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Carbohydrate Composition (carbohydrate + composition)
Selected AbstractsEFFECT OF EXTRUSION COOKING AND SODIUM BICARBONATE ADDITION ON THE CARBOHYDRATE COMPOSITION OF BLACK BEAN FLOURSJOURNAL OF FOOD PROCESSING AND PRESERVATION, Issue 2 2002JOSE DE J. BERRIOS ABSTRACT Extrusion cooking and chemical leavening agents such as sodium bicarbonate (NaHCO3), may induce changes in carbohydrate fractions of extruded black bean (Phaseolus vulgaris L.) flours. Bean flours at 20% moisture, with NaHCO3 added at levels from 0.0 to 2.0%, were extruded at a screw speed of 200 rpm. The temperature profile ranged from 23 to 160C. Extruded bean flours with 0.1 to 0.4% added NaHCO3 were selected for sugar analyses based on color and flavor acceptability. The major sugars determined in the bean samples were galactose (0.10%), sucrose (2.08%), and stachyose (2.00%). Extruded samples had an increase in total sugars. Also, an increase in soluble fiber and a decrease of insoluble fiber fractions were observed. Sucrose was the only free sugar which concentration decreased consistently as a result of extrusion processing. Extrusion conditions and the selected levels of NaHCO3 used in this study did not significantly change the oligosaccharide content of the black bean flours. [source] Glycoform characterization of erythropoietin combining glycan and intact protein analysis by capillary electrophoresis , electrospray , time-of-flight mass spectrometryELECTROPHORESIS, Issue 13 2006Elvira Balaguer Abstract Glycosylation of recombinant human erythropoietin (rHuEPO) is a post-translational process that alters biological activity, solubility and lifetime of the glycoprotein in blood, and strongly depends on the type of cell and the cell culture conditions. A fast and simple method providing extensive carbohydrate information about the glycans present in rHuEPO and other glycoproteins is needed in order to improve current methods in drug development or product quality control. Here, an improved method for intact rHuEPO glycoform characterization by CZE-ESI-TOF MS has been developed using a novel capillary coating and compared to a previous study. Both methods allow a fast separation in combination with accurate mass characterization of the single protein isoforms. The novel dynamic coating provides a separation at an EOF close to zero, enabling better separation. This results in an improved mass spectrometric resolution and the detection of minor isoforms. In order to assign an unequivocal carbohydrate composition to every intact glycoform, a CZE-ESI-MS separation method for enzymatically released underivatized N -glycans has been developed. The TOF,MS allows the correct identification of the glycans due to its high mass accuracy and resolution. Therefore, glycan modifications such as acetylation, oxidation, sulfation and even the exchange of OH by NH2 are successfully characterized. Information of the protein-backbone molecular mass has been combined with results from peptide analysis (revealing information about O -glycosylation) and from the glycan analysis, including the detection of as yet undescribed glycans containing four antennae and five sialic acids. This allows an unequivocal assignment of an overall glycosylation composition to the molecular masses obtained for the intact rHuEPO glycoforms. [source] Characterization of glyco isoforms in plasmaderived human antithrombin by on-line capillary zone electrophoresis-electrospray ionization-quadrupole ion trap-mass spectrometry of the intact glycoproteinsELECTROPHORESIS, Issue 13 2004Uwe M. Demelbauer Abstract The carbohydrate structures of five isoforms of ,-AT and two isoforms of ,-AT were determined by applying capillary zone electrophoresis (CZE) on-line coupled to electrospray ionization-mass spectrometry (ESI-MS) using an ion-trap analyzer. For the AT preparations gained from a plasma pool at least semiquantitative information on the isoform-distributions could be gained. Unlike to the commonly used approaches starting from enzymatically treated glycoproteins, this approach deals with intact proteins. The high accuracy of the molecular mass determination obtained by the ion-trap analyzer allows one to calculate and ascertain the carbohydrate composition assuming no variations in the protein moiety of AT and to exclude or confirm the presence of the potential post-translational or other modifications. Therefore, the direct coupling of CZE with ESI-MS does not only represent a fast alternative technique to two-dimensional electrophoresis (2-DE) but serves as a method which provides structural information complementary to that gained from peptide mapping