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Cruz-Rubio JM, Maghuly F, Loeppert R, Praznik W. Determination of Molecular Dimensions of Carbohydrate Polymers (Polysaccharides) by Size Exclusion Chromatography (SEC). Methods Mol Biol 2024; 2788:49-66. [PMID: 38656508 DOI: 10.1007/978-1-0716-3782-1_4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/26/2024]
Abstract
Calibrated size exclusion chromatography (SEC) is a useful tool for the analysis of molecular dimensions of polysaccharides. The calibration takes place with a set of narrow distributed dextran standards and peak position technique. Adapted columns systems and dissolving processes enable for the adequate separation of carbohydrate polymers. Plant-extracted fructan (a homopolymer with low molar mass and excellent water solubility) and mucilage (differently structured, high molar mass heteropolysaccarides that include existing supramolecular structures, and require a long dissolving time) are presented as examples of the versatility of this technique. Since narrow standards similar to the samples (chemically and structurally) are often unavailable, it must be noted that the obtained molar mass values and distributions by this method are only apparent (relative) values, expressed as dextran equivalents.
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Affiliation(s)
- José Manuel Cruz-Rubio
- Plant Functional Genomics Lab, Institute of Molecular Biotechnology, Department of Biotechnology, University of Natural Resources and Life Sciences (BOKU), Vienna, Austria
| | - Fatemeh Maghuly
- Plant Functional Genomics Lab, Institute of Molecular Biotechnology, Department of Biotechnology, University of Natural Resources and Life Sciences (BOKU), Vienna, Austria
| | - Renate Loeppert
- Department of Pharmaceutical Sciences, Division of Pharmaceutical Technology and Biopharmaceutics, University of Vienna, Vienna, Austria
| | - Werner Praznik
- Department of Pharmaceutical Sciences, Division of Pharmaceutical Technology and Biopharmaceutics, University of Vienna, Vienna, Austria.
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2
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Moreno Ravelo RC, Masch JD, Gastl M, Becker T. Effect of molar mass and size of non-alcoholic beer fractions and their relevance toward palate fullness intensity. Food Res Int 2023; 170:112725. [PMID: 37316000 DOI: 10.1016/j.foodres.2023.112725] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2022] [Revised: 01/21/2023] [Accepted: 03/16/2023] [Indexed: 06/16/2023]
Abstract
Palate fullness intensity and mouthfeel descriptors are essential sensory characteristics of non-alcoholic beers (NABs). The descriptor's perception might be influenced by the molar distribution of the non-volatile matrix in cereal-based beverages like NABs. However, only limited information is available on the molar mass of different substances in NABs. This study investigated the role of weight average molar mass (Mw) and size of NABs fractions and their relation to sensory perception. Industrialized bottom-fermented NABs (n = 28) from the German market and NABs produced by different methods were used in this study. A trained sensory panel evaluated palate fullness intensity, mouthfeel, and basic taste descriptors (as additional quality parameters). Asymmetric flow field-flow fractionation was used to fractionate NABs, while Mw was determined by multi-angle light scattering and differential refractive index detectors. The NABs were fractionated into three groups containing different substances: proteins, proteins-polyphenol complexes (P-PC) and low molar mass (non-)starch polysaccharides (LN-SP), and high molar mass (non-)starch polysaccharides (HN-SP). The Mw range of proteins was 18.3-41 kDa, P-PC and LN-SP 43-122.6 kDa, and HN-SP 0.40-2.18·103 kDa. Harmony, defined as the sweet and sour ratio, influenced the palate fullness intensity perception. In the harmonic samples (sour/sweet sensory balanced), the size of HN-SP (> 25 nm) showed a positive correlation to palate fullness intensity. The results suggest the importance of dextrins, arabinoxylan, and β-glucan in modulating the sensory characteristics of harmonic bottom-fermented NABs.
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Affiliation(s)
- Rolando César Moreno Ravelo
- Technical University of Munich, TUM School of Life Sciences, Chair of Brewing and Beverage Technology, 85354 Freising, Germany
| | - Jens Dieter Masch
- Technical University of Munich, TUM School of Life Sciences, Chair of Brewing and Beverage Technology, 85354 Freising, Germany
| | - Martina Gastl
- Technical University of Munich, TUM School of Life Sciences, Chair of Brewing and Beverage Technology, 85354 Freising, Germany.
| | - Thomas Becker
- Technical University of Munich, TUM School of Life Sciences, Chair of Brewing and Beverage Technology, 85354 Freising, Germany
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3
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Vrzoňová R, Čížová A, Račková L, Mečárová J, Bieliková S, Bystrický S. Molar-mass-dependent antibacterial activity of cationic dextran derivatives against resistant nosocomial pathogens. Int J Biol Macromol 2023; 235:123854. [PMID: 36858094 DOI: 10.1016/j.ijbiomac.2023.123854] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2022] [Revised: 02/21/2023] [Accepted: 02/23/2023] [Indexed: 03/03/2023]
Abstract
The rise of various multidrug-resistant bacteria has created a need for new biocompatible and biodegradable antibacterial compounds. Cationic polysaccharides are promising candidates for this role. Therefore, cationic derivatives of commercial dextrans with molar masses of 11 kDa, 76 kDa, 411 kDa, and 1500-2500 kDa and various degrees of substitution (DSQ 0.34-0.52) were prepared and their antimicrobial properties against four gram-negative nosocomial bacteria were tested. As expected, a higher DSQ led to higher efficiency. The best antimicrobial properties were found for derivatives of 411 kDa, followed by 76 kDa and 1500-2000 kDa dextrans. This indicates that there is a certain optimum molar mass with the best antimicrobial properties. However, as molar mass increased, the biocompatibility of cationic dextran steadily decreased, with increased hemagglutination and toxicity being seen for human cells. The derivatives of 76 kDa dextran with higher DSQ (0.40-0.52) were the best antimicrobial agents suitable for further clinical testing.
