Methodological challenges in carbohydrate analyses

Directory of Open Access Journals (Sweden)

Mary Beth Hall

2007-07-01

Full Text Available Carbohydrates can provide up to 80% of the dry matter in animal diets, yet their specific evaluation for research and diet formulation is only now becoming a focus in the animal sciences. Partitioning of dietary carbohydrates for nutritional purposes should reflect differences in digestion and fermentation characteristics and effects on animal performance. Key challenges to designating nutritionally important carbohydrate fractions include classifying the carbohydrates in terms of nutritional characteristics, and selecting analytical methods that describe the desired fraction. The relative lack of information on digestion characteristics of various carbohydrates and their interactions with other fractions in diets means that fractions will not soon be perfectly established. Developing a system of carbohydrate analysis that could be used across animal species could enhance the utility of analyses and amount of data we can obtain on dietary effects of carbohydrates. Based on quantities present in diets and apparent effects on animal performance, some nutritionally important classes of carbohydrates that may be valuable to measure include sugars, starch, fructans, insoluble fiber, and soluble fiber. Essential to selection of methods for these fractions is agreement on precisely what carbohydrates should be included in each. Each of these fractions has analyses that could potentially be used to measure them, but most of the available methods have weaknesses that must be evaluated to see if they are fatal and the assay is unusable, or if the assay still may be made workable. Factors we must consider as we seek to analyze carbohydrates to describe diets: Does the assay accurately measure the desired fraction? Is the assay for research, regulatory, or field use (affects considerations of acceptable costs and throughput? What are acceptable accuracy and variability of measures? Is the assay robust (enhances accuracy of values? For some carbohydrates, we

Cats and Carbohydrates: The Carnivore Fantasy?

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Adronie Verbrugghe

2017-11-01

Full Text Available The domestic cat’s wild ancestors are obligate carnivores that consume prey containing only minimal amounts of carbohydrates. Evolutionary events adapted the cat’s metabolism and physiology to this diet strictly composed of animal tissues and led to unique digestive and metabolic peculiarities of carbohydrate metabolism. The domestic cat still closely resembles its wild ancestor. Although the carnivore connection of domestic cats is well recognised, little is known about the precise nutrient profile to which the digestive physiology and metabolism of the cat have adapted throughout evolution. Moreover, studies show that domestic cats balance macronutrient intake by selecting low-carbohydrate foods. The fact that cats evolved consuming low-carbohydrate prey has led to speculations that high-carbohydrate diets could be detrimental for a cat’s health. More specifically, it has been suggested that excess carbohydrates could lead to feline obesity and diabetes mellitus. Additionally, the chances for remission of diabetes mellitus are higher in cats that consume a low-carbohydrate diet. This literature review will summarise current carbohydrate knowledge pertaining to digestion, absorption and metabolism of carbohydrates, food selection and macronutrient balancing in healthy, obese and diabetic cats, as well as the role of carbohydrates in prevention and treatment of obesity and diabetes mellitus.

A systematic study of chemogenomics of carbohydrates.

Science.gov (United States)

Gu, Jiangyong; Luo, Fang; Chen, Lirong; Yuan, Gu; Xu, Xiaojie

2014-03-04

Chemogenomics focuses on the interactions between biologically active molecules and protein targets for drug discovery. Carbohydrates are the most abundant compounds in natural products. Compared with other drugs, the carbohydrate drugs show weaker side effects. Searching for multi-target carbohydrate drugs can be regarded as a solution to improve therapeutic efficacy and safety. In this work, we collected 60 344 carbohydrates from the Universal Natural Products Database (UNPD) and explored the chemical space of carbohydrates by principal component analysis. We found that there is a large quantity of potential lead compounds among carbohydrates. Then we explored the potential of carbohydrates in drug discovery by using a network-based multi-target computational approach. All carbohydrates were docked to 2389 target proteins. The most potential carbohydrates for drug discovery and their indications were predicted based on a docking score-weighted prediction model. We also explored the interactions between carbohydrates and target proteins to find the pathological networks, potential drug candidates and new indications.

Phenol-Sulfuric Acid Method for Total Carbohydrates

Science.gov (United States)

Nielsen, S. Suzanne

The phenol-sulfuric acid method is a simple and rapid colorimetric method to determine total carbohydrates in a sample. The method detects virtually all classes of carbohydrates, including mono-, di-, oligo-, and polysaccharides. Although the method detects almost all carbohydrates, the absorptivity of the different carbohydrates varies. Thus, unless a sample is known to contain only one carbohydrate, the results must be expressed arbitrarily in terms of one carbohydrate.

Complexes of natural carbohydrates with metal cations

International Nuclear Information System (INIS)

Alekseev, Yurii E; Garnovskii, Alexander D; Zhdanov, Yu A

1998-01-01

Data on the interaction of natural carbohydrates (mono-, oligo-, and poly-saccharides, amino sugars, and natural organic acids of carbohydrate origin) with metal cations are surveyed and described systematically. The structural diversity of carbohydrate metal complexes, caused by some specific features of carbohydrates as ligands, is demonstrated. The influence of complex formation on the chemical properties of carbohydrates is discussed. It is shown that the formation of metal complexes plays an important role in the configurational and conformational analysis of carbohydrates. The practical significance of the coordination interaction in the series of carbohydrate ligands is demonstrated. The bibliography includes 571 references.

Renewable Hydrogen Carrier — Carbohydrate: Constructing the Carbon-Neutral Carbohydrate Economy

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Y.-H. Percival Zhang

2011-01-01

Full Text Available The hydrogen economy presents an appealing energy future but its implementation must solve numerous problems ranging from low-cost sustainable production, high-density storage, costly infrastructure, to eliminating safety concern. The use of renewable carbohydrate as a high-density hydrogen carrier and energy source for hydrogen production is possible due to emerging cell-free synthetic biology technology—cell-free synthetic pathway biotransformation (SyPaB. Assembly of numerous enzymes and co-enzymes in vitro can create complicated set of biological reactions or pathways that microorganisms or catalysts cannot complete, for example, C6H10O5 (aq + 7 H2O (l à 12 H2 (g + 6 CO2 (g (PLoS One 2007, 2:e456. Thanks to 100% selectivity of enzymes, modest reaction conditions, and high-purity of generated hydrogen, carbohydrate is a promising hydrogen carrier for end users. Gravimetric density of carbohydrate is 14.8 H2 mass% if water can be recycled from proton exchange membrane fuel cells or 8.33% H2 mass% without water recycling. Renewable carbohydrate can be isolated from plant biomass or would be produced from a combination of solar electricity/hydrogen and carbon dioxide fixation mediated by high-efficiency artificial photosynthesis mediated by SyPaB. The construction of this carbon-neutral carbohydrate economy would address numerous sustainability challenges, such as electricity and hydrogen storage, CO2 fixation and long-term storage, water conservation, transportation fuel production, plus feed and food production.

Renewable Hydrogen Carrier - Carbohydrate: Constructing the Carbon-Neutral Carbohydrate Economy

Science.gov (United States)

2011-01-31

combinations have been investigated for the production of hydrogen from biomass carbohydrate. Chemical catalysis approaches include pyrolysis [19...temperature. High fructose corn syrup, low-cost sucrose replacement, is made by stabilized glucose isomerase, which can work at ~60 °C for even about two...gasoline, vegetable oil vs. biodiesel, corn kernels vs. ethanol [31,109]. Given a price of $0.18/kg carbohydrate (i.e., $10.6/GJ) [2,44], the hydrogen

Using Carbohydrate Interaction Assays to Reveal Novel Binding Sites in Carbohydrate Active Enzymes

DEFF Research Database (Denmark)

Cockburn, Darrell; Wilkens, Casper; Dilokpimol, Adiphol

2016-01-01

Carbohydrate active enzymes often contain auxiliary binding sites located either on independent domains termed carbohydrate binding modules (CBMs) or as so-called surface binding sites (SBSs) on the catalytic module at a certain distance from the active site. The SBSs are usually critical...

Carbohydrates Through Animation: Preliminary Step

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J.K. Sugai

2004-05-01

Full Text Available Methods of education are changing, so the educational tools must change too. The developmentof the systems of information and communication gave the opportunity to bring new technology tothe learning process. Modern education needs interactive programs that may be available to theacademic community, in order to ease the learning process and sharing of the knowledge. Then,an educational software on Carbohydrates is being developed using concept maps and FLASH-MXanimations program, and approached through six modules. The introduction of Carbohydrates wasmade by the module Carbohydrates on Nature, which shows the animations gures of a teacher andstudents, visiting a farm, identifying the carbohydrates found in vegetables, animals, and microor-ganisms, integrated by links containing short texts to help understanding the structure and functionof carbohydrates. This module was presented, as pilot experiment, to teachers and students, whichdemonstrated satisfaction, and high receptivity, by using animation and interactivitys program asstrategy to biochemistrys education. The present work is part of the project Biochemistry throughanimation, which is having continuity.

Predicting water-soluble carbohydrates and ethanol-soluble carbohydrates in cool-season grasses with near-infrared reflectance spectroscopy

Science.gov (United States)

Grazing animals may require a high or low total nonstructural carbohydrate diet for optimal health and production. Understanding how nonstructural carbohydrates fluctuate in Kentucky pastures and being able to quantify and monitor nonstructural carbohydrates in a timely manner will greatly aid in m...

Discovery and design of carbohydrate-based therapeutics.

Science.gov (United States)

Cipolla, Laura; Araújo, Ana C; Bini, Davide; Gabrielli, Luca; Russo, Laura; Shaikh, Nasrin

2010-08-01

Till now, the importance of carbohydrates has been underscored, if compared with the two other major classes of biopolymers such as oligonucleotides and proteins. Recent advances in glycobiology and glycochemistry have imparted a strong interest in the study of this enormous family of biomolecules. Carbohydrates have been shown to be implicated in recognition processes, such as cell-cell adhesion, cell-extracellular matrix adhesion and cell-intruder recognition phenomena. In addition, carbohydrates are recognized as differentiation markers and as antigenic determinants. Due to their relevant biological role, carbohydrates are promising candidates for drug design and disease treatment. However, the growing number of human disorders known as congenital disorders of glycosylation that are being identified as resulting from abnormalities in glycan structures and protein glycosylation strongly indicates that a fast development of glycobiology, glycochemistry and glycomedicine is highly desirable. The topics give an overview of different approaches that have been used to date for the design of carbohydrate-based therapeutics; this includes the use of native synthetic carbohydrates, the use of carbohydrate mimics designed on the basis of their native counterpart, the use of carbohydrates as scaffolds and finally the design of glyco-fused therapeutics, one of the most recent approaches. The review covers mainly literature that has appeared since 2000, except for a few papers cited for historical reasons. The reader will gain an overview of the current strategies applied to the design of carbohydrate-based therapeutics; in particular, the advantages/disadvantages of different approaches are highlighted. The topic is presented in a general, basic manner and will hopefully be a useful resource for all readers who are not familiar with it. In addition, in order to stress the potentialities of carbohydrates, several examples of carbohydrate-based marketed therapeutics are given

Carbohydrates of human immunodeficiency virus

DEFF Research Database (Denmark)

Hansen, J E

1992-01-01

Elucidation of the mechanism by which viral infection induces the appearance of carbohydrate neoantigens is highly important. Results from such studies could be expected to be significant for a general understanding of the regulation of glycosylation, and perhaps especially important for the unde......Elucidation of the mechanism by which viral infection induces the appearance of carbohydrate neoantigens is highly important. Results from such studies could be expected to be significant for a general understanding of the regulation of glycosylation, and perhaps especially important...... therapy with glycosylation enzyme inhibitors will, however, require the development of more specific and less toxic compounds. If carbohydrate antigens can elicit a neutralizing immune response in vivo, the possibility exists that carbohydrate neoantigens can be utilized in the construction of a vaccine...

Carbohydrates digestion and metabolism in the spiny lobster (Panulirus argus): biochemical indication for limited carbohydrate utilization.

Science.gov (United States)

Rodríguez-Viera, Leandro; Perera, Erick; Montero-Alejo, Vivian; Perdomo-Morales, Rolando; García-Galano, Tsai; Martínez-Rodríguez, Gonzalo; Mancera, Juan M

2017-01-01

As other spiny lobsters, Panulirus argus is supposed to use preferentially proteins and lipids in energy metabolism, while carbohydrates are well digested but poorly utilized. The aim of this study was to evaluate the effect of dietary carbohydrate level on digestion and metabolism in the spiny lobster P. argus . We used complementary methodologies such as post-feeding flux of nutrients and metabolites, as well as measurements of α-amylase expression and activity in the digestive tract. Lobsters readily digested and absorbed carbohydrates with a time-course that is dependent on their content in diet. Lobster showed higher levels of free glucose and stored glycogen in different tissues as the inclusion of wheat flour increased. Modifications in intermediary metabolism revealed a decrease in amino acids catabolism coupled with a higher use of free glucose as carbohydrates rise up to 20%. However, this effect seems to be limited by the metabolic capacity of lobsters to use more than 20% of carbohydrates in diets. Lobsters were not able to tightly regulate α-amylase expression according to dietary carbohydrate level but exhibited a marked difference in secretion of this enzyme into the gut. Results are discussed to highlight the limitations to increasing carbohydrate utilization by lobsters. Further growout trials are needed to link the presented metabolic profiles with phenotypic outcomes.

Carbohydrates digestion and metabolism in the spiny lobster (Panulirus argus: biochemical indication for limited carbohydrate utilization

Directory of Open Access Journals (Sweden)

Leandro Rodríguez-Viera

2017-11-01

Full Text Available As other spiny lobsters, Panulirus argus is supposed to use preferentially proteins and lipids in energy metabolism, while carbohydrates are well digested but poorly utilized. The aim of this study was to evaluate the effect of dietary carbohydrate level on digestion and metabolism in the spiny lobster P. argus. We used complementary methodologies such as post-feeding flux of nutrients and metabolites, as well as measurements of α-amylase expression and activity in the digestive tract. Lobsters readily digested and absorbed carbohydrates with a time-course that is dependent on their content in diet. Lobster showed higher levels of free glucose and stored glycogen in different tissues as the inclusion of wheat flour increased. Modifications in intermediary metabolism revealed a decrease in amino acids catabolism coupled with a higher use of free glucose as carbohydrates rise up to 20%. However, this effect seems to be limited by the metabolic capacity of lobsters to use more than 20% of carbohydrates in diets. Lobsters were not able to tightly regulate α-amylase expression according to dietary carbohydrate level but exhibited a marked difference in secretion of this enzyme into the gut. Results are discussed to highlight the limitations to increasing carbohydrate utilization by lobsters. Further growout trials are needed to link the presented metabolic profiles with phenotypic outcomes.

Who is the carbohydrate?

Directory of Open Access Journals (Sweden)

Paulo Enrique Cuevas Mestanza

2017-10-01

Full Text Available Biochemistry is a complex science that studies biomolecules and their interactions in metabolic pathways in living beings. Due to the large amount of contents against the short period to apply them, only expositive classes are not enough to arouse the interest of students and solve questions. In this perspective, is very important to develop new educational tools to improve the understanding of these contents. “Who is the carbohydrate?” It is a didactic game created to review the structural and functional relationship of carbohydrates. Based on the classic “Guess who?” The objective of the player or group is to first find out the opponent's carbohydrate name.

Minimally refined biomass fuel. [carbohydrate-water-alcohol mixture

Energy Technology Data Exchange (ETDEWEB)

Pearson, R.K.; Hirschfeld, T.B.

1981-03-26

A minimally refined fluid composition, suitable as a fuel mixture and derived from biomass material, is comprised of one or more water-soluble carbohydrates such as sucrose, one or more alcohols having less than four carbons, and water. The carbohydrate provides the fuel source; water-solubilizes the carbohydrate; and the alcohol aids in the combustion of the carbohydrate and reduces the viscosity of the carbohydrate/water solution. Because less energy is required to obtain the carbohydrate from the raw biomass than alcohol, an overall energy savings is realized compared to fuels employing alcohol as the primary fuel.

Technological aspects of functional food-related carbohydrates.

NARCIS (Netherlands)

Voragen, A.G.J.

1998-01-01

Carbohydrates in food occur as natural constituents or are added as ingredients or additives. The most important endogenous carbohydrates in food are starch, depolymerized starch, sucrose, lactose, glucose, fructose and sorbitol (digestible) and carbohydrates such as raffinose, stachyose, resistant

Metabolic aspects of low carbohydrate diets and exercise

Directory of Open Access Journals (Sweden)

Peters Sandra

2004-01-01

Full Text Available Abstract Following a low carbohydrate diet, there is a shift towards more fat and less carbohydrate oxidation to provide energy to skeletal muscle, both at rest and during exercise. This review summarizes recent work on human skeletal muscle carbohydrate and fat metabolic adaptations to a low carbohydrate diet, focusing mainly on pyruvate dehydrogenase and pyruvate dehydrogenase kinase, and how these changes relate to the capacity for carbohydrate oxidation during exercise.

Randomized controlled trial of changes in dietary carbohydrate/fat ratio and simple vs complex carbohydrates on body weight and blood lipids: the CARMEN study. The Carbohydrate Ratio Management in European National diets.

Science.gov (United States)

Saris, W H; Astrup, A; Prentice, A M; Zunft, H J; Formiguera, X; Verboeket-van de Venne, W P; Raben, A; Poppitt, S D; Seppelt, B; Johnston, S; Vasilaras, T H; Keogh, G F

2000-10-01

To investigate the long-term effects of changes in dietary carbohydrate/fat ratio and simple vs complex carbohydrates. Randomized controlled multicentre trial (CARMEN), in which subjects were allocated for 6 months either to a seasonal control group (no intervention) or to one of three experimental groups: a control diet group (dietary intervention typical of the average national intake); a low-fat high simple carbohydrate group; or a low-fat high complex carbohydrate group. Three hundred and ninety eight moderately obese adults. The change in body weight was the primary outcome; changes in body composition and blood lipids were secondary outcomes. Body weight loss in the low-fat high simple carbohydrate and low-fat high complex carbohydrate groups was 0.9 kg (P Fat mass changed by -1.3kg (Plow-fat high simple carbohydrate, low-fat high complex carbohydrate and control diet groups, respectively. Changes in blood lipids did not differ significantly between the dietary treatment groups. Our findings suggest that reduction of fat intake results in a modest but significant reduction in body weight and body fatness. The concomitant increase in either simple or complex carbohydrates did not indicate significant differences in weight change. No adverse effects on blood lipids were observed. These findings underline the importance of this dietary change and its potential impact on the public health implications of obesity.

Vacuum ultraviolet photoionization of carbohydrates and nucleotides

Energy Technology Data Exchange (ETDEWEB)

Shin, Joong-Won, E-mail: jshin@govst.edu [Division of Science, Governors State University, University Park, Illinois 60484-0975 (United States); Department of Chemistry, Colorado State University, Fort Collins, Colorado 80523-1872 (United States); Bernstein, Elliot R., E-mail: erb@lamar.colostate.edu [Department of Chemistry, Colorado State University, Fort Collins, Colorado 80523-1872 (United States)

2014-01-28

Carbohydrates (2-deoxyribose, ribose, and xylose) and nucleotides (adenosine-, cytidine-, guanosine-, and uridine-5{sup ′}-monophosphate) are generated in the gas phase, and ionized with vacuum ultraviolet photons (VUV, 118.2 nm). The observed time of flight mass spectra of the carbohydrate fragmentation are similar to those observed [J.-W. Shin, F. Dong, M. Grisham, J. J. Rocca, and E. R. Bernstein, Chem. Phys. Lett. 506, 161 (2011)] for 46.9 nm photon ionization, but with more intensity in higher mass fragment ions. The tendency of carbohydrate ions to fragment extensively following ionization seemingly suggests that nucleic acids might undergo radiation damage as a result of carbohydrate, rather than nucleobase fragmentation. VUV photoionization of nucleotides (monophosphate-carbohydrate-nucleobase), however, shows that the carbohydrate-nucleobase bond is the primary fragmentation site for these species. Density functional theory (DFT) calculations indicate that the removed carbohydrate electrons by the 118.2 nm photons are associated with endocyclic C–C and C–O ring centered orbitals: loss of electron density in the ring bonds of the nascent ion can thus account for the observed fragmentation patterns following carbohydrate ionization. DFT calculations also indicate that electrons removed from nucleotides under these same conditions are associated with orbitals involved with the nucleobase-saccharide linkage electron density. The calculations give a general mechanism and explanation of the experimental results.

Vacuum ultraviolet photoionization of carbohydrates and nucleotides

International Nuclear Information System (INIS)

Shin, Joong-Won; Bernstein, Elliot R.

2014-01-01

Carbohydrates (2-deoxyribose, ribose, and xylose) and nucleotides (adenosine-, cytidine-, guanosine-, and uridine-5 ′ -monophosphate) are generated in the gas phase, and ionized with vacuum ultraviolet photons (VUV, 118.2 nm). The observed time of flight mass spectra of the carbohydrate fragmentation are similar to those observed [J.-W. Shin, F. Dong, M. Grisham, J. J. Rocca, and E. R. Bernstein, Chem. Phys. Lett. 506, 161 (2011)] for 46.9 nm photon ionization, but with more intensity in higher mass fragment ions. The tendency of carbohydrate ions to fragment extensively following ionization seemingly suggests that nucleic acids might undergo radiation damage as a result of carbohydrate, rather than nucleobase fragmentation. VUV photoionization of nucleotides (monophosphate-carbohydrate-nucleobase), however, shows that the carbohydrate-nucleobase bond is the primary fragmentation site for these species. Density functional theory (DFT) calculations indicate that the removed carbohydrate electrons by the 118.2 nm photons are associated with endocyclic C–C and C–O ring centered orbitals: loss of electron density in the ring bonds of the nascent ion can thus account for the observed fragmentation patterns following carbohydrate ionization. DFT calculations also indicate that electrons removed from nucleotides under these same conditions are associated with orbitals involved with the nucleobase-saccharide linkage electron density. The calculations give a general mechanism and explanation of the experimental results

Cell surface carbohydrates as prognostic markers in human carcinomas

DEFF Research Database (Denmark)

Dabelsteen, Erik

1996-01-01

Tumour development is usually associated with changes in cell surface carbohydrates. These are often divided into changes related to terminal carbohydrate structures, which include incomplete synthesis and modification of normally existing carbohydrates, and changes in the carbohydrate core...... structure. The latter includes chain elongation of both glycolipids and proteins, increased branching of carbohydrates in N-linked glycoproteins, and blocked synthesis of carbohydrates in O-linked mucin-like glycoproteins. In mature organisms, expression of distinct carbohydrates is restricted to specific...... cell types; within a given tissue, variation in expression may be related to cell maturation. Tumour-associated carbohydrate structures often reflect a certain stage of cellular development; most of these moieties are structures normally found in other adult or embryonic tissues. There is no unique...

Dietary carbohydrates and glucose metabolism in diabetic patients.

Science.gov (United States)

Parillo, M; Riccardi, G

1995-12-01

Dietary carbohydrates represent one of the major sources of energy for the human body. However, the main (if not the only) therapy for diabetes since ancient times has been based on reducing dietary carbohydrates drastically because of their effects on blood glucose levels. The introduction of insulin in the 1920s and then of oral hypoglycaemic drugs led to various studies evaluating the biochemical characteristics of carbohydrates and their effects on glucose metabolism in diabetic patients. This review considers the role of dietary carbohydrates in the diet of diabetic patients in the light of the most recent studies and provides a short summary of the biochemistry of carbohydrates and the physiology of carbohydrate digestion.

Assessing Bacterial Interactions Using Carbohydrate-Based Microarrays

Directory of Open Access Journals (Sweden)

Andrea Flannery

2015-12-01

Full Text Available Carbohydrates play a crucial role in host-microorganism interactions and many host glycoconjugates are receptors or co-receptors for microbial binding. Host glycosylation varies with species and location in the body, and this contributes to species specificity and tropism of commensal and pathogenic bacteria. Additionally, bacterial glycosylation is often the first bacterial molecular species encountered and responded to by the host system. Accordingly, characterising and identifying the exact structures involved in these critical interactions is an important priority in deciphering microbial pathogenesis. Carbohydrate-based microarray platforms have been an underused tool for screening bacterial interactions with specific carbohydrate structures, but they are growing in popularity in recent years. In this review, we discuss carbohydrate-based microarrays that have been profiled with whole bacteria, recombinantly expressed adhesins or serum antibodies. Three main types of carbohydrate-based microarray platform are considered; (i conventional carbohydrate or glycan microarrays; (ii whole mucin microarrays; and (iii microarrays constructed from bacterial polysaccharides or their components. Determining the nature of the interactions between bacteria and host can help clarify the molecular mechanisms of carbohydrate-mediated interactions in microbial pathogenesis, infectious disease and host immune response and may lead to new strategies to boost therapeutic treatments.

Analysis and validation of carbohydrate three-dimensional structures

International Nuclear Information System (INIS)

Lütteke, Thomas

2009-01-01

The article summarizes the information that is gained from and the errors that are found in carbohydrate structures in the Protein Data Bank. Validation tools that can locate these errors are described. Knowledge of the three-dimensional structures of the carbohydrate molecules is indispensable for a full understanding of the molecular processes in which carbohydrates are involved, such as protein glycosylation or protein–carbohydrate interactions. The Protein Data Bank (PDB) is a valuable resource for three-dimensional structural information on glycoproteins and protein–carbohydrate complexes. Unfortunately, many carbohydrate moieties in the PDB contain inconsistencies or errors. This article gives an overview of the information that can be obtained from individual PDB entries and from statistical analyses of sets of three-dimensional structures, of typical problems that arise during the analysis of carbohydrate three-dimensional structures and of the validation tools that are currently available to scientists to evaluate the quality of these structures

Aminooxylated Carbohydrates: Synthesis and Applications.

Science.gov (United States)

Pifferi, Carlo; Daskhan, Gour Chand; Fiore, Michele; Shiao, Tze Chieh; Roy, René; Renaudet, Olivier

2017-08-09

Among other classes of biomolecules, carbohydrates and glycoconjugates are widely involved in numerous biological functions. In addition to addressing the related synthetic challenges, glycochemists have invested intense efforts in providing access to structures that can be used to study, activate, or inhibit these biological processes. Over the past few decades, aminooxylated carbohydrates have been found to be key building blocks for achieving these goals. This review provides the first in-depth overview covering several aspects related to the syntheses and applications of aminooxylated carbohydrates. After a brief introduction to oxime bonds and their relative stabilities compared to related C═N functions, synthetic aspects of oxime ligation and methodologies for introducing the aminooxy functionality onto both glycofuranosyls and glycopyranosyls are described. The subsequent section focuses on biological applications involving aminooxylated carbohydrates as components for the construcion of diverse architectures. Mimetics of natural structures represent useful tools for better understanding the features that drive carbohydrate-receptor interaction, their biological output and they also represent interesting structures with improved stability and tunable properties. In the next section, multivalent structures such as glycoclusters and glycodendrimers obtained through oxime ligation are described in terms of synthetic design and their biological applications such as immunomodulators. The second-to-last section discusses miscellaneous applications of oxime-based glycoconjugates, such as enantioselective catalysis and glycosylated oligonucleotides, and conclusions and perspectives are provided in the last section.

A Universal Protocol for Photochemical Covalent Immobilization of Intact Carbohydrates for the Preparation of Carbohydrate Microarrays

Science.gov (United States)

Wang, Huibin; Zhang, Yiming; Yuan, Xun; Chen, Yi; Yan, Mingdi

2010-01-01

A universal photochemical method has been established for the immobilization of intact carbohydrates and their analogues, and for the fabrication of carbohydrate microarrays. The method features the use of perfluorophenyl azide (PFPA)-modified substrates and the photochemical reaction of surface azido groups with printed carbohydrates. Various aldoses, ketoses, non-reducing sugars such as alditols and their derivatives can be directly arrayed on the PFPA-modified chips. The lectin-recognition ability of arrayed mannose, glucose and their oligo- and polysaccharides were confirmed using surface plasmon resonance imaging and laser-induced fluorescence imaging. PMID:21138274

Qualitative Carbohydrate Analysis using Alkaline Potassium ...

Indian Academy of Sciences (India)

IAS Admin

CLASSROOM. 285. RESONANCE | March 2016. Qualitative Carbohydrate Analysis using Alkaline. Potassium Ferricyanide. Keywords. Alkaline potassium ferricyanide, qualitative ... Carbohydrates form a distinct class of organic compounds often .... Laboratory Techniques: A contemporary Approach, W B Saunders Com-.

Utilization of carbohydrates by radiation processing

International Nuclear Information System (INIS)

Kume, T.; Nagasawa, N.; Yoshii, F.

2002-01-01

Upgrading and utilization of carbohydrates such as chitosan, sodium alginate, carrageenan, cellulose, pectin have been investigated for recycling these bio-resources and reducing the environmental pollution. These carbohydrates were easily degraded by irradiation and various kinds of biological activities such as anti-microbial activity, promotion of plant growth, suppression of heavy metal stress, phytoalexins induction, etc. were induced. On the other hand, some carbohydrate derivatives, carboxymethylcellulose and carboxymethylstarch, could be crosslinked under certain radiation condition and produce the biodegradable hydrogel for medical and agricultural use

Renal function following long-term weight loss in individuals with abdominal obesity on a very-low-carbohydrate diet vs high-carbohydrate diet.

Science.gov (United States)

Brinkworth, Grant D; Buckley, Jonathan D; Noakes, Manny; Clifton, Peter M

2010-04-01

A frequently cited concern of very-low-carbohydrate diets is the potential for increased risk of renal disease associated with a higher protein intake. However, to date, no well-controlled randomized studies have evaluated the long-term effects of very-low-carbohydrate diets on renal function. To study this issue, renal function was assessed in 68 men and women with abdominal obesity (age 51.5+/-7.7 years, body mass index [calculated as kg/m(2)] 33.6+/-4.0) without preexisting renal dysfunction who were randomized to consume either an energy-restricted ( approximately 1,433 to 1,672 kcal/day), planned isocaloric very-low-carbohydrate (4% total energy as carbohydrate [14 g], 35% protein [124 g], 61% fat [99 g]), or high-carbohydrate diet (46% total energy as carbohydrate [162 g], 24% protein [85 g], 30% fat [49 g]) for 1 year. Body weight, serum creatinine, estimated glomerular filtration rate and urinary albumin excretion were assessed before and after 1 year (April 2006-July 2007). Repeated measures analysis of variance was conducted. Weight loss was similar in both groups (very-low-carbohydrate: -14.5+/-9.7 kg, high-carbohydrate: -11.6+/-7.3 kg; P=0.16). By 1 year, there were no changes in either group in serum creatinine levels (very-low-carbohydrate: 72.4+/-15.1 to 71.3+/-13.8 mumol/L, high-carbohydrate: 78.0+/-16.0 to 77.2+/-13.2 mumol/L; P=0.93 time x diet effect) or estimated glomerular filtration rate (very-low-carbohydrate: 90.0+/-17.0 to 91.2+/-17.8 mL/min/1.73 m(2), high-carbohydrate: 83.8+/-13.8 to 83.6+/-11.8 mL/min/1.73 m(2); P=0.53 time x diet effect). All but one participant was classified as having normoalbuminuria at baseline, and for these participants, urinary albumin excretion values remained in the normoalbuminuria range at 1 year. One participant in high-carbohydrate had microalbuminuria (41.8 microg/min) at baseline, which decreased to a value of 3.1 microg/min (classified as normoalbuminuria) at 1 year. This study provides preliminary

Carbohydrate Nutrition and Team Sport Performance.

Science.gov (United States)

Williams, Clyde; Rollo, Ian

2015-11-01

The common pattern of play in 'team sports' is 'stop and go', i.e. where players perform repeated bouts of brief high-intensity exercise punctuated by lower intensity activity. Sprints are generally 2-4 s long and recovery between sprints is of variable length. Energy production during brief sprints is derived from the degradation of intra-muscular phosphocreatine and glycogen (anaerobic metabolism). Prolonged periods of multiple sprints drain muscle glycogen stores, leading to a decrease in power output and a reduction in general work rate during training and competition. The impact of dietary carbohydrate interventions on team sport performance have been typically assessed using intermittent variable-speed shuttle running over a distance of 20 m. This method has evolved to include specific work to rest ratios and skills specific to team sports such as soccer, rugby and basketball. Increasing liver and muscle carbohydrate stores before sports helps delay the onset of fatigue during prolonged intermittent variable-speed running. Carbohydrate intake during exercise, typically ingested as carbohydrate-electrolyte solutions, is also associated with improved performance. The mechanisms responsible are likely to be the availability of carbohydrate as a substrate for central and peripheral functions. Variable-speed running in hot environments is limited by the degree of hyperthermia before muscle glycogen availability becomes a significant contributor to the onset of fatigue. Finally, ingesting carbohydrate immediately after training and competition will rapidly recover liver and muscle glycogen stores.

Carbohydrate malabsorption

DEFF Research Database (Denmark)

Rumessen, J J; Nordgaard-Andersen, I; Gudmand-Høyer, E

1994-01-01

Previous studies in small series of healthy adults have suggested that parallel measurement of hydrogen and methane resulting from gut fermentation may improve the precision of quantitative estimates of carbohydrate malabsorption. Systematic, controlled studies of the role of simultaneous hydrogen...

Differential carbohydrate media and anaerobic replica plating techniques in delineating carbohydrate-utilizing subgroups in rumen bacterial populations.

OpenAIRE

Leedle, J A; Hespell, R B

1980-01-01

A basal (BC) medium devoid of added carbohydrates, a complete (CC) medium containing nine carbohydrates were developed for enumerating rumen bacteria. The colony counts on the BC medium were 85 to 100% of those obtained on the CC medium. These colonies were pinpoint size (less than or equal to mm in diameter) but increased in size (2 to 5 mm in diameter) when carbohydrates were subsequently added. With the CC medium or other media tested, the colony counts were 20 to 50% higher on plates than...

Perceived hunger is lower and weight loss is greater in overweight premenopausal women consuming a low-carbohydrate/high-protein vs high-carbohydrate/low-fat diet.

Science.gov (United States)

Nickols-Richardson, Sharon M; Coleman, Mary Dean; Volpe, Joanne J; Hosig, Kathy W

2005-09-01

The impact of a low-carbohydrate/high-protein diet compared with a high-carbohydrate/low-fat diet on ratings of hunger and cognitive eating restraint were examined. Overweight premenopausal women consumed a low-carbohydrate/high-protein (n=13) or high-carbohydrate/low-fat diet (n=15) for 6 weeks. Fasting body weight (BW) was measured and the Eating Inventory was completed at baseline, weeks 1 to 4, and week 6. All women experienced a reduction in BW (Plow-carbohydrate/high-protein vs high-carbohydrate/low-fat group at week 6 (Plow-carbohydrate/high-protein but not in the high-carbohydrate/low-fat group from baseline to week 6. In both groups, self-rated cognitive eating restraint increased (Plow-carbohydrate/high-protein group may have contributed to a greater percentage of BW loss.

Carbohydrate clearance receptors in transfusion medicine

DEFF Research Database (Denmark)

Sørensen, Anne Louise Tølbøll; Clausen, Henrik; Wandall, Hans H

2012-01-01

Complex carbohydrates play important functions for circulation of proteins and cells. They provide protective shields and refraction from non-specific interactions with negative charges from sialic acids to enhance circulatory half-life. For recombinant protein therapeutics carbohydrates are espe...

Effect of Carbohydrate, Caffeine, and Carbohydrate + Caffeine Mouth Rinsing on Intermittent Running Performance in Collegiate Male Lacrosse Athletes.

Science.gov (United States)

Dolan, Patrick; Witherbee, Kyle E; Peterson, Kimi M; Kerksick, Chad M

2017-09-01

Dolan, P, Witherbee, KE, Peterson, KM, and Kerksick, CM. Effect of carbohydrate, caffeine, and carbohydrate + caffeine mouth rinsing on intermittent running performance in collegiate male lacrosse athletes. J Strength Cond Res 31(9): 2473-2479, 2017-Recently, an interest has developed in the potential to rinse the oral cavity with key nutrients to impact various types of exercise and presumably sporting performance. Although multiple studies examining carbohydrate mouth rinsing have been completed, conflicting evidence surrounding caffeine mouth rinsing persists, and no research has explored its ability to impact high-intensity, intermittent running performance. This study investigated the independent and synergistic ability of carbohydrate and caffeine mouth rinsing to improve intermittent running performance. The Yo-Yo Intermittent Recovery Test-Level 1 (Yo-Yo Level 1) was completed in 10 collegiate (National Collegiate Athletic Association [NCAA] Division II) male lacrosse players after a 10-second mouth rinse with a solution of either carbohydrate (CHO), caffeine (CAF), carbohydrate + caffeine (CHO + CAF), placebo (H2O), or a no rinse control (CON). No significant improvements in Yo-Yo IRT-1 performance were found (p > 0.05). Perceptual indications of effort (i.e., rating of their perceived exertion [RPE]) were significantly lower (p ≤ 0.05) in CHO and CHO + CAF when compared with CON after speed level 11. Interestingly, RPE levels were nonsignificantly lower in all but one level of the Yo-Yo Level 1 for CHO in comparison with other groups. Carbohydrate and caffeine mouth rinsing seems to exert no impact on running performance before maximal intermittent running in a group of male collegiate lacrosse players.

Optical absorption of irradiated carbohydrates

International Nuclear Information System (INIS)

Supe, A.A.; Tiliks, Yu.E.

1994-01-01

The optical absorption spectra of γ-irradiated carbohydrates (glucose, lactose, sucrose, maltose, and starch) and their aqueous solutions were studied. The comparison of the data obtained with the determination of the concentrations of molecular and radical products of radiolysis allows the absorption bands with maxima at 250 and 310 nm to be assigned to the radicals trapped in the irradiated carbohydrates

Linking Bacillus cereus Genotypes and Carbohydrate Utilization Capacity.

Directory of Open Access Journals (Sweden)

Alicja K Warda

Full Text Available We characterised carbohydrate utilisation of 20 newly sequenced Bacillus cereus strains isolated from food products and food processing environments and two laboratory strains, B. cereus ATCC 10987 and B. cereus ATCC 14579. Subsequently, genome sequences of these strains were analysed together with 11 additional B. cereus reference genomes to provide an overview of the different types of carbohydrate transporters and utilization systems found in B. cereus strains. The combined application of API tests, defined growth media experiments and comparative genomics enabled us to link the carbohydrate utilisation capacity of 22 B. cereus strains with their genome content and in some cases to the panC phylogenetic grouping. A core set of carbohydrates including glucose, fructose, maltose, trehalose, N-acetyl-glucosamine, and ribose could be used by all strains, whereas utilisation of other carbohydrates like xylose, galactose, and lactose, and typical host-derived carbohydrates such as fucose, mannose, N-acetyl-galactosamine and inositol is limited to a subset of strains. Finally, the roles of selected carbohydrate transporters and utilisation systems in specific niches such as soil, foods and the human host are discussed.

Wood adhesives containing proteins and carbohydrates

Science.gov (United States)

In recent years there has been resurgent interest in using biopolymers as sustainable and environmentally friendly ingredients in wood adhesive formulations. Among them, proteins and carbohydrates are the most commonly used. In this chapter, an overview is given of protein-based and carbohydrate-...

Carbohydrate epitopes on Haemonchus contortus antigens

NARCIS (Netherlands)

Schallig, H. D.; van Leeuwen, M. A.

1996-01-01

Extracts of infective larvae and adults of the trichostrongylid Haemonchus contortus were studied for the presence of carbohydrate moieties. Several different lectin-binding sites were demonstrated in both stages using a panel of nine lectins. The carbohydrate specificity of the lectins used

Association of carbohydrate and fat intake with metabolic syndrome.

Science.gov (United States)

Kwon, Yu-Jin; Lee, Hye-Sun; Lee, Ji-Won

2018-04-01

In Asia, dietary pattern has been changed with increased intake of refined carbohydrates, sugar, and saturated fat, while the prevalence of metabolic syndrome (MetS) is on the rise. However, it remains unclear whether a high-carbohydrate or a high-fat diet is more metabolically harmful, and the optimal amount of carbohydrates and fat has not been determined. The aim of our study was to examine the role of carbohydrate and fat intake in MetS in a Korean population. Data were obtained from a large, population-based, cross-sectional study (6737 males and 8845 females). The subjects were divided into nine groups based on carbohydrate and fat proportion, and multiple logistic regression analysis was performed after adjusting for confounding variables. Regardless of fat intake, the risk of MetS significantly increased in males with higher carbohydrate proportions (of total energy intake). In females, the risk of MetS was significantly elevated only in those with both the highest carbohydrate proportion and lowest fat proportion. A high carbohydrate proportion was associated with a higher prevalence of MetS in males, and a high carbohydrate proportion combined with a low fat proportion was associated with MetS in females. Our results indicate that reduction of excessive carbohydrate intake paired with an adequate fat intake, taking into consideration optimal types of fat, is useful for MetS prevention. Longitudinal studies are needed to clarify the optimal types and amounts of carbohydrate and fat proportions as well as the mechanism underlying these relationships. Copyright © 2017 Elsevier Ltd and European Society for Clinical Nutrition and Metabolism. All rights reserved.

The effect of dietary carbohydrate on gastroesophageal reflux disease.

Science.gov (United States)

Wu, Keng-Liang; Kuo, Chung-Mou; Yao, Chih-Chien; Tai, Wei-Chen; Chuah, Seng-Kee; Lim, Chee-Sang; Chiu, Yi-Chun

2018-01-12

Acid changes in gastroesophageal reflux with vary component in the food have less been studied, especially carbohydrate. We plan to clarify the effect of different carbohydrate density on low esophageal acid and reflux symptoms of patients with gastroesophgeal reflux disease. Twelve patients (52 ± 12 years old; five female) with gastroesophageal reflux disease were recruited for the prospective crossover study. Each patient was invited for panendoscope, manometry and 24 h pH monitor. The two formulated liquid meal, test meal A: 500 ml liquid meal (containing 84.8 g carbohydrate) and B: same volume liquid meal (but 178.8 g carbohydrate) were randomized supplied as lunch or dinner. Reflux symptoms were recorded. There are significant statistic differences in more Johnson-DeMeester score (p = 0.019), total reflux time (%) (p = 0.028), number of reflux periods (p = 0.026) and longest reflux (p = 0.015) after high carbohydrate diet than low carbohydrate. Total reflux time and number of long reflux periods more than 5 min are significant more after high carbohydrate diet. More acid reflux symptoms are found after high carbohydrate diet. High carbohydrate diet could induce more acid reflux in low esophagus and more reflux symptoms in patients with gastroesophageal reflux disease. Copyright © 2018. Published by Elsevier B.V.

Acute Effects of Carbohydrate Supplementation on Intermittent Sports Performance.

Science.gov (United States)

Baker, Lindsay B; Rollo, Ian; Stein, Kimberly W; Jeukendrup, Asker E

2015-07-14

Intermittent sports (e.g., team sports) are diverse in their rules and regulations but similar in the pattern of play; that is, intermittent high-intensity movements and the execution of sport-specific skills over a prolonged period of time (~1-2 h). Performance during intermittent sports is dependent upon a combination of anaerobic and aerobic energy systems, both of which rely on muscle glycogen and/or blood glucose as an important substrate for energy production. The aims of this paper are to review: (1) potential biological mechanisms by which carbohydrate may impact intermittent sport performance; (2) the acute effects of carbohydrate ingestion on intermittent sport performance, including intermittent high-intensity exercise capacity, sprinting, jumping, skill, change of direction speed, and cognition; and (3) what recommendations can be derived for carbohydrate intake before/during exercise in intermittent sports based on the available evidence. The most researched intermittent sport is soccer but some sport-specific studies have also been conducted in other sports (e.g., rugby, field hockey, basketball, American football, and racquet sports). Carbohydrate ingestion before/during exercise has been shown in most studies to enhance intermittent high-intensity exercise capacity. However, studies have shown mixed results with regards to the acute effects of carbohydrate intake on sprinting, jumping, skill, change of direction speed, and cognition. In most of these studies the amount of carbohydrate consumed was ~30-60 g/h in the form of a 6%-7% carbohydrate solution comprised of sucrose, glucose, and/or maltodextrin. The magnitude of the impact that carbohydrate ingestion has on intermittent sport performance is likely dependent on the carbohydrate status of the individual; that is, carbohydrate ingestion has the greatest impact on performance under circumstances eliciting fatigue and/or hypoglycemia. Accordingly, carbohydrate ingestion before and during a game

Very low-carbohydrate versus isocaloric high-carbohydrate diet in dietary obese rats.

Science.gov (United States)

Axen, Kathleen V; Axen, Kenneth

2006-08-01

The effects of a very low-carbohydrate (VLC), high-fat (HF) dietary regimen on metabolic syndrome were compared with those of an isocaloric high-carbohydrate (HC), low-fat (LF) regimen in dietary obese rats. Male Sprague-Dawley rats, made obese by 8 weeks ad libitum consumption of an HF diet, developed features of the metabolic syndrome vs. lean control (C) rats, including greater visceral, subcutaneous, and hepatic fat masses, elevated plasma cholesterol levels, impaired glucose tolerance, and fasting and post-load insulin resistance. Half of the obese rats (VLC) were then fed a popular VLC-HF diet (Weeks 9 and 10 at 5% and Weeks 11 to 14 at 15% carbohydrate), and one-half (HC) were pair-fed an HC-LF diet (Weeks 9 to 14 at 60% carbohydrate). Energy intakes of pair-fed VLC and HC rats were less than C rats throughout Weeks 9 to 14. Compared with HC rats, VLC rats exhibited impaired insulin and glycemic responses to an intraperitoneal glucose load at Week 10 and lower plasma triacylglycerol levels but retarded loss of hepatic, retroperitoneal, and total body fat at Week 14. VLC, HC, and C rats no longer differed in body weight, plasma cholesterol, glucose tolerance, or fasting insulin resistance at Week 14. Progressive decreases in fasting insulin resistance in obese groups paralleled concomitant reductions in hepatic, retroperitoneal, and total body fat. When energy intake was matched, the VLC-HF diet provided no advantage in weight loss or in improving those components of the metabolic syndrome induced by dietary obesity and may delay loss of hepatic and visceral fat as compared with an HC-LF diet.

DoGlycans-Tools for Preparing Carbohydrate Structures for Atomistic Simulations of Glycoproteins, Glycolipids, and Carbohydrate Polymers for GROMACS

DEFF Research Database (Denmark)

Danne, Reinis; Poojari, Chetan; Martinez-Seara, Hector

2017-01-01

Carbohydrates constitute a structurally and functionally diverse group of biological molecules and macromolecules. In cells they are involved in, e.g., energy storage, signaling, and cell-cell recognition. All of these phenomena take place in atomistic scales, thus atomistic simulation would...... be the method of choice to explore how carbohydrates function. However, the progress in the field is limited by the lack of appropriate tools for preparing carbohydrate structures and related topology files for the simulation models. Here we present tools that fill this gap. Applications where the tools...

Carbohydrate absorption from one serving of fruit juice in young children: age and carbohydrate composition effects.

Science.gov (United States)

Nobigrot, T; Chasalow, F I; Lifshitz, F

1997-04-01

To test the hypotheses that: the efficiency of carbohydrate absorption in childhood increases with age, and decreased carbohydrate absorption occurs more frequently with juices containing more fructose than glucose and/or sorbitol than with juices which contain equal amounts of fructose and glucose and are sorbitol-free. One hundred and four healthy children were recruited from the Ambulatory Center at Maimonides Children's Center. They were assigned to one of three age groups: approximately 1, 3 and 5 years of age. Each child received one age-specific dose (by randomization) of one of four juices: a) pear juice which contains fructose in excess to glucose and a large amount of sorbitol; b) apple juice which is similar to pear juice in its fructose to glucose ratio but contains four times less sorbitol than pear juice; c) white grape juice or d) purple grape juice both of which contain equal amounts of fructose and glucose and are sorbitol-free. Breath hydrogen excretion (BH2) was utilized as the index of carbohydrate absorption. It was measured in fasting children and at 30-minute intervals for 3 hours after drinking the single serving of juice. Multiple breath hydrogen related parameters were quantified and results were expressed as: BH2 peak, area under the curve, and degree of carbohydrate malabsorption. After the test, parents completed a questionnaire and recorded signs and symptoms of intestinal malabsorption for 24 hours. Pear juice related BH2 levels were significantly higher among children 1 and 3 years of age as compared to the levels achieved after the other juices. Apple juice related BH2 levels were significantly higher only among the youngest age group of children. There was no significant difference in carbohydrate absorption among the 5 year old children regardless of the juice consumed. Incomplete carbohydrate absorption (BH2 peak above 20 ppm) occurred more frequently after pear juice consumption (84%) than after apple juice (41%) or grape juice

Single tag for total carbohydrate analysis.

Science.gov (United States)

Anumula, Kalyan Rao

2014-07-15

Anthranilic acid (2-aminobenzoic acid, 2-AA) has the remarkable property of reacting rapidly with every type of reducing carbohydrate. Reactivity of 2-AA with carbohydrates in aqueous solutions surpasses all other tags reported to date. This unique capability is attributed to the strategically located -COOH which accelerates Schiff base formation. Monosaccharides, oligosaccharides (N-, O-, and lipid linked and glycans in secretory fluids), glycosaminoglycans, and polysaccharides can be easily labeled with 2-AA. With 2-AA, labeling is simple in aqueous solutions containing proteins, peptides, buffer salts, and other ingredients (e.g., PNGase F, glycosidase, and transferase reaction mixtures). In contrast, other tags require relatively pure glycans for labeling in anhydrous dimethyl sulfoxide-acetic acid medium. Acidic conditions are known to cause desialylation, thus requiring a great deal of attention to sample preparation. Simpler labeling is achieved with 2-AA within 30-60 min in mild acetate-borate buffered solution. 2-AA provides the highest sensitivity and resolution in chromatographic methods for carbohydrate analysis in a simple manner. Additionally, 2-AA is uniquely qualified for quantitative analysis by mass spectrometry in the negative mode. Analyses of 2-AA-labeled carbohydrates by electrophoresis and other techniques have been reported. Examples cited here demonstrate that 2-AA is the universal tag for total carbohydrate analysis. Copyright © 2014 Elsevier Inc. All rights reserved.

A comparison of low-carbohydrate vs. high-carbohydrate diets: energy restriction, nutrient quality and correlation to body mass index.

Science.gov (United States)

Bowman, Shanthy A; Spence, Joseph T

2002-06-01

To evaluate free-living adults' diets that ranged from very low to high amounts of carbohydrate for their energy content, nutritional quality and correlation to Body Mass Index. Adults ages 19 years and older, who had complete dietary intake data on day-1 of the USDA's 1994 to 1996 Continuing Survey of Food Intakes by Individuals (CSFII 1994-1996), were divided into four groups--very low, low, moderate and high carbohydrate--based on the percent total energy from carbohydrate. Mean energy, nutrient, food intakes and Body Mass Index values were compared among the groups. SUDAAN software package was used for the data analysis and pair-wise mean comparisons (p low-fat foods, grain products and fruits. This group also had the lowest sodium intake. Adults eating a high-carbohydrate diet are more likely to have Body Mass Index values below 25. A study of diets of free-living adults in the U.S. showed that diets high in carbohydrate were both energy restrictive and nutritious and may be adopted for successful weight management.

The case for low carbohydrate diets in diabetes management

Directory of Open Access Journals (Sweden)

McFarlane Samy I

2005-07-01

Full Text Available Abstract A low fat, high carbohydrate diet in combination with regular exercise is the traditional recommendation for treating diabetes. Compliance with these lifestyle modifications is less than satisfactory, however, and a high carbohydrate diet raises postprandial plasma glucose and insulin secretion, thereby increasing risk of CVD, hypertension, dyslipidemia, obesity and diabetes. Moreover, the current epidemic of diabetes and obesity has been, over the past three decades, accompanied by a significant decrease in fat consumption and an increase in carbohydrate consumption. This apparent failure of the traditional diet, from a public health point of view, indicates that alternative dietary approaches are needed. Because carbohydrate is the major secretagogue of insulin, some form of carbohydrate restriction is a prima facie candidate for dietary control of diabetes. Evidence from various randomized controlled trials in recent years has convinced us that such diets are safe and effective, at least in short-term. These data show low carbohydrate diets to be comparable or better than traditional low fat high carbohydrate diets for weight reduction, improvement in the dyslipidemia of diabetes and metabolic syndrome as well as control of blood pressure, postprandial glycemia and insulin secretion. Furthermore, the ability of low carbohydrate diets to reduce triglycerides and to increase HDL is of particular importance. Resistance to such strategies has been due, in part, to equating it with the popular Atkins diet. However, there are many variations and room for individual physician planning. Some form of low carbohydrate diet, in combination with exercise, is a viable option for patients with diabetes. However, the extreme reduction of carbohydrate of popular diets (

Acute Effects of Carbohydrate Supplementation on Intermittent Sports Performance

Directory of Open Access Journals (Sweden)

Lindsay B. Baker

2015-07-01

Full Text Available Intermittent sports (e.g., team sports are diverse in their rules and regulations but similar in the pattern of play; that is, intermittent high-intensity movements and the execution of sport-specific skills over a prolonged period of time (~1–2 h. Performance during intermittent sports is dependent upon a combination of anaerobic and aerobic energy systems, both of which rely on muscle glycogen and/or blood glucose as an important substrate for energy production. The aims of this paper are to review: (1 potential biological mechanisms by which carbohydrate may impact intermittent sport performance; (2 the acute effects of carbohydrate ingestion on intermittent sport performance, including intermittent high-intensity exercise capacity, sprinting, jumping, skill, change of direction speed, and cognition; and (3 what recommendations can be derived for carbohydrate intake before/during exercise in intermittent sports based on the available evidence. The most researched intermittent sport is soccer but some sport-specific studies have also been conducted in other sports (e.g., rugby, field hockey, basketball, American football, and racquet sports. Carbohydrate ingestion before/during exercise has been shown in most studies to enhance intermittent high-intensity exercise capacity. However, studies have shown mixed results with regards to the acute effects of carbohydrate intake on sprinting, jumping, skill, change of direction speed, and cognition. In most of these studies the amount of carbohydrate consumed was ~30–60 g/h in the form of a 6%–7% carbohydrate solution comprised of sucrose, glucose, and/or maltodextrin. The magnitude of the impact that carbohydrate ingestion has on intermittent sport performance is likely dependent on the carbohydrate status of the individual; that is, carbohydrate ingestion has the greatest impact on performance under circumstances eliciting fatigue and/or hypoglycemia. Accordingly, carbohydrate ingestion before

Racemic carbohydrates - fact or fiction?

DEFF Research Database (Denmark)

Senning, Alexander Erich Eugen

2007-01-01

Chemical Abstracts Service has developed unsound practices in the naming and handling of simple carbohydrates such as aldopentoses 1, aldohexoses 2, and ketohexoses 3. Typically, the common name glucose is sometimes, inappropriately, interpreted as meaning DL-glucose DL-2d. Thus, a considerable...... number of CA names and registry numbers have been created for non-existing racemic carbohydrates and linked to irrelevant references which, moreover, in many cases cannot be retrieved by the SciFinder Scholar program....

Microalgal carbohydrates. An overview of the factors influencing carbohydrates production, and of main bioconversion technologies for production of biofuels

Energy Technology Data Exchange (ETDEWEB)

Markou, Giorgos; Georgakakis, Dimitris [Agricultural Univ. of Athens (Greece). Dept. of Natural Resources Management and Agricultural Engineering; Angelidaki, Irini [Technical Univ. of Denmark, Lyngby (Denmark). Dept. of Environmental Engineering

2012-11-15

Microalgal biomass seems to be a promising feedstock for biofuel generation. Microalgae have relative high photosynthetic efficiencies, high growth rates, and some species can thrive in brackish water or seawater and wastewater from the food- and agro-industrial sector. Today, the main interest in research is the cultivation of microalgae for lipids production to generate biodiesel. However, there are several other biological or thermochemical conversion technologies, in which microalgal biomass could be used as substrate. However, the high protein content or the low carbohydrate content of the majority of the microalgal species might be a constraint for their possible use in these technologies. Moreover, in the majority of biomass conversion technologies, carbohydrates are the main substrate for production of biofuels. Nevertheless, microalgae biomass composition could be manipulated by several cultivation techniques, such as nutrient starvation or other stressed environmental conditions, which cause the microalgae to accumulate carbohydrates. This paper attempts to give a general overview of techniques that can be used for increasing the microalgal biomass carbohydrate content. In addition, biomass conversion technologies, related to the conversion of carbohydrates into biofuels are discussed. (orig.)

Validation of lignocellulosic biomass carbohydrates determination via acid hydrolysis.

Science.gov (United States)

Zhou, Shengfei; Runge, Troy M

2014-11-04

This work studied the two-step acid hydrolysis for determining carbohydrates in lignocellulosic biomass. Estimation of sugar loss based on acid hydrolyzed sugar standards or analysis of sugar derivatives was investigated. Four model substrates (starch, holocellulose, filter paper and cotton) and three levels of acid/material ratios (7.8, 10.3 and 15.4, v/w) were studied to demonstrate the range of test artifacts. The method for carbohydrates estimation based on acid hydrolyzed sugar standards having the most satisfactory carbohydrate recovery and relative standard deviation. Raw material and the acid/material ratio both had significant effect on carbohydrate hydrolysis, suggesting the acid to have impacts beyond a catalyst in the hydrolysis. Following optimal procedures, we were able to reach a carbohydrate recovery of 96% with a relative standard deviation less than 3%. The carbohydrates recovery lower than 100% was likely due to the incomplete hydrolysis of substrates, which was supported by scanning electron microscope (SEM) images. Copyright © 2014 Elsevier Ltd. All rights reserved.

Impact of Carbohydrate Restriction on Healthy Adolescent Development.

Science.gov (United States)

Richmond, Hannah M; Duriancik, David M

2017-09-01

Carbohydrate-restricted diets are known for their impact on weight loss; however, research is still required to determine if low-carbohydrate diets are safe for adolescents. Carbohydrates directly stimulate an insulin response, and studies have recently shown that insulin and binding to respective insulin receptors (IRs) are critical in Kisspeptin (Kiss1) neuronal development. These neurons directly stimulate gonadotropin-releasing hormone, which activates the pituitary-gonadal axis during puberty. This information suggests that carbohydrate restriction may delay pubertal development in adolescents due to the impact on insulin and Kiss1 transcription. Studies have observed disturbed insulin metabolism in Type I Diabetics leading to delayed puberty, along with overfeeding stimulating early pubertal onset. Additionally, recent clinical trials bred female mice with IR deletions on Kiss1 neurons and observed delayed vaginal opening and estrus. Current animal research suggests low carbohydrate intake may delay pubertal onset, however additional research is required to determine outcome in human subjects. Copyright© of YS Medical Media ltd.

Whey or Casein Hydrolysate with Carbohydrate for Metabolism and Performance in Cycling.

Science.gov (United States)

Oosthuyse, T; Carstens, M; Millen, A M E

2015-07-01

The protein type most suitable for ingestion during endurance exercise is undefined. This study compared co-ingestion of either 15 g/h whey or casein hydrolysate with 63 g/h fructose: maltodextrin (0.8:1) on exogenous carbohydrate oxidation, exercise metabolism and performance. 2 h postprandial, 8 male cyclists ingested either: carbohydrate-only, carbohydrate-whey hydrolysate, carbohydrate-casein hydrolysate or placebo-water in a crossover, double-blind design during 2 h of exercise at 60%W max followed by a 16-km time trial. Data were evaluated by magnitude-based inferential statistics. Exogenous carbohydrate oxidation, measured from (13)CO2 breath enrichment, was not substantially influenced by co-ingestion of either protein hydrolysate. However, only co-ingestion of carbohydrate-casein hydrolysate substantially decreased (98% very likely decrease) total carbohydrate oxidation (mean±SD, 242±44; 258±47; 277±33 g for carbohydrate-casein, carbohydrate-whey and carbohydrate-only, respectively) and substantially increased (93% likely increase) total fat oxidation (92±14; 83±27; 73±19 g) compared with carbohydrate-only. Furthermore, only carbohydrate-casein hydrolysate ingestion resulted in a faster time trial (-3.6%; 90% CI: ±3.2%) compared with placebo-water (95% likely benefit). However, neither protein hydrolysate enhanced time trial performance when compared with carbohydrate-only. Under the conditions of this study, ingesting carbohydrate-casein, but not carbohydrate-whey hydrolysate, favourably alters metabolism during prolonged moderate-strenuous cycling without substantially altering cycling performance compared with carbohydrate-only. © Georg Thieme Verlag KG Stuttgart · New York.

Conversion of carbohydrates to levulinic acid esters

DEFF Research Database (Denmark)

2014-01-01

The present invention relates to the field of converting carbohydrates into levulinic acid, a platform chemical for many chemical end products. More specifically the invention relates to a method for converting carbohydrates such as mono-, di- or polysaccharides, obtained from for example biomass...

Total dissolved carbohydrate in Mahi river estuary

Digital Repository Service at National Institute of Oceanography (India)

Bhosle, N.B.; Rokade, M.A.; Zingde, M.D.

Total dissolved carbohydrate varied from 4.37-15 mg l-1 and 3.71-15.95 mg l-1 in the surface and bottom samples respectively. Highest concentration of carbohydrate was observed at station 1 which decreased downward upto Station 6 which showed...

Chiral reagents in glycosylation and modification of carbohydrates.

Science.gov (United States)

Wang, Hao-Yuan; Blaszczyk, Stephanie A; Xiao, Guozhi; Tang, Weiping

2018-02-05

Carbohydrates play a significant role in numerous biological events, and the chemical synthesis of carbohydrates is vital for further studies to understand their various biological functions. Due to the structural complexity of carbohydrates, the stereoselective formation of glycosidic linkages and the site-selective modification of hydroxyl groups are very challenging and at the same time extremely important. In recent years, the rapid development of chiral reagents including both chiral auxiliaries and chiral catalysts has significantly improved the stereoselectivity for glycosylation reactions and the site-selectivity for the modification of carbohydrates. These new tools will greatly facilitate the efficient synthesis of oligosaccharides, polysaccharides, and glycoconjugates. In this tutorial review, we will summarize these advances and highlight the most recent examples.

Carbohydrates and Depression.

Science.gov (United States)

Wurtman, Richard J.; Wurtman, Judith J.

1989-01-01

Describes the symptoms, such as appetite change and mood fluctuation, basic mechanisms, and some treatments of Seasonal Affective Disorder (SAD), Carbohydrate-Craving Obesity (CCO) and Premenstrual Syndrome (PMS). Provides several tables and diagrams, and three reading references. (YP)

Blood Triglycerides Levels and Dietary Carbohydrate Indices in Healthy Koreans

Directory of Open Access Journals (Sweden)

Hye Sook Min

2016-05-01

Full Text Available Objectives: Previous studies have obtained conflicting findings regarding possible associations between indices measuring carbohydrate intake and dyslipidemia, which is an established risk factor of coronary heart disease. In the present study, we examined cross-sectional associations between carbohydrate indices, including the dietary glycemic index (GI, glycemic load (GL, total amount of carbohydrates, and the percentage of energy from carbohydrates, and a range of blood lipid parameters. Methods: This study included 1530 participants (554 men and 976 women from 246 families within the Healthy Twin Study. We analyzed the associations using a generalized linear mixed model to control for familial relationships. Results: Levels of the Apo B were inversely associated with dietary GI, GL, and the amount of carbohydrate intake for men, but these relationships were not significant when fat-adjusted values of the carbohydrate indices were used. Triglyceride levels were positively associated with dietary GI and GL in women, and this pattern was more notable in overweight participants (body mass index [BMI] ≥25 kg/m2. However, total, low-density lipoprotein and high-density lipoprotein cholesterol levels were not significantly related with carbohydrate intake overall. Conclusions: Of the blood lipid parameters we investigated, only triglyceride levels were positively related with dietary carbohydrate indices among women participants in the Healthy Twin Study, with an interactive role observed for BMI. However, these associations were not observed in men, suggesting that the association between blood lipid levels and carbohydrate intake depends on the type of lipid, specific carbohydrate indices, gender, and BMI.

