SEARCH · Search PubMed

Results for “MONOSACCHARIDES”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

SourceResearch connectionFrom yearThrough year

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 37 records · Page 2Linked to original sources

PubMed1984

The production of free radicals during the autoxidation of monosaccharides by buffer ions.

The production of free radicals during the autoxidation of simple monosaccharides at 37 degrees has been studied by the electron spin resonance (e.s.r.) technique of spin trapping. In the presence of the spin trap 5,5-dimethyl-1-pyrroline N-oxide (DMPO), monosaccharides undergoing autoxidation produced hydroxyl and 1-hydroxyalkyl radical-derived spin adducts, indicating that hydroxyl and hydroxyalkyl free-radicals are involved in the autoxidation of monosaccharides. The pH profile for the production of free radicals from monosaccharides undergoing autoxidation revealed the formation of both hydroxyl and hydroxyalkyl radicals at relatively high pH, whereas at low pH, only the formation of hydroxyalkyl radicals was observed; the transition between these routes for the production of free radicals occurred at pH 8.0-8.5. Glycolaldehyde, glyceraldehyde, dihydroxyacetone, and erythrose are relatively rapidly enolised (to an ene-diol) and autoxidised with the concomitant production of free radicals. Ribose and glucose enolise and autoxidise very slowly without detectable production of free radicals. A comparison of the pH profiles of the rates of enolisation and the pH dependence of the production of free radicals from glyceraldehyde during autoxidation suggests that a change in reaction mechanism occurs at pH 8.2. Below pH 8.2, the rates of enolisation and autoxidation increase with increasing pH, with a concomitant increase in the formation of hydroxyalkyl spin-adducts. Above pH 8.2, glyceraldehyde undergoing autoxidation shows a much higher rate of enolisation than of autoxidation and, although the formation of hydroxyalkyl radicals is decreased, the production of hydroxyl radicals is also observed. A free-radical mechanism for the autoxidation of monosaccharides is proposed, to account for the pH-dependent characteristics of the production of free radicals and the relationships between the production of free radicals, autoxidation, and enolisation of the monosaccharides.

Buffers↗

PubMed1982

Influence of monosaccharides on the infection of vertebrate cells by Trypanosoma cruzi and Toxoplasma gondii.

The effect of 9 monosaccharides which constitute cell surface carbohydrates on the infection of bovine embryonic skin and muscle (BESM) cells by Trypanosoma cruzi trypomastigotes and Toxoplasma gondii tachyzoites was assayed. Most of the monosaccharides tested stimulated the infection of BESM cells by T. gondii; none of the monosaccharides were inhibitory. In contrast (at a concentration of 50 mM or greater) the monosaccharides inhibited non-specifically the infection of BESM cells by T. cruzi trypomastigotes whereas the other 8 monosaccharides were ineffective. The inhibition was due to an effect on the trypomastigotes and not on the vertebrate cells. It is proposed that there is a wheat-germ agglutinin-like lectin on the T. cruzi trypomastigote surface which recognizes and attaches to an N-acetylglucosamine-containing receptor on the vertebrate cell surface prior to infection. Infection of vertebrate cells by T. gondii tachyzoites appears to be mediated by other cell surface components. If monosaccharides are involved in infection by tachyzoites, they are ones not commonly found on animal cell surfaces. Alternatively, infection of vertebrate cells by T. cruzi and T. gondii is effected by different mechanisms.

Acetylglucosamine↗

PubMed2000

Monosaccharides are not detected in whole or isthmic bovine oviductal fluid collected throughout the estrous cycle, as analyzed by HPLC.

In the bovine oviduct, monosaccharides may play a role in the preparation of gametes for fertilization. Sperm are sequestered in the isthmic region of the oviduct where capacitation, requisite biochemical changes in sperm membranes, may take place. Retention of spermatozoa in the oviductal isthmus is dependent on a carbohydrate recognition system between oviductal epithelium and sperm membrane lectins. The monosaccharide, fucose, has been found to be important to this recognition system. However, both gametes and epithelium are also bathed in oviductal fluid (ODF), and fucose or other monosaccharides may be constituents of ODF and so may be important to sperm binding to oviductal epithelium and subsequent preparation for fertilization. In this study, ODF from dairy cows was analyzed by HPLC for the presence of 5 monosaccharides (fucose, galactose, glucosamine, mannose and xylose). Both whole ODF, collected by cannulation of the entire oviduct of 1 cow over a complete estrous cycle, and regional staged ODF, collected and pooled from 13 cows from the isthmic region only at estrus, were analyzed. We report negligible concentrations of all 5 monosaccharides in both types of ODF analyzed. Because the detection limit of our assay was 10(8) times lower than fucose concentrations found to be physiologically important in earlier in vitro studies, we conclude that bovine ODF does not contain physiologically active levels of free fucose or other, similar monosaccharides at any time of the estrous cycle.