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Affiliation(s)
- Romana Vrzoňová
- Institute of Chemistry, Slovak Academy of Sciences, Dúbravská cesta 9, 845 38 Bratislava, Slovakia.
| | - Alžbeta Čížová
- Institute of Chemistry, Slovak Academy of Sciences, Dúbravská cesta 9, 845 38 Bratislava, Slovakia.
| | - Lucia Račková
- Institute of Experimental Pharmacology and Toxicology, Centre of Experimental Medicine, Slovak Academy of Sciences, Dúbravská cesta 9, 841 04 Bratislava, Slovakia.
| | - Jana Mečárová
- Institute of Chemistry, Slovak Academy of Sciences, Dúbravská cesta 9, 845 38 Bratislava, Slovakia.
| | - Sandra Bieliková
- Institute of Chemistry, Slovak Academy of Sciences, Dúbravská cesta 9, 845 38 Bratislava, Slovakia.
| | - Slavomír Bystrický
- Institute of Chemistry, Slovak Academy of Sciences, Dúbravská cesta 9, 845 38 Bratislava, Slovakia.
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Wu DT, Zhao YX, Yuan Q, Wang S, Gan RY, Hu YC, Zou L. Influence of ultrasound assisted metal-free Fenton reaction on the structural characteristic and immunostimulatory activity of a β-D-glucan isolated from Dictyophora indusiata. Int J Biol Macromol 2022; 220:97-108. [PMID: 35970367 DOI: 10.1016/j.ijbiomac.2022.08.058] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2022] [Revised: 07/26/2022] [Accepted: 08/09/2022] [Indexed: 11/17/2022]
Abstract
The present study aimed to evaluate the influence of ultrasound assisted H2O2/ascorbic acid reaction on the structural characteristic and immunostimulatory activity of a β-D-glucan isolated from D. indusiata, so as to reveal its potential structure-immunostimulatory activity relationship. A purified β-D-glucan, named as DP, was quickly isolated from D. indusiata, and further identified as a 1,3-β-D-glucan with 1,6-β-D-Glcp as branched chains, which exhibited a rigid rod chain conformation in 0.9 % (w/v) of NaCl solution. Furthermore, results showed that the primary structure of DP was overall stable after the degradation by ultrasound assisted H2O2/ascorbic acid reaction. However, the molar mass and chain conformation of DP obviously changed. In addition, DP and its degraded products exerted remarkable immunostimulatory activity in vitro and in vivo, which could activate the nuclear factor-κB (NF-κB) signaling pathway through toll-like receptor 4 (TLR4). Indeed, the immunostimulatory activity of DP was closely-correlated to its molar mass and chain conformation. An appropriate degradation of molar mass could promote its immunostimulatory activity. While the transformation of chain conformation from rigid rod to random coil could cause the significant decrease of its immunostimulatory activity. These findings are beneficial to better understanding the structure-immunostimulatory activity relationship of β-D-glucans from edible mushrooms.
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Affiliation(s)
- Ding-Tao Wu
- Key Laboratory of Coarse Cereal Processing (Ministry of Agriculture and Rural Affairs), Sichuan Engineering & Technology Research Center of Coarse Cereal Industralization, School of Food and Biological Engineering, Chengdu University, Chengdu 610106, Sichuan, China; Institute of Food Processing and Safety, College of Food Science, Sichuan Agricultural University, Ya'an 625014, Sichuan, China.
| | - Yun-Xuan Zhao
- Institute of Food Processing and Safety, College of Food Science, Sichuan Agricultural University, Ya'an 625014, Sichuan, China
| | - Qin Yuan
- Institute of Food Processing and Safety, College of Food Science, Sichuan Agricultural University, Ya'an 625014, Sichuan, China; State Key Laboratory of Quality Research in Chinese Medicine, Institute of Chinese Medical Sciences, University of Macau, Macao
| | - Shengpeng Wang
- State Key Laboratory of Quality Research in Chinese Medicine, Institute of Chinese Medical Sciences, University of Macau, Macao.
| | - Ren-You Gan
- Key Laboratory of Coarse Cereal Processing (Ministry of Agriculture and Rural Affairs), Sichuan Engineering & Technology Research Center of Coarse Cereal Industralization, School of Food and Biological Engineering, Chengdu University, Chengdu 610106, Sichuan, China; Research Center for Plants and Human Health, Institute of Urban Agriculture, Chinese Academy of Agricultural Sciences, Chengdu 610213, Sichuan, China
| | - Yi-Chen Hu
- Key Laboratory of Coarse Cereal Processing (Ministry of Agriculture and Rural Affairs), Sichuan Engineering & Technology Research Center of Coarse Cereal Industralization, School of Food and Biological Engineering, Chengdu University, Chengdu 610106, Sichuan, China
| | - Liang Zou
- Key Laboratory of Coarse Cereal Processing (Ministry of Agriculture and Rural Affairs), Sichuan Engineering & Technology Research Center of Coarse Cereal Industralization, School of Food and Biological Engineering, Chengdu University, Chengdu 610106, Sichuan, China.
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Pietiäinen S, Moldin A, Ström A, Malmberg C, Langton M. Effect of physicochemical properties, pre-processing, and extraction on the functionality of wheat bran arabinoxylans in breadmaking - A review. Food Chem 2022; 383:132584. [PMID: 35413756 DOI: 10.1016/j.foodchem.2022.132584] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2021] [Revised: 01/27/2022] [Accepted: 02/25/2022] [Indexed: 12/25/2022]
Abstract
Arabinoxylan (AX) is an abundant hemicellulose in wheat bran and an important functional component in bakery products. This review compares preprocessing and extraction methods, and evaluates their effect on AX properties and functionality as a bread ingredient. The extraction process results in AX isolates or concentrates with varying molecular characteristics, indicating that the process can be adjusted to produce AX with targeted functionality. AX functionality in bread seems to depend on AX properties but also on AX addition level and interactions with other components. This review suggests that the use of AX with tailored properties together with properly optimized baking process could help increasing the amount of added fiber in bread while maintaining or even improving bread quality.
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Wyatt PJ. Differential light scattering and the measurement of molecules and nanoparticles: A review. Anal Chim Acta X 2021; 7-8:100070. [PMID: 34485894 PMCID: PMC8406046 DOI: 10.1016/j.acax.2021.100070] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2021] [Revised: 06/15/2021] [Accepted: 06/26/2021] [Indexed: 11/17/2022] Open
Abstract
Within the past few decades, the application of light scattering techniques to a broad range of scientific disciplines has increased significantly, especially in the field of analytical chemistry. The resulting interest in and use of light scattering methods suggests the need for an easily understood introduction and review of material for those new to the method as well as for current users in need of a refresher. In many respects, the theory and its applications may appear so overwhelming for many studying the field for the first time, that they rarely can spend the time just needed to understand the basic measurements and their interpretations. A variety of applications in analytical chemistry especially have resulted in a greater understanding of many of the macromolecular processes themselves from molar mass distributions, to the macromolecular interactions responsible for aggregation processes, to determinations of structure and function. The use of such analytical processes to obtain a better understanding of nanoparticle structure and function has become almost universal. Deriving the distribution of fractionated macromolecules by light scattering. Deriving the distribution of fractionated nanoparticles by light scattering. Deriving the masses of fractionated macromolecules from their scattered light. Deriving the size of nanoparticles from the angular variation of scattered light. Deriving bacterial size and structure by light scattering.