Carbohydrate deficient transferrin (CDT) in alcoholic cirrhosis: a kinetic study

DEFF Research Database (Denmark)

Henriksen, Jens Henrik; Grønbaek, M; Møller, Søren

1997-01-01

BACKGROUND/AIMS: Carbohydrate deficient transferrin has been introduced as a marker of excessive alcohol intake. The present study was undertaken in order to measure the circulating level of carbohydrate deficient transferrin in patients with alcoholic cirrhosis and to assess arteriovenous kinetics...... of carbohydrate deficient transferrin in liver and kidney. METHODS/RESULTS: The median value of serum carbohydrate deficient transferrin was 16.0 U/l in patients with alcoholic cirrhosis (n = 41), and this value was not significantly different from that of a normal control group (median 17.4 U/l, n = 55, ns......). Carbohydrate deficient transferrin was significantly higher in patients with cirrhosis and high current alcohol intake than in abstaining patients (20 vs. 14 U/l, p 50 g/day) had a significantly higher carbohydrate deficient transferrin...

Dietary non-digestible carbohydrates and the resistance to intestinal infections

NARCIS (Netherlands)

Bruggencate, ten S.J.M.

2004-01-01

Keywords: Non-digestible carbohydrates, prebiotics, inulin, FOS, calcium, microflora, short-chain fatty acids, mucin, intestinal permeability, salmonella, infection, rat, humanDietary non-digestible carbohydrates and the resistance to intestinal infectionsNon-digestible carbohydrates (NDC) stimulate

Evaluation of certain crop residues for carbohydrate and protein fractions by cornell net carbohydrate and protein system

Directory of Open Access Journals (Sweden)

Venkateswarulu Swarna

2015-06-01

Full Text Available Four locally available crop residues viz., jowar stover (JS, maize stover (MS, red gram straw (RGS and black gram straw (BGS were evaluated for carbohydrate and protein fractions using Cornell Net Carbohydrate and Protein (CNCP system. Lignin (% NDF was higher in legume straws as compared to cereal stovers while Non-structural carbohydrates (NSC (% DM followed the reverse trend. The carbohydrate fractions A and B1 were higher in BGS while B2 was higher in MS as compared to other crop residues. The unavailable cell wall fraction (C was higher in legume straws when compared to cereal stovers. Among protein fractions, B1 was higher in legume straws when compared to cereal stovers while B2 was higher in cereal stovers as compared to legume straws. Fraction B3 largely, bypass protein was highest in MS as compared to other crop residues. Acid detergent insoluble crude protein (ADICP (% CP or unavailable protein fraction C was lowest in MS and highest in BGS. It is concluded that MS is superior in nutritional value for feeding ruminants as compared to other crop residues.

Method for the direct determination of available carbohydrates in low-carbohydrate products using high-performance anion exchange chromatography.

Science.gov (United States)

Ellingson, David; Potts, Brian; Anderson, Phillip; Burkhardt, Greg; Ellefson, Wayne; Sullivan, Darryl; Jacobs, Wesley; Ragan, Robert

2010-01-01

An improved method for direct determination of available carbohydrates in low-level products has been developed and validated for a low-carbohydrate soy infant formula. The method involves modification of an existing direct determination method to improve specificity, accuracy, detection levels, and run times through a more extensive enzymatic digestion to capture all available (or potentially available) carbohydrates. The digestion hydrolyzes all common sugars, starch, and starch derivatives down to their monosaccharide components, glucose, fructose, and galactose, which are then quantitated by high-performance anion-exchange chromatography with photodiode array detection. Method validation consisted of specificity testing and 10 days of analyzing various spike levels of mixed sugars, maltodextrin, and corn starch. The overall RSD was 4.0% across all sample types, which contained within-day and day-to-day components of 3.6 and 3.4%, respectively. Overall average recovery was 99.4% (n = 10). Average recovery for individual spiked samples ranged from 94.1 to 106% (n = 10). It is expected that the method could be applied to a variety of low-carbohydrate foods and beverages.

Carbohydrate-active enzymes from pigmented Bacilli: a genomic approach to assess carbohydrate utilization and degradation

Directory of Open Access Journals (Sweden)

Henrissat Bernard

2011-09-01

Full Text Available Abstract Background Spore-forming Bacilli are Gram-positive bacteria commonly found in a variety of natural habitats, including soil, water and the gastro-intestinal (GI-tract of animals. Isolates of various Bacillus species produce pigments, mostly carotenoids, with a putative protective role against UV irradiation and oxygen-reactive forms. Results We report the annotation of carbohydrate active enzymes (CAZymes of two pigmented Bacilli isolated from the human GI-tract and belonging to the Bacillus indicus and B. firmus species. A high number of glycoside hydrolases (GHs and carbohydrate binding modules (CBMs were found in both isolates. A detailed analysis of CAZyme families, was performed and supported by growth data. Carbohydrates able to support growth as the sole carbon source negatively effected carotenoid formation in rich medium, suggesting that a catabolite repression-like mechanism controls carotenoid biosynthesis in both Bacilli. Experimental results on biofilm formation confirmed genomic data on the potentials of B. indicus HU36 to produce a levan-based biofilm, while mucin-binding and -degradation experiments supported genomic data suggesting the ability of both Bacilli to degrade mammalian glycans. Conclusions CAZy analyses of the genomes of the two pigmented Bacilli, compared to other Bacillus species and validated by experimental data on carbohydrate utilization, biofilm formation and mucin degradation, suggests that the two pigmented Bacilli are adapted to the intestinal environment and are suited to grow in and colonize the human gut.

Hepatocyte heterogeneity in the metabolism of carbohydrates.

Science.gov (United States)

Jungermann, K; Thurman, R G

1992-01-01

Periportal and perivenous hepatocytes possess different amounts and activities of the rate-generating enzymes of carbohydrate and oxidative energy metabolism and thus different metabolic capacities. This is the basis of the model of metabolic zonation, according to which periportal cells catalyze predominantly the oxidative catabolism of fatty and amino acids as well as glucose release and glycogen formation via gluconeogenesis, and perivenous cells carry out preferentially glucose uptake for glycogen synthesis and glycolysis coupled to liponeogenesis. The input of humoral and nervous signals into the periportal and perivenous zones is different; gradients of oxygen, substrates and products, hormones and mediators and nerve densities exist which are important not only for the short-term regulation of carbohydrate metabolism but also for the long-term regulation of zonal gene expression. The specialization of periportal and perivenous hepatocytes in carbohydrate metabolism has been well characterized. In vivo evidence is provided by the complex metabolic situation termed the 'glucose paradox' and by zonal flux differences calculated on the basis of the distribution of enzymes and metabolites. In vitro evidence is given by the different flux rates determined with classical invasive techniques, e.g. in periportal-like and perivenous-like hepatocytes in cell culture, in periportal- and perivenous-enriched hepatocyte populations and in perfused livers during orthograde and retrograde flow, as well as with noninvasive techniques using miniature oxygen electrodes, e.g. in livers perfused in either direction. Differences of opinion in the interpretation of studies with invasive and noninvasive techniques by the authors are discussed. The declining gradient in oxygen concentrations, the decreasing glucagon/insulin ratio and the different innervation could be important factors in the zonal expression of the genes of carbohydrate-metabolizing enzymes. While it is clear that

Cerebral carbohydrate cost of physical exertion in humans

DEFF Research Database (Denmark)

Dalsgaard, Mads K; Ogoh, Shigehiko; Dawson, Ellen A

2004-01-01

Above a certain level of cerebral activation the brain increases its uptake of glucose more than that of O(2), i.e., the cerebral metabolic ratio of O(2)/(glucose + 12 lactate) decreases. This study quantified such surplus brain uptake of carbohydrate relative to O(2) in eight healthy males who...... to exhaustion (15.8 +/- 1.7 min; P carbohydrate was not substantiated...... and, consequently, exhaustive exercise involves a brain surplus carbohydrate uptake of a magnitude comparable with its glycogen content....

Characterization of carbohydrate fractions and fermentation quality ...

African Journals Online (AJOL)

This experiment was carried out to evaluate the effects of adding fast-sile (FS), previous fermented juice (PFJ), sucrose (S) or fast-sile + sucrose (FS + S) on the fermentation characteristics and carbohydrates fractions of alfalfa silages by the Cornell net carbohydrates and proteins systems (CNCPS). Silages quality were well ...

The effect of stereochemistry on carbohydrate hydration in aqueous solutions

NARCIS (Netherlands)

Galema, Saskia Alexandra

1992-01-01

Although-carbohydrates are widely used, not much is known about the stereochemical aspects of hydration of carbohydrates. For D-aldohexoses, for example, there are eight different stereoisomers. Just how the hydroxy topology of a carbohydrate molecule influences the hydration behaviour in water is

The case for low carbohydrate diets in diabetes management.

Science.gov (United States)

Arora, Surender K; McFarlane, Samy I

2005-07-14

A low fat, high carbohydrate diet in combination with regular exercise is the traditional recommendation for treating diabetes. Compliance with these lifestyle modifications is less than satisfactory, however, and a high carbohydrate diet raises postprandial plasma glucose and insulin secretion, thereby increasing risk of CVD, hypertension, dyslipidemia, obesity and diabetes. Moreover, the current epidemic of diabetes and obesity has been, over the past three decades, accompanied by a significant decrease in fat consumption and an increase in carbohydrate consumption. This apparent failure of the traditional diet, from a public health point of view, indicates that alternative dietary approaches are needed. Because carbohydrate is the major secretagogue of insulin, some form of carbohydrate restriction is a prima facie candidate for dietary control of diabetes. Evidence from various randomized controlled trials in recent years has convinced us that such diets are safe and effective, at least in short-term. These data show low carbohydrate diets to be comparable or better than traditional low fat high carbohydrate diets for weight reduction, improvement in the dyslipidemia of diabetes and metabolic syndrome as well as control of blood pressure, postprandial glycemia and insulin secretion. Furthermore, the ability of low carbohydrate diets to reduce triglycerides and to increase HDL is of particular importance. Resistance to such strategies has been due, in part, to equating it with the popular Atkins diet. However, there are many variations and room for individual physician planning. Some form of low carbohydrate diet, in combination with exercise, is a viable option for patients with diabetes. However, the extreme reduction of carbohydrate of popular diets (<30 g/day) cannot be recommended for a diabetic population at this time without further study. On the other hand, the dire objections continually raised in the literature appear to have very little scientific

Carbohydrates in pig nutrition - Recent advances

DEFF Research Database (Denmark)

Knudsen, Knud Erik Bach; Lærke, Helle Nygaard; Ingerslev, Anne Krog

2016-01-01

The dietary carbohydrates are a diverse group of substances with a range of chemical, physical, and physiological properties. The primary chemical classification of carbohydrates is by molecular size (degree of polymerization [DP]), the type of linkage (α or β), and composition of individual...... to their potential for digestion by endogenous enzymes. Carbohydrates are the principal substrates for energy metabolism but also exert a number of other effects throughout the gastrointestinal tract. The starch structure as well as type and levels of DF influence, to a varying degree, the rate of starch digestion...... in the small intestine. Some types of soluble NSP are found to interact with intestinal mucus and produce a layer that significantly delays the transport of lipid digestion products. Potentially, the same may be the case for proteinous compounds. The delay in the transport of the nutrients to the gut...

[Specific problems posed by carbohydrate utilization in the rainbow trout].

Science.gov (United States)

Bergot, F

1979-01-01

Carbohydrate incorporation in trout diets arises problems both at digestive and metabolic levels. Digestive utilization of carbohydrate closely depends on their molecular weight. In addition, in the case of complex carbohydrates (starches), different factors such as the level of incorporation, the amount consumed and the physical state of starch influence the digestibility. The measurement of digestibility in itself is confronted with methodological difficulties. The way the feces are collected can affect the digestion coefficient. Dietary carbohydrates actually serve as a source of energy. Nevertheless, above a certain level in the diet, intolerance phenomena may appear. The question that arises now is to establish the optimal part that carbohydrates can take in the metabolizable energy of a given diet.

Dietary carbohydrates and triacylglycerol metabolism.

Science.gov (United States)

Roche, H M

1999-02-01

There is a growing body of scientific evidence which demonstrates that plasma triacylglycerol (TAG) concentration, especially in the postprandial state, is an important risk factor in relation to the development of CHD. Postprandial hypertriacylglycerolaemia is associated with a number of adverse metabolic risk factors, including the preponderance of small dense LDL, low HDL-cholesterol concentrations and elevated factor VII activity. Traditionally, a low-fat high-carbohydrate diet was used to prevent CHD because it effectively reduces plasma cholesterol concentrations, but this dietary regimen increases plasma TAG concentrations and reduces HDL-cholesterol concentrations. There is substantial epidemiological evidence which demonstrates that high plasma TAG and low plasma HDL concentrations are associated with an increased risk of CHD. Thus, there is reason for concern that the adverse effects of low-fat high-carbohydrate diets on TAG and HDL may counteract or negate the beneficial effect of reducing LDL-cholesterol concentrations. Although there have been no prospective studies to investigate whether reduced fat intake has an adverse effect on CHD, there is strong epidemiological evidence that reducing total fat intake is not protective against CHD. On the other hand, high-fat diets predispose to obesity, and central obesity adversely affects TAG metabolism. There is substantial evidence that in free-living situations low-fat high-carbohydrate diets lead to weight loss, which in turn will correct insulin resistance and plasma TAG metabolism. Clearly there is a need for prospective studies to resolve the issue as to whether low-fat high-carbohydrate diets play an adverse or beneficial role in relation to the development of CHD.

Chemoselective Reactions for the Synthesis of Glycoconjugates from Unprotected Carbohydrates

DEFF Research Database (Denmark)

Villadsen, Klaus; Martos Maldonado, Manuel Cristo; Jensen, Knud Jørgen

2017-01-01

Glycobiology is the comprehensive biological investigation of carbohydrates. The study of the role and function of complex carbohydrates often requires the attachment of carbohydrates to surfaces, their tagging with fluorophores, or their conversion into natural or non-natural glycoconjugates......, such as glycopeptides or glycolipids. Glycobiology and its “omics”, glycomics, require easy and robust chemical methods for the construction of these glycoconjugates. This review gives an overview of the rapidly expanding field of chemical reactions that selectively convert unprotected carbohydrates...

Multiple-Transportable Carbohydrate Effect on Long-Distance Triathlon Performance.

Science.gov (United States)

Rowlands, David S; Houltham, Stuart D

2017-08-01

The ingestion of multiple (2:1 glucose-fructose) transportable carbohydrate in beverages at high rates (>78 g·h) during endurance exercise enhances exogenous carbohydrate oxidation, fluid absorption, gut comfort, and performance relative to glucose alone. However, during long-distance endurance competition, athletes prefer a solid-gel-drink format, and the effect size of multiple-transportable carbohydrate is unknown. This study aimed to determine the effect of multiple-transportable carbohydrate on triathlon competition performance when ingested within bars, gels, and drinks. A double-blind randomized controlled trial was conducted within two national-body sanctioned half-ironman triathlon races held 3 wk apart in 74 well-trained male triathletes (18-60 yr; >2 yr competition experience). Carbohydrate comprising glucose/maltodextrin-fructose (2:1 ratio) or standard isocaloric carbohydrate (glucose/maltodextrin only) was ingested before (94 g) and during the cycle (2.5 g·km) and run (7.8 g·km) sections, averaging 78.6 ± 6.6 g·h, partitioned to bars (25%), gels (35%), and drink (40%). Postrace, 0- to 10-unit Likert-type scales were completed to assess gut comfort and energy. The trial returned low dropout rate (9%), high compliance, and sensitivity (typical error 2.2%). The effect of multiple-transportable carbohydrate on performance time was -0.53% (95% confidence interval = -1.30% to 0.24%; small benefit threshold = -0.54%), with likelihood-based risk analysis supporting adoption (benefit-harm ratio = 48.9%:0.3%; odds ratio = 285:1). Covariate adjustments for preexercise body weight and heat stress had negligible impact performance. Multiple-transportable carbohydrate possibly lowered nausea during the swim and bike; otherwise, effects on gut comfort and perceived energy were negligible. Multiple-transportable (2:1 maltodextrin/glucose-fructose) compared with single-transportable carbohydrate ingested in differing format provided a small benefit to long

Mixed drink increased carbohydrate oxidation but not performance ...

African Journals Online (AJOL)

Kathryn van Boom

... carbohydrate intake is hypothesised to provide additional substrate for oxidation[3] ... performance is attained when a multiple carbohydrate drink is ingested. ..... and often intense exercise, such as can be seen in events such as the Tour de ...

Carbohydrates in Colobanthus quitensis and Deschampsia antarctica

Directory of Open Access Journals (Sweden)

Agnieszka I. Piotrowicz-Cieślak

2011-01-01

Full Text Available Eight to nineteen ethanol-soluble carbohydrate components were identified in vegetative tissues of Colobanthus quitensis and Deschampsia antarctica. The analysed carbohydrates included: monosaccharides, cyclitols, galactosyl cyclitols, raffinose family oligosaccharides, lichnose family oligosaccharides, kestose family oligosaccharides. The analysed vegetative tissues accumulated from 447 to 139 mg/g d.m. soluble carbohydrates in Colobanthus quitensis, Deschampsia antarctica respectively. The raffinose family oligosaccharides constituted 53.3% in Colobanthus quitensis of the identified soluble carbohydrate component pool. Vegetative tissues accumulated starch in Colobanthus quitensis 20.6 mg/g d.m. and 261.6 mg/g d.m. in Deschampsia antarctica. Anatomical and ultrastructural observations of vegetative part of Colobanthus quitensis and Deschmpsia antarctica revealed the presence of various ergastic materials in intercellular spaces, cell walls and protoplasts. Various parts of these plants contain insoluble, PAS positive polysaccharides in intercellular spaces and in cell walls. Chloroplasts of analysed tissues contained starch. Less starch was visible in young, growing parts of shoots of Colobanthus quitensis and Deschmpsia antarctica, more starch appears in mature, differentiated parts.

Carbohydrate secretion by phototrophic communities in tidal sediments

NARCIS (Netherlands)

de Winder, B.; Staats, N.; Stal, L.J.; Paterson, D.M.

1999-01-01

Two different benthic phototrophic communities on tidal flats were investigated for their carbohydrate content and distribution. Carbohydrates were analysed as two operationally defined fractions, related to the difficulty of extraction from the sediment matrix. Water-soluble (colloidal) and EDTA-

Carbohydrates: How Carbs Fit into a Healthy Diet

Science.gov (United States)

... obesity. Carbohydrates are an essential part of a healthy diet, and provide many important nutrients. Still, not all carbs are created equal. Here's how to make healthy carbohydrates work in a balanced diet: Emphasize fiber-rich fruits and vegetables. Aim for ...

Importance of low carbohydrate diets in diabetes management

Directory of Open Access Journals (Sweden)

Hall RM

2016-03-01

Full Text Available Rosemary M Hall, Amber Parry Strong, Jeremy D KrebsCentre for Endocrine, Diabetes and Obesity Research, Capital and Coast District Health Board, Wellington, New Zealand Abstract: Dietary strategies are fundamental in the management of diabetes. Historically, strict dietary control with a low carbohydrate diet was the only treatment option. With increasingly effective medications, the importance of dietary change decreased. Recommendations focused on reducing dietary fat to prevent atherosclerotic disease, with decreasing emphasis on the amount and quality of carbohydrate. As the prevalence of obesity and diabetes escalates, attention has returned to the macronutrient composition of the diet. Very low carbohydrate diets (VLCD's have demonstrated effective initial weight loss and improvement in glycemic control, but difficult long-term acceptability and worsening lipid profile. Modifications to the very low carbohydrate (VLC have included limiting saturated fat and increasing carbohydrate (CHO and protein. Reducing saturated fat appears pivotal in reducing low-density lipoprotein (LDL cholesterol and may mitigate adverse effects of traditional VLCD's. Increased dietary protein enhances satiety, reduces energy intake, and improves glycemic homeostasis, but without sustained improvements in glycemic control or cardiovascular risk over and above the effect of weight loss. Additionally, recent studies in type 1 diabetes mellitus suggest promising benefits to diabetes control with low carbohydrate diets, without concerning effects on ketosis or hypoglycemia. Dietary patterns may highlight pertinent associations. For example, Mediterranean-style and paleolithic-type diets, low in fat and carbohydrate, are associated with reduced body weight and improved glycemic and cardiovascular outcomes in type 2 diabetes mellitus (T2DM. A feature of these dietary patterns is low refined CHO and sugar and higher fiber, and it is possible that increasing sugar

[Systematic evaluation of retention behavior of carbohydrates in hydrophilic interaction liquid chromatography].

Science.gov (United States)

Fu, Qing; Wang, Jun; Liang, Tu; Xu, Xiaoyong; Jin, Yu

2013-11-01

A systematic evaluation of retention behavior of carbohydrates in hydrophilic interaction liquid chromatography (HILIC) was performed. The influences of mobile phase, stationary phase and buffer salt on the retention of carbohydrates were investigated. According to the results, the retention time of carbohydrates decreased as the proportion of acetonitrile in mobile phase decreased. Increased time of carbohydrates was observed as the concentration of buffer salt in mobile phase increased. The retention behavior of carbohydrates was also affected by organic solvent and HILIC stationary phase. Furthermore, an appropriate retention equation was used in HILIC mode. The retention equation lnk = a + blnC(B) + cC(B) could quantitatively describe the retention factors of carbohydrates of plant origin with good accuracy: the relative error of the predicted time to actual time was less than 0.3%. The evaluation results could provide guidance for carbohydrates to optimize the experimental conditions in HILIC method development especially for carbohydrate separation

Particulate carbohydrate in the euphotic zone of the Bay of Bengal

Digital Repository Service at National Institute of Oceanography (India)

Bhosle, N; De; Shirodkar, P.V.; Reddy, C.V.G.

Particulate matter collected from the Bay of Bengal was analysed for carbohydrate and chlorophyll a. The distribution of chlorophyll a was different from that of carbohydrate. Chlorophyll a increased from north to south, whereas carbohydrate levels...

Chemical Changes in Carbohydrates Produced by Thermal Processing.

Science.gov (United States)

Hoseney, R. Carl

1984-01-01

Discusses chemical changes that occur in the carbohydrates found in food products when these products are subjected to thermal processing. Topics considered include browning reactions, starch found in food systems, hydrolysis of carbohydrates, extrusion cooking, processing of cookies and candies, and alterations in gums. (JN)

Using structure to inform carbohydrate binding module function

NARCIS (Netherlands)

Abbott, D. Wade; Lammerts van Bueren, Alicia

2014-01-01

Generally, non-catalytic carbohydrate binding module (CBM) specificity has been shown to parallel the catalytic activity of the carbohydrate active enzyme (CAZyme) module it is appended to. With the rapid expansion in metagenomic sequence space for the potential discovery of new CBMs in addition to

[Soil carbohydrates: their determination methods and indication functions].

Science.gov (United States)

Zhang, Wei; Xie, Hongtu; He, Hongbo; Zheng, Lichen; Wang, Ge

2006-08-01

Soil carbohydrates are the important component of soil organic matter, and play an important role in soil aggregation formation. Their hydrolysis methods involve sulfur acid (H2SO4), hydrochloric acid (HCl), and trifluoroacetic acid (TFA) hydrolysis, and their determination methods include colorimetry, gas-liquid chromatography (GLC) , high performance liquid chromatography (HPLC), and high performance anion-exchange chromatography with pulsed amperometric detection (HPAE-PAD). This paper summarized the methods of carbohydrates' hydrolysis, purification and detection, with focus on the derived methods of GLC, and briefly introduced the indication functions of carbohydrates in soil organic matter turnover.

Recent Progress in Chemical and Chemoenzymatic Synthesis of Carbohydrates

Science.gov (United States)

Muthana, Saddam; Cao, Hongzhi; Chen, Xi

2011-01-01

Summary The important roles that carbohydrates play in biological processes and their potential application in diagnosis, therapeutics, and vaccine development have made them attractive synthetic targets. Despite ongoing challenges, tremendous progresses have been made in recent years for the synthesis of carbohydrates. The chemical glycosylation methods have become more sophisticated and the synthesis of oligosaccharides has become more predictable. Simplified one-pot glycosylation strategy and automated synthesis are increasingly used to obtain biologically important glycans. On the other hand, chemoenzymatic synthesis continues to be a powerful alternative for obtaining complex carbohydrates. This review highlights recent progress in chemical and chemoenzymatic synthesis of carbohydrates with a particular focus on the methods developed for the synthesis of oligosaccharides, polysaccharides, glycolipids, and glycosylated natural products. PMID:19833544

Comparing the responses of rumen ciliate protozoa and bacteria to excess carbohydrate.

Science.gov (United States)

Teixeira, César R V; Lana, Rogério de Paula; Tao, Junyi; Hackmann, Timothy J

2017-06-01

When given excess carbohydrate, certain microbial species respond by storing energy (synthesizing reserve carbohydrate), but other species respond by dissipating the energy as heat (spilling energy). To determine the importance of these responses in the rumen microbial community, this study quantified the responses of mixed ciliate protozoa vs bacteria to glucose. We hypothesized that ciliates would direct more glucose to synthesis of reserve carbohydrate (and less to energy spilling) than would bacteria. Ciliates and bacteria were isolated from rumen fluid using filtration and centrifugation, resuspended in nitrogen-free buffer to limit growth, and dosed with 5 mM glucose. Compared with bacteria, ciliates consumed glucose >3-fold faster and synthesized reserve carbohydrate 4-fold faster. They incorporated 53% of glucose carbon into reserve carbohydrate-nearly double the value (27%) for bacteria. Energy spilling was not detected for ciliates, as all heat production (104%) was accounted by synthesis of reserve carbohydrate and endogenous metabolism. For bacteria, reserve carbohydrate and endogenous metabolism accounted for only 68% of heat production, and spilling was detected within 11 min of dosing glucose. These results suggest that ciliates alter the course of ruminal carbohydrate metabolism by outcompeting bacteria for excess carbohydrate, maximizing reserve carbohydrate synthesis, and minimizing energy spilling. © FEMS 2017. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

Comments on the reactions of carbohydrate peroxy radicals in relation to the lyoluminescent behaviour of irradiated carbohydrates

International Nuclear Information System (INIS)

Baugh, P.J.; Mahjani, M.G.

1977-01-01

Reference is made to recent work on lyoluminescence: the emission of visible light from irradiated tissue equivalent solids such as carbohydrates when dissolved in aqueous solutions (Atari et al., Radiat. Effects; 17:45(1973); and ibid.; 20: 135 (1973); and Baugh et al., Int.J.Radiat.Phys. Chem.(in press)). In the present communication the consequences of the fast elimination of the hydroperoxy radicals from carbohydrate peroxy radicals are considered in a further study of the chemical reactions involved. (U.K.)

Determining a carbohydrate profile for Hansenula polymorpha

Science.gov (United States)

Petersen, G. R.

1985-01-01

The determination of the levels of carbohydrates in the yeast Hansenula polymorpha required the development of new analytical procedures. Existing fractionation and analytical methods were adapted to deal with the problems involved with the lysis of whole cells. Using these new procedures, the complete carbohydrate profiles of H. polymorpha and selected mutant strains were determined and shown to correlate favourably with previously published results.

Characterization of immobilized post-carbohydrate meal salivary α ...

African Journals Online (AJOL)

The effect of experimental parameters like pH, temperature and substrate concentration on the activity of the immobilized post-carbohydrate meal salivary ... of immobilized post-carbohydrate meal salivary α-amylase in this study show that immobilization had no significant effect on the enzyme and compared to kinetic ...

Carbohydrate modified polysiloxanes, 3 - Solution properties of carbohydrate-polysiloxane conjugates in toluene

NARCIS (Netherlands)

Loos, Katja; Jonas, Gerd; Stadler, Reimund

2001-01-01

High molecular weight poly(hydromethyl-co-dimethyl) siloxanes containing 0.6 and 3 mol-% of Si-H units are polar functionalized by the addition of various mono-, di- and oligosaccharides. Due to the hydrogen bond interaction between the carbohydrate moieties, the solution properties are strongly

Effects of caffeine and carbohydrate mouth rinses on repeated sprint performance.

Science.gov (United States)

Beaven, C Martyn; Maulder, Peter; Pooley, Adrian; Kilduff, Liam; Cook, Christian

2013-06-01

Our purpose was to examine the effectiveness of carbohydrate and caffeine mouth rinses in enhancing repeated sprint ability. Previously, studies have shown that a carbohydrate mouth rinse (without ingestion) has beneficial effects on endurance performance that are related to changes in brain activity. Caffeine ingestion has also demonstrated positive effects on sprint performance. However, the effects of carbohydrate or caffeine mouth rinses on intermittent sprints have not been examined previously. Twelve males performed 5 × 6-s sprints interspersed with 24 s of active recovery on a cycle ergometer. Twenty-five milliliters of either a noncaloric placebo, a 6% glucose, or a 1.2% caffeine solution was rinsed in the mouth for 5 s prior to each sprint in a double-blinded and balanced cross-over design. Postexercise maximal heart rate and perceived exertion were recorded, along with power measures. A second experiment compared a combined caffeine-carbohydrate rinse with carbohydrate only. Compared with the placebo mouth rinse, carbohydrate substantially increased peak power in sprint 1 (22.1 ± 19.5 W; Cohen's effect size (ES), 0.81), and both caffeine (26.9 ± 26.9 W; ES, 0.71) and carbohydrate (39.1 ± 25.8 W; ES, 1.08) improved mean power in sprint 1. Experiment 2 demonstrated that a combination of caffeine and carbohydrate improved sprint 1 power production compared with carbohydrate alone (36.0 ± 37.3 W; ES, 0.81). We conclude that carbohydrate and (or) caffeine mouth rinses may rapidly enhance power production, which could have benefits for specific short sprint exercise performance. The ability of a mouth-rinse intervention to rapidly improve maximal exercise performance in the absence of fatigue suggests a central mechanism.

Radiation chemistry of carbohydrates and of the sugar moiety in DNA

International Nuclear Information System (INIS)

Sonntag, C. von

1979-01-01

The free radical chemistry of carbohydrates as studied by radiation techniques is briefly reviewed. In aqueous solutions OH radicals and H atoms abstract carbon-bound H atoms to give the primary carbohydrate radicals which can undergo a number of elimination and rearrangement reactions leading to secondary carbohydrate radicals. Oxygen can suppress these elimination and rearrangement reactions by converting the primary carbohydrate radicals into the corresponding peroxyl radicals. The reactions leading to the observed products are discussed. In the solid state a few carbohydrates show radiation-induced chain reactions which are of preparative interest. Hydroxyl radical attack at the sugar moiety of DNA eventually leads to DNA strand breaks and to alkali-labile sites. (Auth.)

Mixed drink increased carbohydrate oxidation but not performance ...

African Journals Online (AJOL)

... improvement in 40 km time trial time between an isocaloric GP-only or a GP and fructose drink, and no differences in any of the measured variables other than exogenous carbohydrate oxidation at 90 minutes during the pre-time trial steady state ride. Keywords: multiple carbohydrate, cycling, endurance, glucose, fructose ...

The effects of carbohydrate variation in isocaloric diets on glycogenolysis and gluconeogenesis in healthy men

NARCIS (Netherlands)

Bisschop, P. H.; Pereira Arias, A. M.; Ackermans, M. T.; Endert, E.; Pijl, H.; Kuipers, F.; Meijer, A. J.; Sauerwein, H. P.; Romijn, J. A.

2000-01-01

To evaluate the effect of dietary carbohydrate content on postabsorptive glucose metabolism, we quantified gluconeogenesis and glycogenolysis after 11 days of high carbohydrate (85% carbohydrate), control (44% carbohydrate), and very low carbohydrate (2% carbohydrate) diets in six healthy men. Diets

The effects of carbohydrate variation in isocaloric diets on glycogenolysis and gluconeogenesis in healthy men

NARCIS (Netherlands)

Bisschop, PH; Arias, AMP; Ackermans, MT; Endert, E; Pijl, H; Kuipers, F; Meijer, AJ; Sauerwein, HP; Romijn, JA

To evaluate the effect of dietary carbohydrate content on postabsorptive glucose metabolism, we quantified gluconeogenesis and glycogenolysis after 11 days of high carbohydrate (85% carbohydrate), control (44% carbohydrate), and very low carbohydrate (2% carbohydrate) diets in six healthy men. Diets

Digestion and metabolism of carbohydrates in fish

OpenAIRE

Abro, Rani

2014-01-01

This thesis deals with the digestion and metabolism of carbohydrates in Arctic charr, Eurasian perch and tilapia. Two sources of carbohydrates, native starch (wheat) and chitin (zygomycete biomass), were evaluated. Gut tissue of Arctic charr displayed significant chitinase activity, of both endo- and exo-chitinase forms. Moreover, the distribution pattern along the gastrointestinal tract of Arctic charr differed between endo-chitinase and exo-chitinase. The endo-chitinase activity in sto...

Sports Nutrition for the Primary Care Physician: The Importance of Carbohydrate.

Science.gov (United States)

Wheeler, Keith B.

1989-01-01

Discusses the relationship between nutrition and fatigue and how carbohydrates and timing of carbohydrate consumption can affect fatigued athletes. Nutrition plays a significant role in successful training and competition. Key concerns are the specific needs of athletes for carbohydrates before, during, and after exercise. (Author/SM)

Carbohydrate Microarrays in Plant Science

DEFF Research Database (Denmark)

Fangel, Jonatan Ulrik; Pedersen, H.L.; Vidal-Melgosa, S.

2012-01-01

Almost all plant cells are surrounded by glycan-rich cell walls, which form much of the plant body and collectively are the largest source of biomass on earth. Plants use polysaccharides for support, defense, signaling, cell adhesion, and as energy storage, and many plant glycans are also important...... industrially and nutritionally. Understanding the biological roles of plant glycans and the effective exploitation of their useful properties requires a detailed understanding of their structures, occurrence, and molecular interactions. Microarray technology has revolutionized the massively high...... for plant research and can be used to map glycan populations across large numbers of samples to screen antibodies, carbohydrate binding proteins, and carbohydrate binding modules and to investigate enzyme activities....

Simple mucin-type carbohydrate antigens in major salivary glands

DEFF Research Database (Denmark)

Therkildsen, M H; Mandel, U; Thorn, J

1994-01-01

Simple mucin-type carbohydrate antigens Tn, sialosyl-Tn and T are often markers of neoplastic transformation and have very limited expression in normal tissues. We performed an immunohistological study of simple mucin-type carbohydrate antigens, including H and A variants, with well......-defined monoclonal antibodies (MAb) on frozen and paraffin-embedded normal salivary gland tissue from 22 parotid, 14 submandibular, six sublingual, and 13 labial glands to elucidate the simple mucin-type glycosylation pattern in relation to cyto- and histodifferentiation. The investigated carbohydrate structures...

High throughput screening of starch structures using carbohydrate microarrays

DEFF Research Database (Denmark)

Tanackovic, Vanja; Rydahl, Maja Gro; Pedersen, Henriette Lodberg

2016-01-01

In this study we introduce the starch-recognising carbohydrate binding module family 20 (CBM20) from Aspergillus niger for screening biological variations in starch molecular structure using high throughput carbohydrate microarray technology. Defined linear, branched and phosphorylated...

Characterization of carbohydrates in rainwater from the southeastern North Carolina.

Science.gov (United States)

Mullaugh, Katherine M; Byrd, Jade N; Avery, G Brooks; Mead, Ralph N; Willey, Joan D; Kieber, Robert J

2014-07-01

Carbohydrates have been widely reported in atmospheric aerosols, but have not previously been quantified in rainwater. We have identified and quantified a series of 11 specific compounds including monosaccharides (glucose, fructose, arabinose, galactose and pinitol), disaccharides (sucrose and trehalose), sugar alcohols (arabitol, dulcitol and mannitol) and the anhydrosaccharide levoglucosan. Rainwater analyzed in this study includes 52 distinct precipitation events in Wilmington, NC between June 2011 and October 2012. Our analysis indicates carbohydrates typically contribute carbohydrates reached as high as 5.8 μM, with glucose and sucrose typically being the predominant species. The distribution of carbohydrates exhibited a distinct seasonal pattern, with higher concentrations of most carbohydrates, especially sucrose, in spring and summer, driven primarily by increased biogenic inputs during the growing season. Concentrations of carbohydrates were an order of magnitude higher in storms of terrestrial origin compared to marine events, further supporting a terrestrial biogenic origin of most species. Sequential sampling of Hurricane Irene showed significant quantities of carbohydrates present at the end of the storm when air mass back trajectories traversed over land. The highest level of levoglucosan, a compound associated with biomass burning, was detected in rain with an air mass back trajectory that traveled over a region affected by wildfires. When compared to aerosol concentrations reported by others, the sugar concentrations in rain demonstrate wet deposition is an important removal mechanism of this water-soluble and bioavailable fraction of atmospheric particulate organic matter. Copyright © 2014 Elsevier Ltd. All rights reserved.

Nutrient and carbohydrate partitioning in sorghum stover

International Nuclear Information System (INIS)

Powell, J.M.; Hons, F.M.; McBee, G.G.

1991-01-01

Sorghum [Sorghum bicolor (L.) Moench] stover has been demonstrated to be a potential biomass energy source. Complete aboveground crop removal, however, can result in soil degradation. Differential dry matter, nutrient, and carbohydrate partitioning by sorghum cultivars may allow management strategies that return certain parts to the field while removing other portions for alternative uses, such as energy production. A field study was conducted to determine N,P,K, nonstructural carbohydrate, cellulose hemicellulose, and lignin distributions in stover of three diverse sorghum cultivars of differing harvest indices. Determinations were based on total vegetative biomass; total blades; total stalks; and upper middle, and lower blades and stalks. Concentrations of N and P were higher in blades than stalks and generally declines from upper to lower stover parts. Large carbohydrate and lignin concentration differences were observed on the basis of cultivar and stover part. Greater nutrient partitioning to the upper third of the intermediate and forage-type sorghum stovers was observed as compared to the conventional grain cultivar. Stover carbohydrates for all cultivars were mainly contained in the lower two-thirds of the stalk fraction. A system was proposed for returning upper stover portion to soil, while removing remaining portions for alternative uses

Assimilation, partitioning, and nonstructural carbohydrates in sweet compared with grain sorghum

International Nuclear Information System (INIS)

Vietor, D.M.; Miller, F.R.

1990-01-01

Nonstructural carbohydrate concentrations in stems are greater for sweet than grain sorghums [Sorghum bicolor (L.) Moench]. Knowledge of plant characteristics associated with high nonstructural carbohydrates in sweet sorghum will air efforts to increase nonstructural carbohydrates in grain sorghum stems. This study tested the hypothesis that variation of CO 2 assimilation rate, leaf area, branching at upper nodes, and partitioning of 14 C-labeled assimilate to main stems are associated with variation of stem nonstructural carbohydrates. A sweet (Atlas X Rio) and a grain (ATx623 X RTx5388) hybrid, stages near and after physiological maturity, and defoliation and gibberellic acid (GA 3 ) treatments provided sources of variation for study. Concentrations of nonstructural carbohydrates in lower and upper stems of the sweet hybrid were 1.4 and 2.7 times higher, respectively, than for the grain hybrid, after physiological maturity. Variation in branching, including 14 C-assimilate partitioning to branches, was not consistently associated with hybrid differences in stem nonstructural carbohydrates. Increased recovery (twofold) of 14 C-assimilate in roots and labeled leaves corresponded with lower percentages of 14 C-assimilate and lower concentrations of nonstructural carbohydrates in stems of the grain hybrid. Leaf areas and leaf CO 2 exchange rate were twice as great for the sweet hybrid. Although defoliation of the sweet hybrid minimized leaf area differences between hybrids, the sweet hybrid accumulated twice as much nonstructural carbohydrates in branches after physiological maturity. Greater potentials for CO 2 assimilation and for 14 C-assimilate accumulation in mature stem tissue were associated with higher levels of stem nonstructural carbohydrates in the sweet compared with the grain hybrid

Boronic acids for fluorescence imaging of carbohydrates.

Science.gov (United States)

Sun, Xiaolong; Zhai, Wenlei; Fossey, John S; James, Tony D

2016-02-28

"Fluorescence imaging" is a particularly exciting and rapidly developing area of research; the annual number of publications in the area has increased ten-fold over the last decade. The rapid increase of interest in fluorescence imaging will necessitate the development of an increasing number of molecular receptors and binding agents in order to meet the demand in this rapidly expanding area. Carbohydrate biomarkers are particularly important targets for fluorescence imaging given their pivotal role in numerous important biological events, including the development and progression of many diseases. Therefore, the development of new fluorescent receptors and binding agents for carbohydrates is and will be increasing in demand. This review highlights the development of fluorescence imaging agents based on boronic acids a particularly promising class of receptors given their strong and selective binding with carbohydrates in aqueous media.

A randomized trial of a low-carbohydrate diet for obesity.

Science.gov (United States)

Foster, Gary D; Wyatt, Holly R; Hill, James O; McGuckin, Brian G; Brill, Carrie; Mohammed, B Selma; Szapary, Philippe O; Rader, Daniel J; Edman, Joel S; Klein, Samuel

2003-05-22

Despite the popularity of the low-carbohydrate, high-protein, high-fat (Atkins) diet, no randomized, controlled trials have evaluated its efficacy. We conducted a one-year, multicenter, controlled trial involving 63 obese men and women who were randomly assigned to either a low-carbohydrate, high-protein, high-fat diet or a low-calorie, high-carbohydrate, low-fat (conventional) diet. Professional contact was minimal to replicate the approach used by most dieters. Subjects on the low-carbohydrate diet had lost more weight than subjects on the conventional diet at 3 months (mean [+/-SD], -6.8+/-5.0 vs. -2.7+/-3.7 percent of body weight; P=0.001) and 6 months (-7.0+/-6.5 vs. -3.2+/-5.6 percent of body weight, P=0.02), but the difference at 12 months was not significant (-4.4+/-6.7 vs. -2.5+/-6.3 percent of body weight, P=0.26). After three months, no significant differences were found between the groups in total or low-density lipoprotein cholesterol concentrations. The increase in high-density lipoprotein cholesterol concentrations and the decrease in triglyceride concentrations were greater among subjects on the low-carbohydrate diet than among those on the conventional diet throughout most of the study. Both diets significantly decreased diastolic blood pressure and the insulin response to an oral glucose load. The low-carbohydrate diet produced a greater weight loss (absolute difference, approximately 4 percent) than did the conventional diet for the first six months, but the differences were not significant at one year. The low-carbohydrate diet was associated with a greater improvement in some risk factors for coronary heart disease. Adherence was poor and attrition was high in both groups. Longer and larger studies are required to determine the long-term safety and efficacy of low-carbohydrate, high-protein, high-fat diets. Copyright 2003 Massachusetts Medical Society

Carbohydrate plasma expanders for passive tumor targeting

DEFF Research Database (Denmark)

Hoffmann, Stefan; Caysa, Henrike; Kuntsche, Judith

2013-01-01

The objective of this study was to investigate the suitability of carbohydrate plasma volume expanders as a novel polymer platform for tumor targeting. Many synthetic polymers have already been synthesized for targeted tumor therapy, but potential advantages of these carbohydrates include inexpen...... was characterized in human colon carcinoma xenograft bearing nude mice. A tumor specific accumulation of HES 450 was observed, which proves it’s potential as carrier for passive tumor targeting....

Impact of carbohydrates on weight regain.

Science.gov (United States)

Bosy-Westphal, Anja; Müller, Manfred J

2015-07-01

Research on obesity treatment has shifted its focus from weight loss to weight-loss maintenance strategies. The conventional approach of a low-fat diet is challenged by insights from glycemic effects of carbohydrates on body weight regulation. Metabolic and endocrine adaptations to weight loss that contribute to weight regain involve reduced energy expenditure, increased insulin sensitivity, and enhanced orexigenic signals. This review summarizes the impact of carbohydrates on energetic efficiency, partitioning of weight regain as fat and lean mass, and appetite control. Both the amount and frequency of postprandial glycemia add to body weight regulation after weight loss and strengthen the concept of glycemic index and glycemic load. In addition, dietary fiber and slowly or poorly absorbable functional sugars modify gastrointestinal peptides involved in appetite and metabolic regulation and exert prebiotic effects. Current evidence suggests that a low-glycemic load diet with a preference for low-glycemic index foods and integration of slowly digestible, poorly absorbable carbohydrates may improve weight-loss maintenance. Future studies should investigate the health benefits of low glycemic functional sweeteners (e.g., isomaltulose and tagatose).

Carbohydrate-Dependent, Exercise-Induced Gastrointestinal Distress

Directory of Open Access Journals (Sweden)

Erick Prado de Oliveira

2014-10-01

Full Text Available Gastrointestinal (GI problems are a common concern of athletes during intense exercise. Ultimately, these symptoms can impair performance and possibly prevent athletes from winning or even finishing a race. The main causes of GI problems during exercise are mechanical, ischemic and nutritional factors. Among the nutritional factors, a high intake of carbohydrate and hyperosmolar solutions increases GI problems. A number of nutritional manipulations have been proposed to minimize gastrointestinal symptoms, including the use of multiple transportable carbohydrates. This type of CHO intake increases the oxidation rates and can prevent the accumulation of carbohydrate in the intestine. Glucose (6% or glucose plus fructose (8%–10% beverages are recommended in order to increase CHO intake while avoiding the gastric emptying delay. Training the gut with high intake of CHO may increase absorption capacity and probably prevent GI distress. CHO mouth rinse may be a good strategy to enhance performance without using GI tract in exercises lasting less than an hour. Future strategies should be investigated comparing different CHO types, doses, and concentration in exercises with the same characteristics.

Carbohydrates as Fat Replacers.

Science.gov (United States)

Peng, Xingyun; Yao, Yuan

2017-02-28

The overconsumption of dietary fat contributes to various chronic diseases, which encourages attempts to develop and consume low-fat foods. Simple fat reduction causes quality losses that impede the acceptance of foods. Fat replacers are utilized to minimize the quality deterioration after fat reduction or removal to achieve low-calorie, low-fat claims. In this review, the forms of fats and their functions in contributing to food textural and sensory qualities are discussed in various food systems. The connections between fat reduction and quality loss are described in order to clarify the rationales of fat replacement. Carbohydrate fat replacers usually have low calorie density and provide gelling, thickening, stabilizing, and other texture-modifying properties. In this review, carbohydrates, including starches, maltodextrins, polydextrose, gums, and fibers, are discussed with regard to their interactions with other components in foods as well as their performances as fat replacers in various systems.

The effects of marine carbohydrates and glycosylated compounds on human health.

Science.gov (United States)

Kang, Hee-Kyoung; Seo, Chang Ho; Park, Yoonkyung

2015-03-16

Marine organisms have been recognized as a valuable source of bioactive compounds with industrial and nutraceutical potential. Recently, marine-derived carbohydrates, including polysaccharides and low molecular weight glycosylated oligosaccharides, have attracted much attention because of their numerous health benefits. Moreover, several studies have reported that marine carbohydrates exhibit various biological activities, including antioxidant, anti-infection, anticoagulant, anti-inflammatory, and anti-diabetic effects. The present review discusses the potential industrial applications of bioactive marine carbohydrates for health maintenance and disease prevention. Furthermore, the use of marine carbohydrates in food, cosmetics, agriculture, and environmental protection is discussed.

Carbohydrates-tailored phase tunable systems composed of ionic liquids and water

International Nuclear Information System (INIS)

Chen Yuhaun; Wang Yige; Cheng Qingyan; Liu Xiaoli; Zhang Suojiang

2009-01-01

Carbohydrates were found to have substantial effects on tailoring phase tunable of ionic liquids (ILs) and water. Phase behaviors of 1-alkyl-3-methylimidazolium derivatives [C n mim]X (n = 2 to 10, X = Cl - , Br - , BF 4 - )-carbohydrate-H 2 O were systemically investigated. For hydrophilic ILs, 1-alkyl-3-methylimidazolium tetrafluoroborate [C n mim]BF 4 (n = 3, 4), the homogeneous aqueous solution can be induced to separate two aqueous phases by addition of carbohydrate. For hydrophobic ILs, [C n mim]BF 4 (n = 5 to 10), the mutual solubility with water can be lowered by addition of carbohydrate. While 1-alkyl-3-methyl imidazolium chloride ([C n mim]Cl, n = 2 to 10) and 1-alkyl-3-methyl imidazolium bromide ([C n mim]Br, n = 2 to 10) aqueous solutions never form aqueous two-phase systems (ATPSs) with carbohydrate in the investigated temperatures ranging from (242.15 to 373.15) K. The high partitioning behavior of phenol in [C n mim]BF 4 (n = 3 to 10) (1) + carbohydrate (2) + H 2 O (3) shows that carbohydrate-tailored {IL + H 2 O} systems are feasible to be used as extraction systems, especially in biological and environmental engineering.

Effects of Carbohydrate Source on Genetic Competence in Streptococcus mutans.

Science.gov (United States)

Moye, Zachary D; Son, Minjun; Rosa-Alberty, Ariana E; Zeng, Lin; Ahn, Sang-Joon; Hagen, Stephen J; Burne, Robert A

2016-08-01

The capacity to internalize and catabolize carbohydrates is essential for dental caries pathogens to persist and cause disease. The expression of many virulence-related attributes by Streptococcus mutans, an organism strongly associated with human dental caries, is influenced by the peptide signaling pathways that control genetic competence. Here, we demonstrate a relationship between the efficiency of competence signaling and carbohydrate source. A significant increase in the activity of the promoters for comX, comS, and comYA after exposure to competence-stimulating peptide (CSP) was observed in cells growing on fructose, maltose, sucrose, or trehalose as the primary carbohydrate source, compared to cells growing on glucose. However, only cells grown in the presence of trehalose or sucrose displayed a significant increase in transformation frequency. Notably, even low concentrations of these carbohydrates in the presence of excess glucose could enhance the expression of comX, encoding a sigma factor needed for competence, and the effects on competence were dependent on the cognate sugar:phosphotransferase permease for each carbohydrate. Using green fluorescent protein (GFP) reporter fusions, we observed that growth in fructose or trehalose resulted in a greater proportion of the population activating expression of comX and comS, encoding the precursor of comX-inducing peptide (XIP), after addition of CSP, than growth in glucose. Thus, the source of carbohydrate significantly impacts the stochastic behaviors that regulate subpopulation responses to CSP, which can induce competence in S. mutans The signaling pathways that regulate development of genetic competence in Streptococcus mutans are intimately intertwined with the pathogenic potential of the organism, impacting biofilm formation, stress tolerance, and expression of known virulence determinants. Induction of the gene for the master regulator of competence, ComX, by competence-stimulating peptide (CSP

Effects of Carbohydrate Source on Genetic Competence in Streptococcus mutans

Science.gov (United States)

Moye, Zachary D.; Son, Minjun; Rosa-Alberty, Ariana E.; Zeng, Lin; Ahn, Sang-Joon

2016-01-01

ABSTRACT The capacity to internalize and catabolize carbohydrates is essential for dental caries pathogens to persist and cause disease. The expression of many virulence-related attributes by Streptococcus mutans, an organism strongly associated with human dental caries, is influenced by the peptide signaling pathways that control genetic competence. Here, we demonstrate a relationship between the efficiency of competence signaling and carbohydrate source. A significant increase in the activity of the promoters for comX, comS, and comYA after exposure to competence-stimulating peptide (CSP) was observed in cells growing on fructose, maltose, sucrose, or trehalose as the primary carbohydrate source, compared to cells growing on glucose. However, only cells grown in the presence of trehalose or sucrose displayed a significant increase in transformation frequency. Notably, even low concentrations of these carbohydrates in the presence of excess glucose could enhance the expression of comX, encoding a sigma factor needed for competence, and the effects on competence were dependent on the cognate sugar:phosphotransferase permease for each carbohydrate. Using green fluorescent protein (GFP) reporter fusions, we observed that growth in fructose or trehalose resulted in a greater proportion of the population activating expression of comX and comS, encoding the precursor of comX-inducing peptide (XIP), after addition of CSP, than growth in glucose. Thus, the source of carbohydrate significantly impacts the stochastic behaviors that regulate subpopulation responses to CSP, which can induce competence in S. mutans. IMPORTANCE The signaling pathways that regulate development of genetic competence in Streptococcus mutans are intimately intertwined with the pathogenic potential of the organism, impacting biofilm formation, stress tolerance, and expression of known virulence determinants. Induction of the gene for the master regulator of competence, ComX, by competence

Carbohydrate digestion in Lutzomyia longipalpis' larvae (Diptera - Psychodidae).

Science.gov (United States)

Vale, Vladimir F; Moreira, Bruno H; Moraes, Caroline S; Pereira, Marcos H; Genta, Fernando A; Gontijo, Nelder F

2012-10-01

Lutzomyia longipalpis is the principal species of phlebotomine incriminated as vector of Leishmania infantum, the etiological agent of visceral leishmaniasis in the Americas. Despite its importance as vector, almost nothing related to the larval biology, especially about its digestive system has been published. The objective of the present study was to obtain an overview of carbohydrate digestion by the larvae. Taking in account that phlebotomine larvae live in the soil rich in decaying materials and microorganisms we searched principally for enzymes capable to hydrolyze carbohydrates present in this kind of substrate. The principal carbohydrases encountered in the midgut were partially characterized. One of them is a α-amylase present in the anterior midgut. It is probably involved with the digestion of glycogen, the reserve carbohydrate of fungi. Two other especially active enzymes were present in the posterior midgut, a membrane bound α-glucosidase and a membrane bound trehalase. The first, complete the digestion of glycogen and the other probably acts in the digestion of trehalose, a carbohydrate usually encountered in microorganisms undergoing hydric stress. In a screening done with the use of p-nitrophenyl-derived substrates other less active enzymes were also observed in the midgut. A general view of carbohydrate digestion in L. longipalpis was presented. Our results indicate that soil microorganisms appear to be the main source of nutrients for the larvae. Copyright © 2012 Elsevier Ltd. All rights reserved.

Low-carbohydrate diet induces metabolic depression: a possible mechanism to conserve glycogen.

Science.gov (United States)

Winwood-Smith, Hugh S; Franklin, Craig E; White, Craig R

2017-10-01

Long-term studies have found that low-carbohydrate diets are more effective for weight loss than calorie-restricted diets in the short term but equally or only marginally more effective in the long term. Low-carbohydrate diets have been linked to reduced glycogen stores and increased feelings of fatigue. We propose that reduced physical activity in response to lowered glycogen explains the diminishing weight loss advantage of low-carbohydrate compared with low-calorie diets over longer time periods. We explored this possibility by feeding adult Drosophila melanogaster a standard or a low-carbohydrate diet for 9 days and measured changes in metabolic rate, glycogen stores, activity, and body mass. We hypothesized that a low-carbohydrate diet would cause a reduction in glycogen stores, which recover over time, a reduction in physical activity, and an increase in resting metabolic rate. The low-carbohydrate diet reduced glycogen stores, which recovered over time. Activity was unaffected by diet, but metabolic rate was reduced, in the low-carbohydrate group. We conclude that metabolic depression could explain the decreased effectiveness of low-carbohydrate diets over time and recommend further investigation of long-term metabolic effects of dietary interventions and a greater focus on physiological plasticity within the study of human nutrition. Copyright © 2017 the American Physiological Society.

Carbohydrates as T-cell antigens with implications in health and disease.

Science.gov (United States)

Sun, Lina; Middleton, Dustin R; Wantuch, Paeton L; Ozdilek, Ahmet; Avci, Fikri Y

2016-10-01

Glycosylation is arguably the most ubiquitous post-translational modification on proteins in microbial and mammalian cells. During the past few years, there has been intensive research demonstrating that carbohydrates, either in pure forms or in conjunction with proteins or lipids, evoke and modulate adaptive immune responses. We now know that carbohydrates can be directly recognized by T cells or participate in T-cell stimulation as components of T-cell epitopes. T-cell recognition of carbohydrate antigens takes place via their presentation by major histocompatibility complex pathways on antigen-presenting cells. In this review, we summarize studies on carbohydrates as T-cell antigens modulating adaptive immune responses. Through discussion of glycan-containing antigens, such as glycoproteins, glycolipids, zwitterionic polysaccharides and carbohydrate-based glycoconjugate vaccines, we will illustrate the key molecular and cellular interactions between carbohydrate antigens and T cells and the implications of these interactions in health and disease. © The Author 2016. Published by Oxford University Press. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

Carbohydrate Content in the GDM Diet: Two Views: View 2: Low-Carbohydrate Diets Should Remain the Initial Therapy for Gestational Diabetes

OpenAIRE

Mulla, Wadia R.

2016-01-01

IN BRIEF The appropriate dietary intervention for gestational diabetes mellitus (GDM) is not clear. Traditionally, a low-carbohydrate diet has been prescribed. Recently, there has been a movement to prescribe a diet higher in nutrient-dense carbohydrate as the initial treatment for GDM. At this time, there is insufficient outcome data to support this type of diet.

Metabolism of non-structural carbohydrates in ruminants

OpenAIRE

Cañizares, G. I L [UNESP; Rodrigues, L. [UNESP; Cañizares, M. C. [UNESP

2009-01-01

The carbohydrates provide 50 to 80% of the dry matter of grain and roughage and can be divided into structural (cellulose, hemicellulose) and non-structural (starch, pectin and sugars). The non-structural carbohydrates are primarily digested in the rumen and its dynamic process is a sequence for the supply of nutrients to the intestine. The quality and quantity of products resulting from ruminal fermentation are dependent on the type and activity of microorganisms in the rumen influenced by t...

Dietary advices on carbohydrate intake for pregnant women with type 1 diabetes

DEFF Research Database (Denmark)

Roskjær, Ann B; Andersen, Jens Rikardt; Ronneby, Helle

2015-01-01

of Medicine (IOM) is generally recommended. A low-glycaemic index diet is considered safe, and has shown, positive effects on the glycaemic control and pregnancy outcomes for both healthy women, those with type 2 diabetic and gestational diabetes (GDM). In general, carbohydrate counting does improve glycaemic...... control in type 1 diabetes. A moderately low carbohydrate diet with a carbohydrate content of 40% of the calories results in better glycaemic control and comparable obstetric outcomes in type 2 diabetes and GDM when compared to a diet with a higher carbohydrate content, and is regarded safe in diabetic...... carbohydrate counting can be recommended for pregnant women with type 1 diabetes....

Carbohydrate-enriched cyanobacterial biomass as feedstock for bio-methane production through anaerobic digestion

DEFF Research Database (Denmark)

Markou, Giorgos; Angelidaki, Irini; Georgakakis, Dimitris

2013-01-01

The anaerobic digestion performance using carbohydrate-enriched biomass of Arthrospira platensis was studied. The carbohydrate enrichment was achieved after the cultivation of A. platensis under phosphorus limitation conditions. Three biomass compositions (60%, 40% and 20% carbohydrates content......) were used. The overall observation as the biomass carbohydrates increased was that bio-methane yield increased. The highest bio-methane yield in bioreactors with 60% carbohydrates was 203±10ml CH4 gCODinfl-1, while the lowest bio-methane yield in bioreactors with 20% carbohydrates was 123±10ml CH4 g......CODinfl-1. The trend of increasing bio-methane yield as carbohydrates content of the biomass increased was observed almost in all three HRT (15, 20 and 30days) studied and after thermal pre-treatment. However, thermal pre-treatment did not improve the bio-methane yield. Ammonia concentration had an overall...

Digestible and indigestible carbohydrates: interactions with postprandial lipid metabolism.

Science.gov (United States)

Lairon, Denis; Play, Barbara; Jourdheuil-Rahmani, Dominique

2007-04-01

The balance between fats and carbohydrates in the human diet is still a matter of very active debate. Indeed, the processing of ordinary mixed meals involves complex processes within the lumen of the upper digestive tract for digestion, in the small intestine mucosa for absorption and resecretion, and in peripheral tissues and in the circulation for final handling. The purpose of this review is to focus on available knowledge on the interactions of digestible or indigestible carbohydrates with lipid and lipoprotein metabolism in the postprandial state. The observations made in humans after test meals are reported and interpreted in the light of recent findings on the cellular and molecular levels regarding possible interplays between carbohydrates and lipid moieties in some metabolic pathways. Digestible carbohydrates, especially readily digestible starches or fructose, have been shown to exacerbate and/or delay postprandial lipemia, whereas some fiber sources can lower it. While interactions between dietary fibers and the process of lipid digestion and absorption have been studied mainly in the last decades, recent studies have shown that dietary carbohydrate moieties (e.g., glucose) can stimulate the intestinal uptake of cholesterol and lipid resecretion. In addition to the well-known glucose/fructose transporters, a number of transport proteins have recently been involved in intestinal lipid processing, whose implications in such interactions are discussed. The potential importance of postprandial insulinemia in these processes is also evaluated in the light of recent findings. The interactions of carbohydrates and lipid moieties in the postprandial state may result from both acute and chronic effects, both at transcriptional and posttranscriptional levels.

The effect of carbohydrates on alpha-amylase activity measurements

NARCIS (Netherlands)

Baks, T.; Janssen, A.E.M.; Boom, R.M.

2006-01-01

The Ceralpha method can be used for ¿-amylase activity measurements during the hydrolysis of starch at high substrate concentrations (>40 wt.%). However, the results are affected by the carbohydrates present in the samples. The effect of carbohydrates on the Ceralpha ¿-amylase activity

PREPARATION OF CHEMICALLY WELL-DEFINED CARBOHYDRATE DENDRIMER CONJUGATES

DEFF Research Database (Denmark)

2004-01-01

A method for the synthesis of dendrimer conjugates having a well-defined chemical structure, comprising one or more carbohydrate moieties and one or more immunomodulating substances coupled to a dendrimer, is presented. First, the carbohydrate is bound to the dendrimer in a chemoselective manner...... conjugates and their use in vaccination, production of antibodies, high throughput screening, diagnostic assays and libraries....

Entirely Carbohydrate-Based Vaccines: An Emerging Field for Specific and Selective Immune Responses

Directory of Open Access Journals (Sweden)

Sharmeen Nishat

2016-05-01

Full Text Available Carbohydrates are regarded as promising targets for vaccine development against infectious disease because cell surface glycans on many infectious agents are attributed to playing an important role in pathogenesis. In addition, oncogenic transformation of normal cells, in many cases, is associated with aberrant glycosylation of the cell surface glycan generating tumor associated carbohydrate antigens (TACAs. Technological advances in glycobiology have added a new dimension to immunotherapy when considering carbohydrates as key targets in developing safe and effective vaccines to combat cancer, bacterial infections, viral infections, etc. Many consider effective vaccines induce T-cell dependent immunity with satisfactory levels of immunological memory that preclude recurrence. Unfortunately, carbohydrates alone are poorly immunogenic as they do not bind strongly to the MHCII complex and thus fail to elicit T-cell immunity. To increase immunogenicity, carbohydrates have been conjugated to carrier proteins, which sometimes can impede carbohydrate specific immunity as peptide-based immune responses can negate antibodies directed at the targeted carbohydrate antigens. To overcome many challenges in using carbohydrate-based vaccine design and development approaches targeting cancer and other diseases, zwitterionic polysaccharides (ZPSs, isolated from the capsule of commensal anaerobic bacteria, will be discussed as promising carriers of carbohydrate antigens to achieve desired immunological responses.

