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In this study, a diboronic acid assisted labeling and separation strategy was proposed for the efficient analysis of saccharides in real samples. The diboronic acid was first synthesized and characterized and then used as chemical labels for saccharides through boronate affinity. After labeling, the product was direct submitted to chromatographic analysis. The whole labeling procedure was organic solvent-free and could be accomplished within 1 h. Furthermore, the separation could be realized on the most commonly used chromatographic techniques (RPLC-UV). Taking glucose as an example, the established strategy provided broad linear dynamics ranges (25-5000 ng/mL) with acceptable correlation coefficients (R 2 >0.98), substantial sensitivity (LOD: 5 ng/mL), high reproducibility (RSD<6.7%) and excellent accuracy (Recovery: 98.2-99.8%). Finally, different saccharides were successfully analyzed in various complex samples, from tryptic glycans of glycoproteins to monosaccharides in traditional Chinese medicine., 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 © 2022 Elsevier B.V. All rights reserved.)

The chromatographic response of sugars at granulated zeolite pellets in preparative scale liquid chromatography is analyzed with respect to the distribution equilibrium and mass transfer. In contrast to hydrophilic FAU type zeolites their hydrophobic dealuminated counterpart, used here, can separate disaccharides the retention of which can strongly exceed those of the monosugars. The retention is correlated with data of batch adsorption studies from the literature. Whereas the retention decreases with increasing temperature, the peak sharpness shows the opposite trend. The effective mass resistance is calculated for a series of mono- and disaccharides. It increases with the capacity factor. The diffusion coefficient of the trehalulose disaccharide is restricted by a factor of about 2 in the macropores and by a factor of more than 10 4 in the micropores., (Copyright © 2018 Elsevier B.V. All rights reserved.)

Radix Rehmanniae (RR) is a kind of herb which is widely used in the clinical and food processing industry. There are four forms of RR used in traditional Chinese medicine practice, which include fresh RR (FRR), raw RR (RRR), processed RR (PRR), and another processed RR (APRR), in which the APRR was processed by nine cycles of repeated steaming and drying. There are a large number of saccharides in RR. However, the differences in content were shown by different processing methods. In this study, an effective method using high-performance liquid chromatography (HPLC) and high-performance liquid chromatography-mass spectrometry (LC-MS) coupled with multivariate statistical analysis to rapidly distinguish different RR samples and validate the proposed chemical conversion mechanism. The datasets of the content of saccharides were subjected to principal component analysis (PCA) and one-way analysis of variance. The results showed that there different changes occurred in the contents of saccharides corresponding to the different processing methods, in which the contents of monosaccharides-namely arabinose, glucose, mannose, and galactose-had an increasing trend or remained relatively stable. However, the contents of fructose and oligosaccharides, including manninotriose, melibiose, sucrose, and raffinose, first increased and then reduced, or gradually decreased, yet the content of stachyose gradually decreased. The MS n data indicated that manninotriose, melibiose, and some monosaccharides were produced by the hydrolysis of oligosaccharides. In addition, the fragmentation pathways of 1-phenyl-3-methyl-5-pyrazolone (PMP) derivatization of monosaccharides were also found that its glycosidic bond was first broken and subsequently its inside ring broke, and the characteristic fragment ions were produced at m / z 511.22, 493.20, 373.16, and 175.08 in the PMP derivatization of monosaccharides. In conclusion, this study illustrates the change and chemical conversion mechanism of saccharides by processing in RR samples which might play a key role in further application of RR., Competing Interests: The authors declare no conflict of interest.

Zinc oxide (ZnO) nanoparticles (NPs) are widely used as a Zn supplement, because Zn plays a role in many cellular and immune functions but public concern about their potentially undesirable effects on the human body is growing. When NPs are added in food matrices, interactions between NPs and food components occur, which can affect biological systems. In this study, interactions between ZnO NPs and saccharides were investigated by measuring changes in hydrodynamic radius, zeta potential and solubility and by quantifying amounts of adsorbed saccharides on NPs; acacia honey, sugar mixtures (containing equivalent amounts of fructose, glucose, sucrose and maltose) and monosaccharide solutions were used as model compounds. Biological responses of NPs dispersed in different saccharides were also evaluated in human intestinal cells and rats in terms of cytotoxicity, cellular uptake, intestinal transport and oral absorption. The results demonstrate that the hydrodynamic radii and zeta potentials of NPs were highly affected by saccharides. In addition, trace nutrients influenced NP/saccharide interactions and interactive effects between saccharides on the interactions were found. NPs in all saccharides increased inhibition of cell proliferation and enhanced cellular uptake. Oral absorption of NPs was highly enhanced by 5% glucose, which is in-line with intestinal transport result. These findings show that ZnO NPs interact with saccharides and these interactions affects biological responses., Competing Interests: The authors declare no conflict of interest. The founding sponsors had no role in the design of the study; in the collection, analyses, or interpretation of data; in the writing of the manuscript and in the decision to publish the results.

Glycine receptors (GlyRs) mediate fast synaptic inhibition in spinal cord, brainstem, and higher brain centers. Recently, glucose was identified as a positive modulator of GlyR-mediated currents. Here, we investigated extent and kinetics of the positive modulation of recombinant human α1 glycine receptors by different mono- and disaccharides and sorbitol using patch-clamp recording techniques. Glucose and fructose augmented glycine-mediated whole-cell currents with an EC50 of 6-7 mM. At concentrations > 10 mM, the maximum of current enhancement was reached within ∼30 min. Kinetics of GlyR modulation resemble those of protein glycation. On-rates were <0.5 h for saturating concentrations of monosaccharides and ∼1.5 h for disaccharides. Off-rates were considerably slower (>24 h). Galactose, the C4-epimer of glucose, and the sugar alcohol sorbitol had no effect on GlyR currents. Recent cryoelectron microscopy structures were used to identify a potential binding site for saccharides near the ivermectin binding pocket with lysine 143 as possible attachment site. The GlyR mutant α1(K143A) was not potentiated by glucose, suggesting an involvement of this residue in glycine receptor modulation by saccharides.

