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Sample records for acids proteins carbohydrates

  1. Meal composition and plasma amino acid ratios: Effect of various proteins or carbohydrates, and of various protein concentrations

    NASA Technical Reports Server (NTRS)

    Yokogoshi, Hidehiko; Wurtman, Richard J.

    1986-01-01

    The effects of meals containing various proteins and carbohydrates, and of those containing various proportions of protein (0 percent to 20 percent of a meal, by weight) or of carbohydrate (0 percent to 75 percent), on plasma levels of certain large neutral amino acids (LNAA) in rats previously fasted for 19 hours were examined. Also the plasma tryptophan ratios (the ratio of the plasma trytophan concentration to the summed concentrations of the other large neutral amino acids) and other plasma amino acid ratios were calculated. (The plasma tryptophan ratio has been shown to determine brain tryptophan levels and, thereby, to affect the synthesis and release of the neurotransmitter serotonin). A meal containing 70 percent to 75 percent of an insulin-secreting carbohydrate (dextrose or dextrin) increased plasma insulin levels and the tryptophan ratio; those containing 0 percent or 25 percent carbohydrate failed to do so. Addition of as little as 5 percent casein to a 70 percent carbohydrate meal fully blocked the increase in the plasma tryptophan ratio without affecting the secretion of insulin - probably by contributing much larger quantities of the other LNAA than of tryptophan to the blood. Dietary proteins differed in their ability to suppress the carbohydrate-induced rise in the plasma tryptophan ratio. Addition of 10 percent casein, peanut meal, or gelatin fully blocked this increase, but lactalbumin failed to do so, and egg white did so only partially. (Consumption of the 10 percent gelatin meal also produced a major reduction in the plasma tyrosine ratio, and may thereby have affected brain tyrosine levels and catecholamine synthesis.) These observations suggest that serotonin-releasing neurons in brains of fasted rats are capable of distinguishing (by their metabolic effects) between meals poor in protein but rich in carbohydrates that elicit insulin secretion, and all other meals. The changes in brain serotonin caused by carbohydrate-rich, protein

  2. Effects on sialic acid recognition of amino acid mutations in the carbohydrate-binding cleft of the rotavirus spike protein.

    PubMed

    Kraschnefski, Mark J; Bugarcic, Andrea; Fleming, Fiona E; Yu, Xing; von Itzstein, Mark; Coulson, Barbara S; Blanchard, Helen

    2009-03-01

    The rotavirus spike protein VP4 mediates attachment to host cells and subsequent membrane penetration. The VP8(*) domain of VP4 forms the spike tips and is proposed to recognize host-cell surface glycans. For sialidase-sensitive rotaviruses such as rhesus (RRV), this recognition involves terminal sialic acids. We show here that the RRV VP8(*)(64-224) protein competes with RRV infection of host cells, demonstrating its relevance to infection. In addition, we observe that the amino acids revealed by X-ray crystallography to be in direct contact with the bound sialic acid derivative methyl alpha-D-N-acetylneuraminide, and that are highly conserved amongst sialidase-sensitive rotaviruses, are residues that are also important in interactions with host-cell carbohydrates. Residues Arg101 and Ser190 of the RRV VP8(*) carbohydrate-binding site were mutated to assess their importance for binding to the sialic acid derivative and their competition with RRV infection of host cells. The crystallographic structure of the Arg(101)Ala mutant crystallized in the presence of the sialic acid derivative was determined at 295 K to a resolution of 1.9 A. Our multidisciplinary study using X-ray crystallography, saturation transfer difference nuclear magnetic resonance spectroscopy, isothermal titration calorimetry, and competitive virus infectivity assays to investigate RRV wild-type and mutant VP8(*) proteins has provided the first evidence that the carbohydrate-binding cavity in RRV VP8(*) is used for host-cell recognition, and this interaction is not only with the sialic acid portion but also with other parts of the glycan structure.

  3. Hepatic fatty acid biosynthesis is more responsive to protein than carbohydrate in rainbow trout during acute stimulations.

    PubMed

    Dai, Weiwei; Panserat, Stéphane; Kaushik, Sadasivam; Terrier, Frédéric; Plagnes-Juan, Elisabeth; Seiliez, Iban; Skiba-Cassy, Sandrine

    2016-01-01

    The link between dietary carbohydrate/protein and de novo lipogenesis (DNL) remains debatable in carnivorous fish. We aimed to evaluate and compare the response of hepatic lipogenic gene expression to dietary carbohydrate intake/glucose and dietary protein intake/amino acids (AAs) during acute stimulations using both in vivo and in vitro approaches. For the in vivo trial, three different diets and a controlled-feeding method were employed to supply fixed amount of dietary protein or carbohydrate in a single meal; for the in vitro trial, primary hepatocytes were stimulated with a low or high level of glucose (3 mM or 20 mM) and a low or high level of AAs (one-fold or four-fold concentrated AAs). In vitro data showed that a high level of AAs upregulated the expression of enzymes involved in DNL [fatty acid synthase (FAS) and ATP citrate lyase (ACLY)], lipid bioconversion [elongation of very long chain fatty acids like-5 (Elovl5), Elovl2, Δ6 fatty acyl desaturase (D6D) and stearoyl-CoA desaturase-1 (SCD1)], NADPH production [glucose-6-phosphate dehydrogenase (G6PDH) and malic enzyme (ME)], and transcriptional factor sterol regulatory element binding protein 1-like, while a high level of glucose only elevated the expression of ME. Data in trout liver also showed that high dietary protein intake induced higher lipogenic gene expression (FAS, ACLY, and Elovl2) regardless of dietary carbohydrate intake, while high carbohydrate intake markedly suppressed the expression of acetyl-CoA carboxylase (ACC) and Elovl5. Overall, we conclude that, unlike rodents or humans, hepatic fatty acid biosynthetic gene expression in rainbow trout is more responsive to dietary protein intake/AAs than dietary carbohydrate intake/glucose during acute stimulations. This discrepancy probably represents one important physiological and metabolic difference between carnivores and omnivores. PMID:26491101

  4. Hepatic fatty acid biosynthesis is more responsive to protein than carbohydrate in rainbow trout during acute stimulations.

    PubMed

    Dai, Weiwei; Panserat, Stéphane; Kaushik, Sadasivam; Terrier, Frédéric; Plagnes-Juan, Elisabeth; Seiliez, Iban; Skiba-Cassy, Sandrine

    2016-01-01

    The link between dietary carbohydrate/protein and de novo lipogenesis (DNL) remains debatable in carnivorous fish. We aimed to evaluate and compare the response of hepatic lipogenic gene expression to dietary carbohydrate intake/glucose and dietary protein intake/amino acids (AAs) during acute stimulations using both in vivo and in vitro approaches. For the in vivo trial, three different diets and a controlled-feeding method were employed to supply fixed amount of dietary protein or carbohydrate in a single meal; for the in vitro trial, primary hepatocytes were stimulated with a low or high level of glucose (3 mM or 20 mM) and a low or high level of AAs (one-fold or four-fold concentrated AAs). In vitro data showed that a high level of AAs upregulated the expression of enzymes involved in DNL [fatty acid synthase (FAS) and ATP citrate lyase (ACLY)], lipid bioconversion [elongation of very long chain fatty acids like-5 (Elovl5), Elovl2, Δ6 fatty acyl desaturase (D6D) and stearoyl-CoA desaturase-1 (SCD1)], NADPH production [glucose-6-phosphate dehydrogenase (G6PDH) and malic enzyme (ME)], and transcriptional factor sterol regulatory element binding protein 1-like, while a high level of glucose only elevated the expression of ME. Data in trout liver also showed that high dietary protein intake induced higher lipogenic gene expression (FAS, ACLY, and Elovl2) regardless of dietary carbohydrate intake, while high carbohydrate intake markedly suppressed the expression of acetyl-CoA carboxylase (ACC) and Elovl5. Overall, we conclude that, unlike rodents or humans, hepatic fatty acid biosynthetic gene expression in rainbow trout is more responsive to dietary protein intake/AAs than dietary carbohydrate intake/glucose during acute stimulations. This discrepancy probably represents one important physiological and metabolic difference between carnivores and omnivores.

  5. Prolactin and the dietary protein/carbohydrate ratio regulate the expression of SNAT2 amino acid transporter in the mammary gland during lactation.

    PubMed

    Velázquez-Villegas, Laura A; López-Barradas, Adriana M; Torres, Nimbe; Hernández-Pando, Rogelio; León-Contreras, Juan Carlos; Granados, Omar; Ortíz, Victor; Tovar, Armando R

    2015-05-01

    The sodium coupled neutral amino acid transporter 2 (SNAT2/SAT2/ATA2) is expressed in the mammary gland (MG) and plays an important role in the uptake of alanine and glutamine which are the most abundant amino acids transported into this tissue during lactation. Thus, the aim of this study was to assess the amount and localization of SNAT2 before delivery and during lactation in rat MG, and to evaluate whether prolactin and the dietary protein/carbohydrate ratio might influence SNAT2 expression in the MG, liver and adipose tissue during lactation. Our results showed that SNAT2 protein abundance in the MG increased during lactation and this increase was maintained along this period, while 24 h after weaning it tended to decrease. To study the effect of prolactin on SNAT2 expression, we incubated MG explants or T47D cells transfected with the SNAT2 promoter with prolactin, and we observed in both studies an increase in the SNAT2 expression or promoter activity. Consumption of a high-protein/low carbohydrate diet increased prolactin concentration, with a concomitant increase in SNAT2 expression not only in the MG during lactation, but also in the liver and adipose tissue. There was a correlation between SNAT2 expression and serum prolactin levels depending on the amount of dietary protein/carbohydrate ratio consumed. These findings suggest that prolactin actively supports lactation providing amino acids to the gland through SNAT2 for the synthesis of milk proteins.

  6. Lower vegetable protein intake and higher dietary acid load associated with lower carbohydrate intake are risk factors for metabolic syndrome in patients with type 2 diabetes: Post-hoc analysis of a cross-sectional study

    PubMed Central

    Iwase, Hiroya; Tanaka, Muhei; Kobayashi, Yukiko; Wada, Sayori; Kuwahata, Masashi; Kido, Yasuhiro; Hamaguchi, Masahide; Asano, Mai; Yamazaki, Masahiro; Hasegawa, Goji; Nakamura, Naoto; Fukui, Michiaki

    2015-01-01

    Aims/Introduction A low-carbohydrate diet based on animal sources is associated with higher all-cause mortality, whereas a vegetable-based low-carbohydrate diet is associated with lower cardiovascular disease mortality. It has been suggested that acid/base imbalance might play an important role in some cardiometabolic abnormalities. The aims of the present study were to evaluate whether carbohydrate intake is associated with quality of dietary protein and acid load, and whether these are related to metabolic syndrome in patients with type 2 diabetes. Materials and Methods The present cross-sectional study involved 149 patients with type 2 diabetes. Dietary intake was assessed using a validated self-administered diet history questionnaire. Dietary acid load was assessed by potential renal acid load and net endogenous acid production. Results Mean daily total energy intake, carbohydrate intake, animal protein intake and vegetable protein intake were 1821.5 kcal, 248.8 g, 36.1 g and 31.1 g, respectively. Carbohydrate energy/total energy was negatively correlated with animal protein energy/total energy, potential renal acid load or net endogenous acid production score, and was positively correlated with vegetable protein energy/total energy. Logistic regression analyses showed that the subgroup of patients with a lower vegetable protein energy/total energy or higher potential renal acid load or net endogenous acid production score was significantly associated with the prevalence of metabolic syndrome. Conclusions The present study showed that carbohydrate intake was associated with the quality of dietary protein and dietary acid load. Furthermore, decreased vegetable protein intake and increased dietary acid load were associated with the prevalence of metabolic syndrome. PMID:26221526

  7. Characterizing carbohydrate-protein interactions by NMR

    PubMed Central

    Bewley, Carole A.; Shahzad-ul-Hussan, Syed

    2013-01-01

    Interactions between proteins and soluble carbohydrates and/or surface displayed glycans are central to countless recognition, attachment and signaling events in biology. The physical chemical features associated with these binding events vary considerably, depending on the biological system of interest. For example, carbohydrate-protein interactions can be stoichiometric or multivalent, the protein receptors can be monomeric or oligomeric, and the specificity of recognition can be highly stringent or rather promiscuous. Equilibrium dissociation constants for carbohydrate binding are known to vary from micromolar to millimolar, with weak interactions being far more prevalent; and individual carbohydrate binding sites can be truly symmetrical or merely homologous, and hence, the affinities of individual sites within a single protein can vary, as can the order of binding. Several factors, including the weak affinities with which glycans bind their protein receptors, the dynamic nature of the glycans themselves, and the non-equivalent interactions among oligomeric carbohydrate receptors, have made NMR an especially powerful tool for studying and defining carbohydrate-protein interactions. Here we describe those NMR approaches that have proven to be the most robust in characterizing these systems, and explain what type of information can (or cannot) be obtained from each. Our goal is to provide to the reader the information necessary for selecting the correct experiment or sets of experiments to characterize their carbohydrate-protein interaction of interest. PMID:23784792

  8. Carbohydrate Polymers for Nonviral Nucleic Acid Delivery

    PubMed Central

    Sizovs, Antons; McLendon, Patrick M.; Srinivasachari, Sathya

    2014-01-01

    Carbohydrates have been investigated and developed as delivery vehicles for shuttling nucleic acids into cells. In this review, we present the state of the art in carbohydrate-based polymeric vehicles for nucleic acid delivery, with the focus on the recent successes in preclinical models, both in vitro and in vivo. Polymeric scaffolds based on the natural polysaccharides chitosan, hyaluronan, pullulan, dextran, and schizophyllan each have unique properties and potential for modification, and these results are discussed with the focus on facile synthetic routes and favorable performance in biological systems. Many of these carbohydrates have been used to develop alternative types of biomaterials for nucleic acid delivery to typical polyplexes, and these novel materials are discussed. Also presented are polymeric vehicles that incorporate copolymerized carbohydrates into polymer backbones based on polyethylenimine and polylysine and their effect on transfection and biocompatibility. Unique scaffolds, such as clusters and polymers based on cyclodextrin (CD), are also discussed, with the focus on recent successes in vivo and in the clinic. These results are presented with the emphasis on the role of carbohydrate and charge on transfection. Use of carbohydrates as molecular recognition ligands for cell-type specific delivery is also briefly reviewed. We contend that carbohydrates have contributed significantly to progress in the field of non-viral DNA delivery, and these new discoveries are impactful for developing new vehicles and materials for treatment of human disease. PMID:21504102

  9. Advances in Food Composition Tables of Japan--Amino Acid, Fatty Acid and Available Carbohydrate Tables.

    PubMed

    Yasui, Takeshi

    2015-01-01

    The new revised version of the Standard Tables of Food Composition in Japan (STFCJ 2015) will be published in 2015. The aim of the present paper is to share information on issues we have encountered during the revision. New analytical data on amino acid composition will be provided for approximately 230 foods, fatty acid composition for approximately 140 foods, and available carbohydrate (starch, glucose, fructose, sucrose, maltose, and lactose) composition for approximately 340 foods. These data will be published separately as three supplements to the STFCJ 2015: amino acid tables, fatty acid tables, and available carbohydrate tables. Available carbohydrate tables will also provide polyol (sorbitol and mannitol) and organic acid (acetic acid, lactic acid, citric acid, etc.) data. In the supplements, amino acid content will be adjusted for protein content calculated as reference nitrogen multiplied by a nitrogen to protein conversion factor, and fatty acid content adjusted for extractable lipid content, as in previous revisions. Available carbohydrate content, however, will be adjusted for water content. Values of protein content calculated as the sum of amino acid residues , lipid content expressed as triacylglycerol equivalents of fatty acids , and available carbohydrate content will appear in the main tables of the STFCJ 2015. Protein, fat and available carbohydrate contents were significantly decreased when the preferred analytical methods of FAO were applied instead of the acceptable methods. Online publication of Japanese and English versions of these tables, reference materials, and a retrievable food composition database is planned. PMID:26598876

  10. The mitochondrial sulfur dioxygenase ETHYLMALONIC ENCEPHALOPATHY PROTEIN1 is required for amino acid catabolism during carbohydrate starvation and embryo development in Arabidopsis.

    PubMed

    Krüßel, Lena; Junemann, Johannes; Wirtz, Markus; Birke, Hannah; Thornton, Jeremy D; Browning, Luke W; Poschet, Gernot; Hell, Rüdiger; Balk, Janneke; Braun, Hans-Peter; Hildebrandt, Tatjana M

    2014-05-01

    The sulfur dioxygenase ETHYLMALONIC ENCEPHALOPATHY PROTEIN1 (ETHE1) catalyzes the oxidation of persulfides in the mitochondrial matrix and is essential for early embryo development in Arabidopsis (Arabidopsis thaliana). We investigated the biochemical and physiological functions of ETHE1 in plant metabolism using recombinant Arabidopsis ETHE1 and three transfer DNA insertion lines with 50% to 99% decreased sulfur dioxygenase activity. Our results identified a new mitochondrial pathway catalyzing the detoxification of reduced sulfur species derived from cysteine catabolism by oxidation to thiosulfate. Knockdown of the sulfur dioxygenase impaired embryo development and produced phenotypes of starvation-induced chlorosis during short-day growth conditions and extended darkness, indicating that ETHE1 has a key function in situations of high protein turnover, such as seed production and the use of amino acids as alternative respiratory substrates during carbohydrate starvation. The amino acid profile of mutant plants was similar to that caused by defects in the electron-transfer flavoprotein/electron-transfer flavoprotein:ubiquinone oxidoreductase complex and associated dehydrogenases. Thus, in addition to sulfur amino acid catabolism, ETHE1 also affects the oxidation of branched-chain amino acids and lysine.

  11. The Mitochondrial Sulfur Dioxygenase ETHYLMALONIC ENCEPHALOPATHY PROTEIN1 Is Required for Amino Acid Catabolism during Carbohydrate Starvation and Embryo Development in Arabidopsis1[C][W

    PubMed Central

    Krüßel, Lena; Junemann, Johannes; Wirtz, Markus; Birke, Hannah; Thornton, Jeremy D.; Browning, Luke W.; Poschet, Gernot; Hell, Rüdiger; Balk, Janneke; Braun, Hans-Peter; Hildebrandt, Tatjana M.

    2014-01-01

    The sulfur dioxygenase ETHYLMALONIC ENCEPHALOPATHY PROTEIN1 (ETHE1) catalyzes the oxidation of persulfides in the mitochondrial matrix and is essential for early embryo development in Arabidopsis (Arabidopsis thaliana). We investigated the biochemical and physiological functions of ETHE1 in plant metabolism using recombinant Arabidopsis ETHE1 and three transfer DNA insertion lines with 50% to 99% decreased sulfur dioxygenase activity. Our results identified a new mitochondrial pathway catalyzing the detoxification of reduced sulfur species derived from cysteine catabolism by oxidation to thiosulfate. Knockdown of the sulfur dioxygenase impaired embryo development and produced phenotypes of starvation-induced chlorosis during short-day growth conditions and extended darkness, indicating that ETHE1 has a key function in situations of high protein turnover, such as seed production and the use of amino acids as alternative respiratory substrates during carbohydrate starvation. The amino acid profile of mutant plants was similar to that caused by defects in the electron-transfer flavoprotein/electron-transfer flavoprotein:ubiquinone oxidoreductase complex and associated dehydrogenases. Thus, in addition to sulfur amino acid catabolism, ETHE1 also affects the oxidation of branched-chain amino acids and lysine. PMID:24692429

  12. Boronic acids for fluorescence imaging of carbohydrates.

    PubMed

    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.

  13. Co-ingestion of carbohydrate with leucine-enriched essential amino acids does not augment acute postexercise muscle protein synthesis in a strenuous exercise-induced hypoinsulinemic state.

    PubMed

    Kato, Hiroyuki; Suzuki, Hiromi; Inoue, Yoshiko; Takimoto, Tetsuya; Suzuki, Katsuya; Kobayashi, Hisamine

    2016-01-01

    Strenuous exercise following overnight fasting increases fat oxidation during exercise, which can modulate training adaptation. However, such exercise induces muscle protein catabolism by decreasing blood insulin concentrations and increasing amino acid oxidation during the exercise. Leucine-enriched essential amino acids (LEAAs) enhance muscle protein synthesis (MPS) at rest and after exercise. However, it remains to be clarified if the co-ingestion of carbohydrate with LEAAs induces an additional increase in MPS, particularly in a hypoinsulinemic state induced by strenuous exercise. Eight-week-old male Sprague-Dawley rats were made to perform strenuous jump exercise (height 35 cm, 200 jumps, 3-s intervals), after which they ingested distilled water and 1 g/kg LEAAs with or without 1 g/kg of glucose. The fractional synthesis rate was determined by measuring the incorporation of l-[ring-(2)H5]-phenylalanine into skeletal muscle protein. Immediately after the exercise, plasma insulin concentration was significantly lower than that at the basal level. Co-ingestion of glucose with LEAAs alleviated the reduction in plasma insulin concentration, while LEAA ingestion alone did not. LEAA administration with or without glucose led to a higher MPS compared with water administration (P < 0.05). However, the co-ingestion of glucose with LEAAs did not induce further increases in MPS compared with LEAA ingestion alone. Thus, the co-ingestion of glucose with LEAAs does not additionally increase MPS under a strenuous exercise-induced hypoinsulinemic state when glucose is co-ingested with a dose of LEAAs that maximally stimulates MPS. PMID:27547673

  14. Increased net muscle protein balance in response to simultaneous and separate ingestion of carbohydrate and essential amino acids following resistance exercise.

    PubMed

    Witard, Oliver C; Cocke, Tara L; Ferrando, Arny A; Wolfe, Robert R; Tipton, Kevin D

    2014-03-01

    Relative to essential amino acids (EAAs), carbohydrate (CHO) ingestion stimulates a delayed response of net muscle protein balance (NBAL). We investigated if staggered ingestion of CHO and EAA would superimpose the response of NBAL following resistance exercise, thus resulting in maximal anabolic stimulation. Eight recreationally trained subjects completed 2 trials: combined (COMB - drink 1, CHO+EAA; drink 2, placebo) and separated (SEP - drink 1, CHO; drink 2, EAA) post-exercise ingestion of CHO and EAA. Drink 1 was administered 1 h following an acute exercise bout and was followed 1 h later by drink 2. A primed, continuous infusion of l-[ring-(13)C6]-phenylalanine was combined with femoral arteriovenous sampling and muscle biopsies for the determination of muscle protein kinetics. Arterial amino acid concentrations increased following ingestion of EAA in both conditions. No difference between conditions was observed for phenylalanine delivery to the leg (COMB: 167 ± 23 μmol·min(-1)·(100 mL leg vol)(-1) × 6 h; SEP: 167 ± 21 μmol·min(-1)·(100 mL leg vol)(-1) × 6 h, P > 0.05). In the first hour following ingestion of the drink containing EAA, phenylalanine uptake was 50% greater for the SEP trial than the COMB trial. However, phenylalanine uptake was similar for COMB (110 ± 19 mg) and SEP (117 ± 24 mg) over the 6 h period. These data suggest that whereas separation of CHO and EAA ingestion following exercise may have a transient physiological impact on NBAL, this response is not reflected over a longer period. Thus, separation of CHO and EAA ingestion is unnecessary to optimize post-exercise muscle protein metabolism.

  15. Impact of Dietary Carbohydrate and Protein Levels on Carbohydrate Metabolism

    ERIC Educational Resources Information Center

    Lasker, Denise Ann

    2009-01-01

    The goal of this dissertation was to investigate the impact of changing dietary carbohydrate (CARB) intakes within recommended dietary guidelines on metabolic outcomes specifically associated with glycemic regulations and carbohydrate metabolism. This research utilized both human and animal studies to examine changes in metabolism across a wide…

  16. Effects of abscisic acid, ethylene and sugars on the mobilization of storage proteins and carbohydrates in seeds of the tropical tree Sesbania virgata (Leguminosae)

    PubMed Central

    Tonini, Patricia Pinho; Purgatto, Eduardo; Buckeridge, Marcos Silveira

    2010-01-01

    Background and Aims Endospermic legumes are abundant in tropical forests and their establishment is closely related to the mobilization of cell-wall storage polysaccharides. Endosperm cells also store large numbers of protein bodies that play an important role as a nitrogen reserve in this seed. In this work, a systems approach was adopted to evaluate some of the changes in carbohydrates and hormones during the development of seedlings of the rain forest tree Sesbania virgata during the period of establishment. Methods Seeds imbibed abscisic acid (ABA), glucose and sucrose in an atmosphere of ethylene, and the effects of these compounds on the protein contents, α-galactosidase activity and endogenous production of ABA and ethylene by the seeds were observed. Key Results The presence of exogenous ABA retarded the degradation of storage protein in the endosperm and decreased α-galactosidase activity in the same tissue during galactomannan degradation, suggesting that ABA represses enzyme action. On the other hand, exogenous ethylene increased α-galactosidase activity in both the endosperm and testa during galactomannan degradation, suggesting an inducing effect of this hormone on the hydrolytic enzymes. Furthermore, the detection of endogenous ABA and ethylene production during the period of storage mobilization and the changes observed in the production of these endogenous hormones in the presence of glucose and sucrose, suggested a correlation between the signalling pathway of these hormones and the sugars. Conclusions These findings suggest that ABA, ethylene and sugars play a role in the control of the hydrolytic enzyme activities in seeds of S. virgata, controlling the process of storage degradation. This is thought to ensure a balanced flow of the carbon and nitrogen for seedling development. PMID:20705626

  17. Carbohydrates.

    PubMed

    Cocinero, Emilio J; Çarçabal, Pierre

    2015-01-01

    Although carbohydrates represent one of the most important families of biomolecules, they remain under-studied in comparison to the other biomolecular families (peptides, nucleobases). Beyond their best-known function of energy source in living systems, they act as mediator of molecular recognition processes, carrying molecular information in the so-called "sugar code," just to name one of their countless functions. Owing to their high conformational flexibility, they encode extremely rich information conveyed via the non-covalent hydrogen bonds within the carbohydrate and with other biomolecular assemblies, such as peptide subunits of proteins. Over the last decade there has been tremendous progress in the study of the conformational preferences of neutral oligosaccharides, and of the interactions between carbohydrates and various molecular partners (water, aromatic models, and peptide models), using vibrational spectroscopy as a sensitive probe. In parallel, other spectroscopic techniques have recently become available to the study of carbohydrates in the gas phase (microwave spectroscopy, IRMPD on charged species).

  18. A functional carbohydrate chip platform for analysis of carbohydrate-protein interaction

    NASA Astrophysics Data System (ADS)

    Seo, Jeong Hyun; Kim, Chang Sup; Hwang, Byeong Hee; Cha, Hyung Joon

    2010-05-01

    A carbohydrate chip based on glass or other transparent surfaces has been suggested as a potential tool for high-throughput analysis of carbohydrate-protein interactions. Here we proposed a facile, efficient, and cost-effective method whereby diverse carbohydrate types are modified in a single step and directly immobilized onto a glass surface, with retention of functional orientation. We modified various types of carbohydrates by reductive amination, in which reducing sugar groups were coupled with 4-(2-aminoethyl)aniline, which has di-amine groups at both ends. The modified carbohydrates were covalently attached to an amino-reactive NHS-activated glass surface by formation of stable amide bonds. This proposed method was applied for efficient construction of a carbohydrate microarray to analyze carbohydrate-protein interactions. The carbohydrate chip prepared using our method can be successfully used in diverse biomimetic studies of carbohydrates, including carbohydrate-biomolecule interactions, and carbohydrate sensor chip or microarray development for diagnosis and screening.

  19. Analysis of Carbohydrate and Fatty Acid Marker Abundance in Ricin Toxin Preparations for Forensic Information

    SciTech Connect

    Colburn, Heather A.; Wunschel, David S.; Kreuzer-Martin, Helen W.; Moran, James J.; Antolick, Kathryn C.; Melville, Angela M.

    2010-07-15

    One challenge in the forensic analysis of ricin samples is determining the method and extent of sample preparation. Ricin purification from the source castor seeds is essentially a protein purification through removal of the non-protein fractions of the seed. Two major, non-protein constituents in the seed are the castor oil and carbohydrates. Ricinoleic acid is a relatively unique fatty acid in nature and is the most abundant component of castor oil, which comprises roughly half the seed weight. The carbohydrate component comprises roughly half of the remaining “mash” left after oil and hull removal. We used derivatization of carbohydrate and fatty acid markers followed by identification and quantification using gas chromatography/mass spectrometry (GC/MS) to assess compositional changes in ricin samples purified by different methods. The loss of ricinoleic acid indicated steps for oil removal had occurred. Changes to the carbohydrate content of the sample were also observed following protein precipitation. The differential loss of arabinose relative to mannose indicated removal of the major carbohydrate fraction of the seed and enrichment of the protein content. Taken together, these changes in fatty acid and carbohydrate abundance are indicative of the preparation method used for each sample.