Animals↗

PubMed1983

Determination and apparent digestibility of neutral detergent fiber monosaccharides in women.

The neutral monosaccharides in neutral detergent fiber (NDF) extracted from low and high cellulose diets and from feces excreted by seven women consuming the same diet were determined. In addition, apparent digestibilities of the NDF neutral monosaccharides during consumption of both diets were compared. Diets were of constant daily composition and differed only in that the high fiber diet contained 16 g/day of Solka Floc. NDF residues from food and feces were hydrolyzed by the Saeman procedure and the neutral saccharides measured by high performance liquid chromatography. More than 75% of the food NDF from both diets was glucose. Mean fecal NDF was 77% glucose during feeding of the low fiber diet, 89% glucose during the high fiber diet. Xylose was the next most common monosaccharide, accounting for 6-16% of the monosaccharides detected in food and fecal NDF. Concentrations of the other sugars, arabinose, cellobiose, mannose, galactose and rhamnose, ranged from 1 to 6%. Apparent digestibility of the sugars decreased significantly when Solka Floc was consumed: glucose from 85 to 48%; xylose from 76 to 57%; arabinose 89 to 73%; and mannose 86 to 43%. These data indicate that the monosaccharides in NDF from a representative low fiber diet are degraded extensively in the gut, and that adding Solka Floc to the diet decreases the digestibility of all fiber-derived monosaccharides.

Adult↗

PubMed1984

Transient monosaccharide intolerance in infants with acute and protracted diarrhoea.

A retrospective clinical study was done of 38 infants with temporary monosaccharide intolerance who were admitted to hospital between November 1976 and August 1978. There were two clinical groups. Group 1 consisted of 31 infants who developed monosaccharide intolerance as a sequela to acute gastroenteritis (i.e., 4% of infants admitted with acute gastroenteritis). Rotavirus was the cause of gastroenteritis in 64% of cases of monosaccharide intolerance. Monosaccharide intolerance was easily managed by dietary manipulations and lasted a mean of 2.5 days. Group 2 consisted of seven infants who developed monosaccharide intolerance during the course of protracted diarrhoea. The monosaccharide intolerance lasted up to 70 days, with a mean of 21 days, and required a period of total bowel rest followed often by complicated dietary manipulation.

Acute Disease↗

PubMed1996

A strategy for chromatographic and structural analysis of monosaccharide species from glycoproteins.

A general strategy for the chromatographic and structural analysis of the monosaccharide species fucose (Fuc), N-acetylgalactosamine (GalNAc), N-acetylglucosamine (GlcNAc), galactose (Gal), glucose (Glc), mannose (Man), N-acetylneuraminic acid (NANA) present in glycoproteins is described. Qualitative and quantitative aspects for the separation of these glycoprotein monosaccharides (monosaccharide species) using ligand-exchange chromatography (LEC) and high pH anion-exchange chromatography (HPAEC) in combination with pulsed-amperometric detection (PAD), refractive index (RI) and ultraviolet (UV) monitoring are discussed in detail. The conditions for the acidic hydrolysis of glycoproteins and for the liquid chromatographic analyses of glycoprotein monosaccharides using HPAEC and LEC technique were optimised. Furthermore, the characterisation of glycoproteins according to their purity and molecular mass connected with a comparison to biomolecules that are not glycosylated or whose extent of glycosylation is low was carried out by means of matrix-assisted laser-desorption ionisation mass spectrometry (MALDI-MS). The identification of glycoprotein monosaccharides using an on-line coupling liquid chromatography mass spectrometry (LC-MS/MS) was performed by means of their characteristic "quasi molecule ions" such as (M + NH(4))(+) and (2M + NH(4))(+). The different chromatographic and structural methods used in combination with each other were applied to characterise and determine the monosaccharide species of fetuin and a membrane glycoprotein fraction.

Journal Article↗

PubMed1979

[Relationship between Na+ and monosaccharide influx across the microvilli membrane depending on the energy state of the intestinal mucosa wall].

