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Pezzotti G, Ofuji S, Imamura H, Adachi T, Yamamoto T, Kanamura N, Ohgitani E, Marin E, Zhu W, Mazda O, Togo A, Kimura S, Iwata T, Shiba H, Ouhara K, Aoki T, Kawai T. In Situ Raman Analysis of Biofilm Exopolysaccharides Formed in Streptococcus mutans and Streptococcus sanguinis Commensal Cultures. Int J Mol Sci 2023; 24:ijms24076694. [PMID: 37047667 PMCID: PMC10095091 DOI: 10.3390/ijms24076694] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2023] [Revised: 03/23/2023] [Accepted: 03/27/2023] [Indexed: 04/14/2023] Open
Abstract
This study probed in vitro the mechanisms of competition/coexistence between Streptococcus sanguinis (known for being correlated with health in the oral cavity) and Streptococcus mutans (responsible for aciduric oral environment and formation of caries) by means of quantitative Raman spectroscopy and imaging. In situ Raman assessments of live bacterial culture/coculture focusing on biofilm exopolysaccharides supported the hypothesis that both species engaged in antagonistic interactions. Experiments of simultaneous colonization always resulted in coexistence, but they also revealed fundamental alterations of the biofilm with respect to their water-insoluble glucan structure. Raman spectra (collected at fixed time but different bacterial ratios) showed clear changes in chemical bonds in glucans, which pointed to an action by Streptococcus sanguinis to discontinue the impermeability of the biofilm constructed by Streptococcus mutans. The concurrent effects of glycosidic bond cleavage in water-insoluble α - 1,3-glucan and oxidation at various sites in glucans' molecular chains supported the hypothesis that secretion of oxygen radicals was the main "chemical weapon" used by Streptococcus sanguinis in coculture.
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Affiliation(s)
- Giuseppe Pezzotti
- Ceramic Physics Laboratory, Kyoto Institute of Technology, Sakyo-ku, Matsugasaki, Kyoto 606-8585, Japan
- Department of Immunology, Graduate School of Medical Science, Kyoto Prefectural University of Medicine, Kamigyo-ku, 465 Kajii-cho, Kyoto 602-8566, Japan
- Department of Orthopedic Surgery, Tokyo Medical University, 6-7-1 Nishi-Shinjuku, Shinjuku-ku, Tokyo 160-0023, Japan
- Department of Dental Medicine, Graduate School of Medical Science, Kyoto Prefectural University of Medicine, Kamigyo-ku, Kyoto 602-8566, Japan
- Department of Applied Science and Technology, Politecnico di Torino, Corso Duca degli Abruzzi 24, 10129 Torino, Italy
- Department of Molecular Science and Nanosystems, Ca' Foscari University of Venice, Via Torino 155, 30172 Venice, Italy
| | - Satomi Ofuji
- Ceramic Physics Laboratory, Kyoto Institute of Technology, Sakyo-ku, Matsugasaki, Kyoto 606-8585, Japan
| | - Hayata Imamura
- Ceramic Physics Laboratory, Kyoto Institute of Technology, Sakyo-ku, Matsugasaki, Kyoto 606-8585, Japan
- Department of Dental Medicine, Graduate School of Medical Science, Kyoto Prefectural University of Medicine, Kamigyo-ku, Kyoto 602-8566, Japan
| | - Tetsuya Adachi
- Department of Dental Medicine, Graduate School of Medical Science, Kyoto Prefectural University of Medicine, Kamigyo-ku, Kyoto 602-8566, Japan
| | - Toshiro Yamamoto
- Department of Dental Medicine, Graduate School of Medical Science, Kyoto Prefectural University of Medicine, Kamigyo-ku, Kyoto 602-8566, Japan
| | - Narisato Kanamura
- Department of Dental Medicine, Graduate School of Medical Science, Kyoto Prefectural University of Medicine, Kamigyo-ku, Kyoto 602-8566, Japan
| | - Eriko Ohgitani
- Department of Immunology, Graduate School of Medical Science, Kyoto Prefectural University of Medicine, Kamigyo-ku, 465 Kajii-cho, Kyoto 602-8566, Japan
| | - Elia Marin
