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Commercial fructans (inulin and oligofructose) are generally obtained from crops such as chicory, Jerusalem artichoke or agave. However, there are agricultural by-products, namely asparagus roots, which could be considered potential sources of fructans. In this work, the fructans extracted from asparagus roots and three commercial ones from chicory and agave were studied in order to compare their composition, physicochemical characteristics, and potential health effects. Asparagus fructans had similar chemical composition to the others, especially in moisture, simple sugars and total fructan contents. However, its contents of ash, protein and phenolic compounds were higher. FTIR analysis confirmed these differences in composition. Orafti®GR showed the highest degree of polymerization (DP) of up to 40, with asparagus fructans (up to 25) falling between Orafti®GR and the others (DP 10-11). Although asparagus fructan powder had a lower fructan content and lower DP than Orafti®GR, its viscosity was higher, probably due to the presence of proteins. The existence of phenolic compounds lent antioxidant activity to asparagus fructans. The prebiotic activity in vitro of the four samples was similar and, in preliminary assays, asparagus fructan extract presented health effects related to infertility and diabetes diseases. All these characteristics confer a great potential for asparagus fructans to be included in the prebiotics market.

Cellulose ethers are now of great practical importance. The advantages of cellulose ethers include: resistance to chemical reagents, water resistance, frost resistance, lightfastness, low flammability, the ability to dissolve in common organic solvents, good film-forming and thermoplastic properties, etc. Some cellulose ethers with a certain degree of substitution can dissolve not only in organic solvents, but also in dilute aqueous solutions of alkalis and even in cold water, which is of great importance for their practical application

Since cellulose is a polycyclic high molecular weight compound that contains many polar hydroxyl groups, its macromolecular chain is not flexible, it is tightly packed because the macromolecule is highly ordered. From this it can be concluded that cellulose is soluble only in some solvents, but not in various solvents

Cellulose ethers are now of great practical importance. The advantages of cellulose ethers include: resistance to chemical reagents, water resistance, frost resistance, lightfastness, low flammability, the ability to dissolve in common organic solvents, good film-forming and thermoplastic properties, etc. Some cellulose ethers with a certain degree of substitution can dissolve not only in organic solvents, but also in dilute aqueous solutions of alkalis and even in cold water, which is of great importance for their practical application

Paulownia wood pulp, shredded pulp waste and waste paper were ground in a laboratory on a centrifugal mill to produce composite paper pulp. In laboratory conditions, samples of various paper casts and their compositions were obtained

Paulownia wood pulp, shredded pulp waste and waste paper were ground in a laboratory on a centrifugal mill to produce composite paper pulp. In laboratory conditions, samples of various paper casts and their compositions were obtained

Cellulose ethers are now of great practical importance. The advantages of cellulose ethers include: resistance to chemical reagents, water resistance, frost resistance, lightfastness, low flammability, the ability to dissolve in common organic solvents, good film-forming and thermoplastic properties, etc. Some cellulose ethers with a certain degree of substitution can dissolve not only in organic solvents, but also in dilute aqueous solutions of alkalis and even in cold water, which is of great importance for their practical application

Paulownia wood pulp, shredded pulp waste and waste paper were ground in a laboratory on a centrifugal mill to produce composite paper pulp. In laboratory conditions, samples of various paper casts and their compositions were obtained

Cellulose ethers are now of great practical importance. The advantages of cellulose ethers include: resistance to chemical reagents, water resistance, frost resistance, lightfastness, low flammability, the ability to dissolve in common organic solvents, good film-forming and thermoplastic properties, etc. Some cellulose ethers with a certain degree of substitution can dissolve not only in organic solvents, but also in dilute aqueous solutions of alkalis and even in cold water, which is of great importance for their practical application

Paulownia wood pulp, shredded pulp waste and waste paper were ground in a laboratory on a centrifugal mill to produce composite paper pulp. In laboratory conditions, samples of various paper casts and their compositions were obtained

Cellulose ethers are now of great practical importance. The advantages of cellulose ethers include: resistance to chemical reagents, water resistance, frost resistance, lightfastness, low flammability, the ability to dissolve in common organic solvents, good film-forming and thermoplastic properties, etc. Some cellulose ethers with a certain degree of substitution can dissolve not only in organic solvents, but also in dilute aqueous solutions of alkalis and even in cold water, which is of great importance for their practical application

Paulownia wood pulp, shredded pulp waste and waste paper were ground in a laboratory on a centrifugal mill to produce composite paper pulp. In laboratory conditions, samples of various paper casts and their compositions were obtained

Cellulose ethers are now of great practical importance. The advantages of cellulose ethers include: resistance to chemical reagents, water resistance, frost resistance, lightfastness, low flammability, the ability to dissolve in common organic solvents, good film-forming and thermoplastic properties, etc. Some cellulose ethers with a certain degree of substitution can dissolve not only in organic solvents, but also in dilute aqueous solutions of alkalis and even in cold water, which is of great importance for their practical application

Since cellulose is a polycyclic high molecular weight compound that contains many polar hydroxyl groups, its macromolecular chain is not flexible, it is tightly packed because the macromolecule is highly ordered. From this it can be concluded that cellulose is soluble only in some solvents, but not in various solvents

Paulownia wood pulp, shredded pulp waste and waste paper were ground in a laboratory on a centrifugal mill to produce composite paper pulp. In laboratory conditions, samples of various paper casts and their compositions were obtained

Cellulose ethers are now of great practical importance. The advantages of cellulose ethers include: resistance to chemical reagents, water resistance, frost resistance, lightfastness, low flammability, the ability to dissolve in common organic solvents, good film-forming and thermoplastic properties, etc. Some cellulose ethers with a certain degree of substitution can dissolve not only in organic solvents, but also in dilute aqueous solutions of alkalis and even in cold water, which is of great importance for their practical application

