The Experts below are selected from a list of 324 Experts worldwide ranked by ideXlab platform
Desana Lišková - One of the best experts on this subject based on the ideXlab platform.
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Galactoglucomannan oligosaccharides alleviate cadmium stress in arabidopsis
Journal of Plant Physiology, 2014Co-Authors: Danica Kucerova, Karin Kollarova, Ivan Zelko, Zuzana Vatehova, Desana LiškováAbstract:Summary Our study focused on the mediatory role of Galactoglucomannan oligosaccharides (GGMOs) in plant protection against cadmium stress, examined mainly on the primary root growth of Arabidopsis thaliana . The application of GGMOs diminished the negative effect of cadmium on root length, root growth dynamics and also on photosynthetic pigment content. We tested the hypothesis that the effect of GGMOs is associated with decreased cadmium accumulation or its modified distribution. Cadmium distribution was observed chronologically from the first day of plant culture and depended on the duration of cadmium treatment. First, cadmium was stored in the root and hypocotyl and later transported by xylem to the leaves and stored there in trichomes. The protective effect of GGMOs was not based on modified cadmium distribution or its decreased accumulation. In cadmium and GGMOs + cadmium-treated plants, the formation of suberin lamellae was shifted closer to the root apex compared to the control and GGMOs. No significant changes between cadmium and GGMOs + cadmium variants in suberin lamellae development corresponded with any differences in cadmium uptake. GGMOs also stimulated Arabidopsis root growth under non-stress conditions. In this case, suberin lamellae were developed more distantly from the root apex in comparison with the control. Faster solute and water transport could explain the faster plant growth induced by GGMOs. Our results suggest that, in cadmium-stressed plants, GGMOs’ protective action is associated with the response at the metabolic level.
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Galactoglucomannan oligosaccharides are assumed to affect tracheary element formation via interaction with auxin in zinnia xylogenic cell culture
Plant Cell Reports, 2013Co-Authors: Anna Kakosova, Deborah Goffner, Catherine Digonnet, Desana LiškováAbstract:Key message Galactoglucomannan oligosaccharides seem to interact with auxin in xylogenic cell culture, thus influencing mainly metaxylem-like tracheary element differentiation depending on timing with hormones and the process kinetics.
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Galactoglucomannan oligosaccharides are assumed to affect tracheary element formation via interaction with auxin in zinnia xylogenic cell culture
Plant Cell Reports, 2013Co-Authors: Anna Kakosova, Deborah Goffner, Catherine Digonnet, Desana LiškováAbstract:Galactoglucomannan oligosaccharides seem to interact with auxin in xylogenic cell culture, thus influencing mainly metaxylem-like tracheary element differentiation depending on timing with hormones and the process kinetics. Complex mapping of Zinnia mesophyll cell transdifferentiation into tracheary elements with or without prior cell division was documented after palisade and spongy parenchyma cell immobilization during the first 4 days of culture. Here, we report a positive effect of Galactoglucomannan oligosaccharides on cell viability and density and higher metaxylem-like tracheary element formation in xylogenic cell culture. The maximal positive effect was achieved by the simultaneous addition of the oligosaccharides and growth hormones (auxin, cytokinin) to the cell culture medium. Moreover, a large number of metaxylem-like tracheary elements were observed in a low-auxin medium supplemented with oligosaccharides, but not in a low-cytokinin medium, suggesting a close relationship between auxin and the oligosaccharides during tracheary element formation.