- Ceramic Physics Laboratory, Kyoto Institute of Technology, Sakyo-ku, Matsugasaki, Kyoto 606-8585, Japan
- Department of Dental Medicine, Graduate School of Medical Science, Kyoto Prefectural University of Medicine, Kamigyo-ku, Kyoto 602-8566, Japan
| | - Wenliang Zhu
- Ceramic Physics Laboratory, Kyoto Institute of Technology, Sakyo-ku, Matsugasaki, Kyoto 606-8585, Japan
| | - Osam Mazda
- Department of Immunology, Graduate School of Medical Science, Kyoto Prefectural University of Medicine, Kamigyo-ku, 465 Kajii-cho, Kyoto 602-8566, Japan
| | - Azusa Togo
- Department of Biomaterial Sciences, Graduate School of Agricultural and Life Sciences, The University of Tokyo, 1-1-1 Yayoi, Bunkyo-ku, Tokyo 113-8657, Japan
| | - Satoshi Kimura
- Department of Biomaterial Sciences, Graduate School of Agricultural and Life Sciences, The University of Tokyo, 1-1-1 Yayoi, Bunkyo-ku, Tokyo 113-8657, Japan
| | - Tadahisa Iwata
- Department of Biomaterial Sciences, Graduate School of Agricultural and Life Sciences, The University of Tokyo, 1-1-1 Yayoi, Bunkyo-ku, Tokyo 113-8657, Japan
| | - Hideki Shiba
- Department of Biological Endodontics, Graduate School of Biomedical and Health Sciences, Hiroshima University, 1-2-3 Kasumi, Minami-ku, Hiroshima 734-8553, Japan
| | - Kazuhisa Ouhara
- Department of Periodontal Medicine, Graduate School of Biomedical and Health Sciences, Hiroshima University, 1-2-3 Kasumi, Minami-ku, Hiroshima 734-8553, Japan
| | - Takashi Aoki
- Faculty of Fiber Science and Engineering, Kyoto Institute of Technology, Sakyo-ku, Matsugasaki, Kyoto 606-8585, Japan
| | - Toshihisa Kawai
- Department of Oral Science and Translational Research, College of Dental Medicine, Nova Southeastern University, 3301 College Ave, Fort Lauderdale, FL 33314, USA
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Chandrasekar B, Wanke A, Wawra S, Saake P, Mahdi L, Charura N, Neidert M, Poschmann G, Malisic M, Thiele M, Stühler K, Dama M, Pauly M, Zuccaro A. Fungi hijack a ubiquitous plant apoplastic endoglucanase to release a ROS scavenging β-glucan decasaccharide to subvert immune responses. THE PLANT CELL 2022; 34:2765-2784. [PMID: 35441693 PMCID: PMC9252488 DOI: 10.1093/plcell/koac114] [Citation(s) in RCA: 21] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/15/2021] [Accepted: 03/31/2022] [Indexed: 05/04/2023]
Abstract
Plant pathogenic and beneficial fungi have evolved several strategies to evade immunity and cope with host-derived hydrolytic enzymes and oxidative stress in the apoplast, the extracellular space of plant tissues. Fungal hyphae are surrounded by an inner insoluble cell wall layer and an outer soluble extracellular polysaccharide (EPS) matrix. Here, we show by proteomics and glycomics that these two layers have distinct protein and carbohydrate signatures, and hence likely have different biological functions. The barley (Hordeum vulgare) β-1,3-endoglucanase HvBGLUII, which belongs to the widely distributed apoplastic glycoside hydrolase 17 family (GH17), releases a conserved β-1,3;1,6-glucan decasaccharide (β-GD) from the EPS matrices of fungi with different lifestyles and taxonomic positions. This low molecular weight β-GD does not activate plant immunity, is resilient to further enzymatic hydrolysis by β-1,3-endoglucanases due to the presence of three β-1,6-linked glucose branches and can scavenge reactive oxygen species. Exogenous application of β-GD leads to enhanced fungal colonization in barley, confirming its role in the fungal counter-defensive strategy to subvert host immunity. Our data highlight the hitherto undescribed capacity of this often-overlooked EPS matrix from plant-associated fungi to act as an outer protective barrier important for fungal accommodation within the hostile environment at the apoplastic plant-microbe interface.