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Affiliation(s)
- Philip J Wyatt
- Wyatt Technology Corporation, 6330 Hollister Avenue, Santa Barbara, 93117, CA, USA
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7
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Barquero A, Agirre A, Leiza JR. Asymmetric-Flow Field-Flow Fractionation of complex waterborne polymer dispersions: Effect of the concentration of water in the measurement of molar mass distributions. J Chromatogr A 2021; 1652:462363. [PMID: 34261024 DOI: 10.1016/j.chroma.2021.462363] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2021] [Revised: 06/15/2021] [Accepted: 06/17/2021] [Indexed: 11/17/2022]
Abstract
Asymmetric-Flow Field-Flow Fractionation is a very powerful technique for measuring the molar mass distribution of polymers with complex microstructures. The analysis of some samples such as self-crosslinkable latexes requires to directly dissolve the polymer dispersion in the eluent (THF) without drying it, and this work studies the effect of the presence of this water in those analysis. Taking a polystyrene latex as model system, it was observed that the measured molar mass and radius of gyration increased as the concentration of water in the sample increased. This was an effect of a decrease in the compatibility between the solvent mixture (THF and water) and the polymer, which formed aggregates, and could be predicted calculating the polymer-solvent interaction parameter. When the study was extended to poly(methyl methacrylate), poly(n-butyl acrylate) and poly(vinyl acetate) the same general trend was observed, however, the impact of the water was less significant as the hydrophilicity of the polymer increased. Most importantly, if the samples with the highest water content were first dissolved in THF and afterwards dried using MgSO4 the measured molar mass and radius of gyration values were the same as for the reference sample (dried in the oven), providing a method to analyze samples that cannot be dried into a film and remove the negative effect of the water at the same time.
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Affiliation(s)
- Aitor Barquero
- POLYMAT, Kimika Aplikatua saila, Kimika Fakultatea, Universidad del País Vasco/Euskal Herriko Unibertsitatea UPV/EHU, Joxe Mari Korta zentroa, Tolosa hiribidea, 72, 20018 Donostia, Spain.
| | - Amaia Agirre
- POLYMAT, Kimika Aplikatua saila, Kimika Fakultatea, Universidad del País Vasco/Euskal Herriko Unibertsitatea UPV/EHU, Joxe Mari Korta zentroa, Tolosa hiribidea, 72, 20018 Donostia, Spain
| | - Jose Ramon Leiza
- POLYMAT, Kimika Aplikatua saila, Kimika Fakultatea, Universidad del País Vasco/Euskal Herriko Unibertsitatea UPV/EHU, Joxe Mari Korta zentroa, Tolosa hiribidea, 72, 20018 Donostia, Spain
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8
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Buksa K, Kowalczyk M, Boreczek J. Extraction, purification and characterisation of exopolysaccharides produced by newly isolated lactic acid bacteria strains and the examination of their influence on resistant starch formation. Food Chem 2021; 362:130221. [PMID: 34098436 DOI: 10.1016/j.foodchem.2021.130221] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2021] [Revised: 05/23/2021] [Accepted: 05/25/2021] [Indexed: 11/19/2022]
Abstract
Exopolysaccharides (EPS) were produced by four newly isolated lactic acid bacteria strains, then further extracted, separated and characterised under standardised conditions. Using a sucrose carbon source, these LAB strains belonging to Weissella confusa/cibaria produced EPS with a dextran high molecular weight fraction. The obtained yields of EPS ranged from 3.2 g/L to 47.1 g/L and outstandingly high yields were obtained using Weissella confusa/cibaria 3MI3 isolated from spontaneous spelt sourdough. After purification the influence of EPS-dextran of molar mass 3,244,000 g/mol on resistant starch formation in wheat starch pastes and pasted samples after temperature-cycled storage was examined. Size exclusion chromatography with post-column derivatisation revealed that a 1.5% share of EPS dextran limited formation of high molar mass resistant starch in starch pastes during storage. This work provides new insight on hindering resistant starch formation by using EPS, which could be efficiently produced in sourdough, thus improving the properties of sourdough bread.
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Affiliation(s)
- Krzysztof Buksa
- University of Agriculture in Krakow, Department of Carbohydrate Technology and Cereal Processing, Balicka 122, 30-149 Krakow, Poland.
| | - Magdalena Kowalczyk
- Institute of Biochemistry and Biophysics, Polish Academy of Sciences, Pawinskiego 5a, 02-106 Warsaw, Poland
| | - Jakub Boreczek
- Institute of Biochemistry and Biophysics, Polish Academy of Sciences, Pawinskiego 5a, 02-106 Warsaw, Poland
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Hastie K, Rayaprolu V, Saphire EO. Analysis of Oligomeric and Glycosylated Proteins by Size-Exclusion Chromatography Coupled with Multiangle Light Scattering. Methods Mol Biol 2021; 2271:343-59. [PMID: 33908019 DOI: 10.1007/978-1-0716-1241-5_24] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register]
Abstract
Analytical size-exclusion chromatography (SEC) is a powerful technique that separates proteins based on their hydrodynamic radii. This approach can provide some rudimentary information about the molecular weight of proteins, but results are also influenced by the in-solution protein conformation and hydrophobicity. SEC also can be affected by nonspecific interactions with the column matrix that influence protein separation. Light scattering (LS) is an absolute and highly accurate measurement of protein molecular weight. Coupling analytical size-exclusion chromatography with multiangle light scattering (SEC-MALS) yields a more robust and accurate method for determining multiple biophysical parameters of proteins while avoiding SEC artifacts. This union of two techniques can help determine the absolute molecular stoichiometry, homo- and heteroassociation of sample components, the nature of protein conjugates, and the molar mass of single molecules and multisubunit complexes. In this chapter, we provide several examples of analysis of glycosylated protein conjugates to showcase the power of SEC-MALS.
