-3T3 and HeLa cells. Each curcumin-loaded CS-g-pN nanogel formulation could be up taken into NIH-3T3 cell lines and showed the dose-dependent cytotoxicity against tested cell lines. Successful development of this curcumin-loaded nanogel will lead to advanced materials that can be functionalized and optimized for targeted therapy and controlled delivery of small molecules and/or biomolecules for biomedical applications.

    更新日期:2017-11-10
  • Structural characterization and osteogenic bioactivity of a sulfated polysaccharide from pacific abalone (Haliotis discus hannai Ino)
    Carbohydr. Polym. (IF 4.811) Pub Date : 2017-11-06
    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, and 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 were also found. AGSP possessed a sulfate content of 12.4% with a relative molecular weight of 6.6 kDa. AGSP strengthened alkaline phosphatase activity induced by BMP-2 in a dose dependent manner at 10–200 μg/mL with 425% enhancement being observed at 200 μg/mL, indicating AGSP could be an adjuvant candidate to enhance osteogenic activity of BMP-2.

    更新日期:2017-11-10
  • A novel voltammetric sensor for the simultaneous detection of Cd2+ and Pb2+ using graphene oxide/κ-carrageenan/L-cysteine nanocomposite
    Carbohydr. Polym. (IF 4.811) Pub Date : 2017-11-06
    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 5–50 nM with the detection limits as 0.58 nM and 1.08 nM respectively. The sensitivity calculated from the slope of calibration curve was 1.39 μA/nM and 1.32 μA/nM for Cd2+ and Pb2+ respectively. We also carried out multiple metal ion detection, interference of anions and surfactants for the detection of Cd2+ and Pb2+ ions. The modified electrode has been applied to the detection of Cd2+ and Pb2+ present in water and milk samples, and the accessed results were satisfactory with that of AAS.

    更新日期:2017-11-10
  • Chitosan oligosaccharide-N-chlorokojic acid mannich base polymer as a potential antibacterial material
    Carbohydr. Polym. (IF 4.811) Pub Date : 2017-11-06
    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. Besides, COS-N-MB can interact with membrane proteins, causing deformation in the structure and functionality. The good biocompatibility, noncytotoxic, and low hemolysis made this novel material a promising and effective compound for antibacterial applications.

    更新日期:2017-11-10
  • Budesonide nanocrystal-loaded hyaluronic acid microparticles for inhalation: in vitro and in vivo evaluation
    Carbohydr. Polym. (IF 4.811) Pub Date : 2017-11-04
    Tingting Liu, Meihua Han, Fang Tian, Dongmei Cun, Jukka Rantanen, Mingshi Yang

    Most inhaled pharmaceutical formulations on the market are intended to exert immediate pharmacological action, even although inhaled sustained-release formulations can be needed to reduce the frequency of dosing. The purpose of this study was to investigate the pulmonary retention and pharmacokinetics of a poorly water-soluble drug after loading its nanocrystal form into inhalable mucoadhesive microparticles composed of hyaluronic acid. It was intended to prolong the pharmacological effect without compromising the dissolution rate of the poorly water-soluble drug. In this study, budesonide, a corticosteroid anti-inflammatory drug, was used as a model poorly water-soluble drug. Submicron budesonide particles were prepared by wet ball milling, and subsequently loaded into hyaluronic acid microparticles by the spray drying process. The ball-milled budesonide particles and the spray-dried microparticles were characterized using dynamic light scattering (DLS), laser diffraction, Scanning electron microscopy (SEM), X-ray powder diffraction (XRD) and differential scanning calorimetry (DSC). Selected formulations were evaluated in terms of their dissolution/release rate, aerosol performance, muco-adhesion and pharmacokinetics in rats. As shown by XRD and DSC analysis, the nanonized budesonide particles in this study were mainly in crystalline form. The dissolution/release study showed that the in vitro release of budesonide from the microparticles was not significantly sustained compared with the dissolution rate of budesonide nanocrystals (BUD-NC). However, the budesonide in the microparticles exhibited prolonged retention on the surface of porcine tracheal tube owing to the muco-adhesion ability of hyaluronic acid. After intratracheal administration to rats, the BUD-NC exhibited a similar pharmacokinetic profile to that of budesonide solution via i.v. injection. In contrast, budesonide loaded in the mucoadhesive microparticles exhibited a significantly prolonged Tmax and increased bioavailability with the animal model. This study demonstrated that inhaled microparticles composed of hyaluronic acid could produce sustained budesonide pharmacological effects. This can be attributed to the mucoadhesion of the polymer that overcame the mucociliary clearance and, consequently, prolonged the retention of the active substance in the lung without necessarily reducing the in vitro dissolution rate.

