Monosaccharide Analysis After One-Pot Derivatization Followed by Reverse-Phase Liquid Chromatography Separation and UV/Vis Detection.

Derivatization of monosaccharides with 1-phenyl-3-methyl-5-pyrazolone (PMP) introduces two chromophores per sugar molecule. Their separation on a superficially porous C18 reverse-phase column, using common liquid chromatography equipment, results in short analysis times (under 20 min) and high sensitivity (limit of quantitation 1 nmol). This method allows for complex monosaccharide mixtures to be separated and quantified using a reasonably simple and safe derivatization procedure.

[Analysis and prospect of correlation between relative molecular weight and efficacy of polysaccharides from medicinal plant resources].

Polysaccharides from medicinal plant resources are a kind of polymers extracted from medicinal plants. They are complex long chains formed by different monosaccharides connected via glucosidic bonds. These polysaccharides usually have straight chain and branched chain structures, and their relative molecular weight changes greatly. Modern studies have shown that the biological activi-ty of polysaccharides from medicinal plant resources is closely related to their relative molecular weight. This paper first reviewed the preparation and detection methods of polysaccharides from medicinal plant resources with different relative molecular weights. Then, the paper summarized and analyzed the general experience of the correlation between efficacy and relative molecular weight of polysaccharides from medicinal plant resources with different molecular weights. It was considered that polysaccharides with large relative molecular weights(>100 kDa) play a leading role in immune regulation. Polysaccharides with medium relative molecular weights(10-100 kDa) play a leading role in immune regulation and the protection of the liver. Polysaccharides with small relative molecular weights(<10 kDa) play a leading role in anti-oxidation, regulation of intestinal flora, regulation of blood glucose and lipids, anti-fatigue, and the protection of nerves. Therefore, precise development of polysaccharides from medicinal plant resources based on relative molecular weight is expected to improve their biological activity and application value.

Physicochemical Characterization, Antioxidant and Anticancer Activity Evaluation of an Acidic Polysaccharide from Alpinia officinarum Hance.

AHP-3a, a triple-helix acidic polysaccharide isolated from Alpinia officinarum Hance, was evaluated for its anticancer and antioxidant activities. The physicochemical properties and structure of AHP-3a were investigated through gel permeation chromatography, scanning electron microscopy (SEM), Fourier transform infrared spectroscopy, and nuclear magnetic resonance (NMR) spectroscopy. The weight-average molecular weight of AHP-3a was 484 kDa, with the molar percentages of GalA, Gal, Ara, Xyl, Rha, Glc, GlcA, and Fuc being 35.4%, 21.4%, 16.9%, 11.8%, 8.9%, 3.1%, 2.0%, and 0.5%, respectively. Based on the results of the monosaccharide composition analysis, methylation analysis, and NMR spectroscopy, the main chain of AHP-3a was presumed to consist of (1→4)-α-D-GalpA and (1→2)-α-L-Rhap residues, which is a pectic polysaccharide with homogalacturonan (HG) and rhamnogalacturonan-I (RG-I) structural domains containing side chains. In addition, the results of the antioxidant activity assay revealed that the ability of AHP-3a to scavenge DPPH, ABTS, and OH free radicals increased with an increase in its concentration. Moreover, according to the results from the EdU, wound healing, and Transwell assays, AHP-3a can control the proliferation, migration, and invasion of HepG2 and Huh7 hepatocellular carcinoma cells without causing any damage to healthy cells. Thus, AHP-3a may be a natural antioxidant and anticancer component.

Two novel polysaccharides from Huangshui: Purification, structure, and bioactivities.

