Activity Of Oligosaccharides Research Articles

Purification, Source Exploration, and Bioactivity Evaluation of Oligosaccharides in Sijunzi Decoction.

Sijunzi decoction (SJZD) has been widely used to treat splenic deficiency syndrome. Previous studies confirmed that polysaccharides and non-polysaccharides (NPS) are the main active components of SJZD. This study aimed to investigate the composition and activity of oligosaccharides in NPS. In this study, the oligosaccharide component (named SJZD-OGS), consisting of several different oligosaccharides, was separated and purified from non-polysaccharides of SJZD (SJZD_NPS). Ultra-high-performance liquid chromatography-ion mobility spectrometry-quadrupole time-of-flight mass spectrometry (UHPLC-IMS-QTOF/MS), matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF-MS), and high-performance anion-exchange chromatography with pulsed amperometric detection (HPAEC-PAD) were used to analyze SJZD-OGS. SJZD-OGS, with a molecular weight of 2178Da, was composed of glucose and fructose, and its chemical composition mainly included fructo-oligosaccharides (FOS) with a degree of polymerization of 3-14 (DP 3-14). The results of oligosaccharide source exploration demonstrated that the chemical composition of SJZD-OGS was different from that of the oligosaccharides of each herb in SJZD. In addition, SJZD-OGS showed good anti-inflammatory activity on macrophage cells and intestinal epithelial cell protective activity. The present work provides experimental evidence for elucidating the pharmaceutical components of SJZD and presents an effective strategy for the research of oligosaccharides in traditional Chinese medicine (TCM).

Peroxidative depolymerization of fucosylated glycosaminoglycan: Bond-cleavage pattern and activities of oligosaccharides

Peroxidative depolymerization is often used to elucidate the structure and structure-activity relationship of fucosylated glycosaminoglycan (FG), while the selectivity of bond cleavage and structural characteristics of the resulting fragments remain to be confirmed. Here, the FG from Stichopus variegatus (SvFG) was depolymerized by H2O2, and a series of yielded mono- and oligo-saccharides were purified. Almost all the non-reducing ends of oligosaccharides were d-GalNAc4S6S, suggesting that GlcA-β1,3-GalNAc4S6S linkage was preferentially cleaved. The model reactions showed the glycosidic bond of uronate was more susceptible than those of N-acetyl hexosamine and fucose, which should be due to bond energy of the anomeric CH. The reducing ends of oligosaccharides include C4–C6 saccharic acid and GalNAc or GalNAcA, which should be derived from the oxidation of the reducing end. A hexasaccharide with tartaric acid exhibited increased anti-iXase activity, suggesting the oxidation of reducing end did not impair the anti-iXase activity of FG-derived oligosaccharides.

Acid hydrolysis of spent coffee grounds: effects on possible prebiotic activity of oligosaccharides

BackgroundSpent coffee grounds (SCG) are a promising source of natural by-products which can be used for different purposes. In this work, a possible use of oligosaccharides isolated from SCG as functional ingredients was investigated. SCGs were treated with an acid hydrolysis at high temperature (200 °C) in a closed reactor setting reaction time of 30, 60 and 90 s depending on the sample (original or defatted). A comprehensive study of the resulted water-soluble hydrolysate using a high-resolution mass spectrometry analysis was performed. Additionally, the growth of four Lactobacillus strains was tested to assess the prebiotic potential of the hydrolysate.ResultsOligosaccharide chains formed by hexoses with a degree of polymerization ranging from 3 to 6 were identified and characterized. Regardless of the composition and the reaction time of hydrolysis, the bacterial activity of SCG extracts exhibited significantly higher values than the well-known versatile carbohydrate used by food industry, i.e., inulin.ConclusionsThe results pave the way toward the use of hydrolysate SCG as an innovative ingredient intended to fortify food formulations. The diversity in coffee oligosaccharides composition suggests their selective prebiotic activity for specific bacterial strains.Graphical

Effects of Oligoarabinoxylans From Aristida pungens Leaves on Germination and Growth of Barley