Physiochemical Characteristics and Molecular Structures for Digestible Carbohydrates of Silages.

Science.gov (United States)

Refat, Basim; Prates, Luciana L; Khan, Nazir A; Lei, Yaogeng; Christensen, David A; McKinnon, John J; Yu, Peiqiang

2017-10-18

The main objectives of this study were (1) to assess the magnitude of differences among new barley silage varieties (BS) selected for varying rates of in vitro neutral detergent fiber (NDF) digestibility (ivNDFD; Cowboy BS with higher ivNDFD, Copeland BS with intermediate ivNDFD, and Xena BS with lower ivNDFD) with regard to their carbohydrate (CHO) molecular makeup, CHO chemical fractions, and rumen degradability in dairy cows in comparison with a new corn silage hybrid (Pioneer 7213R) and (2) to quantify the strength and pattern of association between the molecular structures and digestibility of carbohydrates. The carbohydrate-related molecular structure spectral data was measured using advanced vibrational molecular spectroscopy (FT/IR). In comparison to BS, corn silage showed a significantly (P carbohydrates were significantly (P carbohydrate content of the silages. In conclusion, the univariate approach with only one-factor consideration (ivNDFD) might not be a satisfactory method for evaluating and ranking BS quality. FT/IR molecular spectroscopy can be used to evaluate silage quality rapidly, particularly the digestible fiber content.

Frankincense tapping reduces the carbohydrate storage of Boswellia trees

NARCIS (Netherlands)

Mengistu, T.; Sterck, F.J.; Fetene, M.; Bongers, F.

2013-01-01

Carbohydrates fixed by photosynthesis are stored in plant organs in the form of starch or sugars. Starch and sugars sum to the total non-structural carbohydrate pool (TNC) and may serve as intermediate pools between assimilation and utilization. We examined the impact of tapping on TNC

Co-occurrence of carbohydrate malabsorption and primary epiploic appendagitis

Science.gov (United States)

Schnedl, Wolfgang J; Kalmar, Peter; Mangge, Harald; Krause, Robert; Wallner-Liebmann, Sandra J

2015-01-01

Unspecific abdominal complaints including bloating and irregular bowel movements may be caused by carbohydrate malabsorption syndromes, e.g., lactose and fructose malabsorption. These symptoms were investigated with hydrogen (H2) breath tests and correlated to carbohydrate malabsorption. During performing these H2-breath tests the patient presented with an acute, localized, non-migratory pain in the left lower abdominal quadrant. Primary epiploic appendagitis is a rare cause of abdominal acute or subacute complaints and diagnosis of primary epiploic appendagitis (PEA) is made when computed tomography reveals a characteristic lesion. We report on a patient with co-occurrence of lactose and fructose malabsorption, which was treated successfully with a diet free of culprit carbohydrates, with PEA recovering without medication or surgical treatment within few days. Since the abdominal unspecific symptoms had been present for months, they appeared not to be correlated to the acute localized abdominal pain, therefore we speculate on a random co-occurrence of combined carbohydrate malabsorption and PEA. PMID:26401090

Carbohydrate intake and obesity

NARCIS (Netherlands)

van Dam, R M; Seidell, J C

2007-01-01

The prevalence of obesity has increased rapidly worldwide and the importance of considering the role of diet in the prevention and treatment of obesity is widely acknowledged. This paper reviews data on the effects of dietary carbohydrates on body fatness. Does the composition of the diet as related

Structural basis of carbohydrate recognition by lectin II from Ulex europaeus, a protein with a promiscuous carbohydrate-binding site.

Science.gov (United States)

Loris, R; De Greve, H; Dao-Thi, M H; Messens, J; Imberty, A; Wyns, L

2000-08-25

Protein-carbohydrate interactions are the language of choice for inter- cellular communication. The legume lectins form a large family of homologous proteins that exhibit a wide variety of carbohydrate specificities. The legume lectin family is therefore highly suitable as a model system to study the structural principles of protein-carbohydrate recognition. Until now, structural data are only available for two specificity families: Man/Glc and Gal/GalNAc. No structural data are available for any of the fucose or chitobiose specific lectins. The crystal structure of Ulex europaeus (UEA-II) is the first of a legume lectin belonging to the chitobiose specificity group. The complexes with N-acetylglucosamine, galactose and fucosylgalactose show a promiscuous primary binding site capable of accommodating both N-acetylglucos amine or galactose in the primary binding site. The hydrogen bonding network in these complexes can be considered suboptimal, in agreement with the low affinities of these sugars. In the complexes with chitobiose, lactose and fucosyllactose this suboptimal hydrogen bonding network is compensated by extensive hydrophobic interactions in a Glc/GlcNAc binding subsite. UEA-II thus forms the first example of a legume lectin with a promiscuous binding site and illustrates the importance of hydrophobic interactions in protein-carbohydrate complexes. Together with other known legume lectin crystal structures, it shows how different specificities can be grafted upon a conserved structural framework. Copyright 2000 Academic Press.

Fructose and Sucrose Intake Increase Exogenous Carbohydrate Oxidation during Exercise

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Trommelen, Jorn; Fuchs, Cas J.; Beelen, Milou; Lenaerts, Kaatje; Jeukendrup, Asker E.; Cermak, Naomi M.; van Loon, Luc J. C.

2017-01-01

Peak exogenous carbohydrate oxidation rates typically reach ~1 g·min−1 during exercise when ample glucose or glucose polymers are ingested. Fructose co-ingestion has been shown to further increase exogenous carbohydrate oxidation rates. The purpose of this study was to assess the impact of fructose co-ingestion provided either as a monosaccharide or as part of the disaccharide sucrose on exogenous carbohydrate oxidation rates during prolonged exercise in trained cyclists. Ten trained male cyclists (VO2peak: 65 ± 2 mL·kg−1·min−1) cycled on four different occasions for 180 min at 50% Wmax during which they consumed a carbohydrate solution providing 1.8 g·min−1 of glucose (GLU), 1.2 g·min−1 glucose + 0.6 g·min−1 fructose (GLU + FRU), 0.6 g·min−1 glucose + 1.2 g·min−1 sucrose (GLU + SUC), or water (WAT). Peak exogenous carbohydrate oxidation rates did not differ between GLU + FRU and GLU + SUC (1.40 ± 0.06 vs. 1.29 ± 0.07 g·min−1, respectively, p = 0.999), but were 46% ± 8% higher when compared to GLU (0.96 ± 0.06 g·min−1: p exogenous carbohydrate oxidation rates during the latter 120 min of exercise were 46% ± 8% higher in GLU + FRU or GLU + SUC compared with GLU (1.19 ± 0.12, 1.13 ± 0.21, and 0.82 ± 0.16 g·min−1, respectively, p exogenous carbohydrate oxidation rates during prolonged exercise in trained cyclists. PMID:28230742

APPROACHING CARBOHYDRATES AND ITS METABOLISM: AN EXPERIENCE FOR EDUCATIONAL GAMES

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Sandro Henrique Dias Ribeiro

2016-11-01

Full Text Available INTRODUCTION: The study of carbohydrates, its metabolism and many other fields of biochemistry are often understood by students as a junction of chemical structures and reactions of difficult compression. However, Biochemistry should no longer be seen as an abstruse field, but a way to know the human body and its components, including molecular, structural and functional aspects. Therefore, some alternatives are being evaluated in order to assist and improve the dissemination of knowledge among them highlights are the educational games. OBJECTIVES: The aim of this work is the production of two educational games able to include the contents of carbohydrates and its metabolism in higher education. MATERIALS AND METHODS: The educational games produced were made from available materials and low cost. The games were tested in courses of Biological Sciences and Biotechnology of the Federal University of Uberlândia and the response of the students towards the activities was analyzed. The application, had the presence of trained students to instruct on the activity and correcting. DISCUSSION AND RESULTS: "What is the Carbohydrate?" and "Mastering the metabolism" are two educational games covering the content of structure and function carbohydrates and basal metabolism, respectively. "What is the Carbohydrate?" consists in unravel amid several options the carbohydrate in the hands of the others players. For this, several questions with two possible answers, “yes” or “not”, are accepted each round, and if the player find difficulty in formulating questions, there are cards tips. “Mastering the metabolism” consists in a combination of cards that simulate pieces of a domino that must be mounted following the metabolic pathway of carbohydrates, and as the game progresses, the main points of regulation of the pathway will be accompanied by surprise questions. The games showed great acceptance by students. CONCLUSION: “What is the Carbohydrate

Pharmaceutical, cosmeceutical, and traditional applications of marine carbohydrates.

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Ahmed, Abdul Bakrudeen Ali; Adel, Mohaddeseh; Karimi, Pegah; Peidayesh, Mahvash

2014-01-01

Marine carbohydrates are most important organic molecules made by photosynthetic organisms. It is very essential for humankind: the role in being an energy source for the organism and they are considered as an important dissolve organic compound (DOC) in marine environment's sediments. Carbohydrates found in different marine environments in different concentrations. Polysaccharides of carbohydrates play an important role in various fields such as pharmaceutical, food production, cosmeceutical, and so on. Marine organisms are good resources of nutrients, and they are rich carbohydrate in sulfated polysaccharide. Seaweeds (marine microalgae) are used in different pharmaceutical industries, especially in pharmaceutical compound production. Seaweeds have a significant amount of sulfated polysaccharides, which are used in cosmeceutical industry, besides based on the biological applications. Since then, traditional people, cosmetics products, and pharmaceutical applications consider many types of seaweed as an important organism used in food process. Sulfated polysaccharides containing seaweed have potential uses in the blood coagulation system, antiviral activity, antioxidant activity, anticancer activity, immunomodulating activity, antilipidepic activity, etc. Some species of marine organisms are rich in polysaccharides such as sulfated galactans. Various polysaccharides such as agar and alginates, which are extracted from marine organisms, have several applications in food production and cosmeceutical industries. Due to their high health benefits, compound-derived extracts of marine polysaccharides have various applications and traditional people were using them since long time ago. In the future, much attention is supposed to be paid to unraveling the structural, compositional, and sequential properties of marine carbohydrate as well. © 2014 Elsevier Inc. All rights reserved.

Hearing Loss, Dizziness, and Carbohydrate Metabolism.

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Albernaz, Pedro L Mangabeira

2016-07-01

Metabolic activity of the inner ear is very intense, and makes it sensitive to changes in the body homeostasis. This study involves a group of patients with inner ear disorders related to carbohydrate metabolism disturbances, including hearing loss, tinnitus, dizziness, and episodes of vertigo. To describe the symptoms of metabolic inner ear disorders and the examinations required to establish diagnoses. These symptoms are often the first to allow for an early diagnosis of metabolic disorders and diabetes. Retrospective study of 376 patients with inner ear symptoms suggestive of disturbances of carbohydrate metabolism. The authors present patientś clinical symptoms and clinical evaluations, with emphasis on the glucose and insulin essays. Authors based their conclusions on otolaryngological findings, diagnostic procedures and treatment principles. They found that auditory and vestibular symptoms usually occur prior to other manifestations of metabolic changes, leading to an early diagnosis of hyperinsulinemia, intestinal sugar malabsorption or diabetes. Previously undiagnosed diabetes mellitus type II was found in 39 patients. The identification of carbohydrate metabolism disturbances is important not only to minimize the patients' clinical symptoms, but also to help maintain their general health.

Hearing Loss, Dizziness, and Carbohydrate Metabolism

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Albernaz, Pedro L. Mangabeira

2015-07-01

Full Text Available Introduction Metabolic activity of the inner ear is very intense, and makes it sensitive to changes in the body homeostasis. This study involves a group of patients with inner ear disorders related to carbohydrate metabolism disturbances, including hearing loss, tinnitus, dizziness, and episodes of vertigo. Objectives To describe the symptoms of metabolic inner ear disorders and the examinations required to establish diagnoses. These symptoms are often the first to allow for an early diagnosis of metabolic disorders and diabetes. Methods Retrospective study of 376 patients with inner ear symptoms suggestive of disturbances of carbohydrate metabolism. The authors present patientś clinical symptoms and clinical evaluations, with emphasis on the glucose and insulin essays. Results Authors based their conclusions on otolaryngological findings, diagnostic procedures and treatment principles. They found that auditory and vestibular symptoms usually occur prior to other manifestations of metabolic changes, leading to an early diagnosis of hyperinsulinemia, intestinal sugar malabsorption or diabetes. Previously undiagnosed diabetes mellitus type II was found in 39 patients. Conclusions The identification of carbohydrate metabolism disturbances is important not only to minimize the patients' clinical symptoms, but also to help maintain their general health.

Low-carbohydrate diets for the treatment of obesity and type 2 diabetes.

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Hall, Kevin D; Chung, Stephanie T

2018-04-18

Summarize the physiological effects of low-carbohydrate diets as they relate to weight loss, glycemic control, and metabolic health. Low-carbohydrate diets are at least as effective for weight loss as other diets, but claims about increased energy expenditure and preferential loss of body fat are unsubstantiated. Glycemic control and hyperinsulinemia are improved by low-carbohydrate diets, but insulin sensitivity and glucose-stimulated insulin secretion may be impaired, especially in the absence of weight loss. Fasting lipid parameters are generally improved, but such improvements may depend on the quality of dietary fat and the carbohydrates they replaced. Postprandial hyperlipemia is a potential concern given the high fat content typical of low-carbohydrate diets. Low-carbohydrate diets have several potential benefits for treatment of obesity and type 2 diabetes, but more research is required to better understand their long-term consequences as well as the variable effects on the endocrine control of glucose, lipids, and metabolism.

Comparative analysis of carbohydrate active enzymes in Clostridium termitidis CT1112 reveals complex carbohydrate degradation ability.

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Riffat I Munir

Full Text Available Clostridium termitidis strain CT1112 is an anaerobic, gram positive, mesophilic, cellulolytic bacillus isolated from the gut of the wood-feeding termite, Nasutitermes lujae. It produces biofuels such as hydrogen and ethanol from cellulose, cellobiose, xylan, xylose, glucose, and other sugars, and therefore could be used for biofuel production from biomass through consolidated bioprocessing. The first step in the production of biofuel from biomass by microorganisms is the hydrolysis of complex carbohydrates present in biomass. This is achieved through the presence of a repertoire of secreted or complexed carbohydrate active enzymes (CAZymes, sometimes organized in an extracellular organelle called cellulosome. To assess the ability and understand the mechanism of polysaccharide hydrolysis in C. termitidis, the recently sequenced strain CT1112 of C. termitidis was analyzed for both CAZymes and cellulosomal components, and compared to other cellulolytic bacteria. A total of 355 CAZyme sequences were identified in C. termitidis, significantly higher than other Clostridial species. Of these, high numbers of glycoside hydrolases (199 and carbohydrate binding modules (95 were identified. The presence of a variety of CAZymes involved with polysaccharide utilization/degradation ability suggests hydrolysis potential for a wide range of polysaccharides. In addition, dockerin-bearing enzymes, cohesion domains and a cellulosomal gene cluster were identified, indicating the presence of potential cellulosome assembly.

Effects of carbohydrate and caffeine ingestion on performance during a rugby union simulation protocol.

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Roberts, Simon P; Stokes, Keith A; Trewartha, Grant; Doyle, Jenny; Hogben, Patrick; Thompson, Dylan

2010-06-01

In this study, we investigated the effect of ingesting carbohydrate alone or with caffeine on performance of a rugby union-specific shuttle running protocol. On three occasions, at least one week apart in a counterbalanced trial order, eight male rugby union forwards ingested either placebo or carbohydrate (1.2 g x kg(-1) body mass x h(-1)) before and during a rugby union-specific protocol, with pre-exercise caffeine ingestion (4 mg x kg(-1)) before one of the carbohydrate trials (carbohydrate + caffeine). The intermittent exercise protocol included walking, jogging, and cruising at pre-determined intensities, simulated contact events, a sustained high-intensity test of speed and agility (Performance Test), and a 15-m sprint. Ratings of perceived exertion (RPE) were recorded every 5 min and a motor skills test was performed after each 21-min block. Performance Test times were not significantly different between trials but the likelihood of 2% improvements for carbohydrate + caffeine over placebo and carbohydrate were 98% and 44%, respectively. For carbohydrate + caffeine, 15-m sprints were faster than for placebo (P=0.05) and the motor skills test was performed faster in the carbohydrate + caffeine trial than the carbohydrate and placebo trials (P benefit to rugby performance following co-ingestion of carbohydrate and caffeine.

Evidence supporting oral sensitivity to complex carbohydrates independent of sweet taste sensitivity in humans.

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Julia Y Q Low

Full Text Available Compared to simple sugars, complex carbohydrates have been assumed invisible to taste. However, two recent studies proposed that there may be a perceivable taste quality elicited by complex carbohydrates independent of sweet taste. There is precedent with behavioural studies demonstrating that rats are very attracted to complex carbohydrates, and that complex carbohydrates are preferred to simple sugars at low concentrations. This suggests that rats may have independent taste sensors for simple sugars and complex carbohydrates. The aim of this paper is to investigate oral sensitivities of two different classes of complex carbohydrates (a soluble digestible and a soluble non-digestible complex carbohydrate, and to compare these to other caloric and non-nutritive sweeteners in addition to the prototypical tastes using two commonly used psychophysical measures. There were strong correlations between the detection thresholds and mean intensity ratings for complex carbohydrates (maltodextrin, oligofructose (r = 0.94, P 0.05. However, moderate correlations were observed between perceived intensities of complex carbohydrates and sweeteners (r = 0.48-0.61, P < 0.05. These data provide evidence that complex carbohydrates can be sensed in the oral cavity over a range of concentrations independent of sweet taste sensitivity at low concentrations, but with partial overlap with sweet taste intensity at higher concentrations.

21 CFR 172.866 - Synthetic glycerin produced by the hydrogenolysis of carbohydrates.

Science.gov (United States)

2010-04-01

... of carbohydrates. 172.866 Section 172.866 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF... produced by the hydrogenolysis of carbohydrates. Synthetic glycerin produced by the hydrogenolysis of carbohydrates may be safely used in food, subject to the provisions of this section: (a) It shall contain not in...

Modified carbohydrate-chitosan compounds, methods of making the same and methods of using the same

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Venditti, Richard A; Pawlak, Joel J; Salam, Abdus; El-Tahlawy, Khaled Fathy

2015-03-10

Compositions of matter are provided that include chitosan and a modified carbohydrate. The modified carbohydrate includes a carbohydrate component and a cross linking agent. The modified carbohydrate has increased carboxyl content as compared to an unmodified counterpart carbohydrate. A carboxyl group of the modified carbohydrate is covalently bonded with an amino group of chitosan. The compositions of matter provided herein may include cross linked starch citrate-chitosan and cross linked hemicellulose citrate-chitosan, including foams thereof. These compositions yield excellent absorbency and metal chelation properties. Methods of making cross linked modified carbohydrate-chitosan compounds are also provided.

Histo-blood group carbohydrates as facilitators for infection by Helicobacter pylori.

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Brandão de Mattos, Cinara Cássia; de Mattos, Luiz Carlos

2017-09-01

Helicobacter pylori infect millions of people around the world. It occupies a niche in the human gastrointestinal tract characterized by high expression of a repertoire of carbohydrates. ABO and Lewis histo-blood group systems are controlled by genes coding for functional glycosyltransferases which synthesize great diversity of related fucosylated carbohydrate in different tissues, including gastrointestinal mucosa, and exocrine secretions. The structural diversity of histo-blood group carbohydrates is highly complex and depends on epistatic interactions among gene-encoding glycosyltransferases. The histo-blood group glycosyltransferases act in the glycosylation of proteins and lipids in the human gastrointestinal tract allowing the expression of a variety of potential receptors in which H. pylori can adhere. These oligosaccharide molecules are part of the gastrointestinal repertoire of carbohydrates which act as potential receptors for microorganisms, including H. pylori. This Gram-negative bacillus is one of the main causes of the gastrointestinal diseases such as chronic active gastritis, peptic ulcer, and cancer of stomach. Previous reports showed that some H. pylori strains use carbohydrates as receptors to adhere to the gastric and duodenal mucosa. Since some histo-blood group carbohydrates are highly expressed in one but not in others histo-blood group phenotypes it has pointed out that quantitative differences among them influence the susceptibility to diseases caused by H. pylori. Additionally, some experiments using animal model are helping us to understand how this bacillus explore histo-blood group carbohydrates as potential receptors, offering possibility to explore new strategies of management of infection, disease treatment, and prevention. This text highlights the importance of structural diversity of ABO and Lewis histo-blood group carbohydrates as facilitators for H. pylori infection. Copyright © 2017 Elsevier B.V. All rights reserved.

Postprandial Glucose Surges after Extremely Low Carbohydrate Diet in Healthy Adults.

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Kanamori, Koji; Ihana-Sugiyama, Noriko; Yamamoto-Honda, Ritsuko; Nakamura, Tomoka; Sobe, Chie; Kamiya, Shigemi; Kishimoto, Miyako; Kajio, Hiroshi; Kawano, Kimiko; Noda, Mitsuhiko

2017-09-01

Carbohydrate-restricted diets are prevalent not only in obese people but also in the general population to maintain appropriate body weight. Here, we report that extreme carbohydrate restriction for one day affects the subsequent blood glucose levels in healthy adults. Ten subjects (median age 30.5 years, BMI 21.1 kg/m 2 , and HbA1c 5.5%), wearing with a continuous glucose monitoring device, were given isoenergetic test meals for 4 consecutive days. On day 1, day 2 (D2), and day 4 (D4), they consumed normal-carbohydrate (63-66% carbohydrate) diet, while on day 3, they took low-carbohydrate/high-fat (5% carbohydrate) diet. The daily energy intake was 2,200 kcal for males and 1,700 kcal for females. On D2 and D4, we calculated the mean 24-hr blood glucose level (MEAN/24h) and its standard deviation (SD/24h), the area under the curve (AUC) for glucose over 140 mg/dL within 4 hours after each meal (AUC/4h/140), the mean amplitude of the glycemic excursions (MAGE), the incremental AUC of 24-hr blood glucose level above the mean plus one standard deviation (iAUC/MEAN+SD). Indexes for glucose fluctuation on D4 were significantly greater than those on D2 (SD/24h; p = 0.009, MAGE; p = 0.013, AUC/4h/140 after breakfast and dinner; p = 0.006 and 0.005, and iAUC/MEAN+SD; p = 0.007). The value of MEAN/24h and AUC/4h/140 after lunch on D4 were greater than those on D2, but those differences were not statistically significant. In conclusion, consumption of low-carbohydrate/high-fat diet appears to cause higher postprandial blood glucose on subsequent normal-carbohydrate diet particularly after breakfast and dinner in healthy adults.

Facultative thermogenesis induced by carbohydrate

DEFF Research Database (Denmark)

Astrup, A; Bülow, J; Christensen, N J

1986-01-01

In addition to the obligatory thermogenesis due to processing and storage, carbohydrate ingestion is accompanied by a facultative thermogenesis mediated by catecholamines via beta-adrenoceptors. The anatomical origin of facultative thermogenesis has hitherto not been determined. The possible...

Transition metals in carbohydrate chemistry

DEFF Research Database (Denmark)

Madsen, Robert

1997-01-01

This review describes the application of transition metal mediated reactions in carbohydrate synthesis. The different metal mediated transformations are divided into reaction types and illustrated by various examples on monosaccharide derivatives. Carbon-carbon bond forming reactions are further ...

Terrestrial carbohydrates support freshwater zooplankton during phytoplankton deficiency.

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Taipale, Sami J; Galloway, Aaron W E; Aalto, Sanni L; Kahilainen, Kimmo K; Strandberg, Ursula; Kankaala, Paula

2016-08-11

Freshwater food webs can be partly supported by terrestrial primary production, often deriving from plant litter of surrounding catchment vegetation. Although consisting mainly of poorly bioavailable lignin, with low protein and lipid content, the carbohydrates from fallen tree leaves and shoreline vegetation may be utilized by aquatic consumers. Here we show that during phytoplankton deficiency, zooplankton (Daphnia magna) can benefit from terrestrial particulate organic matter by using terrestrial-origin carbohydrates for energy and sparing essential fatty acids and amino acids for somatic growth and reproduction. Assimilated terrestrial-origin fatty acids from shoreline reed particles exceeded available diet, indicating that Daphnia may convert a part of their dietary carbohydrates to saturated fatty acids. This conversion was not observed with birch leaf diets, which had lower carbohydrate content. Subsequent analysis of 21 boreal and subarctic lakes showed that diet of herbivorous zooplankton is mainly based on high-quality phytoplankton rich in essential polyunsaturated fatty acids. The proportion of low-quality diets (bacteria and terrestrial particulate organic matter) was <28% of the assimilated carbon. Taken collectively, the incorporation of terrestrial carbon into zooplankton was not directly related to the concentration of terrestrial organic matter in experiments or lakes, but rather to the low availability of phytoplankton.

Carbohydrates – Guidelines on Parenteral Nutrition, Chapter 5

Science.gov (United States)

Bolder, U.; Ebener, C.; Hauner, H.; Jauch, K. W.; Kreymann, G.; Ockenga, J.; Traeger, K.

2009-01-01

The main role of carbohydrates in the human body is to provide energy. Carbohydrates should always be infused with PN (parenteral nutrition) in combination with amino acids and lipid emulsions to improve nitrogen balance. Glucose should be provided as a standard carbohydrate for PN, whereas the use of xylite is not generally recommended. Fructose solutions should not be used for PN. Approximately 60% of non-protein energy should be supplied as glucose with an intake of 3.0–3.5 g/kg body weight/day (2.1–2.4 mg/kg body weight/min). In patients with a high risk of hyperglycaemia (critically ill, diabetes, sepsis, or steroid therapy) an lower initial carbohydrate infusion rate of 1–2 g/kg body weight/day is recommended to achieve normoglycaemia. One should aim at reaching a blood glucose level of 80–110 mg/dL, and at least a glucose level <145 mg/dL should be achieved to reduce morbidity and mortality. Hyperglycaemia may require addition of an insulin infusion or a reduction (2.0–3.0 g/kg body weight/day) or even a temporary interruption of glucose infusion. Close monitoring of blood glucose levels is highly important. PMID:20049080

Carbohydrates – Guidelines on Parenteral Nutrition, Chapter 5

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Working group for developing the guidelines for parenteral nutrition of The German Association for Nutritional Medicine

2009-11-01

Full Text Available The main role of carbohydrates in the human body is to provide energy. Carbohydrates should always be infused with PN (parenteral nutrition in combination with amino acids and lipid emulsions to improve nitrogen balance. Glucose should be provided as a standard carbohydrate for PN, whereas the use of xylite is not generally recommended. Fructose solutions should not be used for PN. Approximately 60% of non-protein energy should be supplied as glucose with an intake of 3.0–3.5 g/kg body weight/day (2.1–2.4 mg/kg body weight/min. In patients with a high risk of hyperglycaemia (critically ill, diabetes, sepsis, or steroid therapy an lower initial carbohydrate infusion rate of 1–2 g/kg body weight/day is recommended to achieve normoglycaemia. One should aim at reaching a blood glucose level of 80–110 mg/dL, and at least a glucose level <145 mg/dL should be achieved to reduce morbidity and mortality. Hyperglycaemia may require addition of an insulin infusion or a reduction (2.0–3.0 g/kg body weight/day or even a temporary interruption of glucose infusion. Close monitoring of blood glucose levels is highly important.

Carbohydrates in the waters of ponds of Ramanthuruthu Island, Cochin

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Sankaranarayanan, V.N.; Kumaran, S.; Balasubramanian, T.; Stephen, R.; Panampunnayil, S.U.

carbohydrate showed high variability and the concentration varied from 0.2 to 11 mg/l. High concentration of particulate carbohydrate observed during monsoon months is believed to be due to high phytoplankton population and also to the large amount of organic...

Effects of polymeric carbohydrates on growth and development

DEFF Research Database (Denmark)

Knudsen, Knud Erik Bach

, metabolized and net energy); available energy relative to protein is crucial for performance and carcass quality; second, the proportion of starch to NSP will influence rate and type of metabolites (glucose vs. SCFA) deriving from carbohydrate assimilation, and finally, type of starch (types A, B, and C......The main objective of the presentation is to provide insight into the role of polymeric carbohydrates in growth and development of pigs. Polymeric carbohydrates—starch and non-starch polysaccharides (NSP)—quantitatively represent the largest portion of the diets for pigs and are therefore...... at a slower and more constant rate and with SCFA being absorbed by passive diffusion. Type and levels of polymeric carbohydrates influence growth and development through different mechanisms; first, the proportion of starch to NSP plays an important role for the content of available energy (digestible...

The effect of carbohydrates and lipids on the radiation-induced aggregation of proteins

International Nuclear Information System (INIS)

Delincee, H.; Jakubick, V.

1977-01-01

Myoglobin, ovalbumin and serum albumin have been irradiated in aqueous solution in the presence of varying amounts of carbohydrates and lipids, simulating a model food. Gel chromatography revealed the induction of protein aggregates, the formation of which depended strongly on protein concentration. The addition of carbohydrates (trehalose, starch) greatly reduced the amount of radiation-induced aggregates, whereas the addition of lipids (sunflower oil) had practically no effect on aggregate formation. However, if both carbohydrates and lipids were added, the decrease in aggregation caused by the carbohydrate addition was counteracted by the addition of the lipid; as increasing amounts of lipid were added, the effect of carbohydrate addition became smaller. (author)

Physiological aspects of energy metabolism and gastrointestinal effects of carbohydrates.

Science.gov (United States)

Elia, M; Cummings, J H

2007-12-01

The energy values of carbohydrates continue to be debated. This is because of the use of different energy systems, for example, combustible, digestible, metabolizable, and so on. Furthermore, ingested macronutrients may not be fully available to tissues, and the tissues themselves may not be able fully to oxidize substrates made available to them. Therefore, for certain carbohydrates, the discrepancies between combustible energy (cEI), digestible energy (DE), metabolizable energy (ME) and net metabolizable energy (NME) may be considerable. Three food energy systems are in use in food tables and for food labelling in different world regions based on selective interpretation of the digestive physiology and metabolism of food carbohydrates. This is clearly unsatisfactory and confusing to the consumer. While it has been suggested that an enormous amount of work would have to be undertaken to change the current ME system into an NME system, the additional changes may not be as great as anticipated. In experimental work, carbohydrate is high in the macronutrient hierarchy of satiation. However, studies of eating behaviour indicate that it does not unconditionally depend on the oxidation of one nutrient, and argue against the operation of a simple carbohydrate oxidation or storage model of feeding behaviour to the exclusion of other macronutrients. The site, rate and extent of carbohydrate digestion in, and absorption from the gut are key to understanding the many roles of carbohydrate, although the concept of digestibility has different meanings. Within the nutrition community, the characteristic patterns of digestion that occur in the small (upper) vs large (lower) bowel are known to impact in contrasting ways on metabolism, while in the discussion of the energy value of foods, digestibility is defined as the proportion of combustible energy that is absorbed over the entire length of the gastrointestinal tract. Carbohydrates that reach the large bowel are fermented to

Training of carbohydrate estimation for people with diabetes using mobile augmented reality.

Science.gov (United States)

Domhardt, Michael; Tiefengrabner, Martin; Dinic, Radomir; Fötschl, Ulrike; Oostingh, Gertie J; Stütz, Thomas; Stechemesser, Lars; Weitgasser, Raimund; Ginzinger, Simon W

2015-05-01

Imprecise carbohydrate counting as a measure to guide the treatment of diabetes may be a source of errors resulting in problems in glycemic control. Exact measurements can be tedious, leading most patients to estimate their carbohydrate intake. In the presented pilot study a smartphone application (BE(AR)), that guides the estimation of the amounts of carbohydrates, was used by a group of diabetic patients. Eight adult patients with diabetes mellitus type 1 were recruited for the study. At the beginning of the study patients were introduced to BE(AR) in sessions lasting 45 minutes per patient. Patients redraw the real food in 3D on the smartphone screen. Based on a selected food type and the 3D form created using BE(AR) an estimation of carbohydrate content is calculated. Patients were supplied with the application on their personal smartphone or a loaner device and were instructed to use the application in real-world context during the study period. For evaluation purpose a test measuring carbohydrate estimation quality was designed and performed at the beginning and the end of the study. In 44% of the estimations performed at the end of the study the error reduced by at least 6 grams of carbohydrate. This improvement occurred albeit several problems with the usage of BE(AR) were reported. Despite user interaction problems in this group of patients the provided intervention resulted in a reduction in the absolute error of carbohydrate estimation. Intervention with smartphone applications to assist carbohydrate counting apparently results in more accurate estimations. © 2015 Diabetes Technology Society.

Seasonal carbohydrate storage and mobilization in bearing and non-bearing pistachio (Pistacia vera) trees.

Science.gov (United States)

Spann, Timothy M; Beede, Robert H; Dejong, Theodore M

2008-02-01

We analyzed annual carbohydrate storage and mobilization of bearing ("on") and non-bearing ("off") 'Kerman' pistachio (Pistacia vera L.) trees growing on three different rootstocks. On all rootstocks, carbohydrate storage in shoots and branches of "on" and "off" trees was lowest following the spring growth flush. In "off" trees, stored carbohydrates increased and remained high after the initial growth flush. In "on" trees, stem carbohydrates increased temporarily in early summer, but were mobilized in mid-season during kernel fill, and then increased again after nut harvest. During the dormant season, the only substantial differences in carbohydrate storage between previously "on" and "off" trees were found in the roots of the weakest rootstock. The annual carbohydrate storage and mobilization pattern in canopy branches of heavily cropped pistachio trees appeared to be driven by carbohydrate demands related to nut development and untempered by tree vigor. Mobilization of carbohydrates from current-season and 1- and 2-year-old stem wood of "on" trees during the primary period of kernel fill corresponded with the period of inflorescence bud abscission. Thus, the alternate bearing pattern associated with inflorescence bud abscission in 'Kerman' pistachio may be a function of mid-season mobilization of stored carbohydrates in current-season stems resulting in stimulation of inflorescence bud abscission.

High-throughput screening for gene libraries expressing carbohydrate hydrolase activity

NARCIS (Netherlands)

Leemhuis, Hans; Euverink, Gert-Jan W.; Dijkhuizen, Lubbert

2003-01-01

A simple and fast method is described allowing screening of large number of Escherichia coli clones (4000 per day) for the presence of functional or improved carbohydrate hydrolase enzymes. The procedure is relatively cheap and has the advantage that carbohydrate degrading activity can be directly

Phosphorous Nutritional Level, Carbohydrate Reserves and Flower Quality in Olives.

Directory of Open Access Journals (Sweden)

Ran Erel

Full Text Available The olive tree is generally characterized by relatively low final fruit set consequential to a significant rate of undeveloped pistils, pistil abortion, and flower and fruitlet abscission. These processes are acknowledged to be governed by competition for resources between the developing vegetative and reproductive organs. To study the role of phosphorus (P nutritional level on reproductive development, trees were grown under four levels of P for three years in large containers. Phosphorus nutritional level was positively related to rate of reproductive bud break, inflorescence weight, rate of hermaphrodite flowers, pistil weight, fruitlet persistence, fruit set and the consequential total number of fruits. The positive impact of P nutrition on the productivity parameters was not related to carbohydrate reserves or to carbohydrate transport to the developing inflorescence. Phosphorous deficient trees showed significant impairment of assimilation rate, and yet, carbohydrates were accumulated in inflorescences at levels comparable to or higher than trees receiving high P. In contrast to female reproductive organs, pollen viability was consistently higher in P deficient trees, possibly due to the enhanced carbohydrate availability. Overall, the positive effect of P on female reproductive development was found to be independent of the total carbohydrate availability. Hence, P is speculated to have a direct influence on reproductive processes.

Phosphorous Nutritional Level, Carbohydrate Reserves and Flower Quality in Olives.

Science.gov (United States)

Erel, Ran; Yermiyahu, Uri; Yasuor, Hagai; Cohen Chamus, Dan; Schwartz, Amnon; Ben-Gal, Alon; Dag, Arnon

2016-01-01

The olive tree is generally characterized by relatively low final fruit set consequential to a significant rate of undeveloped pistils, pistil abortion, and flower and fruitlet abscission. These processes are acknowledged to be governed by competition for resources between the developing vegetative and reproductive organs. To study the role of phosphorus (P) nutritional level on reproductive development, trees were grown under four levels of P for three years in large containers. Phosphorus nutritional level was positively related to rate of reproductive bud break, inflorescence weight, rate of hermaphrodite flowers, pistil weight, fruitlet persistence, fruit set and the consequential total number of fruits. The positive impact of P nutrition on the productivity parameters was not related to carbohydrate reserves or to carbohydrate transport to the developing inflorescence. Phosphorous deficient trees showed significant impairment of assimilation rate, and yet, carbohydrates were accumulated in inflorescences at levels comparable to or higher than trees receiving high P. In contrast to female reproductive organs, pollen viability was consistently higher in P deficient trees, possibly due to the enhanced carbohydrate availability. Overall, the positive effect of P on female reproductive development was found to be independent of the total carbohydrate availability. Hence, P is speculated to have a direct influence on reproductive processes.

A curve fitting approach to estimate the extent of fermentation of indigestible carbohydrates

NARCIS (Netherlands)

Wang, H.; Weening, D.; Jonkers, E.; Boer, T.; Stellaard, F.; Small, A. C.; Preston, T.; Vonk, R. J.; Priebe, M. G.

Background Information about the extent of carbohydrate digestion and fermentation is critical to our ability to explore the metabolic effects of carbohydrate fermentation in vivo. We used cooked (13)C-labelled barley kernels, which are rich in indigestible carbohydrates, to develop a method which

A curve fitting approach to estimate the extent of fermentation of indigestible carbohydrates

NARCIS (Netherlands)

Wang, H.; Weening, D.; Jonkers, E.; Boer, T.; Stellaard, F.; Small, A. C.; Preston, T.; Vonk, R. J.; Priebe, M. G.

2008-01-01

Background Information about the extent of carbohydrate digestion and fermentation is critical to our ability to explore the metabolic effects of carbohydrate fermentation in vivo. We used cooked (13)C-labelled barley kernels, which are rich in indigestible carbohydrates, to develop a method which

Carbohydrates, Sugar, and Your Child

Science.gov (United States)

... carbs are: simple carbohydrates (or simple sugars): including fructose, glucose, and lactose, which also are found in nutritious ... sugar, check the ingredients list for sugar, corn syrup, or other sweeteners, such as dextrose, fructose, honey, or molasses, to name just a few. ...

Carbohydrates of human immunodeficiency virus

DEFF Research Database (Denmark)

Hansen, J E

1992-01-01

Elucidation of the mechanism by which viral infection induces the appearance of carbohydrate neoantigens is highly important. Results from such studies could be expected to be significant for a general understanding of the regulation of glycosylation, and perhaps especially important for the unde...

Separation of carbohydrates using hydrophilic interaction liquid chromatography.

Science.gov (United States)

Fu, Qing; Liang, Tu; Li, Zhenyu; Xu, Xiaoyong; Ke, Yanxiong; Jin, Yu; Liang, Xinmiao

2013-09-20

A strategy was developed to rapidly evaluate chromatographic properties of hydrophilic interaction chromatography (HILIC) columns for separating carbohydrates. Seven HILIC columns (Silica, Diol, TSK Amide-80, XAmide, Click Maltose, Click β-CD, and Click TE-Cys columns) were evaluated by using three monosaccharide and seven disaccharides as probes. The influence of column temperature on the peak shape and tautomerization of carbohydrates, as well as column selectivity were investigated. The influence of surface charge property on the retention was also studied by using glucose, glucuronic acid, and glucosamine, which indicated that buffer salt concentration and pH value in mobile phase was necessary to control the ionic interactions between ionic carbohydrates and HILIC columns. According to evaluation results, the XAmide column was selected as an example to establish experimental schemes for separation of complex mixtures of oligosaccharide. Copyright © 2013 Elsevier Ltd. All rights reserved.

Accumulation of reserve carbohydrate by rumen protozoa and bacteria in competition for glucose.

Science.gov (United States)

Denton, Bethany L; Diese, Leanne E; Firkins, Jeffrey L; Hackmann, Timothy J

2015-03-01

The aim of this study was to determine if rumen protozoa could form large amounts of reserve carbohydrate compared to the amounts formed by bacteria when competing for glucose in batch cultures. We separated large protozoa and small bacteria from rumen fluid by filtration and centrifugation, recombined equal protein masses of each group into one mixture, and subsequently harvested (reseparated) these groups at intervals after glucose dosing. This method allowed us to monitor reserve carbohydrate accumulation of protozoa and bacteria individually. When mixtures were dosed with a moderate concentration of glucose (4.62 or 5 mM) (n = 2 each), protozoa accumulated large amounts of reserve carbohydrate; 58.7% (standard error of the mean [SEM], 2.2%) glucose carbon was recovered from protozoal reserve carbohydrate at time of peak reserve carbohydrate concentrations. Only 1.7% (SEM, 2.2%) was recovered in bacterial reserve carbohydrate, which was less than that for protozoa (P protozoa can sequester sugar away from bacteria by accumulating reserve carbohydrate, giving protozoa a competitive advantage and stabilizing fermentation in the rumen. Similar experiments could be used to investigate the importance of starch sequestration. Copyright © 2015, American Society for Microbiology. All Rights Reserved.

Digestion kinetics of carbohydrate fractions of citrus by-products

DEFF Research Database (Denmark)

Lashkari, Saman; Taghizadeh, Akbar

2015-01-01

The present experiment was carried out to determine the digestion kinetics of carbohydrate fractions of citrus by-products. Grapefruit pulp (GP), lemon pulp (LE), lime pulp (LI) and orange pulp (OP) were the test feed. Digestion kinetic of whole citrus by-products and neutral detergent fiber (NDF......) fraction and acid detergent fiber (ADF) fractions of citrus by-products were measured using the in vitro gas production technique. Fermentation kinetics of the neutral detergent soluble carbohydrates (NDSC) fraction and hemicelluloses were calculated using a curve subtraction. The fermentation rate...... of whole was the highest for the LE (p by-products lag time was longer for hemicellulose than other carbohydrate fractions. There was no significant difference among potential gas production (A) volumes of whole test feeds (p

Glucuronoyl esterase--novel carbohydrate esterase produced by Schizophyllum commune.

Science.gov (United States)

Spániková, Silvia; Biely, Peter

2006-08-21

The cellulolytic system of the wood-rotting fungus Schizophyllum commune contains an esterase that hydrolyzes methyl ester of 4-O-methyl-d-glucuronic acid. The enzyme, called glucuronoyl esterase, was purified to electrophoretic homogeneity from a cellulose-spent culture fluid. Its substrate specificity was examined on a number of substrates of other carbohydrate esterases such as acetylxylan esterase, feruloyl esterase and pectin methylesterase. The glucuronoyl esterase attacks exclusively the esters of MeGlcA. The methyl ester of free or glycosidically linked MeGlcA was not hydrolysed by other carbohydrate esterases. The results suggest that we have discovered a new type of carbohydrate esterase that might be involved in disruption of ester linkages connecting hemicellulose and lignin in plant cell walls.

Enhancement of amylase production by Aspergillus sp. using carbohydrates mixtures from triticale

Directory of Open Access Journals (Sweden)

Dojnov Biljana

2015-01-01

Full Text Available For the purpose of finding a suitable available inducer in combination with starvation, carbohydrate mixtures from triticale was used as inducers and compared with well-known amylase inducers in fungi. Carbohydrate mixtures from triticale induced production of amylase cocktail (α-amylase and glucoamylase in Aspergillus niger, unlike induction with well-known inducers which induce only glucoamylase, showed by zymogram and TLC analysis of carbohydrates mixtures before and after fermentations. Glucoamylase production by A. niger was highest in the presence of extract obtained after autohydrolysis of starch from triticale (95.88 U/mL. Carbohydrate mixtures from triticale induced production of α-amylase in A. oryzae. More α-amylase isoforms were detected upon using complex carbohydrate mixture, compared to induction with maltose or starch. The 48 h induction was the most efficient by using triticale extract (101.35 U/mL. Carbohydrates from triticale extracts can be used as very good cheap amylase inducers. Triticale, still not fully utilized, could be taken into consideration as the inducer in amylase production by Aspergillus sp, such a way it could be used as sole substrate in fermentation. [Projekat Ministarstva nauke Republike Srbije, br. 172048

Solubility of carbohydrates in heavy water.

Science.gov (United States)

Cardoso, Marcus V C; Carvalho, Larissa V C; Sabadini, Edvaldo

2012-05-15

The solubility of several mono-(glucose and xylose), di-(sucrose and maltose), tri-(raffinose) and cyclic (α-cyclodextrin) saccharides in H(2)O and in D(2)O were measured over a range of temperatures. The solution enthalpies for the different carbohydrates in the two solvents were determined using the vant' Hoff equation and the values in D(2)O are presented here for the first time. Our findings indicate that the replacement of H(2)O by D(2)O remarkably decreases the solubilities of the less soluble carbohydrates, such as maltose, raffinose and α-cyclodextrin. On the other hand, the more soluble saccharides, glucose, xylose, and sucrose, are practically insensitive to the H/D replacement in water. Copyright © 2012 Elsevier Ltd. All rights reserved.

Systematic review and meta-analysis of dietary carbohydrate restriction in patients with type 2 diabetes

DEFF Research Database (Denmark)

Snorgaard, Ole; Møller, Grith; Andersen, Henning K

2017-01-01

Objective: Nutrition therapy is an integral part of selfmanagement education in patients with type 2 diabetes. Carbohydrates with a low glycemic index are recommended, but the ideal amount of carbohydrate in the diet is unclear. We performed a meta-analysis comparing diets containing low...... to moderate amounts of carbohydrate (LCD) (energy percentage below 45%) to diets containing high amounts of carbohydrate (HCD) in subjects with type 2 diabetes. Research design and methods: We systematically reviewed Cochrane library databases, EMBASE, and MEDLINE in the period 2004–2014 for guidelines, meta...... to moderate carbohydrate diets have greater effect on glycemic control in type 2 diabetes compared with high-carbohydrate diets in the first year of intervention. The greater the carbohydrate restriction, the greater glucose lowering, a relationship that has not been demonstrated earlier. Apart from...

Compatible topologies and parameters for NMR structure determination of carbohydrates by simulated annealing.

Science.gov (United States)

Feng, Yingang

2017-01-01

The use of NMR methods to determine the three-dimensional structures of carbohydrates and glycoproteins is still challenging, in part because of the lack of standard protocols. In order to increase the convenience of structure determination, the topology and parameter files for carbohydrates in the program Crystallography & NMR System (CNS) were investigated and new files were developed to be compatible with the standard simulated annealing protocols for proteins and nucleic acids. Recalculating the published structures of protein-carbohydrate complexes and glycosylated proteins demonstrates that the results are comparable to the published structures which employed more complex procedures for structure calculation. Integrating the new carbohydrate parameters into the standard structure calculation protocol will facilitate three-dimensional structural study of carbohydrates and glycosylated proteins by NMR spectroscopy.

Randomized clinical trial comparing an oral carbohydrate beverage with placebo before laparoscopic cholecystectomy

DEFF Research Database (Denmark)

Bisgaard, T; Kristiansen, V B; Hjortsø, N C

2004-01-01

BACKGROUND: Preoperative oral carbohydrate can attenuate postoperative insulin resistance and catabolism, and may have the potential to improve postoperative recovery. There are no data from randomized studies on postoperative clinical outcome after specific surgical procedures. This study...... evaluated the clinical effects of a preoperative carbohydrate beverage in patients undergoing laparoscopic cholecystectomy. METHODS: Ninety-four patients undergoing laparoscopic cholecystectomy were included in a randomized clinical trial. Patients were randomized to receive 800 ml of an iso-osmolar 12.......5 per cent carbohydrate-rich beverage the evening before operation (100 g carbohydrate) and another 400 ml (50 g carbohydrate) 2 h before initiation of anaesthesia, or the same volume of a placebo beverage. The primary endpoint was general well-being the day after operation. Patients were evaluated from...

Epinephrine mediates facultative carbohydrate-induced thermogenesis in human skeletal muscle

DEFF Research Database (Denmark)

Astrup, A; Simonsen, L; Bülow, J

1989-01-01

The thermic effect of carbohydrate has a component mediated by the sympathoadrenal system but of unknown anatomical localization. We have studied the contribution of skeletal muscle to the thermic effect of a carbohydrate-rich natural meal (115 g of carbohydrate, approximately 80% of energy...... postprandially and coinciding with the peak in arterial epinephrine. The present study provides evidence of a facultative thermogenic component in skeletal muscle, mediated by epinephrine via beta 2-adrenoreceptors. However, it also points to a nonmuscle component mediated through beta 1-adrenoceptors...... by norepinephrine released from the sympathetic nervous system. Consequently, the sympathoadrenal system seems to play a physiological role in the daily energy balance....

Effects of a plant-based high-carbohydrate/high-fiber diet versus high-monounsaturated fat/low-carbohydrate diet on postprandial lipids in type 2 diabetic patients.

Science.gov (United States)

De Natale, Claudia; Annuzzi, Giovanni; Bozzetto, Lutgarda; Mazzarella, Raffaella; Costabile, Giuseppina; Ciano, Ornella; Riccardi, Gabriele; Rivellese, Angela A

2009-12-01

To search for a better dietary approach to treat postprandial lipid abnormalities and improve glucose control in type 2 diabetic patients. According to a randomized crossover design, 18 type 2 diabetic patients (aged 59 +/- 5 years; BMI 27 +/- 3 kg/m(2)) (means +/- SD) in satisfactory blood glucose control on diet or diet plus metformin followed a diet relatively rich in carbohydrates (52% total energy), rich in fiber (28 g/1,000 kcal), and with a low glycemic index (58%) (high-carbohydrate/high-fiber diet) or a diet relatively low in carbohydrate (45%) and rich in monounsaturated fat (23%) (low-carbohydrate/high-monounsaturated fat diet) for 4 weeks. Thereafter, they shifted to the other diet for 4 more weeks. At the end of each period, plasma glucose, insulin, lipids, and lipoprotein fractions (separated by discontinuous density gradient ultracentrifugation) were determined on blood samples taken at fasting and over 6 h after a test meal having a similar composition as the corresponding diet. In addition to a significant decrease in postprandial plasma glucose, insulin responses, and glycemic variability, the high-carbohydrate/high-fiber diet also significantly improved the primary end point, since it reduced the postprandial incremental areas under the curve (IAUCs) of triglyceride-rich lipoproteins, in particular, chylomicrons (cholesterol IAUC: 0.05 +/- 0.01 vs. 0.08 +/- 0.02 mmol/l per 6 h; triglycerides IAUC: 0.71 +/- 0.35 vs. 1.03 +/- 0.58 mmol/l per 6 h, P carbohydrate and fiber, essentially based on legumes, vegetables, fruits, and whole cereals, may be particularly useful for treating diabetic patients because of its multiple effects on different cardiovascular risk factors, including postprandial lipids abnormalities.

[Carbohydrates and mental performance--the role of glycemic index of food products].

Science.gov (United States)

Ciok, Janusz; Dolna, Agnieszka

2006-03-01

The role of carbohydrates in proper functioning of central nervous system measured by parameters of cognitive performance was described. The only source of energy for the brain is glucose, which stimulates the production and secretion of acetylocholine. Important are also enough high blood level of insulin and the level of insulin growth factor (IGF). Many studies had showed that breakfast intake improves the ability of concentration, reaction time, learning ability, mood and memory. Not sufficient amount of nutritional carbohydrates may in opposite be negative for the results of some tests measuring cognitive performance. The results of studies showing that the disturbances in utilization of carbohydrates, present in the patients with diabetes, increase the risk of abnormalities of cognitive performance. There is some evidence that the kind of ingested carbohydrates is important. Several studies suggest that the intake of carbohydrates characterized by low glycemic index (GI) may be favorable for some parameters of cognitive performance, because of prolonged time of stable glicaemia after food ingestion.

Carbohydrate composition of compost during composting and mycelium growth of Agaricus bisporus.

Science.gov (United States)

Jurak, Edita; Kabel, Mirjam A; Gruppen, Harry

2014-01-30

Changes of plant cell wall carbohydrate structures occurring during the process to make suitable compost for growth of Agaricus bisporus are unknown. In this paper, composition and carbohydrate structures in compost samples collected during composting and mycelium growth were analyzed. Furthermore, different extracts of compost samples were prepared with water, 1M and 4M alkali and analyzed. At the beginning of composting, 34% and after 16 days of mycelium growth 27% of dry matter was carbohydrates. Carbohydrate composition analysis showed that mainly cellulose and poorly substituted xylan chains with similar amounts and ratios of xylan building blocks were present in all phases studied. Nevertheless, xylan solubility increased 20% over the period of mycelium growth indicating partial degradation of xylan backbone. Apparently, degradation of carbohydrates occurred over the process studied by both bacteria and fungi, mainly having an effect on xylan-chain length and solubility. Copyright © 2013 Elsevier Ltd. All rights reserved.

Recognition properties of receptors consisting of imidazole and indole recognition units towards carbohydrates

Directory of Open Access Journals (Sweden)

Monika Mazik

2010-02-01

Full Text Available Compounds 4 and 5, including both 4(5-substituted imidazole or 3-substituted indole units as the entities used in nature, and 2-aminopyridine group as a heterocyclic analogue of the asparagine/glutamine primary amide side chain, were prepared and their binding properties towards carbohydrates were studied. The design of these receptors was inspired by the binding motifs observed in the crystal structures of protein–carbohydrate complexes. 1H NMR spectroscopic titrations in competitive and non-competitive media as well as binding studies in two-phase systems, such as dissolution of solid carbohydrates in apolar media, revealed both highly effective recognition of neutral carbohydrates and interesting binding preferences of these acyclic compounds. Compared to the previously described acyclic receptors, compounds 4 and 5 showed significantly increased binding affinity towards β-galactoside. Both receptors display high β- vs. α-anomer binding preferences in the recognition of glycosides. It has been shown that both hydrogen bonding and interactions of the carbohydrate CH units with the aromatic rings of the receptors contribute to the stabilization of the receptor–carbohydrate complexes. The molecular modeling calculations, synthesis and binding properties of 4 and 5 towards selected carbohydrates are described and compared with those of the previously described receptors.

Effect of gamma irradiation on total carbohydrate concentration of finger millet flour

International Nuclear Information System (INIS)

Lathika; Patil, Shrikant L.; Bhasker Shenoy, K.; Somashekarappa, H.M.

2015-01-01

Ragi or finger millet (Eleusine coracana L.) is one of the common millets in several regions of India. The effect of gamma irradiation, on ragi flour was investigated in the study. Ragi flour is procured from market. Flour samples of 50 gms were taken in triplicates in a polyethylene pouch, air sealed and subjected to gamma irradiation doses ranging from 0.25 to 10 kGy and stored in polyethylene bags and plastic containers for a period of 30 and 90 days. Within 24 hours of irradiation, the samples were tested for total carbohydrate concentration by phenol-sulphuric acid method. The same was repeated after 30 and 90 days of storage. The comparative study showed that, at 0 day, total carbohydrate concentration has decreased slightly when compared to the non-irradiated sample (0.024 mg/ml). The lowest concentration of carbohydrate is seen at 0.025 kGy (0.019mg/ml). The samples stored in polyethylene bag, after 30 days showed both increase (0.056 mg/ml at 0.025 kGy) and decrease (0.04 mg/ml at 10 kGy) in total carbohydrate concentration when compared to control (0.046 mg/ml). 90 days stored samples showed increase in carbohydrate concentration when compared to control (0.029 mg/ml). The highest carbohydrate concentration is seen in 1 kGy dose (0.037 mg/ml). The samples stored at container after 30 days showed both increase (0.045 mg/ml at 5 kGy) and decrease (0.034 mg/ml at 0.025 mg/ml) of carbohydrate concentration when compared to control (0.043 mg/ml). 90 days stored samples showed decrease in carbohydrate concentration when compared to control (0.034 mg/ml). The lowest concentration is seen at 5 kGy (0.022 mg/ml). (author)

The statolith compartment in Chara rhizoids contains carbohydrate and protein

Science.gov (United States)

Wang-Cahill, F.; Kiss, J. Z.

1995-01-01

In contrast to higher plants, the alga Chara has rhizoids with single membrane-bound compartments that function as statoliths in gravity perception. Previous work has demonstrated that these statoliths contain barium sulfate crystals. In this study, we show that statoliths in Chara rhizoids react with a Coomassie Brilliant Blue cytochemical stain for proteins. While statoliths did not react with silver methenamine carbohydrate cytochemistry, the monoclonal antibody CCRC-M2, which is against a carbohydrate (sycamore-maple rhamnogalacturonan I), labeled the statolith compartment. These results demonstrate that in addition to barium sulfate, statoliths in Chara rhizoids have an organic matrix that consists of protein and carbohydrate moieties. Since the statoliths were silver methenamine negative, the carbohydrate in this compartment could be a 3-linked polysaccharide. CCRC-M2 also labeled Golgi cisternae, Golgi-associated vesicles, apical vesicles, and cell walls in the rhizoids. The specificity of CCRC-M2 immunolabeling was verified by several control experiments, including the demonstration that labeling was abolished when the antibody was preabsorbed with its antigen. Since in this and a previous study (John Z. Kiss and L. Andrew Staehelin, American Journal of Botany 80: 273-282, 1993) antibodies against higher plant carbohydrates crossreacted with cell walls of Chara in a specific manner, Characean algae may be a useful model system in biochemical and molecular studies of cell walls.

NIRS determination of non-structural carbohydrates, water soluble carbohydrates and other nutritive quality traits in whole plant maize with wide range variability

OpenAIRE

L. Campo; A. B. Monteagudo; B. Salleres; P. Castro; J. Moreno-Gonzalez

2013-01-01

The aim of this work was to study the potential of near-infrared reflectance spectroscopy (NIRS) to predict non-structural carbohydrates (NSC), water soluble carbohydrates (WSC), in vitro organic dry matter digestibility (IVOMD), organic matter (OM), crude protein (CP), neutral detergent fiber (NDF), acid detergent fiber (ADF) and starch in samples of whole plant maize with a wide range of variability. The samples were analyzed in reflectance mode by a spectrophotometer FOSS NIRSystems 6500. ...

Neutral carbohydrate geochemistry of particulate material in the central equatorial Pacific

Science.gov (United States)

Hernes, Peter J.; Hedges, John I.; Peterson, Michael L.; Wakeham, Stuart G.; Lee, Cindy

Neutral carbohydrate compositions were determined for particulate samples from plankton net tows, shallow floating sediment traps, mid-depth and deep moored sediment traps, and sediment cores collected along a north-south transect in the central equatorial Pacific Ocean during the U.S. JGOFS EqPac program. Total neutral carbohydrate depth profiles and patterns along the transect follow essentially the same trends as bulk and organic carbon (OC) fluxes—attenuating with depth, high near the equator and decreasing poleward. OC-normalized total aldose (TCH 2,O) yields along the transect and with depth do not show any consitent patterns. Relative to a planktonic source, neutral carbohydrate compositions in sediment trap and sediment core samples reflect preferential loss of ribose and storage carbohydrates rich in glucose, and preferential preservation of structural carbohydrates rich in rhamnose, xylose, fucose, and mannose. There is also evidence for an intermediately labile component rich in galactose. It appears that compositional signatures of neutral carbohydrates in sediments are more dependent upon their planktonic source than on any particular diagenetic pathway. Relative to other types of organic matter, neutral carbohydrates are better preserved in calcareous oozes from 12°S to 5°N than in red clays at 9°N based on OC-normalized TCH 2O yields, due to either differing sources or sorption characteristics. Weight per cent glucose generally decreases with increased degradation of organic material in the central equatorial Pacific region. Based on weight per cent glucose, comparisons of samples between Survey I (El Niõn) and Survey II (non-El Niño) indicate that during Survey I, organic material in the epipelagic zone in the northern hemisphere may have undergone more degradation than organic material in the southern hemisphere.

Is carbohydrate mouth rinsing a novel approach to maintain exercise performance during Ramadan fasting?

Directory of Open Access Journals (Sweden)

Ahmad Munir Che Muhamed

2014-12-01

Full Text Available About a decade ago, carbohydrate mouth rinsing was shown to enhance endurance exercise performance. This improvement was more pronounced in a fasted compared to a fed state, suggesting that the ergogenic effect of carbohydrate mouth rinse is dependent on endogenous carbohydrate storage. Hence, indirectly highlights the potential use of carbohydrate mouth rinse as a potential strategy to mitigate the adverse effects of exercise during Ramadan fasting. To date, only one study has been carried out to explore the potential benefit of carbohydrate mouth rinse on exercise performance during Ramadan fasting. This single observation showed that a 10-km time trial performance was enhanced when performing mouth rinsing with either a carbohydrate or a placebo solution as compared with not performing mouth rinsing. While one study had acknowledged that the practice of mouth rinsing do have a positive effect on exercise performance during Ramadan fasting, future studies is warranted in order to have a better understanding on the underlying mechanisms associated with carbohydrate mouth rinsing during Ramadan fasting.

Characterisation of the carbohydrate components of Taenia solium metacestode glycoprotein antigens.

Science.gov (United States)

Restrepo, B I; Obregón-Henao, A; Mesa, M; Gil, D L; Ortiz, B L; Mejía, J S; Villota, G E; Sanzón, F; Teale, J M

2000-05-01

Human neurocysticercosis is caused by Taenia solium metacestodes. It usually affects the central nervous system of humans and can be confused with other brain pathologies. The Lens culinaris-binding glycoproteins from this parasite have been shown to be ideal targets for the development of a highly specific immunoassay for the diagnosis of neurocysticercosis. In the present study we characterised the carbohydrates associated with five antigenic glycoproteins of T. solium metacestodes in the range of 12-28 kilodaltons. Lectin-affinities and enzymatic deglycosylations suggested that each of the five antigens contain various glycoforms of asparagine-linked carbohydrates of the hybrid, complex and probably high mannose type. These carbohydrates accounted for at least 30-66% of the apparent molecular mass of the glycoconjugates. In contrast, there was no evidence for the presence of O-linked carbohydrates. Lectin affinity patterns suggested that the sugars are short and truncated in their biosynthetic route, and that some contain terminal galactose moieties. Elucidating the precise structure of the carbohydrates and establishing their role in antigenicity will be essential to design strategies to produce them in large and reproducible amounts for the development of improved immunoassays.

Changes in molecular characteristics of cereal carbohydrates after processing and digestion.

Science.gov (United States)

Kasprzak, Mirosław Marek; Lærke, Helle Nygaard; Knudsen, Knud Erik Bach

2012-12-10

Different extraction, purification and digestion methods were used to investigate the molecular properties of carbohydrates in arabinoxylan and β-glucan concentrates, dietary fiber (DF) rich breads and ileum content of bread fed pigs. The breads studied were: a low DF wheat bread (WF), whole meal rye bread (GR), rye bread with kernels (RK), wheat bread supplemented with wheat arabinoxylan concentrate (AX) and wheat bread supplemented with oat β-glucan concentrate (BG). The weight average molecular weight (M(w)) of extractable carbohydrates in β-glucan concentrate decreased eight-fold after inclusion in the BG bread when exposed to in vitro digestion, while the M(w) of purified extractable carbohydrates in AX bread was reduced two-fold, and remained almost unaffected until reaching the terminal ileum of pigs. Similarly, the M(w) of purified extractable carbohydrates in GR and RK bread was not significantly changed in the ileum. The AX bread resulted in the highest concentration of dissolved arabinoxylan in the ileum among all the breads that caused a substantial increased in ileal AX viscosity. Nevertheless, for none of the breads, the M(w) of extractable carbohydrates was related neither to the bread extract nor ileal viscosity.