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Galactoglucomannan oligosaccharides inhibition of elongation growth is in pea epicotyls coupled with peroxidase activity
Biologia, 2009Co-Authors: Karin Kollarova, ľudmila Slovakova, Edita Kollerova, Desana LiškováAbstract:The effect of Galactoglucomannan oligosaccharides — GGMOs, GGMOs-r (GGMOs with reduced reducing ends), and GGMOs-g (GGMOs with reduced number of d-galactose units) on peroxidase activity was determined in pea epicotyls. GGMOs didn’t significantly modify the activity of soluble peroxidases. However, cell wall-associated peroxidases activity increased after GGMOs and GGMOs-r treatment, while in the presence of GGMOs-g this activity was significantly lower. These results are inversely related to the GGMOs, GGMOs-r, and GGMOs-g effect on elongation growth induced by 2,4-D (2,4-dichlorophenoxyacetic acid) in pea epicotyls. It can be concluded that GGMOs evoked inhibition of the elongation growth induced by auxin is probably associated with cell wall modifications catalysed by peroxidase.
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Influence of Galactoglucomannan oligosaccharides on root culture of Karwinskia humboldtiana
Plant Cell Tissue and Organ Culture, 2007Co-Authors: Karin Kollarova, Desana LiškováAbstract:Galactoglucomannan oligosaccharides (GGMOs) activity in K . humboldtiana root culture has been determined. GGMOs inhibited adventitious root growth and lateral root induction in contrast to IAA, IBA, and NAA stimulating effect in these processes. Similarly, the combination of GGMOs with natural auxins (IAA, IBA) evoked an inhibition of adventitious root growth and lateral root induction that depended on the oligosaccharides concentration and the type of auxin. The growth stimulating effect of the synthetic auxin, NAA, in adventitious roots was negatively affected by GGMOs, but they were without influence on lateral root induction. The presence of oligosaccharides triggered lateral root position on adventitious roots and the anatomy of adventitious roots (diameter, proportion of primary cortex to the central cylinder, number and size of primary cortical cells, intercellular spaces, and the number of starch grains in cells of primary cortex) in dependence on their coactions with auxin.
Stefan Willför - One of the best experts on this subject based on the ideXlab platform.
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O-acetyl Galactoglucomannan esters for barrier coatings
Cellulose, 2014Co-Authors: Victor Kisonen, Chunlin Xu, Jonas Hartman, Roger Bollström, Hille Rautkoski, Maristiina Nurmi, Patrik Eklund, Jarl Hemming, Stefan WillförAbstract:A major enhancement of grease and water vapor barrier properties was accomplished with a 1–10 g/m^2 coating of O -acetyl Galactoglucomannan (GGM) ester or with GGM coatings applied as water dispersions on cartonboard. GGMs were esterified with phthalic and benzoic anhydrides, respectively. The novel phthalic esters of GGM (GGM-Ph) were characterized with HPLC, NMR, and matrix-assisted laser desorption/ionization with mass spectrometry (MALDI-TOF-MS). The degree of substitution of GGM-Ph was obtained by ^1H NMR, ^13C NMR, and HPLC. The GGM esters and GGM were coated onto cartonboard, and they demonstrated good moisture and very good grease resistance even with thin 1–3 g/m^2 coatings. The time for penetration of 0.1 % rapeseed oil was 54 h with the 2.4 g/m^2 coating thickness. The lowest water vapor transmission value was 39 g/m^2/24 h with 9.7 g/m^2 coating. The GGM esters had clearly higher water resistance and slightly higher grease barrier values than native GGM. High-molar-mass-based GGM (50 kg/mol) and GGM-Ph rendered better water vapor and grease barrier properties than low-molar-mass GGM (9 kg/mol) and GGM-Ph. The GGM-based coatings can be safely used on an industrial scale as water was used as a solvent. As obtained from non-food-based side-stream wood-based resources, GGM and GGM esters project a sustainable and modern conception for barrier purposes in food packaging.