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Robin B, Albert C, Beladjine M, Legrand FX, Geiger S, Moine L, Nicolas V, Canette A, Trichet M, Tsapis N, Agnely F, Huang N. Tuning morphology of Pickering emulsions stabilised by biodegradable PLGA nanoparticles: How PLGA characteristics influence emulsion properties. J Colloid Interface Sci 2021; 595:202-11. [PMID: 33823323 DOI: 10.1016/j.jcis.2021.03.061] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2020] [Revised: 03/05/2021] [Accepted: 03/11/2021] [Indexed: 11/20/2022]
Abstract
In this study, we proved that the stabilisation of Pickering emulsions by polymer nanoparticles (NPs) heavily depends on polymer characteristics. We prepared NPs with four poly(lactide-co-glycolide) polymers (PLGA), of different molar masses (14,000 and 32,000 g/mol) and end groups (acid or alkylester). NPs were either bare (without stabilising polymer) or covered by polyvinyl alcohol (PVA). Pickering emulsions were prepared by mixing NP aqueous suspensions with various amounts of oil (Miglyol 812 N). First, NP wettability was directly affected by PLGA end group: ester-ending PLGA led to more hydrophobic NPs, compared to acid-ending PLGA. This effect of the end group could be slightly enhanced with smaller molar mass. Thus, bare PLGA NPs stabilised different types of emulsions (W/O/W and W/O), following Finkle's rule. However, the effect of PLGA characteristics was masked when NPs were covered by PVA, as PVA drove the stabilisation of O/W emulsions. Secondly, PLGA molar mass and end group also influenced its glass transition temperature (Tg), with spectacular consequences on emulsion formation. Indeed, the shortest ester-ending PLGA exhibited a Tg close to room temperature, when measured in the emulsion. This Tg, easily exceeded during emulsification process, led to a soft solid emulsion, stabilised by a network of NP debris.
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Nwokocha LM, Williams PA. Characterization of the polysaccharide from Cola millenii seeds. Int J Biol Macromol 2020; 161:643-647. [PMID: 32534093 DOI: 10.1016/j.ijbiomac.2020.06.068] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2020] [Revised: 06/04/2020] [Accepted: 06/08/2020] [Indexed: 11/26/2022]
Abstract
We have isolated and characterized a water soluble polysaccharide from Cola millenii seeds. It was found to be composed of a total of 59% neutral sugars (mainly rhamnose, galactose and arabinose ~24, 13 and 8% respectively) and 41% uronic acids [mainly galacturonic acid]. The weight and number average molar mass values were found to be 4.7 × 106 g/mol and 3.5 × 106 g/mol, respectively. The polysaccharide exhibited polyelectrolyte properties with the intrinsic viscosity varying with salt concentration. The polysaccharide formed a highly viscous solution in water with apparent zero shear viscosities of 0.59-772 Pa·s at concentrations 0.3-2.5 wt%. The solutions were shear thinning even at very low concentrations. The mechanical spectra showed gel-like characteristics at concentrations >2 wt%. The rheological behavior indicates the polysaccharide has potential for application as a thickener and suspending agent in food, pharmaceutical and cosmetic formulations.
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Affiliation(s)
| | - Peter A Williams
- Center for Water Soluble Polymers, Wrexham Glyndwr University, Wrexham LL 11 2AW, North Wales, UK.
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12
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Moreau C, Tapin-Lingua S, Grisel S, Gimbert I, Le Gall S, Meyer V, Petit-Conil M, Berrin JG, Cathala B, Villares A. Lytic polysaccharide monooxygenases (LPMOs) facilitate cellulose nanofibrils production. Biotechnol Biofuels 2019; 12:156. [PMID: 31249619 PMCID: PMC6589874 DOI: 10.1186/s13068-019-1501-0] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/01/2019] [Accepted: 06/15/2019] [Indexed: 05/06/2023]
Abstract
BACKGROUND Lytic polysaccharide monooxygenases (LPMOs) are copper-dependent enzymes that cleave polysaccharides through an oxidative mechanism. These enzymes are major contributors to the recycling of carbon in nature and are currently used in the biorefinery industry. LPMOs are commonly used in synergy with cellulases to enhance biomass deconstruction. However, there are few examples of the use of monocomponent LPMOs as a tool for cellulose fibrillation. In this work, we took advantage of the LPMO action to facilitate disruption of wood cellulose fibers as a strategy to produce nanofibrillated cellulose (NFC). RESULTS The fungal LPMO from AA9 family (PaLPMO9E) was used in this study as it displays high specificity toward cellulose and its recombinant production in bioreactor is easily upscalable. The treatment of birchwood fibers with PaLPMO9E resulted in the release of a mixture of C1-oxidized oligosaccharides without any apparent modification in fiber morphology and dimensions. The subsequent mechanical shearing disintegrated the LPMO-pretreated samples yielding nanoscale cellulose elements. Their gel-like aspect and nanometric dimensions demonstrated that LPMOs disrupt the cellulose structure and facilitate the production of NFC. CONCLUSIONS This study demonstrates the potential use of LPMOs as a pretreatment in the NFC production process. LPMOs weaken fiber cohesion and facilitate fiber disruption while maintaining the crystallinity of cellulose.