In this study, the novel polysaccharides named HSP-0 M and HSP-0.1 M were successfully purified from Huangshui (HS), and their structural properties and bioactivities were investigated. Structural analysis revealed that HSP-0 M had a molecular weight of 493.87 kDa and was composed of arabinose, galactose, glucose, xylose, and mannose in a molar ratio of 1.48:1.09:26.52:1.33:1.00. On the other hand, HSP-0.1 M was made up of fructose, arabinose, galactose, glucose, xylose, mannose, ribose, galacturonic acid and glucuronic acid in a ratio of 2.67:26.00:29.10:36.83:16.22:30.53:1.00:1.43:3.64 with a molecular weight of 157.6 kDa. Methylated and 2D NMR analyses indicated that T-Glcp-(1 â†’ 4)-Glcp-(1 â†’ 2)-Glcp-(1 â†’ 3)-Glcp was the primary chain of HSP-0 M, and the backbone of HSP-0.1 M was made up of →3)-Galp-(1 â†’ 6)-Manp-(1 â†’ 3)-Glcp-(1 â†’ 6)-Glcp-(1 â†’ 2)-Manp-(1 â†’ 6)-Glcp-(1 â†’ 3)-Galp. Morphological research showed that both polysaccharides were homogeneous as well as exhibit a web-like structure and an irregular lamellar structure. Furthermore, HSP-0 M demonstrated the capacity to safeguard Lactococcus lactis from damage caused by low temperatures and freeze-drying, while HSP-0.1 M exhibited noteworthy antioxidant activity. These results established a theoretical foundation for the applications of HSPs in food products, cosmetics, and medicines.

Structural Characterization of Disaccharides Using Cyclic Ion Mobility Spectrometry and Monosaccharide Standards.

To understand the mode of action of bioactive oligosaccharides, such as prebiotics, in-depth knowledge about all structural features, including monosaccharide composition, linkage type, and anomeric configuration, is necessary. Current analytical techniques provide limited information about structural features within complex mixtures unless preceded by extensive purification. In this study, we propose an approach employing cyclic ion mobility spectrometry (cIMS) for the in-depth characterization of oligosaccharides, here demonstrated for disaccharides. We were able to separate galactose and glucose anomers by exploiting the high ion mobility resolution of cIMS. Using the obtained monosaccharide mobilograms as references, we determined the composition and anomeric configuration of 4ß-galactobiose by studying the monosaccharide fragments generated by collision-induced dissociation (CID) before the ion mobility separation. Drift times and individual MS2 spectra of partially resolved reducing-end anomers of 4ß-galactobiose, 4ß-galactosylglucose (lactose), and 4ß-glucosylglucose (cellobiose) were obtained by deconvolution using CID fragmentation induced in the transfer region between the cIMS cell and TOF analyzer. The composition and anomeric configuration of the reducing end anomers of these disaccharides were identified using cIMS2 approaches, where first each anomer was isolated using cIMS and individually fragmented, and the monosaccharide fragments were again separated by cIMS for comparison with monosaccharide standards. With these results we demonstrate the promising application of cIMS for the structural characterization of isomeric oligosaccharides.

Extraction, purification, structural characteristics, bioactivity and potential applications of polysaccharides from Avena sativa L.: A review.

Avena sativa L. (A. sativa L.), commonly known as oat, is a significant cereal grain crop with excellent edible and medicinal value. Oat polysaccharides (OPs), the major bioactive components of A. sativa L., have received considerable attention due to their beneficial bioactivities. However, the isolation and purification methods of OPs lack innovation, and the structure-activity relationship remains unexplored. This review emphatically summarized recent progress in the extraction and purification methods, structural characteristics, biological activities, structure-to-function associations and the potential application status of OPs. Different materials and isolation methods can result in the differences in the structure and bioactivity of OPs. OPs are mainly composed of various monosaccharide constituents, including glucose, arabinose and mannose, along with galactose, xylose and rhamnose in different molar ratios and types of glycosidic bonds. OPs exhibited a broad molecular weight distribution, ranging from 1.34 × 105 Da to 4.1 × 106 Da. Moreover, structure-activity relationships demonstrated that the monosaccharide composition, molecular weight, linkage types, and chemical modifications are closely related to their multiple bioactivities, including immunomodulatory activity, antioxidant effect, anti-inflammatory activity, antitumor effects etc. This work can provide comprehensive knowledge, update information and promising directions for future exploitation and application of OPs as therapeutic agents and multifunctional food additives.

Synthesis and ab initio conformational investigation of a series of model sulfated α-L-iduronopyranosides.

