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Feruloylated side-chain oligosaccharide substituents are a distinctive feature of cereal grains' arabinoxylans (AX), but less is known about non-feruloylated oligosaccharide side-chain substituents. In this study we explored non-feruloylated disaccharide side-chains from corn (Zea mays L.) AX that had not been exposed to alkaline conditions and successfully isolated and unequivocally characterized the structure, α-d-xylopyranosyl-(1 → 3)-l-arabinose. This structure is uniquely different from the oligosaccharide portion of the comparable feruloylated disaccharide compound. Qualitative screening showed that this non-feruloylated disaccharide is also present in wheat (Triticum aestivum L.), oats (Avena sativa L.), and popcorn (Zea mays L. var. everta). β-d-Xylopyranosyl-(1 → 2)-l-arabinose, the carbohydrate motif from feruloylated oligosaccharide side-chain substituents, was not found in a non-feruloylated form. Our data imply that non-feruloylated β-d-xylopyranosyl-(1 → 2)-l-arabinose side-chains may not be an authentic component of cereal AX, and that structural models of AX should be revised accordingly. Non-feruloylated oligosaccharide side-chains are indeed an authentic substituent of cereal AX, but their carbohydrate structures sharply diverge from their feruloylated counterparts., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Ltd. All rights reserved.)

With water access challenged, there is a need to develop efficient and sustainable alternatives for water purification. Here, cellulose nanofibrils (CNFs) isolated from three source materials (softwood, soybean hulls and oat straw) were compared for the generation of hydrogels beads, and compared as support and reducing agent for silver nanoparticles formation. The silver-functionalized hydrogel beads (Ag-CNFs) were characterized, and the surface energy and specific surface area were evaluated. Antimicrobial testing was conducted to assess the efficacy of the Ag-CNFs against E. coli. The results showed that the Ag-CNFs had a higher specific surface area and lower surface energy compared with unmodified CNFs. Softwood-based Ag-CNFs exhibited the highest silver content and specific surface area, while the soybean hull based showed the highest hydrophobic character. The silver-functionalized soybean hull beads (Ag-sbCNF) showed the highest efficacy in reducing the growth of bacteria. Overall, this study highlights the potential of silver-functionalized CNFs hydrogel beads as a promising environmentally friendly and sustainable material for water filtration and disinfection. The findings also suggest that lower surface energy of the Ag-CNFs play an important role in their antimicrobial effect on tested water by enabling shorter retention, providing useful insights into the design of future water filtration materials., Competing Interests: Declaration of competing interest The authors declare the following financial interests/personal relationships which may be considered as potential competing interests: Maria S. Peresin reports financial support was provided by National Science Foundation. Maria S. Peresin reports financial support was provided by National Institute of Food and Agriculture. If there are other authors, they declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Ltd. All rights reserved.)

Oat β-(1 → 3, 1 → 4)-d-glucan (OBG), a linear polysaccharide primarily found in oat bran, has been demonstrated to possess immunomodulatory properties and regulate gut microbiota. This study aimed to investigate the impact of low molecular weight (Mw) OBG (155.2 kDa) on colonic injury and allergic symptoms induced by food allergy (FA), and to explore its potential mechanism. In Experiment 1, results indicated that oral OBG improved colonic inflammation and epithelial barrier, and significantly relieved allergy symptoms. Importantly, the OBG supplement altered the gut microbiota composition, particularly increasing the abundance of Lachnospiraceae and its genera, and promoted the production of short-chain fatty acids, especially butyrate. However, in Experiment 2, the gut microbial depletion eliminated these protective effects of OBG on the colon in allergic mice. Further, in Experiment 3, fecal microbiota transplantation and sterile fecal filtrate transfer directly validated the role of OBG-mediated gut microbiota and its metabolites in relieving FA and its induced colonic injury. Our findings suggest that low Mw OBG can alleviate FA-induced colonic damage by increasing Lachnospiraceae abundance and butyrate production, and provide novel insights into the health benefits and mechanisms of dietary polysaccharide intervention for FA., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Ltd. All rights reserved.)