Since cellulose is a polycyclic high molecular weight compound that contains many polar hydroxyl groups, its macromolecular chain is not flexible, it is tightly packed because the macromolecule is highly ordered. From this it can be concluded that cellulose is soluble only in some solvents, but not in various solvents

Paulownia wood pulp, shredded pulp waste and waste paper were ground in a laboratory on a centrifugal mill to produce composite paper pulp. In laboratory conditions, samples of various paper casts and their compositions were obtained

Cellulose ethers are now of great practical importance. The advantages of cellulose ethers include: resistance to chemical reagents, water resistance, frost resistance, lightfastness, low flammability, the ability to dissolve in common organic solvents, good film-forming and thermoplastic properties, etc. Some cellulose ethers with a certain degree of substitution can dissolve not only in organic solvents, but also in dilute aqueous solutions of alkalis and even in cold water, which is of great importance for their practical application

The effects of iron oxide on the viscosity of the CaO-Al2O3-FetO-SiO2-MgO system Ruhrstahl-Heraeus (RH) refining slags with different CaO/Al2O3 ratios (C/A = 1.0 to 2.0) and various iron oxide contents (T.Fe = 4 to 18 wt%) were investigated. Iron oxide generally decreases the viscosity of the slags. In the relatively low iron oxide content region (i.e., T.Fe < 10 wt%), the increase in the C/A ratio decreases the viscosity of the slags, whereas it has less significant effect on the modification of the aluminate structure in the relatively high iron oxide content region. The addition of iron oxide to the slags with C/A < 1.3 effectively breaks the aluminate networks, while the network structure is less affected by the iron oxide in the slags with C/A 1.6. From the semi -quantitative analysis of Raman scattering data, the addition of iron oxide into the relatively acidic slags (C/A s 1.3) modifies the aluminate networks, which means that the [FeO4]-tetrahedra substitute for the [AlO4] -tetrahedra. Thus, the degree of polymerization of the melts decreases with increasing content of iron oxides. However, the effect of iron oxides is less significant in the relatively basic compositions (C/A 1.6). The activation energy for the viscous flow of the slags has a good linear correlation with the fraction of polymerized aluminate species, i.e., In OA,. However, the network-modifying role of iron oxide is limited within a critical concentration, which is also dependent on the C/A ratio of the CaO-Al2O3-FetO-SiO2-MgO slags., QC 20210503

Cellulose is the most abundant component of biomass and the one that requires the most activation energy (Ea) for pyrolysis. In this study, the dependence of Ea on the intrinsic cellulose characteristics, such as the degree of polymerization (DP), crystallinity, and crystal size, was studied in different cellulose samples, including samples from Eucalyptus globulus, Ulmus minor, Linun usitatissimum, Olea europaea, Robinia pseudoacacia, and Populus alba. Then, to describe the pyrolytic degradation of cellulose, the Ozawa-Flynn-Wall kinetic method was the most appropriate among the isoconversional models studied. An acceptable quadratic relationship of R-2 > 0.9 between the Ea values of the different cellulose samples with their corresponding DP, crystallinity index, and crystal size values was found. Therefore, low crystallinity and low-to-medium crystal size values are desired to obtain lower Ea values for cellulose pyrolysis. On the other hand, DP did not present a clear effect on Ea in the studied DP range. Keywords

С помощью математического планирования эксперимента разработаны оптимальные условия получения порошковой целлюлозы из беленой хвойной сульфатной целлюлозы, предназначенной для бумажного производства. По разработанным условиям получена порошковая целлюлоза для пищевой промышленности. По аналогичным условиям получен целлюлозный порошок из беленой лиственной сульфатной целлюлозы. Проведен сравнительный анализ свойств и структуры полученных образцов порошковой целлюлозы., With the help of the experiment planned mathematically, optimal conditions for the production of powdered pulp from bleached softwood sulphate pulp for papermaking were developed. According to the developed conditions powered cellulose for the food industry was obtained. Under similar conditions, pulp powder from bleached hardwood sulphate pulp was obtained. A comparative analysis of the properties and structure of the obtained samples of powdered cellulose was carried out.

This study provides insight into the thermal degradation of cotton cellulose nanocrystals (CNCs) by tuning their physico-chemical properties through acid hydrolysis using blends of phosphoric and sulfuric acid. CNCs isolated by sulfuric acid hydrolysis are known to degrade at lower temperatures than CNCs hydrolyzed with phosphoric acid; however, the reason for this change is unclear. Although all CNCs are inherently relatively thermally stable, their application in polymer composites and liquid formulations designed to function at high temperatures could be extended if thermal stability was improved. Herein, thermogravimetric analysis was carried out on six types of CNCs (in both acid and sodium form) with different surface chemistry, surface charge density, dimensions, crystallinity and degree of polymerization (DP) to identify the key properties that influence thermal stability of nanocellulose. In acid form, CNC surface charge density was found to be the determining factor in thermal stability due to de-esterification and acid-catalyzed degradation. Conversely, in sodium form, surface chemistry and charge density had a negligible effect on the onset of thermal degradation, however, the DP of the cellulose polymer chains highly influenced stability. The presence of more reducing ends in lower DP nanocrystals is inferred to facilitate thermally-induced depolymerization and degradation. Degree of crystallinity did not significantly affect CNC thermal stability. Studying CNCs produced from single or blends of acids (and changing the counterion) elucidated the thermal behavior of cellulose and furthermore demonstrated new routes to tailor CNCs thermal and colloidal stability. Graphical abstract: [Figure not available: see fulltext.]., QC 20190405