Due to the all-axial orientation of the OH-groups in the 1C4 chair conformation considered standard for L-hexapyranosides, including l-iduronopyranoside - a component of many biologically and medically significant sulfated glycans, these monosaccharides can be anticipated to display unusual conformations upon the introduction of bulky and charged substituents. Herein we describe the synthesis of a series of iduronopyranoside derivatives with varying sulfation patterns, which were studied computationally using the DLPNO-MP2 approach and by means of analyzing their chemical shifts to ascertain the effects sulfation has on the conformation of the iduronopyranoside ring.

Efficient degradation and enhanced α-glucosidase inhibitory activity of apricot polysaccharides through non-thermal plasma assisted non-metallic Fenton reaction.

Dielectric barrier discharge (DBD) was a commonly used non-thermal plasma (CP) technology. This paper aimed to enhance the biological activity of apricot polysaccharides (AP) by using dielectric barrier discharge (DBD-CP) assisted H2O2-VC Fenton reaction for degradation. The degradation conditions were optimized through response surface methodology. The molecular weight (Mw) of degraded apricot polysaccharides (DAP) was 19.71 kDa, which was 7.25 % of AP. The inhibition rate of DAP (2 mg/mL) was 82.8 ± 3.27 %, which was 106.87 % higher than that of AP. DBD-CP/H2O2-VC degradation changed the monosaccharide composition of AP and improved the linearity of polysaccharide chains. In addition, a novel apricot polysaccharide DAP-2 with a Mw of only 6.60 kDa was isolated from DAP. The repeating units of the main chain of DAP-2 were →4)-α-D-GalpA-(1 →, the branch chain was mainly composed of α-D-GalpA-(1 â†’ 2)-α-L-Rhap-(1→ connected to O-3 position →3,4)-α-D-GalpA-(1→. The complex structure formed by the combination of DAP-2 and α-glucosidase was stable. DAP-2 had a higher α-glucosidase binding ability than the acarbose. These results suggested that DAP-2 had the potential to be developed as a potential hypoglycemic functional food and drug.

Chemical characterization of polysaccharides from Gracilaria gracilis from Bizerte (Tunisia).

Polysaccharides were extracted from Gracilaria gracilis collected from Manzel Jemil Lake in Bizerte Tunisia, with two different solvents (water and NaOH 0.3 M). Different assays were performed on samples (total sugars, neutral sugars, uronic acids, anhydrogalactose, proteins, sulphates, pyruvates), followed by high performance anion-exchange chromatography (HPAEC) to observe the monosaccharide composition, high pressure size exclusion chromatography with multi-angle laser light scattering (HPSEC-MALS) to obtain the molecular mass, Fourier transform infrared spectroscopy (FTIR), and 1D and 2D nuclear magnetic resonance (NMR) to access to structural data. Results have shown that the polysaccharide extracted from Gracilaria gracilis collected from Manzel Jemil Lake in Bizerte Tunisia, is of agar type but with high molecular mass and some original structural features. Hence, the sample was found to contain 9 % of pyruvate groups and is partly sulphated at the C4 of ß-d-galactose and methylated on C2 of anhydro-α-l-galactose. The polymer from G. gracilis from Bizerte thus presents a never described structure that could be interesting for further rheological or biological activities applications.

Effect of extraction method on the structure and bioactivity of polysaccharides from activated sludge.