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Modification of nanofibrillated cellulose using amphiphilic block-structured Galactoglucomannans
Carbohydrate Polymers, 2014Co-Authors: Alina Lozhechnikova, Chunlin Xu, Stefan Willför, Jari Vartiainen, Monika ÖsterbergAbstract:Nanofibrillated cellulose (NFC) and hemicelluloses have shown to be highly promising renewable components both as barrier materials and in novel biocomposites. However, the hydrophilic nature of these materials restricts their use in some applications. In this work, the usability of modified O-acetyl Galactoglucomannan (GGM) for modification of NFC surface properties was studied. Four GGM-block-structured, amphiphilic derivatives were synthesized using either fatty acids or polydimethylsiloxane as hydrophobic tails. The adsorption of these GGM derivatives was consecutively examined in aqueous solution using a quartz crystal microbalance with dissipation monitoring (QCM-D). It was found that the hydrophobic tails did not hinder adsorption of the GGM derivatives to cellulose, which was concluded to be due to the presence of the native GGM-block with high affinity to cellulose. The layer properties of the adsorbed block-co-polymers were discussed and evaluated. Self-standing NFC films were further prepared and coated with the GGM derivatives and the effect of the surface modification on wetting properties and oxygen permeability (OP) of the modified films was assessed.
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synthesis of novel cationic hydrogels from spruce o acetyl Galactoglucomannan for metal ion removal
247th National Spring Meeting of the American-Chemical-Society (ACS) MAR 16-20 2014 Dallas TX, 2014Co-Authors: Maria Soledad Chavez Bastidas, Chunlin Xu, Julio Antonio Sanchez Poblete, Regis Teixeira Mendonça, Stefan WillförAbstract:Synthesis of novel cationic hydrogels from spruce O-acetyl Galactoglucomannan for metal ion removal
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synthesis of set lrp induced Galactoglucomannan diblock copolymers
Journal of Polymer Science Part A, 2013Co-Authors: Chunlin Xu, Otto Langvik, Peter Backman, Jarl Hemming, Stefan WillförAbstract:Polysaccharides are biorenewable and biodegradable starting materials for the development of functional materials. The synthesis of a monofunctional macroinitiator for single electron transfer-livi ...
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Cationised O-acetyl Galactoglucomannans: synthesis and characterisation.
Carbohydrate Polymers, 2013Co-Authors: Victor Kisonen, Andrey Pranovich, Chunlin Xu, Hanna Lindqvist, Patrik Eklund, Anna Sundberg, Jari Sinkkonen, Francisco Vilaplana, Stefan WillförAbstract:Water-soluble O-acetyl-Galactoglucomannans (GGMs) can be obtained from Norway spruce by hot-water-extraction of the wood or as a side product by ultrafiltration of mechanical pulping waters. Cationic and amphiphilic polysaccharides and their derivatives are of interest for a number of applications and thus quaternary nitrogen moieties with cationic charge were grafted onto GGMs in the heterogeneous reaction to render a cationic polyelectrolyte. The degree of substitution was measured by elemental analysis of nitrogen, by quantitative 13C NMR and interestingly also by polyelectrolyte titration and the results were congruent. NMR, matrix-assisted laser desorption/ionisation mass spectroscopy (MALDI-TOF-MS), and FT-IR analysis were used to characterise the product. THF or DMSO with water enhanced the reaction efficiency and decreased Mw reduction in comparison to plain water as a reaction media. Cationised GGM was also successfully acetylated. The cationic derivatives of hemicelluloses can potentially be utilised as polyelectrolyte layers in packaging and pharmaceutical applications.
Chunlin Xu - One of the best experts on this subject based on the ideXlab platform.
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strong reinforcing effects from Galactoglucomannan hemicellulose on mechanical behavior of wet cellulose nanofiber gels
Journal of Materials Science, 2015Co-Authors: Kasinee Prakobna, Chunlin Xu, Victor Kisonen, Lars BerglundAbstract:Softwood hemicelluloses could potentially be combined with cellulose and used in packaging materials. In the present study, Galactoglucomannan (GGM) is adsorbed to wood cellulose nanofibers (CNF) and filtered and dried or hot-pressed to form nanocomposite films. The CNF/GGM fibril diameters are characterized by AFM, and the colloidal behavior by dynamic light scattering. Mechanical properties are measured in uniaxial tension for wet gels, dried films, and hot-pressed films. The role of GGM is particularly important for the wet gels. The wet gels of CNF/GGM exhibit remarkable improvement in mechanical properties. FE-SEM fractography and moisture sorption studies are carried out to interpret the results for hygromechanical properties. The present study shows that GGM may find use as a molecular scale cellulose binding agent, causing little sacrifice in mechanical properties and improving wet strength.