The paper presents the results of a comparative study on accelerated aging of specially designed experimental transformers and their corresponding laboratory models. The experimental transformers are 300 kVA, with insulation in line with medium size and large mineral oil immersed power transformers, having different initial water contents in the standard Kraft paper insulation of ca. 1 and 4 %. These transformers were subjected to the rated current and voltage conditions, operating in the irregular parallel operation, whereby the temperature of windings were measured with fiber optics sensors and kept at 105 C for 460 days. Each transformer was equipped with a removable tank which allowed access to the outer surface of the HV windings. Laboratory experiments were simulating experimental transformers and were performed in Erlenmeyer flasks, containing oil, paper materials, copper and iron in the same proportions as in the active part of the experimental transformers. The parameters that were monitored during aging were the following: degree of polymerization of paper, hot-spot temperature of transformers, water content in paper, and water and furans content in the oil. Estimations of water content in solid insulation of experimental transformers using frequency domain spectroscopy and the Perrier-Lukic moisture equilibrium chart were performed. The experimental results show that shortening of the insulation life, defined by the value of degree of polymerization, increased 2.5 times with increasing moisture content in the cellulose from ca. 1 to 4 %. For both experimental transformers and laboratory models, the relationships between the paper degree of polymerization and the furans content for dry and wet insulation was developed and is presented in the paper.

The paper presents the results of a comparative study on accelerated aging of specially designed experimental transformers and their corresponding laboratory models. The experimental transformers are 300 kVA, with insulation in line with medium size and large mineral oil immersed power transformers, having different initial water contents in the standard Kraft paper insulation of ca. 1 and 4 %. These transformers were subjected to the rated current and voltage conditions, operating in the irregular parallel operation, whereby the temperature of windings were measured with fiber optics sensors and kept at 105 C for 460 days. Each transformer was equipped with a removable tank which allowed access to the outer surface of the HV windings. Laboratory experiments were simulating experimental transformers and were performed in Erlenmeyer flasks, containing oil, paper materials, copper and iron in the same proportions as in the active part of the experimental transformers. The parameters that were monitored during aging were the following: degree of polymerization of paper, hot-spot temperature of transformers, water content in paper, and water and furans content in the oil. Estimations of water content in solid insulation of experimental transformers using frequency domain spectroscopy and the Perrier-Lukic moisture equilibrium chart were performed. The experimental results show that shortening of the insulation life, defined by the value of degree of polymerization, increased 2.5 times with increasing moisture content in the cellulose from ca. 1 to 4 %. For both experimental transformers and laboratory models, the relationships between the paper degree of polymerization and the furans content for dry and wet insulation was developed and is presented in the paper.

The frequently studied polysaccharide, chitosan oligosaccharide/chitooligosaccharide (COS) is the major degradation product of chitosan/chitin via chemical hydrolysis or enzymatic degradation involving deacetylation and depolymerization processes. Innumerable studies have revealed in the recent decade that COS has various promising biomedical implications in the past analysis, current developments and potential applications in a biomedical, pharmaceutical and agricultural sector. Innovations into COS derivatization has broadened its application in cosmeceutical and nutraceutical productions as well as in water treatment and environmental safety. In relation to its parent biomaterials and other available polysaccharides, COS has low molecular weight (Mw), higher degree of deacetylation (DD), higher degree of polymerization (DP), less viscous and complete water solubility, which endowed it with significant biological properties like antimicrobial, antioxidant, anti-inflammatory and antihypertensive, as well as drug/DNA delivery ability. In addition, it is also revealed to exhibit antidiabetic, anti-obesity, anti-HIV-1, anti-Alzheimer's disease, hypocholesterolemic, calcium absorption and hemostatic effects. Furthermore, COS is shown to have higher cellular transduction and completely absorbable via intestinal epithelium due to its cationic sphere exposed on the more exposed shorter N-glucosamine (N-Glc) units. This paper narrates the recent developments in COS biomedical applications while paying considerable attention to its physicochemical properties and its chemical composition. Its pharmacokinetic aspects are also briefly discussed while highlighting potential overdose or lethal dosing. In addition, due to its multiple NGlc unit composition and vulnerability to degradation, its safety is given significant attention. Finally, a suggestion is made for extensive study on COS anti-HIV effects with well-refined batches.

Steam explosion (150 – 200 ºC, 5 – 30 min) was performed on a commercial cellulose presented in two configurations (fiberized and compact sheet) and its effect on their chemical and physical properties was studied, along with the influence of two different preservation methods (acetone drying and freezing) after pretreatment. No degradation compounds were produced during pretreatment, although solid recovery (RS) decreased with temperature from 90% to 62%. Similar particle size and surface conditions (increased porosity) were found for both types of pretreated samples despite the extremely different initial configuration. Crystallinity diminished for 150 ºC samples, but 200 ºC pretreatment promoted recrystallization. Pretreatment also reduced polymerization degree, although enzymatic accessibility did not improve. Both acetone and freezing processes extremely affected cellulose properties. Acetone drying counterbalanced crystallinity and enzymatic accessibility variations of pretreated samples, while decreasing polymerization degree to 302. Freezing dramatically decreased enzymatic accessibility of pretreated samples down to 15.8%., UIC-Consejería de Educación Junta de Castilla y León, University of Valladolid