We propose a closed-loop pretreatment process, wherein volatiles produced during steam explosion pretreatment were recovered and reintroduced as acid catalysts into the pretreatment system. The volatiles were separated through a drastic decompression process followed by a steam explosion process and recovered as a liquified catalyst (LFC) through a heat exchanger. The LFC effectively served as an acid catalyst for hemicellulose hydrolysis, significantly decreasing residence time from 90 min to 30 min to achieve 80 % conversion yield at 170 °C. Hydrolysates with high content of lower molecular weight oligomeric sugars were obtained using LFC, and were considered advantageous for application as prebiotics. These results are attributed to the complementary features of acetic acid and furfural contained within the LFC. Computational simulation using Aspen Plus was used to investigate the effects of recycling on LFC, and it demonstrated the feasibility of the catalyst-recirculating system. A validation study was conducted based on simulation results to predict the actual performance of the proposed pretreatment system. Based on these results, the recirculating system was predicted to improve the conversion yield and low-molecular weight oligomers yield by 1.5-fold and 1.6-fold, respectively., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Ltd. All rights reserved.)

Water-extractable β-glucan with high molar mass (HM) determines health benefits of oat food. Oat β-glucan was extracted by a standardized in vitro digestion method and co-existing water-extractable polysaccharide (WEP) fraction and its HM-arabinoxylan (HM-AX) subfraction were isolated to identify their highly acid-resistant subunit and investigate molecular interactions between constituent polymers. The WEP and HM-AX samples consisted of arabinoxylans (AXs) (74 and 76 %, respectively), however, cellulose constituted the secondary component (6.6 and 12.8 %, respectively). Multi-detection HPSEC along with specific enzymatic hydrolysis of AXs revealed the presence of the HM-xylan domain (16 and 34 %, respectively) built of numerous single- and multi-component populations with random coil and rod-like conformations, which were embedded in a xylan matrix with spherical conformation and controlled the macromolecular shape. Unlike single-component populations, the multi-component ones were resistant to hydrolytic action of AX-hydrolyzing enzymes and represented the subunits that anchor matrix polysaccharides onto cellulose surface. These results indicate that water-extractable β-glucan macromolecule comprises as integral element a cellulose core with two linking populations, HM-xylan and low molar mass glucomannan, which are surrounded by a feruloylated AX-arabinan-arabinogalactan composite and next laminated by β-glucan matrix. The stiff cellulose-xylan backbone is the basis of HM β-glucan organization, controlled by its cellulose-like segments., Competing Interests: Declaration of competing interest The authors declare no conflicts of interest., (Copyright © 2023 Elsevier Ltd. All rights reserved.)

Oat is a promising grain well-incorporated into human diet due to the presence of multiple nutrients in composition and its unique health-enhancing attributes. Similar to other cereals, starch is the most important component of the oat kernel, which makes up at least 60 % of the grain's dry weight. Considering the need to access new sources of starch with a broad range of capabilities, oat starch has experienced various modifications by physical and chemical strategies. Thus, this study aims to comprehensively review the impacts of various physical and chemical modifications on the physicochemical, functional, as well as digestibility properties of oat starch. Besides, the effects of oat starch combination with other biomacromolecules (whey protein isolate, caseinate, gums and lipids) on mentioned criteria were also reviewed. In conclusion, various modification methods could properly enhance the physicochemical attributes and digestibility of oat starch for its further successful application in food and pharmaceutical formulations., Competing Interests: Declaration of competing interest None., (Copyright © 2022 Elsevier Ltd. All rights reserved.)

High molar mass (HM) β-glucan present in oat products can reduce the risk of diet-related diseases, mainly owing to significantly increased digesta viscosity in human small intestine. To verify a research hypothesis that arabinoxylan (AX) present in oat water extract is associated with HM-β-glucan and thus may influence its functionality, multi-detection HPSEC coupled with enzymatic hydrolysis, sugar and 1 H NMR analyses were performed. Isolated cell wall polysaccharide fraction comprised branched AX (arabinose-to-xylose ratio, Ara/Xyl ~ 0.8) and arabinogalactan-protein (AG-P). Nevertheless, it contained (10%) unbranched HM-xylan subfraction (weight-average molar mass, M w  ~ 3153 kg/mol), which was aggregated with β-glucan (M w  ~ 1029-1589 kg/mol) through its HM cellulose-like region. Of the two low molar mass-AXs (LM-AXs) isolated, the first having C(O)-3-monosubstituted and C(O)-2,3-disubstituted β-d-xylopyranosyl residues was covalently interlinked to HM-xylan. The second highly feruloylated, containing C(O)-3- and C(O)-2-monosubstituted units, was tightly bound to AG-P with terminal and 5-linked α-L-arabinofuranosyl residues, and non-covalently associated with LM-β-glucan subfraction., (Copyright © 2021 Elsevier Ltd. All rights reserved.)