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Affiliation(s)
| | - Alan Wanke
- Cluster of Excellence on Plant Sciences (CEPLAS), Institute for Plant Sciences, University of Cologne, 50679 Cologne, Germany
- Max Planck Institute for Plant Breeding Research, 50829 Cologne, Germany
| | - Stephan Wawra
- Cluster of Excellence on Plant Sciences (CEPLAS), Institute for Plant Sciences, University of Cologne, 50679 Cologne, Germany
| | - Pia Saake
- Cluster of Excellence on Plant Sciences (CEPLAS), Institute for Plant Sciences, University of Cologne, 50679 Cologne, Germany
| | - Lisa Mahdi
- Cluster of Excellence on Plant Sciences (CEPLAS), Institute for Plant Sciences, University of Cologne, 50679 Cologne, Germany
- Max Planck Institute for Plant Breeding Research, 50829 Cologne, Germany
| | - Nyasha Charura
- Cluster of Excellence on Plant Sciences (CEPLAS), Institute for Plant Sciences, University of Cologne, 50679 Cologne, Germany
| | - Miriam Neidert
- Cluster of Excellence on Plant Sciences (CEPLAS), Institute for Plant Sciences, University of Cologne, 50679 Cologne, Germany
| | - Gereon Poschmann
- Institute of Molecular Medicine, Proteome Research, University Hospital and Medical Faculty, Heinrich-Heine University Düsseldorf, Universitätsstraße 1, 40225 Düsseldorf, Germany
| | - Milena Malisic
- Cluster of Excellence on Plant Sciences (CEPLAS), Institute for Plant Sciences, University of Cologne, 50679 Cologne, Germany
| | - Meik Thiele
- Cluster of Excellence on Plant Sciences (CEPLAS), Institute for Plant Sciences, University of Cologne, 50679 Cologne, Germany
| | - Kai Stühler
- Molecular Proteomics Laboratory, Biomedical Research Centre (BMFZ), Heinrich-Heine University Düsseldorf, Universitätsstraße 1, 40225 Düsseldorf, Germany
| | - Murali Dama
- Cluster of Excellence on Plant Sciences (CEPLAS), Institute for Plant Sciences, University of Cologne, 50679 Cologne, Germany
| | - Markus Pauly
- Institute of Plant Cell Biology and Biotechnology, Heinrich Heine University, 40225 Düsseldorf, Germany
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Marasca E, Zehnder-Wyss O, Boulos S, Nyström L. Estimation of Iron Availability in Modified Cereal β-Glucan Extracts by an in vitro Digestion Model. Front Nutr 2022; 9:879280. [PMID: 35769375 PMCID: PMC9234558 DOI: 10.3389/fnut.2022.879280] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2022] [Accepted: 05/09/2022] [Indexed: 11/28/2022] Open
Abstract
For cereal-based foods rich in dietary fibers, iron bioavailability is known to be poor. For native cereal β-glucan extracts, literature has demonstrated that the main factor impacting the bioavailability is phytic acid, which is often found in association with dietary fibers. During food processing, β-glucan can undergo modifications which could potentially affect the equilibrium between phytic acid, fiber, and iron. In this study, an in vitro digestion was used to elucidate the iron dialysability, and hence estimate iron availability, in the presence of native, chelating resin (Chelex)-treated, oxidised, or partially hydrolysed oat and barley β-glucan extracts (at 1% actual β-glucan concentration), with or without phytase treatment. It was confirmed that pure, phytic acid-free β-glucan polysaccharide does not impede iron availability in cereal foods, while phytic acid, and to a smaller extent, also proteins, associated to β-glucan can do so. Neither Chelex-treatment nor partial hydrolysis, 2,2,6,6-tetramethylpiperidine 1-oxyl (TEMPO) or NaIO4 oxidation significantly influenced the phytic acid content of the β-glucan extracts (ranging 2.0–3.9%; p > 0.05). Consequently, as long as intrinsic phytic acid was still present, the β-glucan extracts blocked the iron availability regardless of source (oat, barley) or