Terahertz time-domain attenuated total reflection measurements of monosaccharide (glucose and fructose) and disaccharide (sucrose and trehalose) solutions from 0.146 M to 1.462 M were performed to evaluate (1) the hydration state and (2) the destructuring effect of saccharide solutes on the hydrogen bond (HB) network. Firstly, the extent of hydration water was determined by the decreased amount of bulk water with picosecond relaxation time that was replaced by that with much longer orientational relaxation time. As a result, we found glucose and trehalose exhibits stronger hydration capacity than fructose and sucrose, respectively, despite of the same number of the hydroxyl groups. For each saccharide, the hydration number tended to decrease with solute concentration. Secondly, the destructuring effect of these saccharide solutes on the HB network of the surrounding bulk water was discussed from the perspective of the fraction of non-hydrogen-bonded (NHB) water isolated from the HB network. We found the fraction of NHB water molecules that are not engaged in the HB network monotonously increased with saccharide concentration, indicating saccharide solutes promote the disruption of the water HB network. However, no noticeable differences were confirmed in the fraction of NHB water between glucose and fructose or between sucrose and trehalose. In contrast to hydration number, the number of NHB water produced by a single saccharide solute was less dependent on solute concentration, and three monosaccharide/disaccharide solutes were found to produce one/two NHB water molecules., (Copyright © 2015 Elsevier Ltd. All rights reserved.)

Herein, a three-dimensional carbohydrate modified polyacrylamide hydrogel microarray (3D carbohydrate hydrogel microarray) has been fabricated and employed as micro-reactor for capturing Escherichia coli (E. coli) by multivalent binding of concanavalin A (Con A) with O-antigen on the cellular surface of E. coli and immobilized monosaccharides on hydrogel spot, and the interactions of type 1 fimbriae of E. coli with immobilized monosaccharides. Because of the transparent performance of polyacrylamide hydrogel, the captured E. coli can be directly observed by a conventional microscope under a bright-field mode. The experimental result demonstrates that α-D-mannopyranoside (Man-α) modified hydrogel surface shows high efficiency of E. coli capturing. The 3D Man-α hydrogel microarray-based assay shows reasonable low detection limit (1.0×10(4) cells/mL) and large dynamic range (1.0×10(5) to 1.0×10(9)cells/mL) for detecting E. coli. In addition, bacterial adhesion inhibition assay has been demonstrated by the interactions of E. coli with ten saccharides, and satisfactory results have been obtained., (Copyright © 2014 Elsevier B.V. All rights reserved.)

Conversion of hemicellulose streams and the constituent monosaccharides, xylose, arabinose, glucose, mannose, and galactose, was conducted to produce value‐added chemicals, including furfural, hydroxymethylfurfural (HMF), levulinic acid and anhydrosugars. The study aimed at developing a kinetic model relevant for direct post‐Organosolv hemicellulose conversion. Monosaccharides served as a tool to in detail describe the kinetic behavior and segregate contribution of hydrothermal decomposition and acid catalyzed dehydration at the temperature range of 120–190 °C. Catalyst free aqueous media demonstrated enhanced formation of furanics, while elevated temperatures led to significant saccharide isomerization. The introduction of sulfuric and formic acids maximized furfural yield and significantly reduced HMF concentration by facilitating its rehydration into levulinic acid (46 mol%). Formic acid additionally substantially enhanced formation of anhydrosaccharides. An excellent correlation between modeled and experimental data enabled process optimization to maximize furanic yield in two distinct hemicellulose streams. Sulfuric acid‐containing hemicellulose stream achieved the highest furfural yield after 30 minutes at 238 °C, primarily due to the high Ea for pentose dehydration (150–160 kJ mol−1). Contrarily, formic acid‐containing hemicellulose stream enabled maximal furfural yield at more moderate temperature and extended reaction time due to its lower Ea for the same reaction step (115–125 kJ mol−1). [ABSTRACT FROM AUTHOR]

To date, humans are looking for suitable energy sources to meet the global demand for fuels. Among many candidates, biohydrogen (bio‐H2), a future fuel perspective, is expected to grow critically and receive considerable attention to replace fossil fuels. This review focuses on biohydrogen production via post‐method photocatalytic reforming of ideal feedstock and abundant lignocellulosic biomass. Renewable biomass precursors are used without net greenhouse gas emissions. This idea holds great promise as a sustainable and environmentally friendly energy solution. In particular, many saccharide substrates, including monosaccharides, disaccharides, polysaccharides, etc., have been used as sacrificial reagents in photocatalytic reforming over the past few decades. Among the various substrates, cellulose has attracted worldwide attention since it is the most abundant polymeric biomass resource that can be obtained from many sources. Following, photo‐reforming of renewable lignocellulosic biomass, which aligns with the requirements of sustainable development, is successfully proposed. The overall catalytic efficiency will be discussed regarding the biohydrogen evolution rate (mmol gcat−1 h−1). Finally, the review concluded with challenges and potential opportunities to enhance biohydrogen are also given. [ABSTRACT FROM AUTHOR]

Saccharides, being one of the fundamental molecules of life, play essential roles in the physiological and pathological functions of cells. However, their intricate structures pose challenges for detection. Nanopore technology, with its high sensitivity and capability for single-molecule-level analysis, has revolutionized the identification and structural analysis of saccharide molecules. This review focuses on recent advancements in nanopore technology for carbohydrate detection, presenting an array of methods that leverage the molecular complexity of saccharides. Biological nanopore techniques utilize specific protein binding or pore modifications to trigger typical resistive pulses, enabling the high-sensitivity detection of monosaccharides and oligosaccharides. In solid-state nanopore sensing, boronic acid modification and pH gating mechanisms are employed for the specific recognition and quantitative analysis of polysaccharides. The integration of artificial intelligence algorithms can further enhance the accuracy and reliability of analyses. Serving as a crucial tool in carbohydrate detection, we foresee significant potential in the application of nanopore technology for the detection of carbohydrate molecules in disease diagnosis, drug screening, and biosensing, fostering innovative progress in related research domains. [ABSTRACT FROM AUTHOR]