Changes in Molecular Characteristics of Cereal Carbohydrates after Processing and Digestion

Science.gov (United States)

Kasprzak, Mirosław Marek; Lærke, Helle Nygaard; Knudsen, Knud Erik Bach

2012-01-01

Different extraction, purification and digestion methods were used to investigate the molecular properties of carbohydrates in arabinoxylan and β-glucan concentrates, dietary fiber (DF) rich breads and ileum content of bread fed pigs. The breads studied were: a low DF wheat bread (WF), whole meal rye bread (GR), rye bread with kernels (RK), wheat bread supplemented with wheat arabinoxylan concentrate (AX) and wheat bread supplemented with oat β-glucan concentrate (BG). The weight average molecular weight (Mw) of extractable carbohydrates in β-glucan concentrate decreased eight-fold after inclusion in the BG bread when exposed to in vitro digestion, while the Mw of purified extractable carbohydrates in AX bread was reduced two-fold, and remained almost unaffected until reaching the terminal ileum of pigs. Similarly, the Mw of purified extractable carbohydrates in GR and RK bread was not significantly changed in the ileum. The AX bread resulted in the highest concentration of dissolved arabinoxylan in the ileum among all the breads that caused a substantial increased in ileal AX viscosity. Nevertheless, for none of the breads, the Mw of extractable carbohydrates was related neither to the bread extract nor ileal viscosity. PMID:23222731

Preparation and biological evaluation of radiolabelled antibodies with selected carbohydrate modifications

International Nuclear Information System (INIS)

Qi, P.; Koganty, R.R.; Selvaraj, S.

1993-01-01

Two carbohydrates, N-acetylgalactosamine (GalNAc) and galactose-β-1,3-GalNAc have been attached to human IgG (hIgG) by a novel linking reagent, hexafluoroglutaric acid dimethyl ester. Fluorine-19 NMR signals were used for the determination of the conjugation ratio. A third carbohydrate, sialic acid, was conjugated via reductive amination and the conjugation ratio determined by a resorcinol assay. The biological behaviour of these radiodinated antibodies with carbohydrate modification in normal mice indicates an enhanced liver uptake at 15 min post-injection with an associated change in circulating blood levels occurs for the galactose-based hIgG preparations. However, no significant differences in the biodistribution were observed for the sialic acid conjugate. These studies confirm the potential of carbohydrate-antibody conjugation for modifying the behaviour of antibodies in immunoscintigraphy and radioimmunotherapy. (author)

Simple mucin-type carbohydrate antigens in pleomorphic adenomas

DEFF Research Database (Denmark)

Therkildsen, M H; Mandel, U; Christensen, M

1993-01-01

Simple mucin-type carbohydrate structures, T, Tn and sialosyl-Tn, are regarded as general markers of carcinomas in several epithelial tissues as a result of incomplete synthesis with precursor accumulation. The structures have a very limited distribution in normal tissues and secretions, including...... saliva and salivary glands. The expression of simple mucin-type carbohydrate structures and ABH(O) variants was studied in paraffin-embedded and frozen tissue sections from 37 pleomorphic adenomas with associated normal parotid tissue, using immunohistology and a panel of MAbs with well...

N-O linkage in carbohydrates and glycoconjugates.

Science.gov (United States)

Chen, N; Xie, J

2016-11-29

The importance of oligosaccharides and their conjugates in various biological and pathological processes has stimulated growing interest in the development of (neo)glycoconjugates. Thanks to its high nucleophilicity, hydroxylamine has been employed as a powerful chemoselective ligation tool. Great effort has been focused on carbohydrates bearing aminooxy or N-hydroxy amino groups for organic synthesis, glycobiology and drug discovery. This review provides an overview of N-O linked carbohydrates and glycoconjugates, focusing particularly on the synthetic methodologies and chemical and physicochemical properties as well as biological and medical applications of N-glycosyl and O-glycosyl hydroxylamines, N-hydroxy amino and O-amino sugar as well as sugar aminooxy acid derivatives.

Influence of carbohydrates on the interaction of procyanidin B3 with trypsin.

Science.gov (United States)

Gonçalves, Rui; Mateus, Nuno; De Freitas, Victor

2011-11-09

The biological properties of procyanidins, in particular their inhibition of digestive enzymes, have received much attention in the past few years. Dietary carbohydrates are an environmental factor that is known to affect the interaction of procyanidins with proteins. This work aimed at understanding the effect of ionic food carbohydrates (polygalacturonic acid, arabic gum, pectin, and xanthan gum) on the interaction between procyanidins and trypsin. Physical-chemical techniques such as saturation transfer difference-NMR (STD-NMR) spectroscopy, fluorescence quenching, and nephelometry were used to evaluate the interaction process. Using STD-NMR, it was possible to identify the binding of procyanidin B3 to trypsin. The tested carbohydrates prevented the association of procyanidin B3 and trypsin by a competition mechanism in which the ionic character of carbohydrates and their ability to encapsulate procyanidins seem crucial leading to a reduction in STD signal and light scattering and to a recovery of the proteins intrinsic fluorescence. On the basis of these results, it was possible to grade the carbohydrates in their aggregation inhibition ability: XG > PA > AG ≫ PC. These effects may be relevant since the coingestion of procyanidins and ionic carbohydrates are frequent and furthermore since these might negatively affect the antinutritional properties ascribed to procyanidins in the past.

Carbohydrate-active enzymes from the zygomycete fungus Rhizopus oryzae: a highly specialized approach to carbohydrate degradation depicted at genome level

Directory of Open Access Journals (Sweden)

Henrissat Bernard

2011-01-01

Full Text Available Abstract Background Rhizopus oryzae is a zygomycete filamentous fungus, well-known as a saprobe ubiquitous in soil and as a pathogenic/spoilage fungus, causing Rhizopus rot and mucomycoses. Results Carbohydrate Active enzyme (CAZy annotation of the R. oryzae identified, in contrast to other filamentous fungi, a low number of glycoside hydrolases (GHs and a high number of glycosyl transferases (GTs and carbohydrate esterases (CEs. A detailed analysis of CAZy families, supported by growth data, demonstrates highly specialized plant and fungal cell wall degrading abilities distinct from ascomycetes and basidiomycetes. The specific genomic and growth features for degradation of easily digestible plant cell wall mono- and polysaccharides (starch, galactomannan, unbranched pectin, hexose sugars, chitin, chitosan, β-1,3-glucan and fungal cell wall fractions suggest specific adaptations of R. oryzae to its environment. Conclusions CAZy analyses of the genome of the zygomycete fungus R. oryzae and comparison to ascomycetes and basidiomycete species revealed how evolution has shaped its genetic content with respect to carbohydrate degradation, after divergence from the Ascomycota and Basidiomycota.

CARBOHYDRATE MALABSORPTION SYNDROME IN CHILDREN WITH VIRAL GASTROENTERITIS

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E. R. Meskina

2015-01-01

Full Text Available Background: Enteric viruses (mainly rotaviruses are the most common cause of infectious diarrhea in infants. One  of the  pathophysiologic mechanisms in rotaviral gastroenteritis is the  reduction of the  surface  activity of enterocyte disaccharidases  and  osmotic  diarrhea. Aim: To determine the clinical significance of metabolic activity of intestinal microbiota in the formation of the osmotic component of viral diarrhea in children of various ages. Materials and methods: The study involved 139 children aged  from 1 month  to 14 years admitted to the hospital in the first 24 to 72 hours of moderate-degree  viral gastroenteritis.  Rotaviral infection was the most prevalent  (90%. Viral etiology was confirmed  by the  reaction  of indirect hemagglutination and multiplex real-time PCR (in feces. Total carbohydrate content in the feces was measured and fecal microflora was investigated by two methods: bacteriological and gas liquid chromatography with the determination of short-chain fatty acids. Results: The mean carbohydrate content in the feces of children below 1.5 years of age was higher than  that  in older children (p = 0.014. There was an inverse correlation between the concentration of rotaviral antigens  and carbohydrate   contents (r = -0,43, p < 0.05 and the production of acetic and propionic acids (R = -0,35, p < 0.01. The carbohydrate content in acute stage of the disease was linearly associated with time to normalization of the stool (r = +0,47, p < 0.01. Previous acute  respiratory or intestinal  infections within 2 months (odds ratio [OR], 14.10; 95% confidence interval [CI] 3.86–51.53, previous  hospitalizations  (OR = 14.17; 95% CI 2.74–74.32 and  past  history of intestinal dysfunction (OR 5.68; 95% CI 1.67–19.76 were predictive of severe  carbohydrate malabsorption in children below 1.5 years of age. Conclusion: The lack of microbiota functional activity (assessed by production of short

The effects of whey protein with or without carbohydrates on resistance training adaptations.

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Hulmi, Juha J; Laakso, Mia; Mero, Antti A; Häkkinen, Keijo; Ahtiainen, Juha P; Peltonen, Heikki

2015-01-01

Nutrition intake in the context of a resistance training (RT) bout may affect body composition and muscle strength. However, the individual and combined effects of whey protein and carbohydrates on long-term resistance training adaptations are poorly understood. A four-week preparatory RT period was conducted in previously untrained males to standardize the training background of the subjects. Thereafter, the subjects were randomized into three groups: 30 g of whey proteins (n = 22), isocaloric carbohydrates (maltodextrin, n = 21), or protein + carbohydrates (n = 25). Within these groups, the subjects were further randomized into two whole-body 12-week RT regimens aiming either for muscle hypertrophy and maximal strength or muscle strength, hypertrophy and power. The post-exercise drink was always ingested immediately after the exercise bout, 2-3 times per week depending on the training period. Body composition (by DXA), quadriceps femoris muscle cross-sectional area (by panoramic ultrasound), maximal strength (by dynamic and isometric leg press) and serum lipids as basic markers of cardiovascular health, were analysed before and after the intervention. Twelve-week RT led to increased fat-free mass, muscle size and strength independent of post-exercise nutrient intake (P carbohydrate group independent of the type of RT (P carbohydrate group (P carbohydrates or combination of proteins and carbohydrates did not have a major effect on muscle size or strength when ingested two to three times a week. However, whey proteins may increase abdominal fat loss and relative fat-free mass adaptations in response to resistance training when compared to fast-acting carbohydrates.

Carbohydrate availability of arroz caldo with lambda-carrageenan.

Science.gov (United States)

Dumelod, B D; Ramirez, R P; Tiangson, C L; Barrios, E B; Panlasigui, L N

1999-07-01

Total available carbohydrate (sugars and starches) and total dietary fiber (soluble and insoluble) make up the total carbohydrate content of a food. Soluble fiber decreases the availability of glucose by delaying its absorption in the proximal small intestine, thus reducing the postprandial glucose levels (Jenkins et al., 1978; Schneeman, 1987a). Carrageenan, a seaweed extract, is a good source of soluble fiber (Montaño et al., 1985). This study aimed to determine the effect of carrageenan incorporation into arroz caldo on carbohydrate availability by monitoring the postprandial blood glucose levels of normal subjects. Control and experimental arroz caldo samples were prepared and subjected to proximate analysis and feeding studies. The total dietary fiber (TDF) content of the experimental (2.03%) was about thrice that of the control (0.68%). Using randomized crossover design, preweighed 55 g available carbohydrate serving portions of control and experimental arroz caldo samples, with 3.45 and 14.84 g TDF, respectively, were fed to ten fasting normal subjects then their postprandial blood glucose levels were determined at 15, 30, 45, 60 and 90 min intervals. Results of the short-term in vivo study showed that the mean postprandial glycaemic responses of subjects after consuming the experimental sample were significantly lower than the levels after consuming the control at 15, 45, and 90 min (P arroz caldo than control (147.29 +/- 53.34). The hypoglycaemic effect of carrageenan may prove useful in the prevention and management of metabolic conditions such as diabetes.

DMPD: Sweet preferences of MGL: carbohydrate specificity and function. [Dynamic Macrophage Pathway CSML Database

Lifescience Database Archive (English)

Full Text Available 18249034 Sweet preferences of MGL: carbohydrate specificity and function. van Vliet....csml) Show Sweet preferences of MGL: carbohydrate specificity and function. PubmedID 18249034 Title Sweet p...references of MGL: carbohydrate specificity and function. Authors van Vliet SJ, S

Radiation degradation of carbohydrates and their biological activities for plants

International Nuclear Information System (INIS)

Kume, T.; Nagasawa, N.; Matsuhashi, S.

2000-01-01

Radiation effects on carbohydrates such as chitosan, sodium alginate, carrageenan, cellulose, pectin have been investigated to improve the biological activities. These carbohydrates were easily degraded by irradiation and induced various kinds of biological activities such as anti-bacterial activity, promotion of plant growth, suppression of heavy metal stress, phytoalexins induction. Pectic fragments obtained from degraded pectin induced the phytoalexins such as glyceollins in soybean and pisatin in pea. The irradiated chitosan shows the higher elicitor activity for pisatin than that of pectin. For the plant growth promotion, alginate derived from brown marine algae, chitosan and ligno-cellulosic extracts show a strong activity. Kappa and iota carrageenan derived from red marine algae can promote growth of rice and the highest effect was obtained with kappa irradiated at 100 kGy. Some radiation degraded carbohydrates suppressed the damage of heavy metals on plants. The effects of irradiated carbohydrates on transportation of heavy metals have been investigated by PETIS (Positron Emitting Tracer Imaging System) and autoradiography using 48 V and 62 Zn. (author)

A randomized pilot trial of a moderate carbohydrate diet compared to a very low carbohydrate diet in overweight or obese individuals with type 2 diabetes mellitus or prediabetes

OpenAIRE

Saslow, LR; Kim, S; Daubenmier, JJ; Moskowitz, JT; Phinney, SD; Goldman, V; Murphy, EJ; Cox, RM; Moran, P; Hecht, FM

2014-01-01

We compared the effects of two diets on glycated hemoglobin (HbA1c) and other health-related outcomes in overweight or obese adults with type 2 diabetes or prediabetes (HbA1c>6%). We randomized participants to either a medium carbohydrate, low fat, calorie-restricted, carbohydrate counting diet (MCCR) consistent with guidelines from the American Diabetes Association (n = 18) or a very low carbohydrate, high fat, non calorie-restricted diet whose goal was to induce nutritional ketosis (LCK, n ...

High fat, low carbohydrate diet limit fear and aggression in Göttingen minipigs

DEFF Research Database (Denmark)

Haagensen, Annika Maria Juul; Sørensen, Dorte Bratbo; Sandøe, Peter

2014-01-01

High fat, low carbohydrate diets have become popular, as short-term studies show that such diets are effective for reducing body weight, and lowering the risk of diabetes and cardiovascular disease. There is growing evidence from both humans and other animals that diet affects behaviour and intake...... of fat has been linked, positively and negatively, with traits such as exploration, social interaction, anxiety and fear. Animal models with high translational value can help provide relevant and important information in elucidating potential effects of high fat, low carbohydrate diets on human behaviour....... Twenty four young, male Göttingen minipigs were fed either a high fat/cholesterol, low carbohydrate diet or a low fat, high carbohydrate/sucrose diet in contrast to a standard low fat, high carbohydrate minipig diet. Spontaneous behaviour was observed through video recordings of home pens and test...

Diagnosing and Treating Intolerance to Carbohydrates in Children.

Science.gov (United States)

Berni Canani, Roberto; Pezzella, Vincenza; Amoroso, Antonio; Cozzolino, Tommaso; Di Scala, Carmen; Passariello, Annalisa

2016-03-10

Intolerance to carbohydrates is relatively common in childhood, but still poorly recognized and managed. Over recent years it has come to the forefront because of progresses in our knowledge on the mechanisms and treatment of these conditions. Children with intolerance to carbohydrates often present with unexplained signs and symptoms. Here, we examine the most up-to-date research on these intolerances, discuss controversies relating to the diagnostic approach, including the role of molecular analysis, and provide new insights into modern management in the pediatric age, including the most recent evidence for correct dietary treatment.

Sugar Lego: gene composition of bacterial carbohydrate metabolism genomic loci.

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Kaznadzey, Anna; Shelyakin, Pavel; Gelfand, Mikhail S

2017-11-25

Bacterial carbohydrate metabolism is extremely diverse, since carbohydrates serve as a major energy source and are involved in a variety of cellular processes. Bacterial genes belonging to same metabolic pathway are often co-localized in the chromosome, but it is not a strict rule. Gene co-localization in linked to co-evolution and co-regulation. This study focuses on a large-scale analysis of bacterial genomic loci related to the carbohydrate metabolism. We demonstrate that only 53% of 148,000 studied genes from over six hundred bacterial genomes are co-localized in bacterial genomes with other carbohydrate metabolism genes, which points to a significant role of singleton genes. Co-localized genes form cassettes, ranging in size from two to fifteen genes. Two major factors influencing the cassette-forming tendency are gene function and bacterial phylogeny. We have obtained a comprehensive picture of co-localization preferences of genes for nineteen major carbohydrate metabolism functional classes, over two hundred gene orthologous clusters, and thirty bacterial classes, and characterized the cassette variety in size and content among different species, highlighting a significant role of short cassettes. The preference towards co-localization of carbohydrate metabolism genes varies between 40 and 76% for bacterial taxa. Analysis of frequently co-localized genes yielded forty-five significant pairwise links between genes belonging to different functional classes. The number of such links per class range from zero to eight, demonstrating varying preferences of respective genes towards a specific chromosomal neighborhood. Genes from eleven functional classes tend to co-localize with genes from the same class, indicating an important role of clustering of genes with similar functions. At that, in most cases such co-localization does not originate from local duplication events. Overall, we describe a complex web formed by evolutionary relationships of bacterial

Nitrogen and phosphorus removal coupled with carbohydrate production by five microalgae cultures cultivated in biogas slurry.

Science.gov (United States)

Tan, Fen; Wang, Zhi; Zhouyang, Siyu; Li, Heng; Xie, Youping; Wang, Yuanpeng; Zheng, Yanmei; Li, Qingbiao

2016-12-01

In this study, five microalgae strains were cultured for their ability to survive in biogas slurry, remove nitrogen resources and accumulate carbohydrates. It was proved that five microalgae strains adapted in biogas slurry well without ammonia inhibition. Among them, Chlorella vulgaris ESP-6 showed the best performance on carbohydrate accumulation, giving the highest carbohydrate content of 61.5% in biogas slurry and the highest ammonia removal efficiency and rate of 96.3% and 91.7mg/L/d respectively in biogas slurry with phosphorus and magnesium added. Additionally, the absence of phosphorus and magnesium that can be adverse for biomass accumulation resulted in earlier timing of carbohydrate accumulation and magnesium was firstly recognized and proved as the influence factor for carbohydrate accumulation. Microalgae that cultured in biogas slurry accumulated more carbohydrate in cell, making biogas slurry more suitable medium for the improvement of carbohydrate content, thus can be regarded as a new strategy to accumulate carbohydrate. Copyright © 2016 Elsevier Ltd. All rights reserved.

Influence of carbohydrate supplementation on skill performance during a soccer match simulation.

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Russell, Mark; Benton, David; Kingsley, Michael

2012-07-01

This study investigated the influence of carbohydrate supplementation on skill performance throughout exercise that replicates soccer match-play. Experimentation was conducted in a randomised, double-blind and cross-over study design. After familiarization, 15 professional academy soccer players completed a soccer match simulation incorporating passing, dribbling and shooting on two separate occasions. Participants received a 6% carbohydrate-electrolyte solution (CHO) or electrolyte solution (PL). Precision, success rate, ball speed and an overall index (speed-precision-success; SPS) were determined for all skills. Blood samples were taken at rest, immediately before exercise, every 15 min during exercise (first half: 15, 30 and 45 min; second half: 60, 75 and 90 min), and 10 min into the half time (half-time). Carbohydrate supplementation influenced shooting (time×treatment interaction: pinteraction: pCarbohydrate supplementation attenuated decrements in shooting performance during simulated soccer match-play; however, further research is warranted to optimise carbohydrate supplementation regimes for high-intensity intermittent sports. Copyright © 2012 Sports Medicine Australia. Published by Elsevier Ltd. All rights reserved.

Family differences related to carbohydrate utilization in rainbow trout Oncorhynchus mykiss

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Rainbow trout utilize protein as an energy source much more efficiently than carbohydrates. Alternative diets utilizing plant material typically contain higher levels of carbohydrate than standard fish meal diets. The goal of this study was to determine if there are molecular and physiological diffe...

The effect of growth medium on B. anthracis Sterne spore carbohydrate content.

Science.gov (United States)

Colburn, Heather A; Wunschel, David S; Antolick, Kathryn C; Melville, Angela M; Valentine, Nancy B

2011-06-01

The expressed characteristics of biothreat agents may be impacted by variations in the culture environment, including growth medium formulation. The carbohydrate composition of B. anthracis spores has been well studied, particularly for the exosporium, which is the outermost spore structure. The carbohydrate composition of the exosporium has been demonstrated to be distinct from the vegetative form containing unique monosaccharides. We have investigated the carbohydrate composition of B. anthracis Sterne spores produced using four different medium types formulated with different sources of medium components. The amount of rhamnose, 3-O-methyl rhamnose and galactosamine was found to vary significantly between spores cultured using different medium formulations. The relative abundance of these monosaccharides compared to other monosaccharides such as mannosamine was also found to vary with medium type. Specific medium components were also found to impact the carbohydrate profile. Xylose has not been previously described in B. anthracis spores but was detected at low levels in two media. This may represent residual material from the brewery yeast extract used to formulate these two media. These results illustrate the utility of this method to capture the impact of growth medium on carbohydrate variation in spores. Detecting carbohydrate profiles in B. anthracis evidentiary material may provide useful forensic information on the growth medium used for sporulation. Copyright © 2011 Elsevier B.V. All rights reserved.

Carbohydrates for Soccer: A Focus on Skilled Actions and Half-Time Practices

Directory of Open Access Journals (Sweden)

Samuel P. Hills

2017-12-01

Full Text Available Carbohydrate consumption is synonymous with soccer performance due to the established effects on endogenous energy store preservation, and physical capacity maintenance. For performance-enhancement purposes, exogenous energy consumption (in the form of drinks, bars, gels and snacks is recommended on match-day; specifically, before and during match-play. Akin to the demands of soccer, limited opportunities exist to consume carbohydrates outside of scheduled breaks in competition, such as at half-time. The link between cognitive function and blood glucose availability suggests that carbohydrates may influence decision-making and technical proficiency (e.g., soccer skills. However, relatively few reviews have focused on technical, as opposed to physical, performance while also addressing the practicalities associated with carbohydrate consumption when limited in-play feeding opportunities exist. Transient physiological responses associated with reductions in activity prevalent in scheduled intra-match breaks (e.g., half-time likely have important consequences for practitioners aiming to optimize match-day performance. Accordingly, this review evaluated novel developments in soccer literature regarding (1 the ergogenic properties of carbohydrates for skill performance; and (2 novel considerations concerning exogenous energy provision during half-time. Recommendations are made to modify half-time practices in an aim to enhance subsequent performance. Viable future research opportunities exist regarding a deeper insight into carbohydrate provision on match-day.

The effects of carbohydrate ingestion on the badminton serve after fatiguing exercise.

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Bottoms, Lindsay; Sinclair, Jonathan; Taylor, Katrina; Polman, Remco; Fewtrell, David

2012-01-01

The badminton serve requires great skill and may be affected by fatigue. The aim of the present study was to determine whether carbohydrate ingestion affects badminton performance. Nine male badminton players (age 25 ± 7 years, mass 80.6 ± 8.0 kg) attended the laboratory on three occasions. The first visit involved an incremental exercise test to exhaustion to determine peak heart rate. Participants were given 1 L of a carbohydrate-electrolyte drink or a matched placebo during the experimental trials. The accuracy of 10 long and 10 short serves was determined before and after exercise. The fatiguing exercise was 33 min in duration (83 ± 10% and 84 ± 8% peak heart rate for the placebo and carbohydrate trial respectively). Capillary blood samples (20 μL) were taken before and after exercise for determination of blood glucose and lactate. There was deterioration in long serve accuracy with fatigue (P = 0.002), which carbohydrate ingestion had a tendency to prevent (P = 0.077). There was no effect of fatigue (P = 0.402) or carbohydrate ingestion (P = 0.109) on short serve accuracy. There was no difference in blood glucose concentration between trials (P = 0.851). Blood lactate concentration was higher during the placebo trial (P = 0.016). These results suggest that only the long serve is influenced by fatigue and carbohydrate had a tendency to prevent the deterioration in performance.

A convenient method for synthesis of glyconanoparticles for colorimetric measuring carbohydrate-protein interactions

International Nuclear Information System (INIS)

Chuang, Yen-Jun; Zhou, Xichun; Pan, Zhengwei; Turchi, Craig

2009-01-01

Carbohydrate functionalized nanoparticles, i.e., the glyconanoparticles, have wide application ranging from studies of carbohydrate-protein interactions, in vivo cell imaging, biolabeling, etc. Currently reported methods for preparation of glyconanoparticles require multi-step modifications of carbohydrates moieties to conjugate to nanoparticle surface. However, the required synthetic manipulations are difficult and time consuming. We report herewith a simple and versatile method for preparing glyconanoparticles. This method is based on the utilization of clean and convenient microwave irradiation energy for one-step, site-specific conjugation of unmodified carbohydrates onto hydrazide-functionalized Au nanoparticles. A colorimetric assay that utilizes the ensemble of gold glyconanoparticles and Concanavalin A (ConA) was also presented. This feasible assay system was developed to analyze multivalent interactions and to determine the dissociation constant (K d ) for five kind of Au glyconanoparticles with lectin. Surface plasmon changes of the Au glyconanoparticles as a function of lectin-carbohydrate interactions were measured and the dissociation constants were determined based on non-linear curve fitting. The strength of the interaction of carbohydrates with ConA was found to be as follows: maltose > mannose > glucose > lactose > MAN5.

Genetic and phenotypic analysis of carbohydrate metabolism and transport in Lactobacillus reuteri.

Science.gov (United States)

Zhao, Xin; Gänzle, Michael G

2018-05-02

Lactobacilli derive metabolic energy mainly from carbohydrate fermentation. Homofermentative and heterofermentative lactobacilli exhibit characteristic differences in carbohydrate transport and regulation of metabolism, however, enzymes for carbohydrate transport in heterofermentative lactobacilli are poorly characterized. This study aimed to identify carbohydrate active enzymes in the L. reuteri strains LTH2584, LTH5448, TMW1.656, TMW1.112, 100-23, mlc3, and lpuph by phenotypic analysis and comparative genomics. Sourdough and intestinal isolates of L. reuteri displayed no difference in the number and type of carbohydrate-active enzymes encoded in the genome. Predicted sugar transporters encoded by genomes of L. reuteri strains were secondary carriers and most belong to the major facilitator superfamily. The quantification of gene expression during growth in sourdough and in chemically defined media corresponded to the predicted function of the transporters MalT, ScrT and LacS as carriers for maltose, sucrose, and lactose or raffinose, respectively. The genotype for sugar utilization matched the fermentation profile of 39 sugars for L. reuteri strains, and indicated preference for maltose, sucrose, raffinose and (iso)-malto-oligosaccharides, which are available in sourdough and in the upper intestine of rodents. Pentose utilization in L. reuteri species was strain-specific but independent of the origin or phylogenetic position of isolates. Two glycosyl hydrolases, licheninase (EC 3.2.1.73) and endo-1, 4-β-galactosidase (EC 3.2.1.89) were identified based on conserved domains. In conclusion, the study identified the lack of PTS systems, preference for secondary carriers for carbohydrate transport, and absence of carbon catabolite repression as characteristic features of the carbohydrate metabolism in the heterofermentative L. reuteri. Copyright © 2018 Elsevier B.V. All rights reserved.

Fat and carbohydrate metabolism during submaximal exercise in children.

Science.gov (United States)

Aucouturier, Julien; Baker, Julien S; Duché, Pascale

2008-01-01

During exercise, the contribution of fat and carbohydrate to energy expenditure is largely modulated by the intensity of exercise. Age, a short- or long-term diet enriched in carbohydrate or fat substrate stores, training and gender are other factors that have also been found to affect this balance. These factors have been extensively studied in adults from the perspective of improving performance in athletes, or from a health perspective in people with diseases. During the last decade, lifestyle changes associated with high-energy diets rich in lipid and reduced physical activity have contributed to the increase in childhood obesity. This lifestyle change has emerged as a serious health problem favouring the early development of cardiovascular diseases, insulin resistance or type 2 diabetes mellitus. Increasing physical activity levels in young people is important to increase energy expenditure and promote muscle oxidative capacity. Therefore, it is surprising that the regulation of balance between carbohydrate and lipid use during exercise has received much less attention in children than in adults. In this review, we have focused on the factors that affect carbohydrate and lipid metabolism during exercise and have identified areas that may be relevant in explaining the higher contribution of lipid to energy expenditure in children when compared with adults. Low muscle glycogen content is possibly associated with a low activity of glycolytic enzymes and high oxidative capacity, while lower levels of sympathoadrenal hormones are likely to favour lipid metabolism in children. Changes in energetic metabolism occurring during adolescence are also dependent on pubertal events with an increase in testosterone in boys and estrogen and progesterone in girls. The profound effects of ovarian hormones on carbohydrate and fat metabolism along with their effects on oxidative enzymes could explain that differences in substrate metabolism have not always been observed between

Opposite regulation of insulin sensitivity by dietary lipid versus carbohydrate excess

DEFF Research Database (Denmark)

Lundsgaard, Annemarie; Sjøberg, Kim Anker; Høeg, Louise Dalgas

2017-01-01

To understand the mechanisms in lipid-induced insulin resistance, a more physiologic approach is to enhance FA availability through the diet. Nine healthy men ingested two hypercaloric diets (+75 E%) for three days, enriched in unsaturated FA (78 E% fat; UNSAT) or carbohydrates (80 E% carbohydrate...

Lanthanide-IMAC enrichment of carbohydrates and polyols.

Science.gov (United States)

Schemeth, Dieter; Rainer, Matthias; Messner, Christoph B; Rode, Bernd M; Bonn, Günther K

2014-03-01

In this study a new type of immobilized metal ion affinity chromatography resin for the enrichment of carbohydrates and polyols was synthesized by radical polymerization reaction of vinyl phosphonic acid and 1,4-butandiole dimethacrylate using azo-bis-isobutyronitrile as radical initiator. Interaction between the chelated trivalent lanthanide ions and negatively charged hydroxyl groups of carbohydrates and polyols was observed by applying high pH values. The new method was evaluated by single standard solutions, mixtures of standards, honey and a more complex extract of Cynara scolymus. The washing step was accomplished by acetonitrile in excess volumes. Elution of enriched carbohydrates was successfully performed with deionized water. The subsequent analysis was carried out with matrix-free laser desorption/ionization-time of flight mass spectrometry involving a TiO2 -coated steel target, especially suitable for the measurement of low-molecular-weight substances. Quantitative analysis of the sugar alcohol xylitol as well as the determination of the maximal loading capacity was performed by gas chromatography in conjunction with mass spectrometric detection after chemical derivatization. In a parallel approach quantum mechanical geometry optimizations were performed in order to compare the coordination behavior of various trivalent lanthanide ions. Copyright © 2013 John Wiley & Sons, Ltd.

IRMPD Spectroscopy Sheds New (Infrared) Light on the Sulfate Pattern of Carbohydrates.

Science.gov (United States)

Schindler, B; Barnes, L; Gray, C J; Chambert, S; Flitsch, S L; Oomens, J; Daniel, R; Allouche, A R; Compagnon, I

2017-03-16

IR spectroscopy of gas-phase ions is proposed to resolve positional isomers of sulfated carbohydrates. Mass spectrometric fingerprints and gas-phase vibrational spectra in the near and mid-IR regions were obtained for sulfated monosaccharides, yielding unambiguous signatures of sulfated isomers. We report the first systematic exploration of the biologically relevant but notoriously challenging deprotonated state in the near IR region. Remarkably, anions displayed very atypical vibrational profiles, which challenge the well-established DFT (Density Functionnal Theory) modeling. The proposed approach was used to elucidate the sulfate patterns in glycosaminoglycans, a ubiquitous class of mammalian carbohydrates, which is regarded as a major challenge in carbohydrate structural analysis. Isomeric glycosaminoglycan disaccharides from heparin and chondroitin sources were resolved, highlighting the potential of infrared multiple photon dissociation spectroscopy as a novel structural tool for carbohydrates.

Issues in Nutrition: Carbohydrates.

Science.gov (United States)

Thompson, Margaret E; Noel, Mary Barth

2017-01-01

Carbohydrates include sugars, starches, and dietary fibers. Resistant starches resemble fiber in their behavior in the intestinal tract, and may have positive effects on blood glucose levels and the gut microbiome. Fibers are classified as soluble and insoluble, but most fiber-containing foods contain a mixture of soluble and insoluble fiber. Soluble fiber has been shown to lower low-density lipoprotein cholesterol levels. Many artificial sweeteners and other sugar substitutes are available. Most natural sources of sweeteners also are energy sources. Many artificial sweeteners contain no kilocalories in the amounts typically used. Sugar alcohols may have a laxative effect when consumed in large amounts. Glycemic index and glycemic load are measurements that help quantify serum glucose response after ingestion of particular foods. These measurements may be affected by the combination of foods consumed in a given meal, and the glycemic index may vary among individuals eating the same meal. Eating foods with a low glycemic index may help prevent development of type 2 diabetes. There is no definitive evidence to recommend low-carbohydrate diets over low-fat diets for long-term weight loss; they are equally effective. Written permission from the American Academy of Family Physicians is required for reproduction of this material in whole or in part in any form or medium.

High fat, low carbohydrate diet limit fear and aggression in Göttingen minipigs.

Directory of Open Access Journals (Sweden)

Annika Maria Juul Haagensen

Full Text Available High fat, low carbohydrate diets have become popular, as short-term studies show that such diets are effective for reducing body weight, and lowering the risk of diabetes and cardiovascular disease. There is growing evidence from both humans and other animals that diet affects behaviour and intake of fat has been linked, positively and negatively, with traits such as exploration, social interaction, anxiety and fear. Animal models with high translational value can help provide relevant and important information in elucidating potential effects of high fat, low carbohydrate diets on human behaviour. Twenty four young, male Göttingen minipigs were fed either a high fat/cholesterol, low carbohydrate diet or a low fat, high carbohydrate/sucrose diet in contrast to a standard low fat, high carbohydrate minipig diet. Spontaneous behaviour was observed through video recordings of home pens and test-related behaviours were recorded during tests involving animal-human contact and reaction towards a novel object. We showed that the minipigs fed a high fat/cholesterol, low carbohydrate diet were less aggressive, showed more non-agonistic social contact and had fewer and less severe skin lesions and were less fearful of a novel object than minipigs fed low fat, high carbohydrate diets. These results found in a porcine model could have important implications for general health and wellbeing of humans and show the potential for using dietary manipulations to reduce aggression in human society.

Significant suppression of myocardial (18)F-fluorodeoxyglucose uptake using 24-h carbohydrate restriction and a low-carbohydrate, high-fat diet.

Science.gov (United States)

Kobayashi, Yasuhiro; Kumita, Shin-ichiro; Fukushima, Yoshimitsu; Ishihara, Keiichi; Suda, Masaya; Sakurai, Minoru

2013-11-01

(18)F-fluorodeoxyglucose (FDG) positron emission tomography (PET)/computed tomography (CT) is a useful tool for evaluating inflammation. Because, myocardial-FDG uptake occurs with diverse physiology, it should be suppressed during evaluation of myocardial inflammation by FDG-PET/CT. Diets inducing fat-based metabolism, such as a low-carbohydrate, high-fat diet (LCHF), are used in uptake-suppression protocols. However, a complete suppression of myocardial-FDG uptake has not been established. Hence, we assessed the efficacy of 24-h carbohydrate restriction along with an LCHF diet compared to that of the conventional protocol in suppressing myocardial-FDG uptake and also compared fat and glucose metabolism between these protocols. Fourteen healthy volunteers agreed to undergo >24-h carbohydrate restriction (glucose, vs. 2.98 [1.76-6.43], p=0.001). Target-to-background ratios [myocardium-to-blood ratio (MBR), myocardium-to-lung ratio (MLR), and myocardium-to-liver ratio (MLvR)] were also significantly lower with the diet-preparation protocol [MBR: 0.75 (0.68-0.84) vs. 1.63 (0.98-4.09), pvs. 4.54 (2.53-12.78), p=0.004; MLvR: 0.48 (0.44-0.56) vs. 1.11 (0.63-2.32), p=0.002]. Only insulin levels were significantly different between the subjects in each protocol group (11.3 [6.2-15.1] vs. 3.9 [2.9-6.2]). Carbohydrate restriction together with an LCHF supplement administered 1h before FDG significantly suppressed myocardial-FDG uptake. FFAs and insulin might not directly affect myocardial-FDG uptake. Copyright © 2013 Japanese College of Cardiology. Published by Elsevier Ltd. All rights reserved.

Post-Gastric Bypass Hyperinsulinemic Hypoglycemia: Fructose is a Carbohydrate Which Can Be Safely Consumed.

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Bantle, Anne E; Wang, Qi; Bantle, John P

2015-08-01

Postprandial hypoglycemia after gastric bypass surgery is a serious problem. Available treatments are often ineffective. The objective was to test the hypotheses that injection of rapid-acting insulin before a high-carbohydrate meal or replacement of other carbohydrates with fructose in the meal would prevent hypoglycemia. This was a randomized, crossover trial comparing a high-carbohydrate meal with premeal saline injection (control), a high-carbohydrate meal with premeal insulin injection, and a high-fructose meal with total carbohydrate content similar to the control meal. The setting was an academic medical center. Ten patients with post-gastric bypass hyperinsulinemic hypoglycemia participated. Interventions included lispro insulin injected before test meals and replacement of other carbohydrates with fructose in test meals. The main outcome measure was plasma glucose meals. After the control meal, mean peak glucose and insulin were 173 ± 47 mg/dL and 134 ± 55 mU/L, respectively; mean glucose nadir was 44 ± 15 mg/dL; and eight of 10 subjects demonstrated glucose meal, mean peak postprandial glucose and insulin were 117 ± 20 mg/dL and 45 ± 31 mU/L, respectively (both P meal sweetened with fructose with little risk of hypoglycemia. Treatment with rapid-acting insulin before a carbohydrate-containing meal did not prevent hypoglycemia.

Prepregnancy low-carbohydrate dietary pattern and risk of gestational diabetes mellitus: a prospective cohort study

DEFF Research Database (Denmark)

Bao, Wei; Bowers, Katherine; Tobias, Deirdre K

2014-01-01

; an animal LCD score on the basis of intakes of carbohydrate, animal protein, and animal fat; and a vegetable LCD score on the basis of intakes of carbohydrate, vegetable protein, and vegetable fat. A higher score reflected a higher intake of fat and protein and a lower intake of carbohydrate...... protein and fat from vegetable food sources is not associated with the risk. Women of reproductive age who follow a low-carbohydrate dietary pattern may consider consuming vegetable rather than animal sources of protein and fat to minimize their risk of GDM.......-carbohydrate dietary patterns with risk of GDM. DESIGN: We included 21,411 singleton pregnancies in the Nurses' Health Study II. Prepregnancy LCD scores were calculated from validated food-frequency questionnaires, including an overall LCD score on the basis of intakes of carbohydrate, total protein, and total fat...

Interactions of polyphenols with carbohydrates, lipids and proteins.

Science.gov (United States)

Jakobek, Lidija

2015-05-15

Polyphenols are secondary metabolites in plants, investigated intensively because of their potential positive effects on human health. Their bioavailability and mechanism of positive effects have been studied, in vitro and in vivo. Lately, a high number of studies takes into account the interactions of polyphenols with compounds present in foods, like carbohydrates, proteins or lipids, because these food constituents can have significant effects on the activity of phenolic compounds. This paper reviews the interactions between phenolic compounds and lipids, carbohydrates and proteins and their impact on polyphenol activity. Copyright © 2014 Elsevier Ltd. All rights reserved.

Diagnosing and Treating Intolerance to Carbohydrates in Children

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Roberto Berni Canani

2016-03-01

Full Text Available Intolerance to carbohydrates is relatively common in childhood, but still poorly recognized and managed. Over recent years it has come to the forefront because of progresses in our knowledge on the mechanisms and treatment of these conditions. Children with intolerance to carbohydrates often present with unexplained signs and symptoms. Here, we examine the most up-to-date research on these intolerances, discuss controversies relating to the diagnostic approach, including the role of molecular analysis, and provide new insights into modern management in the pediatric age, including the most recent evidence for correct dietary treatment.

Cell wall carbohydrates content of pathogenic Candida albicans strain morphological forms.

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Staniszewska, Monika; Bondaryk, Małgorzata; Rabczenko, Daniel; Smoleńska-Sym, Gabriela; Kurzatkowski, Wiesław

2013-01-01

The study evaluated the cell wall carbohydrates fraction in blastoconidia grown in YEPD medium at 30 degrees C and in the conglomerate of true hyphae grown in human serum at 37 degrees C. The clinical isolate obtained from a child with widespread C. albicans infection was used in the study. The cells were broken with glass beads, centrifuged to harvest the cell wall followed by subjection to TFA hydrolysis and in the result of that released monosaccharides were detected by HPAEC-PAD. Both, serum and temperature conditions (37 degrees C) affected germination process influencing the cell wall carbohydrates content when incubation in serum was prolonged from 1 to 18 h. The mannan content of blastoconidia was almost twofold higher compared to filamentous forms (149.25 +/- 299.24 vs 77.26 +/- 122.07). The glucan content was threefold lower in blastoconidia compared to hyphae (251.86 +/- 243.44 vs 755.81 +/- 1299.30). The chitin level was fourfold lower in blastoconidia compared to filaments (23.86 +/- 54.09 vs 106.29 +/- 170.12). The reason for the differences in the carbohydrates content may be related to type of morphology induced in different environmental conditions. Among tested carbohydrates, glucan appeared to be present in appreciably larger amounts in both tested morphological fractions. The ultrastructure of the blastoconidial cell wall revealed striking differences compared to the hyphae indicating the carbohydrates content alterations for wall assembly during hyphal growth at alkaline pH and temp. 37 degrees C. The study provided evidence for the relationship between morphogenesis, cell-cell adhesion induced by serum and changes in the level of carbohydrates content.

Method for improving separation of carbohydrates from wood pulping and wood or biomass hydrolysis liquors

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Griffith, William Louis; Compere, Alicia Lucille; Leitten, Jr., Carl Frederick

2010-04-20

A method for separating carbohydrates from pulping liquors includes the steps of providing a wood pulping or wood or biomass hydrolysis pulping liquor having lignin therein, and mixing the liquor with an acid or a gas which forms an acid upon contact with water to initiate precipitation of carbohydrate to begin formation of a precipitate. During precipitation, at least one long chain carboxylated carbohydrate and at least one cationic polymer, such as a polyamine or polyimine are added, wherein the precipitate aggregates into larger precipitate structures. Carbohydrate gel precipitates are then selectively removed from the larger precipitate structures. The method process yields both a carbohydrate precipitate and a high purity lignin.

Carbohydrates as efficient catalysts for the hydration of α-amino nitriles.

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Chitale, Sampada; Derasp, Joshua S; Hussain, Bashir; Tanveer, Kashif; Beauchemin, André M

2016-11-01

Directed hydration of α-amino nitriles was achieved under mild conditions using simple carbohydrates as catalysts exploiting temporary intramolecularity. A broadly applicable procedure using both formaldehyde and NaOH as catalysts efficiently hydrated a variety of primary and secondary susbtrates, and allowed the hydration of enantiopure substrates to proceed without racemization. This work also provides a rare comparison of the catalytic activity of carbohydrates, and shows that the simple aldehydes at the basis of chemical evolution are efficient organocatalysts mimicking the function of hydratase enzymes. Optimal catalytic efficiency was observed with destabilized aldehydes, and with difficult substrates only simple carbohydrates such as formaldehyde and glycolaldehyde proved reliable.

Streptococcus oralis Neuraminidase Modulates Adherence to Multiple Carbohydrates on Platelets

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Singh, Anirudh K.; Woodiga, Shireen A.; Grau, Margaret A.

2016-01-01

ABSTRACT Adherence to host surfaces is often mediated by bacterial binding to surface carbohydrates. Although it is widely appreciated that some bacterial species express glycosidases, previous studies have not considered whether bacteria bind to multiple carbohydrates within host glycans as they are modified by bacterial glycosidases. Streptococcus oralis is a leading cause of subacute infective endocarditis. Binding to platelets is a critical step in disease; however, the mechanisms utilized by S. oralis remain largely undefined. Studies revealed that S. oralis, like Streptococcus gordonii and Streptococcus sanguinis, binds platelets via terminal sialic acid. However, unlike those organisms, S. oralis produces a neuraminidase, NanA, which cleaves terminal sialic acid. Further studies revealed that following NanA-dependent removal of terminal sialic acid, S. oralis bound exposed β-1,4-linked galactose. Adherence to both these carbohydrates required Fap1, the S. oralis member of the serine-rich repeat protein (SRRP) family of adhesins. Mutation of a conserved residue required for sialic acid binding by other SRRPs significantly reduced platelet binding, supporting the hypothesis that Fap1 binds this carbohydrate. The mechanism by which Fap1 contributes to β-1,4-linked galactose binding remains to be defined; however, binding may occur via additional domains of unknown function within the nonrepeat region, one of which shares some similarity with a carbohydrate binding module. This study is the first demonstration that an SRRP is required to bind β-1,4-linked galactose and the first time that one of these adhesins has been shown to be required for binding of multiple glycan receptors. PMID:27993975

PHYSICO-CHEMICAL DETERMINATION OF CARBOHYDRATES IN THE FOODS AND BEVERAGES

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I. I. Korenman

2014-01-01

Full Text Available Summary. The extraction of fructose, glucose, galactose, sucrose and lactose from aqueous salt solutions, hydrophilic solvents (aliphatic alcohols, alkyl acetates, ketones of double and triple mixtures has been studied. Under identical conditions set quantitative characteristics extraction has been established. It was found that from the all studied carbohydrateы most fully extracted disaccharides lactose and sucrose. The conditions of concentration and almost complete recovery of carbohydrates from aqueous salt solutions has beenoptimized. The technique of extraction-potentiometric selective determination of carbohydrates in foods and beverages has been developed. As a titrant was used isopropanol solution of boric acid. The developed method allows to determine separately the mono- or disaccharides in milk, which include those contained 5 or less carbohydrates. The complex of photocolorimetric, polarimetric, potentiometric and chromatographic methods for determining carbohydrates in aqueous media and food (diabetic confectionery, juices, dairy products, honey wasproposed. To determine the fructose, glucose and sucrose in natural juices us used optical methods (photoelectrocolorimeters, polarimetry. Method is express, does not require expensive equipment and reagents. Fructose and sucrose in diabetic confectionery was determined by ascending thin layer chromatography. Some diabetic products based on fructose, produced by Russian confectionery factorieshas beenanalyzed. Duration analysis, 50-60 minutes, selective determination of error within 5-7%. Extracts from honey and milk were analyzed potentiometrically. We have developed a technique characterized by the following advantages compared with state standards: rapidity (analysis time 30-35 min, accuracy (relative error within 5 %, does not require expensive equipment and reagents, as well as dilution and filtration of milk stage sampling.

Soluble Sugars as the Carbohydrate Reserve for CAM in Pineapple Leaves 1

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Carnal, Nancy Wieland; Black, Clanton C.

1989-01-01

Neutral ethanol-soluble sugar pools serve as carbohydrate reserves for Crassulacean acid metabolism (CAM) in pineapple (Ananas comosus (L.) Merr.) leaves. Levels of neutral soluble sugars and glucans fluctuated reciprocally with concentrations of malic acid. Hexose loss from neutral soluble-sugar pools was sufficient to account for malic acid accumulation with about 95% of the required hexose accounted for by turnover of fructose and glucose pools. Hexose loss from starch or starch plus lower molecular weight glucan pools was insufficient to account for nocturnal accumulation of malic acid. The apparent maximum catalytic capacity of pyrophosphate:6-phosphofructokinase (PPi-PFK) at 15°C was about 16 times higher than the mean maximum rate of glycolysis that occurred to support malic acid accumulation in pineapple leaves at night and 12 times higher than the mean maximum rate of hexose turnover from all carbohydrate pools. The apparent maximum catalytic capacity of ATP-PFK at 15°C was about 70% of the activity required to account for the mean maximal rate of hexose turnover from all carbohydrate pools if turnover were completely via glycolysis, and marginally sufficient to account for mean maximal rates of acidification. Therefore, at low night temperatures conducive to CAM and under subsaturating substrate concentrations, PPi-PFK activity, but not ATP-PFK activity, would be sufficient to support the rate of glycolytic carbohydrate processing required for acid accumulation. These data for pineapple establish that there are at least two types of CAM plants with respect to the nature of the carbohydrate reserve utilized to support nighttime CO2 accumulation. The data further indicate that the glycolytic carbohydrate processing that supports acidification proceeds in different subcellular compartments in plants utilizing different carbohydrate reserves. PMID:16666775

Gut feedback mechanisms and food intake: a physiological approach to slow carbohydrate bioavailability.

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Zhang, Genyi; Hasek, Like Y; Lee, Byung-Hoo; Hamaker, Bruce R

2015-04-01

Glycemic carbohydrates in foods are an important macronutrient providing the biological fuel of glucose for a variety of physiological processes. A classification of glycemic carbohydrates into rapidly digestible carbohydrate (RDC) and slowly digestible carbohydrate (SDC) has been used to specify their nutritional quality related to glucose homeostasis that is essential to normal functioning of the brain and critical to life. Although there have been many studies and reviews on slowly digestible starch (SDS) and SDC, the mechanisms of their slow digestion and absorption were mostly investigated from the material side without considering the physiological processes of their in vivo digestion, absorption, and most importantly interactions with other food components and the gastrointestinal tract. In this article, the physiological processes modulating the bioavailability of carbohydrates, specifically the rate and extent of their digestion and absorption as well as the related locations, in a whole food context, will be discussed by focusing on the activities of the gastrointestinal tract including glycolytic enzymes and glucose release, sugar sensing, gut hormones, and neurohormonal negative feedback mechanisms. It is hoped that a deep understanding of these physiological processes will facilitate the development of innovative dietary approaches to achieve desired carbohydrate or glucose bioavailability for improved health.

Carbohydrates and the human gut microbiota.

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Chassard, Christophe; Lacroix, Christophe

2013-07-01

Due to its scale and its important role in maintaining health, the gut microbiota can be considered as a 'new organ' inside the human body. Many complex carbohydrates are degraded and fermented by the human gut microbiota in the large intestine to both yield basic energy salvage and impact gut health through produced metabolites. This review will focus on the gut microbes and microbial mechanisms responsible for polysaccharides degradation and fermentation in the large intestine. Gut microbes and bacterial metabolites impact the host at many levels, including modulation of inflammation, and glucose and lipid metabolisms. A complex relationship occurs in the intestine between the human gut microbiota, diet and the host. Research on carbohydrates and gut microbiota composition and functionality is fast developing and will open opportunities for prevention and treatment of obesity, diabetes and other related metabolic disorders through manipulation of the gut ecosystem.

Carbohydrate production, balance and translocation in leaves, shoots and fruits of Montmorency sour cherry

International Nuclear Information System (INIS)

Kappes, E.M.

1986-01-01

Carbohydrate production, export and use were studied for different organs of sour cherry (Prunus cerasus L. Montmorency). Gross carbohydrate ( 14 CO 2 ) export started between 27.2 and 77.6% of full leaf expansion. The 10th leaf developing started export later than the 7th leaf, suggesting that higher carbohydrate availability during leaf expansion delays export initiation. In support of this, gross export started earlier (44.4-52.4% full expansion) after source leaf removal, than in the control (77.6%). Translocation was primarily vertical (following orthostichies). Most leaves of fruiting shoots exported bidirectionally to the apex and fruits, only leaves closest to fruits exported exclusively to fruits during rapid cell division (Stage I) and rapid cell expansion (Stage III). Net export, determined from carbohydrate balance models started at 17 and 51% expansion for the 7th and terminal leaf, and at 26.5% of shoot elongation. Cumulative carbohydrate production of the 7th and terminal leaves during the first 9 and 11 days after emergence, exceeded carbohydrate accumulated at final size, 464.2 and 148.9 mg. A fruit carbohydrate balance was developed to determine contributions by fruit photosynthesis and fruit respiration, and to identify periods of greatest carbohydrate import. Fruit photosynthesis during development was characterized under different environmental conditions. Gross photosynthesis and chlorophyll content per fruit increased to a maximum during stage II and decreased thereafter. Gross photosynthesis approached a maximum at 40 0 C. Since dark respiration increased exponentially over the same temperature range, net photosynthesis reached a maximum at 18 0 C. Photorespiration was not detected

The growth of juvenile jaguar guapote (Cichlasoma managuense fed diets with different carbohydrate levels (ESP

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Juan B Ulloa R.

2016-03-01

Full Text Available The experiment was conducted in a 16 45 L aquaria recirculation system. The objective was to evaluate the growth of jaguar guapote (Cichlasoma managuense when fed isocaloric diets with increasing carbohydrate levels from 11 to 36 percent. Relative metabolic growth rate and feed conversion were similar with diets containing 11.5%, 18.8% and 26.5% carbohydrate (P > 0.05 . The highest protein efficiency ratio (PER and apparent net protein utilization (NPUa values were found with the 18.8% carbohydrate diet. Growth performance, feed utilization parameters and the survival were the lowest with fish fed the highest carbohydrate level (35.6%. Fish body protein increased and body fat decreased with increasing dietary carbohydrate levels. The body ash showed a trend similar to the body protein. It is concluded that juvenile C. managuense can grow well when fed 40% protein diets containing up to 26.5% carbohydrate.

Low-carbohydrate-diet score and metabolic syndrome: An epidemiologic study among Iranian women.

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Shirani, Fatemeh; Esmaillzadeh, Ahmad; Keshteli, Ammar Hassanzadeh; Adibi, Peyman; Azadbakht, Leila

2015-09-01

Epidemiologic studies linking carbohydrate consumption and risk for metabolic syndrome (MetS) are limited. The association between low-carbohydrate-diet score and MetS has not been investigated. The aim of this study was to investigate low-carbohydrate-diet score in relation to MetS among a group of Iranian women. This cross-sectional study was conducted with 442 Iranian female teachers >20 y of age. Usual dietary intakes were assessed using a validated, dish-based semiquantitative food frequency questionnaire. Metabolic syndrome was defined according to the American Heart Association/National Heart, Lung, and Blood Institute/International Diabetes Federation definition guidelines. The prevalence of MetS in the lowest and highest quintile of low-carbohydrate-diet score was 17.5% and 18.8%, respectively (P = 0.97). There was no statistically significant difference in the prevalence between extreme quartiles low-carbohydrate-diet score and MetS (odds ratio, 0.93; 95% confidence interval, 0.38-2.28). After controlling for age, energy intake, and other potential confounders, low-carbohydrate-diet score was not significantly associated with MetS. A significant association was observed between this score and abnormal fasting plasma glucose. We failed to find a significant relationship between this score and other components of MetS. Diets with lower amounts of carbohydrate and higher contents of fat and protein were not significantly associated with the risk for MetS in a cross-sectional study with a group of Iranian women. More longitudinal studies are needed to confirm these results. Copyright © 2015 Elsevier Inc. All rights reserved.

Levorotatory carbohydrates and xylitol subdue Streptococcus mutans and Candida albicans adhesion and biofilm formation.

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Brambilla, Eugenio; Ionescu, Andrei C; Cazzaniga, Gloria; Ottobelli, Marco; Samaranayake, Lakshman P

2016-05-01

Dietary carbohydrates and polyols affect the microbial colonization of oral surfaces by modulating adhesion and biofilm formation. The aim of this study was to evaluate the influence of a select group of l-carbohydrates and polyols on either Streptococcus mutans or Candida albicans adhesion and biofilm formation in vitro. S. mutans or C. albicans suspensions were inoculated on polystyrene substrata in the presence of Tryptic soy broth containing 5% of the following compounds: d-glucose, d-mannose, l-glucose, l-mannose, d- and l-glucose (raceme), d- and l-mannose (raceme), l-glucose and l-mannose, sorbitol, mannitol, and xylitol. Microbial adhesion (2 h) and biofilm formation (24 h) were evaluated using MTT-test and Scanning Electron Microscopy (SEM). Xylitol and l-carbohydrates induced the lowest adhesion and biofilm formation in both the tested species, while sorbitol and mannitol did not promote C. albicans biofilm formation. Higher adhesion and biofilm formation was noted in both organisms in the presence of d-carbohydrates relative to their l-carbohydrate counterparts. These results elucidate, hitherto undescribed, interactions of the individually tested strains with l- and d-carbohydrates, and how they impact fungal and bacterial colonization. In translational terms, our data raise the possibility of using l-form of carbohydrates and xylitol for dietary control of oral plaque biofilms. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Raman and infrared spectroscopy of carbohydrates: A review

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Wiercigroch, Ewelina; Szafraniec, Ewelina; Czamara, Krzysztof; Pacia, Marta Z.; Majzner, Katarzyna; Kochan, Kamila; Kaczor, Agnieszka; Baranska, Malgorzata; Malek, Kamilla

2017-10-01

Carbohydrates are widespread and naturally occurring compounds, and essential constituents for living organisms. They are quite often reported when biological systems are studied and their role is discussed. However surprisingly, up till now there is no database collecting vibrational spectra of carbohydrates and their assignment, as has been done already for other biomolecules. So, this paper serves as a comprehensive review, where for selected 14 carbohydrates in the solid state both FT-Raman and ATR FT-IR spectra were collected and assigned. Carbohydrates can be divided into four chemical groups and in the same way is organized this review. First, the smallest molecules are discussed, i.e. monosaccharides (D-(-)-ribose, 2-deoxy-D-ribose, L-(-)-arabinose, D-(+)-xylose, D-(+)-glucose, D-(+)-galactose and D-(-)-fructose) and disaccharides (D-(+)-sucrose, D-(+)-maltose and D-(+)-lactose), and then more complex ones, i.e. trisaccharides (D-(+)-raffinose) and polysaccharides (amylopectin, amylose, glycogen). Both Raman and IR spectra were collected in the whole spectral range and discussed looking at the specific regions, i.e. region V (3600-3050 cm- 1), IV (3050-2800 cm- 1) and II (1200-800 cm- 1) assigned to the stretching vibrations of the OH, CH/CH2 and C-O/C-C groups, respectively, and region III (1500-1200 cm- 1) and I (800-100 cm- 1) dominated by deformational modes of the CH/CH2 and CCO groups, respectively. In spite of the fact that vibrational spectra of saccharides are significantly less specific than spectra of other biomolecules (e.g. lipids or proteins), marker bands of the studied molecules can be identified and correlated with their structure.

Aspartame in conjunction with carbohydrate reduces insulin levels during endurance exercise

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Siegler Jason

2012-08-01

Full Text Available Abstract Background As most sport drinks contain some form of non-nutritive sweetener (e.g. aspartame, and with the variation in blood glucose regulation and insulin secretion reportedly associated with aspartame, a further understanding of the effects on insulin and blood glucose regulation during exercise is warranted. Therefore, the aim of this preliminary study was to profile the insulin and blood glucose responses in healthy individuals after aspartame and carbohydrate ingestion during rest and exercise. Findings Each participant completed four trials under the same conditions (45 min rest + 60 min self-paced intense exercise differing only in their fluid intake: 1 carbohydrate (2% maltodextrin and 5% sucrose (C; 2 0.04% aspartame with 2% maltodextrin and 5% sucrose (CA; 3 water (W; and 4 aspartame (0.04% aspartame with 2% maltodextrin (A. Insulin levels dropped significantly for CA versus C alone (43% between pre-exercise and 30 min, while W and A insulin levels did not differ between these time points. Conclusions Aspartame with carbohydrate significantly lowered insulin levels during exercise versus carbohydrate alone.

Effects of Substituting Palm Olein with Carbohydrates on Insulin Sensitivity: A Review

International Nuclear Information System (INIS)

Kim-Tiu, T.; Faun, C.L.

2016-01-01

The role of palm olein on insulin resistance, which predisposes to disease progression of type 2 diabetes, is unclear. This article summarises the effects of substituting palm olein with carbohydrates on insulin sensitivity. Two intervention studies have reported conflicting findings. The RISCK (Reading, Imperial, Surreys, Cambridge and King's) study suggested that saturated fat-enriched diet consisting of mainly palm oil and milk fat did not differ from both high and low glycemic carbohydrates on insulin sensitivity in subjects at risk of developing metabolic syndrome. However, another study reported reduced insulin sensitivity after a diet enriched with palm olein and butter compared with high carbohydrate intake. No epidemiological data exists in this context. More clinical trials using solely palm olein in this area are needed. Further well-controlled large scale studies are needed to furnish the information on palm olein replacement with carbohydrates in diabetes prevention. (author)

Continuous fermentation of carbohydrate-containing liquids to alcohol

Energy Technology Data Exchange (ETDEWEB)

Moldenhauer, O; Lechner, R

1955-08-25

Rate of alcohol fermentation depends mostly on the biological state of the yeast. The process described avoids retardation during the final fermentation phase by increasing the concentration of yeast as the fermentation proceeds. The method is especially suitable for dilute carbohydrate solutions. Thus, to a solution containing 4% carbohydrates, 66 g pressed yeast was added. This mash was passed continuously through several fermentation vessels. The temperature was adjusted to 29 to 35 degrees according to the type of yeast. Before entering the next vessel, another portion of pressed yeast (66 g/1 of mash) is added. The yeast is recovered from the fermented mash by means of a yeast separator.

Continuous fermentation of carbohydrate-containing liquids to alcohol

Energy Technology Data Exchange (ETDEWEB)

Moldenhauer, O; Lechner, R

1955-08-29

Rate of alcohol fermentation depends mostly on the biological state of the yeast. The process described avoids retardation during the final fermentation phase by increasing the concentration of yeast as the fermentation proceeds. The method is especially suitable for dilute carbohydrate solutions. Thus, to a solution containing 4% carbohydrates, 66 g pressed yeast was added. This mash was passed continuously through several fermentation vessels. The temperature was adjusted to 29 to 35/sup 0/ according to the type of yeast. Before entering the next vessel, another portion of pressed yeast (66 g/l of mash) is added. The yeast is recovered from the fermented mash by means of a yeast separator.

Transcriptional regulation of the carbohydrate utilization network in Thermotoga maritima

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Dmitry A Rodionov

2013-08-01

Full Text Available Hyperthermophilic bacteria from the Thermotogales lineage can produce hydrogen by fermenting a wide range of carbohydrates. Previous experimental studies identified a large fraction of genes committed to carbohydrate degradation and utilization in the model bacterium Thermotoga maritima. Knowledge of these genes enabled comprehensive reconstruction of biochemical pathways comprising the carbohydrate utilization network. However, transcriptional factors (TFs and regulatory mechanisms driving this network remained largely unknown. Here, we used an integrated approach based on comparative analysis of genomic and transcriptomic data for the reconstruction of the carbohydrate utilization regulatory networks in 11 Thermotogales genomes. We identified DNA-binding motifs and regulons for 19 orthologous TFs in the Thermotogales. The inferred regulatory network in T. maritima contains 181 genes encoding TFs, sugar catabolic enzymes and ABC-family transporters. In contrast to many previously described bacteria, a transcriptional regulation strategy of Thermotoga does not employ global regulatory factors. The reconstructed regulatory network in T. maritima was validated by gene expression profiling on a panel of mono- and disaccharides and by in vitro DNA-binding assays. The observed upregulation of genes involved in catabolism of pectin, trehalose, cellobiose, arabinose, rhamnose, xylose, glucose, galactose, and ribose showed a strong correlation with the UxaR, TreR, BglR, CelR, AraR, RhaR, XylR, GluR, GalR, and RbsR regulons. Ultimately, this study elucidated the transcriptional regulatory network and mechanisms controlling expression of carbohydrate utilization genes in T. maritima. In addition to improving the functional annotations of associated transporters and catabolic enzymes, this research provides novel insights into the evolution of regulatory networks in Thermotogales.