Chelex-treatment, partial hydrolysis or NaIO4-oxidation down to 0–8% (relative to the reference without β-glucan extract). Remarkably, TEMPO-oxidation released around 50% of the sequestered iron despite unchanged phytic acid levels in the modified extract. We propose an iron-mobilising effect of the TEMPO product β-polyglucuronan from insoluble Fe(II)/phytate/protein aggregates to soluble Fe(II)/bile salt units that can cross the dialysis membrane. In addition, Chelex-treatment was identified as prerequisite for phytase to dramatically diminish iron retention of the extract for virtually full availability, with implications for optimal iron bioavailability in cereal foods.
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Technical pipeline for screening microbial communities as a function of substrate specificity through fluorescent labelling. Commun Biol 2022; 5:444. [PMID: 35545700 PMCID: PMC9095699 DOI: 10.1038/s42003-022-03383-z] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2021] [Accepted: 04/20/2022] [Indexed: 12/16/2022] Open
Abstract
The study of specific glycan uptake and metabolism is an effective tool in aiding with the continued unravelling of the complexities in the human gut microbiome. To this aim fluorescent labelling of glycans may provide a powerful route towards this target. Here, we successfully used the fluorescent label 2-aminobenzamide (2-AB) to monitor and study microbial degradation of labelled glycans. Both single strain and co-cultured fermentations of microbes from the common human-gut derived Bacteroides genus, are able to grow when supplemented with 2-AB labelled glycans of different monosaccharide composition, degrees of acetylation and polymerization. Utilizing a multifaceted approach that combines chromatography, mass spectrometry, microscopy and flow cytometry techniques, it is possible to better understand the metabolism of labelled glycans in both supernatants and at a single cell level. We envisage this combination of complementary techniques will help further the understanding of substrate specificity and the role it plays within microbial communities. A reductive amination-based fluorophore labelling of complex wood-derived glycans provides a proof-of-principle multi-modal platform for monitoring glycan uptake by bacteria.
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Polysaccharide Structures and Their Hypocholesterolemic Potential. Molecules 2021; 26:molecules26154559. [PMID: 34361718 PMCID: PMC8348680 DOI: 10.3390/molecules26154559] [Citation(s) in RCA: 21] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2021] [Revised: 07/23/2021] [Accepted: 07/24/2021] [Indexed: 12/12/2022] Open
Abstract
Several classes of polysaccharides have been described to have hypocholesterolemic potential, namely cholesterol bioaccessibility and bioavailability. This review will highlight the main mechanisms by which polysaccharides are known to affect cholesterol homeostasis at the intestine, namely the effect (i) of polysaccharide viscosity and its influence on cholesterol bioaccessibility; (ii) on bile salt sequestration and its dependence on the structural diversity of polysaccharides; (iii) of bio-transformations of polysaccharides and bile salts by the gut microbiota. Different quantitative structure–hypocholesterolemic activity relationships have been explored depending on the mechanism involved, and these were based on polysaccharide physicochemical properties, such as sugar composition and ramification degree, linkage type, size/molecular weight, and charge. The information gathered will support the rationalization of polysaccharides’ effect on cholesterol homeostasis and highlight predictive rules towards the development of customized hypocholesterolemic functional food.