Pectins are the most complex polysaccharides of the plant cell wall. Based on the number of methylations, acetylations, and glycosidic linkages present in their structures, it is estimated that up to 67 transferase activities are involved in pectin biosynthesis. Pectic galactans constitute a major part of pectin in the form of side chains of rhamnogalacturonan-I. In Arabidopsis, Galactan Synthase 1 (GALS1) catalyzes the addition of galactose units from UDP-Gal to growing β-1,4-galactan chains. However, the mechanisms for obtaining varying degrees of polymerization remain poorly understood. In this study, we show that AtGALS1 is bifunctional, catalyzing both the transfer of galactose from UDP-α-d-Gal and the transfer of an arabinopyranose from UDP-β-l-Arap to galactan chains. The two substrates share a similar structure, but UDP-α-d-Gal is the preferred substrate, with a tenfold higher affinity. Transfer of Arap to galactan prevents further addition of galactose residues, resulting in a lower degree of polymerization. We show that this dual activity occurs both in vitro and in vivo. The herein described bi-functionality of AtGALS1 may suggest that plants can produce the incredible structural diversity of polysaccharides without a dedicated glycosyltransferase for each glycosidic linkage. This article is protected by copyright. All rights reserved.

It is shown that from wood coniferous sawdust it is possible to obtain powder cellulose using the following stages: delignification (cooking) of the initial wood raw materials, hydrolysis of nitric acid by the obtained technical cellulose with the formation of powder, bleaching with a solution of hydrogen peroxide of powder cellulose., Показано, что из древесных хвойных опилок можно получить порошковую целлюлозу с использованием следующих стадий: делигнификации (варки) исходного древесного сырья, гидролиза азотной кислотой полученной технической целлюлозы с образованием порошка, отбелки раствором пероксида водорода порошковой целлюлозы.

Steam explosion (150 – 200 ºC, 5 – 30 min) was performed on a commercial cellulose presented in two configurations (fiberized and compact sheet) and its effect on their chemical and physical properties was studied, along with the influence of two different preservation methods (acetone drying and freezing) after pretreatment. No degradation compounds were produced during pretreatment, although solid recovery (RS) decreased with temperature from 90% to 62%. Similar particle size and surface conditions (increased porosity) were found for both types of pretreated samples despite the extremely different initial configuration. Crystallinity diminished for 150 ºC samples, but 200 ºC pretreatment promoted recrystallization. Pretreatment also reduced polymerization degree, although enzymatic accessibility did not improve. Both acetone and freezing processes extremely affected cellulose properties. Acetone drying counterbalanced crystallinity and enzymatic accessibility variations of pretreated samples, while decreasing polymerization degree to 302. Freezing dramatically decreased enzymatic accessibility of pretreated samples down to 15.8%., UIC-Consejería de Educación Junta de Castilla y León, University of Valladolid

Steam explosion (150 – 200 ºC, 5 – 30 min) was performed on a commercial cellulose presented in two configurations (fiberized and compact sheet) and its effect on their chemical and physical properties was studied, along with the influence of two different preservation methods (acetone drying and freezing) after pretreatment. No degradation compounds were produced during pretreatment, although solid recovery (RS) decreased with temperature from 90% to 62%. Similar particle size and surface conditions (increased porosity) were found for both types of pretreated samples despite the extremely different initial configuration. Crystallinity diminished for 150 ºC samples, but 200 ºC pretreatment promoted recrystallization. Pretreatment also reduced polymerization degree, although enzymatic accessibility did not improve. Both acetone and freezing processes extremely affected cellulose properties. Acetone drying counterbalanced crystallinity and enzymatic accessibility variations of pretreated samples, while decreasing polymerization degree to 302. Freezing dramatically decreased enzymatic accessibility of pretreated samples down to 15.8%., UIC-Consejería de Educación Junta de Castilla y León, University of Valladolid

Steam explosion (150 – 200 ºC, 5 – 30 min) was performed on a commercial cellulose presented in two configurations (fiberized and compact sheet) and its effect on their chemical and physical properties was studied, along with the influence of two different preservation methods (acetone drying and freezing) after pretreatment. No degradation compounds were produced during pretreatment, although solid recovery (RS) decreased with temperature from 90% to 62%. Similar particle size and surface conditions (increased porosity) were found for both types of pretreated samples despite the extremely different initial configuration. Crystallinity diminished for 150 ºC samples, but 200 ºC pretreatment promoted recrystallization. Pretreatment also reduced polymerization degree, although enzymatic accessibility did not improve. Both acetone and freezing processes extremely affected cellulose properties. Acetone drying counterbalanced crystallinity and enzymatic accessibility variations of pretreated samples, while decreasing polymerization degree to 302. Freezing dramatically decreased enzymatic accessibility of pretreated samples down to 15.8%., UIC-Consejería de Educación Junta de Castilla y León, University of Valladolid

The viscosity of low SiO2 (10–20 mass%)-CaO-Al2O3 slag system was measured in a wide temperature range (1 623–2 800 K) using the rotational bob method and the aerodynamic levitation method. The influence of SiO2/Al2O3 ratio and CaO/Al2O3 ratio on the viscosity was examined. It was concluded that the SiO2/Al2O3 ratio did not affect the degree of polymerization of the aluminosilicate network in the composition range of the present study. An abnormal behaviour of the viscosity was observed at a CaO/Al2O3 ratio of 1.57 which was attributed to the formation of 12CaO·7Al2O3-like clusters. It was concluded that the overall influence on the viscosity could be expressed as the summation of the influence from the aluminosilicate network and the influence from the cluster formation of the primary precipitating solid phase. The temperature dependence of the cluster formation was coupled to the driving force of precipitation of the 12CaO·7Al2O3 phase.