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Affiliation(s)
- Céline Moreau
- UR1268 Biopolymères Interactions Assemblages, INRA, 44316 Nantes, France
| | - Sandra Tapin-Lingua
- InTechFibres Division, FCBA, Domaine Universitaire, CS 90252, 39044 Grenoble Cedex 9, France
| | - Sacha Grisel
- Biodiversité et Biotechnologie Fongiques, INRA, Aix Marseille University, UMR1163, 13009 Marseille, France
| | - Isabelle Gimbert
- Biodiversité et Biotechnologie Fongiques, INRA, Aix Marseille University, UMR1163, 13009 Marseille, France
| | - Sophie Le Gall
- UR1268 Biopolymères Interactions Assemblages, INRA, 44316 Nantes, France
| | - Valérie Meyer
- CTP, Domaine Universitaire, CS 90252, 39044 Grenoble Cedex 9, France
| | | | - Jean-Guy Berrin
- Biodiversité et Biotechnologie Fongiques, INRA, Aix Marseille University, UMR1163, 13009 Marseille, France
| | - Bernard Cathala
- UR1268 Biopolymères Interactions Assemblages, INRA, 44316 Nantes, France
| | - Ana Villares
- UR1268 Biopolymères Interactions Assemblages, INRA, 44316 Nantes, France
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13
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Kock LB, Brummer Y, Exley T, Rhymer C, Storsley J, Xie K, Chu Y, Ou B, Ames NP, Tosh SM, Bordenave N. In vitro assessment of oat β-glucans nutritional properties: An inter-laboratory methodology evaluation. Carbohydr Polym 2018; 200:271-277. [PMID: 30177167 DOI: 10.1016/j.carbpol.2018.07.082] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2018] [Revised: 07/17/2018] [Accepted: 07/27/2018] [Indexed: 10/28/2022]
Abstract
The purpose of this inter-laboratory study was to test the repeatability and reproducibility of an in vitro method aimed at analyzing the physicochemical properties under physiological conditions of β-glucans from foods. After evaluating β-glucans molar mass and quantification methods using five β-glucan controls, four laboratories ran six oat-based products through in vitro digestion, measured β-glucans solubility and viscosity and molar mass of solubilized β-glucans. The determination of the molar mass of β-glucan controls, their viscosity in solution and β-glucans content in food samples exhibited relative standard reproducibility of 20.9-40.9%, 10.2-40.9% and 2.3-14.8%, respectively. After in vitro digestion, relative standard reproducibility ranged 12.1-60.0%, 12.2-64.3% and 9.7-36.3% for molar mass of extracted β-glucans, their viscosity and their solubility, respectively. Although the characterization methods were satisfactory within the limits of current technology, the in vitro extraction contributed significantly to the uncertainty of final characterization.
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Affiliation(s)
- Lindsay B Kock
- PepsiCo, Inc. Global R&D, 617 W Main Street, Barrington, IL 60010, United States
| | - Yolanda Brummer
- Agriculture and Agri-Food Canada Guelph Food Research Center, 93 Stone Road West, Guelph, ON, N1G 5C9, Canada
| | - Tracy Exley
- Agriculture and Agri-Food Canada Cereal Research Center, 196 Innovation Drive, Winnipeg, MB, R3T 2N2, Canada
| | - Camille Rhymer
- Agriculture and Agri-Food Canada Cereal Research Center, 196 Innovation Drive, Winnipeg, MB, R3T 2N2, Canada
| | - Joanne Storsley
- Agriculture and Agri-Food Canada Cereal Research Center, 196 Innovation Drive, Winnipeg, MB, R3T 2N2, Canada
| | - Kenny Xie
- International Chemistry Testing 258 Main Street, Suite 311, Milford, MA, 01757, United States
| | - YiFang Chu
- PepsiCo, Inc. Global R&D, 617 W Main Street, Barrington, IL 60010, United States
| | - Boxin Ou
- International Chemistry Testing 258 Main Street, Suite 311, Milford, MA, 01757, United States
| | - Nancy P Ames
- Agriculture and Agri-Food Canada Cereal Research Center, 196 Innovation Drive, Winnipeg, MB, R3T 2N2, Canada
| | - Susan M Tosh
- Agriculture and Agri-Food Canada Guelph Food Research Center, 93 Stone Road West, Guelph, ON, N1G 5C9, Canada; School of Nutrition Sciences, Faculty of Health Sciences, University of Ottawa 25, University Private, Ottawa, ON K1N 6N5, Canada
| | - Nicolas Bordenave
- PepsiCo, Inc. Global R&D, 617 W Main Street, Barrington, IL 60010, United States; School of Nutrition Sciences, Faculty of Health Sciences, University of Ottawa 25, University Private, Ottawa, ON K1N 6N5, Canada.
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14
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Striegel AM, Ahmad IAH. Determining the Chemical-Heterogeneity-Corrected Molar Mass Averages and Distribution of Poly(styrene- co- t-butyl methacrylate) Using SEC/MALS/UV/DRI. Chromatographia 2018; 81. [PMID: 31274874 DOI: 10.1007/s10337-018-3512-6] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Chemical heterogeneity, defined as the change (or lack thereof) across the molar mass distribution (MMD) in the monomeric ratio of a copolymer, can influence processing and end-use properties such as solubility, gas permeation, conductivity, and the energy of interfacial fracture. Given that each parent homopolymer of the copolymer monomeric components has a different specific refractive index increment (∂n/∂c) from the other component, chemical heterogeneity translates into ∂n/∂c heterogeneity. The latter, in turn, affects the accuracy of the molar mass (M) averages and distributions of the copolymers in question. Here, employing size-exclusion chromatography coupled on-line to multi-angle static light scattering, ultraviolet absorption spectroscopy, and differential refractometry detection, the chemical heterogeneity (given as mass percent styrene) was determined for a poly(styrene-co-t-butyl methacrylate) copolymer. Also determined were the chemical-heterogeneity-corrected M averages and MMD of the copolymer. In the present case, the error in molar mass incurred by ignoring the effects of chemical heterogeneity in the M calculations is seen to reach as high as 53,000 g mol-1 at the high end of the MMD. This error could be much higher, however, in copolymers with higher M or with larger difference among component ∂n/∂c values, as compared to the current analyte.
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Affiliation(s)
- André M Striegel
- Chemical Sciences Division, National Institute of Standards and Technology (NIST), 100 Bureau Drive, MS 8392, Gaithersburg, MD 20899-8392, USA
| | - Imad A Haidar Ahmad
- Process Research and Development, Merck and Co., Inc., Rahway, NJ 07065, USA
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15
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Chen N, Zhao M, Chassenieux C, Nicolai T. Data on the characterization of native soy globulin by SDS-Page, light scattering and titration. Data Brief 2016; 9:749-752. [PMID: 27833934 PMCID: PMC5096597 DOI: 10.1016/j.dib.2016.10.016] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2016] [Revised: 10/13/2016] [Accepted: 10/20/2016] [Indexed: 11/17/2022] Open
Abstract
The data presented in this article are related to the research article entitled Structure of Self-assembled Native Soy Globulin in Aqueous Solution as a Function of the Concentration and the pH by N. Chen, M. Zhao C. Chassenieux, T. Nicolai (2016) [1]. Please refer to this article for interpretation of the data. The protein composition of soy protein isolate (SPI) was characterized by SDS-Page. The molar mass of native soy globulin aggregates formed at different protein concentrations was determined by light scattering as a function of the waiting time. The dependence of the pH on the net charge density of native soy globulins was determined for solutions containing 5 g/L or 2 g/L SPI.