Circadian disruption-induced metabolic syndrome (CDIMS) involves body weight gain, changes in blood profile and gut microbiota. In this study, CDIMS was induced by shifted light dark cycle (SLDC) in C57BL/6J mice. Dietary intervention by oral administration of oat β-glucan (a polymeric prebiotic) alleviated CDIMS when compared to chicory inulin/fructan (an oligomeric prebiotic) and melatonin (a chronobiotic). Oat β-glucan reversed the increase in body weight, liver weight-to-body weight ratio and plasma leptin concentration as well as restored glucose tolerance. In altering gut microbiota, oat β-glucan increased the species richness, reversed the populations of 7 bacterial genera and increased butyrate producers including Ruminococcaceae and Lachnospiraceae which enhance gut barrier protection and regulate glucose homeostasis. Correlation analysis demonstrated the linking of the alleviation of CDIMS by prebiotics and melatonin with different microbial metabolic pathways involved in energy metabolism, biosynthesis of metabolites, metabolism of cofactors and vitamins and endocrine synthesis., (Copyright © 2021 Elsevier Ltd. All rights reserved.)

β-D-glucans are proposed to have many health benefits. It is therefore important to have methods which can distinguish these from other carbohydrates present in natural products, as well as giving glucan content and structural information. Correlations between features in the CP/MAS spectra of β-D-glucans and enzyme assay determined β-D-glucan content were generally found to be poor. The β-D-glucan in dry and hydrated forms of the mushroom Ganoderma lucidum was investigated in detail by spectral peak fitting to the anomeric carbon C1 region in CP/MAS NMR spectra. Hydrated samples gave spectra with enhanced resolution and suggested that a clear distinction between β-D-glucans and other carbohydrates could be possible in the anomeric carbon C1 region. Chemical shift values for a range of carbohydrate polymers, which can be found alongside β-D-glucans, as well as the values for various linkages are given. Contamination by other carbohydrates and buffer salts is discussed., (Copyright © 2021 Elsevier Ltd. All rights reserved.)

Environmental temperature and pH induced significant changes in the size and surface charge (ζ) of octenylsuccinated oat β-glucan aggregates. The underlying mechanisms were explored by using 1 H-NMR, fluorescence spectra, thermodynamic analysis, and SAXS. At pH 6.5, the size decreased with temperature while ζ continuously increased. With increasing pH at 293 K, parabolic and U-shaped trends were observed in the size and ζ, peaking at pH 8.5 and 6.5, respectively. At any tested pH, the size decreased with temperature. Overall, ζ significantly increased with temperature at each pH. As temperature increased, the compactness of hydrophobic-domains increased while the compactness of hydrophilic-domains decreased. In an acidic environment, both the compactness increased with decreasing pH, but in an alkaline environment, they decreased with pH. The compactness changes were co-driven by enthalpy and entropy and corresponded to changes in the hydrophobic interactions in hydrophobic-domains, hydrogen bonds in hydrophilic-domains and electrostatic repulsions among octenylsuccinate molecules., Competing Interests: Declaration of Competing Interest The authors declare no competing financial interest., (Copyright © 2020 Elsevier Ltd. All rights reserved.)

Foods rich in cereal β-glucan are efficient dietary tools to help reduce serum cholesterol levels and hence the risk of cardiovascular diseases. However, β-glucan undergoes various reactions during food processing, which alter its viscous properties and interactions with components of the gastrointestinal tract. It has been proposed in the literature that oxidation and partial hydrolysis increase β-glucan's bile acid-binding activity, and therefore its effectiveness in lowering cholesterol. Here, the passage kinetics of a bile salt mix across a dialysis membrane was studied with or without oat and barley β-glucan extracts, native or modified (partial hydrolysis and oxidations by sodium periodate or TEMPO (2,2,6,6-tetramethylpiperidine-1-oxyl)). Bile acid-retention turned out to be purely a function of viscosity, with the most viscous native extracts exhibiting the strongest retardation of bile acid permeation. Opposite of what was suggested in the literature, oxidation and molecular weight reduction do not seem to increase the bile acid-binding capability of β-glucan., (Copyright © 2020 Elsevier Ltd. All rights reserved.)

β-carotene has been often used as a hydrophobic nutrient in many functional foods owning to its excellent antioxidant activity. However, the poor orally bioavailability of β-carotene limits its utilization. To overcome such limitation, a delivery system was designed for the encapsulation of β-carotene based on oil-in-water emulsion stabilized by oat protein isolate - Pleurotus ostreatus β-glucan Maillard conjugate. The results showed that such conjugate protected emulsion against environmental stresses by increasing steric and electrostatic repulsion between droplets, mainly manifesting as their smaller particle size and higher surface charge. Additionally, conjugate promoted lipid digestion and formation of mixed micelles, leading to an improved gastrointestinal fate of encapsulated β-carotene, especially for its in vitro bioavailability. Such effects could enhance the cellular antioxidant activity of encapsulated β-carotene in Caco-2 cells. Our findings confirmed that Maillard conjugate can structure an emulsion-based delivery system for the encapsulation of hydrophobic ingredients to improve their utilization., (Copyright © 2019 Elsevier Ltd. All rights reserved.)