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strong effects from Galactoglucomannan hemicellulose on mechanical behavior of wet cellulose nanofiber gels
2015Co-Authors: Kasinee Prakobna, Chunlin Xu, Victor Kisonen, Lars BerglundAbstract:Strong effects from Galactoglucomannan hemicellulose on mechanical behavior of wet cellulose nanofiber gels
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O-acetyl Galactoglucomannan esters for barrier coatings
Cellulose, 2014Co-Authors: Victor Kisonen, Chunlin Xu, Jonas Hartman, Roger Bollström, Hille Rautkoski, Maristiina Nurmi, Patrik Eklund, Jarl Hemming, Stefan WillförAbstract:A major enhancement of grease and water vapor barrier properties was accomplished with a 1–10 g/m^2 coating of O -acetyl Galactoglucomannan (GGM) ester or with GGM coatings applied as water dispersions on cartonboard. GGMs were esterified with phthalic and benzoic anhydrides, respectively. The novel phthalic esters of GGM (GGM-Ph) were characterized with HPLC, NMR, and matrix-assisted laser desorption/ionization with mass spectrometry (MALDI-TOF-MS). The degree of substitution of GGM-Ph was obtained by ^1H NMR, ^13C NMR, and HPLC. The GGM esters and GGM were coated onto cartonboard, and they demonstrated good moisture and very good grease resistance even with thin 1–3 g/m^2 coatings. The time for penetration of 0.1 % rapeseed oil was 54 h with the 2.4 g/m^2 coating thickness. The lowest water vapor transmission value was 39 g/m^2/24 h with 9.7 g/m^2 coating. The GGM esters had clearly higher water resistance and slightly higher grease barrier values than native GGM. High-molar-mass-based GGM (50 kg/mol) and GGM-Ph rendered better water vapor and grease barrier properties than low-molar-mass GGM (9 kg/mol) and GGM-Ph. The GGM-based coatings can be safely used on an industrial scale as water was used as a solvent. As obtained from non-food-based side-stream wood-based resources, GGM and GGM esters project a sustainable and modern conception for barrier purposes in food packaging.
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Modification of nanofibrillated cellulose using amphiphilic block-structured Galactoglucomannans
Carbohydrate Polymers, 2014Co-Authors: Alina Lozhechnikova, Chunlin Xu, Stefan Willför, Jari Vartiainen, Monika ÖsterbergAbstract:Nanofibrillated cellulose (NFC) and hemicelluloses have shown to be highly promising renewable components both as barrier materials and in novel biocomposites. However, the hydrophilic nature of these materials restricts their use in some applications. In this work, the usability of modified O-acetyl Galactoglucomannan (GGM) for modification of NFC surface properties was studied. Four GGM-block-structured, amphiphilic derivatives were synthesized using either fatty acids or polydimethylsiloxane as hydrophobic tails. The adsorption of these GGM derivatives was consecutively examined in aqueous solution using a quartz crystal microbalance with dissipation monitoring (QCM-D). It was found that the hydrophobic tails did not hinder adsorption of the GGM derivatives to cellulose, which was concluded to be due to the presence of the native GGM-block with high affinity to cellulose. The layer properties of the adsorbed block-co-polymers were discussed and evaluated. Self-standing NFC films were further prepared and coated with the GGM derivatives and the effect of the surface modification on wetting properties and oxygen permeability (OP) of the modified films was assessed.