    更新日期:2017-11-10
  • Efficient gene delivery by oligochitosan conjugated serum albumin: Facile synthesis, polyplex stability, and transfection
    Carbohydr. Polym. (IF 4.811) Pub Date : 2017-11-04
    Monika Kumari, Chi-Hsien Liu, Wei-Chi Wu

    Chitosan and its derivatives have shown to be potential gene carriers with biocompatiblility and safety. However, their practical delivery is far from being ideal because of the low transfection efficiency. The present work describes the potential of a natural protein, bovine serum albumin (BSA), conjugated with a natural oligosaccharide, oligochitosan (OC), as a considerable promising approach for a safe and efficient non-viral gene delivery vector. The FTIR spectra proved the effective conjugation of BSA with OC through covalent bond. The condensation ability of plasmid DNA (pDNA) with a BSA-OC biopolymer was analyzed by gel retardation assay, competition binding assay, and dynamic light scattering used to measure the nanoparticle size. In addition, the BSA-OC biopolymer showed the protection of pDNA from enzymatic degradation by DNase I and showed good stability when exposed to 50% fetal bovine serum. The transfection efficiency was evaluated in the presence of 10% serum-supplemented media or serum-free media on three kinds of mammalian cells. Our results showed that the BSA-OC biopolymer is a good non-viral vehicle for gene delivery. We investigated the parameters such as the pDNA payload, temperature, incubating duration, and biopolymer/pDNA ratio on the transfection efficiency. This hybrid vehicle had the ability to transfect 90% of cells and to maintain 80% of cell viability. The aforementioned results suggest that the facile synthesis of the BSA-OC biopolymer could overcome the cytotoxicity problem and transfection barriers during in vitro gene delivery.

    更新日期:2017-11-10
  • Ulvan-Chitosan Polyelectrolyte Complexes as Matrices for Enzyme Induced Biomimetic Mineralization
    Carbohydr. Polym. (IF 4.811) Pub Date : 2017-11-03
    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.

    更新日期:2017-11-10
  • A chitin deacetylase of Podospora anserina has two functional chitin binding domains and a unique mode of action
    Carbohydr. Polym. (IF 4.811) Pub Date : 2017-11-03
    Janina Hoßbach, Franziska Bußwinkel, Andreas Kranz, Jasper Wattjes, Stefan Cord-Landwehr, Bruno M. Moerschbacher

    Chitosan is a structurally diverse biopolymer that is commercially derived from chitin by chemical processing, but chitin deacetylases (CDAs) potentially offer a sustainable and more controllable approach allowing the production of chitosans with tailored structures and biological activities. We investigated the CDA from Podospora anserina (PaCDA) which is closely related to Colletotrichum lindemuthianum CDA in the catalytic domain, but unique in having two chitin-binding domains. We produced recombinant PaCDA in Hansenula polymorpha for biochemical characterization and found that the catalytic domain of PaCDA is also functionally similar to C. lindemuthianum CDA, though differing in detail. When studying the enzyme’s mode of action on chitin oligomers by quantitative mass-spectrometric sequencing, we found almost all possible sequences up to full deacetylation but with a clear preference for specific products. Deletion muteins lacking one or both CBDs confirmed their proposed function in supporting the enzymatic conversion of the insoluble substrate colloidal chitin.