Resource recovery is a pivotal facet of waste activated sludge treatment, particularly within the framework of carbon neutrality and the circular economy. Polysaccharides are emerging as a valuable resource from waste activated sludge, and the choice of extraction method affects the properties of the polysaccharides, which is of utmost importance for subsequent application. This investigation examined the effects of six extraction methods (i.e., acidic, alkaline, ultrasonication, hot-water, microwave, and electric treatments) on the yield, chemical composition, structural characteristics, and bioactivities of polysaccharides extracted from sludge. For each extraction method, two operational parameters, namely the treatment time and strength (e.g., the acid and alkali concentration), were initially optimized in terms of the polysaccharide yield. The polysaccharide yield varied from 1.03 ± 0.12 % to 5.34 ± 0.10 % adopting the extraction methods under optimized conditions, and the alkaline extraction method had the highest yield of polysaccharides with a treatment time of 120 min and NaOH concentration of 1 %. At least one polysaccharide fraction was successfully purified from the crude polysaccharide of each extraction method. The compositions and structures of these fractions, including carbohydrate, protein, sulfate, uronic acid contents, and monosaccharide compositions, were determined. Carbohydrate was the dominant component, with the hot-water-2 fraction having the highest carbohydrate content (77.90 % ± 2.02 %). Monosaccharides in the polysaccharides were measured, with mannose, rhamnose, glucose, and xylose being found in all fractions, whereas ribose was exclusively found in the acid-1 fraction. The molecular weights of these fractions ranged between 1.60 × 104 Da and 7.11 × 106 Da. Furthermore, the bioactivities of the polysaccharides, encompassing five anti-oxidant and three anti-coagulant properties, were assessed, with the ultrasonication-1 fraction having superior performance in seven of the assays. Finally, the association among the fractions in terms of composition and bioactivity was assessed adopting cluster analysis and regression methods. The findings underscore the effect of the extraction method on the properties of polysaccharides extracted from sludge, thereby providing valuable insights for the prospective applications of polysaccharides.

Identification of benzothiazole derived monosaccharides as potent, selective, and orally bioavailable inhibitors of human and mouse galectin-3; a rare example of using a S···O binding interaction for drug design.

As a result of our continued efforts to pursue Gal-3 inhibitors that could be used to fully evaluate the potential of Gal-3 as a therapeutic target, two novel series of benzothiazole derived monosaccharides as potent (against both human and mouse Gal-3) and orally bioavailable Gal-3 inhibitors, represented by 4 and 5, respectively, were identified. These discoveries were made based on proposals that the benzothiazole sulfur atom could interact with the carbonyl oxygen of G182/G196 in h/mGal-3, and that the anomeric triazole moiety could be modified into an N-methyl carboxamide functionality. The interaction between the benzothiazole sulfur and the carbonyl oxygen of G196 in mGal-3 was confirmed by an X-ray co-crystal structure of early lead 9, providing a rare example of using a S···O binding interaction for drug design. It was found that for both the series, methylation of 3-OH in the monosaccharides caused no loss in h & mGal-3 potencies but significantly improved permeability of the molecules.

Modified acid polysaccharide derived from Salvia przewalskii with excellent wound healing and enhanced bioactivity.

Acid polysaccharide was extracted from Salvia przewalskii root powders (PSP), purified by diethylaminoethyl cellulose column (DEAE-52) and molecular sieve (PSP2). PSPm1 was obtained by modifying PSP2 with nitrite and phosphoric acid. The chemical structure of PSP2 and PSPm1 exhibited notable distinctions, primarily due to the absence of arabinose and promotion of glucuronic acid (GlcA). The structure of PSPm1 was deduced through the utilization of 1H, 13C, and 2-D NMR. The main chain was linked by α-D-Galp(1 â†’ 3)-α-Glcp-(1 â†’ fragments and →6)-ß-D-Galp fragments, with the presence of →4)-α-D-GlcpA-(1 â†’ 6)-ß-D-Galp-(1 â†’ ï¼Œ â†’ 4)-α-D-GalAp-(1 â†’ 2,4)-α-D-Rhap-(1 â†’ fragments and →6)-α-Glcp-(1 â†’ 2,4)-ß-D-Manp-(1 â†’ fragments. PSPm1 exhibited different immunoregulatory bioactivity in vitro, including haemostatic effects indicated by activated clotting time of 55.5 % reduction by the activated clotting time (ACT) test and wound healing function in vivo. PSPm1 also displayed better anti-tumor biological effects than unmodified. The structure-activity dissimilarity between PSP2 and PSPm1 primarily stems from variations in molecular weight (Mw), monosaccharide composition, and branching patterns. The modification of polysaccharides from the extract residues of Chinese medicinal materials may be a new form of drug supplements.

Reagent-controlled chemo/stereoselective glycosylation of ʟ-fucal to access rare deoxysugars.