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synthesis of novel cationic hydrogels from spruce o acetyl Galactoglucomannan for metal ion removal
247th National Spring Meeting of the American-Chemical-Society (ACS) MAR 16-20 2014 Dallas TX, 2014Co-Authors: Maria Soledad Chavez Bastidas, Chunlin Xu, Julio Antonio Sanchez Poblete, Regis Teixeira Mendonça, Stefan WillförAbstract:Synthesis of novel cationic hydrogels from spruce O-acetyl Galactoglucomannan for metal ion removal
Bjarne Holmbom - One of the best experts on this subject based on the ideXlab platform.
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Galactoglucomannan derivatives and their application in papermaking
Bioresources, 2013Co-Authors: Hanna Lindqvist, Jessica Holmback, Ari Rosling, Kristian Salminen, Markku Auer, Bjarne Holmbom, Anna SundbergAbstract:Native Galactoglucomannans (GGMs), which were isolated from thermomechanical pulping waters of Norway spruce, were modified through cationization, carboxymethylation, and imination at the reducing end with a primary long-chain hydrocarbon amine. The derivatives were tested for their papermaking properties. The native GGMs increased the wet tensile strength as a result of the dispersion of fibrils in the wet fibre web. In wood-containing paper, GGMs increased the retention of fines and extractives without a decrease in paper strength. The GGMs also flocculated fillers effectively. The cationic GGMs were able to interact between fibrous fine material and fibres, as well as with fillers. Therefore, an electrostatic mechanism of action is suggested. Carboxymethylated GGMs are believed to bind to fibres and fines through divalent metal ions present in wood. For the amphiphilic amine-modified GGMs, the alkane chain attached to the reducing end appeared to play a key role. The tail was orientated towards the hydrophobic particles; the resulting paper was the most hydrophilic, since the hydrophobic particles were covered with the polysaccharide. Based on the present results, it can be concluded that Galactoglucomannans can be modified to yield new and interesting functionalities to wet-end additives for papermaking and other purposes.
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acid hydrolysis of o acetyl Galactoglucomannan
Catalysis Science & Technology, 2013Co-Authors: Bright T Kusema, Tea Tonnov, Paivi Makiarvela, Stefan Willför, Bjarne Holmbom, Tapio Salmi, Dmitry Yu. MurzinAbstract:Acid hydrolysis of O-acetyl-Galactoglucomannan (GGM), the main non-cellulosic polysaccharide in coniferous wood, was studied at 90 °C in the pH range of 0.5–2.0 using different acids (hydrochloric acid, sulfuric acid, trifluoroacetic acid, oxalic acid, and formic acid) as homogeneous catalysts and cation exchange resins (Smopex 101 and Amberlyst 15) as heterogeneous catalysts. The hydrolysis rate was exclusively dependent on the pH of the solution, but independent of the concentration and type of acid. Analysis of the formation rates of oligomers with DP 2–5 revealed that GGM hydrolysis occurs rather randomly. The final products were mannose, galactose, and glucose. In the beginning of the reaction, the formation of galactose was slightly faster than those of other sugars, since galactose is a side substituent to the glucose–mannose main chain of GGM. However, with longer reaction times, the formation rates of sugar monomers were correlated with their initial abundances in the polysaccharide. Autocatalytic kinetics was observed in the presence of the heterogeneous catalysts: an induction time was observed, after which the reaction proceeded with the same rates as with homogeneous acids. The autocatalytic effect is probably explained by the increase of the hydrolysis rate constant, as the GGM chain length decreases and the molecule becomes more accessible for the active sites on the outer surface of the catalyst.