  20. Arabinogalactan proteins: focus on carbohydrate active enzymes

    PubMed Central

    Knoch, Eva; Dilokpimol, Adiphol; Geshi, Naomi

    2014-01-01

    Arabinogalactan proteins (AGPs) are a highly diverse class of cell surface proteoglycans that are commonly found in most plant species. AGPs play important roles in many cellular processes during plant development, such as reproduction, cell proliferation, pattern formation and growth, and in plant-microbe interaction. However, little is known about the molecular mechanisms of their function. Numerous studies using monoclonal antibodies that recognize different AGP glycan epitopes have shown the appearance of a slightly altered AGP glycan in a specific stage of development in plant cells. Therefore, it is anticipated that the biosynthesis and degradation of AGP glycan is tightly regulated during development. Until recently, however, little was known about the enzymes involved in the metabolism of AGP glycans. In this review, we summarize recent discoveries of carbohydrate active enzymes (CAZy; http://www.cazy.org/) involved in the biosynthesis and degradation of AGP glycans, and we discuss the biological role of these enzymes in plant development. PMID:24966860

  1. Degradation properties of protein and carbohydrate during sludge anaerobic digestion.

    PubMed

    Yang, Guang; Zhang, Panyue; Zhang, Guangming; Wang, Yuanyuan; Yang, Anqi

    2015-09-01

    Degradation of protein and carbohydrate is vital for sludge anaerobic digestion performance. However, few studies focused on degradation properties of protein and carbohydrate. This study investigated detailed degradation properties of sludge protein and carbohydrate in order to gain insight into organics removal during anaerobic digestion. Results showed that carbohydrate was more efficiently degraded than protein and was degraded prior to protein. The final removal efficiencies of carbohydrate and protein were 49.7% and 32.2%, respectively. The first 3 days were a lag phase for protein degradation since rapid carbohydrate degradation in this phase led to repression of protease formation. Kinetics results showed that, after initial lag phase, protein degradation followed the first-order kinetic with rate constants of 0.0197 and 0.0018 d(-1) during later rapid degradation phase and slow degradation phase, respectively. Carbohydrate degradation also followed the first-order kinetics with a rate constant of 0.007 d(-1) after initial quick degradation phase.

  2. Multicomponent cascade reactions of unprotected carbohydrates and amino acids.

    PubMed

    Voigt, Benjamin; Linke, Michael; Mahrwald, Rainer

    2015-06-01

    Herein an operationally simple multicomponent reaction of unprotected carbohydrates with amino acids and isonitriles is presented. By the extension of this Ugi-type reaction to an unprotected disaccharide a novel glycopeptide structure was accessible.

  3. Increased intestinal amino-acid retention from the addition of carbohydrates to a meal.

    PubMed

    Deutz, N E; Ten Have, G A; Soeters, P B; Moughan, P J

    1995-12-01

    Carbohydrates, added to a protein meal, are known to enhance the efficiency of dietary protein utilisation. However, the respective roles of the gut and liver in relation to this enhanced efficiency are not known. Therefore, we studied amino-acid, ammonia, urea, glucose and lactate fluxes for 6 h across the portal drained viscera and liver in conscious, multi-catheterised pigs of approximately 25 kg body weight after receiving a protein meal with added carbohydrates, a pure protein meal or a control meal. Additional carbohydrate caused a net glucose efflux in the portal drained viscera and increased arterial blood insulin levels. The appearance of amino-acids in the portal blood declined by some 30%, in spite of the dietary true amino-acid digestibility being approximately 95%. Liver uptake of most amino-acids was lower and there was a lower liver urea production. Finally, there was a smaller postprandial increase in the arterial blood concentration for most of the amino-acids. The results of this study suggest that inclusion of maltodextrin in the diet increases the net retention of meal-derived amino-acids in the portal drained viscera. The lower urea production and liver amino-acid uptake suggest a lower nitrogen loss. The gut could be an important site for nitrogen retention induced by the addition of carbohydrates to a protein meal.

  4. Validation of lignocellulosic biomass carbohydrates determination via acid hydrolysis.

    PubMed

    Zhou, Shengfei; Runge, Troy M

    2014-11-01

    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.

  5. The skinny on high-protein, low-carbohydrate diets.

    PubMed

    Cunningham, Wendy; Hyson, Dianne

    2006-01-01

    Short-term studies of high-protein, low-carbohydrate diets have shown weight loss and improvements in plasma lipid profiles. Studies of greater than 6 months' duration, however, have failed to show continued benefit of high-protein, low-carbohydrate diets on weight loss and cardiovascular risk factors compared with conventional diets. Without concurrent weight loss and caloric restriction, these diets offer no additional benefit to lipids or body weight over other weight-loss regimens. In fact, high-protein, low-carbohydrate diets may add additional risk to individuals with cardiovascular disease due to their high fat and cholesterol content combined with decreased intake of fruits, vegetables, whole grains, and other nutrients related to cardiovascular risk. In addition, high-protein, low-carbohydrate diets have been implicated in other risks, including impaired renal, bone, and gastrointestinal health.

  6. Carbohydrates

    MedlinePlus

    Carbohydrates are one of the main types of nutrients. They are the most important source of energy for your body. Your digestive system changes carbohydrates into glucose (blood sugar). Your body uses this ...

  7. Collective choice in ants: the role of protein and carbohydrates ratios.

    PubMed

    Arganda, S; Nicolis, S C; Perochain, A; Péchabadens, C; Latil, G; Dussutour, A

    2014-10-01

    In a foraging context, social insects make collective decisions from individuals responding to local information. When faced with foods varying in quality, ants are known to be able to select the best food source using pheromone trails. Until now, studies investigating collective decisions have focused on single nutrients, mostly carbohydrates. In the environment, the foods available are a complex mixture and are composed of various nutrients, available in different forms. In this paper, we explore the effect of protein to carbohydrate ratio on ants' ability to detect and choose between foods with different protein characteristics (free amino acids or whole proteins). In a two-choice set up, Argentine ants Linepithema humile were presented with two artificial foods containing either whole protein or amino acids in two different dietary conditions: high protein food or high carbohydrate food. At the collective level, when ants were faced with high carbohydrate foods, they did not show a preference between free amino acids or whole proteins, while a preference for free amino acids emerged when choosing between high protein foods. At the individual level, the probability of feeding was higher for high carbohydrates food and for foods containing free amino acids. Two mathematical models were developed to evaluate the importance of feeding probability in collective food selection. A first model in which a forager deposits pheromone only after feeding, and a second model in which a forager always deposits pheromone, but with greater intensity after feeding. Both models were able to predict free amino acid selection, however the second one was better able to reproduce the experimental results suggesting that modulating trail strength according to feeding probability is likely the mechanism explaining amino acid preference at a collective level in Argentine ants.

  8. ANALYSIS OF RICIN TOXIN PREPARATIONS FOR CARBOHYDRATE AND FATTY ACID ABUNDANCE AND ISOTOPE RATIO INFORMATION

    SciTech Connect

    Wunschel, David S.; Kreuzer-Martin, Helen W.; Antolick, Kathryn C.; Colburn, Heather A.; Moran, James J.; Melville, Angela M.

    2009-12-01

    This report describes method development and preliminary evaluation for analyzing castor samples for signatures of purifying ricin. Ricin purification from the source castor seeds is essentially a problem of protein purification using common biochemical methods. Indications of protein purification will likely manifest themselves as removal of the non-protein fractions of the seed. Two major, non-protein, types of biochemical constituents in the seed are the castor oil and various carbohydrates. The oil comprises roughly half the seed weight while the carbohydrate component comprises roughly half of the remaining “mash” left after oil and hull removal. Different castor oil and carbohydrate components can serve as indicators of specific toxin processing steps. Ricinoleic acid is a relatively unique fatty acid in nature and is the most abundant component of castor oil. The loss of ricinoleic acid indicates a step to remove oil from the seeds. The relative amounts of carbohydrates and carbohydrate-like compounds, including arabinose, xylose, myo-inositol fucose, rhamnose, glucosamine and mannose detected in the sample can also indicate specific processing steps. For instance, the differential loss of arabinose relative to mannose and N-acetyl glucosamine indicates enrichment for the protein fraction of the seed using protein precipitation. The methods developed in this project center on fatty acid and carbohydrate extraction from castor samples followed by derivatization to permit analysis by gas chromatography-mass spectrometry (GC-MS). Method descriptions herein include: the source and preparation of castor materials used for method evaluation, the equipment and description of procedure required for chemical derivatization, and the instrument parameters used in the analysis. Two types of derivatization methods describe analysis of carbohydrates and one procedure for analysis of fatty acids. Two types of GC-MS analysis is included in the method development, one

  9. CHARMM additive all-atom force field for carbohydrate derivatives and its utility in polysaccharide and carbohydrate-protein modeling

    PubMed Central

    Guvench, Olgun; Mallajosyula, Sairam S.; Raman, E. Prabhu; Hatcher, Elizabeth; Vanommeslaeghe, Kenno; Foster, Theresa J.; Jamison, Francis W.; MacKerell, Alexander D.

    2011-01-01

    Monosaccharide derivatives such as xylose, fucose, N-acetylglucosamine (GlcNAc), N-acetylgalactosamine (GlaNAc), glucuronic acid, iduronic acid, and N-acetylneuraminic acid (Neu5Ac) are important components of eukaryotic glycans. The present work details development of force-field parameters for these monosaccharides and their covalent connections to proteins via O-linkages to serine or threonine sidechains and via N-linkages to asparagine sidechains. The force field development protocol was designed to explicitly yield parameters that are compatible with the existing CHARMM additive force field for proteins, nucleic acids, lipids, carbohydrates, and small molecules. Therefore, when combined with previously developed parameters for pyranose and furanose monosaccharides, for glycosidic linkages between monosaccharides, and for proteins, the present set of parameters enables the molecular simulation of a wide variety of biologically-important molecules such as complex carbohydrates and glycoproteins. Parametrization included fitting to quantum mechanical (QM) geometries and conformational energies of model compounds, as well as to QM pair interaction energies and distances of model compounds with water. Parameters were validated in the context of crystals of relevant monosaccharides, as well NMR and/or x-ray crystallographic data on larger systems including oligomeric hyaluronan, sialyl Lewis X, O- and N-linked glycopeptides, and a lectin:sucrose complex. As the validated parameters are an extension of the CHARMM all-atom additive biomolecular force field, they further broaden the types of heterogeneous systems accessible with a consistently-developed force-field model. PMID:22125473

  10. Amino Acid Change in the Carbohydrate Response Element Binding Protein is associated with lower triglycerides and myocardial infarction incidence depending on level of adherence to the Mediterranean diet in the PREDIMED trial

    Technology Transfer Automated Retrieval System (TEKTRAN)

    A variant (rs3812316, C771G, and Gln241His) in the MLXIPL (Max-like protein X interacting protein-like) gene encoding the carbohydrate response element binding protein has been associated with lower triglycerides. However, its association with cardiovascular diseases and gene-diet interactions modul...

  11. Characterization of carbohydrate-protein matrices for nutrient delivery.

    PubMed

    Zhou, Yankun; Roos, Yrjö H

    2011-05-01

    Amorphous carbohydrates may show glass transition and crystallization as a result of thermal or water plasticization. Proteins often affect the state transitions of carbohydrates in carbohydrate-protein systems. Water sorption behavior and effects of water on glass transition and crystallization in freeze-dried lactose, trehalose, lactose-casein (3: 1), lactose-soy protein isolate (3:1), trehalose-casein (3:1), and trehalose-soy protein isolate (3:1) systems were studied. Water sorption was determined gravimetrically as a function of time, and Brunauer-Emmett-Teller (BET) and Guggenheim-Anderson-de Boer (GAB) models were fitted to the experimental data. Glass transition temperature (T(g)) and instant crystallization temperature (T(ic)) in anhydrous and water plasticized systems were measured using differential scanning calorimetry (DSC). The Gordon-Taylor equation was used to model water content dependence of the T(g) values. The critical water content and water activity (a(w)) at 24 °C were calculated and crystallization of lactose and trehalose in the systems was followed at and above 0.54 a(w). Carbohydrate-protein systems showed higher amounts of sorbed water and less rapid sugar crystallization than pure sugars. A greater sugar crystallization delay was found in carbohydrate-casein systems than in carbohydrate-soy protein isolate systems. The T(g) and T(ic) values decreased with increasing water content and a(w). However, higher T(ic) values for lactose-protein systems were found than for lactose at the same a(w). Trehalose showed lower T(ic) value than lactose at 0.44 a(w) but no instant crystallization was measured below 0.44 a(w). State diagrams for each system are useful in selecting processing parameters and storage conditions in nutrient delivery applications. PMID:22417357

  12. Interactions of polyphenols with carbohydrates, lipids and proteins.

    PubMed

    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. PMID:25577120

  13. Interactions of polyphenols with carbohydrates, lipids and proteins.

    PubMed

    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.

  14. A high-protein, high-fat, carbohydrate-free diet reduces energy intake, hepatic lipogenesis, and adiposity in rats.

    PubMed

    Pichon, Lisa; Huneau, Jean-François; Fromentin, Gilles; Tomé, Daniel

    2006-05-01

    The aim of this work was to determine the effects in rats of ingesting 1 of 3 diets with normal or high protein concentrations and various carbohydrate:lipid ratios on weight gain, body composition, and the development and metabolism of white adipose tissue (WAT). For this purpose, male Wistar rats were fed for 20 or 42 d a high-carbohydrate, low-fat, normal-protein diet (76, 10, and 14% of energy as carbohydrate, lipid, and protein, respectively, carbohydrate:lipid ratio (C/L) = 7.6), a normal-carbohydrate, low-fat, high-protein diet (35, 10, and 55% of energy as carbohydrate, lipid, and protein respectively, C:L = 3.5), or a carbohydrate-free, high-fat, high-protein diet (45 and 55% of energy as fat and protein, respectively, C:L = 0). Growth, food intake, body composition, WAT cellularity, and several markers of lipogenesis including fatty acid synthase and lipoprotein lipase activities were measured in adipose tissue and liver. Lowering the C:L ratio reduced the development of WAT, weight gain, body fat mass, and adipocyte size, and in rats fed the carbohydrate-free diet (C:L = 0), the total number of adipocytes in subcutaneous WAT. These reductions in adipose tissue development with decreases in the C:L ratio of the diet seemed to be due primarily to reduced hepatic lipogenesis.

  15. Catalytical Conversion of Carbohydrates into Lactic Acid via Hydrothermal Reaction

    NASA Astrophysics Data System (ADS)

    Wei, Zhen; Jin, Fangming; Zhang, Guangyi; Zhang, Shiping; Yao, Guodong

    2010-11-01

    This paper focuses on catalytical conversion of carbohydrates into lactic acid, under the hydrothermal conditions, which may have a promising future for its high speediness and effectiveness. The catalysis of ZnO was investigated to improve the lactic acid yields. The results showed that the lactic acid yields increased immensely by the addition of ZnO. The effects of the reaction time and the addition amount of ZnO on the conversion of carbohydrates to lactic acid were studied. The highest lactic acid yields reached up to 28% starting from glucose after the reaction time of 60 s under the conditions of 0.2 mmol ZnO, 300° C, the filling rate of 35%, and over 30% starting from fructose at the same temperature and filling rate when the reaction time of 40 s and 2.0 mmol ZnO were employed. The collaborative effects of ZnO and NaOH used as the catalysts together at the same time were also studied. Furthermore, the catalytic mechanism of ZnO in the hydrothermal conversion of carbohydrates into lactic acid was discussed.

  16. The statolith compartment in Chara rhizoids contains carbohydrate and protein

    NASA Technical Reports Server (NTRS)

    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.

  17. Effects of carbohydrate, protein and lipid content of organic waste on hydrogen production and fermentation products.

    PubMed

    Alibardi, Luca; Cossu, Raffaello

    2016-01-01

    Organic waste from municipalities, food waste and agro-industrial residues are ideal feedstocks for use in biological conversion processes in biorefinery chains, representing biodegradable materials containing a series of substances belonging to the three main groups of the organic matter: carbohydrates, proteins and lipids. Biological hydrogen production by dark fermentation may assume a central role in the biorefinery concept, representing an up-front treatment for organic waste capable of hydrolysing complex organics and producing biohydrogen. This research study was aimed at evaluating the effects of carbohydrate, protein and lipid content of organic waste on hydrogen yields, volatile fatty acid production and carbon-fate. Biogas and hydrogen productions were linearly correlated to carbohydrate content of substrates while proteins and lipids failed to produce significant contributions. Chemical composition also produced effects on the final products of dark fermentation. Acetic and butyric acids were the main fermentation products, with their ratio proving to correlate with carbohydrate and protein content. The results obtained in this research study enhance the understanding of data variability on hydrogen yields from organic waste. Detailed information on waste composition and chemical characterisation are essential to clearly identify the potential performances of the dark fermentation process.

  18. Effects of carbohydrate, protein and lipid content of organic waste on hydrogen production and fermentation products.

    PubMed

    Alibardi, Luca; Cossu, Raffaello

    2016-01-01

    Organic waste from municipalities, food waste and agro-industrial residues are ideal feedstocks for use in biological conversion processes in biorefinery chains, representing biodegradable materials containing a series of substances belonging to the three main groups of the organic matter: carbohydrates, proteins and lipids. Biological hydrogen production by dark fermentation may assume a central role in the biorefinery concept, representing an up-front treatment for organic waste capable of hydrolysing complex organics and producing biohydrogen. This research study was aimed at evaluating the effects of carbohydrate, protein and lipid content of organic waste on hydrogen yields, volatile fatty acid production and carbon-fate. Biogas and hydrogen productions were linearly correlated to carbohydrate content of substrates while proteins and lipids failed to produce significant contributions. Chemical composition also produced effects on the final products of dark fermentation. Acetic and butyric acids were the main fermentation products, with their ratio proving to correlate with carbohydrate and protein content. The results obtained in this research study enhance the understanding of data variability on hydrogen yields from organic waste. Detailed information on waste composition and chemical characterisation are essential to clearly identify the potential performances of the dark fermentation process. PMID:26254676

  19. Recovery from cycling exercise: effects of carbohydrate and protein beverages.

    PubMed

    Goh, Qingnian; Boop, Christopher A; Luden, Nicholas D; Smith, Alexia G; Womack, Christopher J; Saunders, Michael J

    2012-07-01

    The effects of different carbohydrate-protein (CHO + Pro) beverages were compared during recovery from cycling exercise. Twelve male cyclists (VO(2peak): 65 ± 7 mL/kg/min) completed ~1 h of high-intensity intervals (EX1). Immediately and 120 min following EX1, subjects consumed one of three calorically-similar beverages (285-300 kcal) in a cross-over design: carbohydrate-only (CHO; 75 g per beverage), high-carbohydrate/low-protein (HCLP; 45 g CHO, 25 g Pro, 0.5 g fat), or low-carbohydrate/high-protein (LCHP; 8 g CHO, 55 g Pro, 4 g fat). After 4 h of recovery, subjects performed subsequent exercise (EX2; 20 min at 70% VO(2peak) + 20 km time-trial). Beverages were also consumed following EX2. Blood glucose levels (30 min after beverage ingestion) differed across all treatments (CHO > HCLP > LCHP; p < 0.05), and serum insulin was higher following CHO and HCLP ingestion versus LCHP. Peak quadriceps force, serum creatine kinase, muscle soreness, and fatigue/energy ratings measured pre- and post-exercise were not different between treatments. EX2 performance was not significantly different between CHO (48.5 ± 1.5 min), HCLP (48.8 ± 2.1 min) and LCHP (50.3 ± 2.7 min). Beverages containing similar caloric content but different proportions of carbohydrate/protein provided similar effects on muscle recovery and subsequent exercise performance in well-trained cyclists. PMID:22852050

  20. Periodic acid-Schiff's reagent assay for carbohydrates in a microtiter plate format.

    PubMed

    Kilcoyne, Michelle; Gerlach, Jared Q; Farrell, Mark P; Bhavanandan, Veer P; Joshi, Lokesh

    2011-09-01

    Microtiter plate colorimetric assays are widely used for analysis of carbohydrates and glycoconjugates. However, mucins are often not easily detected, as they have low neutral sugar content. We have adapted and optimised the periodic acid-Schiff's reagent (PAS) staining for microtiter plate assay by examining five factors: concentration and volume of periodic acid, oxidation time, volume of Schiff's reagent, and color development time. This assay requires just 25 μl of sample, utilises standardised Schiff's reagent, and has decreased assay time (140 min to completion). Seventeen monosaccharides (acidic, neutral, basic, phosphorylated, and deoxy) and four disaccharides were assessed. PAS-positive carbohydrates (amino, N-acetylamino, deoxy, and certain neutral monosaccharides, and sialic acids) responded linearly within a 10-100 nmol range approximately, which varied for each carbohydrate. The assay response for fetuin and porcine gastric mucin (PGM) was linear up to 150 μg (highest concentration tested), with no response from nonglycosylated protein. A lower response for asialofetuin was observed, but desialylated PGM preparations were similar or higher in response than their sialylated counterparts. The simplicity and low sample consumption of this method make it an excellent choice for screening or quantitation of chromatographic fractions containing carbohydrates and glycoconjugates, especially in the case of mucins.

  1. Efficient production of free fatty acids from soybean meal carbohydrates.

    PubMed

    Wang, Dan; Thakker, Chandresh; Liu, Ping; Bennett, George N; San, Ka-Yiu

    2015-11-01

    Conversion of biomass feedstock to chemicals and fuels has attracted increasing attention recently. Soybean meal, containing significant quantities of carbohydrates, is an inexpensive renewable feedstock. Glucose, galactose, and fructose can be obtained by enzymatic hydrolysis of soluble carbohydrates of soybean meal. Free fatty acids (FFAs) are valuable molecules that can be used as precursors for the production of fuels and other value-added chemicals. In this study, free fatty acids were produced by mutant Escherichia coli strains with plasmid pXZ18Z (carrying acyl-ACP thioesterase (TE) and (3R)-hydroxyacyl-ACP dehydratase) using individual sugars, sugar mixtures, and enzymatic hydrolyzed soybean meal extract. For individual sugar fermentations, strain ML211 (MG1655 fadD(-) fabR(-) )/pXZ18Z showed the best performance, which produced 4.22, 3.79, 3.49 g/L free fatty acids on glucose, fructose, and galactose, respectively. While the strain ML211/pXZ18Z performed the best with individual sugars, however, for sugar mixture fermentation, the triple mutant strain XZK211 (MG1655 fadD(-) fabR(-) ptsG(-) )/pXZ18Z with an additional deletion of ptsG encoding the glucose-specific transporter, functioned the best due to relieved catabolite repression. This strain produced approximately 3.18 g/L of fatty acids with a yield of 0.22 g fatty acids/g total sugar. Maximum free fatty acids production of 2.78 g/L with a high yield of 0.21 g/g was achieved using soybean meal extract hydrolysate. The results suggested that soybean meal carbohydrates after enzymatic treatment could serve as an inexpensive feedstock for the efficient production of free fatty acids.

  2. Interactive Effects of Indigestible Carbohydrates, Protein Type, and Protein Level on Biomarkers of Large Intestine Health in Rats.

    PubMed

    Taciak, Marcin; Barszcz, Marcin; Tuśnio, Anna; Pastuszewska, Barbara

    2015-01-01

    The effects of indigestible carbohydrates, protein type, and protein level on large intestine health were examined in rats. For 21 days, 12 groups of six 12-week-old male Wistar rats were fed diets with casein (CAS), or potato protein concentrate (PPC), providing 14% (lower protein level; LP), or 20% (higher protein level; HP) protein, and containing cellulose, resistant potato starch, or pectin. Fermentation end-products, pH, and β-glucuronidase levels in cecal digesta, and ammonia levels in colonic digesta were determined. Cecal digesta, tissue weights, cecal and colon morphology, and colonocyte DNA damage were also analyzed. Digesta pH was lower, whereas relative mass of cecal tissue and digesta were higher in rats fed pectin diets than in those fed cellulose. Cecal parameters were greater in rats fed PPC and HP diets than in those fed CAS and LP diets, respectively. Short-chain fatty acid (SCFA) concentrations were unaffected by protein or carbohydrate type. Total SCFA, acetic acid, and propionic acid concentrations were greater in rats fed LP diets than in those fed HP. Cecal pool of isobutyric and isovaleric acids was greater in rats fed PPC than in those fed CAS diets. PPC diets decreased phenol concentration and increased ammonia concentration in cecal and colonic digesta, respectively. Cecal crypt depth was greater in rats fed PPC and HP diets, and was unaffected by carbohydrates; whereas colonic crypt depth was greater in rats fed cellulose. Myenteron thickness in the cecum was unaffected by nutrition, but was greater in the colon of rats fed cellulose. Colonocyte DNA damage was greater in rats fed LP diets than in those fed HP diets, and was unaffected by carbohydrate or protein type. It was found that nutritional factors decreasing cecal digesta weight contribute to greater phenol production, increased DNA damage, and reduced ammonia concentration in the colon. PMID:26536028

  3. Interactive Effects of Indigestible Carbohydrates, Protein Type, and Protein Level on Biomarkers of Large Intestine Health in Rats

    PubMed Central

    Taciak, Marcin; Barszcz, Marcin; Tuśnio, Anna; Pastuszewska, Barbara

    2015-01-01

    The effects of indigestible carbohydrates, protein type, and protein level on large intestine health were examined in rats. For 21 days, 12 groups of six 12-week-old male Wistar rats were fed diets with casein (CAS), or potato protein concentrate (PPC), providing 14% (lower protein level; LP), or 20% (higher protein level; HP) protein, and containing cellulose, resistant potato starch, or pectin. Fermentation end-products, pH, and β-glucuronidase levels in cecal digesta, and ammonia levels in colonic digesta were determined. Cecal digesta, tissue weights, cecal and colon morphology, and colonocyte DNA damage were also analyzed. Digesta pH was lower, whereas relative mass of cecal tissue and digesta were higher in rats fed pectin diets than in those fed cellulose. Cecal parameters were greater in rats fed PPC and HP diets than in those fed CAS and LP diets, respectively. Short-chain fatty acid (SCFA) concentrations were unaffected by protein or carbohydrate type. Total SCFA, acetic acid, and propionic acid concentrations were greater in rats fed LP diets than in those fed HP. Cecal pool of isobutyric and isovaleric acids was greater in rats fed PPC than in those fed CAS diets. PPC diets decreased phenol concentration and increased ammonia concentration in cecal and colonic digesta, respectively. Cecal crypt depth was greater in rats fed PPC and HP diets, and was unaffected by carbohydrates; whereas colonic crypt depth was greater in rats fed cellulose. Myenteron thickness in the cecum was unaffected by nutrition, but was greater in the colon of rats fed cellulose. Colonocyte DNA damage was greater in rats fed LP diets than in those fed HP diets, and was unaffected by carbohydrate or protein type. It was found that nutritional factors decreasing cecal digesta weight contribute to greater phenol production, increased DNA damage, and reduced ammonia concentration in the colon. PMID:26536028

  4. Amino acid, fatty acid, and carbohydrate content of Artocarpus altilis (breadfruit).

    PubMed

    Golden, K D; Williams, O J

    2001-06-01

    A study is conducted to determine the amino acid, fatty acid, and carbohydrate content of breadfruit using high-performance liquid chromatography (HPLC) and gas chromatography (GC). An HPLC method is used for the determination of amino acids and fatty acids in breadfruit. Representative amino acid samples are derivatized with phenylisothiocianate and the resulting phenylthiocarbamyl derivatives are separated on a reversed-phase column by gradient elution with a 0.05M ammonium acetate buffer and 0.01M ammonium acetate in acetonitrile-methanol-water (44:10:46, v/v). Representative fatty acid samples are derivatized with phenacyl bromide and the resulting fatty acid phenacyl esters are separated on a reversed-phase column by gradient elution with acetonitrile and water. Amino acid and fatty acid derivatives are detected by ultraviolet detection at 254 nm. The analysis of the carbohydrates in breadfruit employs a GC method. Carbohydrates are derivatized using trimethylchlorosilane and hexamethyldisilazane to form trimethylsilyl ethers. Compounds in the samples are separated by the temperature programming of a GC using nitrogen as the carrier gas. Percent recoveries of amino acids, fatty acids, and carbohydrates are 72.5%, 68.2%, and 81.4%, respectively. The starch content of the breadfruit is 15.52 g/100 g fresh weight.

  5. Linkage of carbohydrate to hydroxyamino acids in mucopolysaccharides and mucoproteins

    PubMed Central

    Adams, J. B.