2,6-Dideoxy sugars constitute an important class of anticancer antibiotics natural products and serve as essential medicinal tools for carbohydrate-based drug discovery and vaccine development. In particular, 2-deoxy ʟ-fucose or ʟ-oliose is a rare sugar and vital structural motif of several potent antifungal and immunosuppressive bioactive molecules. Herein, we devised a reagent-controlled stereo and chemoselective activation of ʟ-fucal, enabling the distinctive glycosylation pathways to access the rare ʟ-oliose and 2,3-unsaturated ʟ-fucoside. The milder oxo-philic Bi(OTf)3 catalyst induced the direct 1,2-addition predominantly, whereas B(C6F5)3 promoted the allylic Ferrier-rearrangement of the enol-ether moiety in ʟ-fucal glycal donor, distinguishing the competitive mechanisms. The reagent-tunable modular approach is highly advantageous, employing greener catalysts and atom-economical transformations, expensive ligand/additive-free, and probed for a diverse range of substrates comprising monosaccharides, amino-acids, bioactive natural products, and drug scaffolds embedded with susceptible or labile functionalities.

Effect of monosaccharide composition and proportion on the bioactivity of polysaccharides: A review.

Polysaccharides have been widely used in pharmaceutical and food industries due to their diverse bioactivity, high safety, and few or no side effects. However, inability to quickly produce, screen, and synthesize bioactive polysaccharides is the limiting factor for their development and application. Structural features determine and influence the bioactivity of polysaccharides. Among them, monosaccharide is the basic unit of polysaccharide, which not only affects electrification, functional group, and bioactivity of polysaccharide but also is one of the simplest polysaccharide indexes to be detected. At present, effects of monosaccharide composition and proportion on anti-inflammatory, antioxidant, antitumor, immunomodulatory, antibacterial, and prebiotic activities of polysaccharides are reviewed. Further problems need to be considered during regulation and analysis of monosaccharide composition and proportion of polysaccharides. Overall, present work will provide help and reference for production, development, and structure-function investigation of polysaccharides based on their monosaccharide.

Complete composition analysis of polysaccharides based on HPAEC-PAD coupled with quantitative analysis of multi-components by single marker.

INTRODUCTION: Monosaccharide compositions analysis (MCA) is indispensable for structural characterisations and structure-activity relationships of plant polysaccharides. OBJECTIVES: To develop a concise and direct MCA method, we established a quantitative analysis of the multi-monosaccharaides by single marker (QAMS) by high-performance anion-exchange chromatography with pulsed-amperometric detection (HPAEC-PAD) method. METHODOLOGY: A stable and reproducible HPAEC-PAD method for simultaneous determination of aldoses, ketoses and uronic acids (i.e., l-arabinose, d-xylose, d-ribose, l-rhamnose, d-fucose, d-mannose, d-glucose, d-galactose, d-fructose, d-glucuronic acid and d-galacturonic acid) was established by systematic optimisation of stationary phases, column temperatures and elution programmes. On this basis, the QAMS method was proposed through comprehensive investigations of relative correction factor (RCF) variations under different influencing factors, for example, sample concentrations, flow rates, and column temperatures. RESULTS: Using rhamnose as an internal reference standard, the contents of the other monosaccharide components in polysaccharides from Panax quinquefolium L. and Achyranthes bidentata Bl. samples were simultaneously determined by QAMS, and there was no significant difference between the results from the QAMS and external standard method (t test, P > 0.520). In addition, a MCA fingerprinting of 30 batches of P. quinquefolium polysaccharide was established by HPAEC-PAD, and six common peaks were assigned and determined. CONCLUSIONS: The established HPAEC-PAD-QAMS method was successfully applied to the MCA of polysaccharides from P. quinquefolium and A. bidentata after optimisation of hydrolysis conditions. HPAEC-PAD-QAMS was proposed and established for MCA of plant polysaccharides for the first time.

Extraction, structure, pharmacological activity, and structural modification of Lilium polysaccharides.

Polysaccharides primarily composed of glucose, arabinose, rhamnose, xylose, and galactose are pharmacologically active ingredients in Lilium. The pharmacological activities shown by polysaccharides from Lilium include antioxidant, anti-tumor, immunomodulatory, hypoglycemic, bacteriostatic, and radiation protection effects. This review provides a comprehensive summary of the distribution of Lilium medicinal resources in China, current extraction and purification methods of Lilium polysaccharide (LP), the strategies used for analyzing the polysaccharide structure and monosaccharide composition in LP, and the pharmacological activities and structural modification of LP. This review provides a basis for the development and clinical application of LP along with the conservation and utilization of Lilium resources.