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Demuth T, Boulos S, Nyström L. Structural investigation of oxidized arabinoxylan oligosaccharides by negative ionization HILIC-qToF-MS. Analyst 2021; 145:6691-6704. [PMID: 32812535 DOI: 10.1039/d0an01110j] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
Owing to the strong structure-function relationship of polysaccharides, the targeted modification of polysaccharides is attracting widespread interest in various fields, such as food industry, nutritional science, and biomedical research. Apart from intended functionalization, polysaccharide degradation mediated by hydroxyl radicals (HO˙) occurs in various industrial processes such as food processing. In particular, the oxidative degradation of feruloylated arabinoxylan (AX), a linearly-branched polysaccharide in cereals, causes chain scissions, and introduces new functional groups in the fiber, which can potentially modify the physicochemical properties and the functionalities of AX. However, the precise characterization of those structural modifications remains challenging due to the diversity of the oxidation products formed, the high molecular weight, and the relatively low quantity of newly formed functional groups. In this paper, selective (TEMPO-mediated) and random (Fenton) oxidations of several commercial xylo- and arabinoxylan oligosaccharides (A)XOS were studied as model systems by hydrophilic interaction UPLC-MS2 in negative ion resolution mode to identify potential oxidation products. An in-depth identification of acidic (A)XOS oxidation products derived from TEMPO-mediated oxidation provided novel insights in the selective functionalization of isomeric oligosaccharides. Furthermore, MS2 enabled the precise localisation of both glycosidic linkages and functional groups in oxidized (A)XOS. An innovative combination of an enzymatic sample preparation combined with a subsequent HILIC-MS2 analysis enabled the unprecedented comprehensive characterization of Fenton-induced oxidation products derived from AX. In future, this holistic analytical approach will enable the characterization of both selective and non-selective AX oxidation procedures in various applications.
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Affiliation(s)
- Teresa Demuth
- ETH Zurich, Institute of Food, Nutrition and Health, Schmelzbergstrasse 9, 8092 Zurich, Switzerland.
| | - Samy Boulos
- ETH Zurich, Institute of Food, Nutrition and Health, Schmelzbergstrasse 9, 8092 Zurich, Switzerland.
| | - Laura Nyström
- ETH Zurich, Institute of Food, Nutrition and Health, Schmelzbergstrasse 9, 8092 Zurich, Switzerland.
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Kato T, Abe A, Miyadera A, Yamamoto K, Harada T, Ito H, Mizukoshi K, Igarashi T. Non-Destructive Quantification Method for Glucans Using Proton Quantitative Nuclear Magnetic Resonance Spectroscopy. J JPN SOC FOOD SCI 2020. [DOI: 10.3136/nskkk.67.430] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
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Goudar G, Sharma P, Janghu S, Longvah T. Effect of processing on barley β-glucan content, its molecular weight and extractability. Int J Biol Macromol 2020; 162:1204-1216. [DOI: 10.1016/j.ijbiomac.2020.06.208] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2020] [Revised: 04/02/2020] [Accepted: 06/22/2020] [Indexed: 01/23/2023]
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Ovalle R, Chen L, Soll CE, Moore CW, Lipke PN. Regioselective degradation of [beta] 1,3 glucan by ferrous ion and hydrogen peroxide (Fenton oxidation). Carbohydr Res 2020; 497:108124. [PMID: 32977214 DOI: 10.1016/j.carres.2020.108124] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2019] [Revised: 07/22/2020] [Accepted: 08/04/2020] [Indexed: 10/23/2022]
Abstract