The objective of this study was to investigate a possible biological activities of oligosaccharides resulting from the hydrolysis of parietal hemicelluloses of the foliar tissue of Aristida pungens. Known for its developed, fiber rich foliar tissue, this perennial grasses is widely distributed on the arid and sub-desertic regions of Algeria. In order to identify added value application for the cell wall hemicellulose of Aristida pungens (Poaceae), the polymers were hydrolyzed enzymatically and after size exclusion chromatography, oligosaccharide fragments were tested for their abilities to modify the germination and growth of barley seeds (Hordeum vulgare). Five fractions were separated with different compositions and molecular weights. The low molecular weight fractions were mostly composed of oligoxylans, while the high molecular weight fractions consisted of oligo-glucuronoarabinoxylans. Biological tests suggested that the oligosaccharide fractions and particularly the low molecular weight fraction could promote germination and increase root bio-mass at low concentrations or reduce it at higher concentrations, suggesting a possible bio-stimulating application.

An Overview of Structural Aspects and Health Beneficial Effects of Antioxidant Oligosaccharides.

Non-digestible oligosaccharides are versatile sources of chemical diversity, well known for their prebiotic actions, found naturally in plants or produced by chemical or enzymatic synthesis or by hydrolysis of polysaccharides. Compared to polyphenols or even polysaccharides, the antioxidant potential of oligosaccharides is still unexplored. The aim of the present work was to provide an up-to-date, broad and critical contribution on the topic of antioxidant oligosaccharides. The search was performed by crossing the words oligosaccharides and antioxidant. Whenever possible, attempts at establishing correlations between chemical structure and antioxidant activity were undertaken. The most representative in vitro and in vivo studies were compiled in two tables. Chitooligosaccharides and xylooligosaccharides and their derivatives were the most studied up to now. The antioxidant activities of oligosaccharides depend on the degree of polymerization and the method used for depolymerization. Other factors influencing the antioxidant strength are solubility, monosaccharide composition, the type of glycosidic linkages of the side chains, molecular weight, reducing sugar content, the presence of phenolic groups such as ferulic acid, and the presence of uronic acid, among others. Modification of the antioxidant capacity of oligosaccharides has been achieved by adding diverse organic groups to their structures, thus increasing also the spectrum of potentially useful molecules. A great amount of high-quality evidence has been accumulating during the last decade in support of a meaningful antioxidant activity of oligosaccharides and derivatives. Ingestion of antioxidant oligosaccharides can be visualized as beneficial to human and animal health.

Preparation, characterization, and cytokine-stimulating activity of oligosaccharides from Tremella fuciformis Berk.

The Tremella fuciformis Berk polysaccharides (TP) have significant cytokine-stimulating activity and low oral bioavailability owing to their large molecular volume. Identifying and studying the smallest active structure of TP can potentially be beneficial for further utilization and research, therefore, TP was hydrolyzed and fractionated to obtain its (1→3)-mannan backbone fragments. The fragments were further isolated by ion-exchange resin, ultrafiltration, gel, and HPLC chromatography, and three oligosaccharide fractions, named TL4-1, TL4-2, TL4-3, were obtained. According to the determination of their physicochemical properties, they were composed of Man, and after methylation analysis they were mainly characterized as (1→3)-mannan oligosaccharides with a straight chain. TL4-1 contained di-, trisaccharides, TL4-2 included tetra-, penta-saccharides, and TL4-3 was made up of hex-, hepta-, octa-saccharides, according to LC-ESI/MS analysis. Cytokine stimulation experiments showed that the degree of polymerization (DP) should be more than six to maintain the activity of mannosan. Therefore, the smallest active unit of oligo-mannose was determined. PRACTICAL APPLICATIONS: This paper reports the physical and chemical parameters, structure and biological potential of oligosaccharides from T. fuciformis Berk, a common edible fungus. Tremella has been used as an improving immunity drug in China with good effect. Oligosaccharides are more easily digested and utilized by human body, and maintain good activity. These results can increase people's interest in the product, and thus have a positive impact on the oligosaccharides of Tremella as health food.