Streptococcus oralis Neuraminidase Modulates Adherence to Multiple Carbohydrates on Platelets.

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Singh, Anirudh K; Woodiga, Shireen A; Grau, Margaret A; King, Samantha J

2017-03-01

Adherence to host surfaces is often mediated by bacterial binding to surface carbohydrates. Although it is widely appreciated that some bacterial species express glycosidases, previous studies have not considered whether bacteria bind to multiple carbohydrates within host glycans as they are modified by bacterial glycosidases. Streptococcus oralis is a leading cause of subacute infective endocarditis. Binding to platelets is a critical step in disease; however, the mechanisms utilized by S. oralis remain largely undefined. Studies revealed that S. oralis , like Streptococcus gordonii and Streptococcus sanguinis , binds platelets via terminal sialic acid. However, unlike those organisms, S. oralis produces a neuraminidase, NanA, which cleaves terminal sialic acid. Further studies revealed that following NanA-dependent removal of terminal sialic acid, S. oralis bound exposed β-1,4-linked galactose. Adherence to both these carbohydrates required Fap1, the S. oralis member of the serine-rich repeat protein (SRRP) family of adhesins. Mutation of a conserved residue required for sialic acid binding by other SRRPs significantly reduced platelet binding, supporting the hypothesis that Fap1 binds this carbohydrate. The mechanism by which Fap1 contributes to β-1,4-linked galactose binding remains to be defined; however, binding may occur via additional domains of unknown function within the nonrepeat region, one of which shares some similarity with a carbohydrate binding module. This study is the first demonstration that an SRRP is required to bind β-1,4-linked galactose and the first time that one of these adhesins has been shown to be required for binding of multiple glycan receptors. Copyright © 2017 American Society for Microbiology.

Oxygen isotope fractionations across individual leaf carbohydrates in grass and tree species.

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Lehmann, Marco M; Gamarra, Bruno; Kahmen, Ansgar; Siegwolf, Rolf T W; Saurer, Matthias

2017-08-01

Almost no δ 18 O data are available for leaf carbohydrates, leaving a gap in the understanding of the δ 18 O relationship between leaf water and cellulose. We measured δ 18 O values of bulk leaf water (δ 18 O LW ) and individual leaf carbohydrates (e.g. fructose, glucose and sucrose) in grass and tree species and δ 18 O of leaf cellulose in grasses. The grasses were grown under two relative humidity (rH) conditions. Sucrose was generally 18 O-enriched compared with hexoses across all species with an apparent biosynthetic fractionation factor (ε bio ) of more than 27‰ relative to δ 18 O LW , which might be explained by isotopic leaf water and sucrose synthesis gradients. δ 18 O LW and δ 18 O values of carbohydrates and cellulose in grasses were strongly related, indicating that the leaf water signal in carbohydrates was transferred to cellulose (ε bio  = 25.1‰). Interestingly, damping factor p ex p x , which reflects oxygen isotope exchange with less enriched water during cellulose synthesis, responded to rH conditions if modelled from δ 18 O LW but not if modelled directly from δ 18 O of individual carbohydrates. We conclude that δ 18 O LW is not always a good substitute for δ 18 O of synthesis water due to isotopic leaf water gradients. Thus, compound-specific δ 18 O analyses of individual carbohydrates are helpful to better constrain (post-)photosynthetic isotope fractionation processes in plants. © 2017 John Wiley & Sons Ltd.

Dietary fiber content influences soluble carbohydrate levels in ruminal fluids.

Science.gov (United States)

Pinder, R S; Patterson, J A; O'Bryan, C A; Crandall, P G; Ricke, S C

2012-01-01

The soluble carbohydrate concentration of ruminal fluid, as affected by dietary forage content (DFC) and/or ruminally undegradable intake protein content (UIPC), was determined. Four ruminally cannulated steers, in a 4 × 4 Latin square design, were offered diets containing high (75 % of DM) or low (25 % of DM) DFC and high (6 % of DM) or low (5 % of DM) UIPC, in a 2 × 2 factorial arrangement. Zinc-treated SBM was the primary UIP source. Soluble hexose concentration (145.1 μM) in ruminal fluid (RF) of steers fed low DFC diets exhibited a higher trend (P = 0.08) than that (124.5 μM) of steers fed high DFC diets. UIPC did not modulate (P = 0.54) ruminal soluble hexose concentrations. Regardless of diet, soluble hexose concentration declined immediately after feeding and did not rise until 3 h after feeding (P ruminal fluid could not be determined. However, unsubstituted xylose and arabinose were excluded. These data indicate that: (i) soluble carbohydrate concentrations remain in ruminal fluid during digestion and fermentation; (ii) slight diurnal changes began after feeding; (iii) DFC influences the soluble carbohydrate concentration in RF; and (iv) UIPC of these diets does not affect the soluble carbohydrate concentration of RF.

Saturated fat, carbohydrates and cardiovascular disease

NARCIS (Netherlands)

Kuipers, R. S.; de Graaf, D. J.; Luxwolda, M. F.; Muskiet, M. H. A.; Dijck-Brouwer, D. A. J.; Muskiet, F. A. J.

The dietary intake of saturated fatty acids (SAFA) is associated with a modest increase in serum total cholesterol, but not with cardiovascular disease (CVD). Replacing dietary SAFA with carbohydrates (CHO), notably those with a high glycaemic index, is associated with an increase in CVD risk in

Equine colostral carbohydrates reduce lipopolysaccharide-induced inflammatory responses in equine peripheral blood mononuclear cells.

Science.gov (United States)

Vendrig, J C; Coffeng, L E; Fink-Gremmels, J

2012-12-01

Increasing evidence suggests that reactions to lipopolysaccharide (LPS), particularly in the gut, can be partly or completely mitigated by colostrum- and milk-derived oligosaccharides. Confirmation of this hypothesis could lead to the development of new therapeutic concepts. To demonstrate the influence of equine colostral carbohydrates on the inflammatory response in an in vitro model with equine peripheral blood mononuclear cells (PBMCs). Carbohydrates were extracted from mare colostrum, and then evaluated for their influence on LPS-induced inflammatory responses in PBMCs isolated from the same mares, mRNA expression of tumour necrosis factor-alpha, interleukin-6 and interleukin-10 was measured as well as the protein levels of tumour necrosis factor-alpha (TNF-alpha) and interleukin-10 (IL-10). Equine colostral carbohydrates significantly reduced LPS-induced TNF-alpha protein at both times measured and significantly reduced LPS-induced TNF-alpha, IL-6 and IL-10 mRNA expression by PBMCs. Moreover, cell viability significantly increased in the presence of high concentrations of colostral carbohydrates. Carbohydrates derived from equine colostrum reduce LPS-induced inflammatory responses of equine PBMCs. Colostrum and milk-derived carbohydrates are promising candidates for new concepts in preventive and regenerative medicine.

Effect of carbohydrate intake on de novo lipogenesis in human adipose tissue

International Nuclear Information System (INIS)

Chascione, C.; Elwyn, D.H.; Davila, M.; Gil, K.M.; Askanazi, J.; Kinney, J.M.

1987-01-01

Rates of synthesis, from [ 14 C]glucose, of fatty acids (de novo lipogenesis) and glycerol (triglyceride synthesis) were measured in biopsies of adipose tissue from nutritionally depleted patients given low- or high-carbohydrate intravenous nutrition. Simultaneously, energy expenditure and whole-body lipogenesis were measured by indirect calorimetry. Rates of whole-body lipogenesis were zero on the low-carbohydrate diet and averaged 1.6 g·kg -1 ·day -1 on the high-carbohydrate diet. In vitro rates of triglyceride synthesis increased 3-fold going from the low to the high intake; rates of fatty acid synthesis increased ∼80-fold. In vitro, lipogenesis accounted for <0.1% of triglyceride synthesis on the low intake and 4% on the high intake. On the high-carbohydrate intake, in vitro rates of triglyceride synthesis accounted for 61% of the rates of unidirectional triglyceride synthesis measured by indirect calorimetry. In vitro rates of lipogenesis accounted for 7% of whole-body lipogenesis. Discrepancies between in vitro rates of fatty acid synthesis from glucose, compared with acetate and citrate, as reported by others, suggest that in depleted patients on hypercaloric high-carbohydrate diets, adipose tissue may account for up to 40% of whole-body lipogenesis

Carbohydrates Components of Some Italian Local Landraces: Garlic (Allium sativum L.

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Silvia Lisciani

2017-10-01

Full Text Available Garlic is one of the most widespread and ancient medicinal plants. Its health benefits are due to its chemical components, and among these is carbohydrate, whose characteristics have been so far little investigated. The aim of this study is to typify the various components of carbohydrate (starch, individual sugars, fructans, and total dietary fibre in four commonly consumed “Italian local landraces”: Bianco Piacentino, Rosso di Castelliri, Rosso di Sulmona, Rosso di Proceno, which are grown in two different geographical areas—Viterbo and Alvito—under the same agronomic conditions. This study will also evaluate how genotype and the cultivation area can affect the profile of the carbohydrate components of these landrace strains. Regarding unavailable carbohydrates, all of the varieties showed appreciable contents of fructans, the most representative component, which ranged from 45.8 to 54.4 g/100 g d.w. In contrast, total dietary fibre values varied from 9.1 to 13.1 g/100 g d.w. in Rosso di Castelliri and Bianco Piacentino, respectively, which are both grown in Viterbo. As for starch, only some traces were found, while the amount of total sugars ranged between 2.12 and 3.27 g/100 g d.w., with higher levels of sucrose. Our findings could provide important information that may be adopted to enhance and promote the quality of some local Italian garlic landraces through highlighting the influence that the cultivar and the environmental conditions can have on carbohydrates components.

[The participation of ethanol in induction of carbohydrates metabolism disturbances].

Science.gov (United States)

Orywal, Karolina; Jelski, Wojciech; Szmitkowski, Maciej

2009-07-01

Alcohol and products of its metabolism lead to impairment of many organs functions, what cause systemic and local carbohydrates metabolism disturbances. Abusing of alcohol induces changes in pancreatic digestive enzymes secretion, what contributes to development of chronic alcoholic pancreatitis. Alcohol can cause secondary diabetes, what is result of pancreatic beta-cells damage and is a risk factor for type 2 diabetes. Alcohol cause liver cells degeneration and induction of many metabolic disturbances especially carbohydrates.

A low-carbohydrate as compared with a low-fat diet in severe obesity.

Science.gov (United States)

Samaha, Frederick F; Iqbal, Nayyar; Seshadri, Prakash; Chicano, Kathryn L; Daily, Denise A; McGrory, Joyce; Williams, Terrence; Williams, Monica; Gracely, Edward J; Stern, Linda

2003-05-22

The effects of a carbohydrate-restricted diet on weight loss and risk factors for atherosclerosis have been incompletely assessed. We randomly assigned 132 severely obese subjects (including 77 blacks and 23 women) with a mean body-mass index of 43 and a high prevalence of diabetes (39 percent) or the metabolic syndrome (43 percent) to a carbohydrate-restricted (low-carbohydrate) diet or a calorie- and fat-restricted (low-fat) diet. Seventy-nine subjects completed the six-month study. An analysis including all subjects, with the last observation carried forward for those who dropped out, showed that subjects on the low-carbohydrate diet lost more weight than those on the low-fat diet (mean [+/-SD], -5.8+/-8.6 kg vs. -1.9+/-4.2 kg; P=0.002) and had greater decreases in triglyceride levels (mean, -20+/-43 percent vs. -4+/-31 percent; P=0.001), irrespective of the use or nonuse of hypoglycemic or lipid-lowering medications. Insulin sensitivity, measured only in subjects without diabetes, also improved more among subjects on the low-carbohydrate diet (6+/-9 percent vs. -3+/-8 percent, P=0.01). The amount of weight lost (Plow-carbohydrate diet (P=0.01) were independent predictors of improvement in triglyceride levels and insulin sensitivity. Severely obese subjects with a high prevalence of diabetes or the metabolic syndrome lost more weight during six months on a carbohydrate-restricted diet than on a calorie- and fat-restricted diet, with a relative improvement in insulin sensitivity and triglyceride levels, even after adjustment for the amount of weight lost. This finding should be interpreted with caution, given the small magnitude of overall and between-group differences in weight loss in these markedly obese subjects and the short duration of the study. Future studies evaluating long-term cardiovascular outcomes are needed before a carbohydrate-restricted diet can be endorsed. Copyright 2003 Massachusetts Medical Society

Drought response strategies define the relative contributions of hydraulic dysfunction and carbohydrate depletion during tree mortality.

Science.gov (United States)

Mitchell, Patrick J; O'Grady, Anthony P; Tissue, David T; White, Donald A; Ottenschlaeger, Maria L; Pinkard, Elizabeth A

2013-02-01

Plant survival during drought requires adequate hydration in living tissues and carbohydrate reserves for maintenance and recovery. We hypothesized that tree growth and hydraulic strategy determines the intensity and duration of the 'physiological drought', thereby affecting the relative contributions of loss of hydraulic function and carbohydrate depletion during mortality. We compared patterns in growth rate, water relations, gas exchange and carbohydrate dynamics in three tree species subjected to prolonged drought. Two Eucalyptus species (E. globulus, E. smithii) exhibited high growth rates and water-use resulting in rapid declines in water status and hydraulic conductance. In contrast, conservative growth and water relations in Pinus radiata resulted in longer periods of negative carbon balance and significant depletion of stored carbohydrates in all organs. The ongoing demand for carbohydrates from sustained respiration highlighted the role that duration of drought plays in facilitating carbohydrate consumption. Two drought strategies were revealed, differentiated by plant regulation of water status: plants maximized gas exchange, but were exposed to low water potentials and rapid hydraulic dysfunction; and tight regulation of gas exchange at the cost of carbohydrate depletion. These findings provide evidence for a relationship between hydraulic regulation of water status and carbohydrate depletion during terminal drought. © 2012 CSIRO. New Phytologist © 2012 New Phytologist Trust.

Chemical biology based on target-selective degradation of proteins and carbohydrates using light-activatable organic molecules.

Science.gov (United States)

Toshima, Kazunobu

2013-05-01

Proteins and carbohydrates play crucial roles in a wide range of biological processes, including serious diseases. The development of novel and innovative methods for selective control of specific proteins and carbohydrates functions has attracted much attention in the field of chemical biology. In this account article, the development of novel chemical tools, which can degrade target proteins and carbohydrates by irradiation with a specific wavelength of light under mild conditions without any additives, is introduced. This novel class of photochemical agents promise bright prospects for finding not only molecular-targeted bioprobes for understanding of the structure-activity relationships of proteins and carbohydrates but also novel therapeutic drugs targeting proteins and carbohydrates.

Glycan Reader: Automated Sugar Identification and Simulation Preparation for Carbohydrates and Glycoproteins

Science.gov (United States)

Jo, Sunhwan; Song, Kevin C.; Desaire, Heather; MacKerell, Alexander D.; Im, Wonpil

2011-01-01

Understanding how glycosylation affects protein structure, dynamics, and function is an emerging and challenging problem in biology. As a first step toward glycan modeling in the context of structural glycobiology, we have developed Glycan Reader and integrated it into the CHARMM-GUI, http://www.charmm-gui.org/input/glycan. Glycan Reader greatly simplifies the reading of PDB structure files containing glycans through (i) detection of carbohydrate molecules, (ii) automatic annotation of carbohydrates based on their three-dimensional structures, (iii) recognition of glycosidic linkages between carbohydrates as well as N-/O-glycosidic linkages to proteins, and (iv) generation of inputs for the biomolecular simulation program CHARMM with the proper glycosidic linkage setup. In addition, Glycan Reader is linked to other functional modules in CHARMM-GUI, allowing users to easily generate carbohydrate or glycoprotein molecular simulation systems in solution or membrane environments and visualize the electrostatic potential on glycoprotein surfaces. These tools are useful for studying the impact of glycosylation on protein structure and dynamics. PMID:21815173

Microalgal carbohydrates: an overview of the factors influencing carbohydrates production, and of main bioconversion technologies for production of biofuels

DEFF Research Database (Denmark)

Markou, Giorgos; Angelidaki, Irini; Georgakakis, Dimitris

2012-01-01

in research is the cultivation of microalgae for lipids production to generate biodiesel. However, there are several other biological or thermochemical conversion technologies, in which microalgal biomass could be used as substrate. However, the high protein content or the low carbohydrate content...... of the majority of the microalgal species might be a constraint for their possible use in these technologies. Moreover, in the majority of biomass conversion technologies, carbohydrates are the main substrate for production of biofuels. Nevertheless, microalgae biomass composition could be manipulated by several......Microalgal biomass seems to be a promising feedstock for biofuel generation. Microalgae have relative high photosynthetic efficiencies, high growth rates, and some species can thrive in brackish water or seawater and wastewater from the food- and agro-industrial sector. Today, the main interest...

Carbohydrate-Restriction with High-Intensity Interval Training: An Optimal Combination for Treating Metabolic Diseases?

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Monique E. Francois

2017-10-01

Full Text Available Lifestyle interventions incorporating both diet and exercise strategies remain cornerstone therapies for treating metabolic disease. Carbohydrate-restriction and high-intensity interval training (HIIT have independently been shown to improve cardiovascular and metabolic health. Carbohydrate-restriction reduces postprandial hyperglycemia, thereby limiting potential deleterious metabolic and cardiovascular consequences of excessive glucose excursions. Additionally, carbohydrate-restriction has been shown to improve body composition and blood lipids. The benefits of exercise for improving insulin sensitivity are well known. In this regard, HIIT has been shown to rapidly improve glucose control, endothelial function, and cardiorespiratory fitness. Here, we report the available evidence for each strategy and speculate that the combination of carbohydrate-restriction and HIIT will synergistically maximize the benefits of both approaches. We hypothesize that this lifestyle strategy represents an optimal intervention to treat metabolic disease; however, further research is warranted in order to harness the potential benefits of carbohydrate-restriction and HIIT for improving cardiometabolic health.

Carbohydrate-Restriction with High-Intensity Interval Training: An Optimal Combination for Treating Metabolic Diseases?

Science.gov (United States)

Francois, Monique E; Gillen, Jenna B; Little, Jonathan P

2017-01-01

Lifestyle interventions incorporating both diet and exercise strategies remain cornerstone therapies for treating metabolic disease. Carbohydrate-restriction and high-intensity interval training (HIIT) have independently been shown to improve cardiovascular and metabolic health. Carbohydrate-restriction reduces postprandial hyperglycemia, thereby limiting potential deleterious metabolic and cardiovascular consequences of excessive glucose excursions. Additionally, carbohydrate-restriction has been shown to improve body composition and blood lipids. The benefits of exercise for improving insulin sensitivity are well known. In this regard, HIIT has been shown to rapidly improve glucose control, endothelial function, and cardiorespiratory fitness. Here, we report the available evidence for each strategy and speculate that the combination of carbohydrate-restriction and HIIT will synergistically maximize the benefits of both approaches. We hypothesize that this lifestyle strategy represents an optimal intervention to treat metabolic disease; however, further research is warranted in order to harness the potential benefits of carbohydrate-restriction and HIIT for improving cardiometabolic health.

Oxalic acid pretreatment of rice straw particles and loblolly pine chips : release of hemicellulosic carbohydrates

Science.gov (United States)

Xianjun Li; Zhiyong Cai; Eric Horn; Jerrold E. Winandy

2011-01-01

This study was conducted to evaluate the effect of oxalic acid (OA) pretreatment on carbohydrates released from rice straw particles and wood chips. The results showed that OA treatment accelerated carbohydrates extraction from rice straw particles and wood chips. OA pretreatment dramatically increased the amount of carbohydrates extracted, up to 24 times for wood...

Relative mobility of 1-H atoms of carbohydrates in heterogeneous isotope exchange reactions

International Nuclear Information System (INIS)

Akulov, G.P.; Snetkova, E.V.; Kayumov, V.G.; Kaminskii, Yu.L.

1988-01-01

The method of competitive reactions was used to determine the relative mobilities of the 1-H atoms of carbohydrates in reactions of heterogeneous isotope exchange, using various reference standards, catalysts, and buffer systems. On the basis of the results obtained, the investigated carbohydrates are ranged in a series of decreasing mobility of the hydrogen atoms exchanged in heterogeneous isotope exchange reactions. It was demonstrated that the mobility of the 1-H atoms is related to the concentration of the acyclic forms of the carbohydrates

Synthesis of new enantiopure poly(hydroxyaminooxepanes as building blocks for multivalent carbohydrate mimetics

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Léa Bouché

2014-01-01

Full Text Available New compounds with carbohydrate-similar structure (carbohydrate mimetics are presented in this article. Starting from enantiopure nitrones and lithiated TMSE-allene we prepared three 1,2-oxazine derivatives which underwent a highly stereoselective Lewis acid-induced rearrangement to give bicyclic products in good yield. Subsequent reductive transformations delivered a library of new poly(hydroxyaminooxepane derivatives. The crucial final palladium-catalyzed hydrogenolysis of the 1,2-oxazine moiety was optimized resulting in a reasonably efficient approach to a series of new seven-membered carbohydrate mimetics.

The role and requirements of digestible dietary carbohydrates in infants and toddlers

NARCIS (Netherlands)

Stephen, A.; Alles, M.; Graaf, de C.; Fleith, M.; Hadjilucas, E.; Isaacs, A.; Maffeis, C.; Zeinstra, G.G.; Gil, A.

2012-01-01

Digestible carbohydrates are one of the main sources of dietary energy in infancy and childhood and are essential for growth and development. The aim of this narrative review is to outline the intakes of digestible carbohydrates and their role in health and disease, including the development of food

Comparing carbohydrate status during norway spruce seed development and somatic embryo formation

NARCIS (Netherlands)

Gösslová, M.; Svobodová, H.; Lipavská, H.; Albrechtová, J.; Vreugdenhil, D.

2001-01-01

The carbohydrate status of developing seeds of Picea abies was examined in order to provide a frame of reference for the evaluation of changes in carbohydrate content in maturing somatic embryos of the same species. Samples were taken at weekly intervals from 12 May 1998 (estimated time of

Carbohydrate production by phytoplankton and degradation in the marine microbial food web

NARCIS (Netherlands)

Alderkamp, Anne-Carlijn

2006-01-01

In this PhD thesis I describe studies relating to the cycling of the algal storage glucan chrysolaminaran. Chrysolaminaran is the most abundant type of storage carbohydrate in marine phytoplankton. I choose it as a model substrate to study factors influencing the cycling of carbohydrates, one of the

Spatiotemporal variation characteristics and related affecting factors of dissolved carbohydrates in the East China Sea

Science.gov (United States)

He, Zhen; Wang, Qi; Yang, Gui-Peng; Gao, Xian-Chi; Wu, Guan-Wei

2015-10-01

Carbohydrates are the largest identified fraction of dissolved organic carbon and play an important role in biogeochemical cycling in the ocean. Seawater samples were collected from the East China Sea (ECS) during June and October 2012 to study the spatiotemporal distributions of total dissolved carbohydrates (TCHOs) constituents, including dissolved monosaccharides (MCHOs) and polysaccharides (PCHOs). The concentrations of TCHOs, MCHOs and PCHOs showed significant differences between summer and autumn 2012, and exhibited an evident diurnal variation, with high values occurring in the daytime. Phytoplankton biomass was identified as the primary factor responsible for seasonal and diurnal variations of dissolved carbohydrates in the ECS. The TCHOs, MCHOs and PCHOs distributions in the study area displayed similar distribution patterns, with high concentrations appearing in the coastal water. The influences of chlorophyll-a, salinity and nutrients on the distributions of these carbohydrates were examined. A carbohydrate enrichment in the near-bottom water was found at some stations, implying that there might be an important source of carbohydrate in the deep water or bottom sediment.

Effect of Low ph on Carbohydrate Production by a Marine Planktonic Diatom (Chaetoceros muelleri)

International Nuclear Information System (INIS)

Thornton, D.C.O.

2009-01-01

Rising carbon dioxide (CO 2 ) concentrations in the atmosphere due to human activity are causing the surface ocean to become more acidic. Diatoms play a pivotal role in biogeochemical cycling and ecosystem function in the ocean. ph affected the quantum efficiency of photosystem II and carbohydrate metabolism in a planktonic diatom (Chaetoceros muelleri), representative of a widely distributed genus. In batch cultures grown at low ph, the proportion of total carbohydrate stored within the cells decreased and more dissolved carbohydrates were exuded from the cells into the surrounding medium. Changes in productivity and the way in which diatoms allocate carbon into carbohydrates may affect ecosystem function and the efficiency of the biological carbon pump in a low ph ocean.

Studies on soluble carbohydrates in yellow lupin (Lupinus luteus L. seeds of different age

Directory of Open Access Journals (Sweden)

Kazimierz Zalewski

2011-01-01

Full Text Available Yellow lupin seeds cv. Juno were stored under laboratory conditions for 2 month, 4, 6 and 8 years. Eighteen soluble carbohydrates were identified in embryonic axes and cotyledons of different age seeds. The concentration of soluble carbohydrates in analysed seeds ranged from 25 to 34% of dry mass. Axes contained more carbohydrates than cotyledons. Stachyose dominated in axes, and verbascose - in cotyledons. Other detected galactosides were: galactinol, galactosyl pinitols and galactosyl chiro-inositols (fagopyritols, but their content was several-fold lower than that of RFOs (in both axes and cotyledons tissues. The concentration of soluble carbohydrates indicated, that sucrose to RFOs mass ratio, or other changes in sugars composition are not indicators of seed storage.

[Carbohydrates metabolism disturbances when simulating prenatal alcohol intoxication].

Science.gov (United States)

Kurch, N M; Vysokogorskiĭ, V E

2013-01-01

The influence of prenatal alcohol intoxication on carbohydrate metabolism markers has been investigated at different terms of postnatal offspring development (15, 30 and 60 days). Plasma glucose decreased as compared with the same in control group was detected. In the liver homogenates an increase of phosphorylase activity and a decrease of glucose-6-phosphatase, aldolase and glucose-6-phosphate dehydrogenase activities were found. These changes were accompanied by the incease in the lactate/pyruvate index attributed to increased lactate content in the liver tissue. The obtained data indicate essential disturbances of carbohydrate metabolism markers in prenatal alcoholized offspring, which include stable hypoglycemia, suppression of glycolytic and pentosephosphate pathways of glucose metabolism and lactate accumulation in the liver.

Carbohydrate Detection and Lectin Isolation from Tegumental Tissue of Fasciola hepatica

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MB Molaei Rad

2010-02-01

Full Text Available "nBackground: Fascioliasis is a chronic hepatic disease and may be resulted from mechani­cal/molecular parasite adhesion to host liver tissue. The aim of this study was to detect surface car­bohydrate and lectin, carbohydrate-binding protein isolation that might be responsible of this molecular binding."nMethods: The present experimental work was conducted in the Department of Medical Parasitol­ogy and Mycology, School of Public Health, Tehran University of Medical Sciences, Te­hran, Iran.  Fasciola hepatica parasites were collected from abattoir (Saman, Tehran, Iran and surface mannose-carbohydrate was detected by fluorescein isothiocyanate (FITC conju­gated lectin (Lentil. Lectin of tegumental tissue from F. hepatica was isolated by affinity chroma­tography and detected by sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE."nResults: Mannose carbohydrate was observed on the surface of tegumental tissue from para­site under fluorescence microscope. Carbohydrate-binding protein or lectin with MW of 50 kDa also was isolated from homogenized tegument of helminth."nConclusion: These results are important for understanding of molecular pathogenesis of F. hepat­ica at the chronic phase of fascioliasis

A low-carbohydrate/high-fat diet improves glucoregulation in type 2 diabetes mellitus by reducing postabsorptive glycogenolysis.

Science.gov (United States)

Allick, Gideon; Bisschop, Peter H; Ackermans, Mariette T; Endert, Erik; Meijer, Alfred J; Kuipers, Folkert; Sauerwein, Hans P; Romijn, Johannes A

2004-12-01

The aim of this study was to examine the mechanisms by which dietary carbohydrate and fat modulate fasting glycemia. We compared the effects of an eucaloric high-carbohydrate (89% carbohydrate) and high-fat (89% fat) diet on fasting glucose metabolism and insulin sensitivity in seven obese patients with type 2 diabetes using stable isotopes and euglycemic hyperinsulinemic clamps. At basal insulin levels glucose concentrations were 148 +/- 11 and 123 +/- 11 mg/dl (8.2 +/- 0.6 and 6.8 +/- 0.6 mmol/liter) on the high-carbohydrate and high-fat diet, respectively (P carbohydrate diet (1.88 +/- 0.06 vs. 1.55 +/- 0.05 mg/kg.min (10.44 +/- 0.33 vs. 8.61 +/- 0.28 micromol/kg.min) (P carbohydrate and high-fat diet, respectively. We conclude that short-term variations in dietary carbohydrate to fat ratios affect basal glucose metabolism in people with type 2 diabetes merely through modulation of the rate of glycogenolysis, without affecting insulin sensitivity of glucose metabolism.

MBTH: A novel approach to rapid, spectrophotometric quantitation of total algal carbohydrates.

Science.gov (United States)

Van Wychen, Stefanie; Long, William; Black, Stuart K; Laurens, Lieve M L

2017-02-01

A high-throughput and robust application of the 3-methyl-2-benzothiazolinone hydrazone (MBTH) method was developed for carbohydrate determination in microalgae. The traditional phenol-sulfuric acid method to quantify carbohydrates is strongly affected by algal biochemical components and exhibits a highly variable response to microalgal monosaccharides. We present a novel use of the MBTH method to accurately quantify carbohydrates in hydrolyzate after acid hydrolysis of algal biomass, without a need for neutralization. The MBTH method demonstrated consistent and sensitive quantitation of algae-specific monosaccharides down to 5 μg mL -1 without interference from other algae acidic hydrolyzate components. Copyright © 2016 Elsevier Inc. All rights reserved.

Aliphatic, cyclic, and aromatic organic acids, vitamins, and carbohydrates in soil: a review.

Science.gov (United States)

Vranova, Valerie; Rejsek, Klement; Formanek, Pavel

2013-11-10

Organic acids, vitamins, and carbohydrates represent important organic compounds in soil. Aliphatic, cyclic, and aromatic organic acids play important roles in rhizosphere ecology, pedogenesis, food-web interactions, and decontamination of sites polluted by heavy metals and organic pollutants. Carbohydrates in soils can be used to estimate changes of soil organic matter due to management practices, whereas vitamins may play an important role in soil biological and biochemical processes. The aim of this work is to review current knowledge on aliphatic, cyclic, and aromatic organic acids, vitamins, and carbohydrates in soil and to identify directions for future research. Assessments of organic acids (aliphatic, cyclic, and aromatic) and carbohydrates, including their behaviour, have been reported in many works. However, knowledge on the occurrence and behaviour of D-enantiomers of organic acids, which may be abundant in soil, is currently lacking. Also, identification of the impact and mechanisms of environmental factors, such as soil water content, on carbohydrate status within soil organic matter remains to be determined. Finally, the occurrence of vitamins in soil and their role in biological and biochemical soil processes represent an important direction for future research.

Aliphatic, Cyclic, and Aromatic Organic Acids, Vitamins, and Carbohydrates in Soil: A Review

Directory of Open Access Journals (Sweden)

Valerie Vranova

2013-01-01

Full Text Available Organic acids, vitamins, and carbohydrates represent important organic compounds in soil. Aliphatic, cyclic, and aromatic organic acids play important roles in rhizosphere ecology, pedogenesis, food-web interactions, and decontamination of sites polluted by heavy metals and organic pollutants. Carbohydrates in soils can be used to estimate changes of soil organic matter due to management practices, whereas vitamins may play an important role in soil biological and biochemical processes. The aim of this work is to review current knowledge on aliphatic, cyclic, and aromatic organic acids, vitamins, and carbohydrates in soil and to identify directions for future research. Assessments of organic acids (aliphatic, cyclic, and aromatic and carbohydrates, including their behaviour, have been reported in many works. However, knowledge on the occurrence and behaviour of D-enantiomers of organic acids, which may be abundant in soil, is currently lacking. Also, identification of the impact and mechanisms of environmental factors, such as soil water content, on carbohydrate status within soil organic matter remains to be determined. Finally, the occurrence of vitamins in soil and their role in biological and biochemical soil processes represent an important direction for future research.

Flight metabolism in Panstrongylus megistus (Hemiptera: Reduviidae): the role of carbohydrates and lipids.

Science.gov (United States)

Canavoso, Lilián E; Stariolo, Raúl; Rubiolo, Edilberto R

2003-10-01

The metabolism of lipids and carbohydrates related to flight activity in Panstrongylus megistus was investigated. Insects were subjected to different times of flight under laboratory conditions and changes in total lipids, lipophorin density and carbohydrates were followed in the hemolymph. Lipids and glycogen were also assayed in fat body and flight muscle. In resting insects, hemolymph lipids averaged 3.4 mg/ml and significantly increased after 45 min of flight (8.8 mg/ml, P < 0.001). High-density lipophorin was the sole lipoprotein observed in resting animals. A second fraction with lower density corresponding to low-density lipophorin appeared in insects subjected to flight. Particles from both fractions showed significant differences in diacylglycerol content and size. In resting insects, carbohydrate levels averaged 0.52 mg/ml. They sharply declined more than twofold after 15 min of flight, being undetectable in hemolymph of insects flown for 45 min. Lipid and glycogen from fat body and flight muscle decreased significantly after 45 min of flight. Taken together, the results indicate that P. megistus uses carbohydrates during the initiation of the flight after which, switching fuel for flight from carbohydrates to lipids.

Flight metabolism in Panstrongylus megistus (Hemiptera: Reduviidae: the role of carbohydrates and lipids

Directory of Open Access Journals (Sweden)

Lilián E Canavoso

2003-10-01

Full Text Available The metabolism of lipids and carbohydrates related to flight activity in Panstrongylus megistus was investigated. Insects were subjected to different times of flight under laboratory conditions and changes in total lipids, lipophorin density and carbohydrates were followed in the hemolymph. Lipids and glycogen were also assayed in fat body and flight muscle. In resting insects, hemolymph lipids averaged 3.4 mg/ml and significantly increased after 45 min of flight (8.8 mg/ml, P < 0.001. High-density lipophorin was the sole lipoprotein observed in resting animals. A second fraction with lower density corresponding to low-density lipophorin appeared in insects subjected to flight. Particles from both fractions showed significant differences in diacylglycerol content and size. In resting insects, carbohydrate levels averaged 0.52 mg/ml. They sharply declined more than twofold after 15 min of flight, being undetectable in hemolymph of insects flown for 45 min. Lipid and glycogen from fat body and flight muscle decreased significantly after 45 min of flight. Taken together, the results indicate that P. megistus uses carbohydrates during the initiation of the flight after which, switching fuel for flight from carbohydrates to lipids.

Aliphatic, Cyclic, and Aromatic Organic Acids, Vitamins, and Carbohydrates in Soil: A Review

Science.gov (United States)

Vranova, Valerie; Rejsek, Klement; Formanek, Pavel

2013-01-01

Organic acids, vitamins, and carbohydrates represent important organic compounds in soil. Aliphatic, cyclic, and aromatic organic acids play important roles in rhizosphere ecology, pedogenesis, food-web interactions, and decontamination of sites polluted by heavy metals and organic pollutants. Carbohydrates in soils can be used to estimate changes of soil organic matter due to management practices, whereas vitamins may play an important role in soil biological and biochemical processes. The aim of this work is to review current knowledge on aliphatic, cyclic, and aromatic organic acids, vitamins, and carbohydrates in soil and to identify directions for future research. Assessments of organic acids (aliphatic, cyclic, and aromatic) and carbohydrates, including their behaviour, have been reported in many works. However, knowledge on the occurrence and behaviour of D-enantiomers of organic acids, which may be abundant in soil, is currently lacking. Also, identification of the impact and mechanisms of environmental factors, such as soil water content, on carbohydrate status within soil organic matter remains to be determined. Finally, the occurrence of vitamins in soil and their role in biological and biochemical soil processes represent an important direction for future research. PMID:24319374

Renewable carbohydrates are a potential high-density hydrogen carrier

Energy Technology Data Exchange (ETDEWEB)

Zhang, Y.-H. Percival [Biological Systems Engineering Department, 210-A Seitz Hall, Virginia Polytechnic Institute and State University, Blacksburg, VA 24061 (United States); Institute for Critical Technology and Applied Sciences (ICTAS), Virginia Polytechnic Institute and State University, Blacksburg, VA 24061 (United States); DOE BioEnergy Science Center (BESC), Oak Ridge, TN 37831 (United States)

2010-10-15

The possibility of using renewable biomass carbohydrates as a potential high-density hydrogen carrier is discussed here. Gravimetric density of polysaccharides is 14.8 H{sub 2} mass% where water can be recycled from PEM fuel cells or 8.33% H{sub 2} mass% without water recycling; volumetric densities of polysaccharides are >100 kg of H{sup 2}/m{sup 3}. Renewable carbohydrates (e.g., cellulosic materials and starch) are less expensive based on GJ than are other hydrogen carriers, such as hydrocarbons, biodiesel, methanol, ethanol, and ammonia. Biotransformation of carbohydrates to hydrogen by cell-free synthetic (enzymatic) pathway biotransformation (SyPaB) has numerous advantages, such as high product yield (12 H{sub 2}/glucose unit), 100% selectivity, high energy conversion efficiency (122%, based on combustion energy), high-purity hydrogen generated, mild reaction conditions, low-cost of bioreactor, few safety concerns, and nearly no toxicity hazards. Although SyPaB may suffer from current low reaction rates, numerous approaches for accelerating hydrogen production rates are proposed and discussed. Potential applications of carbohydrate-based hydrogen/electricity generation would include hydrogen bioreactors, home-size electricity generators, sugar batteries for portable electronics, sugar-powered passenger vehicles, and so on. Developments in thermostable enzymes as standardized building blocks for cell-free SyPaB projects, use of stable and low-cost biomimetic NAD cofactors, and accelerating reaction rates are among the top research and development priorities. International collaborations are urgently needed to solve the above obstacles within a short time. (author)

Seasonal dynamics and age of stemwood nonstructural carbohydrates in temperate forest trees

Science.gov (United States)

Andrew D. Richardson; Mariah S. Carbone; Trevor F. Keenan; Claudia I. Czimczik; David Y. Hollinger; Paula Murakami; Paul G. Schaberg; Xiaomei. Xu

2013-01-01

Nonstructural carbohydrate reserves support tree metabolism and growth when current photosynthates are insufficient, offering resilience in times of stress. We monitored stemwood nonstructural carbohydrate (starch and sugars) concentrations of the dominant tree species at three sites in the northeastern United States. We estimated the mean age of the starch and sugars...

Mutagenicity of quaternary ammonium salts containing carbohydrate moieties

Energy Technology Data Exchange (ETDEWEB)

Dmochowska, Barbara [Department of Carbohydrate Chemistry, University of Gdansk, Sobieskiego 18, 80-952 Gdansk (Poland); Piosik, Jacek; Woziwodzka, Anna [Intercollegiate Faculty of Biotechnology, University of Gdansk and Medical University of Gdansk, Kladki 24, 80-822 Gdansk (Poland); Sikora, Karol; Wisniewski, Andrzej [Department of Carbohydrate Chemistry, University of Gdansk, Sobieskiego 18, 80-952 Gdansk (Poland); Wegrzyn, Grzegorz, E-mail: wegrzyn@biotech.univ.gda.pl [Department of Molecular Biology, University of Gdansk, Kladki 24, 80-822 Gdansk (Poland)

2011-10-15

Highlights: {yields} A series of quaternary ammonium salts containing carbohydrate moieties, with configuration D-galacto, D-gluco and D-manno, was synthesized and characterized. {yields} The quaternary ammonium salts containing carbohydrate moieties revealed potent mutagenic activities, as assessed by using the Vibrio harveyi bioluminescence mutagenicity test. {yields} The N-[2-(D-glycopyranosyloxy)ethyl]-N,N,N-trimethylaminium salts were of the highest activity in the mutagenicity assay. {yields} We suggest that quaternary ammonium salts may be more hazardous than previously supposed. - Abstract: Quaternary ammonium salts are widely used in industrial, agricultural, healthcare and domestic applications. They are believed to be safe compounds, with little or no health hazard to humans. However, in this report, we demonstrate that a series of newly synthesized quaternary ammonium salts containing carbohydrate moieties reveal potent mutagenic activities, as assessed by using the Vibrio harveyi bioluminescence mutagenicity test. D-Gluco- and D-galacto-derivatives were found to have a higher mutagenic potential than D-manno-derivatives. Among the former groups of compounds, the N-[2-(D-glycopyranosyloxy)ethyl]-N,N,N-trimethylaminium salts were of the highest activity in the mutagenicity assay. These results suggest that the safety of quaternary ammonium salts may be lower than previously supposed, indicating a need for testing such compounds for their mutagenicity.

Mutagenicity of quaternary ammonium salts containing carbohydrate moieties

International Nuclear Information System (INIS)

Dmochowska, Barbara; Piosik, Jacek; Woziwodzka, Anna; Sikora, Karol; Wisniewski, Andrzej; Wegrzyn, Grzegorz

2011-01-01

Highlights: → A series of quaternary ammonium salts containing carbohydrate moieties, with configuration D-galacto, D-gluco and D-manno, was synthesized and characterized. → The quaternary ammonium salts containing carbohydrate moieties revealed potent mutagenic activities, as assessed by using the Vibrio harveyi bioluminescence mutagenicity test. → The N-[2-(D-glycopyranosyloxy)ethyl]-N,N,N-trimethylaminium salts were of the highest activity in the mutagenicity assay. → We suggest that quaternary ammonium salts may be more hazardous than previously supposed. - Abstract: Quaternary ammonium salts are widely used in industrial, agricultural, healthcare and domestic applications. They are believed to be safe compounds, with little or no health hazard to humans. However, in this report, we demonstrate that a series of newly synthesized quaternary ammonium salts containing carbohydrate moieties reveal potent mutagenic activities, as assessed by using the Vibrio harveyi bioluminescence mutagenicity test. D-Gluco- and D-galacto-derivatives were found to have a higher mutagenic potential than D-manno-derivatives. Among the former groups of compounds, the N-[2-(D-glycopyranosyloxy)ethyl]-N,N,N-trimethylaminium salts were of the highest activity in the mutagenicity assay. These results suggest that the safety of quaternary ammonium salts may be lower than previously supposed, indicating a need for testing such compounds for their mutagenicity.

The relationship between carbohydrate content and gamma irradiation during rooting of chrysanthemum cuttings

International Nuclear Information System (INIS)

Noh, Seol Ah; Kim, Jin Kyu

2003-01-01

The effect of gamma radiation on carbohydrate metabolism was studied in chrysanthemum cuttings. Total water-soluble carbohydrate, glucose, fructose, sucrose, and starch contents were measured in leaves and stems. Differences in the accumulation of carbohydrate associated with inhibition or stimulation in response to gamma irradiation. Sucrose levels increased significantly in leaves and stems until the 15th day, reaching maximum values on that day. Glucose contents declined rapidly until the 10th day and increased later, reaching maximum values on the 15th day. Fructose levels gradually increased, reaching maximum values at the 10th day, and then decreased again. Differences in the components of soluble carbohydrates were evident between rooting durations and doses. Soluble sugars were in the highest contents in the 20 Gy irradiated group. However, irradiation dose higher than 20 Gy resulted in an inhibitory effect

Characterization of the carbohydrate components of Taenia solium oncosphere proteins and their role in the antigenicity.

Science.gov (United States)

Arana, Yanina; Verastegui, Manuela; Tuero, Iskra; Grandjean, Louis; Garcia, Hector H; Gilman, Robert H

2013-10-01

This study examines the carbohydrate composition of Taenia solium whole oncosphere antigens (WOAs), in order to improve the understanding of the antigenicity of the T. solium. Better knowledge of oncosphere antigens is crucial to accurately diagnose previous exposure to T. solium eggs and thus predict the development of neurocysticercosis. A set of seven lectins conjugates with wide carbohydrate specificity were used on parasite fixations and somatic extracts. Lectin fluorescence revealed that D-mannose, D-glucose, D-galactose and N-acetyl-D-galactosamine residues were the most abundant constituents of carbohydrate chains on the surface of T. solium oncosphere. Lectin blotting showed that posttranslational modification with N-glycosylation was abundant while little evidence of O-linked carbohydrates was observed. Chemical oxidation and enzymatic deglycosylation in situ were performed to investigate the immunoreactivity of the carbohydrate moieties. Linearizing or removing the carbohydrate moieties from the protein backbones did not diminish the immunoreactivity of these antigens, suggesting that a substantial part of the host immune response against T. solium oncosphere is directed against the peptide epitopes on the parasite antigens. Finally, using carbohydrate probes, we demonstrated for the first time that the presence of several lectins on the surface of the oncosphere was specific to carbohydrates found in intestinal mucus, suggesting a possible role in initial attachment of the parasite to host cells.

Photosynthesis down-regulation precedes carbohydrate accumulation under sink limitation in Citrus.

Science.gov (United States)

Nebauer, Sergio G; Renau-Morata, Begoña; Guardiola, José Luis; Molina, Rosa-Victoria

2011-02-01

Photosynthesis down-regulation due to an imbalance between sources and sinks in Citrus leaves could be mediated by excessive accumulation of carbohydrates. However, there is limited understanding of the physiological role of soluble and insoluble carbohydrates in photosynthesis regulation and the elements triggering the down-regulation process. In this work, the role of non-structural carbohydrates in the regulation of photosynthesis under a broad spectrum of source-sink relationships has been investigated in the Salustiana sweet orange. Soluble sugar and starch accumulation in leaves, induced by girdling experiments, did not induce down-regulation of the photosynthetic rate in the presence of sinks (fruits). The leaf-to-fruit ratio did not modulate photosynthesis but allocation of photoassimilates to the fruits. The lack of strong sink activity led to a decrease in the photosynthetic rate and starch accumulation in leaves. However, photosynthesis down-regulation due to an excess of total soluble sugars or starch was discarded because photosynthesis and stomatal conductance reduction occurred prior to any significant accumulation of these carbohydrates. Gas exchange and fluorescence parameters suggested biochemical limitations to photosynthesis. In addition, the expression of carbon metabolism-related genes was altered within 24 h when strong sinks were removed. Sucrose synthesis and export genes were inhibited, whereas the expression of ADP-glucose pyrophosphorylase was increased to cope with the excess of assimilates. In conclusion, changes in starch and soluble sugar turnover, but not sugar content per se, could provide the signal for photosynthesis regulation. In these conditions, non-stomatal limitations strongly inhibited the photosynthetic rate prior to any significant increase in carbohydrate levels.

Effects of Changing the Amount and Source of Dietary Carbohydrates on Symptoms and Dietary Satisfaction Over a 1-Year Period in Subjects with Type 2 Diabetes: Canadian Trial of Carbohydrates in Diabetes (CCD).

Science.gov (United States)

Wolever, Thomas M S; Chiasson, Jean-Louis; Josse, Robert G; Leiter, Lawrence A; Maheux, Pierre; Rabasa-Lhoret, Rémi; Rodger, N Wilson; Ryan, Edmond A

2017-04-01

To determine the long-term effects of changing the amount or source of dietary carbohydrate on quality of life (QOL), symptoms and dietary satisfaction in people with type 2 diabetes. Subjects with diabetes treated by diet alone (n=162) were randomly assigned to high-carbohydrate/high-glycemic-index (HGI) diets; high-carbohydrate/low-glycemic-index (LGI) diets; or lower-carbohydrate/high-monounsaturated-fat (LC) diets for 1 year. We measured QOL at baseline and at study's end, and we measured symptoms and dietary satisfaction quarterly. The HGI, LGI and LC diets contained, respectively, 47±1, 52±1 and 40±1% energy carbohydrate; 30±1, 27±1 and 40±1% fat with GI 64±0.4, 55±0.4 and 59±0.4. Significantly more participants reported increased flatulence on LGI than on LC and HGI diets at 3 months (41%, 19%, 14%; pvs. 14%, 19%; pvs. 22%, 23%; pcarbohydrate diet than on the 50% carbohydrate diet, the LGI diet was no less satisfying than the HGI diet. Changes in appetite and dietary satisfaction may influence body weight and glycemic control, or vice-versa. Copyright © 2016 Canadian Diabetes Association. Published by Elsevier Inc. All rights reserved.

Development of Defatted Soy Flour-Based Adhesives by Acid Hydrolysis of Carbohydrates

Directory of Open Access Journals (Sweden)

Peitao Zheng

2017-04-01

Full Text Available Soy-based adhesives are attracting increasing attention in recent years because they are a renewable and environmentally friendly raw material. Defatted soy flour (DSF, comprised of 50% protein and 40% carbohydrate, is the most widely used raw material for the preparation of soy-based adhesives that are unfortunately hampered by poor gluability and water resistance. In the present study, we developed a self-crosslinking approach to prepare a formaldehyde-free defatted soy flour-based adhesive (SBA. Carbohydrates in the DSF were hydrolyzed with 0% (controls, 0.5%, 1.0%, 2.0%, 3.0% and 5.0% hydrochloric acid, and cross-linked with proteins to prepare the SBA. The effect of hydrolyzed carbohydrates on the performance of the SBA was investigated, and hydrolyzed carbohydrates significantly increased the amount of reducing sugars, but decreased insoluble substances. Fourier transform infrared spectroscopy (FTIR and X-ray photoelectron spectroscopy (XPS analyses revealed an enhanced cross-linking structure with fewer hydrophilic groups in cured SBAs. Maillard reactions between hydrolyzed carbohydrates and proteins resulted in SBAs with better gluability, rheological properties and thermal stability than controls. Scanning electron microscopy (SEM images showed that plywood bonded with SBA had a higher wood failure rate than controls. This approach has potential for preparing bio-adhesives with enhanced properties from other natural resources with a similar polysaccharides and protein composition.

Stacking interactions between carbohydrate and protein quantified by combination of theoretical and experimental methods.

Directory of Open Access Journals (Sweden)

Michaela Wimmerová

Full Text Available Carbohydrate-receptor interactions are an integral part of biological events. They play an important role in many cellular processes, such as cell-cell adhesion, cell differentiation and in-cell signaling. Carbohydrates can interact with a receptor by using several types of intermolecular interactions. One of the most important is the interaction of a carbohydrate's apolar part with aromatic amino acid residues, known as dispersion interaction or CH/π interaction. In the study presented here, we attempted for the first time to quantify how the CH/π interaction contributes to a more general carbohydrate-protein interaction. We used a combined experimental approach, creating single and double point mutants with high level computational methods, and applied both to Ralstonia solanacearum (RSL lectin complexes with α-L-Me-fucoside. Experimentally measured binding affinities were compared with computed carbohydrate-aromatic amino acid residue interaction energies. Experimental binding affinities for the RSL wild type, phenylalanine and alanine mutants were -8.5, -7.1 and -4.1 kcal x mol(-1, respectively. These affinities agree with the computed dispersion interaction energy between carbohydrate and aromatic amino acid residues for RSL wild type and phenylalanine, with values -8.8, -7.9 kcal x mol(-1, excluding the alanine mutant where the interaction energy was -0.9 kcal x mol(-1. Molecular dynamics simulations show that discrepancy can be caused by creation of a new hydrogen bond between the α-L-Me-fucoside and RSL. Observed results suggest that in this and similar cases the carbohydrate-receptor interaction can be driven mainly by a dispersion interaction.

Action of ionizing radiation on the carbohydrate metabolism enzymes

International Nuclear Information System (INIS)

Cherkasova, L.S.; Mironova, T.M.

1976-01-01

It follows from data reported in literature and those obtained in our laboratory that ionizing radiation does not drastically change the activity of enzymes of the carbohydrate metabolism in tissues of an animal organism. The data are reported on the effect of a whole-body single, fractionated or continuous irradiation of the enzymes of carbohydrate metabolism and the accompanying interrelated co-operative redistributions within the processes of aerobic and anaerobic glycolysis, and the pentose route of their conversion. The dependence of the postirradiation changes in the activity of enzymes on the neuroendocrine system response to irradiation has been demonstrated

Nutrition to Support Recovery from Endurance Exercise: Optimal Carbohydrate and Protein Replacement.

Science.gov (United States)

Moore, Daniel R

2015-01-01

Proper nutrition is vital to optimize recovery after endurance exercise. Dietary carbohydrate and protein provide the requisite substrates to enhance glycogen resynthesis and remodel skeletal muscle proteins, respectively, both of which would be important to rapidly restore muscle function and performance. With short recovery windows (optimal ingestion of both carbohydrate and protein.

Structural analysis of the carbohydrate chains of glycoproteins by 500-MHz 1H-NMR spectroscopy

International Nuclear Information System (INIS)

Mutsaers, J.H.G.M.

1986-01-01

This thesis deals with the structural analysis by 500-MHz 1 H-NMR spectroscopy of carbohydrate chains obtained from glycoproteins. In the chapters 1 to 6 the structural analysis of N-glycosidically linked carbohydrate chains is described. The chapters 7 to 10 describe the structural analysis of O-glycosidically linked carbohydrate chains. 381 refs.; 44 figs.; 24 tabs.; 7 schemes

Regional variations of cell surface carbohydrates in human oral stratified epithelium

DEFF Research Database (Denmark)

Vedtofte, P; Dabelsteen, Erik; Hakomori, S

1984-01-01

The distribution of blood group carbohydrate chains with antigen A, B, H type 2 chain (A and B precursor), and N-acetyllactosamine (H type 2 precursor) specificity was studied in human oral epithelium from different anatomical regions. These represented various epithelial differentiation patterns...... epithelium from nine blood group A, two blood group B, and nine blood group O individuals. The blood group carbohydrate chains were examined in tissue sections by immunofluorescence microscopy. The A and B blood group antigens were detected by human blood group sera, and antigen H type 2 chains and N...... antigen H type 2 chains in metaplastically keratinized buccal epithelium was found to differ significantly from that seen in normal non-keratinized buccal epithelium. The regional variations demonstrated in cell surface carbohydrates are suggested to reflect differences in tissue differentiation....

Dissolved carbohydrate in the central Arabian Sea

Digital Repository Service at National Institute of Oceanography (India)

Dhople, V.M.; Bhosle, N.B.

with chlorophyll a (P 0.001) and phaeopigments (P 0.001) suggesting its release from the former and zooplankton grazing in the latter. Inverse correlations with dissolved oxygen, phosphate and nitrate indicated the possibility of the release of carbohydrate from...

A new versatile microarray-based method for high-throughput screening of carbohydrate-active enzymes

DEFF Research Database (Denmark)

Vidal Melgosa, Silvia; Pedersen, Henriette Lodberg; Schückel, Julia

2015-01-01

Carbohydrate-active enzymes have multiple biological roles and industrial applications. Advances in genome and transcriptome sequencing, together with associated bioinformatic tools have identified vast numbers of putative carbohydrate degrading and modifying enzymes including glycoside hydrolases...... that the technique can be used to analyse both endo-acting and exo-acting glycoside hydrolases, polysaccharide lyases, carbohydrate esterases and lytic polysaccharide monooxygenases. We demonstrate the potential of the technique by identifying the substrate specificities of purified un-characterised enzymes...

Distributions and seasonal variations of dissolved carbohydrates in the Jiaozhou Bay, China

Science.gov (United States)

Yang, Gui-Peng; Zhang, Yan-Ping; Lu, Xiao-Lan; Ding, Hai-Bing

2010-06-01

Surface seawater samples were collected in the Jiaozhou Bay, a typical semi-closed basin located at the western part of the Shandong Peninsula, China, during four cruises. Concentrations of monosaccharides (MCHO), polysaccharides (PCHO) and total dissolved carbohydrates (TCHO) were measured with the 2,4,6-tripyridyl- s-triazine spectroscopic method. Concentrations of TCHO varied from 10.8 to 276.1 μM C for all samples and the ratios of TCHO to dissolved organic carbon (DOC) ranged from 1.1 to 67.9% with an average of 10.1%. This result indicated that dissolved carbohydrates were an important constituent of DOC in the surface seawater of the Jiaozhou Bay. In all samples, the concentrations of MCHO ranged from 2.9 to 65.9 μM C, comprising 46.1 ± 16.6% of TCHO on average, while PCHO ranged from 0.3 to 210.2 μM C, comprising 53.9 ± 16.6% of TCHO on average. As a major part of dissolved carbohydrates, the concentrations of PCHO were higher than those of MCHO. MCHO and PCHO accumulated in January and July, with minimum average concentration in April. The seasonal variation in the ratios of TCHO to DOC was related to water temperature, with high values in January and low values in July and October. The concentrations of dissolved carbohydrates displayed a decreasing trend from the coastal to the central areas. Negative correlations between concentrations of TCHO and salinity in July suggested that riverine input around the Jiaozhou Bay had an important effect on the concentrations of dissolved carbohydrates in surface seawater. The pattern of distributions of MCHO and PCHO reported in this study added to the global picture of dissolved carbohydrates distribution.

Characterization of protein and carbohydrate mid-IR spectral features in crop residues

Science.gov (United States)

Xin, Hangshu; Zhang, Yonggen; Wang, Mingjun; Li, Zhongyu; Wang, Zhibo; Yu, Peiqiang

2014-08-01

To the best of our knowledge, a few studies have been conducted on inherent structure spectral traits related to biopolymers of crop residues. The objective of this study was to characterize protein and carbohydrate structure spectral features of three field crop residues (rice straw, wheat straw and millet straw) in comparison with two crop vines (peanut vine and pea vine) by using Fourier transform infrared spectroscopy (FTIR) technique with attenuated total reflectance (ATR). Also, multivariate analyses were performed on spectral data sets within the regions mainly related to protein and carbohydrate in this study. The results showed that spectral differences existed in mid-IR peak intensities that are mainly related to protein and carbohydrate among these crop residue samples. With regard to protein spectral profile, peanut vine showed the greatest mid-IR band intensities that are related to protein amide and protein secondary structures, followed by pea vine and the rest three field crop straws. The crop vines had 48-134% higher spectral band intensity than the grain straws in spectral features associated with protein. Similar trends were also found in the bands that are mainly related to structural carbohydrates (such as cellulosic compounds). However, the field crop residues had higher peak intensity in total carbohydrates region than the crop vines. Furthermore, spectral ratios varied among the residue samples, indicating that these five crop residues had different internal structural conformation. However, multivariate spectral analyses showed that structural similarities still exhibited among crop residues in the regions associated with protein biopolymers and carbohydrate. Further study is needed to find out whether there is any relationship between spectroscopic information and nutrition supply in various kinds of crop residue when fed to animals.

Distribution of particulate carbohydrate in the eastern Arabian sea along 15 (degrees) N

Digital Repository Service at National Institute of Oceanography (India)

Nandakumar, K.; Bhosle, N.B.; Wagh, A.B.

The concentration of particulate carbohydrate varied from 38-158 mu g.l-1 and 19-239 mu g.l-1 in shelf and slope waters respectively. At 10 m water column the concentration of particulate carbohydrate increased with the distance from the shore...

Effects of Watering and Fertilization on Carbohydrate Reserves in Sugar Maple Seedlings

Science.gov (United States)

Clayton M., Jr. Carl; John R. Donnelly; Boyd W. Post

1978-01-01

Sugar maple seedlings, grown under three nutrient and three moisture levels, were analyzed after three growing seasons for starch and ethanol-soluble sugars. Analytical procedures are detailed in the appendix. Fertilization did not affect carbohydrate levels in stems or roots. Water stress caused a significant reduction in the amount of carbohydrates in stems and roots...

Weight Loss at a Cost: Implications of High-Protein, Low- Carbohydrate Diets.

Science.gov (United States)

Gabel, Kathe A.; Lund, Robin J.

2002-01-01

Addresses three claims of high-protein, low-carbohydrate diets: weight loss is attributed to the composition of the diet; insulin promotes the storage of fat, thereby, by limiting carbohydrates, dieters will decrease levels of insulin and body fat; and weight loss is the result of fat loss. The paper examines relevant scientific reports and notes…

One-Pot Conversion of Carbohydrates into Furan Derivatives via Furfural and 5-Hydroxylmethylfurfural as Intermediates.

Science.gov (United States)

Liu, Bing; Zhang, Zehui

2016-08-23

Recently, there has been growing interest in the transformation of renewable biomass into value-added fuels and chemicals. The catalytic conversion of naturally abundant carbohydrates can generate two-important furan chemicals: 5-hydroxymethylfurfural (HMF) from C6 carbohydrates and furfural from C5 carbohydrates. Both HMF and furfural have received great interest as precursors in the synthesis of commodity chemicals and liquid fuels. In recent years, a trend has emerged to integrate sequential catalytic processes involving multistep reactions for the direct one-pot transformation of carbohydrates into the aimed fuels and chemicals. One-pot reactions have remarkably unique and environmentally friendly benefits, including the fact that isolation and purification of intermediate compounds can be avoided. Herein, the present article aims to review recent advances in the one-pot conversion of carbohydrates into furan derivatives via furfural and HMF as intermediates. Special attention will be paid to the catalytic systems, mechanistic insight, reaction pathways, and catalyst stability. It is expected that this review will guide researchers to develop effective catalytic systems for the one-pot transformation of carbohydrates into furan derivatives. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Effects of perinatal hypothyroidism in the carbohydrate composition of cochlear tectorial membrane.

Science.gov (United States)

Gil-Loyzaga, P; Bueno, A M; Broto, J P; Pérez, A M

1990-04-01

The presence of carbohydrates in the cochlear tectorial membrane (TM) of normal and hypothyroid rats was analyzed using fluorescent lectin probes. SBA and WGA lectins exhibited a similar reactivity in both normal and hypothyroid TMs. DBA, RCA1, UEA1 and Con A lectins were also reactive, although they showed a different distribution pattern between normal and hypothyroid TMs. Lastly, one of the lectins, PNA, was only labeled in hypothyroid TMs. These findings suggest that carbohydrate chains containing residues of N-acetyl-D-galactosamine (GalNAc) and N-acetyl-D-glucosamine, are similarly distributed in normal and hypothyroid TMs. Other carbohydrate residues as GalNAc alpha 1,3 GalNAc, D-galactose (Gal), L-fucose and D-mannose, are present, but are abnormally distributed in hypothyroid TMs. The Gal beta 1,3GalNAc residues, recognized by PNA, could be present only in the hypothyroid TMs. Alterations in glycosylation of the glycoproteins in the hypothyroid TM could be responsible for the abnormal distribution pattern of carbohydrate residues here described, and for the distorted shape of the hypothyroid TM.

A Moderate Low-Carbohydrate Low-Calorie Diet Improves Lipid Profile, Insulin Sensitivity and Adiponectin Expression in Rats

Directory of Open Access Journals (Sweden)

Jie-Hua Chen

2015-06-01

Full Text Available Calorie restriction (CR via manipulating dietary carbohydrates has attracted increasing interest in the prevention and treatment of metabolic syndrome. There is little consensus about the extent of carbohydrate restriction to elicit optimal results in controlling metabolic parameters. Our study will identify a better carbohydrate-restricted diet using rat models. Rats were fed with one of the following diets for 12 weeks: Control diet, 80% energy (34% carbohydrate-reduced and 60% energy (68% carbohydrate-reduced of the control diet. Changes in metabolic parameters and expressions of adiponectin and peroxisome proliferator activator receptor γ (PPARγ were identified. Compared to the control diet, 68% carbohydrate-reduced diet led to a decrease in serum triglyceride and increases inlow density lipoprotein-cholesterol (LDL-C, high density lipoprotein-cholesterol (HDL-C and total cholesterol; a 34% carbohydrate-reduced diet resulted in a decrease in triglycerides and an increase in HDL-cholesterol, no changes however, were shown in LDL-cholesterol and total cholesterol; reductions in HOMA-IR were observed in both CR groups. Gene expressions of adiponectin and PPARγ in adipose tissues were found proportionally elevated with an increased degree of energy restriction. Our study for the first time ever identified that a moderate-carbohydrate restricted diet is not only effective in raising gene expressions of adiponectin and PPARγ which potentially lead to better metabolic conditions but is better at improving lipid profiles than a low-carbohydrate diet in rats.