Selective acylation of saccharides is an important basic transformation in saccharide chemistry. Synthetic strategies and protocols for saccharides can reach broad users when reagents are simple (inexpensive and readily available), green, and easy to handle. Herein, we disclose that the simplest boric acid, B(OH)3, can work as an effective promoter for C3–OH selective acylation of unprotected monosaccharides under the catalysis of a readily available N-heterocyclic carbene catalyst. Solvents such as THF from untreated commercial sources can be directly used. Mechanistically, the boric acid plays multiple roles in benefiting reaction yields and regioselectivities, including solubilizing the saccharide substrates by forming borate esters with the saccharides, shielding the C6–OH unit of the saccharides from acylation, and enhancing the selectivity between C3–OH and C2–OH reactions. We also found that the solvent has a profounder effect on the reaction yield and selectivity than the base. Selectively acylated saccharide products can be easily obtained with good-to-excellent yields and gram scales. Our study will encourage the further development of new synthetic strategies for saccharides that can reach beyond laboratory scales and to scientists not necessarily with expertise in organic synthesis. Compared to previous methods using aryl and alkyl boronic acids as modulating reagents, the use of boric acid provides a greener solution economically and environmentally. [ABSTRACT FROM AUTHOR]

The aim of this study was to determine the changes occurring in the wood cellulose of the fast-growing poplar (Populus deltoides × maximowiczii) under the influence of steam explosion (SE) pretreatment. Cellulose from native wood and after pretreatment at 160 and 205 °C was isolated. Cellulose polymerization degree by size exclusion chromatography (SEC) and cellulose crystallinity index by Fourier transform infrared spectroscopy-attenuated total reflectance (FTIR-ATR) were determined. The profiles of sugars in the native wood and in the solid fraction after pretreatment (using the acid hydrolysis method) were also determined. In addition, the profile of monosaccharides in the liquid fraction obtained after steam explosion and in the liquid fraction after acid hydrolysis of the oligosaccharides were investigated using high-performance liquid chromatography (HPLC). This allowed to determine the change in the yield of hexoses and pentoses in the studied material. The behavior of cellulose in wood subjected to steam explosion at 160 and 205 °C and isolated by the Kürschner–Hoffer method was studied by determining the absorption bands of FTIR-ATR spectra. The lateral order index (LOI) of cellulose was calculated from the ratio of the intensity of the corresponding absorption bands A1422/A896 cm−1. Total crystallinity index (TCI) of cellulose was calculated from the ratio of the intensity of absorption bands A1372/A2900 cm−1. TCI of Kürschner-Hoffer cellulose isolated from wood subjected to steam explosion at 160 and 205 °C decreased by 5.6 and 5.0%, respectively, with regard to the applied temperature. LOI increased in cellulose isolated from wood subjected to steam explosion at 160 °C (by 0.7%) and at 205 °C (by 19.2%) in relation to the index of cellulose isolated from native wood. Kürschner–Hoffer cellulose isolated from wood subjected to steam explosion at 160 and 205 °C exhibited, respectively, a reduced degree of polymerization of about 11% and about 8%. Polydispersity index in Kürschner–Hoffer cellulose was 1% lower after both pretreatments than native sample. [ABSTRACT FROM AUTHOR]

Disaccharides are composed of two monosaccharide subunits joined by a glycosidic linkage in an α or β configuration. Different combinations of isomeric monosaccharide subunits and different glycosidic linkages result in different isomeric disaccharide products. Thus, direct discrimination of these disaccharide isomers from a mixture is extremely difficult. In this paper, a hetero‐octameric Mycobacterium smegmatis porin A (MspA) nanopore conjugated with a phenylboronic acid (PBA) adapter was applied for disaccharide sensing, with which three most widely known disaccharides in nature, including sucrose, lactose and maltose, were clearly discriminated. Besides, all six isomeric α‐D‐glucopyranosyl‐D‐fructoses, differing only in their glycosidic linkages, were also well resolved. Assisted by a custom machine learning algorithm, a 0.99 discrimination accuracy is achieved. Nanopore discrimination of disaccharide isomers with different glycosidic linkages, which has never been previously demonstrated, is inspiring for nanopore saccharide sequencing. This sensing capacity was also applied in direct identification of isomaltulose additives in a commercial sucrose‐free yogurt, from which isomaltulose, lactose and L‐lactic acid were simultaneously detected. [ABSTRACT FROM AUTHOR]

Liquid is a promising candidate for terahertz radiation induced by femtosecond laser pulses, since it has advantages of higher molecular density, lower ionization potential and better self-healing properties compared with gases. In this work, an enhancement of terahertz radiation from saccharide solutions induced by femtosecond laser pulses is demonstrated, and the characteristics of terahertz radiation from saccharide solutions of different types and concentrations are investigated. It shows that terahertz radiant power from a glucose solution is 2 times higher than that from liquid water under the same excitation conditions. Among all the saccharide solutions studied, polysaccharides radiate the most powerful terahertz pulses and monosaccharides show the weakest radiation. The optimal solution concentrations of polysaccharide and disaccharide for terahertz radiation are 5 and 30%, respectively. As for monosaccharide solutions, when the concentration of the solution increases in the range of 0–30%, the power of terahertz radiation increases. In addition, quantum chemical calculations are carried out in this study to help explain the mechanisms for terahertz radiation from saccharide solutions. It is demonstrated that the power of terahertz radiation from saccharide solutions is roughly positively correlated with molecular qualities, densities, and viscosities of saccharide solutions, while negatively correlated with the band gap. [ABSTRACT FROM AUTHOR]

This article highlights the fundamental aspects of hydrophilic interaction liquid chromatography (HILIC) on poly-hydroxyl stationary phases to analyze non-derivatized mono- and disaccharides, including commonly consumed carbohydrates like glucose, fructose, sucrose, and lactose. The evaporative light-scattering detector (ELSD) is utilized as an alternative to an MS detector, and the separation system's selectivity allows the separation of anomers of monosaccharides. The study also includes a rapid method for determining isomaltulose (Palatinose), which was validated and applied to food supplement samples available in the Czech market, even those with high protein content. Additionally, isomaltulose was separated from sucrose in just 13 min. [ABSTRACT FROM AUTHOR]

Simultaneous chromatographic separation of the anomers of saccharides was achieved by using a polymer zwitterionic stationary phase functionalized by acrylamide‐type sulfobetaine. By optimization of separation parameters including column temperature, pH, and flow rate, the column operated in hydrophilic interaction chromatography mode exhibited excellent separation selectivity toward five monosaccharides and their anomers (including ribose, xylose, galactose, glucose, and arabinose) and two disaccharides (lactose and maltose). Baseline separation could be achieved at mild operation conditions such as 20–30°C of column temperature or typical mobile phase composition (85% acetrontrile–15% 20 mM ammonium formate [NH4FA]) with wide pH tolerance range of 2–8. This offers a rapid way to determine the configuration of α or β anomer of the saccharides. [ABSTRACT FROM AUTHOR]