    1965-01-01

    1. Glycosidic linkage of carbohydrate to the primary hydroxyl groups of threonine and serine has been established in human blood-group A and Lea substances, bovine submaxillary-gland mucin and human pseudomyxomatous mucin. 2. Treatment of these substances in 0·09n-lithium hydroxide at 100° for 1hr. led to β-elimination at these glycosidic linkages with the resultant formation of α-oxobutyric acid and glycine from threonine linkages, and pyruvic acid from serine linkages. Though most of the threonine was destroyed in every case, about one-third to one-half of the serine residues resisted alkaline cleavage. Such results, indicative of the presence of unbound serine residues, allow, in submaxillary mucin, for a close correlation between the remaining serine, threonine, glutamic acid and aspartic acid and the available sialyl-(2→6)-N-acetylgalactosamine prosthetic groups. 3. The stoichiometry of the β-eliminations has been demonstrated for pseudomyxomatous mucin. The α-oxo acids were separated and determined as their quinoxalinol derivatives by thin-layer chromatography on silica gel. Reaction at the threonine centres favoured α-oxobutyric acid formation (70%, via the intermediary dehydropeptide) over the alternative pathway to glycine (30%). 4. 100% of the hexosamine was destroyed in submaxillary-gland mucin, 85% in pseudomyxomatous mucin and about 60% in the blood-group substances. In the latter cases, the glucosamine/galactosamine ratio was increased from about 4:1 to 8–10:1, suggesting a preferential destruction of galactosamine. Evidence was obtained, however, for a further destruction of hexosamine, in addition to that which could be theoretically attached to peptide at possible known binding sites. 5. The major part of the alkali-resistant hexosamine in the blood-group substances was non-diffusible and was accompanied by the constituent carbohydrates in similar molar proportions to the native materials. ImagesFig. 1. PMID:16749136

  6. Carbohydrate-protein interactions investigated on plastic chips statically coated with hydrophobically modified hydroxyethylcellulose.

    PubMed

    Dang, Fuquan; Maeda, Eiki; Osafune, Tomo; Nakajima, Kazuki; Kakehi, Kazuaki; Ishikawa, Mitsuru; Baba, Yoshinobu

    2009-12-15

    We developed a novel method for rapid screening of carbohydrate-protein interactions using poly(methyl methacrylate) (PMMA) channels statically coated with hydrophobically modified hydroxyethylcellulose (HM-HEC). We found that a self-assembled monolayer (SAM) of HM-HEC on a PMMA surface intact by water allows rapid and reproducible separations of glycan samples using a 20 mM phosphate without HM-HEC. The underlying mechanism for dynamic and static coatings on the PMMA surface is discussed. Simultaneous analysis of the molecular interaction between a complex mixture of carbohydrates from alpha1-acid glycoprotein and proteins has been successfully achieved in PMMA channels statically coated with a SAM of HM-HEC.

  7. Improved Feed Protein Fractional Schemes for Formulating Rations With the Cornell Net Carbohydrate and Protein System

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Adequate predictions of rumen-degradable protein (RDP) and rumen-undegradable protein (RUP) supplies are necessary to optimize performance while minimizing losses of excess nitrogen (N). The objectives of this study were to evaluate the original Cornell Net Carbohydrate Protein System (CNCPS) protei...

  8. Protein-Carbohydrate Interactions Studied by NMR: From Molecular Recognition to Drug Design

    PubMed Central

    Fernández-Alonso, María del Carmen; Díaz, Dolores; Berbis, Manuel Álvaro; Marcelo, Filipa; Cañada, Javier; Jiménez-Barbero, Jesús

    2012-01-01

    Diseases that result from infection are, in general, a consequence of specific interactions between a pathogenic organism and the cells. The study of host-pathogen interactions has provided insights for the design of drugs with therapeutic properties. One area that has proved to be promising for such studies is the constituted by carbohydrates which participate in biological processes of paramount importance. On the one hand, carbohydrates have shown to be information carriers with similar, if not higher, importance than traditionally considered carriers as amino acids and nucleic acids. On the other hand, the knowledge on molecular recognition of sugars by lectins and other carbohydrate-binding proteins has been employed for the development of new biomedical strategies. Biophysical techniques such as X-Ray crystallography and NMR spectroscopy lead currently the investigation on this field. In this review, a description of traditional and novel NMR methodologies employed in the study of sugar-protein interactions is briefly presented in combination with a palette of NMR-based studies related to biologically and/or pharmaceutically relevant applications. PMID:23305367

  9. Selection of dietary protein and carbohydrate by rats: Changes with maturation

    NASA Technical Reports Server (NTRS)

    Yokogoshi, Hidehiko; Theall, Cynthia L.; Wurtman, Richard J.

    1985-01-01

    Weaning (21-day-old; 40-50 g) male rats given simultaneous access to foods, containing 18 percent casein and 15 or 70 percent carbohydrate (dextrin), tended to consume only 29-35 percent as much protein as carbohydrate (i.e., protein/carbohydrate ratios were 0.29-0.35). With maturation, when animals weighed 100 g or more, about half continued this pattern of nutrient choice, but the others abruptly began to consume considerably larger proportions of protein, exhibiting protein/carbohydrate ratios as high as 0.80-1.00. Each adult animal's protein/carbohydrate ratio tended to vary only slightly (s.e. = 3 percent of means). Adult protein/carbohydrate ratios were not correlated with fasting brain 5-HT or 5-HIAA levels. These marked differences among rats in eating behavior would not be observed when--as is usually the case--animals are given access to only one diet.

  10. Lanthanide-chelating carbohydrate conjugates are useful tools to characterize carbohydrate conformation in solution and sensitive sensors to detect carbohydrate-protein interactions.

    PubMed

    Canales, Ángeles; Mallagaray, Álvaro; Berbís, M Álvaro; Navarro-Vázquez, Armando; Domínguez, Gema; Cañada, F Javier; André, Sabine; Gabius, Hans-Joachim; Pérez-Castells, Javier; Jiménez-Barbero, Jesús

    2014-06-01

    The increasing interest in the functional versatility of glycan epitopes in cellular glycoconjugates calls for developing sensitive methods to define carbohydrate conformation in solution and to characterize protein-carbohydrate interactions. Measurements of pseudocontact shifts in the presence of a paramagnetic cation can provide such information. In this work, the energetically privileged conformation of a disaccharide (lactose as test case) was experimentally inferred by using a synthetic carbohydrate conjugate bearing a lanthanide binding tag. In addition, the binding of lactose to a biomedically relevant receptor (the human adhesion/growth-regulatory lectin galectin-3) and its consequences in structural terms were defined, using Dy(3+), Tb(3+), and Tm(3+). The described approach, complementing the previously tested protein tagging as a way to exploit paramagnetism, enables to detect binding, even weak interactions, and to characterize in detail topological aspects useful for physiological ligands and mimetics in drug design.

  11. Periexercise coingestion of branched-chain amino acids and carbohydrate in men does not preferentially augment resistance exercise-induced increases in phosphatidylinositol 3 kinase/protein kinase B-mammalian target of rapamycin pathway markers indicative of muscle protein synthesis.

    PubMed

    Ferreira, Maria Pontes; Li, Rui; Cooke, Matthew; Kreider, Richard B; Willoughby, Darryn S

    2014-03-01

    The effects of a single bout of resistance exercise (RE) in conjunction with periexercise branched-chain amino acid (BCAA) and carbohydrate (CHO) ingestion on skeletal muscle signaling markers indicative of muscle protein synthesis were determined. It was hypothesized that CHO + BCAA would elicit a more profound effect on these signaling markers compared with CHO. Twenty-seven males were randomly assigned to CHO, CHO + BCAA, or placebo (PLC) groups. Four sets of leg presses and leg extensions were performed at 80% 1 repetition maximum. Supplements were ingested 30 minutes and immediately before and after RE. Venous blood and muscle biopsy samples were obtained immediately before supplement ingestion and 0.5, 2, and 6 hours after RE. Serum insulin and glucose and phosphorylated levels of muscle insulin receptor substrate 1 (IRS-1), protein kinase B, mammalian target of rapamycin, phosphorylated 70S6 kinase, and 4E binding protein 1 were assessed. Data were analyzed by 2-way repeated-measures analysis of variance. Significant group × time interactions were observed for glucose and insulin (P < .05) showing that CHO and CHO + BCAA were significantly greater than PLC. Significant time main effects were observed for IRS-1 (P = .001), protein kinase B (P = .031), mammalian target of rapamycin (P = .003), and phosphorylated 70S6 kinase (P = .001). Carbohydrate and CHO + BCAA supplementation significantly increased IRS-1 compared with PLC (P = .002). However, periexercise coingestion of CHO and BCAA did not augment RE-induced increases in skeletal muscle signaling markers indicative of muscle protein synthesis when compared with CHO.

  12. Carbohydrate metabolism during prolonged exercise and recovery: interactions between pyruvate dehydrogenase, fatty acids, and amino acids.

    PubMed

    Mourtzakis, Marina; Saltin, Bengt; Graham, Terry; Pilegaard, Henriette

    2006-06-01

    During prolonged exercise, carbohydrate oxidation may result from decreased pyruvate production and increased fatty acid supply and ultimately lead to reduced pyruvate dehydrogenase (PDH) activity. Pyruvate also interacts with the amino acids alanine, glutamine, and glutamate, whereby the decline in pyruvate production could affect tricarboxycylic acid cycle flux as well as gluconeogenesis. To enhance our understanding of these interactions, we studied the time course of changes in substrate utilization in six men who cycled at 44+/-1% peak oxygen consumption (mean+/-SE) until exhaustion (exhaustion at 3 h 23 min+/-11 min). Femoral arterial and venous blood, blood flow measurements, and muscle samples were obtained hourly during exercise and recovery (3 h). Carbohydrate oxidation peaked at 30 min of exercise and subsequently decreased for the remainder of the exercise bout (P<0.05). PDH activity peaked at 2 h of exercise, whereas pyruvate production peaked at 1 h of exercise and was reduced (approximately 30%) thereafter, suggesting that pyruvate availability primarily accounted for reduced carbohydrate oxidation. Increased free fatty acid uptake (P<0.05) was also associated with decreasing PDH activity (P<0.05) and increased PDH kinase 4 mRNA (P<0.05) during exercise and recovery. At 1 h of exercise, pyruvate production was greatest and was closely linked to glutamate, which was the predominant amino acid taken up during exercise and recovery. Alanine and glutamine were also associated with pyruvate metabolism, and they comprised approximately 68% of total amino-acid release during exercise and recovery. Thus reduced pyruvate production was primarily associated with reduced carbohydrate oxidation, whereas the greatest production of pyruvate was related to glutamate, glutamine, and alanine metabolism in early exercise. PMID:16424076

  13. Amino acids and proteins.

    PubMed

    van Goudoever, Johannes B; Vlaardingerbroek, Hester; van den Akker, Chris H; de Groof, Femke; van der Schoor, Sophie R D

    2014-01-01

    Amino acids and protein are key factors for growth. The neonatal period requires the highest intake in life to meet the demands. Those demands include amino acids for growth, but proteins and amino acids also function as signalling molecules and function as neurotransmitters. Often the nutritional requirements are not met, resulting in a postnatal growth restriction. However, current knowledge on adequate levels of both amino acid as well as protein intake can avoid under nutrition in the direct postnatal phase, avoid the need for subsequent catch-up growth and improve later outcome.

  14. Intake of Protein Plus Carbohydrate during the First Two Hours after Exhaustive Cycling Improves Performance the following Day

    PubMed Central

    Rustad, Per I.; Kolnes, Kristoffer J.; Sollie, Ove; Franch, Jesper; Ivy, John L.; Daniel, Hannelore; Jensen, Jørgen

    2016-01-01

    Intake of protein immediately after exercise stimulates protein synthesis but improved recovery of performance is not consistently observed. The primary aim of the present study was to compare performance 18 h after exhaustive cycling in a randomized diet-controlled study (175 kJ·kg-1 during 18 h) when subjects were supplemented with protein plus carbohydrate or carbohydrate only in a 2-h window starting immediately after exhaustive cycling. The second aim was to investigate the effect of no nutrition during the first 2 h and low total energy intake (113 kJ·kg-1 during 18 h) on performance when protein intake was similar. Eight endurance-trained subjects cycled at 237±6 Watt (~72% VO2max) until exhaustion (TTE) on three occasions, and supplemented with 1.2 g carbohydrate·kg-1·h-1 (CHO), 0.8 g carbohydrate + 0.4 g protein·kg-1·h-1 (CHO+PRO) or placebo without energy (PLA). Intake of CHO+PROT increased plasma glucose, insulin, and branch chained amino acids, whereas CHO only increased glucose and insulin. Eighteen hours later, subjects performed another TTE at 237±6 Watt. TTE was increased after intake of CHO+PROT compared to CHO (63.5±4.4 vs 49.8±5.4 min; p<0.05). PLA reduced TTE to 42.8±5.1 min (p<0.05 vs CHO). Nitrogen balance was positive in CHO+PROT, and negative in CHO and PLA. In conclusion, performance was higher 18 h after exhaustive cycling with intake of CHO+PROT compared to an isocaloric amount of carbohydrate during the first 2 h post exercise. Intake of a similar amount of protein but less carbohydrate during the 18 h recovery period reduced performance. PMID:27078151

  15. Intake of Protein Plus Carbohydrate during the First Two Hours after Exhaustive Cycling Improves Performance the following Day.

    PubMed

    Rustad, Per I; Sailer, Manuela; Cumming, Kristoffer T; Jeppesen, Per B; Kolnes, Kristoffer J; Sollie, Ove; Franch, Jesper; Ivy, John L; Daniel, Hannelore; Jensen, Jørgen

    2016-01-01

    Intake of protein immediately after exercise stimulates protein synthesis but improved recovery of performance is not consistently observed. The primary aim of the present study was to compare performance 18 h after exhaustive cycling in a randomized diet-controlled study (175 kJ·kg(-1) during 18 h) when subjects were supplemented with protein plus carbohydrate or carbohydrate only in a 2-h window starting immediately after exhaustive cycling. The second aim was to investigate the effect of no nutrition during the first 2 h and low total energy intake (113 kJ·kg(-1) during 18 h) on performance when protein intake was similar. Eight endurance-trained subjects cycled at 237±6 Watt (~72% VO2max) until exhaustion (TTE) on three occasions, and supplemented with 1.2 g carbohydrate·kg(-1)·h(-1) (CHO), 0.8 g carbohydrate + 0.4 g protein·kg(-1)·h(-1) (CHO+PRO) or placebo without energy (PLA). Intake of CHO+PROT increased plasma glucose, insulin, and branch chained amino acids, whereas CHO only increased glucose and insulin. Eighteen hours later, subjects performed another TTE at 237±6 Watt. TTE was increased after intake of CHO+PROT compared to CHO (63.5±4.4 vs 49.8±5.4 min; p<0.05). PLA reduced TTE to 42.8±5.1 min (p<0.05 vs CHO). Nitrogen balance was positive in CHO+PROT, and negative in CHO and PLA. In conclusion, performance was higher 18 h after exhaustive cycling with intake of CHO+PROT compared to an isocaloric amount of carbohydrate during the first 2 h post exercise. Intake of a similar amount of protein but less carbohydrate during the 18 h recovery period reduced performance. PMID:27078151

  16. Intake of Protein Plus Carbohydrate during the First Two Hours after Exhaustive Cycling Improves Performance the following Day.

    PubMed

    Rustad, Per I; Sailer, Manuela; Cumming, Kristoffer T; Jeppesen, Per B; Kolnes, Kristoffer J; Sollie, Ove; Franch, Jesper; Ivy, John L; Daniel, Hannelore; Jensen, Jørgen

    2016-01-01

    Intake of protein immediately after exercise stimulates protein synthesis but improved recovery of performance is not consistently observed. The primary aim of the present study was to compare performance 18 h after exhaustive cycling in a randomized diet-controlled study (175 kJ·kg(-1) during 18 h) when subjects were supplemented with protein plus carbohydrate or carbohydrate only in a 2-h window starting immediately after exhaustive cycling. The second aim was to investigate the effect of no nutrition during the first 2 h and low total energy intake (113 kJ·kg(-1) during 18 h) on performance when protein intake was similar. Eight endurance-trained subjects cycled at 237±6 Watt (~72% VO2max) until exhaustion (TTE) on three occasions, and supplemented with 1.2 g carbohydrate·kg(-1)·h(-1) (CHO), 0.8 g carbohydrate + 0.4 g protein·kg(-1)·h(-1) (CHO+PRO) or placebo without energy (PLA). Intake of CHO+PROT increased plasma glucose, insulin, and branch chained amino acids, whereas CHO only increased glucose and insulin. Eighteen hours later, subjects performed another TTE at 237±6 Watt. TTE was increased after intake of CHO+PROT compared to CHO (63.5±4.4 vs 49.8±5.4 min; p<0.05). PLA reduced TTE to 42.8±5.1 min (p<0.05 vs CHO). Nitrogen balance was positive in CHO+PROT, and negative in CHO and PLA. In conclusion, performance was higher 18 h after exhaustive cycling with intake of CHO+PROT compared to an isocaloric amount of carbohydrate during the first 2 h post exercise. Intake of a similar amount of protein but less carbohydrate during the 18 h recovery period reduced performance.

  17. Breakfast high in whey protein or carbohydrates improves coping with workload in healthy subjects.

    PubMed

    Sihvola, Nora; Korpela, Riitta; Henelius, Andreas; Holm, Anu; Huotilainen, Minna; Müller, Kiti; Poussa, Tuija; Pettersson, Kati; Turpeinen, Anu; Peuhkuri, Katri

    2013-11-14

    Dietary components may affect brain function and influence behaviour by inducing the synthesis of neurotransmitters. The aim of the present study was to examine the influence of consumption of a whey protein-containing breakfast drink v. a carbohydrate drink v. control on subjective and physiological responses to mental workload in simulated work. In a randomised cross-over design, ten healthy subjects (seven women, median age 26 years, median BMI 23 kg/m(2)) participated in a single-blinded, placebo-controlled study. The subjects performed demanding work-like tasks after having a breakfast drink high in protein (HP) or high in carbohydrate (HC) or a control drink on separate sessions. Subjective states were assessed using the NASA Task Load Index (NASA-TLX), the Karolinska sleepiness scale (KSS) and the modified Profile of Mood States. Heart rate was recorded during task performance. The ratio of plasma tryptophan (Trp) to the sum of the other large neutral amino acids (LNAA) and salivary cortisol were also analysed. The plasma Trp:LNAA ratio was 30 % higher after the test drinks HP (median 0·13 (μmol/l)/(μmol/l)) and HC (median 0·13 (μmol/l)/(μmol/l)) than after the control drink (median 0·10 (μmol/l)/(μmol/l)). The increase in heart rate was smaller after the HP (median 2·7 beats/min) and HC (median 1·9 beats/min) drinks when compared with the control drink (median 7·2 beats/min) during task performance. Subjective sleepiness was reduced more after the HC drink (median KSS - 1·5) than after the control drink (median KSS - 0·5). There were no significant differences between the breakfast types in the NASA-TLX index, cortisol levels or task performance. We conclude that a breakfast drink high in whey protein or carbohydrates may improve coping with mental tasks in healthy subjects.

  18. Acid-Catalyzed Algal Biomass Pretreatment for Integrated Lipid and Carbohydrate-Based Biofuels Production

    SciTech Connect

    Laurens, L. M. L.; Nagle, N.; Davis, R.; Sweeney, N.; Van Wychen, S.; Lowell, A.; Pienkos, P. T.

    2014-11-12

    One of the major challenges associated with algal biofuels production in a biorefinery-type setting is improving biomass utilization in its entirety, increasing the process energetic yields and providing economically viable and scalable co-product concepts. We demonstrate the effectiveness of a novel, integrated technology based on moderate temperatures and low pH to convert the carbohydrates in wet algal biomass to soluble sugars for fermentation, while making lipids more accessible for downstream extraction and leaving a protein-enriched fraction behind. We studied the effect of harvest timing on the conversion yields, using two algal strains; Chlorella and Scenedesmus, generating biomass with distinctive compositional ratios of protein, carbohydrate, and lipids. We found that the late harvest Scenedesmus biomass had the maximum theoretical biofuel potential at 143 gasoline gallon equivalent (GGE) combined fuel yield per dry ton biomass, followed by late harvest Chlorella at 128 GGE per ton. Our experimental data show a clear difference between the two strains, as Scenedesmus was more successfully converted in this process with a demonstrated 97 GGE per ton. Our measurements indicated a release of >90% of the available glucose in the hydrolysate liquors and an extraction and recovery of up to 97% of the fatty acids from wet biomass. Techno-economic analysis for the combined product yields indicates that this process exhibits the potential to improve per-gallon fuel costs by up to 33% compared to a lipids-only process for one strain, Scenedesmus, grown to the mid-point harvest condition.

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

    ERIC Educational Resources Information Center

    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…

  20. Steam explosion of Brewer's spent grain improves enzymatic digestibility of carbohydrates and affects solubility and stability of proteins.

    PubMed

    Kemppainen, K; Rommi, K; Holopainen, U; Kruus, K

    2016-09-01

    Steam explosion was studied as a means to improve the enzymatic digestibility of carbohydrates in Brewer's spent grain, a protein and lipid-rich lignocellulosic by-product of the brewing industry. Having temperature, treatment time and the presence of acid catalyst as variables, a treatment at 200 °C for 10 min without an acid catalyst was found to be the most efficient, dissolving 12.1 % of the dry matter. Mainly oligomeric non-cellulosic glucan and arabinoxylan were dissolved, and the remaining insoluble carbohydrates could be efficiently hydrolysed by an enzyme cocktail (75 % hydrolysis yield). The process also caused partial protein degradation and dissolved over a third of the total nitrogen. Meanwhile, the insoluble protein appeared to become more strongly associated with acid-insoluble lignin. Compositional changes observed in the proteins and carbohydrates were supported by the results of epifluorescence microscopy. The process yielded three chemically different fractions which could serve as biorefinery products or intermediates. PMID:27085356

  1. Fractionation of carbohydrate and protein content of some forage feeds of ruminants for nutritive evaluation

    PubMed Central

    Das, Lalatendu Keshary; Kundu, S. S.; Kumar, Dinesh; Datt, Chander

    2015-01-01

    Aim: To evaluate some forage feeds of ruminants in terms of their carbohydrate (CHO) and protein fractions using Cornell Net Carbohydrate and Protein System (CNCPS). Materials and Methods: Eleven ruminant feeds (six green fodders - maize, oat, sorghum, bajra, cowpea, berseem and five range herbages - para grass, guinea grass, hedge lucerne, setaria grass and hybrid napier) were selected for this study. Each feed was chemically analyzed for proximate principles (dry matter, crude protein [CP], ether extract, organic matter and ash), fiber fractions (neutral detergent fiber, acid detergent fiber, acid detergent lignin, cellulose and hemicellulose), primary CHO fractions (CHO, non-structural CHO, structural CHO and starch) and primary protein fractions (neutral detergent insoluble CP, acid detergent insoluble CP, non-protein nitrogen and soluble protein). The results were fitted to the equations of CNCPS to arrive at various CHO (CA - fast degrading, CB1 - intermediate degrading, CB2 - slow degrading and CC - non-degrading or unavailable) and protein (PA - instantaneously degrading, PB1 - fast degrading, PB2 - intermediate degrading, PB3 - slow degrading and PC - non-degrading or unavailable) fractions of test feeds. Results: Among green fodders, cowpea and berseem had higher CA content while except hedge lucerne all range herbages had lower CA values. CB1 content of all feeds was low but similar. All feeds except cowpea, berseem, and hedge lucerne contained higher CB2 values. Oat among green fodders and hybrid napier among range herbages had lower CC fraction. Feeds such as bajra, cowpea, berseem and the setaria grass contained lower PA fraction. All green fodders had higher PB1 content except maize and cowpea while all range herbages had lower PB1 values except hedge lucerne. Para grass and hybrid napier contained exceptionally low PB2 fraction among all feeds. Low PC contents were reported in oat and berseem fodders. Conclusion: Based on our findings, it was

  2. Carbohydrate and amino acid metabolism of Spironucleus vortens.

    PubMed

    Millet, Coralie O M; Lloyd, David; Coogan, Michael P; Rumsey, Joanna; Cable, Joanne

    2011-09-01

    The metabolism of Spironucleus vortens, a parasitic, diplomonad flagellate related to Giardia intestinalis, was investigated using a combination of membrane inlet mass spectrometry, (1)H NMR, (13)C NMR, bioscreen continuous growth monitoring, and ion exchange chromatography. The products of glucose-fuelled and endogenous metabolism were identified by (1)H NMR and (13)C NMR as ethanol, acetate, alanine and lactate. Mass spectrometric monitoring of gas metabolism in buffered cell suspensions showed that glucose and ethanol could be used by S. vortens as energy-generating substrates, but bioscreen automated monitoring of growth in culture medium, as well as NMR analyses, suggested that neither of these compounds are the substrates of choice for this organism. Ion-exchange chromatographic analyses of free amino-acid and amino-acid hydrolysate of growth medium revealed that, despite the availability of large pools of free amino-acids in the medium, S. vortens hydrolysed large amounts of proteins during growth. The organism produced alanine and aspartate, and utilised lysine, arginine, leucine, cysteine and urea. However, mass spectrometric and bioscreen investigations showed that addition of the utilised amino acids to diluted culture medium did not induce any significant increase in metabolic or growth rates. Moreover, as no significant amounts of ornithine were produced, and addition of arginine under aerobic conditions did not generate NO production, there was no evidence of the presence of an energy-generating, arginine dihydrolase pathway in S. vortens under in vitro conditions.

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

    PubMed

    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.

  4. Effects of components of meals (carbohydrate, fat, protein) in causing postprandial exertional angina pectoris.

    PubMed

    Baliga, R R; Burden, L; Sidhu, M K; Rampling, M W; Kooner, J S

    1997-05-15

    We have shown that unlike fat, protein, xylose, or water, the carbohydrate component of the meal accelerates myocardial ischemia, reduces exercise capacity, and is associated with a more rapid increase in the determinants of myocardial oxygen consumption than exercise in the fasting state. Our results suggest a role for a larger increase in sympathetic nervous activity and/or release of vasoactive gastrointestinal peptides after carbohydrate, but not fat or protein, meals in postprandial angina. PMID:9165167

  5. Towards complete hydrolysis of soy flour carbohydrates by enzyme mixtures for protein enrichment: A modeling approach.

    PubMed

    Loman, Abdullah Al; Ju, Lu-Kwang

    2016-05-01

    Soy protein is a well-known nutritional supplement in proteinaceous food and animal feed. However, soybeans contain complex carbohydrate. Selective carbohydrate removal by enzymes could increase the protein content and remove the indigestibility of soy products for inclusion in animal feed. Complete hydrolysis of soy flour carbohydrates is challenging due to the presence of proteins and different types of non-structural polysaccharides. This study is designed to guide complex enzyme mixture required for hydrolysis of all types of soy flour carbohydrates. Enzyme broths from Aspergillus niger, Aspergillus aculeatus and Trichoderma reesei fermentations were evaluated in this study for soy carbohydrate hydrolysis. The resultant hydrolysate was measured for solubilized carbohydrate by both total carbohydrate and reducing sugar analyses. Conversion data attained after 48h hydrolysis were first fitted with models to determine the maximum fractions of carbohydrate hydrolyzable by each enzyme group, i.e., cellulase, xylanase, pectinase and α-galactosidase. Kinetic models were then developed to describe the increasing conversions over time under different enzyme activities and process conditions. The models showed high fidelity in predicting soy carbohydrate hydrolysis over broad ranges of soy flour loading (5-25%) and enzyme activities: per g soy flour, cellulase, 0.04-30 FPU; xylanase, 3.5-618U; pectinase, 0.03-120U; and α-galactosidase, 0.01-60U. The models are valuable in guiding the development and production of optimal enzyme mixtures toward hydrolysis of all types of carbohydrates present in soy flour and in optimizing the design and operation of hydrolysis reactor and process.

  6. Orchestration of carbohydrate processing for crassulacean acid metabolism.

    PubMed

    Borland, Anne M; Guo, Hao-Bo; Yang, Xiaohan; Cushman, John C

    2016-06-01

    The production of phosphoenolpyruvate as a substrate for nocturnal CO2 uptake represents a significant sink for carbohydrate in CAM plants which has to be balanced with the provisioning of carbohydrate for growth and maintenance. In starch-storing CAM species, diversification in chloroplast metabolite transporters, and the deployment of both phosphorolytic and hydrolytic routes of starch degradation accommodate a division of labour in directing C-skeletons towards nocturnal carboxylation or production of sucrose for growth. In soluble-sugar storing CAM plants, the vacuole plays a central role in managing carbon homeostasis. The molecular identities of various types of vacuolar sugar transporters have only been identified for C3 species within the last 10 years. The recent availability of CAM genomes enables the identification of putative orthologues of vacuolar sugar transporters which represent strategic targets for orchestrating the diel provisioning of substrate for nocturnal carboxylation and growth. PMID:27101569

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

    PubMed Central

    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

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

    PubMed

    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.