Prediction of Pectin Yield and Quality by FTIR and Carbohydrate Microarray Analysis

DEFF Research Database (Denmark)

Baum, Andreas; Dominiak, Malgorzata Maria; Vidal-Melgosa, Silvia

2017-01-01

and carbohydrate microarray analysis were performed directly on the crude lime peel extracts during the time course of the extractions. Multivariate analysis of the data was carried out to predict final pectin yields. Fourier transform infrared spectroscopy (FTIR) was found applicable for determining the optimal...... extraction time for the enzymatic and acidic extraction processes, respectively. The combined results of FTIR and carbohydrate microarray analysis suggested major differences in the crude pectin extracts obtained by enzymatic and acid extraction, respectively. Enzymatically extracted pectin, thus, showed......, and that FTIR and carbohydrate microarray analysis have potential to be developed into online process analysis tools for prediction of pectin extraction yields and pectin features from measurements on crude pectin extracts....

Carbohydrates in diversity-oriented synthesis: challenges and opportunities.

Science.gov (United States)

Lenci, E; Menchi, G; Trabocchi, A

2016-01-21

Over the last decade, Diversity-Oriented Synthesis (DOS) has become a new paradigm for developing large collections of structurally diverse small molecules as probes to investigate biological pathways, and to provide a larger array of the chemical space. Drug discovery and chemical biology are taking advantage of DOS approaches to exploit highly-diverse and complex molecular platforms, producing advances in both target and ligand discovery. In this view, carbohydrates are attractive building blocks for DOS libraries, due to their stereochemical diversity and high density of polar functional groups, thus offering many possibilities for chemical manipulation and scaffold decoration. This review will discuss research contributions and perspectives on the application of carbohydrate chemistry to explore the accessible chemical space through appendage, stereochemical and scaffold diversity.

A critical review of low-carbohydrate diets in people with Type 2 diabetes.

Science.gov (United States)

van Wyk, H J; Davis, R E; Davies, J S

2016-02-01

The efficacy of low-carbohydrate diets (LCD) in people with Type 2 diabetes has divided the nutrition community. This review seeks to re-examine the available data to clarify understanding. A comprehensive search of databases was used to identify meta-analyses of LCD in Type 2 diabetes. To improve the quality of the studies analysed, the following inclusion criteria were applied: randomized control trials ≥ 4 weeks in people aged > 18 years with Type 2 diabetes; a carbohydrate intake ≤ 45% of total energy intake per day; and a dietary intake assessment at the end of the study. The resulting studies were subjected to a thematic analysis. Nine meta-analyses were identified containing 153 studies. Twelve studies met our amended inclusion criteria. There were no significant differences in metabolic markers, including glycaemic control, between the two diets, although weight loss with a LCD was greater in one study. Carbohydrate intake at 1 year in very LCD (diets was as little as 8 g/day of carbohydrates. Total energy intake remains the dietary predictor of body weight. A LCD appears no different from a high-carbohydrate diet in terms of metabolic markers and glycaemic control. Very LCDs may not be sustainable over a medium to longer term as carbohydrate intake in diets within studies often converged toward a more moderate level. The variable quality of studies included in earlier meta-analyses likely explains the previous inconsistent findings between meta-analyses. © 2015 The Authors. Diabetic Medicine © 2015 Diabetes UK.

Total hip arthroplasty and perioperative oral carbohydrate treatment: a randomised, double-blind, controlled trial.

Science.gov (United States)

Harsten, Andreas; Hjartarson, Hjörtur; Toksvig-Larsen, Sören

2012-06-01

Perioperative oral carbohydrate intake is beneficial to general surgery patients. Total hip arthroplasty is a common surgical procedure, and even a moderate improvement in patient outcome could have a significant effect on the resources needed for these patients. However, few studies have focused on the effects of carbohydrate intake on orthopaedic patients. The purpose of this study was to investigate if perioperative oral carbohydrate intake alters the postoperative course for patients undergoing total hip arthroplasty. The primary hypothesis was that pain scores would be lower in patients treated with carbohydrate. A randomised, double-blind, controlled trial. This study was carried out between September 2009 and April 2011 at a district Swedish hospital that specialises in orthopaedic surgery. Sixty ASA physical status I-III patients scheduled for elective total hip arthroplasty were included. Exclusion criteria were obesity, diabetes, prior hip surgery to the same hip, ongoing infection, immunological deficiency or age less than 50 or more than 80 years. Patients were given 400 ml of either an oral 12.5% carbohydrate solution or a placebo beverage (flavoured water) 1.5 h before and 2 h after surgery. Visual analogue scales were used to score six discomfort parameters. Immediately prior to surgery, the carbohydrate-treated patients were less hungry (median score 9.5 vs. 22 mm) and experienced less nausea (0 vs. 1.5 mm) (Phip arthroplasty.

Cell surface carbohydrate changes during embryonic and fetal skin development

DEFF Research Database (Denmark)

Dabelsteen, Erik; Holbrook, K; Clausen, H

1986-01-01

Monoclonal antibodies to four type 2 chain carbohydrate antigens were used for immunohistochemical studies of embryonic and fetal skin. The antibodies detected N-acetyllactosamine and 3 fucosyl substitutes of this, blood group antigen H, Lex, and Ley. Periderm consistently stained for N-acetyllac......Monoclonal antibodies to four type 2 chain carbohydrate antigens were used for immunohistochemical studies of embryonic and fetal skin. The antibodies detected N-acetyllactosamine and 3 fucosyl substitutes of this, blood group antigen H, Lex, and Ley. Periderm consistently stained for N...

Transporter’s evolution and carbohydrate metabolic clusters

NARCIS (Netherlands)

Plantinga, Titia H.; Does, Chris van der; Driessen, Arnold J.M.

2004-01-01

The yiaQRS genes of Escherichia coli K-12 are involved in carbohydrate metabolism. Clustering of homologous genes was found throughout several unrelated bacteria. Strikingly, all four bacterial transport protein classes were found, conserving transport function but not mechanism. It appears that

Biosynthesis of intestinal microvillar proteins. Processing of N-linked carbohydrate is not required for surface expression

DEFF Research Database (Denmark)

Danielsen, Erik Michael; Cowell, G M

1986-01-01

Castanospermine, an inhibitor of glucosidase I, the initial enzyme in the trimming of N-linked carbohydrate, was used to study the importance of carbohydrate processing in the biosynthesis of microvillar enzymes in organ-cultured pig intestinal explants. For aminopeptidase N (EC 3.4.11.2), aminop......Castanospermine, an inhibitor of glucosidase I, the initial enzyme in the trimming of N-linked carbohydrate, was used to study the importance of carbohydrate processing in the biosynthesis of microvillar enzymes in organ-cultured pig intestinal explants. For aminopeptidase N (EC 3...

Gastric emptying, glucose metabolism and gut hormones: evaluation of a common preoperative carbohydrate beverage.

Science.gov (United States)

Vermeulen, Mechteld A R; Richir, Milan C; Garretsen, Martijn K; van Schie, Annelies; Ghatei, Mohammed A; Holst, Jens J; Heijboer, Annemieke C; Uitdehaag, Bernard M J; Diamant, Michaela; Eekhoff, E Marelise W; van Leeuwen, Paul A M; Ligthart-Melis, Gerdien C

2011-09-01

To study the gastric-emptying rate and gut hormonal response of two carbohydrate-rich beverages. A specifically designed carbohydrate-rich beverage is currently used to support the surgical patient metabolically. Fruit-based beverages may also promote recovery, due to natural antioxidant and carbohydrate content. However, gastric emptying of fluids is influenced by its nutrient composition; hence, safety of preoperative carbohydrate loading should be confirmed. Because gut hormones link carbohydrate metabolism and gastric emptying, hormonal responses were studied. In eight volunteers, gastric emptying rates of both 400 mL of a ready-to-use beverage (A: Nutricia preOp; 50.4 g carbohydrates-mainly polysaccharides; 260 mOsm/kg) and 400 mL over-the-counter fruit-based lemonade (B: Roosvicee Original; 48 g carbohydrates--mainly fruit-associated saccharides; 805 mOsm/kg) were determined scintigraphically (using hepatate Tc-99(m)) according to a crossover design. Plasma glucose, insulin, C-peptide, glucagon-like peptide (GLP-1), peptide YY, total glucagon, and ghrelin were studied. Gastric emptying showed no differences in residual volumes. Earlier onset in emptying for beverage A versus B was observed (trend), with significantly higher glucose, insulin, C-peptide, and glucagon responses at 15-90 min. GLP-1 was inversely related to residual volume. Fruit-based lemonade is a safe alternative for preoperative purposes. It induces a more limited glucose, insulin, and C-peptide response. Later onset in gastric emptying (B versus A: trend), lower glucagon release, and differences in beverage content and osmolarity may have contributed to those differences. Efficient emptying was reflected by early GLP-1 levels. Copyright © 2011 Elsevier Inc. All rights reserved.

NIR calibration of soluble stem carbohydrates for predicting drought tolerance in spring wheat

Science.gov (United States)

Soluble stem carbohydrates are a component of drought response in wheat (Triticum aestivum L.) and other grasses. Near-infrared spectroscopy (NIR) can rapidly assay for soluble carbohydrates indirectly, but this requires a statistical model for calibration. The objectives of this study were: (i) to ...

Do asparagine-linked carbohydrate chains in glycoproteins have a preference for beta-bends?

NARCIS (Netherlands)

Beintema, Jaap J.

X-ray structures of the conformation of carbohydrate moieties and connected regions of glycoproteins are summarized. Evidence is presented that there is some preference for carbohydrate attachment at β-bends. Evolution may have favored glycosylation to occur at bends to ensure free mobility of the

Postharvest flower development in asiatic hybrid lilies as related to tepal carbohydrate status

NARCIS (Netherlands)

Meulen-Muisers, van der J.J.M.; Oeveren, van J.C.; Plas, van der L.H.W.; Tuyl, van J.M.

2001-01-01

For three Asiatic hybrid lily cultivars (‘Bright Beauty’, ‘Fashion’, ‘Orlito’) the potential postharvest performance of floral buds in terms of growth, anthesis and longevity was studied in relation to tepal carbohydrate status. To determine the importance of carbohydrate redistribution within lily

Synthetic Strategies for Converting Carbohydrates into Carbocycles by the Use of Olefin Metathesis

DEFF Research Database (Denmark)

Madsen, Robert

2007-01-01

This microreview covers recent advances in the use of ring-closing metathesis for the synthesis of carbocycles from carbohydrates. Various strategies for the synthesis of a,w-dienes from carbohydrates are presented, which give rise to a large variety of dienes with different stereochemistry, prot...

Comparative Studies on the Carbohydrate Composition of Marine Macroalgae: Final Technical Report

Energy Technology Data Exchange (ETDEWEB)

Mack, R. W.

1985-01-01

The purpose of this subcontract is to evaluate carbohydrates from macroalgae common to the Gulf of Mexico. Information from these analyses will be used to provide an indication of the feasibility of fermenting macroalgae to ethanol. Knowledge of the carbohydrates will allow for assessment of required pretreatments and utilization efficiencies in converting algal feedstocks to ethanol.

Carbohydrate regulation of photosynthesis and respiration from branch girdling in four species of wet tropical rain forest trees.

Science.gov (United States)

Asao, Shinichi; Ryan, Michael G

2015-06-01

How trees sense source-sink carbon balance remains unclear. One potential mechanism is a feedback from non-structural carbohydrates regulating photosynthesis and removing excess as waste respiration when the balance of photosynthesis against growth and metabolic activity changes. We tested this carbohydrate regulation of photosynthesis and respiration using branch girdling in four tree species in a wet tropical rainforest in Costa Rica. Because girdling severs phloem to stop carbohydrate export while leaving xylem intact to allow photosynthesis, we expected carbohydrates to accumulate in leaves to simulate a carbon imbalance. We varied girdling intensity by removing phloem in increments of one-quarter of the circumference (zero, one--quarter, half, three-quarters, full) and surrounded a target branch with fully girdled ones to create a gradient in leaf carbohydrate content. Light saturated photosynthesis rate was measured in situ, and foliar respiration rate and leaf carbohydrate content were measured after destructive harvest at the end of the treatment. Girdling intensity created no consistent or strong responses in leaf carbohydrates. Glucose and fructose slightly increased in all species by 3.4% per one-quarter girdle, total carbon content and leaf mass per area increased only in one species by 5.4 and 5.5% per one-quarter girdle, and starch did not change. Only full girdling lowered photosynthesis in three of four species by 59-69%, but the decrease in photosynthesis was unrelated to the increase in glucose and fructose content. Girdling did not affect respiration. The results suggest that leaf carbohydrate content remains relatively constant under carbon imbalance, and any changes are unlikely to regulate photosynthesis or respiration. Because girdling also stops the export of hormones and reactive oxygen species, girdling may induce physiological changes unrelated to carbohydrate accumulation and may not be an effective method to study carbohydrate feedback

Carbocyclic Carbohydrate Mimics as Potential Glycosidase Inhibitors

DEFF Research Database (Denmark)

Fanefjord, Mette; Lundt, Inge

It has been proven that aminocyclopentanols having the aminogroup adjacent to a carbon sidechain could be potential anomer-selective glycosidase inhibitors [1]. A successful pathway for synthesising mimics to L-carbohydrates 2, by introducing nitrogen to the C6 position in compound 1, has been...... developed in our group. A similar strategy has been used for synthesising mimics of D-carbohydrates. The α,β-unsaturated lactone 3 was cyclised to compound 4 which was further transformed into 5. The nitrogen functionality in compound 7 is introduced by an Overman rearrangement of 6 and the hydroxyl...... functionalities was introduced by either epoxidation or dihydroxylation of 7. Finally, reduction of the lactone ring led to the sugar mimics 8. The synthesis of several isomers of 8 will be presented. [1] a) Kleban, M. ; Hilgers, P. ; Greul, J.N. ; Kugler, R.D. ; Li, J. ; Picasso, S. ; Vogel, P. ; Jäger, V. Chem...

Impeded Carbohydrate Metabolism in Rice Plants under Submergence Stress

Directory of Open Access Journals (Sweden)

Malay Kumar ADAK

2011-06-01

Full Text Available The detrimental effects of submergence on physiological performances of some rice varieties with special references to carbohydrate metabolisms and their allied enzymes during post-flowering stages have been documented and clarified in the present investigation. It was found that photosynthetic rate and concomitant translocation of sugars into the panicles were both related to the yield. The detrimental effects of the complete submergence were recorded in generation of sucrose, starch, sucrose phosphate synthase and phosphorylase activity in the developing panicles of the plants as compared to those under normal or control (i.e. non-submerged condition. The accumulation of starch was significantly lower in plants under submergence and that was correlated with ADP-glucose pyrophosphorylase activity. Photosynthetic rate was most affected under submergence in varying days of post-flowering and was also related to the down regulation of Ribulose bisphosphate carboxylase activity. However, under normal or control condition, there recorded a steady maintenance of photosynthetic rate at the post-flowering stages and significantly higher values of Ribulose bisphosphate carboxylase activity. Still, photosynthetic rate of the plants under both control and submerged conditions had hardly any significant correlation with sugar accumulation and other enzymes of carbohydrate metabolism like invertase with grain yield. Finally, plants under submergence suffered significant loss of yield by poor grain filling which was related to impeded carbohydrate metabolism in the tissues. It is evident that loss of yield under submergence is attributed both by lower sink size or sink capacity (number of panicles, in this case as well as subdued carbohydrate metabolism in plants and its subsequent partitioning into the grains.

Radiation chemistry of carbohydrates, ch. 5

International Nuclear Information System (INIS)

Dauphin, J.F.; Saint-Lebe, L.R.

1977-01-01

The physical and chemical changes undergone by carbohydrates at irradiation are reviewed. The discussion includes the irradiation of pure sugars (low molecular weight sugars and derivatives in the solid state or in solution; polysaccharides) as well as the irradiation of simple mixtures containing a given sugar, emphasizing the irradiation of foodstuffs containing one or more sugars

STICS: surface-tethered iterative carbohydrate synthesis.

Science.gov (United States)

Pornsuriyasak, Papapida; Ranade, Sneha C; Li, Aixiao; Parlato, M Cristina; Sims, Charles R; Shulga, Olga V; Stine, Keith J; Demchenko, Alexei V

2009-04-14

A new surface-tethered iterative carbohydrate synthesis (STICS) technology is presented in which a surface functionalized 'stick' made of chemically stable high surface area porous gold allows one to perform cost efficient and simple synthesis of oligosaccharide chains; at the end of the synthesis, the oligosaccharide can be cleaved off and the stick reused for subsequent syntheses.

DETERMINATION OF CARBOHYDRATE AND β-CAROTENE ...

African Journals Online (AJOL)

DR. AMINU

A sample of each vegetable was washed and ground to a fine pulp using pestle and mortar. The operation was done under dim light to reduce the rate of carotene oxidation contained in them. One gramme (1g) and 10g of macerated sample were weighed using Metler PT balance for carbohydrate and β-carotene analysis ...

Effect of Carbohydrate and Caffeine Ingestion on Badminton Performance.

Science.gov (United States)

Clarke, Neil D; Duncan, Michael J

2016-01-01

To investigate the effect of ingesting carbohydrate and caffeine solutions on measures that are central to success in badminton. Twelve male badminton players performed a badminton serve-accuracy test, coincidence-anticipation timing (CAT), and a choice reaction-time sprint test 60 min before exercise. Participants then consumed 7 mL/kg body mass of either water (PLA), 6.4% carbohydrate solution (CHO), a solution containing a caffeine dose of 4 mg/kg, or 6.4% carbohydrate and 4 mg/kg caffeine (C+C). All solutions were flavored with orange-flavored concentrate. During the 33-min fatigue protocol, participants were provided with an additional 3 mL/kg body mass of solution, which was ingested before the end of the protocol. As soon as the 33-min fatigue protocol was completed, all measures were recorded again. Short-serve accuracy was improved after the ingestion of CHO and C+C compared with PLA (P = .001, η(p)(2) = .50). Long-serve accuracy was improved after the ingestion of C+C compared with PLA (P badminton match can maintain serve accuracy, anticipation timing, and sprinting actions around the court.

Carbohydrate Mimetic Peptides Augment Carbohydrate-Reactive Immune Responses in the Absence of Immune Pathology

International Nuclear Information System (INIS)

Hennings, Leah; Artaud, Cecile; Jousheghany, Fariba; Monzavi-Karbassi, Behjatolah; Pashov, Anastas; Kieber-Emmons, Thomas

2011-01-01

Among the most challenging of clinical targets for cancer immunotherapy are Tumor Associated Carbohydrate Antigens (TACAs). To augment immune responses to TACA we are developing carbohydrate mimetic peptides (CMPs) that are sufficiently potent to activate broad-spectrum anti-tumor reactivity. However, the activation of immune responses against terminal mono- and disaccharide constituents of TACA raises concerns regarding the balance between “tumor destruction” and “tissue damage”, as mono- and disaccharides are also expressed on normal tissue. To support the development of CMPs for clinical trial testing, we demonstrate in preclinical safety assessment studies in mice that vaccination with CMPs can enhance responses to TACAs without mediating tissue damage to normal cells expressing TACA. BALB/c mice were immunized with CMPs that mimic TACAs reactive with Griffonia simplicifolia lectin 1 (GS-I), and tissue reactivity of serum antibodies were compared with the tissue staining profile of GS-I. Tissues from CMP immunized mice were analyzed using hematoxylin and eosin stain, and Luxol-fast blue staining for myelination. Western blots of membranes from murine mammary 4T1 cells, syngeneic with BALB/c mice, were also compared using GS-I, immunized serum antibodies, and naive serum antibodies. CMP immunization enhanced glycan reactivities with no evidence of pathological autoimmunity in any immunized mice demonstrating that tissue damage is not an inevitable consequence of TACA reactive responses

Carbohydrate Mimetic Peptides Augment Carbohydrate-Reactive Immune Responses in the Absence of Immune Pathology

Energy Technology Data Exchange (ETDEWEB)

Hennings, Leah; Artaud, Cecile; Jousheghany, Fariba; Monzavi-Karbassi, Behjatolah; Pashov, Anastas; Kieber-Emmons, Thomas, E-mail: tke@uams.edu [Winthrop P. Rockefeller Cancer Institute and Department of Pathology, University of Arkansas for Medical Sciences, Little Rock, AR 72205 (United States)

2011-11-11

Among the most challenging of clinical targets for cancer immunotherapy are Tumor Associated Carbohydrate Antigens (TACAs). To augment immune responses to TACA we are developing carbohydrate mimetic peptides (CMPs) that are sufficiently potent to activate broad-spectrum anti-tumor reactivity. However, the activation of immune responses against terminal mono- and disaccharide constituents of TACA raises concerns regarding the balance between “tumor destruction” and “tissue damage”, as mono- and disaccharides are also expressed on normal tissue. To support the development of CMPs for clinical trial testing, we demonstrate in preclinical safety assessment studies in mice that vaccination with CMPs can enhance responses to TACAs without mediating tissue damage to normal cells expressing TACA. BALB/c mice were immunized with CMPs that mimic TACAs reactive with Griffonia simplicifolia lectin 1 (GS-I), and tissue reactivity of serum antibodies were compared with the tissue staining profile of GS-I. Tissues from CMP immunized mice were analyzed using hematoxylin and eosin stain, and Luxol-fast blue staining for myelination. Western blots of membranes from murine mammary 4T1 cells, syngeneic with BALB/c mice, were also compared using GS-I, immunized serum antibodies, and naive serum antibodies. CMP immunization enhanced glycan reactivities with no evidence of pathological autoimmunity in any immunized mice demonstrating that tissue damage is not an inevitable consequence of TACA reactive responses.

Algal carbohydrates affect polyketide synthesis of the lichen-forming fungus Cladonia rangiferina.

Science.gov (United States)

Elshobary, Mostafa E; Osman, Mohamed E; Abo-Shady, Atef M; Komatsu, Emy; Perreault, Hélène; Sorensen, John; Piercey-Normore, Michele D

2016-01-01

Lichen secondary metabolites (polyketides) are produced by the fungal partner, but the role of algal carbohydrates in polyketide biosynthesis is not clear. This study examined whether the type and concentration of algal carbohydrate explained differences in polyketide production and gene transcription by a lichen fungus (Cladonia rangiferina). The carbohydrates identified from a free-living cyanobacterium (Spirulina platensis; glucose), a lichen-forming alga (Diplosphaera chodatii; sorbitol) and the lichen alga that associates with C. rangiferina (Asterochloris sp.; ribitol) were used in each of 1%, 5% and 10% concentrations to enrich malt yeast extract media for culturing the mycobiont. Polyketides were determined by high performance liquid chromatography (HPLC), and polyketide synthase (PKS) gene transcription was measured by quantitative PCR of the ketosynthase domain of four PKS genes. The lower concentrations of carbohydrates induced the PKS gene expression where ribitol up-regulated CrPKS1 and CrPKS16 gene transcription and sorbitol up-regulated CrPKS3 and CrPKS7 gene transcription. The HPLC results revealed that lower concentrations of carbon sources increased polyketide production for three carbohydrates. One polyketide from the natural lichen thallus (fumarprotocetraric acid) also was produced by the fungal culture in ribitol supplemented media only. This study provides a better understanding of the role of the type and concentration of the carbon source in fungal polyketide biosynthesis in the lichen Cladonia rangiferina. © 2016 by The Mycological Society of America.

Structure and function of complex carbohydrates active in regulating plant-microbe interactions

Energy Technology Data Exchange (ETDEWEB)

Albersheim, P; Darvill, A G; McNeil, M

1981-01-01

A key regulatory role of complex carbohydrates in the interactions between plants and microbes has been established. The complex carbohydrates act as regulatory molecules or hormones in that the carbohydrates induce de novo protein synthesis in receptive cells. The first complex carbohydrate recognized to possess such regulatory properties is a polysaccharide (PS) present in the walls of fungi. Hormonal concentrations of this PS elicit plant cells to accumulate phytoalexins (antibiotics). More recently we have recognized that a PS in the walls of growing plant cells also elicits phytoalexin accumulation; microbes and viruses may cause the release of active fragments of this endogenous elicitor. Another PS in plant cell walls is the Proteinase Inhibitor Inducing Factor (PIIF). This hormone appears to protect plants by inducing synthesis in plants of proteins which specifically inhibit digestive enzymes of insects and bacteria. Glycoproteins secreted by incompatible races (races that do not infect the plant) of a fungal pathogen of soybeans protect seedlings from attack by compatible races. Glycoproteins from compatible races do not protect the seedlings. The acidic PS secreted by the nitrogen-fixing rhizobia appear to function in the infection of legumes by the rhizobia. W.D. Bauer and his co-workers have evidence that these PS are required for the development of root hairs capable of being infected by symbiont rhizobia. Current knowledge of the structures of these biologically active complex carbohydrates will be presented.

A role for carbohydrate recognition in mammalian sperm-egg binding

International Nuclear Information System (INIS)

Clark, Gary F.

2014-01-01

Highlights: • Mammalian sperm-egg binding as a carbohydrate dependent species recognition event. • The role of carbohydrate recognition in human, mouse and pig sperm-egg binding. • Historical perspective and future directions for research focused on gamete binding. - Abstract: Mammalian fertilization usually requires three sequential cell–cell interactions: (i) initial binding of sperm to the specialized extracellular matrix coating the egg known as the zona pellucida (ZP); (ii) binding of sperm to the ZP via the inner acrosomal membrane that is exposed following the induction of acrosomal exocytosis; and (iii) adhesion of acrosome-reacted sperm to the plasma membrane of the egg cell, enabling subsequent fusion of these gametes. The focus of this review is on the initial binding of intact sperm to the mammalian ZP. Evidence collected over the past fifty years has confirmed that this interaction relies primarily on the recognition of carbohydrate sequences presented on the ZP by lectin-like egg binding proteins located on the plasma membrane of sperm. There is also evidence that the same carbohydrate sequences that mediate binding also function as ligands for lectins on lymphocytes that can inactivate immune responses, likely protecting the egg and the developing embryo up to the stage of blastocyst hatching. The literature related to initial sperm-ZP binding in the three major mammalian models (human, mouse and pig) is discussed. Historical perspectives and future directions for research related to this aspect of gamete adhesion are also presented

A role for carbohydrate recognition in mammalian sperm-egg binding

Energy Technology Data Exchange (ETDEWEB)

Clark, Gary F., E-mail: clarkgf@health.missouri.edu

2014-08-01

Highlights: • Mammalian sperm-egg binding as a carbohydrate dependent species recognition event. • The role of carbohydrate recognition in human, mouse and pig sperm-egg binding. • Historical perspective and future directions for research focused on gamete binding. - Abstract: Mammalian fertilization usually requires three sequential cell–cell interactions: (i) initial binding of sperm to the specialized extracellular matrix coating the egg known as the zona pellucida (ZP); (ii) binding of sperm to the ZP via the inner acrosomal membrane that is exposed following the induction of acrosomal exocytosis; and (iii) adhesion of acrosome-reacted sperm to the plasma membrane of the egg cell, enabling subsequent fusion of these gametes. The focus of this review is on the initial binding of intact sperm to the mammalian ZP. Evidence collected over the past fifty years has confirmed that this interaction relies primarily on the recognition of carbohydrate sequences presented on the ZP by lectin-like egg binding proteins located on the plasma membrane of sperm. There is also evidence that the same carbohydrate sequences that mediate binding also function as ligands for lectins on lymphocytes that can inactivate immune responses, likely protecting the egg and the developing embryo up to the stage of blastocyst hatching. The literature related to initial sperm-ZP binding in the three major mammalian models (human, mouse and pig) is discussed. Historical perspectives and future directions for research related to this aspect of gamete adhesion are also presented.

STEREOCHEMICAL ASPECTS OF HYDRATION OF CARBOHYDRATES IN AQUEOUS-SOLUTIONS .2. KINETIC MEDIUM EFFECTS

NARCIS (Netherlands)

GALEMA, SA; BLANDAMER, MJ; ENGBERTS, JBFN

1992-01-01

Rate constants for the hydrolysis of 1-benzoyl-3-phenyl-1,2,4-triazole in aqueous solutions of carbohydrates have been measured as a function of molality and nature of added mono- and disaccharides. The kinetic medium effects induced by the carbohydrates originate from hydration sphere overlap

Effect of training in the fasted state on metabolic responses during exercise with carbohydrate intake

DEFF Research Database (Denmark)

De Bock, K; Derave, W; Eijnde, B O

2008-01-01

program (6 wk, 3 day/wk, 1-2 h, 75% of peak Vo(2)) in moderately active males. They trained in the fasted (F; n = 10) or carbohydrate-fed state (CHO; n = 10) while receiving a standardized diet [65 percent of total energy intake (En) from carbohydrates, 20%En fat, 15%En protein]. Before and after...... the training period, substrate use during a 2-h exercise bout was determined. During these experimental sessions, all subjects were in a fed condition and received extra carbohydrates (1 g.kg body wt(-1) .h(-1)). Peak Vo(2) (+7%), succinate dehydrogenase activity, GLUT4, and hexokinase II content were...... adaptations in peak Vo(2) whether carried out in the fasted or carbohydrate-fed state. Although there was a decrease in exercise-induced glycogen breakdown and an increase in proteins involved in fat handling after fasting training, fat oxidation during exercise with carbohydrate intake was not changed....

[Evaluation of an original tool for carbohydrate counting, aimed at facilitating the implementation of functional insulin therapy].

Science.gov (United States)

Reach, Gérard; Choleau, Carine

2013-01-01

Carbohydrate counting is the most difficult component of functional insulin therapy. We thus designed a tool to facilitate carbohydrate counting of meals. The tool consists of an illustrated directory (16 x 10 cm, 119 pages) presenting 389 pictures of food, classified in 12 categories (breads, fruits, vegetables, etc.). For each photo, the name and mode of preparation of the foods are given, with the weight of the illustrated portion and its carbohydrate content as a multiple of 5 g. During the first phase of the study (3 days a week for 12 weeks), twelve patients with type 1 diabetes completed a precise food diary using a list and weight of all consumed foods. We were thus able to determine, for each of three meals (breakfast, lunch and dinner), the variability of their carbohydrate content. During the second phase of the study (2 weeks), the patients were given the possibility of using the illustrated food directory. We asked them first to estimate, from the photos, the global carbohydrate content of their meals, and then to weigh each food. This allowed us to calculate the true carbohydrate content of the meals from nutritional tables. During the first phase, the carbohydrate contents of breakfast, lunch and dinner were 67 +/- 29, 72 +/- 30 and 74 +/- 30 g, respectively (mean +/- SD, n = 12). For a given patient, the variability in the carbohydrate content of each meal was expressed by its standard deviation (SD). For the 12 patients, this variability was 18+/-+ 8, 25+/-+ 8 and 27+/-+ 11 g, respectively, for breakfast, lunch and dinner, and represented on the average about one-quarter of the total carbohydrate content. During the second phase, carbohydrate content, estimated by the patients using the illustrated food directory, correlated well with the retrospective evaluation based on nutritional tables (y = 0.95 x + 5 g, r2 = 0.8 ; n = 12, 235 meals). This new illustrated food repertory allows accurate evaluation of the highly variable carbohydrate content of

Determination of carbohydrates in fermentation processes by high-performance liquid chromatography

Energy Technology Data Exchange (ETDEWEB)

Plaga, A.; Stuempfel, J.; Fiedler, H.P. (Tuebingen Univ. (Germany, F.R.). Fakultaet fuer Biologie)

1989-11-01

HPLC is a universal, fast, accurate and selective method for the quantification of carbohydrates during fermentation processes. HPLC is not affected by complex constituents of fermentation media, such as meat extract, soybean meal or distillers solubles. The detection limit of the different investigated carbohydrates by refractive index monitoring ranges between 20 and 40 mg/l using a cation-exchange resin and between 50 and 100 mg/l using amino- or diol-bonded phases. (orig.).

Accumulation pattern of total nonstructural carbohydrate in ...

African Journals Online (AJOL)

The pattern of total nonstructural carbohydrate (TNC) accumulation in strawberry (Fragaria ananassa Duch.) nursery runner plants, cv. eCamarosaf, was determined for three growing seasons. Plant growth and fruit production patterns were also evaluated. The experiments were carried out on plants propagated in high ...

Simple mucin-type carbohydrates in normal and malignant human endometrium

DEFF Research Database (Denmark)

Ravn, V; Mandel, U; Svenstrup, B

1995-01-01

The simple mucin-type carbohydrate antigens, Tn, sialosyl-Tn, and T, are tumor-associated antigens of adenocarcinomas. We evaluated by immunohistochemistry the expression of Tn, sialosyl-Tn (s-Tn), T, and sialosyl-T (s-T) antigens in normal nonsecretory, early gestational, and malignant human...... and malignant endometrium, and the expression of s-T antigen was positively correlated with E2 levels in serum. Our findings suggest a hormonal influence on expression of simple mucin-type carbohydrates in human endometrium. However, the accumulation of Tn and s-Tn antigens in malignant endometrial cells seem...

Does caffeine alter muscle carbohydrate and fat metabolism during exercise?

DEFF Research Database (Denmark)

Graham, Terry E; Battram, Danielle S; Dela, Flemming

2008-01-01

and carbohydrate metabolism. While caffeine certainly mobilizes fatty acids from adipose tissue, rarely have measures of the respiratory exchange ratio indicated an increase in fat oxidation. However, this is a difficult measure to perform accurately during exercise, and small changes could be physiologically...... important. The few studies examining human muscle metabolism directly have also supported the fact that there is no change in fat or carbohydrate metabolism, but these usually have had a small sample size. We combined the data from muscle biopsy analyses of several similar studies to generate a sample size...

Studies on carbohydrate metabolism in Bacillus sphaericus 1593

African Journals Online (AJOL)

AJB SERVER

2006-10-02

Oct 2, 2006 ... Key words: Bacillus sphaericus, carbohydrate metabolism, glycolytic enzymes. ... available in soil close to decaying plant materials. So when a medium .... citrate, isocitrate, 2-oxoglutarate, malate and acetate. The unit of.

Effects of carbohydrate and caffeine ingestion on performance during a rugby union simulation protocol

OpenAIRE

Roberts, Simon P; Stokes, Keith A; Trewartha, Grant; Doyle, J; Hogben, P; Thompson, Dylan

2010-01-01

In this study, we investigated the effect of ingesting carbohydrate alone or with caffeine on performance of a rugby union-specific shuttle running protocol. On three occasions, at least one week apart in a counterbalanced trial order, eight male rugby union forwards ingested either placebo or carbohydrate (1.2g center dot kg-1 body mass center dot h-1) before and during a rugby union-specific protocol, with pre-exercise caffeine ingestion (4mg center dot kg-1) before one of the carbohydrate ...

Glycemic and lipid control in hospitalized type 2 diabetic patients: evaluation of 2 enteral nutrition formulas (low carbohydrate-high monounsaturated fat vs high carbohydrate).

Science.gov (United States)

León-Sanz, Miguel; García-Luna, Pedro P; Sanz-París, Alejandro; Gómez-Candela, Carmen; Casimiro, César; Chamorro, José; Pereira-Cunill, José L; Martin-Palmero, Angeles; Trallero, Roser; Martínez, José; Ordóñez, Francisco Javier; García-Peris, Pilar; Camarero, Emma; Gómez-Enterría, Pilar; Cabrerizo, Lucio; Perez-de-la-Cruz, Antonio; Sánchez, Carmen; García-de-Lorenzo, Abelardo; Rodríguez, Nelly; Usán, Luis

2005-01-01

Type 2 diabetic patients may need enteral nutrition support as part of their treatment. The objective was to compare glycemic and lipid control in hospitalized patients with type 2 diabetes requiring feeding via nasogastric tube using enteral feedings with either a highcarbohydrate or a high-monounsaturated-fat content. This trial included type 2 diabetes patients admitted to the hospital for neurologic disorders or head and neck cancer surgery who received either a low-carbohydrate-high-mono-unsaturated-fat (Glucerna) or a high-carbohydrate diet (Precitene Diabet). Glycemic and lipid control was determined weekly. Safety and gastrointestinal tolerance were also assessed. A total of 104 patients were randomized and 63 were evaluable according to preestablished protocol criteria. Median duration of therapy was 13 days in both groups. Mean glucose was significantly increased at 7 days of treatment (p = .006) in the Precitene arm, with no significant variations in the Glucerna arm. Mean weekly blood triglycerides levels in the Precitene arm were increased without reaching statistical significance, whereas patients in the Glucerna arm showed a stable trend. Patients in the Precitene arm showed a significantly higher incidence of diarrhea than patients in Glucerna arm (p = .008), whereas the incidence of nausea was smaller in the Precitene arm than in the Glucerna arm (p = .03). An enteral formula with lower carbohydrate and higher monounsaturated fat (Glucerna) has a neutral effect on glycemic control and lipid metabolism in type 2 diabetic patients compared with a high-carbohydrate and a lower-fat formula (Precitene Diabet).

A low-carbohydrate/high-fat diet reduces blood pressure in spontaneously hypertensive rats without deleterious changes in insulin resistance

OpenAIRE

Bosse, John D.; Lin, Han Yi; Sloan, Crystal; Zhang, Quan-Jiang; Abel, E. Dale; Pereira, Troy J.; Dolinsky, Vernon W.; Symons, J. David; Jalili, Thunder

2013-01-01

Previous studies reported that diets high in simple carbohydrates could increase blood pressure in rodents. We hypothesized that the converse, a low-carbohydrate/high-fat diet, might reduce blood pressure. Six-week-old spontaneously hypertensive rats (SHR; n = 54) and Wistar-Kyoto rats (WKY; n = 53, normotensive control) were fed either a control diet (C; 10% fat, 70% carbohydrate, 20% protein) or a low-carbohydrate/high-fat diet (HF; 20% carbohydrate, 60% fat, 20% protein). After 10 wk, SHR-...

Changes in atherogenic dyslipidemia induced by carbohydrate restriction in men are dependent on dietary protein source.

Science.gov (United States)

Mangravite, Lara M; Chiu, Sally; Wojnoonski, Kathleen; Rawlings, Robin S; Bergeron, Nathalie; Krauss, Ronald M

2011-12-01

Previous studies have shown that multiple features of atherogenic dyslipidemia are improved by replacement of dietary carbohydrate with mixed sources of protein and that these lipid and lipoprotein changes are independent of dietary saturated fat content. Because epidemiological evidence suggests that red meat intake may adversely affect cardiovascular disease risk, we tested the effects of replacing dietary carbohydrate with beef protein in the context of high- vs. low-saturated fat intake in 40 healthy men. After a 3-wk baseline diet [50% daily energy (E) as carbohydrate, 13% E as protein, 15% E as saturated fat], participants consumed for 3 wk each in a randomized crossover design two high-beef diets in which protein replaced carbohydrate (31% E as carbohydrate, 31% E as protein, with 10% E as beef protein). The high-beef diets differed in saturated fat content (8% E vs. 15% E with exchange of saturated for monounsaturated fat). Two-week washout periods were included following the baseline diet period and between the randomized diets periods. Plasma TG concentrations were reduced after the 2 lower carbohydrate dietary periods relative to after the baseline diet period and these reductions were independent of saturated fat intake. Plasma total, LDL, and non-HDL cholesterol as well as apoB concentrations were lower after the low-carbohydrate, low-saturated fat diet period than after the low-carbohydrate, high-saturated fat diet period. Given our previous observations with mixed protein diets, the present findings raise the possibility that dietary protein source may modify the effects of saturated fat on atherogenic lipoproteins.

The Effects of Breakfast Consumption and Composition on Metabolic Wellness with a Focus on Carbohydrate Metabolism.

Science.gov (United States)

Maki, Kevin C; Phillips-Eakley, Alyssa K; Smith, Kristen N

2016-05-01

Findings from epidemiologic studies indicate that there are associations between breakfast consumption and a lower risk of type 2 diabetes mellitus (T2DM) and metabolic syndrome, prompting interest in the influence of breakfast on carbohydrate metabolism and indicators of T2DM risk. The objective of this review was to summarize the available evidence from randomized controlled trials assessing the impact of breakfast on variables related to carbohydrate metabolism and metabolic wellness. Consuming compared with skipping breakfast appeared to improve glucose and insulin responses throughout the day. Breakfast composition may also be important. Dietary patterns high in rapidly available carbohydrate were associated with elevated T2DM risk. Therefore, partial replacement of rapidly available carbohydrate with other dietary components, such as whole grains and cereal fibers, proteins, and unsaturated fatty acids (UFAs), at breakfast may be a useful strategy for producing favorable metabolic outcomes. Consumption of fermentable and viscous dietary fibers at breakfast lowers glycemia and insulinemia. Fermentable fibers likely act through enhancing insulin sensitivity later in the day, and viscous fibers have an acute effect to slow the rate of carbohydrate absorption. Partially substituting protein for rapidly available carbohydrate enhances satiety and diet-induced thermogenesis, and also favorably affects lipoprotein lipids and blood pressure. Partially substituting UFA for carbohydrate has been associated with improved insulin sensitivity, lipoprotein lipids, and blood pressure. Overall, the available evidence suggests that consuming breakfast foods high in whole grains and cereal fiber, while limiting rapidly available carbohydrate, is a promising strategy for metabolic health promotion. © 2016 American Society for Nutrition.

Seasonal patterns of reserve and soluble carbohydrates in mature sugar maple (Acer saccharum)

Science.gov (United States)

B.L. Wong; K.L. Baggett; A.H. Rye

2003-01-01

Sugar maple (Acer saccharum Marsh.) trees exhibit seasonal patterns of production, accumulation, and utilization of nonstructural carbohydrates that are closely correlated with phenological events and (or) physiological processes. The simultaneous seasonal patterns of both reserve and soluble carbohydrates in the leaves, twigs, branches, and trunks of healthy mature...

Supramolecular Complexation of Carbohydrates for the Bioavailability Enhancement of Poorly Soluble Drugs.

Science.gov (United States)

Cho, Eunae; Jung, Seunho

2015-10-27

In this review, a comprehensive overview of advances in the supramolecular complexes of carbohydrates and poorly soluble drugs is presented. Through the complexation process, poorly soluble drugs could be efficiently delivered to their desired destinations. Carbohydrates, the most abundant biomolecules, have diverse physicochemical properties owing to their inherent three-dimensional structures, hydrogen bonding, and molecular recognition abilities. In this regard, oligosaccharides and their derivatives have been utilized for the bioavailability enhancement of hydrophobic drugs via increasing the solubility or stability. By extension, polysaccharides and their derivatives can form self-assembled architectures with poorly soluble drugs and have shown increased bioavailability in terms of the sustained or controlled drug release. These supramolecular systems using carbohydrate will be developed consistently in the field of pharmaceutical and medical application.

Ultraviolet-B effects on transcript levels for photosynthetic genes are not mediated through carbohydrate metabolism

International Nuclear Information System (INIS)

Mackerness, S.A.H.; Surplus, S.L.; Jordan, B.R.; Thomas, B.

1997-01-01

The relationship between UV-B-induced changes in gene expression and carbohydrate levels in pea seedlings has been investigated. The effect of supplementary UV-B radiation on the transcript abundance for two photosynthetic genes, photosynthesis, respiration and the levels of carbohydrates was determined in fully expanded leaves of 17-d-old pea seedlings under high (HL: 350 μmol m −2 s −1 ) and low (LL: 150 μmol m −2 s 1 ) light. Supplementary UV-B caused down regulation of the photosynthetic genes in green leaves under LL and to a lesser extent under HL. In contrast to previous studies, UV-B radiation resulted in a decrease in glucose levels rather than an increase under LL. Sucrose and starch levels were not affected until longer exposure. Effects of UV-B on carbohydrate levels were, however, minimal under HL. The effects on transcript levels were most marked under LL and therefore could not be attributed to elevated carbohydrate levels. Comparison of UV-B effects on carbohydrates in source (leaf) and sink (green buds) organs indicated that changes in carbohydrates in response to UV-B are probably indirect and arise from effects of UV-B on photosynthesis in source organs. (author)

Development and Testing the Technology of Complex Transformation of Carbohydrates from Vegetable Raw Materials into Bioethanol

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S.P. Tsygankov

2013-07-01

Full Text Available Results of development and testing the tentative technology of sweet sorghum and finger millet processing into bioethanol are described. The carbohydrates content and range of the studied vegetable biomass as the raw material is defined. Bioethanol potential output from sugar sorghum and finger millet carbohydrates and key technological parameters of preparation of both types of vegetable raw material for alcohol fermentation are defined. The concept of the tentative technology of bioethanol production from carbohydrate raw material of the first and second generations is offered. Testing of complex transformation of carbohydrates from vegetable raw materials into bioethanol is performed.

Circulating FGF21 in humans is potently induced by short term overfeeding of carbohydrates.

Science.gov (United States)

Lundsgaard, Anne-Marie; Fritzen, Andreas M; Sjøberg, Kim A; Myrmel, Lene S; Madsen, Lise; Wojtaszewski, Jørgen F P; Richter, Erik A; Kiens, Bente

2017-01-01

Fibroblast-growth factor 21 (FGF21) is thought to be important in metabolic regulation. Recently, low protein diets have been shown to increase circulating FGF21 levels. However, when energy contribution from dietary protein is lowered, other macronutrients, such as carbohydrates, must be increased to meet eucaloric balance. This raises the possibility that intake of a diet rich in carbohydrates may induce an increase in plasma FGF21 levels per se. Here we studied the role of dietary carbohydrates on the levels of circulating FGF21 and concomitant physiologic effects by feeding healthy men a carbohydrate rich diet without reducing protein intake. A diet enriched in carbohydrates (80 E% carbohydrate; CHO) and a eucaloric control diet (CON) were provided to nine healthy men for three days. The energy intake during the CHO diet was increased (+75% energy) to ensure similar dietary protein intake in CHO and CON. To control for the effect of caloric surplus, we similarly overfed (+75% energy) the same subjects for three days with a fat-rich diet (78 E% fat; FAT), consisting of primarily unsaturated fatty acids. The three diets were provided in random order. After CHO, plasma FGF21 concentration increased 8-fold compared to CON (329 ± 99 vs. 39 ± 9 pg ml -1 , p FAT only a non-significant tendency (p = 0.073) to an increase in plasma FGF21 concentration was found. The increase in FGF21 concentration after CHO correlated closely (r = 0.88, p carbohydrate, but not fat, led to markedly increased FGF21 secretion in humans, notably without protein restriction, and affected glucose and lipid homeostais.

Does prior acute exercise affect postexercise substrate oxidation in response to a high carbohydrate meal?

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Hickey Matthew S

2008-01-01

Full Text Available Abstract Background Consumption of a mixed meal increases postprandial carbohydrate utilization and decreases fat oxidation. On the other hand, acute endurance exercise increases fat oxidation and decreases carbohydrate utilization during the post-exercise recovery period. It is possible that the resulting post-exercise increase in circulating nonesterified fatty acids could attenuate the ability of ingested carbohydrate to inhibit lipid oxidation. The purpose of this study was to determine whether prior exercise attenuates the usual meal-induced decline in lipid oxidation. Methods Six healthy, physically active young subjects (x age = 26.3 years, 4 males, 2 females completed three treatments in random order after a ~10 h fast: (a Exercise/Carbohydrate (Ex/CHO – subjects completed a bout of exercise at 70% VO2peak (targeted net energy cost of 400 kcals, followed by consumption of a carbohydrate-rich meal; (b Exercise/Placebo (Ex/Placebo – subjects completed an identical bout of exercise followed by consumption of a placebo; and (c No Exercise/Carbohydrate (NoEx/CHO – subjects sat quietly rather than exercising and then consumed the carbohydrate-rich meal. Blood samples were obtained before and during the postprandial period to determine plasma glucose, insulin, and non-esterified fatty acids (NEFA. Respiratory gas exchange measures were used to estimate rates of fat and carbohydrate oxidation. Results Plasma NEFA were approximately two-fold higher immediately following the two exercise conditions compared to the no-exercise condition, while meal consumption significantly increased insulin and glucose in both Ex/CHO and NoEx/CHO. NEFA concentrations fell rapidly during the 2-h postprandial period, but remained higher compared to the NoEx/CHO treatment. Carbohydrate oxidation increased rapidly and fat oxidation decreased in response to the meal, with no differences in the rates of carbohydrate and fat oxidation during recovery between the Ex

Myostatin and carbohydrate disturbances.

Science.gov (United States)

Assyov, Yavor S; Velikova, Tsvetelina V; Kamenov, Zdravko A

2017-05-01

Purpose/aim of the study: Myostatin is a myokine that has been shown to inhibit muscle growth and to have potentially deleterious effects on metabolism. The aim of the current study was to compare its circulating serum levels in subjects from the whole spectrum of carbohydrate disturbances leading to diabetes. A total of 159 age-, sex-, and BMI-matched subjects participated in the study - 50 had normal glucose tolerance (NGT), 60 had prediabetes (PreDM), and 49 had type 2 diabetes mellitus (T2D). Oral glucose tolerance testing was used to determine glucose tolerance. Serum myostatin was quantified by means of ELISA. Circulating serum myostatin levels were highest in patients with T2D, lower in subjects with prediabetes, and lowest in subjects with normoglycemia (all p Myostatin was shown to be positively associated with fasting plasma glucose, HOMA-IR, hepatic enzymes, uric acid, and FINDRISC questionnaire scores in both sexes. ROC analyses determined circulating myostatin levels to be of value for differentiating subjects with T2D (AUC = 0.72, p = 0.002 in men; AUC = 0.70, p = 0.004 in women) in the study population. After adjustment for potential confounders, in a multiple binary logistic regression model, serum myostatin added further information to traditional risk estimates in distinguishing subjects with T2D. Serum myostatin levels are higher with deterioration of carbohydrate tolerance. Furthermore, circulating myostatin is positively associated with traditional biochemical estimates of poor metabolic health. These data add to evidence of the involvement of this myokine in the pathogenesis of T2D.

Inhibition of mannosidase in hybridomas yields monoclonal antibodies with greater capacity for carbohydrate labeling

International Nuclear Information System (INIS)

Simonson, R.B.; Ultee, M.E.; Long, C.G.; Gillette, R.W.; McKearn, T.J.; Rodwell, J.D.

1988-01-01

Labeling an antibody site specifically through its carbohydrate residues preserves more of its antigen-binding activity than does labeling through protein moieties. To boost the amount of immunoglobulin G carbohydrate capable of being labeled, we treated hybridoma cells with a mannosidase inhibitor, deoxymannojirimycin (dMM). Polyacrylamide gel electrophoresis showed formation of a glycoprotein with high mannose content, in that endo-beta-N-acetylglucosaminidase H 3.2.1.96) could digest the antibody from the dMM-treated cells, but not from control cultures. Carbohydrate analysis confirmed this conclusion, indicating that the antibody from the dMM-treated cells had twice as much mannose as did the control antibody. The glucosamine content of the treated-cells' antibodies was half that of the control, and no additional carbohydrate residues were detectable in the antibodies secreted by the dMM-treated cells. We conjugated both the dMM and control antibodies through their carbohydrate to a chelator. In labeling, the dMM antibody conjugate incorporated approximately threefold as much 111 In isotope as the control conjugate. The two labeled antibodies were injected into mice and showed similar organ distributions

Profiling of carbohydrate polymers in biotechnology using ...

African Journals Online (AJOL)

The analysis of carbohydrate polymers is very demanding and challenging because of the similar physical and chemical properties they possess. Enzymatic hydrolysis is employed to cleave the polymers. The use of enzymes in analytical chemistry requires an analytical system that has on-line capability, is fast, ...

Accumulation pattern of total nonstructural carbohydrate in ...

African Journals Online (AJOL)

Umukoro

1977-09-09

Sep 9, 1977 ... 1Instituto Nacional de Tecnología Agropecuaria (INTA), EEA Famaillá, Argentina. 2Department of Plant Sciences, University of California Davis, CA, USA. Accepted 17 October, 2012. The pattern of total nonstructural carbohydrate (TNC) accumulation in strawberry (Fragaria ananassa. Duch.) nursery ...

Particulate carbohydrates in the Bay of Bengal

Digital Repository Service at National Institute of Oceanography (India)

Bhosle, N.B.; Nandakumar, K.; Venkat, K.

Particulate matter collected from 77 water samples over a 3000 m water column was analyzed for particulate carbohydrates (PCHO). PCHO in the surface waters ranged from 43 to 143 mu g.l-1, and below 250 m it was 16.PCHO showed large variations at all...

A low-carbohydrate/high-fat diet improves glucoregulation in type 2 diabetes mellitus by reducing postabsorptive glycogenolysis

NARCIS (Netherlands)

Allick, G; Bisschop, PH; Ackermans, MT; Endert, E; Meijer, AJ; Kuipers, F; Sauerwein, HP; Romijn, JA

2004-01-01

The aim of this study was to examine the mechanisms by which dietary carbohydrate and fat modulate fasting glycemia. We compared the effects of an eucaloric high-carbohydrate (89% carbohydrate) and high-fat (89% fat) diet on fasting glucose metabolism and insulin sensitivity in seven obese patients

The human small intestinal microbiota is driven by rapid uptake and conversion of simple carbohydrates

DEFF Research Database (Denmark)

Zoetendal, Erwin G; Raes, Jeroen; van den Bogert, Bartholomeus

2012-01-01

in parallel. Comparative functional analysis with fecal metagenomes identified functions that are overrepresented in the small intestine, including simple carbohydrate transport phosphotransferase systems (PTS), central metabolism and biotin production. Moreover, metatranscriptome analysis supported high...... level in-situ expression of PTS and carbohydrate metabolic genes, especially those belonging to Streptococcus sp. Overall, our findings suggest that rapid uptake and fermentation of available carbohydrates contribute to maintaining the microbiota in the human small intestine....

Disorders of carbohydrate metabolism in clinical practice

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V.I. Pankiv

2017-02-01

Full Text Available Considering the prevalence of diabetes mellitus (DM, the possibility of early and rapid progress of complications, a large number of undiagnosed cases and disappointing forecasts of the World Health Organization on the prospects of DM spreading in the world, timely and accurate diagnosis of carbohydrate metabolism disorders is important. The criteria for the diagnosis of carbohydrate metabolism and DM are shown in the article. The article includes a new consensus on the staging of type 1 DM and a discussion of a proposed unifying diabetes classification scheme that focuses on β-cell dysfunction and disease stage as indicated by glucose status. Modern recommendations 2017 of the American Diabetes Association are shown in relation to the criteria of diagnostics of impaired fasting glucose, impaired glucose tolerance and diabetes mellitus. The value of insulin resistance and functional state of pancreatic β-cells is underlined in determination of type 2 DM duration. A plan of type 2 DM management is brought.

Role of carbohydrate metabolism in grass tetany

Energy Technology Data Exchange (ETDEWEB)

Miller, J.K.; Madsen, F.C.; Lentz, D.E.; Hansard, S.L.

1977-01-01

Clinical hypomagnesemia is confined primarily to beef cattle in the United States but also occurs in dairy cattle in other countries, probably due to different management practices. During periods when grass tetany is likely, early vegetative temperate zone grasses are usually low in total readily available carbohydrates and magnesium but high in potassium and nitrogen. The tetany syndrome may include hypoglycemia and ketosis, suggesting an imbalance in intermediary energy metabolism. Many enzyme systems critical to cellular metabolism, including those which hydrolyze and transfer phosphate groups, are activated by Mg. Thus, by inference, Mg is required for normal glucose utilization, fat, protein, nucleic acid and coenzyme synthesis, muscle contraction, methyl group transfer, and sulfate, acetate, and formate activation. Numerous clinical and experimental studies suggest an intimate relationship between metabolism of Mg and that of carbohydrate, glucagon, and insulin. The objective is to review this literature and suggest ways in which these relationships might contribute to a chain of events leading to grass tetany.

The bacterial metabolism of carbohydrates used in tests of intestinal permeability

OpenAIRE

Qureishy, Gulzar A.

1984-01-01

Carbohydrates have been used for tests of intestinal function for many years and the impaired absorption of carbohydrates in the intestinal lumen is either due to the damaged intestinal absorptive surface, as in coeliac disease etc., in some types of acute gastroenteritis , when the absorptive area is reduced by villous atrophy , or due to the bacterial overgrowth in the small intestinal lumen as in blind loop syndrome , some types of malabsorption , which possibly produce alteration in the m...

Dietary carbohydrate composition can change waste production and biofilter load in recirculating aquaculture systems

NARCIS (Netherlands)

Meriac, A.; Eding, E.H.; Schrama, J.W.; Kamstra, A.; Verreth, J.A.J.

2014-01-01

This study investigated the effect of dietary carbohydrate composition on the production, recovery and degradability of fecal waste from rainbow trout (Oncorhynchus mykiss) in recirculating aquaculture systems (RAS). Dietary carbohydrate composition was altered by substituting starch with non-starch

Effects of oral contraceptive agents and sex steroids on carbohydrate metabolism.

Science.gov (United States)

Kalkhoff, R K

1972-01-01

The article offers a general interpretation of the influence of oral contraceptive agents on glucose tolerance, emphasizing comparisons of synthetic sex hormones. Although there are conflicting reports on steroid-induced diabetes in normal women, their glucose curves are often higher when under oral contraceptive treatment, suggesting that oral contraceptives may induce a form of subclinical diabetes melitus that is reversible. Evidence from diabetic women suggests definite deliterious effects from contraceptive administration. Estradiol, estriol, and estrone may improve glucose tolerance in nondiabetic women and reduce insulin requirements in diabetics. Progesterone has little effect on carbohydrate tolerance, as did synthetic progestin. Conjugated equine estrogens (equilenine or Premarin) may provoke mild to moderate deterioration of carbohydrate tolerance. Parenterally administered natural estrogens and orally administered synthetic derivatives appear to differ sharply in their effects. Sex hormones' effects on carbohydrate metabolism likely involve interactions with insulin and endogenous glucocorticoids.

Weight loss with a low-carbohydrate, Mediterranean, or low-fat diet.

Science.gov (United States)

Shai, Iris; Schwarzfuchs, Dan; Henkin, Yaakov; Shahar, Danit R; Witkow, Shula; Greenberg, Ilana; Golan, Rachel; Fraser, Drora; Bolotin, Arkady; Vardi, Hilel; Tangi-Rozental, Osnat; Zuk-Ramot, Rachel; Sarusi, Benjamin; Brickner, Dov; Schwartz, Ziva; Sheiner, Einat; Marko, Rachel; Katorza, Esther; Thiery, Joachim; Fiedler, Georg Martin; Blüher, Matthias; Stumvoll, Michael; Stampfer, Meir J

2008-07-17

Trials comparing the effectiveness and safety of weight-loss diets are frequently limited by short follow-up times and high dropout rates. In this 2-year trial, we randomly assigned 322 moderately obese subjects (mean age, 52 years; mean body-mass index [the weight in kilograms divided by the square of the height in meters], 31; male sex, 86%) to one of three diets: low-fat, restricted-calorie; Mediterranean, restricted-calorie; or low-carbohydrate, non-restricted-calorie. The rate of adherence to a study diet was 95.4% at 1 year and 84.6% at 2 years. The Mediterranean-diet group consumed the largest amounts of dietary fiber and had the highest ratio of monounsaturated to saturated fat (Pcarbohydrate group consumed the smallest amount of carbohydrates and the largest amounts of fat, protein, and cholesterol and had the highest percentage of participants with detectable urinary ketones (Ploss was 2.9 kg for the low-fat group, 4.4 kg for the Mediterranean-diet group, and 4.7 kg for the low-carbohydrate group (Plosses were 3.3 kg, 4.6 kg, and 5.5 kg, respectively. The relative reduction in the ratio of total cholesterol to high-density lipoprotein cholesterol was 20% in the low-carbohydrate group and 12% in the low-fat group (P=0.01). Among the 36 subjects with diabetes, changes in fasting plasma glucose and insulin levels were more favorable among those assigned to the Mediterranean diet than among those assigned to the low-fat diet (Pcarbohydrate diets may be effective alternatives to low-fat diets. The more favorable effects on lipids (with the low-carbohydrate diet) and on glycemic control (with the Mediterranean diet) suggest that personal preferences and metabolic considerations might inform individualized tailoring of dietary interventions. (ClinicalTrials.gov number, NCT00160108.) 2008 Massachusetts Medical Society

Phakopsora euvitis Causes Unusual Damage to Leaves and Modifies Carbohydrate Metabolism in Grapevine

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Antonio F. Nogueira Júnior

2017-09-01

Full Text Available Asian grapevine rust (Phakopsora euvitis is a serious disease, which causes severe leaf necrosis and early plant defoliation. These symptoms are unusual for a strict biotrophic pathogen. This work was performed to quantify the effects of P. euvitis on photosynthesis, carbohydrates, and biomass accumulation of grapevine. The reduction in photosynthetic efficiency of the green leaf tissue surrounding the lesions was quantified using the virtual lesion concept (β parameter. Gas exchange and responses of CO2 assimilation to increasing intercellular CO2 concentration were analyzed. Histopathological analyses and quantification of starch were also performed on diseased leaves. Biomass and carbohydrate accumulation were quantified in different organs of diseased and healthy plants. Rust reduced the photosynthetic rate, and β was estimated at 5.78, indicating a large virtual lesion. Mesophyll conductance, maximum rubisco carboxylation rate, and regeneration of ribulose-1,5-bisphosphate dependent on electron transport rate were reduced, causing diffusive and biochemical limitations to photosynthesis. Hypertrophy, chloroplast degeneration of mesophyll cells, and starch accumulation in cells close to lesions were observed. Root carbohydrate concentration was reduced, even at low rust severity. Asian grapevine rust dramatically reduced photosynthesis and altered the dynamics of production and accumulation of carbohydrates, unlike strict biotrophic pathogens. The reduction in carbohydrate reserves in roots would support polyetic damage on grapevine, caused by a polycyclic disease.

Response of C57Bl/6 mice to a carbohydrate-free diet

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Borghjid Saihan

2012-07-01

Full Text Available Abstract High fat feeding in rodents generally leads to obesity and insulin resistance whereas in humans this is only seen if dietary carbohydrate is also high, the result of the anabolic effect of poor regulation of glucose and insulin. A previous study of C57Bl/6 mice (Kennedy AR, et al.: Am J Physiol Endocrinol Metab (2007 262 E1724-1739 appeared to show the kind of beneficial effects of calorie restriction that is seen in humans but that diet was unusually low in protein (5%. In the current study, we tested a zero-carbohydrate diet that had a higher protein content (20%. Mice on the zero-carbohydrate diet, despite similar caloric intake, consistently gained more weight than animals consuming standard chow, attaining a dramatic difference by week 16 (46.1 ± 1.38 g vs. 30.4 ± 1.00 g for the chow group. Consistent with the obese phenotype, experimental mice had fatty livers and hearts as well as large fat deposits in the abdomino-pelvic cavity, and showed impaired glucose clearance after intraperitoneal injection. In sum, the response of mice to a carbohydrate-free diet was greater weight gain and metabolic disruptions in distinction to the response in humans where low carbohydrate diets cause greater weight loss than isocaloric controls. The results suggest that rodent models of obesity may be most valuable in the understanding of how metabolic mechanisms can work in ways different from the effect in humans.