One‐pot multiple tandem synthesis of DMF from biomass saccharides including monosaccharides, disaccharides, and polysaccharides is of great importance for biomass fuels and chemicals. Due to the complexity of reactions, current catalytic systems often suffer from inferior activity, low yield, and harsh reaction conditions. Here, a Pd‐supported hydrophobic acidic 2DMOF (Pd/NUS‐PhSO3H‐Ph) was first prepared by continuous grafting of benzenesulfonic acid and tert‐butylbenzene groups followed by Pd impregnation methods. It shows catalytic efficiency for the DMF synthesis from saccharides under the reduction of polymethylhydrosiloxane (PMHS), which are previously unattainable in all reported catalysts. Controlled experiments and detailed characterizations show that hydrophobic 2D nanosheet structure promotes the wettability of feedstocks and intermediates for the active sites. This work proposes a new door toward an efficient and facile synthesis of DMF via designing a powerful 2DMOF‐based catalyst with cooperative acid‐hydrogenation catalysis. [ABSTRACT FROM AUTHOR]

In the present study, an attempt was made to investigate the in vitro antioxidant, anticancer, and antibacterial activities of Delonix regia, then in vivo evaluate its safety as a natural colorant and sweetener in beverages compared to synthetic colorant and sweetener in rats, then serve the beverages for sensory evaluation. Delonix regia flowers had high protein, polysaccharide, Ca, Na, Mg, K, and Fe contents. The Delonix regia pigment extract (DRPE) polysaccharides were separated and purified by gel permeation chromatography on Sephacryl S-200, characterized by rich polysaccharides (13.6 g/L). The HPLC sugar profile detected the monosaccharides in the extracted polysaccharides, composed of mannose, galactose, glucose, arabinose, and gluconic acid, and the structure of saccharides was confirmed by FTIR, which showed three active groups: carbonyl, hydrocarbon, and hydroxyl. On the other hand, the red pigment constituents of DRPE were detected by HPLC; the main compounds were delphinidin and cyanidin at 15 µg/mL. The DRPE contained a considerable amount (26.33 mg/g) of anthocyanins, phenolic compounds (64.7 mg/g), and flavonoids (10.30 mg/g), thus influencing the antioxidant activity of the DRPE, which scavenged 92% of DPPH free radicals. Additionally, it inhibited the population of pathogenic bacteria, including Staphylococcus aureus, Listeria monocyogenes, Salmonella typhimurum, and Pseudomonas aeruginosa, in the range of 30–90 μg/mL, in addition to inhibiting 85% of pancreatic cancer cell lines. On the in vivo level, the rats that were delivered a diet containing DRPE showed regular liver markers (AST, ALP, and ALT); kidney markers (urea and creatinine); high TP, TA, and GSH; and low MDA, while rats treated with synthetic dye and aspartame showed higher liver and kidney markers; lowered TP, TA, and GSH; and high MDA. After proving the safety of DRPE, it can be safely added to strawberry beverages. Significant sensorial traits, enhanced red color, and taste characterize the strawberry beverages supplemented with DRPE. The lightness and redness of strawberries were enhanced, and the color change ΔE values in DRPE-supplemented beverages ranged from 1.1 to 1.35 compared to 1.69 in controls, indicating the preservative role of DRPE on color. So, including DRPE in food formulation as a natural colorant and sweetener is recommended for preserving health and the environment. [ABSTRACT FROM AUTHOR]

Aluminum (Al) toxicity is the primary factor limiting agricultural productivity in acid soils. The cell wall is mainly composed of saccharides and the first barrier for aluminum (Al) to enter plant root cells, but it is unknown whether and how root saccharide components are involved in regulating the Al tolerance of Lespedeza that is well adapted to acid soils. Here, we used Al-tolerant Lespedeza bicolor and Al-sensitive Lespedeza cuneata to examine the association of root saccharide components with Lespedeza Al tolerance through analyzing the saccharide changes of roots exposed to Al toxicity. Al-sensitive Lespedeza accumulated more Al and pectin but less hemicellulose in the root cell walls than Al-tolerant Lespedeza. Al treatment decreased the amounts of total sugar secreted from and within the roots of only Al-tolerant Lespedeza. Al treatment decreased the content of root monosaccharides including glucose and mannose in both Lespedeza species, but increased the xylose contents in only Al-sensitive Lespedeza. Taken together, less cell wall pectin rather than hemicellulose is responsible for less root Al accumulation, and Al-decreased root saccharide contents may enhance root organic-acid secretion to chelate toxic Al, both of which contribute to Lespedeza Al tolerance. [ABSTRACT FROM AUTHOR]

Traditional Chinese medicine (TCM) safety and effectiveness can be ensured by establishing a suitable quality assessment system. This work aims to develop a pre-column derivatization HPLC method for Polygonatum cyrtonema Hua. quality control. In this study, 1-(4′-cyanophenyl)-3-methyl-5-pyrazolone (CPMP) was synthesized and reacted with monosaccharides derived from P. cyrtonema polysaccharides (PCPs), followed by HPLC separation. According to the Lambert–Beer law, CPMP has the highest molar extinction coefficient of all synthetic chemosensors. A satisfactory separation effect was obtained under a detection wavelength of 278 nm using a carbon-8 column and gradient elution over 14 min, with a flow rate of 1 mL per minute. Glucose (Glc), galactose (Gal), and mannose (Man) make up the majority of the monosaccharide components in PCPs, and their molar ratios are 1.73:0.58:1. The confirmed HPLC method has outstanding precision and accuracy, establishing a quality control method for PCPs. Additionally, the CPMP showed a visual improvement from colorless to orange after the detection of reducing sugars, allowing for further visual analysis. [ABSTRACT FROM AUTHOR]