  9. Metabolism of organic acids, nitrogen and amino acids in chlorotic leaves of 'Honeycrisp' apple (Malus domestica Borkh) with excessive accumulation of carbohydrates.

    PubMed

    Wang, Huicong; Ma, Fangfang; Cheng, Lailiang

    2010-07-01

    Metabolite profiles and activities of key enzymes in the metabolism of organic acids, nitrogen and amino acids were compared between chlorotic leaves and normal leaves of 'Honeycrisp' apple to understand how accumulation of non-structural carbohydrates affects the metabolism of organic acids, nitrogen and amino acids. Excessive accumulation of non-structural carbohydrates and much lower CO(2) assimilation were found in chlorotic leaves than in normal leaves, confirming feedback inhibition of photosynthesis in chlorotic leaves. Dark respiration and activities of several key enzymes in glycolysis and tricarboxylic acid (TCA) cycle, ATP-phosphofructokinase, pyruvate kinase, citrate synthase, aconitase and isocitrate dehydrogenase were significantly higher in chlorotic leaves than in normal leaves. However, concentrations of most organic acids including phosphoenolpyruvate (PEP), pyruvate, oxaloacetate, 2-oxoglutarate, malate and fumarate, and activities of key enzymes involved in the anapleurotic pathway including PEP carboxylase, NAD-malate dehydrogenase and NAD-malic enzyme were significantly lower in chlorotic leaves than in normal leaves. Concentrations of soluble proteins and most free amino acids were significantly lower in chlorotic leaves than in normal leaves. Activities of key enzymes in nitrogen assimilation and amino acid synthesis, including nitrate reductase, glutamine synthetase, ferredoxin and NADH-dependent glutamate synthase, and glutamate pyruvate transaminase were significantly lower in chlorotic leaves than in normal leaves. It was concluded that, in response to excessive accumulation of non-structural carbohydrates, glycolysis and TCA cycle were up-regulated to "consume" the excess carbon available, whereas the anapleurotic pathway, nitrogen assimilation and amino acid synthesis were down-regulated to reduce the overall rate of amino acid and protein synthesis.

  10. Effects of synchronicity of carbohydrate and protein degradation on rumen fermentation characteristics and microbial protein synthesis.

    PubMed

    Seo, J K; Kim, M H; Yang, J Y; Kim, H J; Lee, C H; Kim, K H; Ha, Jong K

    2013-03-01

    A series of in vitro studies were carried out to determine i) the effects of enzyme and formaldehyde treatment on the degradation characteristics of carbohydrate and protein sources and on the synchronicity of these processes, and ii) the effects of synchronizing carbohydrate and protein supply on rumen fermentation and microbial protein synthesis (MPS) in in vitro experiments. Untreated corn (C) and enzyme-treated corn (EC) were combined with soy bean meal with (ES) and without (S) enzyme treatment or formaldehyde treatment (FS). Six experimental feeds (CS, CES, CFS, ECS, ECES and ECFS) with different synchrony indices were prepared. Highly synchronous diets had the greatest dry matter (DM) digestibility when untreated corn was used. However, the degree of synchronicity did not influence DM digestibility when EC was mixed with various soybean meals. At time points of 12 h and 24 h of incubation, EC-containing diets showed lower ammonia-N concentrations than those of C-containing diets, irrespective of the degree of synchronicity, indicating that more efficient utilization of ammonia-N for MPS was achieved by ruminal microorganisms when EC was offered as a carbohydrate source. Within C-containing treatments, the purine base concentration increased as the diets were more synchronized. This effect was not observed when EC was offered. There were significant effects on VFA concentration of both C and S treatments and their interactions. Similar to purine concentrations, total VFA production and individual VFA concentration in the groups containing EC as an energy source was higher than those of other groups (CS, CES and CFS). The results of the present study suggested that the availability of energy or the protein source are the most limiting factors for rumen fermentation and MPS, rather than the degree of synchronicity.

  11. CHARACTERIZATION OF THE CARBOHYDRATE COMPONENTS OF Taenia solium ONCOSPHERE PROTEINS AND THEIR ROLE IN THE ANTIGENICITY

    PubMed Central

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

    2015-01-01

    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 post-translational 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. PMID:23982308

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

    PubMed

    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.

  13. In vitro studies into some parameters of protein and carbohydrate metabolism in lymphocytes infected with bovine leucosis virus.

    PubMed

    Madej, J A; Sobiech, K A; Klimentowski, S

    1989-11-01

    Several parameters of protein and carbohydrate metabolism were determined in normal and leukemic lymphocytes in vitro in cattle, including arylamidase activity toward beta-naphthylamides of L-amino acids. The homogenate of bovine leukemic lymphocytes, in comparison with the control revealed increase of gamma-glutamyltransferase, activity trypsin inhibitor and papain inhibitor concentration and aldolase activity. On the other hand, proteolytic activity toward casein and histomucoid content decreased. Out of the 7 substrates used in the study, only 2, alanyl-beta-naphthylamide and leucyl-beta-naphthylamide, demonstrated lower activity in the leukemic material. Disorders in carbohydrate and protein metabolism in the observed lymphocytes in vitro in cattle are presented in the paper. PMID:2559671

  14. Investigation of phospholipid synthesis and the disposition of amino acid and carbohydrate

    SciTech Connect

    Boehme, D.S.

    1986-01-01

    The synthesis of pulmonary phospholipids by offspring of diabetic female rats was assessed by means of high performance liquid chromatography combined with automated phosphate analysis. No changes in the pool sizes of the major phospholipids or their precursors were observed. However, offspring of both insulin-treated and untreated diabetic mothers displayed increased pulmonary lyso-phosphatidylcholine. The concentration of glycerylphosphorylcholine, the metabolic product of lyso-phosphatidylcholine, was also increased in these offspring, providing further evidence of a reduced reacylation pathway in the offspring of diabetic mothers. The concentration of phosphatidylglycerol was reduced in the lungs from offspring of diabetic mothers. Preliminary investigation suggested that the mechanism of insulin action on lungs from offspring of diabetic rats may be the diversion of substrate from lipid synthetic pathways into protein synthesis. The utilization of (14C)-labeled amino acids and carbohydrates by normal fetal rat lung, however, revealed no direct insulin effect on protein synthesis. The ability of the fetal lung to convert amino acids into Krebs Cycle intermediates was demonstrated.

  15. Nutrient digestibility and evaluation of protein and carbohydrate fractionation of citrus by-products.

    PubMed

    Lashkari, S; Taghizadeh, A

    2013-08-01

    The protein and carbohydrate fractionation and nutrient digestibility of citrus by-products were determined. Ruminal, intestinal and total tract CP disappearance values were measured by a modified three-step (MTSP) method and in vitro CP disappearance method (IVCP). Test feeds were orange pulp (OP), lime pulp (LP), lemon pulp (LEP), grapefruit pulp (GP), sweet lemon pulp (SLP), bitter lemon pulp (BLP), bergamot orange pulp (BP) and tangerine pulp (TP). The rumen undegradable protein (RUP) fractions of the feedstuffs were obtained by ruminal incubation in three cannulated wethers and incubation in protease solution (protease type xiv, Streptomyces griseus). The data were analysed using completely randomized design. There were significant differences between the tested feeds in protein fractions and acid detergent insoluble nitrogen (ADIN; C fraction) was highest in GP (14.56%) (p<0.001). For carbohydrate fraction, the highest C fraction was also observed in GP (2.67%) and in relation to the other citrus pulps (p<0.001). Ruminal CP disappearance was highest in OP (71.89%) (p<0.001). The level of post-ruminal CP disappearance, measured by MTSP, was highest for BP (34.94%) (p<0.001). The highest in vitro dry matter digestibility (IVDMD) was found for TP (80.44%) followed by that estimated for BP (78.38%) (p<0.001). The estimated metabolizable energy (MJ/kg DM) varied from 9.77 for LP to 12.91 for BP. Tangerine pulp had the highest true rumen digestibility (TRD) (p<0.001). According to the results, it could be concluded that citrus by-products have high nutritive value and also, the in vitro techniques can be easily used to determine of the nutritive value of citrus by-products.

  16. Acid-Catalyzed Algal Biomass Pretreatment for Integrated Lipid and Carbohydrate-Based Biofuels Production

    DOE PAGES

    Laurens, L. M. L.; Nagle, N.; Davis, R.; Sweeney, N.; Van Wychen, S.; Lowell, A.; Pienkos, P. T.

    2014-11-12

    One of the major challenges associated with algal biofuels production in a biorefinery-type setting is improving biomass utilization in its entirety, increasing the process energetic yields and providing economically viable and scalable co-product concepts. We demonstrate the effectiveness of a novel, integrated technology based on moderate temperatures and low pH to convert the carbohydrates in wet algal biomass to soluble sugars for fermentation, while making lipids more accessible for downstream extraction and leaving a protein-enriched fraction behind. We studied the effect of harvest timing on the conversion yields, using two algal strains; Chlorella and Scenedesmus, generating biomass with distinctive compositionalmore » ratios of protein, carbohydrate, and lipids. We found that the late harvest Scenedesmus biomass had the maximum theoretical biofuel potential at 143 gasoline gallon equivalent (GGE) combined fuel yield per dry ton biomass, followed by late harvest Chlorella at 128 GGE per ton. Our experimental data show a clear difference between the two strains, as Scenedesmus was more successfully converted in this process with a demonstrated 97 GGE per ton. Our measurements indicated a release of >90% of the available glucose in the hydrolysate liquors and an extraction and recovery of up to 97% of the fatty acids from wet biomass. Techno-economic analysis for the combined product yields indicates that this process exhibits the potential to improve per-gallon fuel costs by up to 33% compared to a lipids-only process for one strain, Scenedesmus, grown to the mid-point harvest condition.« less

  17. Nutritional evaluation of young bulls on tropical pasture receiving supplements with different protein:carbohydrate ratios.

    PubMed

    Valente, E E L; Paulino, M F; Barros, L V; Almeida, D M; Martins, L S; Cabral, C H A

    2014-10-01

    The objective of this work was to evaluate the nutritional parameters of young bulls supplemented with different ratios of protein: carbohydrate on tropical pastures from 4 until 18 months old. Fifty-five non-castrated beef calves (138.3±3.4 kg, 90 to 150 d of age) were used. The calves (young bulls) were subjected to a 430-d experimental period encompassing 4 seasons. The treatments were as follows: control, only mineral mixture; HPHC, high protein and high carbohydrate supplement; HPLC, high protein and low carbohydrate supplement; LPHC, low protein and high carbohydrate supplement; and LPLC, low protein and low carbohydrate supplement. The amount of supplement was adjusted every 28 d. Dry matter (DM) intake was higher in the dry-to-rainy transition and rainy seasons for all nutritional plans. Non-supplemented animals had lower intakes of DM and total digestible nutrients (TDN) than supplemented young bulls in all seasons. Although differences in DM intake were not observed between supplemented animals, the supplements with high carbohydrate (HPHC and LPHC) had lower forage intake during suckling (rainy-to-dry transition season) and in the rainy season. However, the HPHC treatment animals had higher intake and digestibility of neutral detergent fiber. It can be concluded that supplementation with high protein levels (supplying 50% of the crude protein requirement) provide the best nutritional parameters for grazing young bulls in most seasons, increasing intake and digestibility of diet, and these effects are more intense when associated with high carbohydrate levels level (supplying 30% TDN requirement).

  18. Disorders of Carbohydrate Metabolism

    MedlinePlus

    ... Metabolic Disorders Disorders of Carbohydrate Metabolism Disorders of Amino Acid Metabolism Disorders of Lipid Metabolism Carbohydrates are sugars. ... Metabolic Disorders Disorders of Carbohydrate Metabolism Disorders of Amino Acid Metabolism Disorders of Lipid Metabolism NOTE: This is ...

  19. Comparison of low fat and low carbohydrate diets on circulating fatty acid composition and markers of inflammation.

    PubMed

    Forsythe, Cassandra E; Phinney, Stephen D; Fernandez, Maria Luz; Quann, Erin E; Wood, Richard J; Bibus, Doug M; Kraemer, William J; Feinman, Richard D; Volek, Jeff S

    2008-01-01

    Abnormal distribution of plasma fatty acids and increased inflammation are prominent features of metabolic syndrome. We tested whether these components of metabolic syndrome, like dyslipidemia and glycemia, are responsive to carbohydrate restriction. Overweight men and women with atherogenic dyslipidemia consumed ad libitum diets very low in carbohydrate (VLCKD) (1504 kcal:%CHO:fat:protein = 12:59:28) or low in fat (LFD) (1478 kcal:%CHO:fat:protein = 56:24:20) for 12 weeks. In comparison to the LFD, the VLCKD resulted in an increased proportion of serum total n-6 PUFA, mainly attributed to a marked increase in arachidonate (20:4n-6), while its biosynthetic metabolic intermediates were decreased. The n-6/n-3 and arachidonic/eicosapentaenoic acid ratio also increased sharply. Total saturated fatty acids and 16:1n-7 were consistently decreased following the VLCKD. Both diets significantly decreased the concentration of several serum inflammatory markers, but there was an overall greater anti-inflammatory effect associated with the VLCKD, as evidenced by greater decreases in TNF-alpha, IL-6, IL-8, MCP-1, E-selectin, I-CAM, and PAI-1. Increased 20:4n-6 and the ratios of 20:4n-6/20:5n-3 and n-6/n-3 are commonly viewed as pro-inflammatory, but unexpectedly were consistently inversely associated with responses in inflammatory proteins. In summary, a very low carbohydrate diet resulted in profound alterations in fatty acid composition and reduced inflammation compared to a low fat diet.

  20. The oligodendrocyte-myelin glycoprotein belongs to a distinct family of proteins and contains the HNK-1 carbohydrate

    PubMed Central

    1990-01-01

    The complete primary structure of the human oligodendrocyte-myelin glycoprotein (OMgp), a glycophospholipid-linked membrane protein of oligodendrocytes and central nervous system myelin, has been determined. The deduced amino acid sequence predicts a polypeptide of 433 amino acids which includes a 17-amino acid leader sequence. OMgp consists of four domains: (a) a short cysteine-rich motif at the NH2 terminus; (b) a series of tandem leucine-rich repeats (LRs) present in several other proteins where they may play roles in adhesion; (c) a serine/threonine-rich region that contains probable attachment sites for O-linked carbohydrates; and (d) a hydrophobic COOH-terminal segment that is likely to be cleaved concomitant with the attachment of lipid during biosynthesis of OMgp. OMgp shares the first three of its four domains with the platelet glycoprotein Ib, which is responsible for the initial adhesion of platelets to the exposed subendothelium during hemostasis. Together with glycoprotein Ib and several other proteins, OMgp belongs to a family of proteins that contain both an NH2-terminal cysteine-rich motif and an adjacent series of LRs. In addition, we report that a subpopulation of OMgp molecules contains the HNK-1 carbohydrate, which has been shown to mediate interactions among cells in the central nervous system. PMID:1688857

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

    NASA Astrophysics Data System (ADS)

    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.

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

    PubMed

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

    2014-08-14

    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.

  3. Substrate Interaction in Intravenous Feeding. Comparative Effects of Carbohydrate and Fat on Amino Acid Utilization in Fasting Man

    PubMed Central

    Wolfe, Bruce M.; Culebras, J. M.; Sim, A. J. W.; Ball, M. R.; Moore, F. D.

    1977-01-01

    emulsion was more effective than the available glycerol alone. The accompanying endocrine and biochemical changes suggest that the milieu for ideal utilization of infused amino acids is variable: ketones at low range (carbohydrate) or moderately elevated (fat emulsion); insulin elevated (carbohydrate) or unchanged (fat emulsion). The utilization of the infused amino acids was markedly improved in both endocrine settings, suggesting that it is the provision of energy as substrate as well as the endocrine setting that determines amino acid utilization. There were other changes in plasma intermediates, particularly fatty acids, glucose and urea, all consistent with the concept that when amino acids are given without other substrates, the amino acids must be maximally utilized for gluconeogenesis. When other substrates are provided (particularly glucose at high dose) then this mandate no longer exists and protein synthesis from the amino acids is favored. Several of the plasma amino acid concentrations responded to glucose when added to amino acid infusion. Amino acids alone produced increases in concentration of all the amino acids found in the infusion with the exception of alanine, arginine, and threonine. Many of these increases were abated by the addition of glucose to the amino acid infusion, suggesting an increased utilization rate. Glycerol and fat emulsion, while modulating increases in the plasma amino acid concentration, did so to a lesser extent than did glucose. This lowering of amino acid concentration was unaccompanied by an increase in urinary excretion. The assumption is therefore made that the provision of the added glucose favors the incorporation of amino acid into protein. There is no evidence from these data to suggest that a rising concentration of ketones in the blood favors amino acid utilization or protein synthesis. PMID:410376

  4. Is carbohydrate needed to further stimulate muscle protein synthesis/hypertrophy following resistance exercise?

    PubMed Central

    2013-01-01

    It is now well established that protein supplementation after resistance exercise promotes increased muscle protein synthesis, which ultimately results in greater net muscle accretion, relative to exercise alone or exercise with supplementary carbohydrate ingestion. However, it is not known whether combining carbohydrate with protein produces a greater anabolic response than protein alone. Recent recommendations have been made that the composition of the ideal supplement post-exercise would be a combination of a protein source with a high glycemic index carbohydrate. This is based on the hypothesis that insulin promotes protein synthesis, thus maximising insulin secretion will maximally potentiate this action. However, it is still controversial as to whether raising insulin level, within the physiological range, has any effect to further stimulate muscle protein synthesis. The present commentary will review the evidence underpinning the recommendation to consume carbohydrates in addition to a protein supplementation after resistance exercise for the specific purpose of increasing muscle mass. The paucity of data will be discussed, thus our conclusions are that further studies are necessary prior to any conclusions that enable evidence-based recommendations to be made. PMID:24066806

  5. Is carbohydrate needed to further stimulate muscle protein synthesis/hypertrophy following resistance exercise?

    PubMed

    Figueiredo, Vandré Casagrande; Cameron-Smith, David

    2013-01-01

    It is now well established that protein supplementation after resistance exercise promotes increased muscle protein synthesis, which ultimately results in greater net muscle accretion, relative to exercise alone or exercise with supplementary carbohydrate ingestion. However, it is not known whether combining carbohydrate with protein produces a greater anabolic response than protein alone. Recent recommendations have been made that the composition of the ideal supplement post-exercise would be a combination of a protein source with a high glycemic index carbohydrate. This is based on the hypothesis that insulin promotes protein synthesis, thus maximising insulin secretion will maximally potentiate this action. However, it is still controversial as to whether raising insulin level, within the physiological range, has any effect to further stimulate muscle protein synthesis. The present commentary will review the evidence underpinning the recommendation to consume carbohydrates in addition to a protein supplementation after resistance exercise for the specific purpose of increasing muscle mass. The paucity of data will be discussed, thus our conclusions are that further studies are necessary prior to any conclusions that enable evidence-based recommendations to be made.

  6. The impact of carbohydrate and protein level and sources on swine manure foaming properties

    Technology Transfer Automated Retrieval System (TEKTRAN)

    This study explored the impact of swine diet on the composition, methane production potential, and foaming properties of manure. Samples of swine manure were collected from controlled feeding trials with diets varying in protein and carbohydrate levels and sources. Protein sources consisted of corn ...

  7. Nutritional balance of essential amino acids and carbohydrates of the adult worker honeybee depends on age.

    PubMed

    Paoli, Pier P; Donley, Dion; Stabler, Daniel; Saseendranath, Anumodh; Nicolson, Susan W; Simpson, Stephen J; Wright, Geraldine A

    2014-06-01

    Dietary sources of essential amino acids (EAAs) are used for growth, somatic maintenance and reproduction. Eusocial insect workers such as honeybees are sterile, and unlike other animals, their nutritional needs should be largely dictated by somatic demands that arise from their role within the colony. Here, we investigated the extent to which the dietary requirements of adult worker honeybees for EAAs and carbohydrates are affected by behavioural caste using the Geometric Framework for nutrition. The nutritional optimum, or intake target (IT), was determined by confining cohorts of 20 young bees or foragers to liquid diets composed of specific proportions of EAAs and sucrose. The IT of young, queenless bees shifted from a proportion of EAAs-to-carbohydrates (EAA:C) of 1:50 towards 1:75 over a 2-week period, accompanied by a reduced lifespan on diets high in EAAs. Foragers required a diet high in carbohydrates (1:250) and also had low survival on diets high in EAA. Workers exposed to queen mandibular pheromone lived longer on diets high in EAA, even when those diets contained 5× their dietary requirements. Our data show that worker honeybees prioritize their intake of carbohydrates over dietary EAAs, even when overeating EAAs to obtain sufficient carbohydrates results in a shorter lifespan. Thus, our data demonstrate that even when young bees are not nursing brood and foragers are not flying, their nutritional needs shift towards a diet largely composed of carbohydrates when they make the transition from within-hive duties to foraging.

  8. Effects of protein and carbohydrate on an insect herbivore: the vista from a fitness landscape.

    PubMed

    Le Gall, Marion; Behmer, Spencer T

    2014-11-01

    Protein and carbohydrates are important nutrients driving the growth of herbivores; however, their content in plants is highly variable. Multiple studies have explored their effect on herbivores, but only one other study (using a caterpillar) has provided a comprehensive overview that includes a simultaneous evaluation of their ratios and concentrations. In the present work, we ran two experiments using nymphs of the generalist grasshopper Melanoplus differentialis. Grasshoppers and caterpillars differ in a number of important ways, which might affect their feeding and physiological responses to foods with variable content of protein and carbohydrates. First, in a choice experiment, we measured performance and related this to the self-selected intake of nutrients. No differences were found for duration of development across treatments, but gain in mass was lower on a diet of low macronutrient concentration. Consumption of protein was always tightly regulated, but intake of carbohydrate was significantly reduced when consuming diluted food. In the second experiment, insects were constrained to one of nine diets and we plotted performance and consumption using a fitness-landscape approach that mimics the natural variation of nutrients in plants. We found significant effects of protein and carbohydrate content on gain in mass and in duration of development. The concentration of macronutrients in the food had more pronounced effects than did the protein-to-carbohydrate ratio. The protein-carbohydrate content also significantly affected the intake of food and energy (calories), production of frass, and digestive efficiency. On foods with low macronutrient concentration consumption was high, but digestive efficiency was low. Our results suggest that insects will favor protein-biased foods when the total macronutrient content of available foods is low, and that in the short-term compensatory feeding responses can overcome nutritional deficits and/or imbalances. However

  9. Effects of protein and carbohydrate on an insect herbivore: the vista from a fitness landscape.

    PubMed

    Le Gall, Marion; Behmer, Spencer T

    2014-11-01

    Protein and carbohydrates are important nutrients driving the growth of herbivores; however, their content in plants is highly variable. Multiple studies have explored their effect on herbivores, but only one other study (using a caterpillar) has provided a comprehensive overview that includes a simultaneous evaluation of their ratios and concentrations. In the present work, we ran two experiments using nymphs of the generalist grasshopper Melanoplus differentialis. Grasshoppers and caterpillars differ in a number of important ways, which might affect their feeding and physiological responses to foods with variable content of protein and carbohydrates. First, in a choice experiment, we measured performance and related this to the self-selected intake of nutrients. No differences were found for duration of development across treatments, but gain in mass was lower on a diet of low macronutrient concentration. Consumption of protein was always tightly regulated, but intake of carbohydrate was significantly reduced when consuming diluted food. In the second experiment, insects were constrained to one of nine diets and we plotted performance and consumption using a fitness-landscape approach that mimics the natural variation of nutrients in plants. We found significant effects of protein and carbohydrate content on gain in mass and in duration of development. The concentration of macronutrients in the food had more pronounced effects than did the protein-to-carbohydrate ratio. The protein-carbohydrate content also significantly affected the intake of food and energy (calories), production of frass, and digestive efficiency. On foods with low macronutrient concentration consumption was high, but digestive efficiency was low. Our results suggest that insects will favor protein-biased foods when the total macronutrient content of available foods is low, and that in the short-term compensatory feeding responses can overcome nutritional deficits and/or imbalances. However

  10. Surface plasmon resonance imaging analysis of protein binding to a sialoside-based carbohydrate microarray.

    PubMed

    Linman, Matthew J; Yu, Hai; Chen, Xi; Cheng, Quan

    2012-01-01

    Monitoring multiple biological interactions in a multiplexed array format has numerous advantages. However, converting well-developed surface chemistry for spectroscopic measurements to array-based, high-throughput screening is not a trivial process and often proves to be the bottleneck in method development. This chapter reports the fabrication and characterization of a new carbohydrate microarray with synthetic sialosides for surface plasmon resonance imaging analysis of lectin-carbohydrate interactions. Contact printing of functional sialosides on neutravidin-coated surfaces was carried out and the properties of the resulting elements were characterized by fluorescence microscopy. Sambucus nigra agglutinin (SNA) was used for testing on four different carbohydrate-functionalized surfaces and differential binding was analyzed. Multiplexed detection of SNA/biotinylated sialoside interactions on arrays up to 400 elements has been performed with good data correlation, demonstrating the effectiveness of the biotin-neutravidin-based biointerface to control probe orientation for reproducible and efficient protein binding to carbohydrates.

  11. 3-Aminoquinoline/p-coumaric acid as a MALDI matrix for glycopeptides, carbohydrates, and phosphopeptides.

    PubMed

    Fukuyama, Yuko; Funakoshi, Natsumi; Takeyama, Kohei; Hioki, Yusaku; Nishikaze, Takashi; Kaneshiro, Kaoru; Kawabata, Shin-Ichirou; Iwamoto, Shinichi; Tanaka, Koichi

    2014-02-18

    Glycosylation and phosphorylation are important post-translational modifications in biological processes and biomarker research. The difficulty in analyzing these modifications is mainly their low abundance and dissociation of labile regions such as sialic acids or phosphate groups. One solution in matrix-assisted laser desorption/ionization (MALDI) mass spectrometry is to improve matrices for glycopeptides, carbohydrates, and phosphopeptides by increasing the sensitivity and suppressing dissociation of the labile regions. Recently, a liquid matrix 3-aminoquinoline (3-AQ)/α-cyano-4-hydroxycinnamic acid (CHCA) (3-AQ/CHCA), introduced by Kolli et al. in 1996, has been reported to increase sensitivity for carbohydrates or phosphopeptides, but it has not been systematically evaluated for glycopeptides. In addition, 3-AQ/CHCA enhances the dissociation of labile regions. In contrast, a liquid matrix 1,1,3,3-tetramethylguanidium (TMG, G) salt of p-coumaric acid (CA) (G3CA) was reported to suppress dissociation of sulfate groups or sialic acids of carbohydrates. Here we introduce a liquid matrix 3-AQ/CA for glycopeptides, carbohydrates, and phosphopeptides. All of the analytes were detected as [M + H](+) or [M - H](-) with higher or comparable sensitivity using 3-AQ/CA compared with 3-AQ/CHCA or 2,5-dihydroxybenzoic acid (2,5-DHB). The sensitivity was increased 1- to 1000-fold using 3-AQ/CA. The dissociation of labile regions such as sialic acids or phosphate groups and the fragmentation of neutral carbohydrates were suppressed more using 3-AQ/CA than using 3-AQ/CHCA or 2,5-DHB. 3-AQ/CA was thus determined to be an effective MALDI matrix for high sensitivity and the suppression of dissociation of labile regions in glycosylation and phosphorylation analyses.

  12. Metabolic responses to dietary protein/carbohydrate ratios in zebra sea bream (Diplodus cervinus, Lowe, 1838) juveniles.