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Affiliation(s)
- Nannan Chen
- College of Light Industry and Food Sciences, South China University of Technology, 510640 Guangzhou, China
- Université du Maine, IMMM UMR-CNRS 6283, Polymères, Colloïdes et Interfaces, 72085 Le Mans cedex 9, France
| | - Mouming Zhao
- College of Light Industry and Food Sciences, South China University of Technology, 510640 Guangzhou, China
| | - Christophe Chassenieux
- Université du Maine, IMMM UMR-CNRS 6283, Polymères, Colloïdes et Interfaces, 72085 Le Mans cedex 9, France
| | - Taco Nicolai
- Université du Maine, IMMM UMR-CNRS 6283, Polymères, Colloïdes et Interfaces, 72085 Le Mans cedex 9, France
- Corresponding author.
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16
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Hutterer C, Schild G, Potthast A. A precise study on effects that trigger alkaline hemicellulose extraction efficiency. Bioresour Technol 2016; 214:460-467. [PMID: 27163434 DOI: 10.1016/j.biortech.2016.04.114] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/16/2016] [Revised: 04/21/2016] [Accepted: 04/22/2016] [Indexed: 06/05/2023]
Abstract
The conversion of paper-grade pulps into dissolving pulps requires efficient strategies and process steps to remove low-molecular noncellulosic macromolecules generally known as hemicelluloses. Current strategies include alkaline extractions and enzymatic treatments. This study focused on the evaluation of extraction efficiencies in alkaline extractions of three economically interesting hardwood species: beech (Fagus sylvatica), birch (Betula papyrifera), and eucalyptus (Eucalyptus globulus). Substrate pulps were subjected to alkaline treatments at different temperatures and alkalinities using white liquor as the alkali source, followed by analyses of both pulps and hemicellulose-containing extraction lyes. The extracted hardwood xylans have strong potential as an ingredient in the food and pharmaceutical industries. Subsequent analyses revealed strong dependencies of the extraction efficiencies and molar mass distributions of hemicelluloses on the process variables of temperature and effective alkalinity. The hemicellulose content of the initial pulps, the hardwood species, and the type of applied base played minor roles.
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Affiliation(s)
| | | | - Antje Potthast
- Universität für Bodenkultur Wien, Department für Chemie, Muthgasse 18, A-1190 Wien, Austria.
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17
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Kupetz M, Sacher B, Becker T. Impact of flavouring substances on the aggregation behaviour of dissolved barley β-glucans in a model beer. Carbohydr Polym 2016; 143:204-11. [PMID: 27083361 DOI: 10.1016/j.carbpol.2016.01.070] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2015] [Revised: 01/27/2016] [Accepted: 01/30/2016] [Indexed: 11/28/2022]
Abstract
Structural polymers such as cereal β-glucan may cause various processing problems in beverage industry depending on concentration, molar size distribution and agglomeration behaviour. In this context, influences of the beer volatiles dodecanoic acid, octyl butanoate, ethyl decanoate and decyl acetate on molar mass and radii of barley β-glucan were investigated in ethanolic (4% w/w) model solution. After addition of 100mg/l ethyl decanoate and decyl acetate to the β-glucan solution, a wider-ranging molar mass distribution could be observed by means of asymmetric field-flow-fractionation. Due to agglomeration, average molar mass of β-glucan standard (MW=6.8×10(6)g/mol) increased by 2×10(6)g/mol (P<0.05) in solution containing decyl acetate. Furthermore, a significant growth (P<0.05) from 86 to 102 nm in gyration radius was measured. The obtained results elucidate the importance of fatty acid derived flavouring substance composition in beer regarding the aggregation behaviour of β-glucan.
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Affiliation(s)
- M Kupetz
- Lehrstuhl für Brau- und Getränketechnologie, Technische Universität München, Weihenstephan, Weihenstephaner Steig 20, 85354 Freising, Germany
| | - B Sacher
- Lehrstuhl für Brau- und Getränketechnologie, Technische Universität München, Weihenstephan, Weihenstephaner Steig 20, 85354 Freising, Germany.
| | - T Becker
- Lehrstuhl für Brau- und Getränketechnologie, Technische Universität München, Weihenstephan, Weihenstephaner Steig 20, 85354 Freising, Germany
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18
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Buksa K, Praznik W, Loeppert R, Nowotna A. Characterization of water and alkali extractable arabinoxylan from wheat and rye under standardized conditions. J Food Sci Technol 2016; 53:1389-98. [PMID: 27570263 DOI: 10.1007/s13197-015-2135-2] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Revised: 11/19/2015] [Accepted: 12/11/2015] [Indexed: 11/29/2022]
Abstract
Arabinoxylans (AXs) are an important component of wheat and rye dough. They bind water, contribute to the formation of viscous dough and improve the quality of bread. For the application of AX fractions in bread making process, it is useful to record a quality profile of wheat fractions compared to the quality profile of rye fractions under standardized conditions. In this work water and alkali extractable AX containing fractions, from wheat- and rye wholemeal, were extracted under standardized conditions and characterized. For analysis of composition, structural features, and molecular dimension a combination of chemical, physicochemical, enzymatic and chromatographic techniques was applied. The molar mass distributions obtained by means of an innovative colorimetric pentose detection in the eluted SEC fractions were comparable for all under standardized conditions extracted AXs. The determined molar masses of AXs extracted both from wheat- and from rye grain were close to 2.0 × 10(5) g/mol for water extractable AXs and 3.0 × 10(5) g/mol for alkali extractable AXs. Different susceptibility to endoxylanase treatment, having been observed as differences in the SEC profiles, may be evidence of structural differences between AXs depending on their origin. The viscosities of AX solutions were strongly influenced by their molar mass and structure; samples being less susceptible to endoxylanase provided solutions of higher viscosity.