methods. [source] Receptor-mediated phagocytosis of rat macrophages is regulated differentially for opsonized particles and non-opsonized particles containing ,-glucanIMMUNOLOGY, Issue 2 2001Jonathan S. Reichner Summary Experiments were conducted to test the hypothesis that opsonic and non-opsonic phagocytic capacities are differentially regulated by resting and wound-derived macrophages. Furthermore, the phagocytosis of non-opsonized zymosan and ,-glucan particles was quantified to determine whether cells differentially regulate non-opsonic lectinophagocytosis in accordance with the carbohydrate composition of the ligand. In that regard, wound macrophages exhibited profound differential regulation in lectinophagocytosis with a seven-fold increase in phagocytosis of ,-glucan particles following overnight culture but with a relatively modest increase in internalization of mannan-containing zymosan. Cultured peritoneal macrophages increased uptake of both particles similarly. Upon activation with interferon-,/lipopolysaccharide (IFN-,/LPS), wound macrophages selectively suppressed ,-glucan ingestion, while phagocytosis of zymosan particles was unaffected. Lectinophagocytosis was decreased in activated peritoneal macrophages regardless of particle composition and was due in part to a nitric oxide-dependent mechanism which was without a role in regulation of wound macrophage lectinophagocytosis. Overnight culture of wound macrophages suppressed their capacity for opsonic-dependent phagocytosis independently of activation, whereas suppression of phagocytosis by peritoneal macrophages was activation-dependent. Regulation of all three phagocytic pathways was achieved distinctly by peritoneal and wound-derived macrophages, with changes found in the percentage of resident peritoneal macrophages capable of phagocytosis, whereas the phagocytic capacity of wound macrophages was primarily affected by the number of particles ingested by individual cells. Taken together, these findings demonstrate that the differential regulation of phagocytic pathways encompasses the nature of the phagocytic particle, the site from which macrophages are obtained, their response to activating agents and the mechanism through which the cell population alters its phagocytic potential. [source] Changes in inulin and soluble sugar concentration in artichokes (Cynara scolymus L.) during storageJOURNAL OF THE SCIENCE OF FOOD AND AGRICULTURE, Issue 7 2010Gaëlle Leroy Abstract BACKGROUND: The artichoke (Cynara scolymus L.) accumulates about 50,70 g kg,1 of its fresh weight as inulin-type fructan. Inulin fermentation increases gas production and thereby provokes intestinal discomfort in some people. The present research focuses on the changes in carbohydrate composition occurring in artichoke heads during storage under different conditions (18 °C, 4 °C and 4 °C under polypropylene film packing). RESULTS: Carbohydrate content and composition were determined by anion-exchange high-performance liquid chromatography with pulsed amperometric detection. Storage time caused a decrease in inulin content and an average degree of polymerization, accompanied by an increase of free fructose and sucrose due to depolymerization of inulin. CONCLUSION: Higher-temperature storage and storage without packing induce strong carbohydrate changes. Thereby, eating stored artichoke leads to consumption of an inulin quantity that does not provoke unwanted symptoms related to gas production but sufficient to have a prebiotic effect. Copyright © 2010 Society of Chemical Industry [source] Association of Season and Pasture Grazing with Blood Hormone and Metabolite Concentrations in Horses with Presumed Pituitary Pars Intermedia DysfunctionJOURNAL OF VETERINARY INTERNAL MEDICINE, Issue 5 2010N. Frank Background: Pituitary pars intermedia dysfunction (PPID) is a risk factor for pasture-associated laminitis, which follows a seasonal pattern. Hypothesis: Hormonal responses to season differ between PPID and unaffected horses. Animals: Seventeen horses aged 8,30 years (14 horses , 20 years of age). Methods: Longitudinal observational study. Blood was collected monthly from August 2007 until July 2008 after pasture grazing and again after overnight stall confinement. Blood hormone and metabolite concentrations were measured and pasture grass samples were analyzed to determine carbohydrate content. Analysis of variance analysis for repeated measures was performed. Results: Mean ACTH concentrations varied significantly over time (P < .001), with higher concentrations detected in August, September, and October compared with November,April. Pasture × time effects were detected for glucose and insulin concentrations, with peaks observed