Aging of a power transformer’s insulation system produces carboxylic acids. These acids—acetic, formic and levulinic—are absorbed by the paper insulating material, thus accelerating the degradation of the whole insulation system. In this contribution, the effect of these acids on the aging of oil-impregnated paper insulation used in power transformer is reported. A laboratory aging experiment considering different concentrations of these three acids was performed to assess their effect on the insulation system’s degradation. Each acid was individually mixed with virgin oil, and a mixture of acids was also blended with oil. The paper’s degradation was assessed by the degree of polymerization (DPv). It was found that the DPv of paper aged with formic acid decreased much faster in comparison to the other acids

Cílem této disertační práce bylo vybělit natronovou buničinu ze slámy řepky olejky. První část této disertační práce je zaměřena na uvaření natronové buničiny ze slámy řepky olejky na požadovaný stupeň delignifikace. V druhé části disertační práce je natronová buničina bělena dvěma způsoby, a to bělením bez použití chloru a jeho sloučenin (TCF) a bělením bez elementárního chloru (ECF) s použitím bělicích chemikálií, jako je peroxid vodíku, kyselina peroctová a oxid chloričitý. Získané výsledky byly porovnány s průmyslově vyráběnou sulfátovou a sulfitovou buničinou. Dosažené výsledky ukázaly, že natronová buničina vybělená ECF způsobem s alespoň dvěma chlordioxidovými stupni se jevila jako vhodná vláknina s dostatečně vysokou bělostí, pevností vláken a stupněm polymerace., The dissertation thesis deals with the bleaching of soda pulp cooked from the rapeseed straw. The first part of this thesis is focused on the batch cooking of soda pulp with a relatively low degree of delignification. In the second part, the TCF (totally chlorine-free) and the ECF (elemental chlorine-free) bleaching of soda rapeseed pulp is carried out using chlorine dioxide, hydrogen peroxide, and peracetic acid as bleaching agents. The results obtained for the soda rapeseed pulp were compared with those for the kraft and sulphite pulps produced industrially. It is demonstrated that the ECF four-stage bleaching sequence comprising at least two chlorine dioxide stagesis suitable to yield the bleached soda pulp with sufficient brightness, strength properties, and degree of polymerization compared to the soda pulp after TCF bleaching., Fakulta chemicko-technologická

Purpose: The direct effects of galacto-oligosaccharides (GOS), including Vivinal® GOS syrup (VGOS) and purified Vivinal® GOS (PGOS), on the epithelial integrity and corresponding interleukin-8 (IL-8/CXCL8) release were examined in a Caco-2 cell model for intestinal barrier dysfunction. To investigate structure–activity relationships, the effects of individual DP fractions of VGOS were evaluated. Moreover, the obtained results with GOS were compared with Caco-2 monolayers incubated with fructo-oligosaccharides (FOS) and inulin. Methods: Caco-2 monolayers were pretreated (24 h) with or without specific oligosaccharides or DP fractions of VGOS (DP2 to DP6) before being exposed for 12 or 24 h to the fungal toxin deoxynivalenol (DON). Transepithelial electrical resistance and lucifer yellow permeability were measured to investigate barrier integrity. A calcium switch assay was used to study the reassembly of tight junction proteins. Release of CXCL8, a typical marker for inflammation, was quantified by ELISA. Results: In comparison with PGOS, FOS and inulin, VGOS showed the most pronounced protective effect on the DON-induced impairment of the monolayer integrity, acceleration of the tight junction reassembly and the subsequent CXCL8 release. DP2 and DP3 in concentrations occurring in VGOS prevented the DON-induced epithelial barrier disruption, which could be related to their high prevalence in VGOS. However, no effects of the separate DP GOS fractions were observed on CXCL8 release. Conclusions: This comparative study demonstrates the direct, microbiota-independent effects of oligosaccharides on the intestinal barrier function and shows the differences between individual galacto- and fructo-oligosaccharides. This microbiota-independent effect of oligosaccharides depends on the oligosaccharide structure, DP length and concentration.

Polysialic acid (polySia), consisting of α-(2,8)-linked N-acetylneuraminic acid monomers plays a crucial role in many biological processes. This study presents a novel process for the production of endogenous polySia using Escherichia coli K1 in a disposable bag reactor with wave-induced mixing. Disposable bag reactors provide easy and fast production in terms of regulatory requirements as GMP, flexibility, and can easily be adjusted to larger production capacities not only by scale up but also by parallelization. Due to the poor oxygen transfer rate compared to a stirred tank reactor, pure oxygen was added during the cultivation to avoid oxygen limitation. During the exponential growth phase the growth rate was 0.61 h−1. Investigation of stress-related product release from the cell surface showed no significant differences between the disposable bag reactor with wave-induced mixing and the stirred tank reactor. After batch cultivation a cell dry weight of 6.8 g L−1 and a polySia concentration of 245 mg L−1 were reached. The total protein concentration in the supernatant was 132 mg L−1. After efficient and time-saving downstream processing characterization of the final product showed a protein content of below 0.04 mgprotein/gpolySia and a maximal chain length of ∼90 degree of polymerization. This is the peer reviewed version of the following article: de Vries, I.; Busse, C.; Kopatz, J.; Neumann, H.; Beutel, S.; Scheper, T.: Polysialic acid production using Escherichia coli K1 in a disposable bag reactor. In: Engineering in Life Sciences (2017), which has been published in final form at https://doi.org/10.1002/elsc.201600220. This article may be used for non-commercial purposes in accordance with Wiley Terms and Conditions for Self-Archiving.