In this study, β-glucan was extracted from wholegrain oat and barley flours by a novel extraction and purification method employing natural flocculants (chitosan, guar gum and gelatin). The use of flocculants decreased the total amount of extracted gum, which was highest in control samples (9.07 and 7.9% for oat and barley, respectively). The β-glucan specific yield, however, increased with the use of chitosan and guar gum, which were able to remove protein and ash impurities resulting in gums with a higher purity.The highest concentration of chitosan (0.6 %) resulted in gums with the highest β-glucan content (82.0 ± 0.23 and 79.0 ± 0.19 for barley and oat, respectively) and highest β-glucan specific yield (96.9 and 93.3 % for oat and barley, respectively). Explanation is in R&D section. The use of gelatin was not successful. All gum samples had a high content of total dietary fiber (>74%) and a high water holding capacity (4.6-7.4 g/g), but differed in apparent viscosity, which was highest for the oat sample extracted with 0.6% chitosan. This sample also showed the highest β-glucan molecular weight among the oat samples, which were in general 10-fold higher than for the barley samples. Among the barley samples, β-glucan molecular weight was highest for the control., (Copyright © 2018 Elsevier Ltd. All rights reserved.)

This study investigated the role of phytate in the Fenton reaction induced oxidative degradation of cereal β-glucan. Viscosity analysis showed that the degradation rate was high in the beginning of oxidation, which fitted to the second order kinetic model. Oat β-glucan contained significant amount of residual phytate and after the residual phytate was removed, faster degradation was shown compared to the original oat β-glucan. Adding the same amount of phytic acid (PA) to the phytate removed β-glucan sample also retarded the degradation but not as efficiently as the residual phytate. Considerable retardation of viscosity loss was shown when the PA to iron ratio was high. The presence of ascorbic acid weakened the retardation effect of phytic acid. Thus, phytate can significantly improve the oxidative stability of β-glucan when the ratio of phytic acid to transition metals and the presence of ascorbic acid are taken into consideration., (Copyright © 2017 Elsevier Ltd. All rights reserved.)

In order to improve the emulsifying properties of oat protein, oat protein isolate (OPI)-dextran (Dex) conjugates were prepared by glycation reaction. Emulsifying properties of emulsions stabilized by native OPI (OPIN), OPI-Dex conjugates (ODC) and heated OPI (OPIH) were characterized by zeta-potential, mean droplet size and microstructure. The results showed that the covalent attachment of OPI and dextran was confirmed by determining degree of graft and SDS-PAGE. OPI-Dex conjugates were capable of forming a finer emulsion, which exhibited smaller average particle size and better storage stability under different homogenization pressures (30, 60, 90 MPa) compared with OPIN and OPIH. When assessed in different pH and ionic strength, emulsions stabilized by OPI-Dex conjugates resulted in improved emulsion stability to environmental stresses. Confocal laser scanning microscopy depicted more uniform and smaller oil droplets that had a reduced tendency to coalesce for emulsions prepared with ODC., (Copyright © 2015 Elsevier Ltd. All rights reserved.)

The aim of the present study is to investigate the effects of dietary wheat bran arabinoxylans (AXs) on cholesterol metabolism in hypercholesterolemic hamsters. The hamsters were divided into 3 groups and fed the experimental diets containing AXs or oat β-glucan at a dose of 5 g/kg for 30 days. As the results, the AXs lowered plasma total cholesterol and LDL-cholesterol concentrations, and increased excretions of total lipids, cholesterol and bile acids, as well as oat β-glucan. The AXs reduced the activity of 3-hydroxy-3-methyl glutaryl-coenzyme A (HMG-CoA) reductase, and increased the activity of cholesterol 7-α hydroxylase (CYP7A1) in liver. Moreover, the AXs increased propionate and the total short-chain fatty acids (SCFAs) concentrations. These results indicated that dietary AXs reduced the plasma total cholesterol and LDL-cholesterol concentrations by promoting the excretion of fecal lipids, regulating the activities of HMG-CoA reductase and CYP7A1, and increasing colonic SCFAs in hamsters., (Copyright © 2014 Elsevier Ltd. All rights reserved.)