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Galactoglucomannan extracted from spruce picea abies as a carbohydrate source for probiotic bacteria
Journal of Agricultural and Food Chemistry, 2012Co-Authors: Lauri Polari, Pauliina Ojansivu, Christer Eckerman, Sari Makela, Bjarne Holmbom, Seppo SalminenAbstract:A prebiotic is a nonviable food component that confers a health benefit on the host associated with modulation of the microbiota. Hemicelluloses are the second most common group of polysaccharides in nature and they occur in plant cell walls. The predominant hemicellulose in softwood species is Galactoglucomannan, and based on its chemical structure and information available about similar saccharides, Galactoglucomannan may be postulated to have prebiotic properties. In this study we demonstrated that Bifidobacterium species are able to ferment hemicellulose-derived saccharides. Significant stimulatory effects on the growth rates of bifidobacteria were found when Galactoglucomannan or its hydrolysis products were present. Bifidobacterium animalis subsp. lactis strain Bb12, a commonly used probiotic, was able to adapt to the Galactoglucomannan leading to more efficient utilization of hemicellulose-derived saccharides. Our study demonstrates prebiotic properties for Galactoglucomannan and warrants the next ...
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Rheological properties of water-soluble spruce O-acetyl Galactoglucomannans
Carbohydrate Polymers, 2009Co-Authors: Chunlin Xu, Peter Holmlund, Stefan Willför, Bjarne HolmbomAbstract:Abstract The thermal and rheological properties of spray-dried, ethanol-precipitated, purified, and deacetylated spruce Galactoglucomannans (GGM) were investigated by rheological measurements and differential scanning calorimetry. The shear rate dependence of viscosity and the effects of the drying method, temperature, ionic strength, and deacetylation on rheological properties were studied. GGM solutions exhibited a shear thinning behaviour. GGM solutions did not obey the Cox–Merz rule. The storage modulus of GGM solutions increased with an increase in concentration; gradually until a concentration of 5%, but rapidly at higher concentrations. Ethanol-precipitated GGM solutions showed a more elastic behaviour than spray-dried GGM solutions. Deacetylation caused an increase in apparent viscosity and more significantly in storage modulus. The storage modulus increased slightly with a decrease in temperature. A small amount addition of NaCl slightly changed the oscillatory behaviour. The effects of above factors were discussed in terms of molecular interactions. The rheological measurements of GGM solutions provide the basis of functionalities of GGM solutions.
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Hydrolytic stability of water-soluble spruce O-acetyl Galactoglucomannans
Holzforschung, 2009Co-Authors: Chunlin Xu, Andrey Pranovich, J. Hemmimg, Simone Albrecht, Hendrik Arie Schols, Bjarne Holmbom, Stefan WillförAbstract:Water-soluble native O-acetyl Galactoglucomannan (GGM) from spruce is a polysaccharide that can be produced in an industrial scale. To develop GGM applications, information is needed on its stability, particularly under acidic conditions. Therefore, acid hydrolysis of spruce GGM was investigated at various pH levels and temperatures. The results allow an estimation of the stability of GGM under food processing conditions and in biological systems. Determination of the average molar mass demonstrated that spruce GGM was stable at pH 1 and 37°C, as well as at pH 3 and 70°C. GGM was hydrolysed at pH 1 and 90°C. GGM oligomers and monomers were detected after degradation. Some of the oligomers contained O-acetyl groups. Monosaccharides were the predominant products in the hydrolysates after treatment at pH 1 and 90°C for 48 h. Pentoses, present in GGM samples as impurities, were released more easily than GGM hexoses. Glucose was more difficult to release than mannose. Traces of 6-deoxy-mannose and levoglucosan were found in the hydrolysates, indicating further degradation of hydrolysed monosaccharides.
Victor Kisonen - One of the best experts on this subject based on the ideXlab platform.
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strong reinforcing effects from Galactoglucomannan hemicellulose on mechanical behavior of wet cellulose nanofiber gels
Journal of Materials Science, 2015Co-Authors: Kasinee Prakobna, Chunlin Xu, Victor Kisonen, Lars BerglundAbstract:Softwood hemicelluloses could potentially be combined with cellulose and used in packaging materials. In the present study, Galactoglucomannan (GGM) is adsorbed to wood cellulose nanofibers (CNF) and filtered and dried or hot-pressed to form nanocomposite films. The CNF/GGM fibril diameters are characterized by AFM, and the colloidal behavior by dynamic light scattering. Mechanical properties are measured in uniaxial tension for wet gels, dried films, and hot-pressed films. The role of GGM is particularly important for the wet gels. The wet gels of CNF/GGM exhibit remarkable improvement in mechanical properties. FE-SEM fractography and moisture sorption studies are carried out to interpret the results for hygromechanical properties. The present study shows that GGM may find use as a molecular scale cellulose binding agent, causing little sacrifice in mechanical properties and improving wet strength.