Environmental context: Saccharides contribute substantially to dissolved organic carbon in the ocean and are enriched at the ocean surface. In this study, we demonstrate that saccharides are more enriched in persistent whitecap foam compared to the sea surface. The maturation of bubbles at the air–water interface is thus expected to enhance the enrichment of organic matter at the ocean surface and ultimately in the sea spray aerosol that forms when bubbles burst at the ocean surface. Rationale: Organic matter accumulates at the ocean surface. Herein, we provide the first quantitative assessment of the enrichment of dissolved saccharides in persistent whitecap foam and compare this enrichment to the sea surface microlayer (SSML) during a 9 day mesocosm experiment involving a phytoplankton bloom generated in a Marine Aerosol Reference Tank (MART). Methodology: Free monosaccharides were quantified directly, total saccharides were determined following mild acid hydrolysis and the oligo/polysaccharide component was determined as the difference between total and free monosaccharides. Results: Total saccharides contributed a significant fraction of dissolved organic carbon (DOC), accounting for 13% of DOC in seawater, 27% in SSML and 31% in foam. Median enrichment factors (EFs), calculated as the ratio of the concentrations of saccharides relative to sodium in SSML or foam to that of seawater, ranged from 1.7 to 6.4 in SSML and 2.1–12.1 in foam. Based on median EFs, xylitol, mannitol, glucose, galactose, mannose, xylose, fucose, rhamnose and ribose were more enriched in foam than SSML. Discussion: The greatest EFs for saccharides coincided with high chlorophyll levels, indicating increasing ocean surface enrichment of saccharides during phytoplankton blooms. Higher enrichments of organic matter in sea foam over the SSML indicate that surface active organic compounds become increasingly enriched on persistent bubble film surfaces. These findings help to explain how marine organic matter becomes highly enriched in sea spray aerosol that is generated by bursting bubbles at the ocean surface. Environmental context. Saccharides contribute substantially to dissolved organic carbon in the ocean and are enriched at the ocean surface. In this study, we demonstrate that saccharides are more enriched in persistent whitecap foam compared to the sea surface. The maturation of bubbles at the air–water interface is thus expected to enhance the enrichment of organic matter at the ocean surface and ultimately in the sea spray aerosol that forms when bubbles burst at the ocean surface. [ABSTRACT FROM AUTHOR]

The anti-cancer effects of selenylated plant polysaccharides are a focus of research. As a natural plant with extensive biological effects, there have been few studies related to edible purslane (Portulaca oleracea L.). Thus, in this study, soluble P. oleracea polysaccharides (PPS) were extracted from the dried P. oleracea and then selenylated chemically using the HNO3-Na2SeO3 method to obtain two selenylated products, namely, SePPS1 and SePPS2. Compared with the extracted PPS, SePPS1 and SePPS2 had much higher Se contents (840.3 and 1770.5 versus 66.0 mg/kg) while also showing lower contents in three saccharides—arabinose, fucose, and ribose—and higher contents in seven saccharides including galactose, glucose, fructose, mannose, rhamnose, galacturonic acid, and glucuronic acid, but a stable xylose content demonstrated that the performed chemical selenylation of PPS led to changes in monosaccharide composition. Moreover, SePPS1 and SePPS2 shared similar features with respect to monosaccharide composition and possessed higher bioactivity than PPS in human colon cancer HCT-116 cells. Generally, SePPS1 and SePPS2 were more active than PPS with respect to cell growth inhibition, the alteration of cell morphology, disruption of mitochondrial membrane potential, intracellular reactive oxygen species (ROS) generation, the induction of cell apoptosis, and upregulation or downregulation of five apoptosis-related genes and proteins such as Bax, Bcl-2, caspases-3/-9, and cytochrome C, that cause cell apoptosis and growth suppression via the ROS-mediated mitochondrial pathway. SePPS2 consistently showed the highest capacity to exert these observed effects on the targeted cells, suggesting that the performed chemical selenylation of PPS (in particular when higher degrees of selenylation are reached) resulted in an increase in activity in the cells. It can thus be concluded that the performed selenylation of PPS was able to incorporate inorganic Se into the final PPS products, changing their monosaccharide composition and endowing them with enhanced nutraceutical and anti-cancer effects in the colon. [ABSTRACT FROM AUTHOR]

Dehydration of the most relevant biomass derived monosaccharides, xylose, glucose and fructose, was investigated to attain value-added platform chemicals: furfural, hydroxymethylfurfural (5-HMF) and levulinic acid (LA). Reaction kinetics were studied in an aqueous environment in the presence and absence of the H-BEA zeolite. H-BEA demonstrated high activity, especially for isomerization of monosaccharides and rehydration of 5-HMF, while this work demonstrated that dehydration of sugars was governed predominantly by homogeneous reactions. Saccharide reactivity followed the trend of fructose > xylose > glucose, while 5-HMF was more susceptible to further conversion compared to furfural. The addition of H-BEA compromised 5-HMF yields (being an intermediate), and facilitated its further conversion to levulinic acid. The absence of a solid acid catalyst resulted in significant amounts of furfural and 5-HMF, whereas the addition of H-BEA resulted in higher yields of levulinic acid (26 mol% and 30 mol%). Excellent agreement between experimental and modelled values allowed the use of kinetic parameters for predictive modelling and optimization of the process conditions for maximizing the yields of 5-HMF and LA. The optimization was experimentally validated, where homogeneously catalyzed dehydration of fructose resulted in the highest 5-HMF yield (52 mol%) attained in 34 min at 234 °C due to the high activation energy (139 kJ mol−1) and reaction rate constants. In contrast, the highest LA yield was achieved at moderate operational temperatures (165 °C) and longer reaction times (10 h) as a result of a significantly lower energy barrier (60 kJ mol−1) determined for rehydration reactions. [ABSTRACT FROM AUTHOR]

Miscanthus × giganteus samples were characterized for composition and treated with hot compressed water (hydrothermal or autohydrolysis treatments) at temperatures in the range of 190–240 °C. The liquid phases from treatments were analyzed to assess the breakdown of susceptible polysaccharides into a scope of soluble intermediates and reaction products. The experimental concentration profiles determined for the target compounds (monosaccharides, higher saccharides, acetic acid and sugar-decomposition products) were interpreted using a pseudohomogeneous kinetic mechanism involving 27 reactions, which were governed by kinetic coefficients showing an Arrhenius-type temperature dependence. The corresponding activation energies were calculated and compared with data from the literature. The kinetic equations allowed a quantitative assessment of the experimental results, providing key information for process simulation and evaluation. [ABSTRACT FROM AUTHOR]