An enhanced bonding agent for papermaking was prepared by selective oxidation of a hemicellulose-rich byproduct of oat processing, which will be identified here by its primary component, β-D-glucan. The β-D-glucan was treated sequentially with (2,2,6,6-tetramethylpiperidin-1-yl)oxyl (TEMPO) and sodium hypochlorite, or alternatively just with sodium hydroxide. When added to a slurry of unbleached softwood kraft fibers, in combination with an optimal dosage of aluminum sulfate, the oxidized β-D-glucan yielded greater increases in tensile strength and folding endurance in comparison to untreated β-D-glucan. NaOH treatment also improved dry-strength performance of the β-D-glucan, except for folding endurance. The improvements were attributed to increased charge density of the treated polyelectrolytes, leading to better distribution and retention on fibers prior to sheet formation. Modified β-D-glucan also enhanced the strength of recycled sheets when the treated paper was repulped and formed into recycled paper with no further chemical addition., (Copyright © 2013 Elsevier Ltd. All rights reserved.)

Polyacrylamide grafted oatmeal (OAT-g-PAM) was synthesized by conventional method. The grafting of the PAM chains on the biomaterial backbone was confirmed through intrinsic viscosity study, FTIR spectroscopy, elemental analysis (C, H, N, S and O), SEM morphology and TGA study. The intrinsic viscosity of oatmeal appreciably improved on grafting of PAM chains, thus resulting grafted product with potential application as superior viscosifier. Further, flocculation efficacy of the graft copolymer was studied in coal fine suspension, kaolin suspension, iron-ore suspension and then in municipal wastewater through 'jar test' procedure., (Copyright © 2012 Elsevier Ltd. All rights reserved.)

Oat β-glucan was purified from oat bran and its effects on running performance and related biochemical parameters were investigated. Four-week-old male Sparsgue-Dawley rats, fed with/without oat β-glucan (312.5 mg kg(-1) d(-1)) for 7 weeks, were subjected to run on a treadmill system to make them exhausted. All rats were immediately sacrificed after prolonged exercise, and the major metabolic substrates were measured in serum and liver. The results showed feeding dietary oat β-glucan to rats could significantly reduce the body weight and increase the maximum running time compared with normal control (P<0.05). Furthermore, dietary oat β-glucan decreased the levels of blood urea nitrogen, lactate acid, and creatine kinase activity in serum, and increased the levels of non-esterified fatty acids, lactic dehydrogenase activity in serum, and the content of liver glycogen. Therefore, the present study demonstrated that dietary oat β-glucan can enhance the endurance capacity of rats while facilitating their recovery from fatigue., (Copyright © 2012 Elsevier Ltd. All rights reserved.)

In order to understand the relationship between chemical structure and physical properties of cereal β-glucans, the β-glucans with identical Mw (98.4-99.2 kDa) and Rg (21.1-22.0 nm) were isolated from chal and gwangan barley, and ohl oat, and their linkage structure, flow behavior, and thermal properties were investigated. Previously, we established a purification method of 3-O-cellobiosyl-glucose (DP3) and 3-O-cellotriosyl-glucose (DP4) (Yoo, Lee, Chang, Lee, & Yoo, 2007) and applied these authentic standards to quantify the ratio of β-(1,4)/(1,3) linkages in cereal β-glucans. β-Glucans isolated from two barley cultivars had greater proportion of DP3 than did the oat, and within barley cultivars chal barley β-glucan had significantly larger amount of DP3 over gwangan cultivar. Thus, chal barley β-glucan had the greatest molar ratio (2.53) of DP3 to DP4, and ohl oat had the lowest (1.51). While all the β-glucan solutions showed strong shear thinning behavior, ohl oat β-glucan with higher proportion of DP4 exhibited the highest viscosity among the β-glucan samples. After 3 freeze-thaw cycles of 3% (w/v) β-glucan samples, chal barley β-glucan had lower onset (To) and peak (Tp) temperatures (28.3 and 36.7 °C, respectively) than those of gwangan barley (33.6 and 39.9 °C) and ohl oat (37.9 and 46.9 °C) did, and the heat scan profiles were thermoreversible. The To and Tp of inter-chain associations decreased as the DP3:DP4 ratio of the β-glucan increased. From this study, it was suggested that cellotetraosyl units and longer β-(1,4)-linked segments would be a major contributor for improving solution viscosity and gel formation of cereal β-glucans., (Copyright © 2012 Elsevier Ltd. All rights reserved.)