in September. Horses were retrospectively allocated to PPID (n = 8) and control (n = 9) groups on the basis of plasma ACTH concentrations. Changes in insulin concentrations over time differed in the PPID group when compared with the control group. Insulin concentrations were positively correlated with grass carbohydrate composition. Conclusions and Clinical Importance: PPID did not affect the timing or duration of the seasonal increase in ACTH concentrations, but higher values were detected in affected horses. Insulin concentrations differed between groups, but hyperinsulinemia was rarely detected. Glucose and insulin concentrations peaked in September when horses were grazing on pasture, which could be relevant to the seasonal pattern of laminitis. [source] Histochemical Analysis of Glycoconjugates in the Skin of a Catfish (Arius Tenuispinis, Day)ANATOMIA, HISTOLOGIA, EMBRYOLOGIA, Issue 1 2010A. Al-Banaw Summary A histochemical study using conventional carbohydrate histochemistry (periodic-acid staining including diastase controls, alcian blue staining at pH 1 and 2.5) as well as using a battery of 14 fluorescein isothiocyanate (FITC)-labelled lectins to identify glycoconjugates present in 10 different areas of the skin of a catfish (Arius tenuispinis) was carried out. The lectins used were: mannose-binding lectins (Con A, LCA and PSA), galactose-binding lectins (PNA, RCA), N -acetylgalactosamine-binding lectins (DBA, SBA, SJA and GSL I), N -acetylglucosamine-binding lectins (WGA and WGAs), fucose-binding lectins (UEA) and lectins which bind to complex carbohydrate configurations (PHA E, PHA L). Conventional glycoconjugate staining (PAS staining, alcian blue at pH 1 and 2.5) showed that the mucous goblet cells contain a considerable amount of glycoconjugates in all locations of the skin, whereas the other unicellular gland type, the club cells, lacked these glycoconjugates. The glycoproteins found in goblet cells are neutral and therefore stain magenta when subjected to PAS staining. Alcian blue staining indicating acid glycoproteins was distinctly positive at pH 1, but gave only a comparable staining at pH 2.5. The mucus of the goblet cells therefore also contains acid glycoproteins rich in sulphate groups. Using FITC-labelled lectins, the carbohydrate composition of the glycoproteins of goblet cells could be more fully characterized. A distinct staining of the mucus of goblet cells was found with the mannose-binding lectins LCA and PSA; the galactosamine-binding lectins DBA, SBA and GLS I; the glucosamine-binding lectin WGA; and PHA E which stains glycoproteins with complex carbohydrate configurations. No reaction occurred with the fucose-binding lectin UEA and the sialic acid-specific lectin SNA. In addition, the galactose-binding lectins PNA and RCA showed only a weak or completely negative staining of the mucus in the goblet cells. The specificity of the lectin staining could be proved by inhibiting binding of the lectins by competitive inhibition with the corresponding sugars. From these data, we can conclude that the mucus produced by the epidermal goblet cells of A. tenuispinis is rich in mannose, N -acetylgalactosamine and N -acetylglucosamine residues. [source] Osmotic adjustment of chickpea (Cicer arietinum) is not associated with changes in carbohydrate composition or leaf gas exchange under droughtANNALS OF APPLIED BIOLOGY, Issue 2 2007P.S. Basu Abstract Genetic differences in osmotic adjustment (OA) have been reported among chickpea (Cicer arietinum) cultivars. In this study eight advanced breeding lines (ABLs) derived from a cross between CTS 60543 (high OA) and Kaniva (low OA) and Tyson (medium OA) and Kaniva, along with the parents, were evaluated for OA, leaf carbohydrate composition and leaf gas exchange under dryland field conditions in India. The water potential (WP) decreased to lower values (less than ,2.5 MPa) in Tyson, M 110 and M 86 than in the other genotypes. With decrease in WP, OA increased by 0.5 MPa in Kaniva and CTS 60543 to 1.3 MPa in M 55. As the decrease in WP varied with genotype, when OA was regressed against WP M 39 and M 55 had greater increases in OA with decrease in WP than the remaining nine genotypes, including the parents. As WP decreased, leaf starch content decreased while total soluble sugars, hexoses and sucrose increased: the decrease in starch was much smaller in M 93 and M 129 than in Tyson and M 51, but genotypic differences could not be detected in the increase in total sugars, hexoses or sucrose. The rates of photosynthesis and transpiration decreased as the WP became more negative, but M 129 reached low rates of photosynthesis (2 ,mol m,2 s,1) and transpiration at a WP of ,1.7 MPa, whereas