    PubMed

    Coutinho, Filipe; Peres, Helena; Castro, Carolina; Pérez-Jiménez, Amalia; Pousão-Ferreira, Pedro; Oliva-Teles, Aires; Enes, Paula

    2016-02-01

    This study aims to evaluate the effect of diets with different protein to carbohydrate ratios (P:C) on the omnivorous zebra sea bream (Diplodus cervinus) juveniles growth performance, feed efficiency, N excretion and metabolic response of intermediary metabolism enzymes. Four isoenergetic and isolipidic diets were formulated to contain increasing protein levels (25, 35, 45 and 55%) at the expense of carbohydrates (43, 32, 21 and 9%): diets P25C43, P35C32, P45C21 and P55C9. Growth performance, feed efficiency (FE), N intake [(g kg(-1) average body weight (ABW) day(-1))], N retention (g kg(-1) ABW day(-1)) and energy retention (kJ kg(-1) ABW day(-1)) increased with the increase of P:C ratio. The best growth performance and FE were achieved with diet P45C21. Ammonia excretion (mg NH4–N kg(-1) ABW day(-1)) increased as dietary protein level increased. Alanine aminotransferase and glutamate dehydrogenase activities increased with the increase of dietary P:C ratio. The opposite was observed for malic enzyme activity. Aspartate aminotransferase, hexokinase, glucokinase, fructose-1, 6-bisphosphatase and fatty acid synthetase activities were unaffected by dietary treatments. Response of key amino acid catabolic enzymes and N excretion levels to dietary P:C ratio supports the metabolic adaptability of this species to dietary protein inclusion levels. Overall, zebra sea bream seems capable of better utilize dietary protein rather than dietary carbohydrates as energy source which may be an obstacle for using more economically diets and thus for reducing environmental N loads in semi-intensive aquaculture of this species. PMID:26480835

  13. Satiating effects of protein but not carbohydrate consumed in a between-meal beverage context.

    PubMed

    Bertenshaw, Emma J; Lluch, Anne; Yeomans, Martin R

    2008-02-27

    Previous research has suggested that protein is the most satiating macronutrient; however some experiments have found no difference in satiating efficiency of protein and carbohydrate during short intervals after consumption. There is also evidence that the satiating effects of carbohydrate are minimal when in a beverage rather than solid context. To evaluate whether protein-based satiety was evident in a drink context, and clarify further effects of preload time on satiety, the present study compared iso-energetic dairy fruit drink preloads ( approximately 1250 kJ), differing in macronutrient composition and consumed at two time intervals in the morning. Using a counterbalanced within-subjects design, 18 unrestrained lean male volunteers consumed 300 ml of carbohydrate-enriched (CHO), protein-enriched and low-energy control (327 kJ) dairy fruit drinks, 120 min and 30 min before an ad libitum lunch. Significantly less energy was consumed at lunch after the protein (3234 kJ) compared to the control (3468 kJ, p<0.05) and CHO preloads (3588 kJ, p<0.05). However, this was not sufficient to show complete energy compensation. Preload time of consumption did not impact upon any measures. Only satiety ratings at the beginning of lunch varied significantly by preload type, reflecting differences in test meal intake. These findings are consistent with previous research that protein is more satiating than carbohydrate. The roles of sensory and hedonic characteristics are discussed. PMID:17988696

  14. Detailed insights from microarray and crystallographic studies into carbohydrate recognition by microneme protein 1 (MIC1) of Toxoplasma gondii

    PubMed Central

    Garnett, James A; Liu, Yan; Leon, Ester; Allman, Sarah A; Friedrich, Nikolas; Saouros, Savvas; Curry, Stephen; Soldati-Favre, Dominique; Davis, Benjamin G; Feizi, Ten; Matthews, Stephen

    2009-01-01

    The intracellular protozoan Toxoplasma gondii is among the most widespread parasites. The broad host cell range of the parasite can be explained by carbohydrate microarray screening analyses that have demonstrated the ability of the T. gondii adhesive protein, TgMIC1, to bind to a wide spectrum of sialyl oligosaccharide ligands. Here, we investigate by further microarray analyses in a dose-response format the differential binding of TgMIC1 to 2-3- and 2-6-linked sialyl carbohydrates. Interestingly, two novel synthetic fluorinated analogs of 3′SiaLacNAc1–4 and 3′SiaLacNAc1–3 were identified as highly potent ligands. To understand the structural basis of the carbohydrate binding specificity of TgMIC1, we have determined the crystal structures of TgMIC1 micronemal adhesive repeat (MAR)-region (TgMIC1-MARR) in complex with five sialyl-N-acetyllactosamine analogs. These crystal structures have revealed a specific, water-mediated hydrogen bond network that accounts for the preferential binding of TgMIC1-MARR to arrayed 2-3-linked sialyl oligosaccharides and the high potency of the fluorinated analogs. Furthermore, we provide strong evidence for the first observation of a C—F···H—O hydrogen bond within a lectin-carbohydrate complex. Finally, detailed comparison with other oligosaccharide-protein complexes in the Protein Data Bank (PDB) reveals a new family of sialic-acid binding sites from lectins in parasites, bacteria, and viruses. PMID:19593815

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

    SciTech Connect

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

    2009-11-06

    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{sub 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.

  16. Carbohydrate, Organic Acid, and Amino Acid Composition of Bacteroids and Cytosol from Soybean Nodules 1

    PubMed Central

    Streeter, John G.

    1987-01-01

    Metabolites in Bradyrhizobium japonicum bacteroids and in Glycine max (L.) Merr. cytosol from root nodules were analyzed using an isolation technique which makes it possible to estimate and correct for changes in concentration which may occur during bacteroid isolation. Bacteroid and cytosol extracts were fractionated on ion-exchange columns and were analyzed for carbohydrate composition using gas-liquid chromatography and for organic acid and amino acid composition using high performance liquid chromatography. Analysis of organic acids in plant tissues as the phenacyl derivatives is reported for the first time and this approach revealed the presence of several unknown organic acids in nodules. The time required for separation of bacteroids and cytosol was varied, and significant change in concentration of individual compounds during the separation of the two fractions was estimated by calculating the regression of concentration on time. When a statistically significant slope was found, the true concentration was estimated by extrapolating the regression line to time zero. Of 78 concentration estimates made, there was a statistically significant (5% level) change in concentration during sample preparation for only five metabolites: glucose, sucrose, and succinate in the cytosol and d-pinitol and serine in bacteroids. On a mass basis, the major compounds in bacteroids were (descending order of concentration): myo-inositol, d-chiro-inositol, α,α-trehalose, sucrose, aspartate, glutamate, d-pinitol, arginine, malonate, and glucose. On a proportional basis (concentration in bacteroid as percent of concentration in bacteroid + cytosol fractions), the major compounds were: α-aminoadipate (94), trehalose (66), lysine (58), and arginine (46). The results indicate that metabolite concentrations in bacteroids can be reliably determined. PMID:16665774

  17. Formic acid production from carbohydrates biomass by hydrothermal reaction

    NASA Astrophysics Data System (ADS)

    Yun, J.; Jin, F.; Kishita, A.; Tohji, K.; Enomoto, H.

    2010-03-01

    The formation of formic acid or formate salts by hydrothermal oxidation of model biomass materials (glucose, starch and cellulose) was investigated. All experiments were conducted in a batch reactor, made of SUS 316 tubing, providing an internal volume of 5.7 cm3. A 30 wt% hydrogen peroxide aqueous solution was used as an oxidant. The experiments were carried out with temperature of 250°C, reaction time varying from 0.5 min to 5 min, H2O2 supply of 240%, and alkaline concentration varying from 0 to 1.25 M. Similar to glucose, in the cases of the oxidation of hydrothermal starch and cellulose, the addition of alkaline can also improve the yield of formic acid. And the yield were glucose>starch> cellulose in cases of with or without of alkaline addition.

  18. Recovery from a cycling time trial is enhanced with carbohydrate-protein supplementation vs. isoenergetic carbohydrate supplementation

    PubMed Central

    Berardi, John M; Noreen, Eric E; Lemon, Peter WR

    2008-01-01

    Background In this study we assessed whether a liquid carbohydrate-protein (C+P) supplement (0.8 g/kg C; 0.4 g/kg P) ingested early during recovery from a cycling time trial could enhance a subsequent 60 min effort on the same day vs. an isoenergetic liquid carbohydrate (CHO) supplement (1.2 g/kg). Methods Two hours after a standardized breakfast, 15 trained male cyclists completed a time trial in which they cycled as far as they could in 60 min (AMex) using a Computrainer indoor trainer. Following AMex, subjects ingested either C+P, or CHO at 10, 60 and 120 min, followed by a standardized meal at 4 h post exercise. At 6 h post AMex subjects repeated the time trial (PMex). Results There was a significant reduction in performance for both groups in PMex versus AMex. However, performance and power decreases between PMex and AMex were significantly greater (p ≤ 0.05) with CHO (-1.05 ± 0.44 km and -16.50 ± 6.74 W) vs C+P (-0.30 ± 0.50 km and -3.86 ± 6.47 W). Fat oxidation estimated from RER values was significantly greater (p ≤ 0.05) in the C+P vs CHO during the PMex, despite a higher average workload in the C+P group. Conclusion Under these experimental conditions, liquid C+P ingestion immediately after exercise increases fat oxidation, increases recovery, and improves subsequent same day, 60 min efforts relative to isoenergetic CHO ingestion. PMID:19108717

  19. Enhancing flora balance in the gastrointestinal tract of mice by lactic acid bacteria from Chinese sourdough and enzyme activities indicative of metabolism of protein, fat, and carbohydrate by the flora.

    PubMed

    Yang, Dong; Yu, Xiaomin; Wu, Yaoping; Chen, Xingxing; Wei, Hua; Shah, Nagendra P; Xu, Feng

    2016-10-01

    In this study, we investigated the effect of administration of 5 strains of lactic acid bacteria (LAB) isolated from traditional Chinese sourdough on the flora balance of gastrointestinal tract of mice. We specifically measured Enterococcus, Enterobacter, Bacteroides, and Lactobacillus by plate count and real-time PCR methods, and α-glucosidase, lactate dehydrogenase, esterase, and aminopeptidase activities as indicative of metabolism of sugar, fat, and protein from LAB isolated from feces of mice in vitro. The results showed that administration of Lactobacillus acidophilus LAC0201 and Lactobacillus fermentum LFE0302 lowered the uricacid index of serum. Lactobacillus acidophilus LAC0201, L. fermentum LFE0302, as well as Lactobacillus curvatus LCU0401 administration resulted in a reduction in the opportunistic pathogens (i.e., Enterococcus and Enterobacter), meanwhile, administration of L. fermentum LFE0302 and Lactobacillus sp. ULA0104 resulted in an increase in the counts of Lactobacillus. Lactobacillus fermentum LFE0302 administration increased starch digestion of intestinal flora after 4wk of feeding and also resulted in increased α-glucosidase activity in the intestinal flora after 3wk of feeding. We found a similar trend in esterase activity after administration of L. acidophilus LAC0201 for 3wk. Hence, our study suggested that LAB from Chinese sourdough might be used as potential probiotics to strengthen the flora balance in gastrointestinal tract and positively change the metabolism of nutrients through bacterial enzyme activities. PMID:27448855

  20. Pretreatment of Sugar Beet Pulp with Dilute Sulfurous Acid is Effective for Multipurpose Usage of Carbohydrates.

    PubMed

    Kharina, M; Emelyanov, V; Mokshina, N; Ibragimova, N; Gorshkova, T

    2016-05-01

    Sulfurous acid was used for pretreatment of sugar beet pulp (SBP) in order to achieve high efficiency of both extraction of carbohydrates and subsequent enzymatic hydrolysis of the remaining solids. The main advantage of sulfurous acid usage as pretreatment agent is the possibility of its regeneration. Application of sulfurous acid as hydrolyzing agent in relatively low concentrations (0.6-1.0 %) during a short period of time (10-20 min) and low solid to liquid ratio (1:3, 1:6) allowed effective extraction of carbohydrates from SBP and provided positive effect on subsequent enzymatic hydrolysis. The highest obtained concentration of reducing substances (RS) in hydrolysates was 8.5 %; up to 33.6 % of all carbohydrates present in SBP could be extracted. The major obtained monosaccharides were arabinose and glucose (9.4 and 7.3 g/l, respectively). Pretreatment of SBP with sulfurous acid increased 4.6 times the yield of glucose during subsequent enzymatic hydrolysis of remaining solids with cellulase cocktail, as compared to the untreated SBP. Total yield of glucose during SBP pretreatment and subsequent enzymatic hydrolysis amounted to 89.4 % of the theoretical yield. The approach can be applied directly to the wet SBP. Hydrolysis of sugar beet pulp with sulfurous acid is recommended for obtaining of individual monosaccharides, as well as nutritional media. PMID:26821256

  1. Pretreatment of Sugar Beet Pulp with Dilute Sulfurous Acid is Effective for Multipurpose Usage of Carbohydrates.

    PubMed

    Kharina, M; Emelyanov, V; Mokshina, N; Ibragimova, N; Gorshkova, T

    2016-05-01

    Sulfurous acid was used for pretreatment of sugar beet pulp (SBP) in order to achieve high efficiency of both extraction of carbohydrates and subsequent enzymatic hydrolysis of the remaining solids. The main advantage of sulfurous acid usage as pretreatment agent is the possibility of its regeneration. Application of sulfurous acid as hydrolyzing agent in relatively low concentrations (0.6-1.0 %) during a short period of time (10-20 min) and low solid to liquid ratio (1:3, 1:6) allowed effective extraction of carbohydrates from SBP and provided positive effect on subsequent enzymatic hydrolysis. The highest obtained concentration of reducing substances (RS) in hydrolysates was 8.5 %; up to 33.6 % of all carbohydrates present in SBP could be extracted. The major obtained monosaccharides were arabinose and glucose (9.4 and 7.3 g/l, respectively). Pretreatment of SBP with sulfurous acid increased 4.6 times the yield of glucose during subsequent enzymatic hydrolysis of remaining solids with cellulase cocktail, as compared to the untreated SBP. Total yield of glucose during SBP pretreatment and subsequent enzymatic hydrolysis amounted to 89.4 % of the theoretical yield. The approach can be applied directly to the wet SBP. Hydrolysis of sugar beet pulp with sulfurous acid is recommended for obtaining of individual monosaccharides, as well as nutritional media.

  2. Fractionation of oats into products enriched with protein, beta-glucan, starch, or other carbohydrates

    Technology Transfer Automated Retrieval System (TEKTRAN)

    A modified wet method was developed to fractionate ground oat groats into 4 fractions enriched with beta-glucan (BG), protein, starch, and other carbohydrates (CHO), respectively. Effects of defatting oats and centrifuge force for separation were also investigated. Results show that, depending on ...

  3. Transient decrements in mood during energy deficit are independent of dietary protein-to-carbohydrate ratio

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Energy deficit and dietary macronutrient intake are thought to independently modulate cognition, mood and sleep. To what extent manipulating the dietary ratio of protein-to-carbohydrate affects mood, cognition and sleep during short-term energy deficit is undetermined. Using a randomized, block desi...

  4. Analysis and quality control of carbohydrates in therapeutic proteins with fluorescence HPLC.

    PubMed

    Liu, Kun; Huang, Jian; Luo, Delun; Xu, Kai; Wu, Zhigang; Xu, Xun

    2016-09-16

    Conbercept is an Fc fusion protein with very complicated carbohydrate profiles which must be carefully monitored through manufacturing process. Here, we introduce an optimized fluorescence derivatization high-performance liquid chromatographic method for glycan mapping in conbercept. Compared with conventional glycan analysis method, this method has much better resolution and higher reproducibility making it excellent for product quality control. PMID:27514451

  5. Impact of dietary carbohydrate and protein source and content on swine manure foaming properties

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Diet ingredients are thought to contribute to foaming problems associated with swine deep-pit systems. Two experiments explored the impact of protein and carbohydrate sources in swine diets on the physicochemical properties, methane production potential, and foaming characteristics of swine manure. ...

  6. Reaction of protein and carbohydrates with EDC for purpose of making products with unique functional properties

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Prior research from this laboratory has demonstrated the feasibility of using chemical and enzymatic treatments on protein and carbohydrate waste products for the purpose of making fillers to enhance the properties of leather. These treatments (microbial transglutaminase, genipin, and polyphenols i...

  7. Protein and Carbohydrate Contents of Plant Seeds: An Introduction to Biochemical Analysis

    ERIC Educational Resources Information Center

    Deutch, Charles E.; Egan, Todd P.; Meekins, J. Forrest; Siegel, Carol

    2004-01-01

    The first of two projects developed for an introductory biology course of science majors titled Biological Concepts I is described. Students were divided into groups and were asked to determine the total amount of protein and carbohydrate in different types of seeds that were provided to them.

  8. Systemic Glucose Level Changes with a Carbohydrate-Restricted and Higher Protein Diet Combined with Exercise

    ERIC Educational Resources Information Center

    Bowden, Rodney G.; Lanning, Beth A.; Doyle, Eva I.; Slonaker, Becky; Johnston, Holly M.; Scanes, Georgene

    2007-01-01

    Objective: The authors' purpose in this study was to compare the effects of macronutrient intake on systemic glucose levels in previously sedentary participants who followed 1 of 4 diets that were either higher protein or high carbohydrate, while initiating an exercise program. Participants and Methods: The authors randomly assigned 94 sedentary…

  9. Reaction of protein and carbohydrates with EDC for making unique biomaterials

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Prior research from this laboratory has demonstrated the feasibility of using chemical and enzymatic treatments on protein and carbohydrate waste products for the purpose of making fillers to enhance the properties of leather. These treatments (microbial transglutaminase, genipin, and polyphenols i...

  10. Update: The Digestion and Absorption of Carbohydrate and Protein: Role of the Small Intestine.

    ERIC Educational Resources Information Center

    Leese, H. J.

    1984-01-01

    Discusses the role of the small intestine in the digestion and absorption of carbohydrates and proteins. Indicates as outdated the view that these materials must be broken down to monomeric units before absorption and that the gut secretes a mixture of digestive juices which brings about absorption. (JN)

  11. Protein v. carbohydrate intake differentially affects liking- and wanting-related brain signalling.

    PubMed

    Born, Jurriaan M; Martens, Mieke J I; Lemmens, Sofie G T; Goebel, Rainer; Westerterp-Plantenga, Margriet S

    2013-01-28

    Extreme macronutrient intakes possibly lead to different brain signalling. The aim of the present study was to determine the effects of ingesting high-protein v. high-carbohydrate food on liking and wanting task-related brain signalling (TRS) and subsequent macronutrient intake. A total of thirty female subjects (21.6 (SD 2.2) years, BMI 25.0 (SD 3.7) kg/m²) completed four functional MRI scans: two fasted and two satiated on two different days. During the scans, subjects rated all food items for liking and wanting, thereby choosing the subsequent meal. The results show that high-protein (PROT) v. high-carbohydrate (CARB) conditions were generated using protein or carbohydrate drinks at the first meal. Energy intake and hunger were recorded. PROT (protein: 53.7 (SD 2.1) percentage of energy (En%); carbohydrate: 6.4 (SD 1.3) En%) and CARB conditions (protein: 11.8 (SD 0.6) En%; carbohydrate: 70.0 (SD 2.4) En%) were achieved during the first meal, while the second meals were not different between the conditions. Hunger, energy intake, and behavioural liking and wanting ratings were decreased after the first meal (P< 0.001). Comparing the first with the second meal, the macronutrient content changed: carbohydrate -26.9 En% in the CARB condition, protein -37.8 En% in the PROT condition. After the first meal in the CARB condition, wanting TRS was increased in the hypothalamus. After the first meal in the PROT condition, liking TRS was decreased in the putamen (P< 0.05). The change in energy intake from the first to the second meal was inversely related to the change in liking TRS in the striatum and hypothalamus in the CARB condition and positively related in the PROT condition (P< 0.05). In conclusion, wanting and liking TRS were affected differentially with a change in carbohydrate or protein intake, underscoring subsequent energy intake and shift in macronutrient composition. PMID:22643242

  12. Activation of hypothalamic serotonin receptors reduced intake of dietary fat and protein but not carbohydrate.

    PubMed

    Smith, B K; York, D A; Bray, G A

    1999-09-01

    Systemic treatment with dexfenfluramine (dF), fluoxetine, or serotonin (5-hydroxytryptamine, 5-HT) recently was shown to suppress fat and occasionally protein but not carbohydrate intake in rats when a macronutrient selection paradigm was employed. These reports contrast with the prevailing literature, which for the past decade has described a role for serotonin neurotransmission in the modification of dietary carbohydrate consumption. To test the hypothesis that the suppression of fat selection and/or consumption by systemic serotonin agonists involves stimulation of central 5-HT receptors, a series of experiments was performed in nondeprived rats. In experiment 1, third cerebroventricular (3V) infusion of the nonselective 5-HT antagonist metergoline prevented the reduction in fat but not carbohydrate feeding caused by systemic dF. Furthermore, 3V metergoline alone increased fat intake. In experiments 2 and 3, 3V infusion of 5-HT(1B/2C) receptor agonists D-norfenfluramine (DNF) or quipazine inhibited fat intake exclusively. Next, the infusion of DNF or 5-HT into the region of the paraventricular nucleus (PVN) reduced both fat and protein intake (experiments 4 and 5). Finally, in experiment 6, when rats were grouped by baseline diet preference, 5-HT infused into the PVN led to a dose-related decrease in fat intake in both carbohydrate- and fat-preferring rats. In contrast, there were no dose effects of 5-HT on carbohydrate or protein intake in either preference group. However, in fat-preferring rats, the highest dose of 5-HT reduced intake of all three macronutrient diets. These results demonstrate a selective effect of exogenous serotonergic drugs in the hypothalamus to reduce fat rather than carbohydrate intake and suggest that higher baseline fat intake enhances responsivity to serotonergic drugs.

  13. Rapid Analysis of Listeria monocytogenes Cell Wall Teichoic Acid Carbohydrates by ESI-MS/MS

    PubMed Central

    Eugster, Marcel R.; Loessner, Martin J.

    2011-01-01

    We report the application of electrospray ionization (ESI) mass spectrometry for compositional characterization of wall teichoic acids (WTA), a major component of Gram-positive bacterial cell walls. Tandem mass spectrometry (ESI-MS/MS) of purified and chemically hydrolyzed monomeric WTA components provided sufficient information to identify WTA monomers and their specific carbohydrate constituents. A lithium matrix was used for ionization of uncharged WTA monomers, and successfully applied to analyze the WTA molecules of four Listeria strains differing in carbohydrate substitution on a conserved polyribitol-phosphate backbone structure. Carbohydrate residues such as N-acetylglucosamine or rhamnose linked to the WTA could directly be identified by ESI-MS/MS, circumventing the need for quantitative analysis by gas chromatography. The presence of a terminal N-acetylglucosamine residue tethered to the ribitol was confirmed using fluorescently labeled wheat-germ agglutinin. In conclusion, the mass spectrometry method described here will greatly facilitate compositional analysis and characterization of teichoic acids and similar macromolecules from diverse bacterial species, and represents a significant advance in the identification of serovar-specific carbohydrates and sugar molecules on bacteria. PMID:21738682

  14. Intrauterine Growth Retarded Progeny of Pregnant Sows Fed High Protein:Low Carbohydrate Diet Is Related to Metabolic Energy Deficit

    PubMed Central

    Metges, Cornelia C.; Lang, Iris S.; Hennig, Ulf; Brüssow, Klaus-Peter; Kanitz, Ellen; Tuchscherer, Margret; Schneider, Falk; Weitzel, Joachim M.; Steinhoff-Ooster, Anika; Sauerwein, Helga; Bellmann, Olaf; Nürnberg, Gerd; Rehfeldt, Charlotte; Otten, Winfried

    2012-01-01

    High and low protein diets fed to pregnant adolescent sows led to intrauterine growth retardation (IUGR). To explore underlying mechanisms, sow plasma metabolite and hormone concentrations were analyzed during different pregnancy stages and correlated with litter weight (LW) at birth, sow body weight and back fat thickness. Sows were fed diets with low (6.5%, LP), adequate (12.1%, AP), and high (30%, HP) protein levels, made isoenergetic by adjusted carbohydrate content. At −5, 24, 66, and 108 days post coitum (dpc) fasted blood was collected. At 92 dpc, diurnal metabolic profiles were determined. Fasted serum urea and plasma glucagon were higher due to the HP diet. High density lipoprotein cholesterol (HDLC), %HDLC and cortisol were reduced in HP compared with AP sows. Lowest concentrations were observed for serum urea and protein, plasma insulin-like growth factor-I, low density lipoprotein cholesterol, and progesterone in LP compared with AP and HP sows. Fasted plasma glucose, insulin and leptin concentrations were unchanged. Diurnal metabolic profiles showed lower glucose in HP sows whereas non-esterified fatty acids (NEFA) concentrations were higher in HP compared with AP and LP sows. In HP and LP sows, urea concentrations were 300% and 60% of AP sows, respectively. Plasma total cholesterol was higher in LP than in AP and HP sows. In AP sows, LW correlated positively with insulin and insulin/glucose and negatively with glucagon/insulin at 66 dpc, whereas in HP sows LW associated positively with NEFA. In conclusion, IUGR in sows fed high protein∶low carbohydrate diet was probably due to glucose and energy deficit whereas in sows with low protein∶high carbohydrate diet it was possibly a response to a deficit of indispensable amino acids which impaired lipoprotein metabolism and favored maternal lipid disposal. PMID:22328932

  15. Effect of carbohydrate-protein supplementation postexercise on rat muscle glycogen synthesis and phosphorylation of proteins controlling glucose storage.

    PubMed

    Hara, Daisuke; Morrison, Paul J; Ding, Zhenping; Ivy, John L

    2011-10-01

    To examine whether addition of protein to a carbohydrate supplement enhances muscle glycogen synthesis, we compared the muscle glycogen concentrations of rats that had been depleted of their muscle glycogen stores with a 3-hour swim and immediately supplemented with a placebo (Con), carbohydrate (CHO), or carbohydrate plus protein supplement (C+P). Rats were given either 0.9 g carbohydrate per kilogram body mass for the CHO group or 0.9 g carbohydrate + 0.3 g protein per kilogram body mass for the C+P groups. Muscle samples of the red and white quadriceps were excised immediately, 30 minutes, or 90 minutes postexercise. Glycogen concentration of the C+P group was greater than that of the CHO group at 90 minutes postexercise in both red (C+P, 28.3 ± 2.6 µmol/g vs CHO, 22.4 ± 2.0 µmol/g; P < .05) and white (C+P, 24.9 ± 2.4 µmol/g vs CHO, 17.64 ± 1.5 µmol/g; P < .01) quadriceps. Protein kinase B phosphorylation was greater in the C+P-30 group (the number following treatment group abbreviation refers to time [in minutes] of euthanasia following exercise) than the sedentary control and exercised control groups in red quadriceps at 30 minutes and in white quadriceps at 90 minutes postexercise. This difference was not observed in the CHO group. Phosphorylation of glycogen synthase was significantly reduced 30 minutes postexercise and returned to baseline levels by 90 minutes postexercise in both CHO- and C+P-supplemented groups, with no difference between supplements. These results demonstrated that the addition of protein to a carbohydrate supplement will enhance the rate of muscle glycogen restoration postexercise and may involve facilitation of the glucose transport process.

  16. Patterns of carbohydrate and fatty acid changes under nitrogen starvation in the microalgae Haematococcus pluvialis and Nannochloropsis sp.

    PubMed

    Recht, Lee; Zarka, Aliza; Boussiba, Sammy

    2012-06-01

    The aim of this research was to study the impact of nitrogen starvation on the production of two major secondary metabolites, fatty acids and carbohydrates, in two microalgae: Nannochloropsis sp. and Haematococcus pluvialis. The major response to nitrogen starvation in both algae occurred within the first 2 days, accompanied by a sharp reduction in chlorophyll content. However, the pattern of the response differed between the two microalgae. In H. pluvialis, the first response to nitrogen starvation was intensive production of carbohydrates, accumulating to up to 63% of dry weight by day 1; on day 2, the total carbohydrate content decreased and was partially degraded, possibly to support fatty acid synthesis. Under these conditions, H. pluvialis accumulated up to 35% total fatty acids in the biomass. In Nannochloropsis sp., the immediate and major response, which was maintained throughout the entire period of exposure to stress, was production of fatty acids, accumulating up to 50% of dry weight, while carbohydrate content in the biomass remained stable at 18%. In addition, we tested the effect of the lipid-synthesis inhibitor sesamol, known to inhibit malic enzyme, on the balance between total fatty acid and carbohydrate contents in H. pluvialis and Nannochloropsis sp. In both cultures, sesamol inhibited fatty acid accumulation, but the carbohydrate content was reduced as well, albeit to a lesser extent. These findings demonstrate the complexity of the stress-response and the potential link between fatty acid and carbohydrate synthesis.