Consumption of cocoa and dark chocolate products has been associated with positive health outcomes including reduced onset of cardiovascular disease, inflammation, diabetes, obesity, and platelet disorders. Cocoa polyphenols, putatively responsible for these beneficial activities, are highly impacted by cocoa variety, agronomic effects and processing history. However, the difference in polyphenol concentration and composition between cocoa products originating from different hybrid clones (selected for high yield) or from different fermentation conditions is not fully understood. Detailed polyphenol characterization including determination of total polyphenol and total procyanidin concentrations, and qualitative and quantitative analysis of (mean) degree of polymerization was conducted. Significant differences in total polyphenol and procyanidin concentrations were observed between five genetic clones grown by the USDA-ARS Cocoa Germplasm Repository located in Mayagüez, Puerto Rico. To facilitate cocoa fermentation research in laboratories distant from cocoa harvesting sites, a laboratory-scale cocoa fermentation model system was developed in this study. This model system used dried, unfermented, cocoa beans and simulated pulp medium as the starting material. The model system supported growth of the essential succession of cocoa fermenting microorganisms and generated similar chemical changes to those observed in on-farm cocoa fermentation. Using this model system, the impact of inoculation with proprietary yeast strains Saccharomyces cerevisiae Lev F and Saccharomyces cerevisiae Lev B on cocoa polyphenol concentration and composition was evaluated. Inoculation with both yeast strains resulted in increased fermentation rate and Lev B inoculation resulted in higher total polyphenol and procyandin contents at the end of fermentation. Overall, the present work addressed the influence of cocoa variety selection and fermentation process conditions on the composition and

This paper reports the temperature-dependence of methanol generation and the tensile index under ageing conditions for two paper/oil systems: one consisting of a standard wood Kraft paper and the other of a thermally-upgraded Kraft paper (TUK). A linear correlation between methanol and the tensile index for these paper/oil systems was observed in a previous study at 170 °C. In the current study, the correlation was extended to a large range of temperatures (150–190 °C). The experimental data were fitted with a modified Calvini’s kinetic model, while the Arrhenius equation was used to model the kinetic of changes of the paper’s mechanical properties during ageing. Good agreement with the temperature (lnk vs. 1/T) was observed for the rate constants of the chain-end group production, methanol formation, and the decrease of mechanical properties. The Arrhenius equation applied to this data grouping showed activation energy of 130 ± 29 kJ/mol for the decrease in mechanical strength of the standard Kraft paper, while the value was 118 ± 55 kJ/mol for the TUK paper. These values are of the same order of magnitude as those obtained in this study and in the literature for the depolymerization of cellulose and the generation of methanol that was reported. This confirmed the close relationship between cellulose depolymerization, methanol generation and the reduction of the paper’s mechanical strength during ageing, dominated by the acid hydrolysis mechanism. The results, which can be seen as a benchmark and pave the way to further research, provide an opportunity for applying the proposed correlations to estimate the insulation condition in operating transformers.

Purpose: The direct effects of galacto-oligosaccharides (GOS), including Vivinal® GOS syrup (VGOS) and purified Vivinal® GOS (PGOS), on the epithelial integrity and corresponding interleukin-8 (IL-8/CXCL8) release were examined in a Caco-2 cell model for intestinal barrier dysfunction. To investigate structure–activity relationships, the effects of individual DP fractions of VGOS were evaluated. Moreover, the obtained results with GOS were compared with Caco-2 monolayers incubated with fructo-oligosaccharides (FOS) and inulin. Methods: Caco-2 monolayers were pretreated (24 h) with or without specific oligosaccharides or DP fractions of VGOS (DP2 to DP6) before being exposed for 12 or 24 h to the fungal toxin deoxynivalenol (DON). Transepithelial electrical resistance and lucifer yellow permeability were measured to investigate barrier integrity. A calcium switch assay was used to study the reassembly of tight junction proteins. Release of CXCL8, a typical marker for inflammation, was quantified by ELISA. Results: In comparison with PGOS, FOS and inulin, VGOS showed the most pronounced protective effect on the DON-induced impairment of the monolayer integrity, acceleration of the tight junction reassembly and the subsequent CXCL8 release. DP2 and DP3 in concentrations occurring in VGOS prevented the DON-induced epithelial barrier disruption, which could be related to their high prevalence in VGOS. However, no effects of the separate DP GOS fractions were observed on CXCL8 release. Conclusions: This comparative study demonstrates the direct, microbiota-independent effects of oligosaccharides on the intestinal barrier function and shows the differences between individual galacto- and fructo-oligosaccharides. This microbiota-independent effect of oligosaccharides depends on the oligosaccharide structure, DP length and concentration.

Apart from alkaloids, bioactive properties of Uncaria tomentosa L. have been attributed to its phenolic constituents. Although there are some reports concerning low-molecular-weight polyphenols in U. tomentosa, its polymeric phenolic composition has been scarcely studied. In this study, phenolic-rich extracts from leaves, stems, bark and wood (n = 14) of Uncaria tomentosa plants from several regions of Costa Rica were obtained and analysed in respect to their proanthocyanidin profile determined by a quadrupole-time-of-flight analyser (ESI-QTOF MS). Main structural characteristics found for U. tomentosa proanthocyanidins were: (a) monomer composition, including pure procyanidins (only composed of (epi)catechin units) and propelargonidins (only composed of (epi)afzelechin units) as well as mixed proanthocyanidins; and (b) degree of polymerization, from 3 up to 11 units. In addition, U. tomentosa phenolic extracts were found to exhibit reasonable antioxidant capacity (ORAC (Oxygen Radical Absorbance Capacity) values between 1.5 and 18.8 mmol TE/g) and antimicrobial activity against potential respiratory pathogens (minimum IC of 133 µg/mL). There were also found to be particularly cytotoxic to gastric adenocarcinoma AGS and colon adenocarcinoma SW620 cell lines. The results state the particularities of U. tomentosa proanthocyanidins and suggest the potential value of these extracts with prospective use as functional ingredients.