Carbohydrates, uronic acids and alkali extractable carbohydrates in contrasting marine and estuarine sediments: Distribution, size fractionation and partial chemical characterization

Digital Repository Service at National Institute of Oceanography (India)

Khodse, V.B.; Fernandes, L.; Bhosle, N.B.; Sardessai, S.

terrestrial plants, bacteria and phytoplankton, however, the influence of the former was relatively greater in sediments of the ME and BOB, as well as in residual sediments of ME. Approximately 11-21% of total carbohydrates could be extracted using hot alkali...

Clinical trial experience with fat-restricted vs. carbohydrate-restricted weight-loss diets.

Science.gov (United States)

Klein, Samuel

2004-11-01

It is unlikely that one diet is optimal for all overweight or obese persons. Both low-fat and low-carbohydrate diets have been shown to induce weight loss and reduce obesity-related comorbidities. Low-carbohydrate diets cause greater short-term (up to 6 months) weight loss than low-fat diets, but the long-term clinical safety and efficacy of these diets has not been studied.

Modifying the Dietary Carbohydrate-to-Protein Ratio Alters the Postprandial Macronutrient Oxidation Pattern in Liver of AMPK-Deficient Mice.

Science.gov (United States)

Chalvon-Demersay, Tristan; Even, Patrick C; Chaumontet, Catherine; Piedcoq, Julien; Viollet, Benoit; Gaudichon, Claire; Tomé, Daniel; Foretz, Marc; Azzout-Marniche, Dalila

2017-09-01

Background: Hepatic AMP-activated kinase (AMPK) activity is sensitive to the dietary carbohydrate-to-protein ratio. However, the role of AMPK in metabolic adaptations to variations in dietary macronutrients remains poorly understood. Objective: The objective of this study was to determine the role of hepatic AMPK in the adaptation of energy metabolism in response to modulation of the dietary carbohydrate-to-protein ratio. Methods: Male 7-wk-old wild-type (WT) and liver AMPK-deficient (knockout) mice were fed either a normal-protein and normal-carbohydrate diet (NP-NC; 14% protein, 76% carbohydrate on an energy basis), a low-protein and high-carbohydrate diet (LP-HC; 5% protein, 85% carbohydrate), or a high-protein and low-carbohydrate diet (HP-LC; 55% protein, 35% carbohydrate) for 3 wk. During this period, after an overnight fast, metabolic parameters were measured and indirect calorimetry was performed in mice during the first hours after refeeding a 1-g calibrated meal of their own diet in order to investigate lipid and carbohydrate metabolism. Results: Knockout mice fed an LP-HC or HP-LC meal exhibited 24% and 8% lower amplitudes in meal-induced carbohydrate and lipid oxidation changes. By contrast, knockout mice fed an NP-NC meal displayed normal carbohydrate and lipid oxidation profiles. These mice exhibited a transient increase in hepatic triglycerides and a decrease in hepatic glycogen. These changes were associated with a 650% higher secretion of fibroblast growth factor 21 (FGF21) 2 h after refeeding. Conclusions: The consequences of hepatic AMPK deletion depend on the dietary carbohydrate-to-protein ratio. In mice fed the NP-NC diet, deletion of AMPK in the liver led to an adaptation of liver metabolism resulting in increased secretion of FGF21. These changes possibly compensated for the absence of hepatic AMPK, as these mice exhibited normal postprandial changes in carbohydrate and lipid oxidation. By contrast, in mice fed the LP-HC and HP-LC diets, the

The influence of nutrient and water availability on carbohydrate storage in loblolly pine

Science.gov (United States)

K.H. Ludovici; H.L. Allen; T.J. Albaugh; P.M. Dougherty

2002-01-01

We quantified the effects of nutrient and water availability on monthly whole-tree carbohydrate budgets and determined allocation patterns of storage carbohydrates in loblolly pine (Pinus taeda) to test site resource impacts on internal carbon (C) storage. A factorial combination of two nutrient and two irrigation treatments were imposed on a 7-year...

Study for the identification of irradiated carbohydrate containing food

International Nuclear Information System (INIS)

Scherz, H.

1991-01-01

The study was undertaken to find radiation specific substances of carbohydrates and methods to detect those ones in irradiated food. Deoxycompounds have been found by irradiation of carbohydrates. It could be stated, that the formation of these substances was radiation specific. The irradiation of wheat for desinfestation was high actual at the moment of this study and therefore it was tried to find these deoxycompounds in irradiated potato starch and wheat flour. These substances were isolated and one of them was identified as w-hydroxymaltol. This substance was also found in irradiated wheat flour. The dependence between the amount of w-hydroxymaltol and the irradiation dosage was determined for both materials. (7 refs, 2 figs)

[Clinical-diagnostic estimation of carbohydrates metabolism in obturation jaundice].

Science.gov (United States)

Nychytaĭlo, M Iu; Malyk, S V

2004-07-01

Complex examination of 175 patients with obturation jaundice was conducted, peculiar attention was spared to the carbohydrates metabolism changes, characterizing hepatic state. It was established, that in obturation jaundice in the liver there are occurring inflammatory changes and disturbances of all kinds of metabolism, including that of carbohydrates, severity of which depends on duration of jaundice, the concurrent diseases presence, they shows lowering of the glucose and glycogen level in the blood, as well as the hepatic glycogen content, that's why they may be applied as a complex of prognostic criterions for the disease course. An early conduction of operative treatment, elimination of the biliary ducts impassability promote the rehabilitation period shortening and the hepatic functional activity normalization.

A low-carbohydrate survey: Evidence for sustainable metabolic syndrome reversal

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Mark T. Cucuzzella

2017-12-01

Full Text Available Background: Metabolic syndrome has become a significant problem, with the American Diabetes Association estimating the cost of diabetes and pre-diabetes in the United States alone to be $322 billion per year. Numerous clinical trials have demonstrated the efficacy of low-carbohydrate diets in reversing metabolic syndrome and its associated disorders. Aim: This study was designed to examine how voluntary adherents to a low-carbohydrate diet rate its effectiveness and sustainability using an online survey. Setting and methods: The 57-question survey was administered online and shared internationally via social media and ‘low-carb’ communities. Where appropriate, chi-squared tests and paired t-tests were used to analyse the responses. Results: There were 1580 respondents. The majority of respondents had consumed less than 100 g of carbohydrates per day for over a year, typically for reasons of weight loss or disease management. There was a reported decrease in waist circumference and weight with a simultaneous decrease in hunger and increase in energy level. Of those who provided laboratory values, the majority saw improvements in their HbA1c, blood glucose measurements, and lipid panel results. There was a reduction in usage of various medications, and 25% reported medication cost savings, with average monthly savings of $288 for those respondents. In particular, the usage of pain relievers and anti-inflammatories dropped with a simultaneous decreased rating of pain and increase in mobility. Conclusion: We conclude that low-carbohydrate diets are a sustainable method of metabolic syndrome reversal in a community setting.

Intestinal absorption of copper: influence of carbohydrates.

Science.gov (United States)

Wapnir, R A; Balkman, C

1992-02-01

Macronutrients can modulate the intestinal absorption of trace elements by binding the metal or altering mucosal function. We investigated whether certain simple and complex carbohydrates modify copper (Cu) absorption, using an in vivo perfusion technique in the rat. Corn syrup solids, which contain a mixture of glucose polymers of diverse length, added at either 20 or 50 mosm/kg enhanced Cu absorption from a 31.5 microM (2 mg/liter) Cu solution (128 +/- 11 and 130 +/- 11 pmol/min x cm, respectively, vs 101 +/- 4 pmol/min x cm, P less than 0.05, in the absence of carbohydrate). This was concomitant with a stimulation of net water absorption (1.05 +/- 0.08 and 0.84 +/- 0.08 microliter/min x cm, respectively, vs 0.63 +/- 0.02 microliter/min x cm with no carbohydrate, P less than 0.05). Glucose, fructose, lactose, or sucrose had no influence on Cu absorption, although they altered water exchanges, an effect attributable to a reduction of the outflow component of fluid recirculation. Low concentrations of lactose resulted in a greater accumulation of Cu in the intestinal mucosa (8.75 +/- 0.71 micrograms/g vs 5.77 +/- 0.68 micrograms/g for controls, P less than 0.05). Hence, solutes that moderately stimulate mucosa-to-serosa fluid influx in a progressive manner, such as glucose polymers, may contribute to functionally increase Cu absorption. Conversely, conditions which tend to reduce water inflow or increase water outflow across the small intestinal mucosa, as may occur with high lactose diets or in cases of chronic diarrhea, may have negative effects.

The Influence of Serial Carbohydrate Mouth Rinsing on Power Output during a Cycle Sprint.

Science.gov (United States)

Phillips, Shaun M; Findlay, Scott; Kavaliauskas, Mykolas; Grant, Marie Clare

2014-05-01

The objective of the study was to investigate the influence of serial administration of a carbohydrate (CHO) mouth rinse on performance, metabolic and perceptual responses during a cycle sprint. Twelve physically active males (mean (± SD) age: 23.1 (3.0) years, height: 1.83 (0.07) m, body mass (BM): 86.3 (13.5) kg) completed the following mouth rinse trials in a randomized, counterbalanced, double-blind fashion; 1. 8 x 5 second rinses with a 25 ml CHO (6% w/v maltodextrin) solution, 2. 8 x 5 second rinses with a 25 ml placebo (PLA) solution. Following mouth rinse administration, participants completed a 30 second sprint on a cycle ergometer against a 0.075 g·kg(-1) BM resistance. Eight participants achieved a greater peak power output (PPO) in the CHO trial, resulting in a significantly greater PPO compared with PLA (13.51 ± 2.19 vs. 13.20 ± 2.14 W·kg(-1), p 0.05). No significant between-trials difference was reported for fatigue index, perceived exertion, arousal and nausea levels, or blood lactate and glucose concentrations. Serial administration of a CHO mouth rinse may significantly improve PPO during a cycle sprint. This improvement appears confined to the first 5 seconds of the sprint, and may come at a greater relative cost for the remainder of the sprint. Key pointsThe paper demonstrates that repeated administration of a carbohydrate mouth rinse can significantly improve peak power output during a single 30 second cycle sprint.The ergogenic effect of the carbohydrate mouth rinse may relate to the duration of exposure of the oral cavity to the mouth rinse, and associated greater stimulation of oral carbohydrate receptors.The significant increase in peak power output with the carbohydrate mouth rinse may come at a relative cost for the remainder of the sprint, evidenced by non-significantly lower mean power output and a greater fatigue index in the carbohydrate vs. placebo trial.Serial administration of a carbohydrate mouth rinse may be beneficial for

Effects of irradiation and heating on extraction of carbohydrates from brown seaweed, gagome Kjellmaniella crassifolia

International Nuclear Information System (INIS)

Suzuki, T.; Yoshie, Y.; Shirai, T.; Hirano, T.

1993-01-01

Changes in dissolved carbohydrates from Gagome Kjemaniella crassifolia by gamma-irradiation and boiling were investigated. When pulverized Gagome was irradiated in the dry state, solubilized carbohydrate levels did not change at dose levels up to 50 kGy; however, the molecular weights of main components in the soluble matter decreased. The amount of dissolved carbohydrates increased with dosage increments of gamma rays when irradiated in water, and their molecular weights decreased markedly. When Gagome was irradiated with a dose of 10 kGy in the dry state, and then boiled in water, the amounts of carbohydrates dissolved were markedly high at 80 degree C during 10-h boiling in comparison with those of the non-irradiated control. On the other hand, at 100 degree C no difference was observed after 4-h boiling. There was no significant difference in the quantity of dissolved carbohydrates or their molecular weights between irradiated and non-irradiated samples heated at 120 degree C for up to 12 h. From these results dietary fibers in Gagome were found to be extracted and degradated by irradiation

The Role of Carbohydrate Related Factors in Pathogenesis of Nonalcoholic Fatty Liver Disease: A Review

Directory of Open Access Journals (Sweden)

Saeed Sherafatmanesh

2017-06-01

Full Text Available Nonalcoholic fatty liver disease (NAFLD is among the most common causes of chronic liver disease worldwide and its prevalence is increasing nowadays. This review article discusses the role of carbohydrate in NAFLD. We reviewed 57 papers out of which 48 randomized controlled trials and review articles with good quality were collected. The key words used for the search were: “Carbohydrate”, “Fructose”, “Weight”, “Low carbohydrate, ketogenic diet”, in combination with “NAFLD” for searching in “Pubmed”, ”Science direct” and “Google Scholar” databases. We limited our search to studies published in English. The available data provided adequate scientific evidence which pointed toward the considerable potential effects between high intake of carbohydrates, fructose, high glycemic index foods and low dietary fiber and incidence of the NAFLD. This review provided sufficient evidence that higher consumption of carbohydrates and fructose sources may exacerbate NAFLD which leads to more accumulation of fat in the liver; while higher intake of fiber and low GI carbohydrate tends to ameliorate NAFLD.

Gastric emptying, glucose metabolism and gut hormones: Evaluation of a common preoperative carbohydrate beverage

NARCIS (Netherlands)

Vermeulen, M.A.R.; Richir, M.C.; Garretsen, M.K.; van Schie, A.; Ghatei, M.A.; Holst, J.J.; Heijboer, A.C.; Uitdehaag, B.M.J.; Diamant, M.; Eekhoff, E.M.W.; van Leeuwen, P.A.M.; Ligthart-Melis, G.C.

2011-01-01

Objective: To study the gastric-emptying rate and gut hormonal response of two carbohydrate-rich beverages. A specifically designed carbohydrate-rich beverage is currently used to support the surgical patient metabolically. Fruit-based beverages may also promote recovery, due to natural antioxidant

Gastric emptying, glucose metabolism and gut hormones: evaluation of a common preoperative carbohydrate beverage

NARCIS (Netherlands)

Vermeulen, Mechteld A. R.; Richir, Milan C.; Garretsen, Martijn K.; van Schie, Annelies; Ghatei, Mohammed A.; Holst, Jens J.; Heijboer, Annemieke C.; Uitdehaag, Bernard M. J.; Diamant, Michaela; Eekhoff, E. Marelise W.; van Leeuwen, Paul A. M.; Ligthart-Melis, Gerdien C.

2011-01-01

To study the gastric-emptying rate and gut hormonal response of two carbohydrate-rich beverages. A specifically designed carbohydrate-rich beverage is currently used to support the surgical patient metabolically. Fruit-based beverages may also promote recovery, due to natural antioxidant and

Regioselective Benzoylation of Diols and Carbohydrates by Catalytic Amounts of Organobase.

Science.gov (United States)

Lu, Yuchao; Hou, Chenxi; Ren, Jingli; Xin, Xiaoting; Xu, Hengfu; Pei, Yuxin; Dong, Hai; Pei, Zhichao

2016-05-17

A novel metal-free organobase-catalyzed regioselective benzoylation of diols and carbohydrates has been developed. Treatment of diol and carbohydrate substrates with 1.1 equiv. of 1-benzoylimidazole and 0.2 equiv. of 1,8-diazabicyclo[5.4.0]undec-7-ene (DBU) in MeCN under mild conditions resulted in highly regioselective benzoylation for the primary hydroxyl group. Importantly, compared to most commonly used protecting bulky groups for primary hydroxyl groups, the benzoyl protective group offers a new protection strategy.

Effect of Low Carbohydrate Diet (LCD) for Diabetic Patients with Hypertriglycemia

OpenAIRE

Ebe, Koji; Bando, Hiroshi; Muneta, Tetsuo; Bando, Masahiro; Yonei, Yoshikazu

2017-01-01

Background: Arguments have continued for long concerning low carbohydrate diet and calorie restriction (calorie-restricted diet). Authors have reported clinical studies of low carbohydrate diet on ketone bodies, glucose variability and Morbus value so far. Subjects and methods: Subjects are 28 patients with Type 2 diabetes mellitus, which were 20/8 (M/F) with 48.3 ± 13.9 years old with serum triglyceride more than 250 mg/dL on blood sampling with overnight fasting. They were admitted for 14 d...

Morphological Specifications of the Bird Schistosome Cercariae and Surface Carbohydrates as Receptors for Lectins

Directory of Open Access Journals (Sweden)

I Moebedi

2007-04-01

Full Text Available Background: To determine the morphological specifications of the bird schistosomes cercaria from Lymnaea gedrosiana and to detect the surface carbohydrates as receptors for host lectins in the host-parasite relationship systems such as avian schistosomiasis and human cercarial dermatitis. Methods: One hundred ninety two snails collected from Dezful areas in Khuzestan Province, in the south west of Iran, during 2005-2006 were examined for cercariae using shedding and crushing methods. In addition, surface carbohydrates on the cercariae were detected by lentil (Lens culinaris lectins. Results: From the total number of Lymnaea gedrosiana, which examined for bird schistosomes cercaria, 9(4% snails were found to be infected with furcocercus cercaria of the bird schistosomes (probably Gigantobilharzia sp.. Mannose monosaccharide CH2OH (CHOH4CHO as surface carbohydrate was also detected on the cercariae. Conclusion: Mannose carbohydrate on these cercariae may be used as receptor by lectins.

Cerebral non-oxidative carbohydrate consumption in humans driven by adrenaline

DEFF Research Database (Denmark)

Seifert, Thomas S; Brassard, Patrice; Jørgensen, Thomas B

2009-01-01

infusion (P glucose (P neurons an abundant provision......During brain activation, the decrease in the ratio between cerebral oxygen and carbohydrate uptake (6 O(2)/(glucose + (1)/(2) lactate); the oxygen-carbohydrate index, OCI) is attenuated by the non-selective beta-adrenergic receptor antagonist propranolol, whereas OCI remains unaffected by the beta...... kg(-1) min(-1) i.v. for 20 min) on the arterial to internal jugular venous concentration differences (a-v diff) of O(2), glucose and lactate in healthy humans. Adrenaline (n = 10) increased the arterial concentrations of O(2), glucose and lactate (P glucose...

The effect of fermentable carbohydrate on sporulation and butanol production by Clostridium acetobutylicum P262

Energy Technology Data Exchange (ETDEWEB)

Awang, G.M.; Ingledew, W.M.; Jones, G.A. (Saskatchewan Univ., Saskatoon, SK (Canada). Dept. of Applied Microbiology and Food Science)

1992-10-01

This study was conducted to determine whether or not a variation in the type of carbohydrate fermented by Clostridium acetobutylicum could be exploited to inhibit sporulation during the butanol-producing phase of fermentation and thus enhance butanol production. C. acetobutylicum P262 was found to ferment a wide variety of carbohydrates, but butanol production was not necessarily enhanced when percentage sporulation was low. Butanol concentration was more related to the total amount of acidic end-products (acetic and butyric acid) reutilized by the microorganism for solvent production and to the type and amount of carbohydrate utilized. Fermentation of cellobiose led to conditions resulting in complete acid reutilization and the highest butanol concentration (10.4-10.6 g/l). In cultures containing a mixture of glucose and cellobiose, glucose repression of cellobiose utilization resulted in lower butanol concentrations (6.6-7.5 g/l). Sporulation was dependent on the type of carbohydrate utilized by the microorgamism. Glucose had a greater enhancing effect on the sporulation process (22-42%) than starch (9-12%) or cellobiose (22-34%). It was concluded that whereas the type of carbohydrate fermented has a specific effect on the extent of sporulation of a culture, conditions of low sporulation did not enhance butanol concentration unless carbohydrate utilization and the reutilization of acidic products were high. (orig.).

Metabolic Effects of the Very-Low-Carbohydrate Diets: Misunderstood "Villains" of Human Metabolism

Directory of Open Access Journals (Sweden)

Manninen Anssi H

2004-12-01

Full Text Available Abstract During very low carbohydrate intake, the regulated and controlled production of ketone bodies causes a harmless physiological state known as dietary ketosis. Ketone bodies flow from the liver to extra-hepatic tissues (e.g., brain for use as a fuel; this spares glucose metabolism via a mechanism similar to the sparing of glucose by oxidation of fatty acids as an alternative fuel. In comparison with glucose, the ketone bodies are actually a very good respiratory fuel. Indeed, there is no clear requirement for dietary carbohydrates for human adults. Interestingly, the effects of ketone body metabolism suggest that mild ketosis may offer therapeutic potential in a variety of different common and rare disease states. Also, the recent landmark study showed that a very-low-carbohydrate diet resulted in a significant reduction in fat mass and a concomitant increase in lean body mass in normal-weight men. Contrary to popular belief, insulin is not needed for glucose uptake and utilization in man. Finally, both muscle fat and carbohydrate burn in an amino acid flame.

Sulfated N-linked carbohydrate chains in porcine thyroglobulin

NARCIS (Netherlands)

Vliegenthart, J.F.G.; Kamerling, J.P.; Rijkse, I.; Maas, A.A.M.; Kuik, J.A. van

1988-01-01

N-linked carbohydrate chains of porcine thyroglobulin were released by the hydrazinolysis procedure. The resulting mixture of oligosaccharide-alditols was fractionated by high-voltage paper electrophoresis, the acidic fractions were further separated by high-performance liquid chromatography on

Structural Basis for Carbohydrate Recognition and Anti-inflammatory Modulation by Gastrointestinal Nematode Parasite Toxascaris leonina Galectin*

Science.gov (United States)

Hwang, Eun Young; Jeong, Mi Suk; Park, Sang Kyun; Ha, Sung Chul; Yu, Hak Sun; Jang, Se Bok

2016-01-01

Toxascaris leonina galectin (Tl-gal) is a galectin-9 homologue protein isolated from an adult worm of the canine gastrointestinal nematode parasite, and Tl-gal-vaccinated challenge can inhibit inflammation in inflammatory bowel disease-induced mice. We determined the first X-ray structures of full-length Tl-gal complexes with carbohydrates (lactose, N-acetyllactosamine, lacto-N-tetraose, sialyllactose, and glucose). Bonds were formed on concave surfaces of both carbohydrate recognition domains (CRDs) in Tl-gal. All binding sites were found in the HXXXR and WGXEER motifs. Charged Arg61/Arg196 and Glu80/Glu215 on the conserved motif of Tl-gal N-terminal CRD and C-terminal CRD are critical amino acids for recognizing carbohydrate binding, and the residues can affect protein folding and structure. The polar amino acids His, Asn, and Trp are also important residues for the interaction with carbohydrates through hydrogen bonding. Hemagglutination activities of Tl-gal were inhibited by interactions with carbohydrates and mutations. We found that the mutation of Tl-gal (E80A/E215A) at the carbohydrate binding region induced protein aggregation and could be caused in many diseases. The short linker region between the N-terminal and C-terminal CRDs of Tl-gal was very stable against proteolysis and maintained its biological activity. This structural information is expected to elucidate the carbohydrate recognition mechanism of Tl-gal and improve our understanding of anti-inflammatory mediators and modulators of immune response. PMID:27742836

Click-generated triazole based ferrocene-carbohydrate bioconjugates

Indian Academy of Sciences (India)

carbohydrate bioconjugates, 2,. C46H56O20N6Fe and 3, C28H33O10N3Fe were designed and synthesized in good yields. Both the compounds,. 2 and 3, behave as very selective and sensitive chromogenic and electrochemical chemosensor for Cu2+ ...

Carbohydrates and gibberellins relationship in potato tuberization

Czech Academy of Sciences Publication Activity Database

Ševčíková, H.; Mašková, P.; Tarkowská, Danuše; Mašek, T.; Lipavská, H.

2017-01-01

Roč. 214, JUL (2017), s. 53-63 ISSN 0176-1617 R&D Projects: GA ČR GA14-34792S Institutional support: RVO:61389030 Keywords : Carbohydrate distribution * Gibberellin * Photoautotrophic cultivation * Potato * Tuberization Subject RIV: CB - Analytical Chemistry, Separation OBOR OECD: Plant sciences, botany Impact factor: 3.121, year: 2016

The role of carbohydrates in the radioimmunoassay of human low-molecular-mass kininogen

International Nuclear Information System (INIS)

Turpeinen, U.; Kaerkkaeinen, T.

1985-01-01

The immunoreactivity of human low-molecular-mass kininogen from Cohn plasma fraction IV was investigated after deglycosylations and carbohydrate modifications by radioimmunoassay using the conformation-specific antiserum. Removal of all sialic acids, 44% of amino sugars and 63% of neutral sugars did not alter the immunoreactivity of the protein but the periodate-treated concanavalin A fractions showed strikingly diminished immunoreactivity. A conformational change could account for the observed effect of periodate on the decreased reactivity of the protein in radioimmunoassay. Externally added carbohydrates had no effect on immunoreactivity. The results suggest that the carbohydrate part of kininogen is not involved in the immunoreactivity although it accounts for the observed lectin-binding heterogeneity. (Auth.)

Comparative effects of several simple carbohydrates on erythrocyte insulin receptors in obese subjects.

Science.gov (United States)

Rizkalla, S W; Baigts, F; Fumeron, F; Rabillon, B; Bayn, P; Ktorza, A; Spielmann, D; Apfelbaum, M

1986-09-01

The effects of simple carbohydrates on erythrocyte insulin receptors, plasma insulin and plasma glucose were studied during four hypocaloric, hyperproteic, diets. One diet contained no carbohydrate; the other three contained 36 g of either glucose, galactose or fructose. These diets were given for a 14-day period to groups of moderately obese subjects. The hypocaloric carbohydrate-free diet produced a decrease in plasma insulin and glucose concentrations concomitant with an increase in the number of insulin receptors. A similar increase in insulin receptor number was found when the diet was supplemented with glucose or galactose, but not with fructose. The presence of fructose in the diet prevented any increase in insulin receptor number.

High-glycemic index carbohydrates abrogate the antiobesity effect of fish oil in mice

DEFF Research Database (Denmark)

Hao, Qin; Lillefosse, Haldis Haukås; Fjære, Even

2012-01-01

Fish oil rich in n-3 polyunsaturated fatty acids is known to attenuate diet-induced obesity and adipose tissue inflammation in rodents. Here we aimed to investigate whether different carbohydrate sources modulated the antiobesity effects of fish oil. By feeding C57BL/6J mice isocaloric high-fat d...... metabolic effects of fish oil by demonstrating that high-GI carbohydrates attenuate the antiobesity effects of fish oil.......Fish oil rich in n-3 polyunsaturated fatty acids is known to attenuate diet-induced obesity and adipose tissue inflammation in rodents. Here we aimed to investigate whether different carbohydrate sources modulated the antiobesity effects of fish oil. By feeding C57BL/6J mice isocaloric high...

Protein-carbohydrate complex reveals circulating metastatic cells in a microfluidic assay

KAUST Repository

Simone, Giuseppina

2013-02-11

Advances in carbohydrate sequencing technologies reveal the tremendous complexity of the glycome and the role that glycomics might have to bring insight into the biological functions. Carbohydrate-protein interactions, in particular, are known to be crucial to most mammalian physiological processes as mediators of cell adhesion and metastasis, signal transducers, and organizers of protein interactions. An assay is developed here to mimic the multivalency of biological complexes that selectively and sensitively detect carbohydrate-protein interactions. The binding of β-galactosides and galectin-3 - a protein that is correlated to the progress of tumor and metastasis - is examined. The efficiency of the assay is related to the expression of the receptor while anchoring to the interaction\\'s strength. Comparative binding experiments reveal molecular binding preferences. This study establishes that the assay is robust to isolate metastatic cells from colon affected patients and paves the way to personalized medicine. Copyright © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Protein-carbohydrate complex reveals circulating metastatic cells in a microfluidic assay

KAUST Repository

Simone, Giuseppina; Malara, Natalia Maria; Trunzo, Valentina; Perozziello, Gerardo; Neužil, Pavel; Francardi, Marco; Roveda, Laura; Renne, Maria; Prati, Ubaldo; Mollace, Vincenzo; Manz, Andreas; Di Fabrizio, Enzo M.

2013-01-01

Advances in carbohydrate sequencing technologies reveal the tremendous complexity of the glycome and the role that glycomics might have to bring insight into the biological functions. Carbohydrate-protein interactions, in particular, are known to be crucial to most mammalian physiological processes as mediators of cell adhesion and metastasis, signal transducers, and organizers of protein interactions. An assay is developed here to mimic the multivalency of biological complexes that selectively and sensitively detect carbohydrate-protein interactions. The binding of β-galactosides and galectin-3 - a protein that is correlated to the progress of tumor and metastasis - is examined. The efficiency of the assay is related to the expression of the receptor while anchoring to the interaction's strength. Comparative binding experiments reveal molecular binding preferences. This study establishes that the assay is robust to isolate metastatic cells from colon affected patients and paves the way to personalized medicine. Copyright © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Method Optimization for Rapid Measurement of Carbohydrates in Plasma by Liquid Chromatography Tandem Mass Spectrometry

International Nuclear Information System (INIS)

Nguyen, Ductoan; Yu, Jondong; Mho, Sunil; Lee, Gwang; Lee, Haelee; Paik, Manjeong; Yee, Sungtae

2013-01-01

In conclusion, the developed HPLC coupled with ESI-MS was a powerful technique for the separation and characterization of carbohydrates by either SIM or MRM mode. The present method will be useful for the monitoring of carbohydrate profile in biological fluids from various diseases including diabetic ketoacidosis, hypoglycemia and hyperosmolar coma. Carbohydrates are one of the most abundant classes of organic compounds in nature, which not only constitute complex biomolecules in human and animals but are also distributed in plants and bacteria

Ingestion of High Molecular Weight Carbohydrate Enhances Subsequent Repeated Maximal Power: A Randomized Controlled Trial.

Directory of Open Access Journals (Sweden)

Jonathan M Oliver

Full Text Available Athletes in sports demanding repeat maximal work outputs frequently train concurrently utilizing sequential bouts of intense endurance and resistance training sessions. On a daily basis, maximal work within subsequent bouts may be limited by muscle glycogen availability. Recently, the ingestion of a unique high molecular weight (HMW carbohydrate was found to increase glycogen re-synthesis rate and enhance work output during subsequent endurance exercise, relative to low molecular weight (LMW carbohydrate ingestion. The effect of the HMW carbohydrate, however, on the performance of intense resistance exercise following prolonged-intense endurance training is unknown. Sixteen resistance trained men (23±3 years; 176.7±9.8 cm; 88.2±8.6 kg participated in a double-blind, placebo-controlled, randomized 3-way crossover design comprising a muscle-glycogen depleting cycling exercise followed by ingestion of placebo (PLA, or 1.2 g•kg•bw-1 of LMW or HMW carbohydrate solution (10% with blood sampling for 2-h post-ingestion. Thereafter, participants performed 5 sets of 10 maximal explosive repetitions of back squat (75% of 1RM. Compared to PLA, ingestion of HMW (4.9%, 90%CI 3.8%, 5.9% and LMW (1.9%, 90%CI 0.8%, 3.0% carbohydrate solutions substantially increased power output during resistance exercise, with the 3.1% (90% CI 4.3, 2.0% almost certain additional gain in power after HMW-LMW ingestion attributed to higher movement velocity after force kinematic analysis (HMW-LMW 2.5%, 90%CI 1.4, 3.7%. Both carbohydrate solutions increased post-exercise plasma glucose, glucoregulatory and gut hormones compared to PLA, but differences between carbohydrates were unclear; thus, the underlying mechanism remains to be elucidated. Ingestion of a HMW carbohydrate following prolonged intense endurance exercise provides superior benefits to movement velocity and power output during subsequent repeated maximal explosive resistance exercise. This study was registered

Normal Roles for Dietary Fructose in Carbohydrate Metabolism

Directory of Open Access Journals (Sweden)

Maren R. Laughlin

2014-08-01

Full Text Available Although there are many well-documented metabolic effects linked to the fructose component of a very high sugar diet, a healthy diet is also likely to contain appreciable fructose, even if confined to that found in fruits and vegetables. These normal levels of fructose are metabolized in specialized pathways that synergize with glucose at several metabolic steps. Glucose potentiates fructose absorption from the gut, while fructose catalyzes glucose uptake and storage in the liver. Fructose accelerates carbohydrate oxidation after a meal. In addition, emerging evidence suggests that fructose may also play a role in the secretion of insulin and GLP-1, and in the maturation of preadipocytes to increase fat storage capacity. Therefore, fructose undergoing its normal metabolism has the interesting property of potentiating the disposal of a dietary carbohydrate load through several routes.

Carbohydrate sources of microfouling material developed on aluminium and stainless steel panels

Digital Repository Service at National Institute of Oceanography (India)

Bhosle, N.B.; Sankaran, P.D.; Wagh, A.B.

. pp. 151 -164 Reprints available directly from the pUblishcr Photocopying permitted by license only © 1990 Harwood Academic Publishers GmbH Printed in Great Britain CARBOHYDRATE SOURCES OF MICROFOULING MATERIAL DEVELOPED ON ALUMINIUM AND STAINLESS... plant material and grasses appear to be the major sources contributing to the carbohydrates ofthe microfouling material. KEY WORDS: Carbohydratc. microfouling. sources, aluminium, stainless steel, Arabian Sea, Bay of Hengal. INTRODUCTION Solid surfaces...

[Effects of progestogens on the metabolism of lipids and carbohydrates. Practical consequences (author's transl)].

Science.gov (United States)

Ghéron, G

Estrogens which are one of the components of contraceptive less than pills greater than are incriminated in many cardiovascular accidents. These occur as a result of metabolic disorders (involving lipids and carbohydrates), of modifications in coagulation factors, etc. The possible influence of progestogens was ignored for a long time. The widespread use of these compounds, prescribed for contraception as well as during hormonal replacement therapy for absolute or relative luteinic insufficiency, makes careful monitoring of lipid and carbohydrate metabolism imperative. This position is strengthened by a preliminary review of the literature which leads to several conclusions concerning lipid and carbohydrate metabolism.

Simple vs. Complex Carbohydrate Dietary Patterns and the Global Overweight and Obesity Pandemic.

Science.gov (United States)

Ferretti, Fabrizio; Mariani, Michele

2017-10-04

Nowadays, obesity and being overweight are among the major global health concerns. Many, diet-related diseases impose high tangible and intangible costs, and threaten the sustainability of health-care systems worldwide. In this study, we model, at the macroeconomic level, the impact of energy intake from different types of carbohydrates on the population's BMI (body mass index). We proceed in three steps. First, we develop a framework to analyse both the consumption choices between simple and complex carbohydrates and the effects of these choices on people health conditions. Second, we collect figures for 185 countries (over the period 2012-2014) regarding the shares of simple (sugar and sweetener) and complex (cereal) carbohydrates in each country's total dietary energy supply. Third, we use regression techniques to: (1) estimate the impact of these shares on the country's prevalence of obesity and being overweight; (2) compute for each country an indicator of dietary pattern based on the ratio between simple and complex carbohydrates, weighted by their estimated effects on the prevalence of obesity and being overweight; and (3) measure the elasticity of the prevalence of obesity and being overweight with respect to changes in both carbohydrate dietary pattern and income per capita. We find that unhealthy eating habits and the associated prevalence of excessive body fat accumulation tend to behave as a 'normal good' in low, medium- and high-HDI (Human Development Index) countries, but as an 'inferior good' in very high-HDI countries.

A low-carbohydrate, ketogenic diet versus a low-fat diet to treat obesity and hyperlipidemia: a randomized, controlled trial.

Science.gov (United States)

Yancy, William S; Olsen, Maren K; Guyton, John R; Bakst, Ronna P; Westman, Eric C

2004-05-18

Low-carbohydrate diets remain popular despite a paucity of scientific evidence on their effectiveness. To compare the effects of a low-carbohydrate, ketogenic diet program with those of a low-fat, low-cholesterol, reduced-calorie diet. Randomized, controlled trial. Outpatient research clinic. 120 overweight, hyperlipidemic volunteers from the community. Low-carbohydrate diet (initially, carbohydrate daily) plus nutritional supplementation, exercise recommendation, and group meetings, or low-fat diet (fat, low-carbohydrate diet group than the low-fat diet group completed the study (76% vs. 57%; P = 0.02). At 24 weeks, weight loss was greater in the low-carbohydrate diet group than in the low-fat diet group (mean change, -12.9% vs. -6.7%; P fat mass (change, -9.4 kg with the low-carbohydrate diet vs. -4.8 kg with the low-fat diet) than fat-free mass (change, -3.3 kg vs. -2.4 kg, respectively). Compared with recipients of the low-fat diet, recipients of the low-carbohydrate diet had greater decreases in serum triglyceride levels (change, -0.84 mmol/L vs. -0.31 mmol/L [-74.2 mg/dL vs. -27.9 mg/dL]; P = 0.004) and greater increases in high-density lipoprotein cholesterol levels (0.14 mmol/L vs. -0.04 mmol/L [5.5 mg/dL vs. -1.6 mg/dL]; P low-density lipoprotein cholesterol level did not differ statistically (0.04 mmol/L [1.6 mg/dL] with the low-carbohydrate diet and -0.19 mmol/L [-7.4 mg/dL] with the low-fat diet; P = 0.2). Minor adverse effects were more frequent in the low-carbohydrate diet group. We could not definitively distinguish effects of the low-carbohydrate diet and those of the nutritional supplements provided only to that group. In addition, participants were healthy and were followed for only 24 weeks. These factors limit the generalizability of the study results. Compared with a low-fat diet, a low-carbohydrate diet program had better participant retention and greater weight loss. During active weight loss, serum triglyceride levels decreased more and high

Direct catalytic transformation of carbohydrates into 5-ethoxymethylfurfural with acid–base bifunctional hybrid nanospheres

DEFF Research Database (Denmark)

Li, Hu; Khokarale, Santosh Govind; Kotni, Ramakrishna

2014-01-01

carbohydrates. A high EMF yield of 76.6%, 58.5%, 42.4%, and 36.5% could be achieved, when fructose, inulin, sorbose, and sucrose were used as starting materials, respectively. Although, the acid–base bifunctional nanocatalysts were inert for synthesis of EMF from glucose based carbohydrates, ethyl...

Design, synthesis and evaluation of 2-deoxy-2-iodovinyl-branched carbohydrates as potential brain imaging agents

International Nuclear Information System (INIS)

Goodman, M.M.; Callahan, A.P.; Knapp, F.F. Jr.

1986-01-01

Radioiodinated carbohydrates such as 2-deoxy-2-iodo-D-glucose and 3-deoxy-3-iodo-D-glucose undergo facile chemical or in vivo deiodination which precludes their use as radiotracers of glucose metabolism in tissues. To overcome the problems resulting from in vivo deiodination, we explored the concept of stabilizing radioiodide on a model carbohydrate, (E)-C-3-iodovinyl-D-allose as an iodovinyl moiety. This agent did not exhibit brain specificity but showed low in vivo deiodination which demonstrated for the first time that radioiodide can be stabilized on a carbohydrate. The goal of this study was to develop a deoxy-branched carbohydrate with radioiodide stabilized as a vinyliodide with the objective of achieving high brain uptake. (author)

Crystallization of carbohydrate oxidase from Microdochium nivale

Czech Academy of Sciences Publication Activity Database

Dušková, Jarmila; Dohnálek, Jan; Skálová, Tereza; Ostergaard, L. H.; Fuglsang, C. C.; Kolenko, Petr; Štěpánková, Andrea; Hašek, Jindřich

2009-01-01

Roč. 65, č. 6 (2009), s. 638-640 ISSN 1744-3091 R&D Projects: GA AV ČR IAA500500701; GA ČR GA305/07/1073 Institutional research plan: CEZ:AV0Z40500505 Keywords : carbohydrate oxidase * crystallization * data processing Subject RIV: CD - Macromolecular Chemistry Impact factor: 0.551, year: 2009

Concentrating carbohydrates before sleep improves feeding regulation and metabolic and inflammatory parameters in mice.

Science.gov (United States)

Sofer, Sigal; Eliraz, Abraham; Madar, Zecharia; Froy, Oren

2015-10-15

New evidance highlights the importance of food timing. Recently, we showed that a low-calorie diet with carbohydrates eaten mostly at dinner changed diurnal hormone secretion and led to greater weight loss and improved metabolic status in obese people. Herein, we set out to test whether concentrated-carbohydrates diet (CCD), in which carbohydrates are fed only before sleep, leads to an improved metabolic status in mouse hypothalamus and peripheral tissues. Diet-induced obese mice were given concentrated or distributed carbohydrate diet for 6 weeks. Obese mice fed CCD ate 8.3% less, were 9.3% leaner and had 39.7% less fat mass. Leptin, ghrelin and adiponectin displayed altered secretion. In addition, these mice exhibited an improved biochemical and inflammatory status. In the hypothalamus, anorexigenic signals were up-regulated and orexigenic signals were down-regulated. In peripheral tissues, CCD promoted adiponectin signaling, repressed gluconeogenesis, enhanced lipid oxidation and lowered inflammation, thus ameliorating the major risk factors of obesity. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

Transformation of acetate carbon into carbohydrate and amino acid metabilites during decomposition in soil

DEFF Research Database (Denmark)

Sørensen, Lasse Holst; Paul, E. A.

1971-01-01

Carbon-14-labelled acetate was added to a heavy clay soil of pH 7.6 to study the transformation of acetate carbon into carbohydrate and amino acid metabolites during decomposition. The acetate was totally metabolized after 6 days of incubation at 25°C when 70% of the labelled carbon had been...... evolved as CO2. Maximum incorporation of trace-C into the various organic fractions was observed after 4 days when 19% of residual, labelled carbon in the soil was located in carbohydrates, 29 % in amino acids and 21 % in the insoluble residue of the soil. The curves showing the amounts of labelled carbon...... days of incubation, 2.2% of the labelled carbon originally added to the soil was located in carbohydrate metabolites, 7% in amino acid metabolites and 5% in the insoluble residue. The carbon in these fractions accounted for 77% of the total, residual, labelled carbon in the soil; 12% in carbohydrates...

Influence of different cultivation methods on carbohydrate and lipid compositions and digestibility of energy of fruits and vegetables

DEFF Research Database (Denmark)

Jørgensen, Henry; Knudsen, Knud Erik Bach; Lauridsen, Charlotte

2012-01-01

of carbohydrates and fatty acids of fruits and vegetables. The objective was to investigate the influence of organic and conventional cultivation systems on the carbohydrate and fatty acid composition and digestibility of the energy of apple, carrot, kale, pea, potato, and rape seed oil. RESULTS: Carbohydrate...

Unlimited energy, restricted carbohydrate diet improves lipid parameters in obese children.

Science.gov (United States)

Dunlap, Brian S; Bailes, James R

2008-03-01

Childhood obesity is a leading health concern. We have previously demonstrated the effectiveness of a restricted-carbohydrate, unlimited energy diet for weight reduction in elementary school-aged children. To our knowledge, there are no studies that have looked at the effect of this diet on lipid profiles in elementary school-aged children. Therefore, the objective of this pilot study was to examine the effect of a restricted-carbohydrate, unlimited protein, unlimited energy diet on lipid profiles in obese children 6 to 12 years of age. Overweight children (body mass index >97%) referred to our obesity clinic were treated with a restricted-carbohydrate (unlimited protein, and unlimited energy diet. Weight, height, body mass index, and fasting lipid profiles were obtained at baseline and at 10 weeks on each patient. Twenty-seven patients were enrolled in our study, with a total of 18 patients returning for our 10 week follow-up (67%). The study group included 10 males and 8 females, with an age range of 6 to 12 years. Both total serum cholesterol and triglyceride levels showed a significant reduction; 24.2 (P = 0.018) and 56.9 (P = 0.015) mg/dL, respectively. We have demonstrated a significant decrease in total cholesterol and triglycerides in elementary school-aged children after 10 weeks of a restricted-carbohydrate, unlimited protein, and unlimited energy diet. We suggest that this diet may decrease cardiovascular risk factors in obese children. Long-term studies will be needed to substantiate these data.

Pengaruh penerapan carbohydrate loading modifikasi terhadap kesegaran jasmani atlet sepak bola

Directory of Open Access Journals (Sweden)

Bayu Febri Utoro

2016-06-01

Full Text Available Background: The reduction of glycogen stores gradually during sports activities affect the performance of athletes. Carbohydrate loading is a method that aims to increase the glycogen stores are expected to delay fatigue and prevent hypoglycemia at the time of the match Purpose: The purpose of this study was to verify the effect of modification carbohydrate loading to the physical fitness and some indicators of nutritional status soccer athletes Methods: Experimental studies with approaches one group pre and post test design on 23 athletes aged 14-20 years in Diklat Sepak Bola Bintang Pelajar Semarang Regency  in July 2011. During one week the subjects were given a high carbohydrate intake approximately 70% of the total energy requirement (protein and fat are given to normal and soccer practice programmed with moderate intensity in the first three days and continued the intensity of light at the second of three days. Measurements included weight, height, percent body fat, lean body mass, blood glucose levels and physical fitness with Asian Committee on the Standarization of Physical Fitness Test (ACSPFT method Results: There were significant differences  of physical fitness, physical fitness components (speed and cardiorespiratory endurance, body mass index, percent fat, lean body mass and blood glucose levels before and after treatment with p <0.05 Conclusion: Modified carbohydrate loading effected on physical fitness of soccer athletes. Fat mass and lean body mass to be the most influence factors on physical fitness

Genetic and environmental control of seasonal carbohydrate dynamics in trees of diverse Pinus sylvestris populations.

Science.gov (United States)

Oleksyn, J.; Zytkowiak, R.; Karolewski, P.; Reich, P. B.; Tjoelker, M. G.

2000-06-01

We explored environmental and genetic factors affecting seasonal dynamics of starch and soluble nonstructural carbohydrates in needle and twig cohorts and roots of Scots pine (Pinus sylvestris L.) trees of six populations originating between 49 degrees and 60 degrees N, and grown under common garden conditions in western Poland. Trees of each population were sampled once or twice per month over a 3-year period from age 15 to 17 years. Based on similarity in starch concentration patterns in needles, two distinct groups of populations were identified; one comprised northern populations from Sweden and Russia (59-60 degrees N), and another comprised central European populations from Latvia, Poland, Germany and France (49-56 degrees N). Needle starch concentrations of northern populations started to decline in late spring and reached minimum values earlier than those of central populations. For all populations, starch accumulation in spring started when minimum air temperature permanently exceeded 0 degrees C. Starch accumulation peaked before bud break and was highest in 1-year-old needles, averaging 9-13% of dry mass. Soluble carbohydrate concentrations were lowest in spring and summer and highest in autumn and winter. There were no differences among populations in seasonal pattern of soluble carbohydrate concentrations. Averaged across all populations, needle soluble carbohydrate concentrations increased from about 4% of needle dry mass in developing current-year needles, to about 9% in 1- and 2-year-old needles. Root carbohydrate concentration exhibited a bimodal pattern with peaks in spring and autumn. Northern populations had higher concentrations of fine-root starch in spring and autumn than central populations. Late-summer carbohydrate accumulation in roots started only after depletion of starch in needles and woody shoots. We conclude that Scots pine carbohydrate dynamics depend partially on inherited properties that are probably related to phenology of root

A holistic view of dietary carbohydrate utilization in lobster: digestion, postprandial nutrient flux, and metabolism.

Science.gov (United States)

Rodríguez-Viera, Leandro; Perera, Erick; Casuso, Antonio; Perdomo-Morales, Rolando; Gutierrez, Odilia; Scull, Idania; Carrillo, Olimpia; Martos-Sitcha, Juan A; García-Galano, Tsai; Mancera, Juan Miguel

2014-01-01

Crustaceans exhibit a remarkable variation in their feeding habits and food type, but most knowledge on carbohydrate digestion and utilization in this group has come from research on few species. The aim of this study was to make an integrative analysis of dietary carbohydrate utilization in the spiny lobster Panulirus argus. We used complementary methodologies such as different assessments of digestibility, activity measurements of digestive and metabolic enzymes, and post-feeding flux of nutrients and metabolites. Several carbohydrates were well digested by the lobster, but maize starch was less digestible than all other starches studied, and its inclusion in diet affected protein digestibility. Most intense hydrolysis of carbohydrates in the gastric chamber of lobster occurred between 2-6 h after ingestion and afterwards free glucose increased in hemolymph. The inclusion of wheat in diet produced a slow clearance of glucose from the gastric fluid and a gradual increase in hemolymph glucose. More intense hydrolysis of protein in the gastric chamber occurred 6-12 h after ingestion and then amino acids tended to increase in hemolymph. Triglyceride concentration in hemolymph rose earlier in wheat-fed lobsters than in lobsters fed other carbohydrates, but it decreased the most 24 h later. Analyses of metabolite levels and activities of different metabolic enzymes revealed that intermolt lobsters had a low capacity to store and use glycogen, although it was slightly higher in wheat-fed lobsters. Lobsters fed maize and rice diets increased amino acid catabolism, while wheat-fed lobsters exhibited higher utilization of fatty acids. Multivariate analysis confirmed that the type of carbohydrate ingested had a profound effect on overall metabolism. Although we found no evidence of a protein-sparing effect of dietary carbohydrate, differences in the kinetics of their digestion and absorption impacted lobster metabolism determining the fate of other nutrients.

A holistic view of dietary carbohydrate utilization in lobster: digestion, postprandial nutrient flux, and metabolism.

Directory of Open Access Journals (Sweden)

Leandro Rodríguez-Viera

Full Text Available Crustaceans exhibit a remarkable variation in their feeding habits and food type, but most knowledge on carbohydrate digestion and utilization in this group has come from research on few species. The aim of this study was to make an integrative analysis of dietary carbohydrate utilization in the spiny lobster Panulirus argus. We used complementary methodologies such as different assessments of digestibility, activity measurements of digestive and metabolic enzymes, and post-feeding flux of nutrients and metabolites. Several carbohydrates were well digested by the lobster, but maize starch was less digestible than all other starches studied, and its inclusion in diet affected protein digestibility. Most intense hydrolysis of carbohydrates in the gastric chamber of lobster occurred between 2-6 h after ingestion and afterwards free glucose increased in hemolymph. The inclusion of wheat in diet produced a slow clearance of glucose from the gastric fluid and a gradual increase in hemolymph glucose. More intense hydrolysis of protein in the gastric chamber occurred 6-12 h after ingestion and then amino acids tended to increase in hemolymph. Triglyceride concentration in hemolymph rose earlier in wheat-fed lobsters than in lobsters fed other carbohydrates, but it decreased the most 24 h later. Analyses of metabolite levels and activities of different metabolic enzymes revealed that intermolt lobsters had a low capacity to store and use glycogen, although it was slightly higher in wheat-fed lobsters. Lobsters fed maize and rice diets increased amino acid catabolism, while wheat-fed lobsters exhibited higher utilization of fatty acids. Multivariate analysis confirmed that the type of carbohydrate ingested had a profound effect on overall metabolism. Although we found no evidence of a protein-sparing effect of dietary carbohydrate, differences in the kinetics of their digestion and absorption impacted lobster metabolism determining the fate of other

Effect of Carbohydrate Supplementation on Investment into Offspring Number, Size, and Condition in a Social Insect.

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Bill D Wills

Full Text Available Resource availability can determine an organism's investment strategies for growth and reproduction. When nutrients are limited, there are potential tradeoffs between investing into offspring number versus individual offspring size. In social insects, colony investment in offspring size and number may shift in response to colony needs and the availability of food resources. We experimentally manipulated the diet of a polymorphic ant species (Solenopsis invicta to test how access to the carbohydrate and amino acid components of nectar resources affect colony investment in worker number, body size, size distributions, and individual percent fat mass. We reared field-collected colonies on one of four macronutrient treatment supplements: water, amino acids, carbohydrates, and amino acid and carbohydrates. Having access to carbohydrates nearly doubled colony biomass after 60 days. This increase in biomass resulted from an increase in worker number and mean worker size. Access to carbohydrates also altered worker body size distributions. Finally, we found a negative relationship between worker number and size, suggesting a tradeoff in colony investment strategies. This tradeoff was more pronounced for colonies without access to carbohydrate resources. The monopolization of plant-based resources has been implicated in the ecological success of ants. Our results shed light on a possible mechanism for this success, and also have implications for the success of introduced species. In addition to increases in colony size, our results suggest that having access to plant-based carbohydrates can also result in larger workers that may have better individual fighting ability, and that can withstand greater temperature fluctuations and periods of food deprivation.

THE RELATIONSHIP BETWEEN ALTITUDES AND THE CONTENTS OF PROTEIN, CARBOHYDRATES, LIPIDS OF PUMPKIN (Cucurbita moschata

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Suranto Tjiptowibisono

2015-02-01

Full Text Available Cucurbita moschata or pumpkin can be used as an alternative food mainly due to its carbohydrate content, and it is very easy to grow in many different habitats. The objective of this research was to evaluate the biochemical contents of C. moschata based on the altitudes and also to examine whether any relationship between the environmental conditions and protein, carbohydrate and lipid contents. Proximate analysis was used for statistical consideration of the results obtained. Chemical analysis was conducted by using mesocarp of pumpkin after cleaning, peeling and removing seeds from the center of fruits. Kjedahl and soxhlet methods were used to look at the content of protein and lipid respectively. Meanwhile, the method of difference was employed to measure the percentage of carbohydrates. Although there was no significant relationship between the biochemical contents and the environmental conditions, it was recorded that plants grown at higher altitudes with high soil pH and air temperature tended to have higher protein, carbohydrate and lipid contents, compared to that of higher soil moisture. This results showed that the highest biochemical contents of protein, carbohydrate and lipid of two varieties C. moschata were evident at the lowest altitude.

Investigation of a New Spectrophotometric Method for the analysis of carbohydrates using glucose as model

International Nuclear Information System (INIS)

Hussain, Z.; Ali, A.; Shah, N.U.; Khan, K.M.

2013-01-01

Carbohydrates are biomolecule of significant importance. Its analysis is of prime importance in the clinical investigations, delivery of medicines and quality control operations of food and fuel products. Based on its importance a novel spectrophotometric method was investigated for the trace analysis of carbohydrates using glucose as model carbohydrate. This method is based on glucosazation followed by oxidation of the glucosazone with acidified iron (III) chloride. Oxidation of the glucsazone is necessary for enhancing the color intensity and optimum conditions were investigated for the process. All the absorbance measurements were carried out using 390 nm as gamma max. The ratio of the reactants was 1: 1.5: 0.1 mole for the glucose, phenyl hydrazine and iron (III) chloride. This method was used for the analysis of carbohydrates in real samples from plants, industrial products, blood and urine using glucose as reference. (author)

Linking Bacillus cereus Genotypes and Carbohydrate Utilization Capacity

NARCIS (Netherlands)

Warda, Alicja K.; Siezen, Roland J.; Boekhorst, Jos; Wells-Bennik, Marjon H.J.; Jong, de Anne; Kuipers, Oscar P.; Nierop Groot, Masja N.; Abee, Tjakko

2016-01-01

We characterised carbohydrate utilisation of 20 newly sequenced Bacillus cereus strains isolated from food products and food processing environments and two laboratory strains, B. cereus ATCC 10987 and B. cereus ATCC 14579. Subsequently, genome sequences of these strains were analysed together with

Molar extinction coefficients of some carbohydrates in aqueous ...

Indian Academy of Sciences (India)

of plants and animals, both as structural elements and in the maintenance of functional ... In this paper we report the molar extinction coefficient ε, of carbohydrates ... as the area, which has to be hit by the photons in order to cause interaction.

Affinity labeling of the carbohydrate binding site of the lectin discoidin I using a photoactivatable radioiodinated monosaccharide

International Nuclear Information System (INIS)

Kohnken, R.E.; Berger, E.A.

1987-01-01

N-(4-Azidosalicyl) galactosamine (GalNASA), a photoactivatable, radioiodinatable analog of N-acetylgalactosamine (GalNAc), has been prepared and characterized. The authors have used this reagent for labeling of the carbohydrate binding site of discoidin I, an endogenous lectin produced by Dictyostelium discoideum. GalNASA behaved as a ligand for discoidin I, as judged by its ability to compete in an assay measuring the carbohydrate binding activity of discoidin I. In this assay, it exhibited a K/sub i,app/ of 800 μM, comparable to that of GalNAc. The K/sub i,app/ of GalNASA decreased to 40 μm upon prior photolysis with ultraviolet light. In contrast, N-(4-azidosalicyl) ethanolamine produced no inhibition of carbohydrate binding regardless of photolysis. Covalent labeling of discoidin I with 125 I-GalNASA was entirely dependent upon ultraviolet light. A portion of labeling, representing 40-60% of the total, was sensitive to reagents which were known to inhibit carbohydrate binding by discoidin I, including GalNAc, asialofetuin, and ethyl-enediaminetetraacetic acid. The carbohydrate-sensitive fraction of discoidin I photolabeling with 125 I-GalNASA exhibited a K/sub d/ of 15-40 μM, in agreement with the K/sub i,app/ of prephotolyzed GalNASA observed in the carbohydrate binding assay. Partial proteolytic digestion of photolabeled discoidin I revealed specific fragments whose labeling was completely blocked by GalNAc. This indicated that the location of carbohydrate-sensitive labeling within the structure of discoidin I was restricted. One particular tryptic fragment, Tr1, was examined in detail. These data suggest that Tr1 is derived from the carbohydrate binding site of discoidin I

Impact of advanced and basic carbohydrate counting methods on metabolic control in patients with type 1 diabetes.

Science.gov (United States)

Souto, Débora Lopes; Zajdenverg, Lenita; Rodacki, Melanie; Rosado, Eliane Lopes

2014-03-01

Diets based on carbohydrate counting remain a key strategy for improving glycemic control in patients with type 1 diabetes. However, these diets may promote weight gain because of the flexibility in food choices. The aim of this study was to compare carbohydrate counting methods regarding anthropometric, biochemical, and dietary variables in individuals with type 1 diabetes, as well as to evaluate their knowledge about nutrition. Participants were allocated in basic or advanced groups. After 3 mo of the nutritional counseling, dietary intake, anthropometric variables, lipemia, and glycemic control were compared between groups. A questionnaire regarding carbohydrate counting, sucrose intake, nutritional knowledge, and diabetes and nutrition taboos also was administered. Ten (30%) participants had already used advanced carbohydrate counting before the nutritional counseling and these individuals had a higher body mass index (BMI) (P 1) and waist circumference (WC) (P = 0.01) than others (n = 23; 69.7%). After 3 mo of follow-up, although participants in the advanced group (n = 17; 51.52%) presented higher BMI (P 1) and WC (P = 0.03), those in the basic group (n = 16; 48.48%) showed a higher fat intake (P 1). The majority of participants reported no difficulty in following carbohydrate counting (62.5% and 88% for basic and advanced groups, respectively) and a greater flexibility in terms of food choices (>90% with both methods). Advanced carbohydrate counting did not affect lipemic and glycemic control in individuals with type 1 diabetes, however, it may increase food intake, and consequently the BMI and WC, when compared to basic carbohydrate counting. Furthermore, carbohydrate counting promoted greater food flexibility. Copyright © 2014 Elsevier Inc. All rights reserved.

Design, synthesis and evaluation of 2-deoxy-2-iodovinyl-branched carbohydrates as potential brain imaging agents

International Nuclear Information System (INIS)

Goodman, M.M.; Callahan, A.P.; Knapp, F.F. Jr.

1986-01-01

Radioiodinated carbohydrates such as 2-deoxy-2-iodo-D-glucose and 3-deoxy-3-iodo-D-glucose undergo facile chemical or in vivo deiodination which precludes their use as radiotracers of glucose metabolism in tissues. To overcome the problems resulting from in vivo deiodination, we explored the concept of stabilizing radioiodide on a model carbohydrate, (E)-C-3-iodovinyl-D-allose (10) as an iodovinyl moiety. This agent did not exhibit brain specificity but showed low in vivo deiodination which demonstrated for the first time that radioiodide can be stabilized on a carbohydrate. The goal of this study was to develop a deoxy-branched carbohydrate with radioiodide stabilized as a vinyliodide with the objective of achieving high brain uptake. 10 refs., 1 fig., 1 tab

Design, synthesis and evaluation of 2-deoxy-2-iodovinyl-branched carbohydrates as potential brain imaging agents

Energy Technology Data Exchange (ETDEWEB)

Goodman, M.M.; Callahan, A.P.; Knapp, F.F. Jr.

1986-01-01

Radioiodinated carbohydrates such as 2-deoxy-2-iodo-D-glucose and 3-deoxy-3-iodo-D-glucose undergo facile chemical or in vivo deiodination which precludes their use as radiotracers of glucose metabolism in tissues. To overcome the problems resulting from in vivo deiodination, we explored the concept of stabilizing radioiodide on a model carbohydrate, (E)-C-3-iodovinyl-D-allose (10) as an iodovinyl moiety. This agent did not exhibit brain specificity but showed low in vivo deiodination which demonstrated for the first time that radioiodide can be stabilized on a carbohydrate. The goal of this study was to develop a deoxy-branched carbohydrate with radioiodide stabilized as a vinyliodide with the objective of achieving high brain uptake. 10 refs., 1 fig., 1 tab.

Isocaloric carbohydrate deprivation induces protein catabolism despite a low T3-syndrome in healthy men

NARCIS (Netherlands)

Bisschop, P. H.; Sauerwein, H. P.; Endert, E.; Romijn, J. A.

2001-01-01

Dietary carbohydrate content is a major factor determining endocrine and metabolic regulation. The aim of this study was to evaluate the relation between thyroid hormone levels and metabolic parameters during eucaloric carbohydrate deprivation. We measured thyroid hormone levels, resting energy

Successful Colonization of Lodgepole Pine Trees by Mountain Pine Beetle Increased Monoterpene Production and Exhausted Carbohydrate Reserves.

Science.gov (United States)

Roth, Marla; Hussain, Altaf; Cale, Jonathan A; Erbilgin, Nadir

2018-02-01

Lodgepole pine (Pinus contorta) forests have experienced severe mortality from mountain pine beetle (MPB) (Dendroctonus ponderosae Hopkins) in western North America for the last several years. Although the mechanisms by which beetles kill host trees are unclear, they are likely linked to pine defense monoterpenes that are synthesized from carbohydrate reserves. However, how carbohydrates and monoterpenes interact in response to MPB colonization is unknown. Understanding this relationship could help to elucidate how pines succumb to bark beetle attack. We compared concentrations of individual and total monoterpenes and carbohydrates in the phloem of healthy pine trees with those naturally colonized by MPB. Trees attacked by MPB had nearly 300% more monoterpenes and 40% less carbohydrates. Total monoterpene concentrations were most strongly associated with the concentration of sugars in the phloem. These results suggest that bark beetle colonization likely depletes carbohydrate reserves by increasing the production of carbon-rich monoterpenes, and other carbon-based secondary compounds. Bark beetle attacks also reduce water transport causing the disruption of carbon transport between tree foliage and roots, which restricts carbon assimilation. Reduction in carbohydrate reserves likely contributes to tree mortality.

Pathogenesis and Inhibition of Flaviviruses from a Carbohydrate Perspective

Directory of Open Access Journals (Sweden)

So Young Kim

2017-05-01

Full Text Available Flaviviruses are enveloped, positive single stranded ribonucleic acid (RNA viruses with various routes of transmission. While the type and severity of symptoms caused by pathogenic flaviviruses vary from hemorrhagic fever to fetal abnormalities, their general mechanism of host cell entry is similar. All pathogenic flaviviruses, such as dengue virus, yellow fever virus, West Nile virus, Japanese encephalitis virus, and Zika virus, bind to glycosaminglycans (GAGs through the putative GAG binding sites within their envelope proteins to gain access to the surface of host cells. GAGs are long, linear, anionic polysaccharides with a repeating disaccharide unit and are involved in many biological processes, such as cellular signaling, cell adhesion, and pathogenesis. Flavivirus envelope proteins are N-glycosylated surface proteins, which interact with C-type lectins, dendritic cell-specific intercellular adhesion molecule-3-grabbing non-integrin (DC-SIGN through their glycans. In this review, we discuss both host and viral surface receptors that have the carbohydrate components, focusing on the surface interactions in the early stage of flavivirus entry. GAG-flavivirus envelope protein interactions as well as interactions between flavivirus envelope proteins and DC-SIGN are discussed in detail. This review also examines natural and synthetic inhibitors of flaviviruses that are carbohydrate-based or carbohydrate-targeting. Both advantages and drawbacks of these inhibitors are explored, as are potential strategies to improve their efficacy to ultimately help eradicate flavivirus infections.