  17. Gallic acid ameliorates hyperglycemia and improves hepatic carbohydrate metabolism in rats fed a high-fructose diet.

    PubMed

    Huang, Da-Wei; Chang, Wen-Chang; Wu, James Swi-Bea; Shih, Rui-Wen; Shen, Szu-Chuan

    2016-02-01

    Herein, we investigated the hypoglycemic effect of plant gallic acid (GA) on glucose uptake in an insulin-resistant cell culture model and on hepatic carbohydrate metabolism in rats with a high-fructose diet (HFD)-induced diabetes. Our hypothesis is that GA ameliorates hyperglycemia via alleviating hepatic insulin resistance by suppressing hepatic inflammation and improves abnormal hepatic carbohydrate metabolism by suppressing hepatic gluconeogenesis and enhancing the hepatic glycogenesis and glycolysis pathways in HFD-induced diabetic rats. Gallic acid increased glucose uptake activity by 19.2% at a concentration of 6.25 μg/mL in insulin-resistant FL83B mouse hepatocytes. In HFD-induced diabetic rats, GA significantly alleviated hyperglycemia, reduced the values of the area under the curve for glucose in an oral glucose tolerance test, and reduced the scores of the homeostasis model assessment of insulin resistance index. The levels of serum C-peptide and fructosamine and cardiovascular risk index scores were also significantly decreased in HFD rats treated with GA. Moreover, GA up-regulated the expression of hepatic insulin signal transduction-related proteins, including insulin receptor, insulin receptor substrate 1, phosphatidylinositol-3 kinase, Akt/protein kinase B, and glucose transporter 2, in HFD rats. Gallic acid also down-regulated the expression of hepatic gluconeogenesis-related proteins, such as fructose-1,6-bisphosphatase, and up-regulated expression of hepatic glycogen synthase and glycolysis-related proteins, including hexokinase, phosphofructokinase, and aldolase, in HFD rats. Our findings indicate that GA has potential as a health food ingredient to prevent diabetes mellitus.

  18. Differential Amino Acid, Carbohydrate and Lipid Metabolism Perpetuations Involved in a Subtype of Rheumatoid Arthritis with Chinese Medicine Cold Pattern

    PubMed Central

    Guo, Hongtao; Niu, Xuyan; Gu, Yan; Lu, Cheng; Xiao, Cheng; Yue, Kevin; Zhang, Ge; Pan, Xiaohua; Jiang, Miao; Tan, Yong; Kong, Hongwei; Liu, Zhenli; Xu, Guowang; Lu, Aiping

    2016-01-01

    Pattern classification is a key approach in Traditional Chinese Medicine (TCM), and it is used to classify the patients for intervention selection accordingly. TCM cold and heat patterns, two main patterns of rheumatoid arthritis (RA) had been explored with systems biology approaches. Different regulations of apoptosis were found to be involved in cold and heat classification in our previous works. For this study, the metabolic profiling of plasma was explored in RA patients with typical TCM cold or heat patterns by integrating liquid chromatography/mass spectrometry (LC/MS) and gas chromatography/mass spectrometry (GC/MS) platforms in conjunction with the Ingenuity Pathway Analysis (IPA) software. Three main processes of metabolism, including amino acid, carbohydrate and lipid were focused on for function analysis. The results showed that 29 and 19 differential metabolites were found in cold and heat patterns respectively, compared with healthy controls. The perturbation of amino acid metabolism (increased essential amino acids), carbohydrate metabolism (galactose metabolism) and lipid metabolism, were found to be involved in both cold and heat pattern RA. In particular, more metabolic perturbations in protein and collagen breakdown, decreased glycolytic activity and aerobic oxidation, and increased energy utilization associated with RA cold pattern patients. These findings may be useful for obtaining a better understanding of RA pathogenesis and for achieving a better efficacy in RA clinical practice. PMID:27775663

  19. Nutritional balance of essential amino acids and carbohydrates of the adult worker honeybee depends on age.

    PubMed

    Paoli, Pier P; Donley, Dion; Stabler, Daniel; Saseendranath, Anumodh; Nicolson, Susan W; Simpson, Stephen J; Wright, Geraldine A

    2014-06-01

    Dietary sources of essential amino acids (EAAs) are used for growth, somatic maintenance and reproduction. Eusocial insect workers such as honeybees are sterile, and unlike other animals, their nutritional needs should be largely dictated by somatic demands that arise from their role within the colony. Here, we investigated the extent to which the dietary requirements of adult worker honeybees for EAAs and carbohydrates are affected by behavioural caste using the Geometric Framework for nutrition. The nutritional optimum, or intake target (IT), was determined by confining cohorts of 20 young bees or foragers to liquid diets composed of specific proportions of EAAs and sucrose. The IT of young, queenless bees shifted from a proportion of EAAs-to-carbohydrates (EAA:C) of 1:50 towards 1:75 over a 2-week period, accompanied by a reduced lifespan on diets high in EAAs. Foragers required a diet high in carbohydrates (1:250) and also had low survival on diets high in EAA. Workers exposed to queen mandibular pheromone lived longer on diets high in EAA, even when those diets contained 5× their dietary requirements. Our data show that worker honeybees prioritize their intake of carbohydrates over dietary EAAs, even when overeating EAAs to obtain sufficient carbohydrates results in a shorter lifespan. Thus, our data demonstrate that even when young bees are not nursing brood and foragers are not flying, their nutritional needs shift towards a diet largely composed of carbohydrates when they make the transition from within-hive duties to foraging. PMID:24623119

  20. The role of Monosaccharide Transport Proteins in carbohydrate assimilation, distribution, metabolism and homeostasis

    PubMed Central

    Cura, Anthony J.; Carruthers, Anthony

    2012-01-01

    The facilitated diffusion of glucose, galactose, fructose, urate, myoinositol and dehydroascorbic acid in mammals is catalyzed by a family of 14 monosaccharide transport proteins called GLUTs. These transporters may be divided into 3 classes according to sequence similarity and function/substrate specificity. GLUT1 appears to be highly expressed in glycolytically active cells and has been co-opted in vitamin C auxotrophs to maintain the redox state of the blood through transport of dehydroascorbate. Several GLUTs are definitive glucose/galactose transporters, GLUT2 and GLUT5 are physiologically important fructose transporters, GLUT9 appears to be a urate transporter while GLUT13 (HMIT1) is a proton/myoinositol co-transporter. The physiologic substrates of some GLUTs remain to be established. The GLUTs are expressed in a tissue specific manner where affinity, specificity and capacity for substrate transport are paramount for tissue function. Although great strides have been made in characterizing GLUT-catalyzed monosaccharide transport and mapping GLUT membrane topography and determinants of substrate specificity, a unifying model for GLUT structure and function remains elusive. The GLUTs play a major role in carbohydrate homeostasis and the redistribution of sugar-derived carbons among the various organ systems. This is accomplished through a multiplicity of GLUT-dependent glucose sensing and effector mechanisms that regulate monosaccharide ingestion, absorption, distribution, cellular transport and metabolism and recovery/retention. Glucose transport and metabolism have co-evolved in mammals to support cerebral glucose utilization. PMID:22943001

  1. Optimizing intramuscular adaptations to aerobic exercise: effects of carbohydrate restriction and protein supplementation on mitochondrial biogenesis.

    PubMed

    Margolis, Lee M; Pasiakos, Stefan M

    2013-11-01

    Mitochondrial biogenesis is a critical metabolic adaptation to aerobic exercise training that results in enhanced mitochondrial size, content, number, and activity. Recent evidence has shown that dietary manipulation can further enhance mitochondrial adaptations to aerobic exercise training, which may delay skeletal muscle fatigue and enhance exercise performance. Specifically, studies have demonstrated that combining carbohydrate restriction (endogenous and exogenous) with a single bout of aerobic exercise potentiates the beneficial effects of exercise on markers of mitochondrial biogenesis. Additionally, studies have demonstrated that high-quality protein supplementation enhances anabolic skeletal muscle intracellular signaling and mitochondrial protein synthesis following a single bout of aerobic exercise. Mitochondrial biogenesis is stimulated by complex intracellular signaling pathways that appear to be primarily regulated by 5'AMP-activated protein kinase and p38 mitogen-activated protein kinase mediated through proliferator-activated γ receptor co-activator 1 α activation, resulting in increased mitochondrial DNA expression and enhanced skeletal muscle oxidative capacity. However, the mechanisms by which concomitant carbohydrate restriction and dietary protein supplementation modulates mitochondrial adaptations to aerobic exercise training remains unclear. This review summarizes intracellular regulation of mitochondrial biogenesis and the effects of carbohydrate restriction and protein supplementation on mitochondrial adaptations to aerobic exercise.

  2. Moderate carbohydrate, moderate protein weight loss diet reduces cardiovascular disease risk compared to high carbohydrate, low protein diet in obese adults: A randomized clinical trial

    PubMed Central

    Lasker, Denise A Walker; Evans, Ellen M; Layman, Donald K

    2008-01-01

    Background To evaluate the metabolic effects of two weight loss diets differing in macronutrient composition on features of dyslipidemia and post-prandial insulin (INS) response to a meal challenge in overweight/obese individuals. Methods This study was a parallel-arm randomized 4 mo weight loss trial. Adults (n = 50, 47 ± 7 y) matched on BMI (33.6 ± 0.6 kg/m2, P = 0.79) consumed energy restricted diets (deficit ~500 kcal/d): PRO (1.6 g.kg-1.d-1 protein and < 170 g/d carbohydrate) or CHO (0.8 g.kg-1.d-1 protein and > 220 g/d carbohydrate) for 4 mos. Meal challenges of respective diets were utilized for determination of blood lipids and post-prandial INS and glucose response at the beginning and end of the study. Results There was a trend for PRO to lose more weight (-9.1% vs. -7.3%, P = 0.07) with a significant reduction in percent fat mass compared to CHO (-8.7% vs. -5.7%; P = 0.03). PRO also favored reductions in triacylglycerol (-34% vs. -14%; P < 0.05) and increases in HDL-C (+5% vs. -3%; P = 0.05); however, CHO favored reduction in LDL-C (-7% vs. +2.5%; P < 0.05). INS responses to the meal challenge were improved in PRO compared to CHO (P < 0.05) at both 1 hr (-34.3% vs. -1.0%) and 2 hr (-9.2% vs. +46.2%), an effect that remained significant after controlling for weight or fat loss (both P < 0.05). Conclusion A weight loss diet with moderate carbohydrate, moderate protein results in more favorable changes in body composition, dyslipidemia, and post-prandial INS response compared to a high carbohydrate, low protein diet suggesting an additional benefit beyond weight management to include augmented risk reduction for metabolic disease. PMID:18990242

  3. Glycosylated Conductive Polymer: A Multimodal Biointerface for Studying Carbohydrate-Protein Interactions.

    PubMed

    Zeng, Xiangqun; Qu, Ke; Rehman, Abdul

    2016-09-20

    Carbohydrate-protein interactions occur through glycoproteins, glycolipids, or polysaccharides displayed on the cell surface with lectins. However, studying these interactions is challenging because of the complexity and heterogeneity of the cell surface, the inherent structural complexity of carbohydrates, and the typically weak affinities of the binding reactions between the lectins and monovalent carbohydrates. The lack of chromophores and fluorophores in carbohydrate structures often drives such investigations toward fluorescence labeling techniques, which usually require tedious and complex synthetic work to conjugate fluorescent tags with additional risk of altering the reaction dynamics. Probing these interactions directly on the cell surface is even more difficult since cells could be too fragile for labeling or labile dynamics could be affected by the labeled molecules that may interfere with the cellular activities, resulting in unwanted cell responses. In contrast, label-free biosensors allow real-time monitoring of carbohydrate-protein interactions in their natural states. A prerequisite, though, for this strategy to work is to mimic the coding information on potential interactions of cell surfaces onto different biosensing platforms, while the complementary binding process can be transduced into a useful signal noninvasively. Through carbohydrate self-assembled monolayers and glycopolymer scaffolds, the multivalency of the naturally existing simple and complex carbohydrates can be mimicked and exploited with label-free readouts (e.g., optical, acoustic, mechanical, electrochemical, and electrical sensors), yet such inquiries reflect only limited aspects of complicated biointeraction processes due to the unimodal transduction. In this Account, we illustrate that functionalized glycosylated conductive polymer scaffolds are the ideal multimodal biointerfaces that not only simplify the immobilization process for surface fabrication via electrochemical

  4. Glycosylated Conductive Polymer: A Multimodal Biointerface for Studying Carbohydrate-Protein Interactions.

    PubMed

    Zeng, Xiangqun; Qu, Ke; Rehman, Abdul

    2016-09-20

    Carbohydrate-protein interactions occur through glycoproteins, glycolipids, or polysaccharides displayed on the cell surface with lectins. However, studying these interactions is challenging because of the complexity and heterogeneity of the cell surface, the inherent structural complexity of carbohydrates, and the typically weak affinities of the binding reactions between the lectins and monovalent carbohydrates. The lack of chromophores and fluorophores in carbohydrate structures often drives such investigations toward fluorescence labeling techniques, which usually require tedious and complex synthetic work to conjugate fluorescent tags with additional risk of altering the reaction dynamics. Probing these interactions directly on the cell surface is even more difficult since cells could be too fragile for labeling or labile dynamics could be affected by the labeled molecules that may interfere with the cellular activities, resulting in unwanted cell responses. In contrast, label-free biosensors allow real-time monitoring of carbohydrate-protein interactions in their natural states. A prerequisite, though, for this strategy to work is to mimic the coding information on potential interactions of cell surfaces onto different biosensing platforms, while the complementary binding process can be transduced into a useful signal noninvasively. Through carbohydrate self-assembled monolayers and glycopolymer scaffolds, the multivalency of the naturally existing simple and complex carbohydrates can be mimicked and exploited with label-free readouts (e.g., optical, acoustic, mechanical, electrochemical, and electrical sensors), yet such inquiries reflect only limited aspects of complicated biointeraction processes due to the unimodal transduction. In this Account, we illustrate that functionalized glycosylated conductive polymer scaffolds are the ideal multimodal biointerfaces that not only simplify the immobilization process for surface fabrication via electrochemical

  5. Carminic acid-promoted oxygen radical damage to lipid and carbohydrate.

    PubMed

    Gutteridge, J M; Quinlan, G J

    1986-01-01

    The food colouring carminic acid redox cycles to produce free radicals. These radicals, in the presence of trace amounts of iron salts, readily damage membrane lipid and degrade the carbohydrate deoxyribose. Damage to membrane lipid appears to involve mainly organic oxygen radicals such as alkoxy and peroxy radicals, whereas that to deoxyribose implicates the hydroxyl radical formed in a Fenton-type reaction. Antioxidants and iron chelators prevent such damage. PMID:3803637

  6. The Bacterial Phosphoenolpyruvate:Carbohydrate Phosphotransferase System: Regulation by Protein Phosphorylation and Phosphorylation-Dependent Protein-Protein Interactions

    PubMed Central

    Aké, Francine Moussan Désirée; Derkaoui, Meriem; Zébré, Arthur Constant; Cao, Thanh Nguyen; Bouraoui, Houda; Kentache, Takfarinas; Mokhtari, Abdelhamid; Milohanic, Eliane; Joyet, Philippe

    2014-01-01

    SUMMARY The bacterial phosphoenolpyruvate (PEP):carbohydrate phosphotransferase system (PTS) carries out both catalytic and regulatory functions. It catalyzes the transport and phosphorylation of a variety of sugars and sugar derivatives but also carries out numerous regulatory functions related to carbon, nitrogen, and phosphate metabolism, to chemotaxis, to potassium transport, and to the virulence of certain pathogens. For these different regulatory processes, the signal is provided by the phosphorylation state of the PTS components, which varies according to the availability of PTS substrates and the metabolic state of the cell. PEP acts as phosphoryl donor for enzyme I (EI), which, together with HPr and one of several EIIA and EIIB pairs, forms a phosphorylation cascade which allows phosphorylation of the cognate carbohydrate bound to the membrane-spanning EIIC. HPr of firmicutes and numerous proteobacteria is also phosphorylated in an ATP-dependent reaction catalyzed by the bifunctional HPr kinase/phosphorylase. PTS-mediated regulatory mechanisms are based either on direct phosphorylation of the target protein or on phosphorylation-dependent interactions. For regulation by PTS-mediated phosphorylation, the target proteins either acquired a PTS domain by fusing it to their N or C termini or integrated a specific, conserved PTS regulation domain (PRD) or, alternatively, developed their own specific sites for PTS-mediated phosphorylation. Protein-protein interactions can occur with either phosphorylated or unphosphorylated PTS components and can either stimulate or inhibit the function of the target proteins. This large variety of signal transduction mechanisms allows the PTS to regulate numerous proteins and to form a vast regulatory network responding to the phosphorylation state of various PTS components. PMID:24847021

  7. Analyzing Carbohydrate-Protein Interaction Based on Single Plasmonic Nanoparticle by Conventional Dark Field Microscopy.

    PubMed

    Jin, Hong-Ying; Li, Da-Wei; Zhang, Na; Gu, Zhen; Long, Yi-Tao

    2015-06-10

    We demonstrated a practical method to analyze carbohydrate-protein interaction based on single plasmonic nanoparticles by conventional dark field microscopy (DFM). Protein concanavalin A (ConA) was modified on large sized gold nanoparticles (AuNPs), and dextran was conjugated on small sized AuNPs. As the interaction between ConA and dextran resulted in two kinds of gold nanoparticles coupled together, which caused coupling of plasmonic oscillations, apparent color changes (from green to yellow) of the single AuNPs were observed through DFM. Then, the color information was instantly transformed into a statistic peak wavelength distribution in less than 1 min by a self-developed statistical program (nanoparticleAnalysis). In addition, the interaction between ConA and dextran was proved with biospecific recognition. This approach is high-throughput and real-time, and is a convenient method to analyze carbohydrate-protein interaction at the single nanoparticle level efficiently. PMID:25985863

  8. Carbohydrate Loading.

    ERIC Educational Resources Information Center

    Csernus, Marilyn

    Carbohydrate loading is a frequently used technique to improve performance by altering an athlete's diet. The objective is to increase glycogen stored in muscles for use in prolonged strenuous exercise. For two to three days, the athlete consumes a diet that is low in carbohydrates and high in fat and protein while continuing to exercise and…

  9. Evolutionary bases of carbohydrate recognition and substrate discrimination in the ROK protein family.

    PubMed

    Conejo, Maria S; Thompson, Steven M; Miller, Brian G

    2010-06-01

    The ROK (repressor, open reading frame, kinase) protein family (Pfam 00480) is a large collection of bacterial polypeptides that includes sugar kinases, carbohydrate responsive transcriptional repressors, and many functionally uncharacterized gene products. ROK family sugar kinases phosphorylate a range of structurally distinct hexoses including the key carbon source D: -glucose, various glucose epimers, and several acetylated hexosamines. The primary sequence elements responsible for carbohydrate recognition within different functional categories of ROK polypeptides are largely unknown due to a limited structural characterization of this protein family. In order to identify the structural bases for substrate discrimination in individual ROK proteins, and to better understand the evolutionary processes that led to the divergent evolution of function in this family, we constructed an inclusive alignment of 227 representative ROK polypeptides. Phylogenetic analyses and ancestral sequence reconstructions of the resulting tree reveal a discrete collection of active site residues that dictate substrate specificity. The results also suggest a series of mutational events within the carbohydrate-binding sites of ROK proteins that facilitated the expansion of substrate specificity within this family. This study provides new insight into the evolutionary relationship of ROK glucokinases and non-ROK glucokinases (Pfam 02685), revealing the primary sequence elements shared between these two protein families, which diverged from a common ancestor in ancient times. PMID:20512568

  10. Protein-Carbohydrate Interaction between Sperm and the Egg-Coating Envelope and Its Regulation by Dicalcin, a Xenopus laevis Zona Pellucida Protein-Associated Protein.

    PubMed

    Miwa, Naofumi

    2015-05-22

    Protein-carbohydrate interaction regulates multiple important processes during fertilization, an essential biological event where individual gametes undergo intercellular recognition to fuse and generate a zygote. In the mammalian female reproductive tract, sperm temporarily adhere to the oviductal epithelium via the complementary interaction between carbohydrate-binding proteins on the sperm membrane and carbohydrates on the oviductal cells. After detachment from the oviductal epithelium at the appropriate time point following ovulation, sperm migrate and occasionally bind to the extracellular matrix, called the zona pellucida (ZP), which surrounds the egg, thereafter undergoing the exocytotic acrosomal reaction to penetrate the envelope and to reach the egg plasma membrane. This sperm-ZP interaction also involves the direct interaction between sperm carbohydrate-binding proteins and carbohydrates within the ZP, most of which have been conserved across divergent species from mammals to amphibians and echinoderms. This review focuses on the carbohydrate-mediated interaction of sperm with the female reproductive tract, mainly the interaction between sperm and the ZP, and introduces the fertilization-suppressive action of dicalcin, a Xenopus laevis ZP protein-associated protein. The action of dicalcin correlates significantly with a dicalcin-dependent change in the lectin-staining pattern within the ZP, suggesting a unique role of dicalcin as an inherent protein that is capable of regulating the affinity between the lectin and oligosaccharides attached on its target glycoprotein.

  11. Balancing of lipid, protein, and carbohydrate intake in a predatory beetle following hibernation, and consequences for lipid restoration.

    PubMed

    Noreika, Norbertas; Madsen, Natalia E L; Jensen, Kim; Toft, Søren

    2016-05-01

    Carnivorous animals are known to balance their consumption of lipid and protein, and recent studies indicate that some mammalian carnivores also regulate their intake of carbohydrate. We investigated macronutrient balancing and lipid restoration following hibernation in the ground beetle Anchomenus dorsalis, hypothesizing that carbohydrates might be important energy sources upon hibernation when predator lipid stores are exhausted and prey are equally lean. We recorded the consumption of lipid, protein, and carbohydrate over nine days following hibernation, as the beetles foraged to refill their lipid stores. Each beetle was given the opportunity to regulate consumption from two semi-artificial foods differing in the proportion of two of the three macronutrients, while the third macronutrient was kept constant. When analyzing consumption of the three macronutrients on an energetic basis, it became apparent that the beetles regulated lipid and carbohydrate energy interchangeably and balanced the combined energy intake from the two macronutrients against protein intake. Restoration of lipid stores was independent of the availability of any specific macronutrient. However, the energetic consumption required to refill lipid stores was higher when a low proportion of lipids was ingested, suggesting that lipids were readily converted into lipid stores while there were energetic costs associated with converting carbohydrate and protein into stored lipids. Our experiment demonstrates that carbohydrates are consumed and regulated as a non-protein energy source by A. dorsalis despite an expectedly low occurrence of carbohydrates in their natural diet. Perhaps carbohydrates are in fact an overlooked supplementary energy source in the diet of carnivorous arthropods.

  12. Balancing of lipid, protein, and carbohydrate intake in a predatory beetle following hibernation, and consequences for lipid restoration.

    PubMed

    Noreika, Norbertas; Madsen, Natalia E L; Jensen, Kim; Toft, Søren

    2016-05-01

    Carnivorous animals are known to balance their consumption of lipid and protein, and recent studies indicate that some mammalian carnivores also regulate their intake of carbohydrate. We investigated macronutrient balancing and lipid restoration following hibernation in the ground beetle Anchomenus dorsalis, hypothesizing that carbohydrates might be important energy sources upon hibernation when predator lipid stores are exhausted and prey are equally lean. We recorded the consumption of lipid, protein, and carbohydrate over nine days following hibernation, as the beetles foraged to refill their lipid stores. Each beetle was given the opportunity to regulate consumption from two semi-artificial foods differing in the proportion of two of the three macronutrients, while the third macronutrient was kept constant. When analyzing consumption of the three macronutrients on an energetic basis, it became apparent that the beetles regulated lipid and carbohydrate energy interchangeably and balanced the combined energy intake from the two macronutrients against protein intake. Restoration of lipid stores was independent of the availability of any specific macronutrient. However, the energetic consumption required to refill lipid stores was higher when a low proportion of lipids was ingested, suggesting that lipids were readily converted into lipid stores while there were energetic costs associated with converting carbohydrate and protein into stored lipids. Our experiment demonstrates that carbohydrates are consumed and regulated as a non-protein energy source by A. dorsalis despite an expectedly low occurrence of carbohydrates in their natural diet. Perhaps carbohydrates are in fact an overlooked supplementary energy source in the diet of carnivorous arthropods. PMID:26868725

  13. Localizing Carbohydrate Binding Sites in Proteins Using Hydrogen/Deuterium Exchange Mass Spectrometry

    NASA Astrophysics Data System (ADS)

    Zhang, Jingjing; Kitova, Elena N.; Li, Jun; Eugenio, Luiz; Ng, Kenneth; Klassen, John S.

    2016-01-01

    The application of hydrogen/deuterium exchange mass spectrometry (HDX-MS) to localize ligand binding sites in carbohydrate-binding proteins is described. Proteins from three bacterial toxins, the B subunit homopentamers of Cholera toxin and Shiga toxin type 1 and a fragment of Clostridium difficile toxin A, and their interactions with native carbohydrate receptors, GM1 pentasaccharides (β-Gal-(1→3)-β-GalNAc-(1→4)[α-Neu5Ac-(2→3)]-β-Gal-(1→4)-Glc), Pk trisaccharide (α-Gal-(1→4)-β-Gal-(1→4)-Glc) and CD-grease (α-Gal-(1→3)-β-Gal-(1→4)-β-GlcNAcO(CH2)8CO2CH3), respectively, served as model systems for this study. Comparison of the differences in deuterium uptake for peptic peptides produced in the absence and presence of ligand revealed regions of the proteins that are protected against deuterium exchange upon ligand binding. Notably, protected regions generally coincide with the carbohydrate binding sites identified by X-ray crystallography. However, ligand binding can also result in increased deuterium exchange in other parts of the protein, presumably through allosteric effects. Overall, the results of this study suggest that HDX-MS can serve as a useful tool for localizing the ligand binding sites in carbohydrate-binding proteins. However, a detailed interpretation of the changes in deuterium exchange upon ligand binding can be challenging because of the presence of ligand-induced changes in protein structure and dynamics.

  14. Localizing Carbohydrate Binding Sites in Proteins Using Hydrogen/Deuterium Exchange Mass Spectrometry.

    PubMed

    Zhang, Jingjing; Kitova, Elena N; Li, Jun; Eugenio, Luiz; Ng, Kenneth; Klassen, John S

    2016-01-01

    The application of hydrogen/deuterium exchange mass spectrometry (HDX-MS) to localize ligand binding sites in carbohydrate-binding proteins is described. Proteins from three bacterial toxins, the B subunit homopentamers of Cholera toxin and Shiga toxin type 1 and a fragment of Clostridium difficile toxin A, and their interactions with native carbohydrate receptors, GM1 pentasaccharides (β-Gal-(1→3)-β-GalNAc-(1→4)[α-Neu5Ac-(2→3)]-β-Gal-(1→4)-Glc), Pk trisaccharide (α-Gal-(1→4)-β-Gal-(1→4)-Glc) and CD-grease (α-Gal-(1→3)-β-Gal-(1→4)-β-GlcNAcO(CH2)8CO2CH3), respectively, served as model systems for this study. Comparison of the differences in deuterium uptake for peptic peptides produced in the absence and presence of ligand revealed regions of the proteins that are protected against deuterium exchange upon ligand binding. Notably, protected regions generally coincide with the carbohydrate binding sites identified by X-ray crystallography. However, ligand binding can also result in increased deuterium exchange in other parts of the protein, presumably through allosteric effects. Overall, the results of this study suggest that HDX-MS can serve as a useful tool for localizing the ligand binding sites in carbohydrate-binding proteins. However, a detailed interpretation of the changes in deuterium exchange upon ligand binding can be challenging because of the presence of ligand-induced changes in protein structure and dynamics.

  15. Diet structure, butyric acid, and fermentable carbohydrates influence growth performance, gut morphology, and cecal fermentation characteristics in broilers.

    PubMed

    Qaisrani, S N; van Krimpen, M M; Kwakkel, R P; Verstegen, M W A; Hendriks, W H

    2015-09-01

    An experiment with 288 male (Ross 308) 1-d-old broilers was conducted to test the hypothesis that a coarse diet supplemented with butyric acid (BA) and fermentable carbohydrates (FC) improves performance of broilers with a poorly digestible protein source. The interaction effects of diet structure (fine or coarse), FC supplementation (with or without), and BA supplementation (with or without) in a poorly digestible diet based on rapeseed meal (RSM) were tested in a factorial arrangement of 8 (2×2×2) dietary treatments. The coarseness of the diet affected feed intake (FI) (P<0.001), BW gain (P=0.001), and the feed conversion ratio (FCR) (P=0.001) positively. Broilers fed the coarse diets had, on average, 14% heavier gizzards and 11, 7, 5, and 6% lower relative empty weights of the crop, duodenum, jejunum, and ileum, respectively, compared with those fed the fine diets. Dietary coarseness resulted in, on average, 6% greater ileal protein digestibility, 20% lower gizzard pH, 19% greater villus height, 18% lower crypt depth, and 23% reduced cecal branched chain fatty acids (BCFA) compared with chickens fed the fine diets. Broilers fed BA-supplemented diets had an improved FCR (P=0.004) and decreased crypt depth (P<0.001) compared with those fed diets without BA. Fermentable carbohydrate supplementation did not influence growth performance, gut development, or contents of total BCFA and total biogenic amines in the cecal digesta (P>0.05). Supplementation with FC, however, decreased the cecal concentration of spermine by approximately 31% compared with broilers fed diets without FC (P=0.002). In conclusion, feeding a coarse diet supplemented with BA improved performance of broilers fed a diet containing a poorly digestible protein source. The negative effects of a poorly digestible protein source can thus be partly counterbalanced by coarse grinding and BA supplementation in the diet.

