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Applied Microbiology and Biotechnology Mar 2013Epilactose (4-O-β-D-galactopyranosyl-D-mannose), an epimer of lactose, is a rare disaccharide existing extremely small quantities in heat-treated milk, in which... (Review)
Review
Epilactose (4-O-β-D-galactopyranosyl-D-mannose), an epimer of lactose, is a rare disaccharide existing extremely small quantities in heat-treated milk, in which epilactose is produced by non-enzymatic catalysis from lactose. This disaccharide is a kind of non-digestible carbohydrate, has a good prebiotic effect, and promotes intestinal mineral absorption. This article presents a review of recent studies on epilactose formation in food system, qualitative and quantitative analysis, and its physiological functions. In addition, the biochemical properties and kinetic parameters of the epilactose-producing enzyme, cellobiose 2-epimerase, are compared, and the biotechnological production of epilactose from lactose is reviewed.
Topics: Animals; Biotechnology; Carbohydrate Epimerases; Disaccharides; Humans; Intestines; Minerals; Prebiotics
PubMed: 23318840
DOI: 10.1007/s00253-013-4687-2 -
The Biochemical Journal Apr 19791. Preparations of heparin and heparan sulphate were degraded with HNO2. The resulting disaccharides were isolated by gel chromatography, reduced with either NaBH4 or...
1. Preparations of heparin and heparan sulphate were degraded with HNO2. The resulting disaccharides were isolated by gel chromatography, reduced with either NaBH4 or NaB3H4 and were then fractionated into non-sulphated, monosulphated and disulphated species by ion-exchange chromatography or by paper electrophoresis. The non-sulphated disaccharides were separated into two, and the monosulphated disaccharides into three, components by paper chromatography. 2. The uronic acid moieties of the various non- and mono-sulphated disaccharides were identified by means of radioactive labels selectively introduced into uronic acid residues (3H and 14C in D-glucuronic acid, 14C only in L-iduronic acid units) during biosynthesis of the polysaccharide starting material. Labelled uronic acids were also identified by paper chromatography, after liberation from disaccharides by acid hydrolysis or by glucuronidase digestion. Similar procedures, applied to disaccharides treated with NaB3H4, indicated 2,5-anhydro-D-mannitol as reducing terminal unit. On the basis of these results, and the known positions and configurations of the glycosidic linkages in heparin, the two non-sulphated disaccharides were identified as 4-O-(beta-D-glucopyranosyluronic acid)-2,5-anhydro-D-mannitol and 4-O-(alpha-L-idopyranosyluronic acid)-2,5-anhydro-D-mannitol. 3. The three monosulphated [1-3H]anhydromannitol-labelled disaccharides were subjected to Smith degradation or to digestion with homogenates of human skin fibroblasts, and the products were analysed by paper electrophoresis. The results, along with the 1H n.m.r. spectra of the corresponding unlabelled disaccharides, permitted the allocation of O-sulphate groups to various positions in the disaccharides. These were thus identified as 4-O-(beta-D-glucopyranosyl-uronic acid)-2,5-anhydro-D-mannitol 6-sulphate, 4-O-(alpha-L-idopyranosyluronic acid)-2,5-anhydro-D-mannitol 6-sulphate and 4-O-(alpha-L-idopyranosyluronic acid 2-sulphate)-2,5-anhydro-D-mannitol. The last-mentioned disaccharide was found to be a poor substrate for the iduronate sulphatase of human skin fibroblasts, as compared with the disulphated species, 4-O-(alpha-L-idopyranosyluronic acid 2-sulphate)-2,5-anhydro-D-mannitol 6-sulphate. 4. The identified [1-3H]anhydromannitol-labelled disaccharides were used as reference standards in a study of the disaccharide composition of heparins and heparan sulphates. Low N-sulphate contents, most pronounced in the heparin sulphates, were associated with high ratios of mono-O-sulphated/di-O-sulphated (N-sulphated) disaccharide units, and in addition, with relatively large amounts of 2-sulphated L-iduronic acid residues bound to C-4 of N-sulpho-D-glucosamine units lacking O-sulphate substituents.
Topics: Chemical Phenomena; Chemistry; Chromatography, Paper; Disaccharides; Electrophoresis, Paper; Fibroblasts; Glycosaminoglycans; Heparin; Heparitin Sulfate; Magnetic Resonance Spectroscopy; Sulfates
PubMed: 157737
DOI: 10.1042/bj1790077 -
Glycoconjugate Journal Feb 2018Fucosylated oligosaccharides have an important role in maintaining a healthy immune system and homeostatic gut microflora. This study employed a commercial...