Many species use Fe+2 and H2O2 to oxidize a wide variety of compounds to simpler molecules. Both pathogen killing by leukocytes (neutrophils and lymphocytes) and degradation of cellulose by brown rot fungi rely on excretion of Fe+2 ions and H2O2, the Fenton reagent. To elucidate the mechanism of Fenton oxidation of carbohydrates, β1,3 glucan (laminaran), a major fungal wall polysaccharide, was oxidized using a molar ratio of monomer/Fe+2/H2O2 of 10:1:1 (primarily). We labeled the reaction products and profiled them as fluorescent-labeled molecules in polyacrylamide gels and as hydrophobic-tagged molecules using reverse phase liquid chromatography/mass spectrometry (HPLC/MS). Sub-stoichiometric concentrations of Fe+2 and H2O2 fragmented laminaran into smaller molecules containing carbonyl and carboxylic acid groups visible on fluorescent-labeled carbohydrate polyacrylamide gel electrophoresis. HPLC/MS analysis of glucan fragments showed masses consistent with six classes of molecules: aldoses, dialdoses, uronic acids, hexosuloses, aldonic acids, and hexulosonic acids. The results were consistent with published mechanisms where hydrogen radical (H•) abstraction from a C-H or O-H bond begins a cascade of reactions leading to 1) C-C bond cleavage to produce aldose/dialdose pairs; 2) oxo-group (O = ) addition to produce uronic and aldonic acids; 3) hydroxyl group (HO-) addition to produce gluconolactone and hexosuloses; and 4) hexulosonic acids. Most products resulted from regioselective H• abstractions characteristic of oxidations by ferryl-oxo ion [(FeO)+2] or perferryl-oxo ion [(FeO)+3] in close contact with specific positions in the glycan. Therefore, oxidations initiated by regioselectively-bound Fe ions were the predominant initiators of polysaccharide degradations.
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Affiliation(s)
- Rafael Ovalle
- Biology Department, Brooklyn College of the City University of New York (CUNY), Brooklyn, NY, 11210, USA; Biology PhD Program, Graduate Center of the CUNY, New York, NY, 10016, USA.
| | - Lijie Chen
- Biology Department, Brooklyn College of the City University of New York (CUNY), Brooklyn, NY, 11210, USA; Department of Biology, City College of New York of the CUNY, New York, NY, 10031, USA
| | - Clifford E Soll
- Department of Chemistry, Hunter College of the CUNY, New York, NY, 10065, USA
| | - Carol Wood Moore
- Biology PhD Program, Graduate Center of the CUNY, New York, NY, 10016, USA; CUNY School of Medicine, New York, NY, 10031, USA
| | - Peter N Lipke
- Biology Department, Brooklyn College of the City University of New York (CUNY), Brooklyn, NY, 11210, USA; Biology PhD Program, Graduate Center of the CUNY, New York, NY, 10016, USA.
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Structural modifications to water-soluble wheat bran arabinoxylan through milling and extrusion. Carbohydr Polym 2020; 240:116328. [PMID: 32475586 DOI: 10.1016/j.carbpol.2020.116328] [Citation(s) in RCA: 23] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2020] [Revised: 03/25/2020] [Accepted: 04/15/2020] [Indexed: 01/01/2023]
Abstract
Feruloylated arabinoxylan (AX) is one of the most predominant dietary fiber in cereal grains. In recent decades, soluble AX has gained interest, as a result of its well-established health benefits. Apart from enzymatic degradation during cereal storage, food processing causes AX degradation. These reactions lead to structural modifications and influence both the AX functionalities and its health promoting effects. The aim of this study was to investigate the structural modifications and related property changes of health promoting water-extractable (WE) wheat bran AX through grain milling and extrusion. Multi-detector HPSEC revealed a correlation between Mw, conformational changes and the related viscosity behaviour depending on the processing type. Processing caused molecular degradation of insoluble high Mw AX, which increased the solubility significantly. Moreover, extrusion leaded to a more heterogenic AX fine structure. The detailed characterization of processed dietary fiber may help to facilitate the optimized incorporation of AX in health-promoting foods.
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