  16. Diet structure, butyric acid, and fermentable carbohydrates influence growth performance, gut morphology, and cecal fermentation characteristics in broilers

    PubMed Central

    Qaisrani, S. N.; van Krimpen, M. M.; Kwakkel, R. P.; Verstegen, M. W. A.; Hendriks, W. H.

    2015-01-01

    An experiment with 288 male (Ross 308) 1-d-old broilers was conducted to test the hypothesis that a coarse diet supplemented with butyric acid (BA) and fermentable carbohydrates (FC) improves performance of broilers with a poorly digestible protein source. The interaction effects of diet structure (fine or coarse), FC supplementation (with or without), and BA supplementation (with or without) in a poorly digestible diet based on rapeseed meal (RSM) were tested in a factorial arrangement of 8 (2 × 2 × 2) dietary treatments. The coarseness of the diet affected feed intake (FI) (P < 0.001), BW gain (P = 0.001), and the feed conversion ratio (FCR) (P = 0.001) positively. Broilers fed the coarse diets had, on average, 14% heavier gizzards and 11, 7, 5, and 6% lower relative empty weights of the crop, duodenum, jejunum, and ileum, respectively, compared with those fed the fine diets. Dietary coarseness resulted in, on average, 6% greater ileal protein digestibility, 20% lower gizzard pH, 19% greater villus height, 18% lower crypt depth, and 23% reduced cecal branched chain fatty acids (BCFA) compared with chickens fed the fine diets. Broilers fed BA-supplemented diets had an improved FCR (P = 0.004) and decreased crypt depth (P < 0.001) compared with those fed diets without BA. Fermentable carbohydrate supplementation did not influence growth performance, gut development, or contents of total BCFA and total biogenic amines in the cecal digesta (P > 0.05). Supplementation with FC, however, decreased the cecal concentration of spermine by approximately 31% compared with broilers fed diets without FC (P = 0.002). In conclusion, feeding a coarse diet supplemented with BA improved performance of broilers fed a diet containing a poorly digestible protein source. The negative effects of a poorly digestible protein source can thus be partly counterbalanced by coarse grinding and BA supplementation in the diet. PMID:26175052

  17. Synthesis and emulsifying properties of carbohydrate fatty acid esters produced from Agave tequilana fructans by enzymatic acylation.

    PubMed

    Casas-Godoy, Leticia; Arrizon, Javier; Arrieta-Baez, Daniel; Plou, Francisco J; Sandoval, Georgina

    2016-08-01

    Carbohydrate fatty acid esters are non-ionic surfactants with a broad spectrum of applications. These molecules are generally synthesized using short carbohydrates or linear fructans; however in this research carbohydrate fatty acid esters were produced for the first time with branched fructans from Agave tequilana. Using immobilized lipases we successfully acylated A. tequilana fructans with vinyl laurate, obtaining products with different degrees of polymerization (DP). Lipozyme 435 was the most efficient lipase to catalyze the transesterification reaction. HPLC and ESI-MS analysis proved the presence of a mixture of acylated products as a result of the chemical complexity of fructans in the A. tequilana. The ESI-MS spectra showed a molecular mass shift between 183 and 366g/mol for fructooligosaccharides with a DP lower than 6, which indicated the presence of Agave fructans that had been mono- and diacylated with lauric acid. The carbohydrate fatty acid esters (CFAE) obtained showed good emulsifying properties in W/O emulsions.

  18. Simultaneous determination of amino acids and carbohydrates in culture media of Clostridium thermocellum by valve-switching ion chromatography.

    PubMed

    Fa, Yun; Yang, Haiyan; Ji, Chengshuai; Cui, He; Zhu, Xinshu; Du, Juan; Gao, Jun

    2013-10-10

    An improved method for the simultaneous determination of 20 amino acids and 7 carbohydrates using one-valve switching after injection, ion chromatography, and integrated pulsed amperometric detection is proposed. The resolution of the amino acids and carbohydrates in the cation trap column was investigated. In addition, parameters including flow liquid type, flow rate, concentration, and valve-switch timing were optimized. The method is time-saving, effective, and accurate for the simultaneous separation of amino acids and carbohydrates, with a mean correlation coefficient of >0.99 and repeatability of 0.5-4.6% for eight replicates. The method was successfully applied in the analysis of amino acids and carbohydrates in aseptic media and in extracellular culture media of three phenotypes of Clostridium thermocellum.

  19. Selective Production of Formic Acid by Hydrothermal Alkaline Oxidation of Carbohydrates

    NASA Astrophysics Data System (ADS)

    Yun, J.; Li, G.; Enomoto, H.; Jin, F.

    2007-03-01

    Formic acid is a familiar product in hydrothermal oxidation of carbohydrates and is an important organic compound. In this study, the production of formic acid from the hydrothermal oxidation of glucose with and without the addition of alkali was investigated with temperature varying from 250 to 300°C, reaction time varying from 30 s to 240 s, and oxygen supply varying from 60 % to 140 %. Results showed that the highest yield of formic acid was only about 24 % in hydrothermal oxidation of glucose without the addition of alkali. It is very interest that the oxidation of glucose with the addition of alkali showed a high selective and effective for the production of formic acid. An excellent formic acid yield of about 74 % was achieved, which occurred at 250°C for 60 s with 120 % oxygen supply and the KOH concentration of 1.25 M.

  20. Diffusing colloidal probes of protein-carbohydrate interactions.

    PubMed

    Eichmann, Shannon L; Meric, Gulsum; Swavola, Julia C; Bevan, Michael A

    2013-02-19

    We present diffusing colloidal probe measurements of weak, multivalent, specific protein-polysaccharide interactions mediated by a competing monosaccharide. Specifically, we used integrated evanescent wave and video microscopy methods to monitor the three-dimensional Brownian excursions of conconavilin A (ConA) decorated colloids interacting with dextran-functionalized surfaces in the presence of glucose. Particle trajectories were interpreted as binding lifetime histograms, binding isotherms, and potentials of mean force. Binding lifetimes and isotherms showed clear trends of decreasing ConA-dextran-specific binding with increasing glucose concentration, consistent with expectations. Net potentials were accurately captured by superposition of a short-range, glucose-independent ConA-dextran repulsion and a longer-range, glucose-dependent dextran bridging attraction modeled as a harmonic potential. For glucose concentrations greater than 100 mM, the net ConA-dextran potential was found to have only a nonspecific repulsion, similar to that of bovine serum albumin (BSA) decorated colloids over dextran determined in control experiments. Our results demonstrate the first use of optical microscopy methods to quantify the connections between potentials of mean force and the binding behavior of ConA-decorated colloids on dextran-functionalized surfaces.

  1. The nutrient composition of European ready meals: protein, fat, total carbohydrates and energy.

    PubMed

    Kanzler, Sonja; Manschein, Martin; Lammer, Guido; Wagner, Karl-Heinz

    2015-04-01

    Despite the increasing social importance of ready meals, only few studies have been conducted on their nutrient composition. Therefore, 32 chilled, frozen and heat-treated ready meals (only main dishes) from the continental European market were analysed for protein, fat, total carbohydrate and energy. Half of the meals were nutritionally imbalanced by providing elevated fat (>30% of energy) and low carbohydrate levels (<50% of energy). Protein was generally above recommendations and ranged from 8.0 to 47.2g per serving. The inter-package variation was high, reaching 19.04 ± 2.90 g/package for fat. After proposing understandable guidelines to improve nutritional quality for the food industry, seven "nutritionally optimised" ready meals were created at the European level and analysed, however success was limited. If product labelling is to be useful for consumers, our results also indicate a need for better quality control to reduce the differences between content and labelling.

  2. Patterns of organic acids exuded by pioneering fungi from a glacier forefield are affected by carbohydrate sources

    NASA Astrophysics Data System (ADS)

    Brunner, Ivano; Goren, Asena; Schlumpf, Alessandro

    2014-01-01

    Bare soils in the area of retreating glaciers are ideal environments to study the role of microorganisms in the early soil formation and in processes of mineral weathering. The aim of our study was to investigate whether the source of carbohydrate would influence the patterns of organic acids exuded by fungal species. Three pioneering fungus species, isolated from fine granitic sediments in front of the Damma glacier from the central Swiss Alps, have previously been found to have the capability to exude organic acids and dissolve granite powder. In batch experiments, various carbohydrates, including glucose, cellulose, pectin, pollen, and cell remnants of cyanobacteria, fungi, and algae, were applied as carbohydrate sources and the patterns of exuded organic acids recorded. The results showed that two fungi, the zygomycete fungus Mucor hiemalis and the ascomycete fungus Penicillium chrysogenum, released a significantly higher amount of organic acids in dependence on specific carbohydrate sources. Pollen and algae as carbohydrate sources triggered significantly the exudation of malate in M. hiemalis, and pollen and cellulose that of oxalate in P. chrysogenum. We conclude that the occurrence of complex carbohydrate sources in nutrient-deficient deglaciated soils may positively influence the exudation of organic acids of fungi. In particular, pollen and remnants of other microorganisms can trigger the exudation of organic acids of fungi in order to promote the weathering of minerals and to make nutrients available that would otherwise be trapped in that cryospheric environment.

  3. Consequences of exchanging carbohydrates for proteins in the cholesterol metabolism of mice fed a high-fat diet.

    PubMed

    Raymond, Frédéric; Wang, Long; Moser, Mireille; Metairon, Sylviane; Mansourian, Robert; Zwahlen, Marie-Camille; Kussmann, Martin; Fuerholz, Andreas; Macé, Katherine; Chou, Chieh Jason

    2012-01-01

    Consumption of low-carbohydrate, high-protein, high-fat diets lead to rapid weight loss but the cardioprotective effects of these diets have been questioned. We examined the impact of high-protein and high-fat diets on cholesterol metabolism by comparing the plasma cholesterol and the expression of cholesterol biosynthesis genes in the liver of mice fed a high-fat (HF) diet that has a high (H) or a low (L) protein-to-carbohydrate (P/C) ratio. H-P/C-HF feeding, compared with L-P/C-HF feeding, decreased plasma total cholesterol and increased HDL cholesterol concentrations at 4-wk. Interestingly, the expression of genes involved in hepatic steroid biosynthesis responded to an increased dietary P/C ratio by first down-regulation (2-d) followed by later up-regulation at 4-wk, and the temporal gene expression patterns were connected to the putative activity of SREBF1 and 2. In contrast, Cyp7a1, the gene responsible for the conversion of cholesterol to bile acids, was consistently up-regulated in the H-P/C-HF liver regardless of feeding duration. Over expression of Cyp7a1 after 2-d and 4-wk H-P/C-HF feeding was connected to two unique sets of transcription regulators. At both time points, up-regulation of the Cyp7a1 gene could be explained by enhanced activations and reduced suppressions of multiple transcription regulators. In conclusion, we demonstrated that the hypocholesterolemic effect of H-P/C-HF feeding coincided with orchestrated changes of gene expressions in lipid metabolic pathways in the liver of mice. Based on these results, we hypothesize that the cholesterol lowering effect of high-protein feeding is associated with enhanced bile acid production but clinical validation is warranted. (246 words).

  4. Decreased rate of protein synthesis, caspase-3 activity, and ubiquitin-proteasome proteolysis in soleus muscles from growing rats fed a low-protein, high-carbohydrate diet.

    PubMed

    Batistela, Emanuele; Pereira, Mayara Peron; Siqueira, Juliany Torres; Paula-Gomes, Silvia; Zanon, Neusa Maria; Oliveira, Eduardo Brandt; Navegantes, Luiz Carlos Carvalho; Kettelhut, Isis C; Andrade, Claudia Marlise Balbinotti; Kawashita, Nair Honda; Baviera, Amanda Martins

    2014-06-01

    The aim of this study was to investigate the changes in the rates of both protein synthesis and breakdown, and the activation of intracellular effectors that control these processes in soleus muscles from growing rats fed a low-protein, high-carbohydrate (LPHC) diet for 15 days. The mass and the protein content, as well as the rate of protein synthesis, were decreased in the soleus from LPHC-fed rats. The availability of amino acids was diminished, since the levels of various essential amino acids were decreased in the plasma of LPHC-fed rats. Overall rate of proteolysis was also decreased, explained by reductions in the mRNA levels of atrogin-1 and MuRF-1, ubiquitin conjugates, proteasome activity, and in the activity of caspase-3. Soleus muscles from LPHC-fed rats showed increased insulin sensitivity, with increased levels of insulin receptor and phosphorylation levels of AKT, which probably explains the inhibition of both the caspase-3 activity and the ubiquitin-proteasome system. The fall of muscle proteolysis seems to represent an adaptive response that contributes to spare proteins in a condition of diminished availability of dietary amino acids. Furthermore, the decreased rate of protein synthesis may be the driving factor to the lower muscle mass gain in growing rats fed the LPHC diet.

  5. Influence of process variables on essential oil microcapsule properties by carbohydrate polymer-protein blends.

    PubMed

    Banerjee, Subham; Chattopadhyay, Pronobesh; Ghosh, Animesh; Goyary, Danswrang; Karmakar, Sanjeev; Veer, Vijay

    2013-04-01

    Carbohydrate polymer-protein blends Zanthoxylum limonella oil (ZLO) loaded microcapsules were prepared by multiple emulsion solvent evaporation technology and the influence of various processing variables on the properties of ZLO loaded microcapsules were examined systematically. It was found that the internal aqueous alginate phase volume, external aqueous gelatin phase volume and concentration of surfactant in external aqueous gelatin phase have a significant influence on microcapsules properties. The essential oil-loaded microcapsules were smooth and spherical in shape as revealed by scanning electron micrograph. Results of Fourier transform infrared (FTIR) spectroscopy indicated stable character and showed the absence of chemical interaction between the microencapsulated oil and carbohydrate polymer-protein blends. Differential scanning calorimetry (DSC) study revealed the antioxidant nature of ZLO in the microcapsules. The release rate of ZLO loaded microcapsules was analyzed by UV-vis spectrophotometer. 83.80% of oil encapsulation efficiency was obtained depending upon the processing variables. Thus, proper control of the processing variables involved in this technology could allow effective incorporation of essential oil into the core of the carbohydrate polymer-protein blends matrix.

  6. Comparison of Weight-Loss Diets with Different Compositions of Fat, Protein, and Carbohydrates

    PubMed Central

    Sacks, Frank M.; Bray, George A.; Carey, Vincent J.; Smith, Steven R.; Ryan, Donna H.; Anton, Stephen D.; McManus, Katherine; Champagne, Catherine M.; Bishop, Louise M.; Laranjo, Nancy; Leboff, Meryl S.; Rood, Jennifer C.; de Jonge, Lilian; Greenway, Frank L.; Loria, Catherine M.; Obarzanek, Eva; Williamson, Donald A.

    2009-01-01

    BACKGROUND The possible advantage for weight loss of a diet that emphasizes protein, fat, or carbohydrates has not been established, and there are few studies that extend beyond 1 year. METHODS We randomly assigned 811 overweight adults to one of four diets; the targeted percentages of energy derived from fat, protein, and carbohydrates in the four diets were 20, 15, and 65%; 20, 25, and 55%; 40, 15, and 45%; and 40, 25, and 35%. The diets consisted of similar foods and met guidelines for cardiovascular health. The participants were offered group and individual instructional sessions for 2 years. The primary outcome was the change in body weight after 2 years in two-by-two factorial comparisons of low fat versus high fat and average protein versus high protein and in the comparison of highest and lowest carbohydrate content. RESULTS At 6 months, participants assigned to each diet had lost an average of 6 kg, which represented 7% of their initial weight; they began to regain weight after 12 months. By 2 years, weight loss remained similar in those who were assigned to a diet with 15% protein and those assigned to a diet with 25% protein (3.0 and 3.6 kg, respectively); in those assigned to a diet with 20% fat and those assigned to a diet with 40% fat (3.3 kg for both groups); and in those assigned to a diet with 65% carbohydrates and those assigned to a diet with 35% carbohydrates (2.9 and 3.4 kg, respectively) (P>0.20 for all comparisons). Among the 80% of participants who completed the trial, the average weight loss was 4 kg; 14 to 15% of the participants had a reduction of at least 10% of their initial body weight. Satiety, hunger, satisfaction with the diet, and attendance at group sessions were similar for all diets; attendance was strongly associated with weight loss (0.2 kg per session attended). The diets improved lipid-related risk factors and fasting insulin levels. CONCLUSIONS Reduced-calorie diets result in clinically meaningful weight loss regardless of

  7. Conversion of cassava starch to biomass, carbohydrates, and acids by Aspergillus niger.

    PubMed

    Tan, K H; Ferguson, L B; Carlton, C

    1984-01-01

    The filamentous fungus, Aspergillus niger, efficiently converted cassava polysaccharides to mycelial mass, simple sugars, and acids during the course of its growth. A typical 70-ml culture broth containing 2% cassava polysaccharides yielded 0.38 g dry mycelial mass, 1.14 mmol reducing sugars, and 1.17 meq acids at the end of 42 h. About 70% of the initial total carbohydrate in the medium was degraded during the same period. The sugars and acids in the culture broths were analyzed by HPLC on a single Aminex HPX-87 column at 55 degrees C, using 0.013 N H2SO4 as the eluting solvent. Cassava polysaccharides were degraded to oligosaccharides, maltotriose, maltose, and glucose beyond the 20-h growth periods, with maltotriose emerging as the major simple sugar. The appearance of citric, malic, gluconic, succinic, and fumaric acids accounted mostly for the decreasing pH in the growth media. Formation of carbohydrate species in the culture broths was closely related to the biosynthesis and secretion of several carbohydrases by A. niger. The extracellular carbohydrases were separated and identified by chromatofocusing and polyacrylamide gel electrophoresis to be amyloglucosidase (EC 3.1.2.3), alpha-amylase (EC 3.2.1.1), and alpha-glucosidase (EC 3.2.1.20), respectively.

  8. Formation of aromatic compounds from carbohydrates. X reaction of xylose, glucose, and glucuronic acid in acidic solution at 300C

    SciTech Connect

    Theander, O.; Nelson, D.A.; Hallen, R.T.

    1987-04-01

    For several years our respective groups have investigated the formation of aromatic compounds from carbohydrates in aqueous solution at various pH-values under reflux or hydrothermolytic conditions. For instance, previous papers in this series concerned the degradation of hexoses, pentoses, erythrose, dihydroxyacetone, and hexuronic acids to phenolic and enolic components. Of particular interest were the isolation and identification of catechols, an acetophenone, and chromones from pentoses and hexuronic acids at pH 4.5. The formation of these compounds, as well as reductic acid, was found to be more pronounced than that of 2-furaldehyde under acidic conditions. The aromatic precursors of 3 and 4 were also isolated from these reaction mixtures. This is in contrast to the high yields of 2 obtained from pentoses and hexuronic acids at very low pH.

  9. Verification of protein sparing by feeding carbohydrate to common carp Cyprinus carpio

    NASA Astrophysics Data System (ADS)

    Cheng, Zhenyan; Li, Jinghui; Zhang, Baolong; Fang, Zhenzhen; Sun, Jinhui; Bai, Dongqing; Sun, Jinsheng; Qiao, Xiuting

    2016-06-01

    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 diff erent 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 diff erences in growth performance of fish fed the diets with diff erent protein and corn starch levels, but body composition and glucose metabolic enzyme activity of carp were significantly aff ected by the diff erent diets (P<0.05). Weight gain, specific growth rate, and the feed conversion ratio were not diff erent in fish fed the diff erent dietary treatments. Protein efficiency ratio increased significantly as corn starch level increased (P<0.05). Whole-body crude lipid composition increased with increasing dietary corn starch level (P<0.05). Glucokinase (GK), hexokinase, and pyruvate kinase (PK) activities increased significantly with increasing dietary corn starch level (P<0.05), whereas glucose-6-phosphate (G6Pase) activity decreased with increasing dietary corn starch level (P<0.05). GK gene expression was significantly higher in fish fed the high-corn starch diet than those fed the low-corn starch diet (P<0.05). G6pase gene expression tended to decrease with increasing starch level (P>0.05). In summary, the results indicate a protein-sparing effect by substituting carbohydrate in the diet of common carp.

  10. PROCARB: A Database of Known and Modelled Carbohydrate-Binding Protein Structures with Sequence-Based Prediction Tools

    PubMed Central

    Malik, Adeel; Firoz, Ahmad; Jha, Vivekanand; Ahmad, Shandar

    2010-01-01

    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. PMID:20671979

  11. L: (+)-Lactic acid production from non-food carbohydrates by thermotolerant Bacillus coagulans.

    PubMed

    Ou, Mark S; Ingram, Lonnie O; Shanmugam, K T

    2011-05-01

    Lactic acid is used as an additive in foods, pharmaceuticals, and cosmetics, and is also an industrial chemical. Optically pure lactic acid is increasingly used as a renewable bio-based product to replace petroleum-based plastics. However, current production of lactic acid depends on carbohydrate feedstocks that have alternate uses as foods. The use of non-food feedstocks by current commercial biocatalysts is limited by inefficient pathways for pentose utilization. B. coagulans strain 36D1 is a thermotolerant bacterium that can grow and efficiently ferment pentoses using the pentose-phosphate pathway and all other sugar constituents of lignocellulosic biomass at 50°C and pH 5.0, conditions that also favor simultaneous enzymatic saccharification and fermentation (SSF) of cellulose. Using this bacterial biocatalyst, high levels (150-180 g l(-1)) of lactic acid were produced from xylose and glucose with minimal by-products in mineral salts medium. In a fed-batch SSF of crystalline cellulose with fungal enzymes and B. coagulans, lactic acid titer was 80 g l(-1) and the yield was close to 80%. These results demonstrate that B. coagulans can effectively ferment non-food carbohydrates from lignocellulose to L: (+)-lactic acid at sufficient concentrations for commercial application. The high temperature fermentation of pentoses and hexoses to lactic acid by B. coagulans has these additional advantages: reduction in cellulase loading in SSF of cellulose with a decrease in enzyme cost in the process and a reduction in contamination of large-scale fermentations. PMID:20694852

  12. Glycemic Response of a Carbohydrate-Protein Bar with Ewe-Goat Whey

    PubMed Central

    Manthou, Eirini; Kanaki, Maria; Georgakouli, Kalliopi; Deli, Chariklia K.; Kouretas, Dimitrios; Koutedakis, Yiannis; Jamurtas, Athanasios Z.

    2014-01-01

    In this study we examined the glycaemic index (GI) and glycaemic load (GL) of a functional food product, which contains ewe-goat whey protein and carbohydrates in a 1:1 ratio. Nine healthy volunteers, (age, 23.3 ± 3.9 years; body mass index, 24.2 ± 4.1 kg·m2; body fat %, 18.6 ± 10.0) randomly consumed either a reference food or amount of the test food both with equal carbohydrate content in two visits. In each visit, seven blood samples were collected; the first sample after an overnight fast and the remaining six at 15, 30, 45, 60, 90 and 120 min after the beginning of food consumption. Plasma glucose concentration was measured and the GI was determined by calculation of the incremental area under the curve. The GL was calculated using the equation: test food GI/100 g available carbohydrates per test food serving. The GI of the test food was found to be 5.18 ± 3.27, while the GL of one test food serving was 1.09 ± 0.68. These results indicate that the tested product can be classified as a low GI (<55) and low GL (<10) food. Given the health benefits of low glycaemic response foods and whey protein consumption, the tested food could potentially promote health beyond basic nutrition. PMID:24926525

  13. Dietary Proportions of Carbohydrates, Fat, and Protein and Risk of Oesophageal Cancer by Histological Type

    PubMed Central

    Lagergren, Katarina; Lindam, Anna; Lagergren, Jesper

    2013-01-01

    Background Dietary habits influence the risk of cancer of the oesophagus and oesophago-gastric junction, but the role of proportions of the main dietary macronutrients carbohydrates, fats and proteins is uncertain. Methods Data was derived from a nationwide Swedish population-based case-control study conducted in 1995–1997, in which case ascertainment was rapid, and all cases were uniformly classified. Information on the subjects' history of dietary intake was collected in personal interviews. Odds ratios (ORs) and 95% confidence intervals (CIs) were calculated using logistic regression, with adjustment for potentially confounding factors. Results Included were 189 oesophageal adenocarcinomas, 262 oesophago-gastric adenocarcinomas, 167 oesophageal squamous cell carcinomas, and 820 control subjects. Regarding oesophageal or oesophago-gastric junctional adenocarcinoma, a high dietary proportion of carbohydrates decreased the risk (OR 0.50, CI 0.34–0.73), and a high portion of fat increased the risk (OR 1.96, CI 1.34–2.87), while a high proportion of protein did not influence the risk (OR 1. 08, 95% CI 0.75–1.56). Regarding oesophageal squamous cell carcinoma, the single macronutrients did not influence the risk statistically significantly. Conclusions A diet with a low proportion of carbohydrates and a high proportion of fat might increase the risk of oesophageal adenocarcinoma. PMID:23349988

  14. Monomeric carbohydrates production from olive tree pruning biomass: modeling of dilute acid hydrolysis.

    PubMed

    Puentes, Juan G; Mateo, Soledad; Fonseca, Bruno G; Roberto, Inês C; Sánchez, Sebastián; Moya, Alberto J

    2013-12-01

    Statistical modeling and optimization of dilute sulfuric acid hydrolysis of olive tree pruning biomass has been performed using response surface methodology. Central composite rotatable design was applied to assess the effect of acid concentration, reaction time and temperature on efficiency and selectivity of hemicellulosic monomeric carbohydrates to d-xylose. Second-order polynomial model was fitted to experimental data to find the optimum reaction conditions by multiple regression analysis. The monomeric d-xylose recovery 85% (as predicted by the model) was achieved under optimized hydrolysis conditions (1.27% acid concentration, 96.5°C and 138 min), confirming the high validity of the developed model. The content of d-glucose (8.3%) and monosaccharide degradation products (0.1% furfural and 0.04% 5-hydroxymethylfurfural) provided a high quality subtract, ready for subsequent biochemical conversion to value-added products.

  15. Monomeric carbohydrates production from olive tree pruning biomass: modeling of dilute acid hydrolysis.

    PubMed

    Puentes, Juan G; Mateo, Soledad; Fonseca, Bruno G; Roberto, Inês C; Sánchez, Sebastián; Moya, Alberto J

    2013-12-01

    Statistical modeling and optimization of dilute sulfuric acid hydrolysis of olive tree pruning biomass has been performed using response surface methodology. Central composite rotatable design was applied to assess the effect of acid concentration, reaction time and temperature on efficiency and selectivity of hemicellulosic monomeric carbohydrates to d-xylose. Second-order polynomial model was fitted to experimental data to find the optimum reaction conditions by multiple regression analysis. The monomeric d-xylose recovery 85% (as predicted by the model) was achieved under optimized hydrolysis conditions (1.27% acid concentration, 96.5°C and 138 min), confirming the high validity of the developed model. The content of d-glucose (8.3%) and monosaccharide degradation products (0.1% furfural and 0.04% 5-hydroxymethylfurfural) provided a high quality subtract, ready for subsequent biochemical conversion to value-added products. PMID:24096282

  16. Association of protein structure, protein and carbohydrate subfractions with bioenergy profiles and biodegradation functions in modeled forage

    NASA Astrophysics Data System (ADS)

    Ji, Cuiying; Zhang, Xuewei; Yu, Peiqiang

    2016-03-01

    The objectives of this study were to detect unique aspects and association of forage protein inherent structure, biological compounds, protein and carbohydrate subfractions, bioenergy profiles, and biodegradation features. In this study, common available alfalfa hay from two different sourced-origins (FSO vs. CSO) was used as a modeled forage for inherent structure profile, bioenergy, biodegradation and their association between their structure and bio-functions. The molecular spectral profiles were determined using non-invasive molecular spectroscopy. The parameters included: protein structure amide I group, amide II group and their ratios; protein subfractions (PA1, PA2, PB1, PB2, PC); carbohydrate fractions (CA1, CA2, CA3, CA4, CB1, CB2, CC); biodegradable and undegradable fractions of protein (RDPA2, RDPB1, RDPB2, RDP; RUPA2 RUPB1, RUPB2, RUPC, RUP); biodegradable and undegradable fractions of carbohydrate (RDCA4, RDCB1, RDCB2, RDCB3, RDCHO; RUCA4, RUCB1; RUCB2; RUCB3 RUCC, RUCHO) and bioenergy profiles (tdNDF, tdFA, tdCP, tdNFC, TDN1 ×, DE3 ×, ME3 ×, NEL3 ×; NEm, NEg). The results show differences in protein and carbohydrate (CHO) subfractions in the moderately degradable true protein fraction (PB1: 502 vs. 420 g/kg CP, P = 0.09), slowly degraded true protein fraction (PB2: 45 vs. 96 g/kg CP, P = 0.02), moderately degradable CHO fraction (CB2: 283 vs. 223 g/kg CHO, P = 0.06) and slowly degraded CHO fraction (CB3: 369 vs. 408 g/kg CHO) between the two sourced origins. As to biodegradable (RD) fractions of protein and CHO in rumen, there were differences in RD of PB1 (417 vs. 349 g/kg CP, P = 0.09), RD of PB2 (29 vs. 62 g/kg CP, P = 0.02), RD of CB2 (251 vs. 198 g/kg DM, P = 0.06), RD of CB3 (236 vs. 261 g/kg CHO, P = 0.08). As to bioenergy profile, there were differences in total digestible nutrient (TDN: 551 vs. 537 g/kg DM, P = 0.06), and metabolic bioenergy (P = 0.095). As to protein molecular structure, there were differences in protein structure 1st

  17. Association of protein structure, protein and carbohydrate subfractions with bioenergy profiles and biodegradation functions in modeled forage.