Ultra-high performance liquid chromatography-quadrupole-time of flight tandem mass spectrometry (UHPLC-Q-TOF-MS/MS) was used to study the diversity of tea polysaccharides and the dynamic changes in the physicochemical indexes of tea samples. FT-IR spectra and the free radical scavenging ability of tea polysaccharides, during pile-fermentation of post-fermented tea, were analyzed. The results showed that 23 saccharide co mponents in tea polysaccharides were identified: these belonged to 11 monosaccharides, 5 oligosaccharides, and 6 derivatives of monosaccharides and oligosaccharides. The abundance of oligosaccharides decreased gradually, while monosaccharides, and derivatives of monosaccharides and oligosaccharides increased gradually with the development of pile-fermentation. According to the differences in polysaccharide composition and their abundance, the tea polysaccharide samples extracted from different pile-fermentation stages could be clearly classed into three groups, W-0, W-1~W-4 and W-5~C-1. The pile-fermentation process affected the yield, the content of each component, FT-IR spectra, and the DPPH free radical scavenging ability of tea polysaccharides. Correlation analysis showed that microorganisms were directly related to the changes in composition and the abundance of polysaccharides extracted from different pile-fermentation stages. The study will further help to reveal the function of tea polysaccharides and promote their practical application as a functional food. [ABSTRACT FROM AUTHOR]

Saccharides play critical roles in many forms of cellular activities. Saccharide structures are however complicated and similar, setting a technical hurdle for direct identification. Nanopores, which are emerging single molecule tools sensitive to minor structural differences between analytes, can be engineered to identity saccharides. A hetero‐octameric Mycobacterium smegmatis porin A nanopore containing a phenylboronic acid was prepared, and was able to clearly identify nine monosaccharide types, including D‐fructose, D‐galactose, D‐mannose, D‐glucose, L‐sorbose, D‐ribose, D‐xylose, L‐rhamnose and N‐acetyl‐D‐galactosamine. Minor structural differences between saccharide epimers can also be distinguished. To assist automatic event classification, a machine learning algorithm was developed, with which a general accuracy score of 0.96 was achieved. This sensing strategy is generally suitable for other saccharide types and may bring new insights to nanopore saccharide sequencing. [ABSTRACT FROM AUTHOR]

The detection and quantification of glucose concentrations in human blood or in the ocular fluid gain importance due to the increasing number of diabetes patients. A reliable determination of these low concentrations is hindered by the complex aqueous environments in which various biomolecules are present. In this study, we push the detection limit as well as the discriminative power of plasmonic nanoantenna-based sensors towards the physiological limit. We utilize plasmonic surface-enhanced infrared absorption spectroscopy (SEIRA) to study aqueous solutions of mixtures of up to five different physiologically relevant saccharides, namely the monosaccharides glucose, fructose, and galactose, as well as the disaccharides maltose and lactose. Resonantly tuned plasmonic nanoantennas in a reflection flow cell geometry allow us to enhance the specific vibrational fingerprints of the mono- and disaccharides. The obtained spectra are analyzed via principal component analysis (PCA) using a machine learning algorithm. The high performance of the sensor together with the strength of PCA allows us to detect concentrations of aqueous mono- and disaccharides solutions down to the physiological levels of 1 g/L. Furthermore, we demonstrate the reliable discrimination of the saccharide concentrations, as well as compositions in mixed solutions, which contain all five mono- and disaccharides simultaneously. These results underline the excellent discriminative power of plasmonic SEIRA spectroscopy in combination with the PCA. This unique combination and the insights gained will improve the detection of biomolecules in different complex environments. [ABSTRACT FROM AUTHOR]

[Display omitted] • Steam explosion of Eucalyptus globulus to produce hydrolysates containing XOS. • Membranes of 750 and 200 Da allowed the removal of degradation products from XOS. • The separation mechanism for saccharides and furans was primarily molecular sieving. • Donnan exclusion played a key role in the retention of glucuronic acid. • Permeability loss during nanofiltration was fully restored after cleaning-in-place. Nanofiltration was applied to purify steam explosion hydrolysates obtained from Eucalyptus globulus woodchips. The complex hydrolysate comprised xylooligosaccharides, monosaccharides, glucuronic acid (GluA), and degradation products, including acetic acid, furfural, and 5-hydroxymethylfurfural (HMF). Membranes with 750 and 200 Da molecular weight cut-offs were assessed for their ability to retain oligosaccharides while allowing degradation products to permeate. Using the 750 Da membrane, the average compound retention order was: acetic acid (9.8 %) < furfural (10.8 %) < HMF (31.4 %) ≪ arabinose (52.5 %) < xylose (63.8 %) < glucose (76.0 %) < GluA (90.6 %). The separation mechanism for neutral saccharides and furans was primarily molecular sieving, while Donnan exclusion was the primary retention mechanism responsible for GluA. Separation factors obtained for acetic acid and furfural over xylotriose and xylobiose exceeded 10 and 3, respectively, for both membranes, showing that desired compounds were predominantly retained. Permeability loss during nanofiltration was fully restored after implementing cleaning-in-place for both membranes. [ABSTRACT FROM AUTHOR]

Rationale: Sugars are key molecules of life but challenging to detect via electrospray ionization mass spectrometry (ESI‐MS). Unfortunately, sugars are challenging analytes for mass spectrometric methods due to their high gas‐phase deprotonation energies and low gas‐phase proton affinities which make them difficult to ionize in high abundance for MS detection. Methods: Hydrogen‐bond interactions in H2PO4−–saccharide anionic systems were studied both experimentally (via electrospray ionization Fourier transform ion cyclotron resonance mass spectrometry, ESI‐FT‐ICR‐MS) and computationally by several sophisticated density‐functional theoretical methods (DFT and DFT‐D3). Results: The H2PO4− dopant boosts the detection of sugars up to 51‐times in the case of sucrose and up to 263‐times for glucose (at 0.1 ppm concentration level). H2PO4− binds toward sugar molecules with noticeably more hydrogen bonds than the established dopant chloride Cl− does, with increasing binding energies in the order: Monosaccharides < Trisaccharides < Disaccharides. Analysis of a complex oak plant sample revealed that NH4H2PO4 specifically labeled a diverse set of sugar‐type plant metabolites in the form of [M + H2PO4]− complexes. Conclusions: We reveal the mechanism of interaction of H2PO4− with different sugars and glycosylated organic compounds, which significantly enhances their ionization in mass spectrometry. A computational and experimental investigation is presented. A strong correlation between the MS signal intensities of detected [M + H2PO4]− anions of different saccharides and their calculated dissociation enthalpies was revealed. Thus, the variation in MS signal intensities can be very well described to a large extent by the variation in calculated saccharide affinities toward the H2PO4− dopant anion, showing that DFT‐D3 can very well describe experimental FT‐ICR‐MS observations. [ABSTRACT FROM AUTHOR]