    更新日期:2017-11-10
  • Factors affecting the properties of nitrocellulose emulsions: A comparative study
    Carbohydr. Polym. (IF 4.811) Pub Date : 2017-11-02
    Fatemeh Fallah, Manouchehr Khorasani, Morteza Ebrahimi

    In this study the influence of viscosity and chemical nature of dispersed phase, preparation conditions and storage temperature on the properties of nitrocellulose emulsions produced by gel emulsification (G) and direct mechanical emulsification (D) methods were examined. Chemical nature of dispersed phase had no effect on the drop size for both methods; however it had a significant effect on emulsion stability. Viscosity of dispersed phase did not considerably affect drop breakage process in route G, while strongly affected drop breakage in route D. Addition rate had no significant effect on the drop size produced by route D; while for route G high addition rate resulted in catastrophic phase inversion. The drop size produced by route D decreased dramatically by increasing stirring speed, whereas stirring speed had a minimal effect on the drop breakage process in route G. Finally, it was found that emulsion stability was greatly influenced by storage temperature.

    更新日期:2017-11-10
  • A novel structural fucosylated chondroitin sulfate from Holothuria Mexicana and its effects on growth factors binding and anticoagulation
    Carbohydr. Polym. (IF 4.811) Pub Date : 2017-11-02
    Qinying Li, Chao Cai, Yaoguang Chang, Fuming Zhang, Robert J. Linhardt, Changhu Xue, Guoyun Li, Guangli Yu

    Fucosylated chondroitin sulfate (FCS), a structurally distinct glycosaminoglycan from the body wall of sea cucumber, possesses many biological properties and pharmacology functions. The refined structure of FCS isolated from sea cucumber Holothuria Mexicana (FCShm) was characterized by NMR spectra and HILIC-FTMS, which demonstrated four types of branches in FCShm. Among these, two branches were α-L-Fuc-2S4S (where Fuc is fucose and S is sulfo) and α-L-Fuc-4S linked to O-3 of glucuronic acid residues, while others were identified as α-L-Fuc-4S and α-L-Fuc-3S4S attached to O-6 of N-acetylgalactosamine residue. Furthermore, the fucosyl branches were α-1,3-linked with different degree of polymerization from 1 to 5. FCShm exhibited high affinity to fibroblast growth factor 1 and 2, growth factors involved in neovascularization. Moreover, FCShm displayed intrinsic anticoagulant activity and inhibited thrombin and factor Xa activation by antithrombin III. Our results proposed a novel structural FCS and demonstrated its favorable application prospects in anti-angiogenesis and anticoagulation.

    更新日期:2017-11-10
  • Structural characterization and thermal behavior of a gum extracted from Ferula assa foetida L.
    Carbohydr. Polym. (IF 4.811) Pub Date : 2017-10-31
    Sima Saeidy, Ali Nasirpour, Javad Keramat, Jacques Desbrières, Didier Le Cerf, Guillaume Pierre, Cedric Delattre, Céline Laroche, Hélène De Baynast, Alina-Violeta Ursu, Alain Marcati, Gholamreza Djelveh, Philippe Michaud

    The gum asafoetida, an oleo-gum-resin from root of Ferula assa foetida, was extracted through alcoholic procedure followed by water extraction and then biochemically characterized using colorimetric assays, Fourier infrared spectroscopy, gas chromatography coupled to mass spectrometry, and 1D and 2D nuclear magnetic resonance. The gum was mainly composed of carbohydrates (67.39% w/w) with a monosaccharide distribution of 11.5: 5.9: 2.3: 1 between Gal, Ara, Rha and GlcA (molar ratio) and proteins (arabinogalactan protein). The polysaccharide consisted of a (1 → 3)-β-d-galactan backbone ramified predominantly from O-6 but also from O-4 and O-4,6. Side chains included terminal-α-l-Araf, terminal-α-l-Rhap, (1 → 3)-α-l-Araf, (1 → 5)-α-l-Araf, terminal-β-d-Galp, β-d-GlcA and traces of (1 → 4)-β-d-GlcA. X-ray diffraction pattern showed a semi crystalline microstructure. Thermal behavior of the gum was evaluated by thermogravimetric analysis (TGA) and differential scanning calorimetry (DSC) revealed temperatures below and upper 200 °C as dominant regions of weight loss.