Enzymatic processing contributes to a better touch and comfort of knitted fabrics. Therefore, in this paper, the influence of pretreatment time to process efficiency was researched. After pretreatment, few creations were designed from such knitted fabric as a material for lightweight jacket, coat or poncho. Models were created with an inspiration for everyday clothes, for different occasions and all generations. For the purpose of researching the influence of process parameters to the scouring efficiency, raw cotton knitted fabric was thoroughly washed, bio-scoured with neutral pectinase, alkali scoured, chemically bleached with hydrogen peroxide, and dyed with basic green dyestuff. The efficiency was monitored through the degree of polymerization, hydrophilicity, whiteness degree, fabric hand and depth in color. Enzimatske obrade pletiva doprinose boljem opipu i udobnosti, te je u ovom radu istražen utjecaj predobrade na ucinkovitost naknadnih procesa. Nakon predobrade osmišljeno je nekoliko kreacija iz predobradenog i oplemenjenog pletiva kao materijala prikladnog za izradu gornjih odjevnih predmeta. Modeli su nastali kao inspiracija za jednostavne odjevne predmete, koji su mogu koristiti za svaki dan, za razlicite prigode i za razlicite generacijske uzraste. U svrhu istraživanja utjecaja procesnih parametara u iskuhavanju, sirovo pamucno pletivo je temeljito oprano, bio-iskuhano neutralnom pektinazom, alkalno iskuhano, kemijski bijeljeno vodikovim peroksidom, te bojadisano baznim bojilom zelenog tona. Ucinci iskuhavanja su praceni kroz stupanj polimerizacije, hidrofilnost, stupanj bjeline, opip te dubinu obojenja, Postprint (published version)

This work focuses on adsorption of polyions onto oppositely charged surfaces and on responses to the addition of a simple monovalent salt as well as to the polyion length (degree of polymerization). We also discuss possible mechanisms underlying observed differences, of the adsorbed amount on silica surfaces at high pH, between seemingly similar polyions. This involves theoretical modeling, utilizing classical polymer density functional theory (DFT). We furthermore investigate; how long- and-short-chain Versions of the polymer adsorb onto carboxymethylatect cellulose, carrying a high negative charge. Interestingly enough, comparing results obtained for the two different surfaces, we observe an opposite qualitative response for the molecular weight. The large polymer adsorbs more strongly at a silica surface, but for cellulose at low salt levels, there are indications that the trend is opposite. Another difference is the very slow adsorption process observed for cellulose, particularly with short polymers; in fact, with short polymers, we were sometimes unable to establish any adsorption plateau at all. We speculate that the slow dynamics is due to a gradual diffusion of short polymers into the cellulose matrix. This phenomenon could also explain why short-chain polymers seem to adsorb more strongly than long-chain ones, at low salt concentrations, provided that the latter then are too large to enter the cellulose pores. Cellulose swelling at high salt concentrations might diminish these differences, leading to more similar adsorbed amounts or even a lower adsorption for short chains., QC 20160715

Procyanidins (PCs) have been extensively investigated for their potential health protective activities, but the prospective bioactivities are limited by their poor bioavailability. The majority of the ingested dose remains unabsorbed and reaches the colon where extensive microbial metabolism occurs. The objectives of these studies are to better understand the roles and activities of PCs in the lower gastrointestinal tract. First, a new high-throughput Ultra Performance Liquid Chromatography-Tandem Mass Spectrometry method was developed to efficiently analyze PCs and an extensive profile of their microbial metabolites. This method is sufficiently sensitive and effective in simultaneously extracting and measuring native PCs and their microbial metabolites in biological samples. Furthermore, administration of grape seed extract increased the expression of gut junction protein occludin and reduced levels of fecal calprotectin, which suggests an improvement of gut barrier integrity and a potential modulation of endotoxemia. Additionally, chronic supplementation of the diet with flavanols did not increase colonic tissue accumulation of PCs or their microbial metabolites over a 12 week feeding study. This was the first long-term study of its kind, and the results indicate that we still do not fully understand the outcome of ingested flavanols in the colon during chronic exposure rather than acute doses. Lastly, new understanding of the microbial metabolism of PCs in the colon has been reached by studying the colon as 4 segments, rather than as a complete unit as previous studies have done. Data show that a gradient is established along the length of the colon for both PCs and their metabolites, with PCs reaching highest concentrations within 3 h after ingestion, while metabolites reach maximum concentrations anywhere form 3-18 h after ingestion. Moreover, data indicate the progressive, step-wise degradation of PCs into small metabolites throughout the length of the colon.

The mechanical performance of two commercial papers used as solid insulation in power transformers, namely standard Kraft and a thermally upgraded Kraft paper, were studied during accelerated aging in Luminol oil at 170 °C. The results show a relationship between the degree of polymerization and the mechanical properties measured by tensile testing. A linear relationship was found between the mechanical properties of paper, the tensile index (Tidx), and the concentration of methanol present in the oil. The methanol chemical marker has been proven to be an accurate assessment tool for the aging of cellulosic paper. The results show a promising tool for correlating the methanol concentration in oil, as an indirect indicator, with the mechanical performance of the paper. This approach can be used to monitor the real state of the cellulose chains in the power transformer insulation paper.