Development of a joint derivatization protocol for the unequivocal identification of the monosaccharide composition in four dendrobium polysaccharides and free monosaccharide by GC-MS.

The determination of monosaccharides is crucial for studying the structure of polysaccharides and the composition of free monosaccharides in living organisms. Based on previous derivatization gas chromatography-mass spectrometry (GC-MS) methods, we aimed to develop a novel analytical protocol for better quantifying monosaccharides. In this study, sugar alcohol acetylation, saccharonitrile acetylation, silylation and a combination of sugar alcohols acetylation and saccharonitrile acetylation were compared. The optimal method was verified with the monosaccharide determination of four polysaccharides and four free monosaccharides from Dendrobium. The results showed that the novel combined derivatization method was superior to the other three methods in terms of content analysis of monosaccharides. Furthermore, it possessed good linearity (all calibration curves showed relative coefficients ≥ 0.999), sensitivity, precision (relative standard deviation < 2%), and accuracy (recovery, 95.7-105%). Finally, the novel method established in this study was successfully employed in determining the monosaccharide composition of four polysaccharides and four free monosaccharide samples from Dendrobium.

Identification and Quantification of Monosaccharides from Fungal Cell Walls and Exopolysaccharides by Gas Chromatography Coupled to Mass Spectrometry.

The fungal cell wall and secreted exopolysaccharides play an important role in the interactions between fungi and their environment. Despite their central role in fungal biology, ecology, and host-pathogen interactions, the composition of these polymers and their synthetic pathways are not well understood. The protocols presented in this article describe an approach to isolate fungal cell wall polysaccharides and to identify and quantify the monosaccharide composition of these polymers by gas chromatography-mass spectrometry (GC-MS). © 2023 The Authors. Current Protocols published by Wiley Periodicals LLC. Basic Protocol: O-methyl trimethylsilyl monosaccharide derivatives composition analysis by GC-MS Support Protocol: Fungal cell wall extraction.

[Relationship between immune regulation and structure of polysaccharides].

Polysaccharides have significant immunomodulatory activity and have good development value in food and medicine fields. At present, there are many studies on the chemical structure and immune activity of polysaccharides, but the relationship between them of polysaccharides has not been fully explained, which limits the further development and utilization of polysaccharide resources. The immune activity of polysaccharides is closely related to their own structure. This paper systematically summarized the relationship between the relative molecular weight, monosaccharide composition, glycosidic bond types, chemical modification, and advanced conformation of polysaccharides and the immune regulation, aiming to provide references for the profound study of polysaccharide structure-activity relationship and utilization of polysaccharides.

Structural Characterization, Simulated Digestion and Anti-Aging Activities of an Acidic Polysaccharide from Salvia Miltiorrhiza.

An acidic polysaccharide (SMP) with a molecular weight (Mw) of 1.28 × 106 Da was isolated from Salvia miltiorrhiza. The monosaccharide composition in molar percentages was rhamnose (Rha): galacturonic acid (GalA): galactose (Gal): arabinose (Ara) = 6.15: 55.98: 21.27: 16.69. The results of simulated digestion in vitro showed that SMP was not degraded in saliva, gastric juice or intestinal juice. The Y maze test and new object recognition test showed that SMP could improve the working memory impairment of aging mice. SMP could also increase the activity of superoxide dismutase (SOD) and catalase (CAT) in serum and brain tissue, decrease the content of malondialdehyde (MDA), decrease the levels of interleukin-6 (IL-6) and tumor necrosis factor-α (TNF-α) in brain tissue, and increase the content of short-chain fatty acids (SCFA) in the intestine. In addition, SMP could also regulate the intestinal flora structure, including increasing the relative abundance of Firmicutes and Bacteroidetes and decreasing the relative abundance of Proteobacteria. This work lays a foundation for the development of functional foods related to Salvia miltiorrhiza.