1. An energy dependence of the Na+ influx and of the "extra-Na+ influx" across the microvilli membrane was demonstrated in an in vitro preparation of the rat jejunum by adjustment of low ATP/ADP quotients. The monosaccharide influx does not show this dependence. 2. The similar relationship of monosaccharide-dependent Na+ influx and Na+ influx without monosaccharide with the energy state in the mucosa cells suggests a common control system. 3. A constant stoichiometry between monosaccharide and "extra-Na+ influx" can be maintained only under constant intracellular conditions. 4. The changes of the Na+ and K+ influxes by so-called Na+ dependently transported monosaccharides correspond to those which can be elicited by lowering the ATP/ADP ratio in the in vitro preparation. 5. A mechanism is discussed in which an ATP-utilizing reaction is stimulated in the microvilli owing to the monosaccharide transport, thus locally discontinuing the condition for uncoupling of an (Na, K)-ATPase and eliciting an "extra-Na+ influx".

Adenosine Diphosphate↗

PubMed1995

Monosaccharide composition analysis of oligosaccharides and glycoproteins by high-performance liquid chromatography.

A simple and sensitive high-performance liquid chromatography (HPLC)-based method for complete monosaccharide composition analysis of oligosaccharides and glycoproteins is described. In this method, an oligosaccharide or glycoprotein is first hydrolyzed using an optimized method to give the constituent monosaccharides, which are subsequently labeled with 1-phenyl-3-methyl-5-pyrazolone (PMP) as previously described by Honda et al. (Anal, Biochem. 180, 351-357, (1989)). The labeled monosaccharides are separated by reverse-phase HPLC using a column developed especially for this purpose, monitored by uv absorbance at 245 nm, and quantitated by their integration values relative to standards. Sialic acids are acid-labile keto-sugars. They are, therefore, released with neuraminidases or by mild acid hydrolysis and then converted with neuraminic acid aldolase to their corresponding mannosamine derivatives, which are then PMP-labeled, separated, and quantitated as described above. Individual sialic acids including N-acetyl and N-glycolyl neuraminic acids are well resolved and quantitated by this method. This method has proven to be highly sensitive, requiring only 1 pmol for reliable detection. Quantitative analysis of neutral and amino sugars from both oligosaccharide and glycoprotein samples can be achieved using one acid hydrolysis and a set of equal molar monosaccharide standards. Similarly, quantitation of sialic acids works equally well with both free oligosaccharide and glycoprotein samples. Monosaccharide compositions of oligosaccharides and glycoproteins determined by this method were found to be highly accurate.

Antipyrine↗

PubMed1984

The oxidation of oxyhaemoglobin by glyceraldehyde and other simple monosaccharides.

Glyceraldehyde and other simple monosaccharides oxidize oxyhaemoglobin to methaemoglobin in phosphate buffer at pH 7.4 and 37 degrees C, with the concomitant production of H2O2 and an alpha-oxo aldehyde derivative of the monosaccharide. Simple monosaccharides also reduce methaemoglobin to ferrohaemichromes (non-intact haemoglobin) at pH 7.4 and 37 degrees C. Carbonmonoxyhaemoglobin is unreactive towards oxidation by autoxidizing glyceraldehyde. Free-radical production from autoxidizing monosaccharides with haemoglobins was observed by the e.s.r. technique of spin trapping with the spin trap 5,5-dimethyl-l-pyrroline N-oxide. Hydroxyl and l-hydroxyalkyl radical production observed from monosaccharide autoxidation was quenched in the presence of oxyhaemoglobin and methaemoglobin. The haemoglobins appear to quench the free radicals by reaction with the free radicals and/or the ene-diol precursor of the free radical.

Chemical Phenomena↗

PubMed1999

Effects of ethanol ingestion on sperm monosaccharides and fertility.

Chronic alcohol abuse is often associated with reproductive disorders. Sperm monosaccharides play an indispensable role in sperm-egg interactions and fertilization. Ethanol (3 g/kg body weight as 25%, v/v) was given by gastric intubation twice daily for 30 days while in another group, rats which had been treated with ethanol were withdrawn from treatment for a further period of 30 days, in order to assess the reversibility of the ethanol-induced effects. Epididymal ethanol content, sperm monosaccharides and the fertility of ethanol treated and ethanol withdrawn rats were assessed. Ethanol ingestion caused a significant decrease in sperm monosaccharides suggesting defective glycosylation of sperm surface proteins. Sperm monosaccharides and fertility were returned to normal following the withdrawal of ethanol. Ethanol-induced changes in sperm monosaccharides may be one of the reasons for the reduced fertility of ethanol treated rats.

Animals↗

PubMed1998

Hexose transport in growing petunia pollen tubes and characterization of a pollen-specific, putative monosaccharide transporter.