Fructans can act as cryoprotectants and contribute to freezing tolerance in plant species, such as in members of the grass subfamily Pooideae that includes Triticeae species and forage grasses. To elucidate the relationship of freezing tolerance, carbohydrate composition and degree of polymerization (DP) of fructans, we generated transgenic plants in the model grass species Brachypodium distachyon that expressed cDNAs for sucrose:fructan 6-fructosyltransferases (6-SFTs) with different enzymatic properties: one cDNA encoded PpFT1 from timothy grass (Phleum pratense), an enzyme that produces high-DP levans; a second cDNA encoded wft1 from wheat (Triticum aestivum), an enzyme that produces low-DP levans. Transgenic lines expressing PpFT1 and wft1 showed retarded growth; this effect was particularly notable in the PpFT1 transgenic lines. When grown at 22 A degrees C, both types of transgenic line showed little or no accumulation of fructans. However, after a cold treatment, wft1 transgenic plants accumulated fructans with DP = 3-40, whereas PpFT1 transgenic plants accumulated fructans with higher DPs (20 to the separation limit). The different compositions of the accumulated fructans in the two types of transgenic line were correlated with the differences in the enzymatic properties of the overexpressed 6-SFTs. Transgenic lines expressing PpFT1 accumulated greater amounts of mono- and disaccharides than wild type and wft1 expressing lines. Examination of leaf blades showed that after cold acclimation, PpFT1 overexpression increased tolerance to freezing; by contrast, the freezing tolerance of the wft1 expressing lines was the same as that of wild type plants. These results provide new insights into the relationship of the composition of water-soluble carbohydrates and the DP of fructans to freezing tolerance in plants.

Fructans can act as cryoprotectants and contribute to freezing tolerance in plant species, such as in members of the grass subfamily Pooideae that includes Triticeae species and forage grasses. To elucidate the relationship of freezing tolerance, carbohydrate composition and degree of polymerization (DP) of fructans, we generated transgenic plants in the model grass species Brachypodium distachyon that expressed cDNAs for sucrose:fructan 6-fructosyltransferases (6-SFTs) with different enzymatic properties: one cDNA encoded PpFT1 from timothy grass (Phleum pratense), an enzyme that produces high-DP levans; a second cDNA encoded wft1 from wheat (Triticum aestivum), an enzyme that produces low-DP levans. Transgenic lines expressing PpFT1 and wft1 showed retarded growth; this effect was particularly notable in the PpFT1 transgenic lines. When grown at 22 A degrees C, both types of transgenic line showed little or no accumulation of fructans. However, after a cold treatment, wft1 transgenic plants accumulated fructans with DP = 3-40, whereas PpFT1 transgenic plants accumulated fructans with higher DPs (20 to the separation limit). The different compositions of the accumulated fructans in the two types of transgenic line were correlated with the differences in the enzymatic properties of the overexpressed 6-SFTs. Transgenic lines expressing PpFT1 accumulated greater amounts of mono- and disaccharides than wild type and wft1 expressing lines. Examination of leaf blades showed that after cold acclimation, PpFT1 overexpression increased tolerance to freezing; by contrast, the freezing tolerance of the wft1 expressing lines was the same as that of wild type plants. These results provide new insights into the relationship of the composition of water-soluble carbohydrates and the DP of fructans to freezing tolerance in plants.

Flavanols are polyphenols that are known to have many beneficial effects on the body. Cocoa is a major source of these flavanols. However, research on the potential anti-obesity and anti-diabetic health benefits of cocoa flavanols is lacking in the literature. Furthermore, the effect that the size of these flavanols has on the extent of its beneficial properties is also unclear. The objective of this study was to evaluate the dietary effects of cocoa flavanols on the onset of obesity, insulin resistance and impaired glucose tolerance and to determine the impact that the size of these compounds has on the magnitude of this effect. Cocoa extract was fractionated into a monomer-, an oligomer-, and a polymer-rich fraction. Six groups (n=9) of C57BL/6J mice were fed either a control low-fat diet, a control high-fat diet, or a high-fat diet supplemented with 25 mg/kg*BW of cocoa extract or one of the three cocoa fractions. After 12 weeks on these diets, the oligomer-rich fraction proved to be most effective in preventing weight gain, fat mass accumulation, elevated fasting blood glucose and impaired glucose tolerance in diet-induced obese mice. This is the first long-term feeding study to examine the relative activities of cocoa constituents on diet-induced obesity and insulin resistance.

Fructans can act as cryoprotectants and contribute to freezing tolerance in plant species, such as in members of the grass subfamily Pooideae that includes Triticeae species and forage grasses. To elucidate the relationship of freezing tolerance, carbohydrate composition and degree of polymerization (DP) of fructans, we generated transgenic plants in the model grass species Brachypodium distachyon that expressed cDNAs for sucrose:fructan 6-fructosyltransferases (6-SFTs) with different enzymatic properties: one cDNA encoded PpFT1 from timothy grass (Phleum pratense), an enzyme that produces high-DP levans; a second cDNA encoded wft1 from wheat (Triticum aestivum), an enzyme that produces low-DP levans. Transgenic lines expressing PpFT1 and wft1 showed retarded growth; this effect was particularly notable in the PpFT1 transgenic lines. When grown at 22 A degrees C, both types of transgenic line showed little or no accumulation of fructans. However, after a cold treatment, wft1 transgenic plants accumulated fructans with DP = 3-40, whereas PpFT1 transgenic plants accumulated fructans with higher DPs (20 to the separation limit). The different compositions of the accumulated fructans in the two types of transgenic line were correlated with the differences in the enzymatic properties of the overexpressed 6-SFTs. Transgenic lines expressing PpFT1 accumulated greater amounts of mono- and disaccharides than wild type and wft1 expressing lines. Examination of leaf blades showed that after cold acclimation, PpFT1 overexpression increased tolerance to freezing; by contrast, the freezing tolerance of the wft1 expressing lines was the same as that of wild type plants. These results provide new insights into the relationship of the composition of water-soluble carbohydrates and the DP of fructans to freezing tolerance in plants.