Abstract 1374: Synthetic heparan sulfate oligosaccharides inhibit endothelial cell functions essential for angiogenesis

Abstract Heparan sulfate (HS), a linear glycosaminoglycan, is an essential structural component required for the activity of numerous angiogenic cytokine-receptor signalling complexes. To exploit the potential of inhibiting HS-dependent signalling complexes we synthesized a series of heparan sulfate oligosaccharides containing up to 12 saccharide residues with variable but defined sulfation patterns. The ability of oligosaccharides to compete with HS in FGF2, VEGF and IL-8 binding significantly increased with the length of oligosaccharides and especially with additional sulfate groups incorporated at specific positions in the hexuronic acid and glucosamine. In this competition assay, oligosaccharides exhibited higher levels of inhibition of FGF2 binding to HS than of VEGF and IL-8 binding to HS. Correspondingly, the inhibitory potential of oligosaccharides against FGF2-, VEGF- and IL-8-mediated endothelial cell responses was greater in longer species of oligosaccharides that bore more sulfate residues. Oligosaccharides inhibited cytokine-induced endothelial cell migration to the same extent as kinase inhibitors targeting FGF receptors or VEGF receptor 2 (VEGFR2). In contrast, FGF2-induced endothelial cell proliferation was only inhibited when cells were treated with an oligosaccharide composed of 12 saccharide residues at a concentration that significantly exceeded that of the FGFR inhibitor suggesting that oligosaccharides mainly interfere with the migration, but not proliferation of endothelial cells. The ability of oligosaccharides to target endothelial cell migration correlated with their ability to ablate FGF2- or VEGF-induced accumulation of activated peripheral FAK-pY397 and actin polymerization at the cell periphery. More importantly, there was a strong correlation between oligosaccharide structure and the level of inhibition of endothelial tube formation. Correlating with the biological activity of oligosaccharides, FGF2- and VEGF-induced downstream signalling events were sensitive to the treatment with biologically active oligosaccharides that specifically reduced FRS2, VEGFR2, ERK1/2 and AKT phosphorylation. In conclusion, we have determined the critical number of HS saccharide residues and sulfation pattern required to inhibit endothelial cell responses to key angiogenic cytokines. Note: This abstract was not presented at the AACR 101st Annual Meeting 2010 because the presenter was unable to attend. Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 101st Annual Meeting of the American Association for Cancer Research; 2010 Apr 17-21; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2010;70(8 Suppl):Abstract nr 1374.

New approaches for mapping the recognition sites in protein–GAG interactions: a study of GAG binding by hepatocyte growth factor/scatter factor

Introduction The minimal size and structure of GAG that binds to a protein, as well as the site of GAG interaction on the protein surface, are crucial recognition features for understanding, and potentially modulating, protein–GAG interactions. Methods that are easily and generally applicable for investigating such interactions, irrespective of the GAG species involved, are very limited. We have been developing such methodologies using the example of hepatocyte growth factor/scatter factor (HGF/SF). We have previously shown HGF/SF to have an unusual GAG‐binding specificity, in that it binds with high affinity to, and is activated by, both heparan and dermatan sulfates. There are two naturally occurring, highly truncated variants of HGF/SF. These comprise only the N‐terminus and either the first one (NK1) or two (NK2) of the four Kringle domains of the α‐chain of HGF/SF, and without a β‐chain. Some controversy presently exists as to whether GAG‐binding in HGF/SF requires the N‐terminus alone, or additionally the second Kringle domain.Materials and methods We have developed a protocol for analysing protein–GAG interactions utilizing fluorescently tagged GAG oligosaccharides run in a protein gel mobility shift assay under native associative conditions. The activity of oligosaccharides has been assessed by their ability to stimulate HGF/SF‐mediated activation of signals downstream of the Met receptor in sulfated GAG‐deficient CHO pgsA‐745 cells.Results HS tetrasaccharides and DS hexasaccharides are the minimal binding and activatory species for HGF/SF. The basis for this size difference between HS and DS species is not presently known. However, their ability to efficiently compete with each other does indicate a shared binding site. The three proteins HGF/SF, NK1 and NK2 all display identical GAG‐binding specificities and minimal oligosaccharide‐binding sizes. This suggests that NK1, the smallest variant, contains the entire minimal GAG‐binding functionality of full‐length HGF/SF, and thus the second Kringle domain is not required. Identification of NK1 and tetrasaccharides as the minimal binding partners has allowed us to directly target the binding site on NK1. Fluorescently tagged tetrasaccharides have been crosslinked into the binding site on NK1 using the zero‐length crosslinking methodology. After tryptic digestion, the specific fluorescently tagged peptides can be recovered for subsequent sequencing to locate the GAG‐binding site within the known amino acid sequence of the protein.Discussion Methods have been developed which can help to identify the respective domains on both GAG and protein involved in GAG‐protein recognition. These are relatively easy approaches, applicable to physiological solution conditions and having the advantage of being widely applicable to many protein interactions involving any uronate‐containing GAGs. In addition to HGF/SF, the gel mobility shift assay has also been applied by us to a variety of other diverse proteins.