Simple Summary: All livings are composed of cells, which contain lipid, proteins, nuclei acids, and saccharides. Saccharides include polysaccharides, oligo saccharides, disaccharides, which are linked by monosaccharides. Monosaccharides such as glucose exist in two forms, named α and β anomer, in solution. In addition, monosaccharides could be linked with lipid, proteins, nuclei acids or other saccharide to form glycosides through glycosylation. In nature, glycosylation is catalyzed by enzymes. Until now, all enzymes catalyzed glycosylation to form glycosides with either α or β form but not both. This study found an enzyme, amylosucrase from Deinococcus geothermalis (DgAS), could catalyze glycosylation of a kind of lipid named ganoderic acids triterpenoids from a medicinal fungus Ganoderma lucidum to form both α and β anomer of glycosides. This is the first report that enzymes could catalyze such glycosylation and a possible reaction mechanism was proposed. Glycosylation occurring at either lipids, proteins, or sugars plays important roles in many biological systems. In nature, enzymatic glycosylation is the formation of a glycosidic bond between the anomeric carbon of the donor sugar and the functional group of the sugar acceptor. This study found novel glycoside anomers without an anomeric carbon linkage of the sugar donor. A glycoside hydrolase (GH) enzyme, amylosucrase from Deinococcus geothermalis (DgAS), was evaluated to glycosylate ganoderic acid F (GAF), a lanostane triterpenoid from medicinal fungus Ganoderma lucidum, at different pH levels. The results showed that GAF was glycosylated by DgAS at acidic conditions pH 5 and pH 6, whereas the activity dramatically decreased to be undetectable at pH 7 or pH 8. The biotransformation product was purified by preparative high-performance liquid chromatography and identified as unusual α-glucosyl-(2→26)-GAF and β-glucosyl-(2→26)-GAF anomers by mass and nucleic magnetic resonance (NMR) spectroscopy. We further used DgAS to catalyze another six triterpenoids. Under the acidic conditions, two of six compounds, ganoderic acid A (GAA) and ganoderic acid G (GAG), could be converted to α–glucosyl-(2→26)-GAA and β–glucosyl-(2→26)-GAA anomers and α-glucosyl-(2→26)-GAG and β-glucosyl-(2→26)-GAG anomers, respectively. The glycosylation of triterpenoid aglycones was first confirmed to be converted via a GH enzyme, DgAS. The novel enzymatic glycosylation-formed glycoside anomers opens a new bioreaction in the pharmaceutical industry and in the biotechnology sector. [ABSTRACT FROM AUTHOR]

This work presents a comparative study for the analysis of carbohydrates for four common chromatographic methods, each coupled to mass spectrometry. Supercritical fluid chromatography (SFC), hydrophilic interaction liquid chromatography (HILIC), reversed-phase liquid chromatography (RP-LC) and gas chromatography (GC) with detection by triple quadrupole mass spectrometer (QqQ-MS) are compared. It is shown that gas chromatography and reversed-phase liquid chromatography, each after derivatisation, are superior to the other two methods in terms of separation performance. Furthermore, comparing the different working modes of the mass spectrometer, it can be determined that a targeted analysis, i.e. moving from full scan to single ion monitoring (SIM) and multiple reaction monitoring (MRM), results in an improvement in the sensitivity as well as the repeatability of the method, which has deficiencies especially in the analysis using HILIC. Overall, RP-LC–MS in MRM after derivatisation with 1-phenyl-3-methyl-5-pyrazolone (PMP) proved to be the most suitable method in terms of separation performance, sensitivity and repeatability for the analysis of monosaccharides. Detection limits in the nanomolar range were achieved, which corresponds to a mass concentration in the low µg/L range. The applicability of this method to different biological samples was investigated with various herbal liquors, pectins and a human glycoprotein. [ABSTRACT FROM AUTHOR]

Polyurethanes are widely used in daily life, from the textile industry to medical applications. In this study, a biocompatible and transparent coating from polyethylene glycol‐based polyurethanes including different type of saccharide (xylose as monosaccharide, sucrose as disaccharide, or starch as polysaccharide) is prepared. Prepared optically transparent polyurethanes are characterized with different instrumental analysis techniques and contact‐angle measurements. Thermogravimetric analysis data allow understanding that the synthesized saccharide based polyurethanes are resistant to high temperatures, which means that medical devices can be easily coated with one of the saccharide‐based polymers during the manufacturing process. The study results also show that synthesized polyurethane samples having a different kind of saccharides present high biocompatibility and transparency properties via In vitro cytotoxicity analysis and optic transparency tests. For xylose, sucrose, or starch containing polyurethanes, the tranmittance values are 97.72%, 85.20%, and 89.23%, respectively. In addition, scanning electron microscope images show that the samples also have smooth surfaces which can be used for proper coating of medical devices. Consequently, this manuscript addresses synthesis and characterization of the optically transparent polyurethanes based on specific saccharides for biocompatible and transparent surfaces especially in optic medical devices such as colonoscopy applications and laparoscopic detection probes. [ABSTRACT FROM AUTHOR]

The aim of this study was to evaluate the effect of five saccharides osmotic agents on the mass transfer kinetics during osmotic dehydration (OD) and freeze‐drying kinetics, as well as physical properties of freeze‐dried apple slices. The results demonstrated that the water loss (WL) and solid gain (SG) efficiency of the samples osmotic with monosaccharides were higher than that of the disaccharides and oligosaccharide based on k1 of Peleg model (fructose: k1 = 155.0, glucose: k1 = 139.0, sucrose: k1 = 199.0, maltose: k1 = 270.2, and isomaltooligosaccharides: k1 = 351.5). The drying rate of osmotic samples (0.372 g·g−1·h−1 to 0.557 g·g−1·h−1) was lower than untreated sample (0.654 g·g−1·h−1) at the primary drying stage. A significant positive correlation among WL, SG, and hardness (WL: R2 =.888 and SG: R2 =.857) was confirmed. These results suggest that the saccharides are vital determinants for the mass transfer and quality of apple slices, which is meaningful knowledge for developing freeze‐dried products with expected texture. Novelty impact statement: The osmotic rate and the final solid gain of monosaccharide were higher than disaccharides and oligosaccharides.The primary drying rate of the samples decreased after osmotic process.The water sorption capacity of the samples treated by different osmotic conditions. [ABSTRACT FROM AUTHOR]