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strong effects from Galactoglucomannan hemicellulose on mechanical behavior of wet cellulose nanofiber gels
2015Co-Authors: Kasinee Prakobna, Chunlin Xu, Victor Kisonen, Lars BerglundAbstract:Strong effects from Galactoglucomannan hemicellulose on mechanical behavior of wet cellulose nanofiber gels
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O-acetyl Galactoglucomannan esters for barrier coatings
Cellulose, 2014Co-Authors: Victor Kisonen, Chunlin Xu, Jonas Hartman, Roger Bollström, Hille Rautkoski, Maristiina Nurmi, Patrik Eklund, Jarl Hemming, Stefan WillförAbstract:A major enhancement of grease and water vapor barrier properties was accomplished with a 1–10 g/m^2 coating of O -acetyl Galactoglucomannan (GGM) ester or with GGM coatings applied as water dispersions on cartonboard. GGMs were esterified with phthalic and benzoic anhydrides, respectively. The novel phthalic esters of GGM (GGM-Ph) were characterized with HPLC, NMR, and matrix-assisted laser desorption/ionization with mass spectrometry (MALDI-TOF-MS). The degree of substitution of GGM-Ph was obtained by ^1H NMR, ^13C NMR, and HPLC. The GGM esters and GGM were coated onto cartonboard, and they demonstrated good moisture and very good grease resistance even with thin 1–3 g/m^2 coatings. The time for penetration of 0.1 % rapeseed oil was 54 h with the 2.4 g/m^2 coating thickness. The lowest water vapor transmission value was 39 g/m^2/24 h with 9.7 g/m^2 coating. The GGM esters had clearly higher water resistance and slightly higher grease barrier values than native GGM. High-molar-mass-based GGM (50 kg/mol) and GGM-Ph rendered better water vapor and grease barrier properties than low-molar-mass GGM (9 kg/mol) and GGM-Ph. The GGM-based coatings can be safely used on an industrial scale as water was used as a solvent. As obtained from non-food-based side-stream wood-based resources, GGM and GGM esters project a sustainable and modern conception for barrier purposes in food packaging.
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Cationised O-acetyl Galactoglucomannans: synthesis and characterisation.
Carbohydrate Polymers, 2013Co-Authors: Victor Kisonen, Andrey Pranovich, Chunlin Xu, Hanna Lindqvist, Patrik Eklund, Anna Sundberg, Jari Sinkkonen, Francisco Vilaplana, Stefan WillförAbstract:Water-soluble O-acetyl-Galactoglucomannans (GGMs) can be obtained from Norway spruce by hot-water-extraction of the wood or as a side product by ultrafiltration of mechanical pulping waters. Cationic and amphiphilic polysaccharides and their derivatives are of interest for a number of applications and thus quaternary nitrogen moieties with cationic charge were grafted onto GGMs in the heterogeneous reaction to render a cationic polyelectrolyte. The degree of substitution was measured by elemental analysis of nitrogen, by quantitative 13C NMR and interestingly also by polyelectrolyte titration and the results were congruent. NMR, matrix-assisted laser desorption/ionisation mass spectroscopy (MALDI-TOF-MS), and FT-IR analysis were used to characterise the product. THF or DMSO with water enhanced the reaction efficiency and decreased Mw reduction in comparison to plain water as a reaction media. Cationised GGM was also successfully acetylated. The cationic derivatives of hemicelluloses can potentially be utilised as polyelectrolyte layers in packaging and pharmaceutical applications.