Effect of New Synthetic Heparin Mimetics on Whole Blood Thrombin Generation In Vivo and In Vitro in Rats

The effect of new heparin mimetics (synthetic oligosaccharides) was studied in vitro with regard to thrombin generation (TG) in rat platelet rich plasma (PRP) and whole blood (WB) and in vivo on stasis-induced venous thrombosis in the rat. TG in PRP and in WB was highly dependent on platelet count and strongly influenced by the haematocrit. The peak of TG appeared to be significantly higher in WB than in PRP whereas the endogenous thrombin potential (ETP) was not significantly different under either condition. The effect of hirudin, the synthetic pentasaccharide SR90107/Org31540 (SP) and heparin were measured on TG in PRP and WB. We then compared the effect of two new synthetic heparin mimetics (SR121903A and SanOrg123781) with potent and comparable antithrombin (AT) mediated activity against factor Xa and thrombin. These two compounds were made of a pentasaccharide with a high affinity to AT, prolonged at the non-reducing end by an oligosaccharide chain recognised by thrombin. In SR121903A, the charge density and charge distribution was analogous to that of heparin whereas in SanOrg123781 the charges were only located on the last 5 saccharides of the non-reducing end of the molecule. In PRP and in WB, SR121903A acted on the lag time and on the AUC whereas SanOrg123781 inhibited thrombin formation with no effect on the lag time. SanOrg123781 was more potent in inhibiting TG than SR121903A. This difference was due to the structures of the compounds that differed in their ability to be neutralised by platelet factor 4. The antithrombotic effect of the two compounds was examined in a venous thrombosis model in rats. We observed that SanOrg123781 was more active than SR121903A and heparin. Taken together, these results indicate that the activity of oligosaccharides is greatly influenced by the global charge density of the molecule and show that SanOrg123781 is a potent and promising antithrombotic drug candidate.

Putative biological action of oligosaccharides on enzymes involved in cell-wall development

Introduction Primary plant cell wall is synthesized around protoplast and its architecture is determined by a complex balance in the synthesis of several polysaccharides and glycoproteins which form an interwoven network organized around cellulose microfibrils [ 13. Therefore deposition and synthesis of cell-wall material must accompany cell progressive enlargement, and this necessitates a permanent rearrangement of the already deposited material and of the newly synthesized polymers. The chemical and biological nature of the rearrangements that occur within a given constituent polymer or between polymers, the site of their occurrence within the cell wall, and the physical, physiological and biochemical factors that control them, are still not clearly understood. Among the regulatory processes that control cell expansion, auxin-induced growth [2] involves a proton extrusion into the apoplast which may selectively activate wall-associated hydrolases with low pH optima [3]. Cleavage of hemicelluloses, especially xyloglucans (XGs), which are the predominant hemicelluloses in the primary wall of higher plants, has been observed in auxin-treated and acid-treated pea stems [4,5]. This degradation by wall-bound enzymes may have several consequences that serve cell-wall rearrangement. It may result in the breakage of XG interconnections between microfibrils [ 51, thus accounting for wall loosening, and it may at the same time result in the release of biologically active fragments with various lengths and structures. These biologically active oligosaccharides belong to the so-called oligosaccharins, which all possess signalling and regulatory activities [6].