    更新日期:2017-11-01
  • 更新日期:2017-11-01
  • Synthesis and evaluation of chondroitin sulfate based hydrogels of loxoprofen with adjustable properties as controlled release carriers
    Carbohydr. Polym. (IF 4.811) Pub Date : 2017-10-31
    Ikrima Khalid, Mahmood Ahmad, Muhammad Usman Minhas, Kashif Barkat

    Mixtures of polymer (chondroitin sulfate) and monomer (AMPS) in the presence of co-monomer (MBA) were employed for the production of hydrogels, with adjustable properties, following free radical copolymerization. The hydrogel’s structural properties were assessed by FTIR, DSC, TGA, SEM and XRD which confirmed the development and stability of synthesized structure. The results from FTIR analysis showed that CS react with the AMPS monomer during the polymerization process and confirmed the grafting of AMPS chains onto CS backbone. The surface morphology of CS-co-poly(AMPS) hydrogels, as evident by SEM, corresponds to their improved swelling ability due to high porosity. Thermal analysis showed that crosslinking formed a stable hydrogel network is thermally more stable than its basic ingredients. The effects of pH revealed an increasing trend in swelling with increasing concentration of either CS or AMPS. In addition, different modalities for drug loading were studied with respect to drug homogeneous distribution; loxoprofen sodium was employed as model drug and was loaded by swelling-diffusion method. In vitro drug release profiles and kinetics were assessed to confirm their reproducibility and reliability. Higuchi model is the best fit model to explain drug release from formed gels indicating diffusion-controlled release. Similarly, Korsmeyer–Peppas model yields remarkably good adjustments where release kinetics involves a combination of diffusion in hydrated matrix and polymer relaxation. Conclusively, CS-co-poly(AMPS) hydrogels could be a potential alternate to conventional dosage forms for controlled delivery of loxoprofen sodium for extended period of time.

    更新日期:2017-11-01
  • Thermo-sensitive and swelling properties of cellouronic acid sodium/poly (acrylamide-co-diallyldimethylammonium chloride) semi-IPN
    Carbohydr. Polym. (IF 4.811) Pub Date : 2017-10-31
    Heng Zhang, Xin Gao, Keli Chen, Hui Li, Lincai Peng

    In current study, cellouronic acid sodium (CAS), obtained from bagasse pith, has been introduced into poly(acrylamide-co-diallyldimethylammonium chloride) (poly(AM-co-DAC)) network to form novel thermo-sensitive semi-IPNs. The structure and morphology of the hydrogels were proved by Fourier transformation infrared spectroscopy (FT-IR), X-ray photoelectron spectroscopy (XPS) and scanning electron microscopy (SEM). The effects of CAS content, initiator charge, cross-linker dosage and swelling-medium property on the thermo-responsive water absorptivity were investigated in detail. The results elucidated that the prepared gels exhibited a thermo-sensibility with an upper critical solution temperature (UCST) and a high water-absorbency. And the values of UCST and equilibrium swelling ratio largely depended on the inner structure of the semi-IPNs and the external solvent property. It was also revealed that the swelling process conformed to the Schott’s pseudo second order model and diffusion type was non-Fickian diffusion. The value of activation energy for this polyelectrolyte was found to be 8.74 kJ/mol.