Tyson reached the same low rate at ,2.4 MPa. While OA varied among the chickpea genotypes, the differences were not associated with the changes in carbohydrate composition or the rates of gas exchange at low values of WP. Further, the degree of OA of the 11 genotypes was not the same as when they were selected for differences in OA under rainout shelter conditions in the field in Australia, suggesting that OA may show poor stability depending upon the stress level, location or physiological stage of the plant. This suggests that OA is not a valuable drought-resistance trait to select for in chickpea breeding programmes. [source] A novel type of carbohydrate,protein linkage region in the tyrosine-bound S-layer glycan of Thermoanaerobacterium thermosaccharolyticum D120-70FEBS JOURNAL, Issue 17 2000Christina Schäffer The surface-layer (S-layer) protein of Thermoanaerobacterium thermosaccharolyticum D120-70 contains glycosidically linked glycan chains with the repeating unit structure ,4)[,- d -Galp -(1,2)]-,- l -Rhap -(1,3)[,- d -Glcp -(1,6)]-,- d -Manp -(1,4)-,- l -Rhap -(1,3)-,- d -Glcp -(1,. After proteolytic degradation of the S-layer glycoprotein, three glycopeptide pools were isolated, which were analyzed for their carbohydrate and amino-acid compositions. In all three pools, tyrosine was identified as the amino-acid constituent, and the carbohydrate compositions corresponded to the above structure. Native polysaccharide PAGE showed the specific heterogeneity of each pool. For examination of the carbohydrate,protein linkage region, the S-layer glycan chain was partially hydrolyzed with trifluoroacetic acid. 1D and 2D NMR spectroscopy, including a novel diffusion-edited difference experiment, showed the O-glycosidic linkage region ,- d -glucopyranose,O -tyrosine. No evidence was found of additional sugars originating from a putative core region between the glycan repeating units and the S-layer polypeptide. For the determination of chain-length variability in the S-layer glycan, the different glycopeptide pools were investigated by matrix-assisted laser desorption ionization-time of flight mass spectrometry, revealing that the degree of polymerization of the S-layer glycan repeats varied between three and 10. All masses were assigned to multiples of the repeating units plus the peptide portion. This result implies that no core structure is present and thus supports the data from the NMR spectroscopy analyses. This is the first observation of a bacterial S-layer glycan without a core region connecting the carbohydrate moiety with the polypeptide portion. [source] Novel elicitin-like proteins isolated from the cell wall of the biocontrol agent Pythium oligandrum induce defence-related genes in sugar beetMOLECULAR PLANT PATHOLOGY, Issue 5 2006SHIGEHITO TAKENAKA SUMMARY We previously reported that cell wall protein fractions (CWPs) of the biocontrol agent Pythium oligandrum have elicitor properties in sugar beet and wheat. Here we have examined the effect of treatment with the D -type of CWP, a fraction that contains two major forms (POD-1 and POD-2), on the induction of defence-related genes in sugar beet. Using PCR-based cDNA library subtraction, we identified five genes that were highly expressed in response to CWP treatment. The five genes are probably of oxalate oxidase-like germin (OxOLG), glutathione S-transferase (GST), 5-enol-pyruvylshikimate-phosphate synthase (EPSPS), phenylalanine ammonia-lyase (PAL) and aspartate aminotransferase (AAT). In addition, we purified and characterized POD-1 and POD-2 and found that POD-1 induced all five genes, whereas POD-2 induced three of the genes, but not OxOLG or GST. A sugar beet bioassay indicated that CWP, POD-1 and POD-2 are each sufficient to induce resistance to sugar beet seedling disease caused by Aphanomyces cochlioides. Although carbohydrate analyses indicated that POD proteins were glycoproteins with similar carbohydrate compositions, containing approximately 15.0% carbohydrate by weight, their peptide portions have elicitor activity. Furthermore, cDNAs of POD-1 and POD-2 proteins were cloned, and the deduced amino acid sequences were found to be 82.9% identical. Characterization of their molecular structures indicated that they have an elicitin domain followed by a C-terminal domain with a high frequency of Ser, Thr, Ala and Pro, which is structurally similar to class III elicitins. However, phylogenetic analysis with 22 representative elicitin and elicitin-like proteins showed that POD-1 and POD-2 are distinct from previously defined elicitin and elicitin-like proteins. Therefore, POD-1 and POD-2 are novel oomycete cell wall elicitin-like glycoproteins. [source] | ||||||||||||||||