We investigated the molecular and physiological processes of sugar uptake and metabolism during pollen tube growth and plant fertilization. In vitro germination assays showed that petunia (Petunia hybrida) pollen can germinate and grow not only in medium containing sucrose (Suc) as a carbon source, but also in medium containing the monosaccharides glucose (Glc) or fructose (Fru). Furthermore, high-performance liquid chromatography analysis demonstrated a rapid and complete conversion of Suc into equimolar amounts of Glc and Fru when pollen was cultured in a medium containing 2% Suc. This indicates the presence of wall-bound invertase activity and uptake of sugars in the form of monosaccharides by the growing pollen tube. A cDNA designated pmt1 (petunia monosaccharide transporter 1), which is highly homologous to plant monosaccharide transporters, was isolated from petunia. Pmt1 belongs to a small gene family and is expressed specifically in the male gametophyte, but not in any other vegetative or floral tissues. Pmt1 is activated after the first pollen mitosis, and high levels of mRNA accumulate in mature and germinating pollen. A model describing the transport of sugars to the style, the conversion of Suc into Glc and Fru, and the active uptake by a monosaccharide transporter into the pollen tube is presented.

Amino Acid Sequence↗

PubMed1990

Sugar-mediated induction of Agrobacterium tumefaciens virulence genes: structural specificity and activities of monosaccharides.

The virulence genes of Agrobacterium tumefaciens are induced by specific plant phenolic metabolites and sugars (G. A. Cangelosi, R. G. Ankenbauer, and E. W. Nester, Proc. Natl. Acad. Sci. USA, in press). In this report, monosaccharides, derivatives, and analogs which induce the vir regulon have been identified and the structural requirements for monosaccharide-mediated induction have been determined. Pyranose sugars with equatorial hydroxyls at C-1, C-2, and C-3 displayed strong vir gene-inducing activity; the C-4 hydroxyl could be epimeric and a wide variety of substitutions at C-5 were permissible. The acidic monosaccharide derivatives D-galacturonic acid and D-glucuronic acid were the strongest inducers among the monosaccharides tested. Eight of the 11 inducing compounds are known plant metabolites, and 7 are monomers of major plant cell wall polysaccharides. A role for monosaccharides and plant phenolic compounds as wound-specific plant metabolites which signal the ChvE/VirA/VirG regulatory system is proposed.

Bacterial Proteins↗

PubMed2002

Intestinal permeability and carrier-mediated monosaccharide absorption in preterm neonates during the early postnatal period.

Immaturity of intestinal epithelial barrier function and absorptive capacity may play a role in the pathophysiology of intestinal complications in preterm neonates during the early postnatal period. We determined the intestinal permeability and carrier-mediated absorption of monosaccharides in preterm neonates during the first 2 wk after birth. Fifty-nine preterm neonates born between 25 and 32 wk gestation were included within 24 h of birth. Neonates received exclusively parenteral nutrition during the first 7 d after birth; enteral feeding was initiated at d 8. An intestinal permeability-absorption test was performed at 1, 4, 7, and 14 d after birth. The lactulose-to-rhamnose ratio was determined as a marker of intestinal permeability. Urinary excretion percentages of D-xylose and 3-O-methyl-D-glucose were determined as markers of passive and active carrier-mediated monosaccharide absorption, respectively. Intestinal permeability transiently increased between d 1 and 7 in all neonates (p < 0.05). Carrier-mediated monosaccharide absorption increased between d 1 and 14 in neonates of 28-30 wk (p < 0.05) to the level observed in the neonates of 30-32 wk gestation. In neonates <28 wk, intestinal permeability at d 7 was higher (p < 0.05) and carrier-mediated monosaccharide absorption at d 14 was lower (p < 0.01) as compared with neonates >or=28 wk. The barrier function of the intestinal epithelium transiently decreases during the first week after birth in preterm neonates who are not enterally fed. Diminished barrier function and low monosaccharide absorptive capacity, particularly in neonates <28 wk, may predispose these patients to the development of intestinal complications during the early postnatal period.

Female↗

PubMed1998

[High performance liquid chromatographic analysis of monosaccharide composition in lacquer polysaccharide from sap of lac tree].

This paper reports the separation and determination of monosaccharide composition in lacquer polysaccharide (LPS) by HPLC. The five monosaccharides were analyzed on microBondapak NH2 column (300 mm x 7.8 mm i.d. 10 microns) and refractive index detection. The mobile phase was CH3CN-H2O-CH3OH (70:25:5, V/V) flowing at a rate of 1.6 mL/min. These monosaccharides were identified by their retention times and quantitatively determined by their peak areas. LPS samples were hydrolysed with 2.0 mol/L CF3COOH. The linear correlation coefficients were all over 0.9953. The average recoveries of monosaccharides ranged 98.8%-103.6% and relative standard deviations were below 5%. The method is simple, rapid, precise, and has been used satisfactorilly for analysis of the monosaccharides hydrolyzed from LPS, which were isolated from sap of three kinds of Lac tree (Maoba Damu, Maoba Xiaomu and Jianshi) in Hubei province.