    更新日期:2017-11-01
  • Cross-linked chitosan/β-cyclodextrin composite for selective removal of methyl orange: Adsorption performance and mechanism
    Carbohydr. Polym. (IF 4.811) Pub Date : 2017-10-31
    Yezhou Jiang, Bingchuan Liu, Jikun Xu, Keliang Pan, Huijie Hou, Jingping Hu, Jiakuan Yang

    A complex chitosan/β-cyclodextrin polymer was synthesized by bridging with maleoyl chains followed by cross-linking with glutaraldehyde. The adsorption performance of the synthetic polymer was investigated for the selective removal of methyl orange (MO) from aqueous solution. The kinetic behavior was well fitted by the pseudo-second order model, while the adsorption process at equilibrium followed the Langmuir isotherm model. The thermodynamic parameters suggested that the adsorption was exothermic and spontaneous. Under optimal adsorption conditions, the capacity for MO reached 392 mg/g with the dosage of 10 mg/50 mL. Based on the analysis from FTIR, 1H NMR, TGA and zeta potential, the adsorption mechanism could be explained by the synergistic effect of electrostatic attraction of amino groups from chitosan and host-guest interaction from β-cyclodextrin. This adsorbent also demonstrated high selectivity towards MO due to the unique structure of cross-linked chitosan/β-cyclodextrin polymer that are complementary to that of MO molecule.

    更新日期:2017-11-01
  • Structural Analysis and Biological Activity of a Highly Regular Glycosaminoglycan from Achatina fulica
    Carbohydr. Polym. (IF 4.811) Pub Date : 2017-10-29
    Jie Liu, Lutan Zhou, Zhicheng He, Na Gao, Feineng Shang, Jianping Xu, Zi Li, Zengming Yang, Mingyi Wu, Jinhua Zhao

    Edible snails have been widely used as a health food and medicine in many countries. A unique glycosaminoglycan (AF-GAG) was purified from Achatina fulica. Its structure was analyzed and characterized by chemical and instrumental methods, such as Fourier transform infrared spectroscopy, analysis of monosaccharide composition, and 1D/2D nuclear magnetic resonance spectroscopy. Chemical composition analysis indicated that AF-GAG is composed of iduronic acid (IdoA) and N-acetyl-glucosamine (GlcNAc) and its average molecular weight is 118 kDa. Structural analysis clarified that the uronic acid unit in glycosaminoglycan (GAG) is the fully epimerized and the sequence of AF-GAG is →4)-α-GlcNAc (1 → 4)-α-IdoA2S(1→. Although its structure with a uniform repeating disaccharide is similar to those of heparin and heparan sulfate, this GAG is structurally highly regular and homogeneous. Anticoagulant activity assays indicated that AF-GAG exhibits no anticoagulant activities, but considering its structural characteristic, other bioactivities such as heparanase inhibition may be worthy of further study.

    更新日期:2017-10-30
  • Chitosan based nano composite adsorbent—synthesis, characterization and application for adsorption of binary mixtures of Pb(II) and Cd(II) from water
    Carbohydr. Polym. (IF 4.811) Pub Date : 2017-10-29
    Jayabrata Maity, Samit Kumar Ray

    Composite type adsorbent was prepared by integrating chitosan (Cs) with crosslinked polymethacrylic acid (PMA) and nano sized halloysite nanotube (HNT). The structure of the resulting Cs-PMA/HNT adsorbents was characterized by FTIR, NMR, XRD, TGA, SEM/EDX and rheological properties. These functional adsorbents were used for removal of Pb(II) and Cd(II) as single and binary competitive mixtures from water. There was a significant improvement in adsorption properties of crosslinked PMA in the presence of Cs and HNT. The effect of synthesis parameters such as wt.% of Cs and HNT on swelling and process parameters such as solution pH, adsorbent dosage, contact time and feed concentration on adsorption of metal ions from water were studied in batch experiments. For a feed concentration of 100 mg/L of metal ion, an adsorbent dose of 0.25 g/L and a solution pH of 6, the Cs-PMA/HNT composite adsorbent containing 4 wt% Cs and 3 wt% HNT showed an adsorption capacity (mg/g)/removal% of 357.4/89.4 and 341.6/85.4 for single Pb(II) and Cd(II), respectively which reduced to 313.7/78.4 and 303.6/77.3 for the same metal ions in their binary mixtures in water.