CARBOHYDRATE INTAKE CONSIDERATIONS FOR YOUNG ATHLETES

Directory of Open Access Journals (Sweden)

Veronica Montfort-Steiger

2007-09-01

Full Text Available Good nutritional practices are important for exercise performance and health during all ages. Athletes and especially growing children engaged in heavy training have higher energy and nutrient requirements compared to their non-active counterparts. Scientific understanding of sports nutrition for the young athlete is lacking behind the growing number of young athletes engaged in sports. Most of the sports nutrition recommendations given to athletic children and adolescents are based on adult findings due to the deficiency in age specific information in young athletes. Therefore, this review reflects on child specific sports nutrition, particularly on carbohydrate intake and metabolism that distinguishes the child athlete from the adult athlete. Children are characterised to be in an insulin resistance stage during certain periods of maturation, have different glycolytic/metabolic responses during exercise, have a tendency for higher fat oxidation during exercise and show different heat dissipation mechanisms compared to adults. These features point out that young athletes may need different nutritional advice on carbohydrate for exercise to those from adult athletes. Sport drinks for example may need to be adapted to children specific needs. However, more research in this area is warranted to clarify sports nutrition needs of the young athlete to provide better and healthy nutritional guidance to young athletes

Martini Coarse-Grained Force Field : Extension to Carbohydrates

NARCIS (Netherlands)

Lopez, Cesar A.; Rzepiela, Andrzej J.; de Vries, Alex H.; Dijkhuizen, Lubbert; Huenenberger, Philippe H.; Marrink, Siewert J.

2009-01-01

We present an extension of the Martini coarse-grained force field to carbohydrates. The parametrization follows the same philosophy as was used previously for lipids and proteins, focusing on the reproduction of partitioning free energies of small compounds between polar and nonpolar phases. The

Expression of an expansin carbohydrate-binding module affects ...

African Journals Online (AJOL)

Expansins are believed to be involved in disrupting the non-covalent adhesion of cellulose to matrix polysaccharides, thereby promoting wall creep. We have targeted a putative potato expansin (EXPA) carbohydrate-binding module (CBM) to the cell walls of tobacco plants. Histological examinations and electron ...

Self-powered wireless carbohydrate/oxygen sensitive biodevice based on radio signal transmission.

Science.gov (United States)

Falk, Magnus; Alcalde, Miguel; Bartlett, Philip N; De Lacey, Antonio L; Gorton, Lo; Gutierrez-Sanchez, Cristina; Haddad, Raoudha; Kilburn, Jeremy; Leech, Dónal; Ludwig, Roland; Magner, Edmond; Mate, Diana M; Conghaile, Peter Ó; Ortiz, Roberto; Pita, Marcos; Pöller, Sascha; Ruzgas, Tautgirdas; Salaj-Kosla, Urszula; Schuhmann, Wolfgang; Sebelius, Fredrik; Shao, Minling; Stoica, Leonard; Sygmund, Cristoph; Tilly, Jonas; Toscano, Miguel D; Vivekananthan, Jeevanthi; Wright, Emma; Shleev, Sergey

2014-01-01

Here for the first time, we detail self-contained (wireless and self-powered) biodevices with wireless signal transmission. Specifically, we demonstrate the operation of self-sustained carbohydrate and oxygen sensitive biodevices, consisting of a wireless electronic unit, radio transmitter and separate sensing bioelectrodes, supplied with electrical energy from a combined multi-enzyme fuel cell generating sufficient current at required voltage to power the electronics. A carbohydrate/oxygen enzymatic fuel cell was assembled by comparing the performance of a range of different bioelectrodes followed by selection of the most suitable, stable combination. Carbohydrates (viz. lactose for the demonstration) and oxygen were also chosen as bioanalytes, being important biomarkers, to demonstrate the operation of the self-contained biosensing device, employing enzyme-modified bioelectrodes to enable the actual sensing. A wireless electronic unit, consisting of a micropotentiostat, an energy harvesting module (voltage amplifier together with a capacitor), and a radio microchip, were designed to enable the biofuel cell to be used as a power supply for managing the sensing devices and for wireless data transmission. The electronic system used required current and voltages greater than 44 µA and 0.57 V, respectively to operate; which the biofuel cell was capable of providing, when placed in a carbohydrate and oxygen containing buffer. In addition, a USB based receiver and computer software were employed for proof-of concept tests of the developed biodevices. Operation of bench-top prototypes was demonstrated in buffers containing different concentrations of the analytes, showcasing that the variation in response of both carbohydrate and oxygen biosensors could be monitored wirelessly in real-time as analyte concentrations in buffers were changed, using only an enzymatic fuel cell as a power supply.

Postprandial lipid responses to standard carbohydrates used to determine glycaemic index values.

Science.gov (United States)

Vega-López, Sonia; Ausman, Lynne M; Matthan, Nirupa R; Lichtenstein, Alice H

2013-11-01

Prior studies assessing the metabolic effects of different types of carbohydrates have focused on their glycaemic response. However, the response of postprandial cardiometabolic risk indicators has not been considered in these studies. The present study assessed postprandial lipid responses to two forms of carbohydrates used as reference foods for glycaemic index determinations, white bread (50 g available carbohydrate) and glucose (50 g), under controlled conditions and with intra-individual replicate determinations. A total of twenty adults (20–70 years) underwent two cycles of challenges with each pair of reference foods (four challenges/person), administered in a random order on separate days under standard conditions. Serum lipids (total cholesterol, LDL-cholesterol, HDL-cholesterol, TAG and NEFA), glucose and insulin were monitored for 5 h post-ingestion. Oral glucose resulted in greater glycaemic and insulinaemic responses than white bread for the first 90 min and a greater subsequent decline after 120 min (P =0·0001). The initial decline in serum NEFA concentrations was greater after the oral glucose than after the white bread challenge, as was the rebound after 150 min (P = 0·001). Nevertheless, the type of carbohydrate had no significant effect on postprandial total cholesterol, LDL-cholesterol and HDL-cholesterol concentrations. Following an initial modest rise in TAG concentrations in response to both challenges, the values dropped below the fasting values for oral glucose but not for the white bread challenge. These data suggest that the type of carbohydrate used to determine the glycaemic index, bread or glucose, has little or modest effects on postprandial plasma cholesterol concentrations. Differences in TAG and NEFA concentrations over the 5 h time period were modest, and their clinical relevance is unclear.

Self-powered wireless carbohydrate/oxygen sensitive biodevice based on radio signal transmission.

Directory of Open Access Journals (Sweden)

Magnus Falk

Full Text Available Here for the first time, we detail self-contained (wireless and self-powered biodevices with wireless signal transmission. Specifically, we demonstrate the operation of self-sustained carbohydrate and oxygen sensitive biodevices, consisting of a wireless electronic unit, radio transmitter and separate sensing bioelectrodes, supplied with electrical energy from a combined multi-enzyme fuel cell generating sufficient current at required voltage to power the electronics. A carbohydrate/oxygen enzymatic fuel cell was assembled by comparing the performance of a range of different bioelectrodes followed by selection of the most suitable, stable combination. Carbohydrates (viz. lactose for the demonstration and oxygen were also chosen as bioanalytes, being important biomarkers, to demonstrate the operation of the self-contained biosensing device, employing enzyme-modified bioelectrodes to enable the actual sensing. A wireless electronic unit, consisting of a micropotentiostat, an energy harvesting module (voltage amplifier together with a capacitor, and a radio microchip, were designed to enable the biofuel cell to be used as a power supply for managing the sensing devices and for wireless data transmission. The electronic system used required current and voltages greater than 44 µA and 0.57 V, respectively to operate; which the biofuel cell was capable of providing, when placed in a carbohydrate and oxygen containing buffer. In addition, a USB based receiver and computer software were employed for proof-of concept tests of the developed biodevices. Operation of bench-top prototypes was demonstrated in buffers containing different concentrations of the analytes, showcasing that the variation in response of both carbohydrate and oxygen biosensors could be monitored wirelessly in real-time as analyte concentrations in buffers were changed, using only an enzymatic fuel cell as a power supply.

Simple vs. Complex Carbohydrate Dietary Patterns and the Global Overweight and Obesity Pandemic

Directory of Open Access Journals (Sweden)

Fabrizio Ferretti

2017-10-01

Full Text Available Nowadays, obesity and being overweight are among the major global health concerns. Many, diet-related diseases impose high tangible and intangible costs, and threaten the sustainability of health-care systems worldwide. In this study, we model, at the macroeconomic level, the impact of energy intake from different types of carbohydrates on the population’s BMI (body mass index. We proceed in three steps. First, we develop a framework to analyse both the consumption choices between simple and complex carbohydrates and the effects of these choices on people health conditions. Second, we collect figures for 185 countries (over the period 2012–2014 regarding the shares of simple (sugar and sweetener and complex (cereal carbohydrates in each country’s total dietary energy supply. Third, we use regression techniques to: (1 estimate the impact of these shares on the country’s prevalence of obesity and being overweight; (2 compute for each country an indicator of dietary pattern based on the ratio between simple and complex carbohydrates, weighted by their estimated effects on the prevalence of obesity and being overweight; and (3 measure the elasticity of the prevalence of obesity and being overweight with respect to changes in both carbohydrate dietary pattern and income per capita. We find that unhealthy eating habits and the associated prevalence of excessive body fat accumulation tend to behave as a ‘normal good’ in low, medium- and high-HDI (Human Development Index countries, but as an ‘inferior good’ in very high-HDI countries.

The Effect of a Three-Week Adaptation to a Low Carbohydrate/High Fat Diet on Metabolism and Cognitive Performance

Science.gov (United States)

1990-04-11

similar to that seen in starvation (5,21), hypocaloric weight loss diets (4, 29) and carbohydrate deprivation (12, 27, 28). Our subjects exhibited a...E.A.H. Sims. Comparison of carbohydrate-containing and carbohydrate-restricted hypocaloric diets in the treatment of obesity. J Clin Invest. 68:399-404...D-A247 575 . THE EFFECT OF A THREE-WEEK ADAPTATION TO A LOW CARBOHYDRATE / HIGH FAT DIET ON METABOLISM AND COGNITIVE PERFORMANCE C. G. GRAY 0. G

PROCARB: A Database of Known and Modelled Carbohydrate-Binding Protein Structures with Sequence-Based Prediction Tools

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Adeel Malik

2010-01-01

Full Text Available Understanding of the three-dimensional structures of proteins that interact with carbohydrates covalently (glycoproteins as well as noncovalently (protein-carbohydrate complexes is essential to many biological processes and plays a significant role in normal and disease-associated functions. It is important to have a central repository of knowledge available about these protein-carbohydrate complexes as well as preprocessed data of predicted structures. This can be significantly enhanced by tools de novo which can predict carbohydrate-binding sites for proteins in the absence of structure of experimentally known binding site. PROCARB is an open-access database comprising three independently working components, namely, (i Core PROCARB module, consisting of three-dimensional structures of protein-carbohydrate complexes taken from Protein Data Bank (PDB, (ii Homology Models module, consisting of manually developed three-dimensional models of N-linked and O-linked glycoproteins of unknown three-dimensional structure, and (iii CBS-Pred prediction module, consisting of web servers to predict carbohydrate-binding sites using single sequence or server-generated PSSM. Several precomputed structural and functional properties of complexes are also included in the database for quick analysis. In particular, information about function, secondary structure, solvent accessibility, hydrogen bonds and literature reference, and so forth, is included. In addition, each protein in the database is mapped to Uniprot, Pfam, PDB, and so forth.

CARBOHYDRATES OF CHANGES DURING THE FOLLICULAR DEVELOPMENT IN THE OVARY OF THE MOUSE DEER, TRAGULUS JAVANICUS

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Hamny -

2008-03-01

Full Text Available The data available on the female reproductive organ of mouse deer (Tragulus javanicus is still very limited. A study was therefore conducted to investigate the distribution and the concentration of carbohydrate residues during the development of ovary follicles. An ovary at luteal phase was used in this study. Thin sections of the ovary were prepared occording to the standard methods and they were then histochemically stained with flourecnece-labelled lectins such as peanut agglutinin (PNA, Ricinus communis agglutinin (RCA, Concanavalin A (Con A, Winged bean agglutinin (WGA and Ulex europaeus agglutinin (UEA. The result showed that changes in the distribution and the concentration of carbohydrate occured during the development of the follicle. During the preantral stage, the cytoplasm of oosit contained carbohydrate with the residues of glucosa dan mannosa. Zona pelusida contained carbohydrates with residues of glucosa, mannosa, galactosa dan N-asetylgalactosamine, whereas extracellular matrix contained carbohydrate with the residues of glucosa dan mannosa. In the antral follicle, the cyitoplasm of oocytes contained carbohydarte with the residues of galactosa dan N-asetylgalactosamine, whereas its zona pelusida, extracellular matrix and follicular fluid contained carbohydarte with the residues of fucosa, N-asetylglucosamin and cyalic acid. Diffrences in the types and the distribution pattern of carbohydrates were observed in this study, both in preantral and antral follicles.

Dietary carbohydrate source influences molecular fingerprints of the rat faecal microbiota

DEFF Research Database (Denmark)

Licht, Tine Rask; Hansen, Max; Poulsen, Morten

2006-01-01

Background: A study was designed to elucidate effects of selected carbohydrates on composition and activity of the intestinal microbiota. Five groups of eight rats were fed a western type diet containing cornstarch (reference group), sucrose, potato starch, inulin (a long-chained fructan) or olig......Background: A study was designed to elucidate effects of selected carbohydrates on composition and activity of the intestinal microbiota. Five groups of eight rats were fed a western type diet containing cornstarch (reference group), sucrose, potato starch, inulin (a long-chained fructan...... of coliform bacteria in faeces. In the inulin and oligofructose groups, higher levels of butyrate and propionate, respectively, were measured. Principal Component Analysis of profiles of the faecal microbiota obtained by Denaturing Gradient Gel Electrophoresis (DGGE) of PCR amplified bacterial 16S rRNA genes...... and are not expected to reach the large intestine, the DGGE band patterns obtained indicated that these carbohydrates indeed affected the composition of bacteria in the large gut. Also the two fructans resulted in completely different molecular fingerprints of the faecal microbiota, indicating that even though...

Aerobic Exercise Training Adaptations Are Increased by Postexercise Carbohydrate-Protein Supplementation

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Lisa Ferguson-Stegall

2011-01-01

Full Text Available Carbohydrate-protein supplementation has been found to increase the rate of training adaptation when provided postresistance exercise. The present study compared the effects of a carbohydrate and protein supplement in the form of chocolate milk (CM, isocaloric carbohydrate (CHO, and placebo on training adaptations occurring over 4.5 weeks of aerobic exercise training. Thirty-two untrained subjects cycled 60 min/d, 5 d/wk for 4.5 wks at 75–80% of maximal oxygen consumption (VO2 max. Supplements were ingested immediately and 1 h after each exercise session. VO2 max and body composition were assessed before the start and end of training. VO2 max improvements were significantly greater in CM than CHO and placebo. Greater improvements in body composition, represented by a calculated lean and fat mass differential for whole body and trunk, were found in the CM group compared to CHO. We conclude supplementing with CM postexercise improves aerobic power and body composition more effectively than CHO alone.

Hearing Loss, Dizziness, and Carbohydrate Metabolism

OpenAIRE

Albernaz, Pedro L. Mangabeira

2015-01-01

Abstract Introduction Metabolic activity of the inner ear is very intense, and makes it sensitive to changes in the body homeostasis. This study involves a group of patients with inner ear disorders related to carbohydrate metabolism disturbances, including hearing loss, tinnitus, dizziness, and episodes of vertigo. Objectives To describe the symptoms of metabolic inner ear disorders and the examinations required to establish diagnoses. These symptoms are often the first to allow for an e...

A qualitative investigation of patients' understanding of carbohydrate in the clinical management of type 2 diabetes.

Science.gov (United States)

Breen, C; McKenzie, K; Yoder, R; Ryan, M; Gibney, M J; O'Shea, D

2016-04-01

A healthy diet is the cornerstone of type 2 diabetes (T2DM) self-management. Carbohydrate is of particular interest as the nutrient with the greatest direct effect on blood glucose (BG) levels. The present study aimed to explore T2DM patients' understanding of carbohydrate and beliefs around the role of carbohydrate in T2DM management. Fifteen semi-structured interviews were conducted with T2DM patients. Interviews were audio-recorded and transcribed, and a deductive thematic approach to analysis was employed using the Framework method. Four significant themes emerged: (i) a naïve conceptual understanding of carbohydrate and sugar-centric specificity to dietary behaviours; (ii) a narrow focus on BG management to the neglect of overall dietary balance; (iii) positive reception of moderate dietary advice focused on portion control from healthcare professionals (HCPs); and (iv) the impact of external moderators of dietary choices, including the influence of significant others, emotional and opportunistic eating and budgetary constraints. Participants' beliefs and understanding of carbohydrate led to an overemphasis on sugar restriction for blood glucose control to the neglect of their overall dietary balance. Diabetes educators need to place greater emphasis on the role of various types of carbohydrate foods for glycaemic control, as well as on concepts of wider metabolic health, during T2DM dietary education. Participants placed a high level of trust and value on practical, moderate portion control advice from HCPs regarding carbohydrate foods. However, HCPs need to be cognisant of external moderators of behaviour, such as the influence of family and friends, budgetary constraints and environmental eating triggers. © 2015 The British Dietetic Association Ltd.

Fueling the caries process: carbohydrate metabolism and gene regulation by Streptococcus mutans

Science.gov (United States)

Moye, Zachary D.; Zeng, Lin; Burne, Robert A.

2014-01-01

The nature of the oral cavity and host behaviors has mandated that the oral microbiota evolve mechanisms for coping with environmental fluctuations, especially changes in the type and availability of carbohydrates. In the case of human dental caries, the presence of excess carbohydrates is often responsible for altering the local environment to be more favorable for species associated with the initiation and progression of disease, including Streptococcus mutans. Some of the earliest endeavors to understand how cariogenic species respond to environmental perturbations were carried out using chemostat cultivation, which provides fine control over culture conditions and bacterial behaviors. The development of genome-scale methodologies has allowed for the combination of sophisticated cultivation technologies with genome-level analysis to more thoroughly probe how bacterial pathogens respond to environmental stimuli. Recent investigations in S. mutans and other closely related streptococci have begun to reveal that carbohydrate metabolism can drastically impact pathogenic potential and highlight the important influence that nutrient acquisition has on the success of pathogens; inside and outside of the oral cavity. Collectively, research into pathogenic streptococci, which have evolved in close association with the human host, has begun to unveil the essential nature of careful orchestration of carbohydrate acquisition and catabolism to allow the organisms to persist and, when conditions allow, initiate or worsen disease. PMID:25317251

Fueling the caries process: carbohydrate metabolism and gene regulation by Streptococcus mutans

Directory of Open Access Journals (Sweden)

Zachary D. Moye

2014-09-01

Full Text Available The nature of the oral cavity and host behaviors has mandated that the oral microbiota evolve mechanisms for coping with environmental fluctuations, especially changes in the type and availability of carbohydrates. In the case of human dental caries, the presence of excess carbohydrates is often responsible for altering the local environment to be more favorable for species associated with the initiation and progression of disease, including Streptococcus mutans. Some of the earliest endeavors to understand how cariogenic species respond to environmental perturbations were carried out using chemostat cultivation, which provides fine control over culture conditions and bacterial behaviors. The development of genome-scale methodologies has allowed for the combination of sophisticated cultivation technologies with genome-level analysis to more thoroughly probe how bacterial pathogens respond to environmental stimuli. Recent investigations in S. mutans and other closely related streptococci have begun to reveal that carbohydrate metabolism can drastically impact pathogenic potential and highlight the important influence that nutrient acquisition has on the success of pathogens; inside and outside of the oral cavity. Collectively, research into pathogenic streptococci, which have evolved in close association with the human host, has begun to unveil the essential nature of careful orchestration of carbohydrate acquisition and catabolism to allow the organisms to persist and, when conditions allow, initiate or worsen disease.

Behavioural responses of the snail Lymnaea acuminata to carbohydrates in snail-attractant pellets

Science.gov (United States)

Tiwari, Farindra; Singh, D. K.

Snail control is one of the most important tools in the campaign to reduce the incidence of fascioliasis. In order to attain this objective, the method of bait formulation in order to contain an attractant and a molluscicide is an expedient approach to lure the target snail population to the molluscicide. This study identifies certain carbohydrates, namely sucrose, maltose, glucose, fructose and starch, for preparing such baits. These were tested on Lymnaea acuminata, an intermediate host of the digenean trematodes Fasciola hepatica and Fasciola gigantica. The behavioural responses of snails to these carbohydrates were examined. Significant variations in behavioural responses were observed in the snail even when the five carbohydrates were used in low concentrations in snail-attractant pellets. Starch emerged as the strongest attractant for Lymnaea acuminata, followed by maltose.

Catalytic Conversion of Carbohydrates to Furanic Derivatives in the Presence of Choline Chloride

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François Jérôme

2017-07-01

Full Text Available The synthesis of furanic derivatives (5-hydroxymethylfurfural (HMF, furfural… from carbohydrates is of high interest for a wide range of applications. These reactions are carried out in the presence of various solvents, and among them choline chloride can be used. It is a salt that can form a low melting mixture with a carbohydrate (fructose, glucose… or a deep eutectic mixture with carboxylic acid. A review of the studies performed in the conversion of carbohydrates to furanic derivatives in the presence of choline chloride is presented here with the advantages and drawbacks of this solvent. Choline chloride can enhance the selectivity to HMF by stabilizing effect and allows the conversion of highly concentrated feed. However, the extraction of the products from these solvents still needs improvement.

Sublethal effects of manganese on the carbohydrate metabolism of ...

African Journals Online (AJOL)

Carbohydrate metabolism provides (1) energy,. (2) precursors for synthetic reactions ... as a response to the adrenal corticotrophic hormone (ACTH) from the ... During the exposure experiments, control groups were also set-up. The control fish ...

Post-exercise ingestion of a carbohydrate and casein hydrolysate ...

African Journals Online (AJOL)

an isocaloric carbohydrate and protein supplement and ingested the assigned ..... week, and day showed that the 4-way interaction with “condition” ..... on markers of muscle recovery following soccer training: a randomized cross-over study.

Comparison of a carbohydrate-free diet vs. fasting on plasma glucose, insulin and glucagon in type 2 diabetes.

Science.gov (United States)

Nuttall, Frank Q; Almokayyad, Rami M; Gannon, Mary C

2015-02-01

Hyperglycemia improves when patients with type 2 diabetes are placed on a weight-loss diet. Improvement typically occurs soon after diet implementation. This rapid response could result from low fuel supply (calories), lower carbohydrate content of the weight-loss diet, and/or weight loss per se. To differentiate these effects, glucose, insulin, C-peptide and glucagon were determined during the last 24 h of a 3-day period without food (severe calorie restriction) and a calorie-sufficient, carbohydrate-free diet. Seven subjects with untreated type 2 diabetes were studied. A randomized-crossover design with a 4-week washout period between arms was used. Results from both the calorie-sufficient, carbohydrate-free diet and the 3-day fast were compared with the initial standard diet consisting of 55% carbohydrate, 15% protein and 30% fat. The overnight fasting glucose concentration decreased from 196 (standard diet) to 160 (carbohydrate-free diet) to 127 mg/dl (fasting). The 24 h glucose and insulin area responses decreased by 35% and 48% on day 3 of the carbohydrate-free diet, and by 49% and 69% after fasting. Overnight basal insulin and glucagon remained unchanged. Short-term fasting dramatically lowered overnight fasting and 24 h integrated glucose concentrations. Carbohydrate restriction per se could account for 71% of the reduction. Insulin could not entirely explain the glucose responses. In the absence of carbohydrate, the net insulin response was 28% of the standard diet. Glucagon did not contribute to the metabolic adaptations observed. Published by Elsevier Inc.

Lyoluminescence of irradiated carbohydrates - the role of dissolution rate and oxygen

International Nuclear Information System (INIS)

Baugh, P.J.; Laflin, P.

1980-01-01

The lyoluminescent emission from γ-irradiated carbohydrates is shown to be strictly controlled by the rate of dissolution of the solid and the availability of oxygen for reaction during dissolution. These effects are explained in terms of oxidation of trapped radicals diffusing from the dissolving carbohydrate which react in an 'active volume' set up at the onset of dissolution at the crystal-water interface. At irradiation doses greater than 82.5 krad for mannose there is a suppression of the emission which results from an incomplete oxidation of the diffusing radicals due to insufficient O 2 in the active volume leading to a reaction involving unoxidised radicals and peroxyl radicals which are believed to be the precursors of the emission. This reaction is suppressed when the oxygen supply to the 'active volume' is increased. This can be achieved by increasing the oxygen content of the injector gas and indirectly by decreasing the solubility of the carbohydrate. Under these conditions the linear dose range of the lyoluminescence response is extended to ca. 330 krad close to the dose at which trapped radicals saturate in the irradiated solid carbohydrate. Although lyoluminescence is a liquid surface-layer effect as expected the generation of the emission is greatly influenced by oxygen present in the injection atmosphere. Quenching of lyoluminescence by adding peroxyl radical quenchers Cu(II) ions and hydroquinone, suggests that the reaction involving these quenchers also occurs in the 'active volume'. The results generally can be interpreted in terms of a diffusion model. (author)

Influence of radioprotectors of various chemical compounds on the dynamic performance capacity and carbohydrate metabolism

International Nuclear Information System (INIS)

Vladimirov, V.G.; Golubentsev, D.A.; Merkina, T.N.; Smirnova, S.M.

1978-01-01

Studied is the effect of the most effective radiotectors (gammaphos, cystamine and mexamine) on some factors of carbohydrate metabolism and working capacity of rats. In the effect of preparations studied great differences are established. Decrease of glycogen storage in liver and museles increase of lactate and pyruate level in blood as compared to control, decrease of animal working capacity are observed at introducing cystamine into rats when in rest and while dosed muscular loadings. Mexamine causes great shifts in carbohydrate exchange (in combination with physical loadings), and decreases animal strength. Gammaphos does not influence carbohydrate metabolism and does not decrease animal working capacity

Quantitative NMR Approach to Optimize the Formation of Chemical Building Blocks from Abundant Carbohydrates.

Science.gov (United States)

Elliot, Samuel G; Tolborg, Søren; Sádaba, Irantzu; Taarning, Esben; Meier, Sebastian

2017-07-21

The future role of biomass-derived chemicals relies on the formation of diverse functional monomers in high yields from carbohydrates. Recently, it has become clear that a series of α-hydroxy acids, esters, and lactones can be formed from carbohydrates in alcohol and water solvents using tin-containing catalysts such as Sn-Beta. These compounds are potential building blocks for polyesters bearing additional olefin and alcohol functionalities. An NMR approach was used to identify, quantify, and optimize the formation of these building blocks in the Sn-Beta-catalyzed transformation of abundant carbohydrates. Record yields of the target molecules can be achieved by obstructing competing reactions through solvent selection. © 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

Expanded metabolomics approach to profiling endogenous carbohydrates in the serum of ovarian cancer patients.

Science.gov (United States)

Cheng, Yu; Li, Li; Zhu, Bangjie; Liu, Feng; Wang, Yan; Gu, Xue; Yan, Chao

2016-01-01

We applied hydrophilic interaction liquid chromatography coupled with tandem mass spectrometry to the quantitative analysis of serum from 58 women, including ovarian cancer patients, ovarian benign tumor patients, and healthy controls. All of these ovarian cancer and ovarian benign tumor patients have elevated cancer antigen 125, which makes them clinically difficult to differentiate the malignant from the benign. All of the 16 endogenous carbohydrates were quantitatively detected in the human sera, of which, eight endogenous carbohydrates were significantly different (P-value carbohydrates in the expanded metabolomics approach after the global metabolic profiling are characterized and are potential biomarkers for the early diagnosis of ovarian cancer. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Reduced cerebral oxygen–carbohydrate index during endotracheal intubation in vascular surgical patients

DEFF Research Database (Denmark)

Fabricius-Bjerre, Andreas; Overgaard, Anders; Winther-Olesen, Marie

2015-01-01

Brain activation reduces balance between cerebral consumption of oxygen versus carbohydrate as expressed by the so-called cerebral oxygen-carbohydrate-index (OCI). We evaluated whether preparation for surgery, anaesthesia including tracheal intubation and surgery affect OCI. In patients undergoing...... aortic surgery, arterial to internal jugular venous (a-v) concentration differences for oxygen versus lactate and glucose were determined from before anaesthesia to when the patient left the recovery room. Intravenous anaesthesia was supplemented with thoracic epidural anaesthesia for open aortic surgery...

Acceptability of Carbohydrate Gels During a 5-Day US Marine Corps Basic Officer Course Field Exercise

National Research Council Canada - National Science Library

Tharion, William

2001-01-01

...). Low carbohydrate availability negatively affects physical performance (8,10). Soldiers may experience unnecessary loss of muscle mass and other problems due to inadequate carbohydrate intake when exercising vigorously (<300 g/d) (4,6,8,9,11...

Fad diets and obesity--Part IV: Low-carbohydrate vs. low-fat diets.

Science.gov (United States)

Moyad, Mark A

2005-02-01

The first three parts of this series of articles covered the basics of some of the more popular low-carbohydrate diets, and the theories behind them. In the fourth and final part of this series, some of the more popular low-fat and low-calorie diets, such as the Ornish diet and Weight Watchers, are covered briefly. Recently, several clinical trials of longer duration that compared low-carbohydrate versus low-fat diets have been published. These studies demonstrate that some of the low-carbohydrate diets result in reduced weight in the short-term, but their ability to reduce weight long-term any better than low-fat or other diets has been questioned. Most popular or fad diets have some positive messages contained within them and some preliminary positive short-term results, but overall the compliance rates with any fad diet are very poor over the long-term. The decision to go on any diet should be made with a health professional who can monitor the patient closely.

Functional properties of nisin–carbohydrate conjugates formed by radiation induced Maillard reaction

International Nuclear Information System (INIS)

Muppalla, Shobita R.; Sonavale, Rahul; Chawla, Surinder P.; Sharma, Arun

2012-01-01

Nisin–carbohydrate conjugates were prepared by irradiating nisin either with glucose or dextran. Increase in browning and formation of intermediate products was observed with a concomitant decrease in free amino and reducing sugar groups indicating occurrence of the Maillard reaction catalyzed by irradiation. Nisin–carbohydrate conjugates showed a broad spectrum antibacterial activity against Gram negative bacteria (Escherichia coli, Pseudomonas fluorescence) as well as Gram positive bacteria (Staphylococcus aureus, Bacillus cereus). Results of antioxidant assays, including that of DPPH radical-scavenging activity and reducing power, showed that the nisin–dextran conjugates possessed better antioxidant potential than nisin–glucose conjugate. These results suggested that it was possible to enhance the functional properties of nisin by preparing radiation induced conjugates suitable for application in food industry. - Highlights: ► Nisin–carbohydrate conjugates were prepared using radiation induced Maillard reaction. ► Conjugation of nisin with dextran/glucose resulted in improvement of antibacterial spectrum. ► Conjugates of nisin with dextran/glucose had significant radical scavenging activity.

Verification of protein sparing by feeding carbohydrate to common carp Cyprinus carpio

Science.gov (United States)

Cheng, Zhenyan; Li, Jinghui; Zhang, Baolong; Fang, Zhenzhen; Sun, Jinhui; Bai, Dongqing; Sun, Jinsheng; Qiao, Xiuting

2017-03-01

A 9-week feeding trial in floating freshwater cages (1.0 m×1.0 m×2.0 m) was conducted to study the effects of different dietary levels of protein and starch on growth, body composition, and gene expression of enzymes in common carp, Cyprinus carpio (mean body weight, 36.12±1.18 g) to evaluate the protein-sparing effect of dietary carbohydrate. Four diets were formulated with corn starch as the carbohydrate source to obtain corn starch levels of 6.5%, 13%, 19.5%, or 26% and protein levels of 30.5%, 28.2%, 26.4%, and 24.2%. The results showed no differences in growth performance of fish fed the diets with different protein and corn starch levels, but body composition and glucose metabolic enzyme activity of carp were significantly affected by the different diets ( P 0.05). In summary, the results indicate a protein-sparing effect by substituting carbohydrate in the diet of common carp.

Dietary ratio of protein to carbohydrate induces plastic responses in the gastrointestinal tract of mice

DEFF Research Database (Denmark)

Sørensen, Allan; Mayntz, David; Simpson, Stephen James

2010-01-01

of the protein-rich food. In contrast, intestines, caeca and colons were heavier when diets contained more carbohydrates and less protein. This response may function to increase the digestive rate of carbohydrates when the dietary content of this macronutrient increases, but it may also indicate a compensatory...

Quantum dots assisted laser desorption/ionization mass spectrometric detection of carbohydrates: qualitative and quantitative analysis.

Science.gov (United States)

Bibi, Aisha; Ju, Huangxian

2016-04-01

A quantum dots (QDs) assisted laser desorption/ionization mass spectrometric (QDA-LDI-MS) strategy was proposed for qualitative and quantitative analysis of a series of carbohydrates. The adsorption of carbohydrates on the modified surface of different QDs as the matrices depended mainly on the formation of hydrogen bonding, which led to higher MS intensity than those with conventional organic matrix. The effects of QDs concentration and sample preparation method were explored for improving the selective ionization process and the detection sensitivity. The proposed approach offered a new dimension to the application of QDs as matrices for MALDI-MS research of carbohydrates. It could be used for quantitative measurement of glucose concentration in human serum with good performance. The QDs served as a matrix showed the advantages of low background, higher sensitivity, convenient sample preparation and excellent stability under vacuum. The QDs assisted LDI-MS approach has promising application to the analysis of carbohydrates in complex biological samples. Copyright © 2016 John Wiley & Sons, Ltd.

Circulating FGF21 in humans is potently induced by short term overfeeding of carbohydrates

Directory of Open Access Journals (Sweden)

Anne-Marie Lundsgaard

2017-01-01

Full Text Available Objective: Fibroblast-growth factor 21 (FGF21 is thought to be important in metabolic regulation. Recently, low protein diets have been shown to increase circulating FGF21 levels. However, when energy contribution from dietary protein is lowered, other macronutrients, such as carbohydrates, must be increased to meet eucaloric balance. This raises the possibility that intake of a diet rich in carbohydrates may induce an increase in plasma FGF21 levels per se. Here we studied the role of dietary carbohydrates on the levels of circulating FGF21 and concomitant physiologic effects by feeding healthy men a carbohydrate rich diet without reducing protein intake. Methods: A diet enriched in carbohydrates (80 E% carbohydrate; CHO and a eucaloric control diet (CON were provided to nine healthy men for three days. The energy intake during the CHO diet was increased (+75% energy to ensure similar dietary protein intake in CHO and CON. To control for the effect of caloric surplus, we similarly overfed (+75% energy the same subjects for three days with a fat-rich diet (78 E% fat; FAT, consisting of primarily unsaturated fatty acids. The three diets were provided in random order. Results: After CHO, plasma FGF21 concentration increased 8-fold compared to CON (329 ± 99 vs. 39 ± 9 pg ml−1, p < 0.05. In contrast, after FAT only a non-significant tendency (p = 0.073 to an increase in plasma FGF21 concentration was found. The increase in FGF21 concentration after CHO correlated closely (r = 0.88, p < 0.01 with increased leg glucose uptake (62%, p < 0.05 and increased hepatic glucose production (17%, p < 0.01, indicating increased glucose turnover. Plasma fatty acid (FA concentration was decreased by 68% (p < 0.01, supported by reduced subcutaneous adipose tissue HSL Ser660 phosphorylation (p < 0.01 and perilipin 1 protein content (p < 0.01, pointing to a suppression of adipose tissue lipolysis. Concomitantly, a 146% increase in the

Effect of a low-carbohydrate diet on respiratory quotient of infants with chronic lung disease.

Science.gov (United States)

Suteerojntrakool, Orapa; Sanguanrungsirikul, Sompol; Sritippayawan, Suchada; Jantarabenjakul, Watsamon; Sirimongkol, Pathama; Chomtho, Sirinuch

2015-01-01

To compare the respiratory quotient in infants with chronic lung disease before and after receiving a modular diet with slightly lower carbohydrate content. Infants with chronic lung disease from the King Chulalongkorn Memorial Hospital were enrolled and assessed for nutritional status, severity of chronic lung disease and dietary intake. Indirect calorimetry was performed using a custom-made airtight canopy with O2 and CO2 sensors. Respiratory quotient (RQ) was calculated from VCO2/VO2 during the period they were fed low carbohydrates (37% of total calories) for at least 24 hours vs. a standard diet (47% carbohydrate). These two formulas were similar in terms of caloric density and protein content. Each patient received at least 100-150 kcal/ kg/day during the study period. Respiratory quotients of the same patient receiving the two diets were compared by using Wilcoxon signed-rank test. A total of 14 patients (median age 7 months, range 1-26 months) were recruited. Twelve children had weight for age Z-score below-2SD. Their median weight for age Z-score, length for age Z-score and weight for length Z-score were -2.89, -3.08 and -1.24, respectively. The median RQ measured during the low carbohydrate diet was 0.96 (interquartile range 0.95-0.97), significantly lower than the median RQ during the standard diet, which was 1.04 (0.97-1.10). However, the respiratory rate revealed no significant difference. Two participants with underlying gastroesophageal reflux disease showed higher RQ after low carbohydrate formula feeding, which might be a result of hypersecretion due to its high fat content. Diet with slightly lower carbohydrate content can reduce the RQ in infants with chronic lung disease compared to the standard enteral formula. A 10-percent reduction of carbohydrate content may provide a sizeable effect in this group of patients. Nevertheless, the clinical significance of this finding requires further investigation.

Complex carbohydrate utilization by the healthy human microbiome.

Directory of Open Access Journals (Sweden)

Brandi L Cantarel

Full Text Available The various ecological habitats in the human body provide microbes a wide array of nutrient sources and survival challenges. Advances in technology such as DNA sequencing have allowed a deeper perspective into the molecular function of the human microbiota than has been achievable in the past. Here we aimed to examine the enzymes that cleave complex carbohydrates (CAZymes in the human microbiome in order to determine (i whether the CAZyme profiles of bacterial genomes are more similar within body sites or bacterial families and (ii the sugar degradation and utilization capabilities of microbial communities inhabiting various human habitats. Upon examination of 493 bacterial references genomes from 12 human habitats, we found that sugar degradation capabilities of taxa are more similar to others in the same bacterial family than to those inhabiting the same habitat. Yet, the analysis of 520 metagenomic samples from five major body sites show that even when the community composition varies the CAZyme profiles are very similar within a body site, suggesting that the observed functional profile and microbial habitation have adapted to the local carbohydrate composition. When broad sugar utilization was compared within the five major body sites, the gastrointestinal track contained the highest potential for total sugar degradation, while dextran and peptidoglycan degradation were highest in oral and vaginal sites respectively. Our analysis suggests that the carbohydrate composition of each body site has a profound influence and probably constitutes one of the major driving forces that shapes the community composition and therefore the CAZyme profile of the local microbial communities, which in turn reflects the microbiome fitness to a body site.

Carbohydrate protease conjugates: Stabilized proteases for peptide synthesis

Energy Technology Data Exchange (ETDEWEB)

Wartchow, C.A.; Wang, Peng; Bednarski, M.D.; Callstrom, M.R. [Ohio State Univ., Columbus, OH (United States)]|[Lawrence Berkeley Lab., CA (United States)

1995-12-31

The synthesis of oligopeptides using stable carbohydrate protease conjugates (CPCs) was examined in acetonitrile solvent systems. CPC[{alpha}-chymotrypsin] was used for the preparation of peptides containing histidine, phenylalanine, tryptophan in the P{sub 1} position in 60-93% yield. The CPC[{alpha}-chymotrypsin]-catalyzed synthesis of octamer Z-Gly-Gly-Phe-Gly-Gly-Phe-Gly-Gly-OEt from Z-Gly-Gly-Phe-Gly-Gly-Phe-OMe was achieved in 71% yield demonstrating that synthesis peptides containing both hydrophylic and hydrophobic amino acids. The P{sub 2} specificity of papain for aromatic residues was utilized for the 2 + 3 coupling of Z-Tyr-Gly-OMe to H{sub 2}N-Gly-Phe-Leu-OH to generate the leucine enkephalin derivative in 79% yield. Although papain is nonspecific for the hydrolysis of N-benzyloxycarbonyl amino acid methyl esters in aqueous solution, the rates of synthesis for these derivitives with nucleophile leucine tert-butyl ester differed by nearly 2 orders of magnitude. CPC[thermolysin] was used to prepare the aspartame precursor Z-Asp-Phe-OMe in 90% yield. The increased stability of CPCs prepared from periodate-modified poly(2-methacryl- amido-2-deoxy-D-glucose), poly(2-methacrylamido-2-deoxy-D-galactose), and poly(5-methacryl-amido-5-deoxy-D-ribose), carbohydrate materials designed to increase the aldehyde concentration in aqueous solution, suggests that the stability of CPCs is directly related to the aldehyde concentration of the carbohydrate material. Periodate oxidation of poly(2-methacrylamido-2-deoxy-D-glucose) followed by covalent attachment to {alpha}-chymotrypsin gave a CPC with catalytic activity in potassium phosphate buffer at 90{degrees}C for 2 h. 1 fig., 1 tab., 40 refs.

Does oral carbohydrate supplementation improve labour outcome? A systematic review and individual patient data meta-analysis.

Science.gov (United States)

Malin, G L; Bugg, G J; Thornton, J; Taylor, M A; Grauwen, N; Devlieger, R; Kardel, K R; Kubli, M; Tranmer, J E; Jones, N W

2016-03-01

Labour is a period of significant physical activity. The importance of carbohydrate intake to improve outcome has been recognised in sports medicine and general surgery. To assess the effect of oral carbohydrate supplementation on labour outcomes. MEDLINE (1966-2014), Embase, the Cochrane Library and clinical trial registries. Randomised controlled trials (RCT) of women randomised to receive oral carbohydrate in labour (inclusion criteria. Six authors responded, four supplied data (n = 691). Three studies used isotonic drinks (one placebo-controlled, two compared with standard care), and one an advice booklet regarding carbohydrate intake. The mean difference in energy intake between the intervention and control groups was small [three studies, 195 kilocalories (kcal), 95% CI 118-273]. There was no difference in the risk of caesarean section (RR 1.15, 95% CI 0.83- 1.61), instrumental birth (RR 1.26, 95% CI 0.96-1.66) or syntocinon augmentation (RR 0.99, 95% CI 0.86-1.13). Length of labour was similar (mean difference -3.15 minutes, 95% CI -35.14 to 41.95). Restricting the analysis to primigravid women did not affect the result. Oral carbohydrates did not increase the risk of vomiting (RR 1.09, 95% CI 0.78-1.52) or 1-minute Apgar score labour outcome. Oral carbohydrate does not affect labour. But the difference between intervention and control equals 10 teaspoons sugar. © 2016 Royal College of Obstetricians and Gynaecologists.

EFSA Panel on Dietetic Products, Nutrition, and Allergies (NDA); Scientific Opinion on Dietary Reference Values for carbohydrates and dietary fibre

OpenAIRE

Tetens, Inge

2011-01-01

This Opinion of the EFSA Panel on Dietetic Products, Nutrition, and Allergies (NDA) deals with the establishment of Dietary Reference Values for carbohydrates and dietary fibre. Nutritionally, two broad categories of carbohydrates can be differentiated: “glycaemic carbohydrates”, i.e. carbohydrates digested and absorbed in the human small intestine, and „dietary fibre‟, non-digestible carbohydrates passing to the large intestine. In this Opinion, dietary fibre is defined as non-digestible car...

Distribution and seasonal variation of concentrations of particulate carbohydrates and uronic acids in the northern Indian Ocean

Digital Repository Service at National Institute of Oceanography (India)

Khodse, V.B.; Fernandes, L.; Gopalakrishna, V.V.; Bhosle, N.B.; Fernandes, V.; Matondkar, S.G.P.; Bhushan, R.

particulate carbohydrate (TPCHO), total particulate uronic acid (TPURA) and total particulate neutral carbohydrate (TPNCHO) concentrations and composition. Strong spatial, temporal and depth related variations were evident in the distribution...

Differential impact of amino acids on OXPHOS system activity following carbohydrate starvation in Arabidopsis cell suspensions.

Science.gov (United States)

Cavalcanti, João Henrique F; Quinhones, Carla G S; Schertl, Peter; Brito, Danielle S; Eubel, Holger; Hildebrandt, Tatjana; Nunes-Nesi, Adriano; Braun, Hans-Peter; Araújo, Wagner L

2017-12-01

Plant respiration mostly depends on the activity of glycolysis and the oxidation of organic acids in the tricarboxylic acid cycle to synthesize ATP. However, during stress situations plant cells also use amino acids as alternative substrates to donate electrons through the electron-transfer flavoprotein (ETF)/ETF:ubiquinone oxidoreductase (ETF/ETFQO) complex to the mitochondrial electron transport chain (mETC). Given this, we investigated changes of the oxidative phosphorylation (OXPHOS) system in Arabidopsis thaliana cell culture under carbohydrate starvation supplied with a range of amino acids. Induction of isovaleryl-CoA dehydrogenase (IVDH) activity was observed under carbohydrate starvation which was associated with increased amounts of IVDH protein detected by immunoblotting. Furthermore, activities of the protein complexes of the mETC were reduced under carbohydrate starvation. We also observed that OXPHOS system activity behavior is differently affected by different amino acids and that proteins associated with amino acids catabolism are upregulated in cells following carbohydrate starvation. Collectively, our results support the contention that ETF/ETFQO is an essential pathway to donate electrons to the mETC and that amino acids are alternative substrates to maintain respiration under carbohydrate starvation. © 2017 Scandinavian Plant Physiology Society.

The sweet world of liquid crystals : The synthesis of non-amphiphilic carbohydrate-derived liquid crystals

NARCIS (Netherlands)

Smits, E

1998-01-01

The research in carbohydrate-derived liquid crystals was initiated by a review article by Jeffrey in 1986. This is rather late if one considers that the research on liquid crystals underwent a revival already in the 1960s after the discovery of the liquid crystal display (LCD). Carbohydrates were

Carbohydrate- and protein-rich diets in McArdle disease: Effects on exercise capacity

DEFF Research Database (Denmark)

Andersen, S.T.; Vissing, J.

2008-01-01

metabolism during exercise, which questions the effect of protein in McArdle disease. METHODS: In a crossover, open design, we studied 7 patients with McArdle disease, who were randomised to follow either a carbohydrate- or protein-rich diet for three days before testing. Caloric intake on each diet...... was identical, and was adjusted to the subject's weight, age and sex. After each diet, exercise tolerance and maximal work capacity were tested on a bicycle ergometer, using a constant workload for 15 minutes followed by an incremental workload to exhaustion. RESULTS: During the constant workload, heart rate...... capacity and exercise tolerance to submaximal workloads by maintaining a diet high in carbohydrate instead of protein. The carbohydrate diet not only improves tolerance to every-day activities, but will likely also help to prevent exercise-induced episodes of muscle injury in McArdle disease Udgivelsesdato...

In-situ annotation of carbohydrate diversity, abundance, and degradability in highly complex mixtures using NMR spectroscopy

DEFF Research Database (Denmark)

Meier, Sebastian

2014-01-01

Many functions of carbohydrates depend on the detection of short structural motifs, approximately up to hexasaccharide length, by receptors or catalysts. This study investigates the usefulness of state-of-the-art 1H–13C nuclear-magnetic-resonance (NMR) spectroscopy for characterizing the diversity......, abundance, and degradability of such short structural motifs in plant-derived carbohydrates. Assignments of carbohydrate signals for 1H–13C NMR spectra of beer, wine, and fruit juice yield up to >130 assignments in situ, i.e. in individual samples without separation or derivatization. More than 500...... structural motifs can be resolved over a concentration range of ~103 in experiments of a few hours duration. The diversity of carbohydrate units increases according to power laws at lower concentrations for both cereal and fruit-derived samples. Simple graphs resolve the smaller overall contribution of more...

EFSA Panel on Dietetic Products, Nutrition, and Allergies (NDA); Scientific Opinion on Dietary Reference Values for carbohydrates and dietary fibre

DEFF Research Database (Denmark)

Tetens, Inge

This Opinion of the EFSA Panel on Dietetic Products, Nutrition, and Allergies (NDA) deals with the establishment of Dietary Reference Values for carbohydrates and dietary fibre. Nutritionally, two broad categories of carbohydrates can be differentiated: “glycaemic carbohydrates”, i.e. carbohydrates...

Natural Cytotoxicity Receptors: Pattern Recognition and Involvement of Carbohydrates

Directory of Open Access Journals (Sweden)

Angel Porgador

2005-01-01

Full Text Available Natural cytotoxicity receptors (NCRs, expressed by natural killer (NK cells, trigger NK lysis of tumor and virus-infected cells on interaction with cell-surface ligands of these target cells. We have determined that viral hemagglutinins expressed on the surface of virus-infected cells are involved in the recognition by the NCRs, NKp44 and NKp46. Recognition of tumor cells by the NCRs NKp30 and NKp46 involves heparan sulfate epitopes expressed on the tumor cell membrane. Our studies provide new evidence for the identity of the ligands for NCRs and indicate that a broader definition should be applied to pathological patterns recognized by innate immune receptors. Since nonmicrobial endogenous carbohydrate structures contribute significantly to this recognition, there is an imperative need to develop appropriate tools for the facile sequencing of carbohydrate moieties.

Crystallization of carbohydrate oxidase from Microdochium nivale

International Nuclear Information System (INIS)

Dušková, Jarmila; Dohnálek, Jan; Skálová, Tereza; Østergaard, Lars Henrik; Fuglsang, Claus Crone; Kolenko, Petr; Štěpánková, Andrea; Hašek, Jindřich

2009-01-01

Industrially used carbohydrate oxidase was successfully crystallized in several forms, diffraction data suitable for structural analysis were collected. Microdochium nivale carbohydrate oxidase was produced by heterologous recombinant expression in Aspergillus oryzae, purified and crystallized. The enzyme crystallizes with varying crystal morphologies depending on the crystallization conditions. Several different crystal forms were obtained using the hanging-drop vapour-diffusion method, two of which were used for diffraction measurements. Hexagon-shaped crystals (form I) diffracted to 2.66 Å resolution, with unit-cell parameters a = b = 55.7, c = 610.4 Å and apparent space group P6 2 22. Analysis of the data quality showed almost perfect twinning of the crystals. Attempts to solve the structure by molecular replacement did not give satisfactory results. Recently, clusters of rod-shaped crystals (form II) were grown in a solution containing PEG MME 550. These crystals belonged to the monoclinic system C2, with unit-cell parameters a = 132.9, b = 56.6, c = 86.5 Å, β = 95.7°. Data sets were collected to a resolution of 2.4 Å. The structure was solved by the molecular-replacement method. Model refinement is currently in progress

Compatible topologies and parameters for NMR structure determination of carbohydrates by simulated annealing

OpenAIRE

Feng, Yingang

2017-01-01

The use of NMR methods to determine the three-dimensional structures of carbohydrates and glycoproteins is still challenging, in part because of the lack of standard protocols. In order to increase the convenience of structure determination, the topology and parameter files for carbohydrates in the program Crystallography & NMR System (CNS) were investigated and new files were developed to be compatible with the standard simulated annealing protocols for proteins and nucleic acids. Recalculat...

Post-harvest treatments in smooth-stalked meadow grass (Poa pratensis L.) - effect on carbohydrates and tiller development

DEFF Research Database (Denmark)

Boelt, Birte

2007-01-01

Temperate grass species require a period of short days/low temperature to respond to flower induction stimuli. The same environmental conditions stimulate the increase in carbohydrate concentration in aboveground biomass and the accumulation of reserve carbohydrates in the basal plant parts....... The present investigation was initiated to investigate the effect of post-harvest treatments on dry matter production in autumn, carbohydrate content, the number of reproductive tillers and seed yield in a turf-type cultivar ‘Conni' of smooth-stalked meadow grass. The results show that post-harvest treatments...... harvest and all residues removed. The results from plant samples in autumn indicate that decreasing aboveground biomass production leads to a higher carbohydrate concentration which may stimulate the reproductive development in smooth-stalked meadow grass....

Differential effects of carbohydrates on arabidopsis pollen germination

Czech Academy of Sciences Publication Activity Database

Hirsche, J.; Fernández, J. M. G.; Stabentheiner, E.; Großkinsky, D.K.; Roitsch, Thomas

2017-01-01

Roč. 58, č. 4 (2017), s. 691-701 ISSN 0032-0781 R&D Projects: GA MŠk(CZ) LO1415 Institutional support: RVO:67179843 Keywords : Arabidopsis thaliana * Carbohydrates * Metabolic regulation * Pollen germination * Signaling * Structure-function relationship Subject RIV: EF - Botanics OBOR OECD: Cell biology Impact factor: 4.760, year: 2016

Seasonal changes in above- and belowground carbohydrate concentrations of ponderosa pine along a pollution gradient

Science.gov (United States)

Nancy E. Grulke; Chris P. Andersen; William E. Hogsett

2001-01-01

Seasonal patterns of carbohydrate concentration in coarse and fine roots, stem or bole, and foliage of ponderosa pine (Pinus ponderosa Laws) were described across five treeage classes from seedlings to mature trees at an atmospherically clean site. Relative to all other tree-age classes, seedlings exhibited greater tissue carbohydrate concentration...

Determination of glycaemic index; some methodological aspects related to the analysis of carbohydrate load and characteristics of the previous evening meal.

Science.gov (United States)

Granfeldt, Y; Wu, X; Björck, I

2006-01-01

To determine the possible differences in glycaemic index (GI) depending on (1) the analytical method used to calculate the 'available carbohydrate' load, that is, using carbohydrates by difference (total carbohydrate by difference, minus dietary fibre (DF)) as available carbohydrates vs available starch basis (total starch minus resistant starch (RS)) of a food rich in intrinsic RS and (2) the effect of GI characteristics and/or the content of indigestible carbohydrates (RS and DF) of the evening meal prior to GI testing the following morning. Blood glucose and serum insulin responses were studied after subjects consuming (1) two levels of barley kernels rich in intrinsic RS (15.2%, total starch basis) and (2) after a standard breakfast following three different evening meals varying in GI and/or indigestible carbohydrates: pasta, barley kernels and white wheat bread, respectively. Healthy adults with normal body mass index. (1) Increasing the portion size of barley kernels from 79.6 g (50 g 'available carbohydrates') to 93.9 g (50 g available starch) to adjust for its RS content did not significantly affect the GI or insulin index (11). (2) The low GI barley evening meal, as opposed to white wheat bread and pasta evening meals, reduced the postprandial glycaemic and insulinaemic (23 and 29%, respectively, P base carbohydrate load on specific analyses of the available carbohydrate content. (2) A low GI barley evening meal containing high levels of indigestible carbohydrates (RS and DF) substantially reduced the GI and II of white wheat bread determined at a subsequent breakfast meal.

Energy balance and hypothalamic effects of a high-protein/low-carbohydrate diet

OpenAIRE

Kinzig, Kimberly P.; Hargrave, Sara L.; Hyun, Jayson; Moran, Timothy H.

2007-01-01

Diets high in fat or protein and extremely low in carbohydrate are frequently reported to result in weight loss in humans. We previously reported that rats maintained on a low carbohydrate-high fat diet (LC-HF) consumed similar kcals/day as chow (CH)-fed rats and did not differ in body weight after 7 weeks. LC-HF rats had a 45% decrease in POMC expression in the ARC, decreased plasma insulin, and increased plasma leptin and ghrelin. In the present study we assessed the effects of a low carboh...

Metabolic Syndrome in Children: Clinical Picture, Features of Lipid and Carbohydrate Metabolism

Directory of Open Access Journals (Sweden)

O.S. Bobrykovych

2013-09-01

Full Text Available The study included 225 children aged from 14 to 18 years with various manifestations of the metabolic syndrome in neighborhoods, different by iodine provision. The physical development (height, weight, body mass index, waist and hip circumferences has been examined. Biochemical investigations are focused on the study of lipid and carbohydrate metabolism in children. It is found that children who live in mountains have more severe obesity. In parallel with the increase of the degree of obesity, disorders of lipid and carbohydrate metabolism aggravate in children with sings of metabolic syndrome.

Dietary carbohydrate in relation to cortical and nuclear lens opacities in the Melbourne Visual Impairment Project

Science.gov (United States)

PURPOSE: In vitro and in vivo animal studies suggest that dietary carbohydrates play a role in cataractogenesis. Few epidemiologic studies have been conducted to evaluate this association. The objective of this study was to examine the cross-sectional associations between total carbohydrate intake, ...

Synthetic Methods for Ester Bond Formation and Conformational Analysis of Ester-Containing Carbohydrates

Science.gov (United States)

Hackbusch, Sven

This dissertation encompasses work related to synthetic methods for the formation of ester linkages in organic compounds, as well as the investigation of the conformational influence of the ester functional group on the flexibility of inter-saccharide linkages, specifically, and the solution phase structure of ester-containing carbohydrate derivatives, in general. Stereoselective reactions are an important part of the field of asymmetric synthesis and an understanding of their underlying mechanistic principles is essential for rational method development. Here, the exploration of a diastereoselective O-acylation reaction on a trans-2-substituted cyclohexanol scaffold is presented, along with possible reasons for the observed reversal of stereoselectivity dependent on the presence or absence of an achiral amine catalyst. In particular, this work establishes a structure-activity relationship with regard to the trans-2-substituent and its role as a chiral auxiliary in the reversal of diastereoselectivity. In the second part, the synthesis of various ester-linked carbohydrate derivatives, and their conformational analysis is presented. Using multidimensional NMR experiments and computational methods, the compounds' solution-phase structures were established and the effect of the ester functional group on the molecules' flexibility and three-dimensional (3D) structure was investigated and compared to ether or glycosidic linkages. To aid in this, a novel Karplus equation for the C(sp2)OCH angle in ester-linked carbohydrates was developed on the basis of a model ester-linked carbohydrate. This equation describes the sinusoidal relationship between the C(sp2)OCH dihedral angle and the corresponding 3JCH coupling constant that can be determined from a J-HMBC NMR experiment. The insights from this research will be useful in describing the 3D structure of naturally occurring and lab-made ester-linked derivatives of carbohydrates, as well as guiding the de novo-design of

Exploring Cooperative Effects in Oxidative NHC Catalysis: Regioselective Acylation of Carbohydrates.

Science.gov (United States)

Cramer, David L; Bera, Srikrishna; Studer, Armido

2016-05-23

The utility of oxidative NHC catalysis for both the regioselective and chemoselective functionalization of carbohydrates is explored. Chiral NHCs allow for the highly regioselective oxidative esterification of various carbohydrates using aldehydes as acylation precursors. The transformation was also shown to be amenable to both cis/trans diol isomers, free amino groups, and selective for specific sugar epimers in competition experiments. Efficiency and regioselectivity of the acylation can be improved upon using two different NHC catalysts that act cooperatively. The potential of the method is documented by the regioselective acylation of an amino-linked neodisaccharide. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Science Study Aids 3: Carbohydrates - Nature's Energy Source.

Science.gov (United States)

McConnell, Bill

This publication is the third of a series of seven supplementary investigative materials for use in secondary science classes providing up-to-date research-related investigations. This unit is structured for grade levels 7 through 12. It is concerned with the role of carbohydrates as important nutrients for consumers. This guide will enable…

Carbohydrate, dietary glycaemic index and glycaemic load, and colorectal cancer risk: a case-control study in China.

Science.gov (United States)

Huang, Jing; Fang, Yu-Jing; Xu, Ming; Luo, Hong; Zhang, Nai-Qi; Huang, Wu-Qing; Pan, Zhi-Zhong; Chen, Yu-Ming; Zhang, Cai-Xia

2018-04-01

A carbohydrate-rich diet results in hyperglycaemia and hyperinsulinaemia; it may further induce the carcinogenesis of colorectal cancer. However, epidemiological evidence among Chinese population is quite limited. The aim of this study was to investigate total carbohydrate, non-fibre carbohydrate, total fibre, starch, dietary glycaemic index (GI) and glycaemic load (GL) in relation to colorectal cancer risk in Chinese population. A case-control study was conducted from July 2010 to April 2017, recruiting 1944 eligible colorectal cancer cases and 2027 age (5-year interval) and sex frequency-matched controls. Dietary information was collected by using a validated FFQ. The OR and 95 % CI of colorectal cancer risk were assessed by multivariable logistic regression models. There was no clear association between total carbohydrate intake and colorectal cancer risk. The adjusted OR was 0·85 (95 % CI 0·70, 1·03, P trend=0·08) comparing the highest with the lowest quartile. Total fibre was related to a 53 % reduction in colorectal cancer risk (adjusted ORquartile 4 v. 1 0·47; 95 % CI 0·39, 0·58). However, dietary GI was positively associated with colorectal cancer risk, with an adjusted ORquartile 4 v. 1 of 3·10 (95 % CI 2·51, 3·85). No significant association was found between the intakes of non-fibre carbohydrate, starch and dietary GL and colorectal cancer risk. This study indicated that dietary GI was positively associated with colorectal cancer risk, but no evidence supported that total carbohydrate, non-fibre carbohydrate, starch or high dietary GL intake were related to an increased risk of colorectal cancer in a Chinese population.

Ion mobility studies of carbohydrates as group I adducts: isomer specific collisional cross section dependence on metal ion radius.

Science.gov (United States)

Huang, Yuting; Dodds, Eric D

2013-10-15

Carbohydrates play numerous critical roles in biological systems. Characterization of oligosaccharide structures is essential to a complete understanding of their functions in biological processes; nevertheless, their structural determination remains challenging in part due to isomerism. Ion mobility spectrometry provides the means to resolve gas phase ions on the basis of their shape-to-charge ratios, thus providing significant potential for separation and differentiation of carbohydrate isomers. Here, we report on the determination of collisional cross sections for four groups of isomeric carbohydrates (including five isomeric disaccharides, four isomeric trisaccharides, two isomeric pentasaccharides, and two isomeric hexasaccharides) as their group I metal ion adducts (i.e., [M + Li](+), [M + Na](+), [M + K](+), [M + Rb](+), and [M + Cs](+)). In all, 65 collisional cross sections were measured, the great majority of which have not been previously reported. As anticipated, the collisional cross sections of the carbohydrate metal ion adducts generally increase with increasing metal ion radius; however, the collisional cross sections were found to scale with the group I cation size in isomer specific manners. Such measurements are of substantial analytical value, as they illustrate how the selection of charge carrier influences carbohydrate ion mobility determinations. For example, certain pairs of isomeric carbohydrates assume unique collisional cross sections upon binding one metal ion, but not another. On the whole, these data suggest a role for the charge carrier as a probe of carbohydrate structure and thus have significant implications for the continued development and application of ion mobility spectrometry for the distinction and resolution of isomeric carbohydrates.

Flight metabolism in Panstrongylus megistus (Hemiptera: Reduviidae): the role of carbohydrates and lipids