Chromatography, High Pressure Liquid↗

PubMed2003

[Comparison of Echinops species on the basis of the monosaccharide composition of polysaccharides].

The goal of our investigation was to compare the monosaccharide composition of polysaccharides of different Echinops species. The determination of monosaccharid composition was made after Taylor reduction, acidic hydrolysis, reduction with sodium borohydride and acetylation in pyridine/aceticanhydride as alditol-acetates with gas chromatographic analysis. 4-O-methyl-glucuronic acid was found in all studied species. The best similarity was found in the case of the monosaccharide composition of E. ruthenicus and E. exaltatus where rhamnose and arabinose are the main monosaccharides and 4-O-methyl-glucuronic acid is the uronic acid component. The main monosaccharides are glucose in E. orientalis and glucose and mannose in E. commutatus. Glucuronic acid is the uronic acid component in both species.

Asteraceae↗

PubMed1969

Mitochondrial autonomy: incorporation of monosaccharides into glycoprotein by isolated mitochondria.

Isolated intact mitochondria selectively incorporate monosaccharides from nucleotide diphosphate monosaccharides into protein. Fucose, mannose, glucose, and galactose were incorporated by the mitochondria into glycoprotein; xylose was not. Structural integrity of the mitochondria was not necessary for the incorporation of monosaccharide into glycoprotein; mitochondria broken by homogenization also incorporated monosaccharide. The monosaccharides incorporated into glycoprotein were localized in the inner mitochondrial membranes, the same membranes which contain the protein into which leucine is incorporated by the isolated mitochondria.

Animals↗

PubMed2001

Gas chromatography/combustion/isotope-ratio-monitoring mass spectrometric analysis of methylboronic derivatives of monosaccharides: a new method for determining natural 13C abundances of carbohydrates.

Monosaccharides were derivatized using methylboronic acid and N,O-bis(trimethylsilyl)trifluoroacetamide (BSTFA), and the delta13C values of these derivatives measured by gas chromatography/combustion/isotope-ratio-monitoring mass spectrometry to determine the original 13C-content of the monosaccharides. Comparison with the measured off-line delta13 values of the monosaccharides shows that no fractionation in 13C takes place during derivatization. The methylboronic derivatization method has proven to be a new method for natural abundance isotopic analysis of intact monosaccharides (arabinose, xylose, fucose, fructose and glucose). The method is rapid, does not involve isotopic fractionation during derivatization, and gives more precise delta13C values than other methods reported. The method was successfully applied to determine the delta13C value of glucose of the freshwater alga Scenedesmus communis.

Arabinose↗

PubMed1988

Monosaccharide analysis of glycoconjugates by anion exchange chromatography with pulsed amperometric detection.

The method of anion exchange chromatography followed by pulsed amperometric detection (AE-PAD; Johnson, D. C., and Polta, T. Z. (1986) Chromatogr. Forum 1, 37-44) has been applied to the compositional analysis of glycoconjugates. Using 22 mM NaOH as a column effluent, underivatized fucose, galactosamine, glucosamine, galactose, glucose, and mannose were readily separated in 15 min at a flow rate of 1 ml/min. The limit of quantification of the monosaccharides was better than 100 pmol (signal to noise ratio 184:1). AE-PAD was employed to quantify the monosaccharides of several glycoproteins, glycopeptides, and oligosaccharides after hydrolysis with 2 M trifluoroacetic acid. Both neutral and amino sugars could be rapidly estimated in a single chromatographic step using AE-PAD. Complete release of N-acetylglucosamine required more vigorous hydrolysis conditions (Lee, Y. C. (1972) in Methods in Enzymology (Ginsburg, V., Ed.), Vol. 28, pp. 63-73, Academic Press, New York). In both glycopeptides and oligosaccharides, approximately one less residue of Man than predicted was determined. Both AE-PAD and liquid chromatographic analysis of borate-monosaccharide complexes with fluorometric detection (Mikami, H., and Ishida, Y. (1983) Bunseki Kagaku 32, E207-E210) gave similar quantification of mannose and other sugars. The capability of rapid, sensitive quantification of underivitized monosaccharides should facilitate structural analysis of glycoconjugates.

Amino Sugars↗