Fucosylated oligosaccharides have an important role in maintaining a healthy immune system and homeostatic gut microflora. This study employed a commercial β-galactosidase in the production of fucose-containing galacto-oligosaccharides (fGOS) from lactose and fucose. The production was optimized using experiment design and optimal conditions for a batch production in 3-liter scale. The reaction product was analyzed and the produced galactose-fucose disaccharides were purified. The structures of these disaccharides were determined using NMR and it was verified that one major product with the structure Galβ1-3Fuc and two minor products with the structures Galβ1-4Fuc and Galβ1-2Fuc were formed. Additionally, the product composition was defined in more detail using several different analytical methods. It was concluded that the final product contained 42% total monosaccharides, 40% disaccharides and 18% of larger oligosaccharides. 290 μmol of fGOS was produced per gram of reaction mixture and 37% of the added fucose was bound to fGOS. The fraction of fGOS from total oligosaccharides was determined as 44%. This fGOS product could be used as a new putative route to deliver fucose to the intestine.
Topics: Disaccharides; Fucose; Galactose; Glycosylation; Oligosaccharides; beta-Galactosidase
PubMed: 28905280
DOI: 10.1007/s10719-017-9794-3 -
Carbohydrate Research Aug 1998A synthesis of the disaccharide recently isolated from jojoba beans, 2-O-alpha-D-galactopyranosyl-D-chiro-inositol, has been achieved. The suitably protected...
A synthesis of the disaccharide recently isolated from jojoba beans, 2-O-alpha-D-galactopyranosyl-D-chiro-inositol, has been achieved. The suitably protected chiro-inositol unit was prepared by an enantiospecific synthesis from L-xylose utilizing SmI2-mediated pinacol coupling as a key step.
Topics: Carbohydrate Conformation; Disaccharides; Indicators and Reagents; Models, Molecular; Seeds; Stereoisomerism; Sugar Acids; Xylose
PubMed: 9794077
DOI: 10.1016/s0008-6215(98)00168-2 -
FEMS Immunology and Medical Microbiology Apr 2007Incubation in the presence of structurally modified disaccharides altered the in vitro attachment of Yersinia pestis GB to three human respiratory epithelial cell lines....
Incubation in the presence of structurally modified disaccharides altered the in vitro attachment of Yersinia pestis GB to three human respiratory epithelial cell lines. Each disaccharide resulted in decreased attachment to the alveolar epithelial (A549) cell line. The best inhibitor of attachment for each cell line was the benzylated derivative of Galbeta1-4GalNAc. Highly negatively charged saccharides were efficient inhibitors, particularly for the bronchial epithelial (BEAS2-B) cell line. The data indicate that targeted modification of receptor ligands could offer a novel therapeutic preventing Y. pestis attachment to host cells.
Topics: Anti-Bacterial Agents; Bacterial Adhesion; Cell Line; Disaccharides; Epithelial Cells; Humans; Molecular Structure; Yersinia pestis
PubMed: 17316368
DOI: 10.1111/j.1574-695X.2007.00220.x -
Proceedings of the National Academy of... May 1995The activation of T cells by antigens or mitogens leads to the secretion of cytokines and enzymes that shape the inflammatory response. Among these molecular mediators...
The activation of T cells by antigens or mitogens leads to the secretion of cytokines and enzymes that shape the inflammatory response. Among these molecular mediators of inflammation is a heparanase enzyme that degrades the heparan sulfate scaffold of the extracellular matrix (ECM). Activated T cells use heparanase to penetrate the ECM and gain access to the tissues. We now report that among the breakdown products of the ECM generated by heparanase is a trisulfated disaccharide that can inhibit delayed-type hypersensitivity (DTH) in mice. This inhibition of T-cell mediated inflammation in vivo was associated with an inhibitory effect of the disaccharide on the production of biologically active tumor necrosis factor alpha (TNF-alpha) by activated T cells in vitro; the trisulfated disaccharide did not affect T-cell viability or responsiveness generally. Both the in vivo and in vitro effects of the disaccharide manifested a bell-shaped dose-response curve. The inhibitory effects of the trisulfated disaccharide were lost if the sulfate groups were removed. Thus, the disaccharide, which may be a natural product of inflammation, can regulate the functional nature of the response by the T cell to activation. Such a feedback control mechanism could enable the T cell to assess the extent of tissue degradation and adjust its behavior accordingly.