    更新日期:2017-10-30
  • In situ controlled release of stromal cell-derived factor-1α and antimiR-138 for on-demand cranial bone regeneration
    Carbohydr. Polym. (IF 4.811) Pub Date : 2017-10-28
    Guangsheng Wu, Chao Feng, Jingjing Quan, Zhongshan Wang, Wei Wei, Shengqi Zang, Shuai Kang, Guangyan Hui, Xiguang Chen, Qintao Wang
    更新日期:2017-10-28
  • One-step coagulation to construct durable anti-fouling and antibacterial cellulose film exploiting Ag@AgCl nanoparticle- triggered photo-catalytic degradation
    Carbohydr. Polym. (IF 4.811) Pub Date : 2017-10-28
    Xiaomin Zhang, You Su, Shengpei Su, Jin Zhu

    An anti-fouling and antibacterial surface of cellulose film was obtained by one-step coagulation of the cellulose-LiCl/Dimethyl acetamide (DMAc) solution with AgNO3 and polyvinyl pyrrolidone (PVP). The AgCl nanocrystals were embedded on the surface of cellulose film with the assistance of PVP, and the Ag@AgCl was formed due to the partly decomposition of AgCl under the visible-light irradiation. Morphology and size of the Ag@AgCl in cellulose matrix could be regulated by changing the concentration of PVP. From a series of comparative tests, Ag@AgCl could be stably embedded on cellulose film at the concentration of 1 wt% PVP, and its photo-degradation efficiency could be still retained 89% after 5-cycle testing. Meanwhile, a dramatic reduction in viable bacteria was also observed within 120 min of exposure on this film, and when exposure time was 180 min, no active bacteria was observed.This work provided a simple pathway to construct the functional cellulose film which could be applied as packaging materials.

    更新日期:2017-10-28
  • Hyaluronan Hydrogels Modified by Glycinated Kraft Lignin: Morphology, Swelling, Viscoelastic Properties and Biocompatibility
    Carbohydr. Polym. (IF 4.811) Pub Date : 2017-10-27
    Lenka Musilová, Aleš Mráček, Adriana Kovalcik, Petr Smolka, Antonín Minařík, Petr Humpolíček, Robert Vícha, Petr Ponížil
    更新日期:2017-10-28
  • Protective effects of natural and partially degraded konjac glucomannan on Bifidobacteria against antibiotic damage
    Carbohydr. Polym. (IF 4.811) Pub Date : 2017-10-27
    Yu-Heng Mao, Ang-Xin Song, Zhong-Ping Yao, Jian-Yong Wu

    This study was to evaluate the protective effects of a dietary fiber, konjac glucomannan (KGM) from the plant tuber of Amorphohallus konjac on Bifidobacteria against antibiotic damage. KGM (∼8.8 × 108 Da) was partially degraded with high-intensity ultrasound to KGM-US (∼1.8 × 106 Da) and then hydrolyzed with trifluoroacetic acid (TFA) to KGM-AH (1369 Da). KGM-US (at 5 g/l) showed the most significant protective effect on most bifidobacterial strains against penicillin and streptomycin inhibition, increasing the minimal inhibitory and bactericidal concentration (MIC and MBC) dramatically, and KGM also showed significant effects on enhancing the MBC of enrofloxacin, penicillin, tetracycline and streptomycin. In addition, the adsorbance ability and biofilm improving effects of KGM and degraded KGM products may partially contributed to the protective effects. The results suggested that KGM and ultrasound treated KGM have protective effects for the human gut probiotic bacteria against the damage caused by specific antibiotics.

    更新日期:2017-10-28
  • Polysaccharide metallohydrogel obtained from Salecan and trivalent chromium: Synthesis and characterization
    Carbohydr. Polym. (IF 4.811) Pub Date : 2017-10-26
    Ting Su, Xiaoliang Qi, Gancheng Zuo, Xihao Pan, Jianfa Zhang, Zhiwei Han, Wei Dong
    更新日期:2017-10-27
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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