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Affiliation(s)
- Krzysztof Buksa
- Faculty of Food Technology, Department of Carbohydrates Technology, University of Agriculture Kraków, ul. Balicka 122, 30149 Kraków, Poland
| | - Werner Praznik
- Department of Pharmaceutical Technology and Biopharmaceutics, University of Vienna, Althanstrasse 14, 1090 Vienna, Austria
| | - Renate Loeppert
- Department of Pharmaceutical Technology and Biopharmaceutics, University of Vienna, Althanstrasse 14, 1090 Vienna, Austria
| | - Anna Nowotna
- Faculty of Food Technology, Department of Carbohydrates Technology, University of Agriculture Kraków, ul. Balicka 122, 30149 Kraków, Poland
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19
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Wright TG, Pfukwa H, Pasch H. Advanced analytical methods for the structure elucidation of polystyrene-b-poly(n-butyl acrylate) block copolymers prepared by reverse iodine transfer polymerisation. Anal Chim Acta 2015; 892:183-94. [PMID: 26388490 DOI: 10.1016/j.aca.2015.08.005] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2015] [Revised: 08/07/2015] [Accepted: 08/10/2015] [Indexed: 10/23/2022]
Abstract
Reverse iodine transfer polymerisation (RITP) is a living radical polymerisation technique that has shown to be feasible in synthesising segmented styrene-acrylate copolymers. Polymers synthesised via RITP are typically only described regarding their bulk properties using nuclear magnetic resonance spectroscopy and size exclusion chromatography. To fully understand the complex composition of the polymerisation products and the RITP reaction mechanism, however, it is necessary to use a combination of advanced analytical methods. In the present RITP procedure, polystyrene was synthesised first and then used as a macroinitiator to synthesise polystyrene-block-poly(n-butyl acrylate) (PS-b-PBA) block copolymers. For the first time, these PS-b-PBA block copolymers were analysed by a combination of SEC, in situ(1)H NMR and HPLC. (1)H NMR was used to determine the copolymer composition and the end group functionality of the samples, while SEC and HPLC were used to confirm the formation of block copolymers. Detailed information on the living character of the RITP process was obtained.
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Affiliation(s)
- Trevor Gavin Wright
- Department of Chemistry and Polymer Science, University of Stellenbosch, Private Bag X1, 7602 Matieland, South Africa
| | - Helen Pfukwa
- Department of Chemistry and Polymer Science, University of Stellenbosch, Private Bag X1, 7602 Matieland, South Africa
| | - Harald Pasch
- Department of Chemistry and Polymer Science, University of Stellenbosch, Private Bag X1, 7602 Matieland, South Africa.
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20
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Alinat E, Delaunay N, Archer X, Gareil P. Correlating molar masses of nitrocelluloses with their intrinsic viscosities measured using capillary electrophoresis instrumentation. Carbohydr Polym 2015; 128:99-104. [PMID: 26005144 DOI: 10.1016/j.carbpol.2015.04.013] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2015] [Revised: 03/30/2015] [Accepted: 04/12/2015] [Indexed: 10/23/2022]
Abstract
Specific viscosities for a set of six nitrocellulose (NC) standards comprising three different mass-average molar masses (between 20,000 and 300,000 g mol(-1)) of two different nitrogen contents (11.2 and 12.1%) were measured at 20 °C in tetrahydrofuran, using capillary electrophoresis instrumentation as a bench-top viscometer in frontal mode. Intrinsic viscosities were derived applying Huggins' and Kraemer's models, showing excellent convergence of both models at infinitely diluted polymer concentration. Good overall consistency was shown between viscosity data experimentally acquired by this new protocol and the mass-average molar masses provided by the manufacturers. This simple protocol should be of interest for a better understanding of the solvent interaction given by this complex polymer, and beyond this, for tailoring NC solutions devoted to film deposition, and for the determination of mass-average molar masses of unknown NC samples.
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Affiliation(s)
- Elodie Alinat
- PSL Research University, Chimie ParisTech, Laboratory of Physicochemistry of Electrolytes, Colloids and Analytical Sciences (PECSA), 11 rue Pierre et Marie Curie, 75005 Paris, France; Central Laboratory of Police Prefecture (LCPP), 39 bis rue de Dantzig, 75015 Paris, France; CNRS, UMR 7195, 11 rue Pierre et Marie Curie, 75005 Paris, France; Sorbonne Université, UPMC, Université Paris 6, 4 Place Jussieu, 75005 Paris, France.
| | - Nathalie Delaunay
- PSL Research University, Chimie ParisTech, Laboratory of Physicochemistry of Electrolytes, Colloids and Analytical Sciences (PECSA), 11 rue Pierre et Marie Curie, 75005 Paris, France; CNRS, UMR 7195, 11 rue Pierre et Marie Curie, 75005 Paris, France; Sorbonne Université, UPMC, Université Paris 6, 4 Place Jussieu, 75005 Paris, France.
| | - Xavier Archer
- Central Laboratory of Police Prefecture (LCPP), 39 bis rue de Dantzig, 75015 Paris, France.
| | - Pierre Gareil
- PSL Research University, Chimie ParisTech, Laboratory of Physicochemistry of Electrolytes, Colloids and Analytical Sciences (PECSA), 11 rue Pierre et Marie Curie, 75005 Paris, France; CNRS, UMR 7195, 11 rue Pierre et Marie Curie, 75005 Paris, France; Sorbonne Université, UPMC, Université Paris 6, 4 Place Jussieu, 75005 Paris, France.
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21
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Rieder A, Knutsen SH, Ulset AST, Christensen BE, Andersson R, Mikkelson A, Tuomainen P, Maina N, Ballance S. Inter-laboratory evaluation of SEC-post-column calcofluor for determination of the weight-average molar mass of cereal β-glucan. Carbohydr Polym 2015; 124:254-64. [PMID: 25839819 DOI: 10.1016/j.carbpol.2015.02.019] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2014] [Revised: 02/13/2015] [Accepted: 02/16/2015] [Indexed: 11/25/2022]
Abstract
Even though size exclusion chromatography (SEC) with post column addition of calcofluor (SEC-calcofluor) has been used for the determination of cereal β-glucan molar mass in foods for many years, there is a lack of systematic evaluation of the method. To address this issue a set of suitable β-glucan standards were generated by preparative SEC and their molar mass characteristics were determined by analytical multi-detection SEC (refractive index (RI), light scattering). Each standard was then analysed by SEC-calcofluor at three different labs. As a direct comparison, the analyses were repeated with a RI detector. For SEC-calcofluor accurate measurements of weight average molar mass (Mw) can be made for β-glucan populations within 10-500×10(3)g/mol. Above this molar mass threshold there is an increasing tendency for underestimation of Mw. Precipitation of some β-glucan-calcofluor complexes may have delayed their transport into the detector.