Topics: Animals; Carbohydrate Sequence; Cattle; Cell Survival; Chromatography, Gel; Cornea; Disaccharides; Endothelium; Extracellular Matrix; Feedback; Female; Glucuronidase; Glycoside Hydrolases; Heparin; Hypersensitivity, Delayed; Inflammation; Mice; Mice, Inbred BALB C; Models, Immunological; Molecular Sequence Data; Spectrometry, Mass, Fast Atom Bombardment; T-Lymphocytes; Tumor Necrosis Factor-alpha
PubMed: 7761444
DOI: 10.1073/pnas.92.11.5037 -
Carbohydrate Research Oct 2014Hellecaucaside A, a new disaccharide nucleoside featuring a 2'-O-α-D-ribofuranosyluridine skeleton and a 4-hydroxybenzoyl group at the 5' position, was isolated from...
Hellecaucaside A, a new disaccharide nucleoside featuring a 2'-O-α-D-ribofuranosyluridine skeleton and a 4-hydroxybenzoyl group at the 5' position, was isolated from the underground part of Helleborus caucasicus. The structure of the compound was elucidated by means of chemical degradation and spectroscopic analyses, such as 1D/2D NMR, chiral-GC, and HRMS. The total synthesis of hellecaucaside A and its β-anomer was accomplished, unequivocally confirming the structure of the natural product.
Topics: Carbohydrate Conformation; Chemistry Techniques, Synthetic; Disaccharides; Helleborus; Nucleosides; Stereoisomerism; Uridine
PubMed: 25240187
DOI: 10.1016/j.carres.2014.06.027 -
Carbohydrate Research Sep 2011d-Glucuronate and l-iduronate-containing disaccharides related to the antithrombin-binding domain of heparin were prepared. The carboxylic function of the uronic acid...
d-Glucuronate and l-iduronate-containing disaccharides related to the antithrombin-binding domain of heparin were prepared. The carboxylic function of the uronic acid unit was formed on a disaccharide level in the case of the glucuronate, while on a monosaccharide level in the case of the iduronate derivatives. Synthesis of their sulfonic acid analogues was carried out analoguosly applying sulfonatomethyl-containing acceptors in the form of either salts or methyl esters. Significant difference could be observed in the methyl ether formation reactions of the sulfonatomethyl-containing uronate disaccharides and the non-sulfonic acid uronates.
Topics: Antithrombin III; Carbohydrate Sequence; Disaccharides; Heparin; Iduronic Acid
PubMed: 21798526
DOI: 10.1016/j.carres.2011.06.021 -
Organic Letters May 2000[equation--see text] A protected ezomycin octosyl nucleoside was glycosylated at O-6' with a protected ezoaminuroic acid donor to afford, following several functional...
[equation--see text] A protected ezomycin octosyl nucleoside was glycosylated at O-6' with a protected ezoaminuroic acid donor to afford, following several functional group modifications, the title compound 1 ( identical with 4-desamino-4-oxoezomycin A(2)).
Topics: Aminoglycosides; Anti-Bacterial Agents; Antifungal Agents; Disaccharides; Glycosylation; Indicators and Reagents; Models, Molecular; Molecular Conformation; Nucleosides
PubMed: 10814455
DOI: 10.1021/ol005696f -
Carbohydrate Research Jan 2014A rat monoclonal antibody 9D4 raised against the cell surface N-glycan of the parasite Trichinella spirallis protects rats against further infection. The terminal...
A rat monoclonal antibody 9D4 raised against the cell surface N-glycan of the parasite Trichinella spirallis protects rats against further infection. The terminal disaccharide β-d-Tyvp(1→3)β-d-GalNAcp (2) represents the immunodominant portion of the antigenic determinant. Chemical mapping of the antibody binding site by functional group modification employing monodeoxy and mono-O-methyl congeners identified key polar contacts and topography of the bound disaccharide. We report here a comparison of the chemical mapping studies with the antigen topography inferred from saturation transfer difference (STD) NMR experiments. During chemical mapping several congeners of compound 2 showed substantially enhanced binding. Pairing of these functional group modifications to create derivatives 6 and 7 did not show additive free energy gains and STD NMR data point to small variations in mode of binding as a probable cause. Improved syntheses of disaccharides 2-7 are reported.
Topics: Animals; Antibodies, Monoclonal; Binding Sites, Antibody; Disaccharides; Epitopes; Magnetic Resonance Spectroscopy; Rats; Surface Properties; Trichinella spiralis
PubMed: 24239604
DOI: 10.1016/j.carres.2013.10.012