Background Irritable bowel syndrome (IBS) has been associated with diets rich in fermentable oligo-, di-, monosaccharides, and polyols (FODMAPs), and gluten. Most previous studies have been single-blind and have focused on the elimination of FODMAPs or provocation with single FODMAPs. The effect of gluten is unclear, large trials isolating the effect of gluten from that of FODMAPs are needed. Objectives The aims of this study were to ensure high intakes of a wide range of FODMAPs, gluten, or placebo, and to evaluate the effects on IBS symptoms using the IBS-severity scoring system (IBS-SSS). Methods The study was carried out with a double-blind, placebo-controlled, randomized 3-way crossover design in a clinical facility in Uppsala from September 2018 to June 2019. In all, 110 participants fulfilling the IBS Rome IV criteria, with moderate to severe IBS, were randomly assigned; 103 (90 female, 13 male) completed the trial. Throughout, IBS participants maintained a diet with minimal FODMAP content and no gluten. Participants were block-randomly assigned to 1-wk interventions with FODMAPs (50 g/d), gluten (17.3 g/d), or placebo, separated by 1-wk washout. All participants who completed ≥1 intervention were included in the intention-to-treat analysis. Results In participants with IBS (n  = 103), FODMAPs caused higher IBS-SSS scores (mean 240 [95% CI: 222, 257]) than placebo (198 [180, 215]; P  = 0.00056) or gluten (208 [190, 226]; P  = 0.013); no differences were found between the placebo and gluten groups (P  = 1.0). There were large interindividual differences in IBS-SSS scores associated with treatment. No adverse events were reported. Conclusion In participants with IBS, FODMAPs had a modest effect on typical IBS symptoms, whereas gluten had no effect. The large interindividual differences in responses to the interventions warrant further detailed studies to identify possible underlying causes and enable individual prediction of responses. This trial was registered at www.clinicaltrials.gov as NCT03653689. [ABSTRACT FROM AUTHOR]

Dual detection systems are of interest for rapid, accurate data collection in sensing systems and in vitro testing. We introduce an IrIII complex with a boronic acid receptor site attached to the 2‐phenylpyridine ligand as an ideal probe with photo‐ and electrochemical signals that is sensitive to monosaccharide binding in aqueous solution. The complex displays orange luminescence at 618 nm, which is reduced by 70 and 40 % upon binding of fructose and glucose, respectively. The electro‐chemiluminescent signal of the complex also shows a direct response to monosaccharide binding. The IrIII complex shows the same response upon incorporation into hydrogel matrices as in solution, thus demonstrating the potential of its integration into a device, as a nontoxic, simple‐to‐use tool to observe sugar binding over physiologically relevant pH ranges and saccharide concentrations. Moreover, the complex's luminescence is responsive to monosaccharide presence in cancer cells. [ABSTRACT FROM AUTHOR]

The physicochemical properties and biological activities of polysaccharides depend on their structures. Monosaccharide composition analysis is indispensable for the structural characterization of polysaccharides and is helpful in the quality control of polysaccharide preparation. Here, using a model mixture and tamarind seed polysaccharide as examples, we demonstrated that a quantitative 2D NMR method, gsHSQC i (three gradient-selective Heteronuclear Single Quantum Coherence spectra acquired with incremented repetition times, i = 1, 2, 3) can directly quantify a variety of monosaccharides in solution with adequate precision and accuracy, requiring no derivatization, postprocessing steps and column separation. Both anomeric and non-anomeric signals of monosaccharides can be utilized for content determination. More accurate quantification of fructose in a mixture containing nine monosaccharides is obtained, which is difficult to achieve by quantitative 1D 1HNMR and the common PMP-HPLC method (high-performance liquid chromatography through pre-column derivatization with 1-phenyl-3-methyl-5-pyrazolone) due to the peak overlapping and the poor derivatization efficiency, respectively. The results also revealed that Na[Fe(EDTA)] can serve as a proper relaxation-enhancing agent for saccharide samples to save experimental time. We expect that this approach can be applied as an alternative to analyzing the monosaccharide composition and be helpful in interpreting the structure of polysaccharides. [Display omitted] • Direct quantification of a variety of monosaccharides in the mixture without derivatization and column separation • Measure the monosaccharide mixture directly without a pre-established standard curve for each monosaccharide • More non-anomeric signals can be utilized for quantification in gsHSQC i compared with qHNMR • Na[Fe(EDTA)] is used as a proper relaxation-enhancing agent to save experimental time • DMSO 2 is used as an internal reference for quantitation. [ABSTRACT FROM AUTHOR]

A self-healing smart PhC hydrogel sensor that combines the optical property of photonic crystal and the dynamic regeneration property of boronate ester bond has been prepared for determination of glucose and related saccharides using Debye diffraction ring detection. The boronate ester bond formed through phenylboronic acid and dopamine endows the hydrogel network self-healing ability, and the tensile stress of the healing hydrogel can recover to 94.4%; this excellent self-healing property can effectively improve the reliability and lifetime of the hydrogel. Due to the high bonding capacity between 1,2- and 1,3-diol and phenylboronic acid, the hydrogel sensor has a good recognition ability for glucose and related saccharides. The reaction between the monosaccharides and the phenylboronic acid group makes the sensor swell and the diameter of the Debye diffraction ring decrease. The sensor shows good reuse and responsive ability for saccharides; the RSD of the recoverability assays is 4.3%. The determination range of the sensor to glucose is 0.5 to 12 mM. The sensor also has good response to glucose in urine, exhibiting potential application value in the preliminary screening of diabetes. Although the sensor has poor selectivity for specific monosaccharides, the process of measuring the Debye ring makes the determination no longer rely on expensive and complicated equipment and greatly simplifies the determining process and reduces the cost of determination, which shows a broad application prospect. [ABSTRACT FROM AUTHOR]