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Affiliation(s)
- Anne Rieder
- Nofima, Norwegian Institute for Food, Fisheries and Aquaculture Research, PB 210, N-1431 Ås, Norway.
| | - Svein Halvor Knutsen
- Nofima, Norwegian Institute for Food, Fisheries and Aquaculture Research, PB 210, N-1431 Ås, Norway.
| | - Ann-Sissel T Ulset
- NOBIPOL, Department of Biotechnology, Norwegian University of Science and Technology (NTNU), N-7491 Trondheim, Norway.
| | - Bjørn E Christensen
- NOBIPOL, Department of Biotechnology, Norwegian University of Science and Technology (NTNU), N-7491 Trondheim, Norway.
| | - Roger Andersson
- Department of Food Science, Swedish University of Agricultural Sciences, PO Box 7051, SE-750 07 Uppsala, Sweden.
| | - Atte Mikkelson
- VTT Technical Research Center of Finland, PO Box 1000, FI-02044 VTT Espoo, Finland.
| | - Päivi Tuomainen
- Department of Food and Environmental Sciences, University of Helsinki, PO Box 66, A3039 Helsinki, Finland.
| | - Ndegwa Maina
- Department of Food and Environmental Sciences, University of Helsinki, PO Box 66, A3039 Helsinki, Finland.
| | - Simon Ballance
- Nofima, Norwegian Institute for Food, Fisheries and Aquaculture Research, PB 210, N-1431 Ås, Norway.
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22
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Riggs AF, Riggs CK. The self-association of the giant hemoglobin from the earthworm, Lumbricus terrestris. Biochim Biophys Acta 2014; 1844:1071-5. [PMID: 24631544 DOI: 10.1016/j.bbapap.2014.03.004] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/11/2013] [Revised: 02/24/2014] [Accepted: 03/04/2014] [Indexed: 10/25/2022]
Abstract
BACKGROUND The crystallographic structure of the gigantic hemoglobin (erythrocruorin) of the annelid worm, Lumbricus terrestris, provides a molar mass of 3.6MDa for the hexagonal bilayer structure. Prior to this determination, some light-scattering and ultracentrifugal measurements indicated higher masses: 4.1-4.4MDa. Values of 3.6MDa were attributed to dissociation or subunit loss. However, early electron microscopy of the giant hemoglobin from a related annelid, Eumenia crassa by Öster Levin, showed that the hexagonal bilayer molecules were present mostly as oligomers; few were monomeric. METHODS Measurements by light-scattering of solutions of Lumbricus hemoglobin resolved by size-exclusion chromatography have been used to determine the weight-average molar mass of self-associating proteins. The X-ray structure has been re-examined. RESULTS Our measurements show that both 3.6MDa monomers and self-association products are present as a mixture. Analysis of the X-ray structure indicates several different kinds of monomer-monomer interactions. CONCLUSIONS We propose that the measured masses of Lumbricus hemoglobin as high as 4.4MDa, result from oligomerization. These masses would result from the presence of an array of oligomers of various sizes together with monomers of 3.6MDa. Furthermore, several different kinds of monomer-monomer interactions are clearly evident in the X-ray structure as well as in solution. GENERAL SIGNIFICANCE The results demonstrate that self-association of monomers of the hemoglobin of Lumbricus terrestris explains the high molar masses of 4.1-4.4MDa previously observed.
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Affiliation(s)
- Austen F Riggs
- Section of Neurobiology, University of Texas at Austin, 1 University Station CO920, Austin, TX 78712, USA.
| | - Claire K Riggs
- Section of Neurobiology, University of Texas at Austin, 1 University Station CO920, Austin, TX 78712, USA
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Fouzas S, Häcki C, Latzin P, Proietti E, Schulzke S, Frey U, Delgado-Eckert E. Volumetric capnography in infants with bronchopulmonary dysplasia. J Pediatr 2014; 164:283-8.e1-3. [PMID: 24161220 DOI: 10.1016/j.jpeds.2013.09.034] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/02/2013] [Revised: 08/28/2013] [Accepted: 09/16/2013] [Indexed: 11/18/2022]
Abstract
OBJECTIVES To assess the feasibility of using volumetric capnography in spontaneously breathing small infants and its ability to discriminate between infants with and without bronchopulmonary dysplasia (BPD). STUDY DESIGN Lung function variables for 231 infants (102 term, 52 healthy preterm, 77 BPD), matched for post-conceptional age of 44 weeks, were collected. BPD was defined as supplemental oxygen requirement at 36 weeks post-menstrual age. Tidal breath-by-breath volume capnograms were obtained by mainstream capnography. The capnographic slope of phase II (SII) and slope of phase III (SIII) were calculated and compared between study groups. The effect of BPD, tidal volume (VT), respiratory rate (RR), and prematurity on the magnitude of the slopes was assessed. RESULTS SII was steeper in infants with BPD (100 ± 28/L) compared with healthy preterm (88 ± 22/L; P = .007) and term infants (79 ± 18/L; P < .001), but this finding was attributed to differences in VT, RR, and gestational age. SIII was steeper in the BPD group (26.8 ± 14.1/L) compared with healthy preterm (16.2 ± 6.2/L; P < .001) and term controls (14.8 ± 5.4/L; P < .001). BPD was a significant predictor of SIII independently of VT, RR, and gestational age. The ability of SIII to discriminate between BPD and controls was significantly higher compared with lung clearance index (area under the curve 0.83 vs 0.56; P < .001). CONCLUSIONS Volumetric capnography may provide valuable information regarding functional lung alterations related to BPD and might be considered as an alternative to more involved lung function techniques for monitoring chronic lung disease during early infancy.
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Affiliation(s)
- Sotirios Fouzas
- Respiratory Research Group, University Children's Hospital of Basel (UKBB), Basel, Switzerland; Pediatric Respiratory Unit, University Hospital of Patras, Patras, Greece.
| | - Christoph Häcki
- Respiratory Research Group, University Children's Hospital of Basel (UKBB), Basel, Switzerland
| | - Philipp Latzin
- Respiratory Research Group, University Children's Hospital of Basel (UKBB), Basel, Switzerland; Pediatric Respiratory Medicine, University Children's Hospital of Bern, Bern, Switzerland
| | - Elena Proietti
- Respiratory Research Group, University Children's Hospital of Basel (UKBB), Basel, Switzerland; Pediatric Respiratory Medicine, University Children's Hospital of Bern, Bern, Switzerland
| | - Sven Schulzke
- Respiratory Research Group, University Children's Hospital of Basel (UKBB), Basel, Switzerland
| | - Urs Frey
- Respiratory Research Group, University Children's Hospital of Basel (UKBB), Basel, Switzerland
| | - Edgar Delgado-Eckert
- Respiratory Research Group, University Children's Hospital of Basel (UKBB), Basel, Switzerland
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