    PubMed

    Ji, Cuiying; Zhang, Xuewei; Yu, Peiqiang

    2016-03-15

    The objectives of this study were to detect unique aspects and association of forage protein inherent structure, biological compounds, protein and carbohydrate subfractions, bioenergy profiles, and biodegradation features. In this study, common available alfalfa hay from two different sourced-origins (FSO vs. CSO) was used as a modeled forage for inherent structure profile, bioenergy, biodegradation and their association between their structure and bio-functions. The molecular spectral profiles were determined using non-invasive molecular spectroscopy. The parameters included: protein structure amide I group, amide II group and their ratios; protein subfractions (PA1, PA2, PB1, PB2, PC); carbohydrate fractions (CA1, CA2, CA3, CA4, CB1, CB2, CC); biodegradable and undegradable fractions of protein (RDPA2, RDPB1, RDPB2, RDP; RUPA2 RUPB1, RUPB2, RUPC, RUP); biodegradable and undegradable fractions of carbohydrate (RDCA4, RDCB1, RDCB2, RDCB3, RDCHO; RUCA4, RUCB1; RUCB2; RUCB3 RUCC, RUCHO) and bioenergy profiles (tdNDF, tdFA, tdCP, tdNFC, TDN1×, DE3×, ME3×, NEL3×; NEm, NEg). The results show differences in protein and carbohydrate (CHO) subfractions in the moderately degradable true protein fraction (PB1: 502 vs. 420 g/kg CP, P=0.09), slowly degraded true protein fraction (PB2: 45 vs. 96 g/kg CP, P=0.02), moderately degradable CHO fraction (CB2: 283 vs. 223 g/kg CHO, P=0.06) and slowly degraded CHO fraction (CB3: 369 vs. 408 g/kg CHO) between the two sourced origins. As to biodegradable (RD) fractions of protein and CHO in rumen, there were differences in RD of PB1 (417 vs. 349 g/kg CP, P=0.09), RD of PB2 (29 vs. 62 g/kg CP, P=0.02), RD of CB2 (251 vs. 198 g/kg DM, P=0.06), RD of CB3 (236 vs. 261 g/kg CHO, P=0.08). As to bioenergy profile, there were differences in total digestible nutrient (TDN: 551 vs. 537 g/kg DM, P=0.06), and metabolic bioenergy (P=0.095). As to protein molecular structure, there were differences in protein structure 1st and 2nd amide groups (P

  18. Amino acid and carbohydrate preferences in C57BL/6ByJ and 129P3/J mice

    PubMed Central

    Bachmanov, Alexander A.; Beauchamp, Gary K.

    2008-01-01

    Compared with mice from the 129P3/J (129) inbred strain, mice from the C57BL/6ByJ (B6) inbred strain have higher consumption of several sweet-tasting amino acids and carbohydrates. To examine the relative contribution of taste and nutritive properties in these strain differences, we measured responses of B6 and 129 mice to eight sweet and non-sweet amino acids and carbohydrates in two-bottle preference tests with water. Mice from the two strains did not differ in consumption of non-sweet L-valine and L-histidine. Compared with 129 mice, B6 mice had higher consumption and lower preference thresholds for sweet amino acids L-glutamine, L-alanine and L-threonine, monosaccharides glucose and fructose, and maltooligosaccharide. These data suggest that differences in gustatory responsiveness are an important factor underlying higher consumption of some amino acids and carbohydrates by B6 mice compared with 129 mice. It is likely that in B6 mice, higher sweet taste responsiveness results in increased consumption of sweet-tasting amino acids and sugars, and higher taste responsiveness to complex carbohydrates results in increased consumption of maltooligosaccharide. However, postingestive processes also influence nutrient consumption and may be responsible for higher intake of carbohydrates compared with sweet-tasting amino acids. Results of this study set the stage for genetic analysis of differences between B6 and 129 mice in taste responsiveness and macronutrient consumption. PMID:17764708

  19. Tracking the oxidative kinetics of carbohydrates, amino acids and fatty acids in the house sparrow using exhaled 13CO2.

    PubMed

    McCue, M D; Sivan, O; McWilliams, S R; Pinshow, B

    2010-03-01

    Clinicians commonly measure the (13)CO(2) in exhaled breath samples following administration of a metabolic tracer (breath testing) to diagnose certain infections and metabolic disorders. We believe that breath testing can become a powerful tool to investigate novel questions about the influence of ecological and physiological factors on the oxidative fates of exogenous nutrients. Here we examined several predictions regarding the oxidative kinetics of specific carbohydrates, amino acids and fatty acids in a dietary generalist, the house sparrow (Passer domesticus). After administering postprandial birds with 20 mg of one of seven (13)C-labeled tracers, we measured rates of (13)CO(2) production every 15 min over 2 h. We found that sparrows oxidized exogenous amino acids far more rapidly than carbohydrates or fatty acids, and that different tracers belonging to the same class of physiological fuels had unique oxidative kinetics. Glycine had a mean maximum rate of oxidation (2021 nmol min(-1)) that was significantly higher than that of leucine (351 nmol min(-1)), supporting our prediction that nonessential amino acids are oxidized more rapidly than essential amino acids. Exogenous glucose and fructose were oxidized to a similar extent (5.9% of dose), but the time required to reach maximum rates of oxidation was longer for fructose. The maximum rates of oxidation were significantly higher when exogenous glucose was administered as an aqueous solution (122 nmol min(-1)), rather than as an oil suspension (93 nmol min(-1)), supporting our prediction that exogenous lipids negatively influence rates of exogenous glucose oxidation. Dietary fatty acids had the lowest maximum rates of oxidation (2-6 nmol min(-1)), and differed significantly in the extent to which each was oxidized, with 0.73%, 0.63% and 0.21% of palmitic, oleic and stearic acid tracers oxidized, respectively.

  20. Changes of Mouse Gut Microbiota Diversity and Composition by Modulating Dietary Protein and Carbohydrate Contents: A Pilot Study

    PubMed Central

    Kim, Eunjung; Kim, Dan-Bi; Park, Jae-Yong

    2016-01-01

    Dietary proteins influence colorectal cancer (CRC) risk, depending on their quantity and quality. Here, using pyrosequencing, we compared the fecal microbiota composition in Balb/c mice fed either a normal protein/carbohydrate diet (ND, 20% casein and 68% carbohydrate) or a high-protein/low-carbohydrate diet (HPLCD, 30% casein and 57% carbohydrate). The results showed that HPLCD feeding for 2 weeks reduced the diversity and altered the composition of the microbiota compared with the ND mice, which included a decrease in the proportion of the family Lachnospiraceae and Ruminococcaceae and increases in the proportions of the genus Bacteroides and Parabacteroides, especially the species EF09600_s and EF604598_s. Similar changes were reported in patients with inflammatory bowel disease, and in mouse models of CRC and colitis, respectively. This suggests that HPLCD may lead to a deleterious luminal environment and may have adverse effects on the intestinal health of individuals consuming such a diet. PMID:27069907

  1. Transformation of cellulose and its derived carbohydrates into formic and lactic acids catalyzed by vanadyl cations.

    PubMed

    Tang, Zhenchen; Deng, Weiping; Wang, Yanliang; Zhu, Enze; Wan, Xiaoyue; Zhang, Qinghong; Wang, Ye

    2014-06-01

    The transformation of cellulose or cellulose-derived carbohydrates into platform chemicals is the key to establish biomass-based sustainable chemical processes. The systems able to catalyze the conversion of cellulose into key chemicals in water without the consumption of hydrogen are limited. We report that simple vanadyl (VO(2+)) cations catalyze the conversions of cellulose and its monomer, glucose, into lactic acid and formic acid in water. We have discovered an interesting shift of the major product from formic acid to lactic acid on switching the reaction atmosphere from oxygen to nitrogen. Our studies suggest that VO(2+) catalyzes the isomerization of glucose to fructose, the retro-aldol fragmentation of fructose to two trioses, and the isomerization of trioses, which leads to the formation of lactic acid under anaerobic conditions. The oxidative cleavage of C-C bonds in the intermediates caused by the redox conversion of VO2(+)/VO(2+) under aerobic conditions results in formic acid and CO2. We demonstrate that the addition of an alcohol suppresses the formation of CO2 and enhances the formic acid yield significantly to 70-75 %.

  2. Transformation of cellulose and its derived carbohydrates into formic and lactic acids catalyzed by vanadyl cations.

    PubMed

    Tang, Zhenchen; Deng, Weiping; Wang, Yanliang; Zhu, Enze; Wan, Xiaoyue; Zhang, Qinghong; Wang, Ye

    2014-06-01

    The transformation of cellulose or cellulose-derived carbohydrates into platform chemicals is the key to establish biomass-based sustainable chemical processes. The systems able to catalyze the conversion of cellulose into key chemicals in water without the consumption of hydrogen are limited. We report that simple vanadyl (VO(2+)) cations catalyze the conversions of cellulose and its monomer, glucose, into lactic acid and formic acid in water. We have discovered an interesting shift of the major product from formic acid to lactic acid on switching the reaction atmosphere from oxygen to nitrogen. Our studies suggest that VO(2+) catalyzes the isomerization of glucose to fructose, the retro-aldol fragmentation of fructose to two trioses, and the isomerization of trioses, which leads to the formation of lactic acid under anaerobic conditions. The oxidative cleavage of C-C bonds in the intermediates caused by the redox conversion of VO2(+)/VO(2+) under aerobic conditions results in formic acid and CO2. We demonstrate that the addition of an alcohol suppresses the formation of CO2 and enhances the formic acid yield significantly to 70-75 %. PMID:24798653

  3. Catalytic conversion of carbohydrates to 5-hydroxymethylfurfural from the waste liquid of acid hydrolysis NCC.

    PubMed

    Sun, Yonghui; Liu, Pengtao; Liu, Zhong

    2016-05-20

    The principal goal of this work was to reuse the carbohydrates and recycle sulfuric acid in the waste liquid of acid hydrolysis nanocrystalline cellulose (NCC). Therefore, in this work, the optimizations of further hydrolysis of waste liquid of acid hydrolysis NCC and catalytic conversion of L4 to 5-hydroxymethylfurfural (5-HMF) were studied. Sulfuric acid was separated by spiral wound diffusion dialysis (SWDD). The results revealed that cellulose can be hydrolyze to glucose absolutely under the condition of temperature 35 °C, 3 h, and sulfuric acid's concentration 62 wt%. And 78.3% sulfuric acid was recovered by SWDD. The yield of 5-HMF was highest in aqueous solution under the optimal condition was as follows, temperature 160 °C, 3 h, and sulfuric acid's concentration 12 wt%. Then the effect of biphasic solvent systems catalytic conversion and inorganic salt as additives were still examined. The results showed that both of them contributed to prepare 5-HMF. The yield and selectivity of 5-HMF was up to 21.0% and 31.4%, respectively.

  4. The impact of low-protein high-carbohydrate diets on aging and lifespan.

    PubMed

    Le Couteur, David G; Solon-Biet, Samantha; Cogger, Victoria C; Mitchell, Sarah J; Senior, Alistair; de Cabo, Rafael; Raubenheimer, David; Simpson, Stephen J

    2016-03-01

    Most research on nutritional effects on aging has focussed on the impact of manipulating single dietary factors such as total calorie intake or each of the macronutrients individually. More recent studies using a nutritional geometric approach called the Geometric Framework have facilitated an understanding of how aging is influenced across a landscape of diets that vary orthogonally in macronutrient and total energy content. Such studies have been performed using ad libitum feeding regimes, thus taking into account compensatory feeding responses that are inevitable in a non-constrained environment. Geometric Framework studies on insects and mice have revealed that diets low in protein and high in carbohydrates generate longest lifespans in ad libitum-fed animals while low total energy intake (caloric restriction by dietary dilution) has minimal effect. These conclusions are supported indirectly by observational studies in humans and a heterogeneous group of other types of interventional studies in insects and rodents. Due to compensatory feeding for protein dilution, low-protein, high-carbohydrate diets are often associated with increased food intake and body fat, a phenomenon called protein leverage. This could potentially be mitigated by supplementing these diets with interventions that influence body weight through physical activity and ambient temperature.

  5. Modification of soy protein hydrolysates by Maillard reaction: Effects of carbohydrate chain length on structural and interfacial properties.

    PubMed

    Li, Weiwei; Zhao, Haibo; He, Zhiyong; Zeng, Maomao; Qin, Fang; Chen, Jie

    2016-02-01

    This study investigated the effects of carbohydrate chain length on the structural and interfacial properties of the Maillard reaction conjugates of soy protein hydrolysates (Mw>30 kDa). The covalent attachment of sugars to soy peptides was confirmed by amino acid analysis and examination of the Fourier-transform infrared spectra. The results suggested that the emulsion stability of the conjugates increased as the length of the carbohydrate chains increased. The surface activity measurement revealed that the soy peptide-dextran conjugates were closely packed and that each molecule occupied a small area of the interface. It was further confirmed that the soy peptide-dextran conjugates formed a thick adsorbed layer at the oil-water interface, as observed in the confocal laser scanning micrographs. The interfacial layer of soy peptides was rheologically complex with broad linear viscoelastic region and strong elastic modulus, and the soy peptide-dextran conjugates might form multilayer adsorption at the interface. This study suggested that the improved surface properties of the soy peptide-dextran conjugates were a result of the strong membrane formed by the closely packed molecular and multilayer adsorption at the interface, which provided steric hindrance to flocculation. PMID:26655794

  6. Mcy protein, a potential antidiabetic agent: evaluation of carbohydrate metabolic enzymes and antioxidant status.

    PubMed

    Marella, Saritha; Maddirela, Dilip Rajasekhar; Kumar, E G T V; Tilak, Thandaiah Krishna; Badri, Kameswara Rao; Chippada, Apparao

    2016-05-01

    The objective of the present study is to elucidate the long-term effects of anti-hyperglycemic active principle, Mcy protein (MCP), isolated from the fruits of Momordica cymbalaria on carbohydrate metabolism and oxidative stress in experimental diabetic rats. We used streptozotocin induced diabetic rats for the current studies. Our studies showed that MCP (2.5mg/kg.b.w) treatment significantly normalized the deranged activities of critical carbohydrate metabolizing enzymes, hexokinase, glucose-6-phosphate dehydrogenase, glucose-6-phosphatase and fructose-1,6-bis phosphatase. In addition MCP showed inhibitory activity on α-glucosidase and aldose reductase enzymes in in vitro assays. Further MCP treatment improved the antioxidant defensive mechanism by preventing deleterious oxidative products of cellular metabolism, which initiates the lipid peroxidation and by normalizing the antioxidant enzyme (catalase, superoxide dismutase, glutathione peroxidase) activities. Additional structural studies using circular dichroism spectroscopy indicate that MCP contains majorly α-helix. Our findings suggest MCP regulates blood glucose and better manage diabetes mellitus associated complications by regulating carbohydrate metabolism and by protecting from the deleterious effects of oxidative stress. PMID:26826289

  7. Chemotactic behavior of deep subsurface bacteria toward carbohydrates, amino acids and a chlorinated alkene

    SciTech Connect

    Lopez de Victoria, G. . Dept. of Biology)

    1989-02-01

    The chemotactic behavior of deep terrestrial subsurface bacteria toward amino acids, carbohydrates and trichloroethylene was assayed using a modification of the capillary method and bacterial enumeration by acridine orange direct counts. Eleven isolates of bacteria isolated from six different geological formations were investigated. A bimodal response rather than an absolute positive or negative response was observed in most assays. Most of the isolates were positively chemotactic to low concentrations of substrates and were repelled by high concentrations of the same substrate. However, this was not the case for trichloroethylene (TCE) which was mostly an attractant and elicited the highest responses in all the isolates when compared with amino acids and carbohydrates. The movement rates of these isolates in aseptic subsurface sediments in the absence and presence of TCE were also determined using a laboratory model. All of the isolates showed distinct response range, peak, and threshold concentrations when exposed to the same substrates suggesting that they are possibly different species as has been inferred from DNA homology studies. 101 refs., 4 figs., 57 tabs.

  8. Nanoparticle-enhanced fluorescence emission for non-separation assays of carbohydrates using a boronic acid-alizarin complex.

    PubMed

    Li, Qianjin; Kamra, Tripta; Ye, Lei

    2016-03-01

    Addition of crosslinked polymer nanoparticles into a solution of a 3-nitrophenylboronic acid-alizarin complex leads to significant enhancement of fluorescence emission. Using the nanoparticle-enhanced boronic acid-alizarin system has improved greatly the sensitivity and extended the dynamic range of separation-free fluorescence assays for carbohydrates.

  9. Synthesis and Evaluation of Aryl Boronic Acids as Fluorescent Artificial Receptors for Biological Carbohydrates

    PubMed Central

    Craig, Sandra

    2011-01-01

    Carbohydrates in various forms play a vital role in numerous critical biological processes. The detection of such saccharides can give insight into the progression of such diseases such as cancer. Boronic acids react with 1,2 and 1,3 diols of saccharides in non-aqueous or basic aqueous media. Herein, we describe the design, synthesis and evaluation of three bisboronic acid fluorescent probes, each having about ten linear steps in its synthesis. Among these compounds that were evaluated, 9b was shown to selectively label HepG2, liver carcinoma cell line within a concentration range of 0.5–10 μM in comparison to COS-7, a normal fibroblast cell line. PMID:22177855

  10. Carbohydrate vs protein supplementation for recovery of neuromuscular function following prolonged load carriage

    PubMed Central

    2010-01-01

    Background This study examined the effect of carbohydrate and whey protein supplements on recovery of neuromuscular function after prolonged load carriage. Methods Ten male participants (body mass: 81.5 ± 10.5 kg, age: 28 ± 9 years, O2max: 55.0 ± 5.5 ml·kg-1·min-1) completed three treadmill walking tests (2 hr, 6.5 km·h-1), carrying a 25 kg backpack consuming 500 ml of either: (1) Placebo (flavoured water) [PLA], (2) 6.4% Carbohydrate Solution [CHO] or (3) 7.0% Whey Protein Solution [PRO]. For three days after load carriage, participants consumed two 500 ml supplement boluses. Muscle performance was measured before and at 0, 24, 48 and 72 h after load carriage, during voluntary and electrically stimulated contractions. Results Isometric knee extension force decreased immediately after load carriage with no difference between conditions. During recovery, isometric force returned to pre-exercise values at 48 h for CHO and PRO but at 72 h for PLA. Voluntary activation decreased immediately after load carriage and returned to pre-exercise values at 24 h in all conditions (P = 0.086). During recovery, there were no differences between conditions for the change in isokinetic peak torque. Following reductions immediately after load carriage, knee extensor and flexor peak torque (60°·s-1) recovered to pre-exercise values at 72 h. Trunk extensor and flexor peak torque (15°·s-1) recovered to pre-exercise values at 24 h (P = 0.091) and 48 h (P = 0.177), respectively. Conclusion Recovery of neuromuscular function after prolonged load carriage is improved with either carbohydrate or whey protein supplementation for isometric contractions but not for isokinetic contractions. PMID:20157419

  11. Evaluation of Selected Classical Force Fields for Alchemical Binding Free Energy Calculations of Protein-Carbohydrate Complexes.

    PubMed

    Mishra, Sushil K; Calabró, Gaetano; Loeffler, Hannes H; Michel, Julien; Koča, Jaroslav

    2015-07-14

    Protein-carbohydrate recognition is crucial in many vital biological processes including host-pathogen recognition, cell-signaling, and catalysis. Accordingly, computational prediction of protein-carbohydrate binding free energies is of enormous interest for drug design. However, the accuracy of current force fields (FFs) for predicting binding free energies of protein-carbohydrate complexes is not well understood owing to technical challenges such as the highly polar nature of the complexes, anomerization, and conformational flexibility of carbohydrates. The present study evaluated the performance of alchemical predictions of binding free energies with the GAFF1.7/AM1-BCC and GLYCAM06j force fields for modeling protein-carbohydrate complexes. Mean unsigned errors of 1.1 ± 0.06 (GLYCAM06j) and 2.6 ± 0.08 (GAFF1.7/AM1-BCC) kcal·mol(-1) are achieved for a large data set of monosaccharide ligands for Ralstonia solanacearum lectin (RSL). The level of accuracy provided by GLYCAM06j is sufficient to discriminate potent, moderate, and weak binders, a goal that has been difficult to achieve through other scoring approaches. Accordingly, the protocols presented here could find useful applications in carbohydrate-based drug and vaccine developments. PMID:26575767

  12. Low protein-high carbohydrate diet induces alterations in the serum thyronine-binding proteins in the rat.

    PubMed

    Young, R A; Braverman, L E; Rajatanavin, R

    1982-05-01

    The serum T3 concentration was increased in 8-week-old lean Zucker rats fed a low protein-high carbohydrate diet for 2 weeks. This increase was secondary to the generation of a binding protein migrating in the postalbumin zone in polyacrylamide gel electrophoresis employing 125I-labeled T3 and is termed rat thyronine-binding globulin. The presence of this T3-binding protein in serum resulted in a marked decrease in the percent free T3 assessed by equilibrium dialysis and a normal free T3 concentration. An increase in the binding of T4 in the postalbumin zone was also observed, but no changes in the dialyzable fraction of T4 or the total and free T4 concentrations occurred. In contrast to these findings in lean Zucker rats fed the low protein-high carbohydrate diet, no change in the pattern of 125I-labeled T3 and T4 binding, the dialyzable fraction of T3 or T4, or total and free T3 or T4 concentrations were observed in the obese Zucker rats fed this diet. The present findings suggest that diet-induced alterations in thyroid hormone-binding proteins must be considered in the interpretation of data which involve alterations in total thyroid hormone concentrations in serum and their role in affecting tissue metabolism.

  13. Genetically Encoded Fragment-Based Discovery of Glycopeptide Ligands for Carbohydrate-Binding Proteins

    SciTech Connect

    Ng, Simon; Lin, Edith; Kitov, Pavel I.; Tjhung, Katrina F.; Gerlits, Oksana O.; Deng, Lu; Kasper, Brian; Sood, Amika; Paschal, Beth M.; Zhang, Ping; Ling, Chang-Chun; Klassen, John S.; Noren, Christopher J.; Mahal, Lara K.; Woods, Robert J.; Coates, Leighton; Derda, Ratmir

    2015-04-10

    Here we describe an approach to accelerate the search for competitive inhibitors for carbohydrate-recognition domains (CRDs). Genetically encoded fragment-based-discovery (GE-FBD) uses selection of phagedisplayed glycopeptides to dock a glycan fragment at the CRD and guide selection of Synergistic peptide motifs adjacent to the CRD. Starting from concanavalin A (ConA), a mannose (Man)-binding protein, as a bait, we narrowed a library of 108 glycopeptides to 86 leads that share a consensus motif, Man-WYD. Validation of synthetic leads yielded Man-WYDLF that exhibited 40 50-fold enhancement in affinity over methyl α-D-mannopyranoside (MeMan). Lectin array Suggested specificity: Man-WYD derivative bound only to 3 out of 17 proteins-ConA, LcH, and PSA-that bind to Man. An X-ray structure of ConA.:Man-WYD proved that the trimannoside core and Man-WYD exhibit identical CRD docking; but their extra-CRD binding modes are significantly. different. Still, they have comparable affinity and selectivity for various Man-binding proteins. The intriguing observation provides new insight into functional mimicry :of carbohydrates by peptide ligands. GE-FBD may provide an alternative to rapidly search for competitive inhibitors for lectins.

  14. Genetically Encoded Fragment-Based Discovery of Glycopeptide Ligands for Carbohydrate-Binding Proteins

    DOE PAGES

    Ng, Simon; Lin, Edith; Kitov, Pavel I.; Tjhung, Katrina F.; Gerlits, Oksana O.; Deng, Lu; Kasper, Brian; Sood, Amika; Paschal, Beth M.; Zhang, Ping; et al

    2015-04-10

    Here we describe an approach to accelerate the search for competitive inhibitors for carbohydrate-recognition domains (CRDs). Genetically encoded fragment-based-discovery (GE-FBD) uses selection of phagedisplayed glycopeptides to dock a glycan fragment at the CRD and guide selection of Synergistic peptide motifs adjacent to the CRD. Starting from concanavalin A (ConA), a mannose (Man)-binding protein, as a bait, we narrowed a library of 108 glycopeptides to 86 leads that share a consensus motif, Man-WYD. Validation of synthetic leads yielded Man-WYDLF that exhibited 40 50-fold enhancement in affinity over methyl α-D-mannopyranoside (MeMan). Lectin array Suggested specificity: Man-WYD derivative bound only to 3 outmore » of 17 proteins-ConA, LcH, and PSA-that bind to Man. An X-ray structure of ConA.:Man-WYD proved that the trimannoside core and Man-WYD exhibit identical CRD docking; but their extra-CRD binding modes are significantly. different. Still, they have comparable affinity and selectivity for various Man-binding proteins. The intriguing observation provides new insight into functional mimicry :of carbohydrates by peptide ligands. GE-FBD may provide an alternative to rapidly search for competitive inhibitors for lectins.« less

  15. Addition of glutamine to essential amino acids and carbohydrate does not enhance anabolism in young human males following exercise.

    PubMed

    Wilkinson, Sarah B; Kim, Paul L; Armstrong, David; Phillips, Stuart M

    2006-10-01

    We examined the effect of a post-exercise oral carbohydrate (CHO, 1 g.kg(-1).h(-1)) and essential amino acid (EAA, 9.25 g) solution containing glutamine (0.3 g/kg BW; GLN trial) versus an isoenergetic CHO-EAA solution without glutamine (control, CON trial) on muscle glycogen resynthesis and whole-body protein turnover following 90 min of cycling at 65% VO2 peak. Over the course of 3 h of recovery, muscle biopsies were taken to measure glycogen resynthesis and mixed muscle protein synthesis (MPS), by incorporation of [ring-2H5] phenylalanine. Infusion of [1-13C] leucine was used to measure whole-body protein turnover. Exercise resulted in a significant decrease in muscle glycogen (p < 0.05) with similar declines in each trial. Glycogen resynthesis following 3 h of recovery indicated no difference in total accumulation or rate of repletion. Leucine oxidation increased 2.5 fold (p < 0.05) during exercise, returned to resting levels immediately post-exercise,and was again elevated at 3 h post-exercise (p < 0.05). Leucine flux, an index of whole-body protein breakdown rate, was reduced during exercise, but increased to resting levels immediately post-exercise, and was further increased at 3 h post-exercise (p < 0.05), but only during the CON trial. Exercise resulted in a marked suppression of whole-body protein synthesis (50% of rest; p < 0.05), which was restored post-exercise; however, the addition of glutamine did not affect whole-body protein synthesis post-exercise. The rate of MPS was not different between trials. The addition of glutamine to a CHO + EAA beverage had no effect on post-exercise muscle glycogen resynthesis or muscle protein synthesis, but may suppress a rise in whole-body proteolysis during the later stages of recovery. PMID:17111006

  16. Free cyclitol, soluble carbohydrate and protein contents in Vigna unguiculata and Phaseolus vulgaris bean sprouts.

    PubMed

    Ribeiro, Elane da Silva; Centeno, Danilo da Cruz; Figueiredo-Ribeiro, Rita de Cássia; Fernandes, Kátia Valevski Sales; Xavier-Filho, José; Oliveira, Antônia Elenir Amancio

    2011-04-27

    Seeds sprouts have been used as a good source of basic nutrients and nutraceutical compounds. The high nutritional value of seeds derives from the deposition of compounds during development. However some of these molecules are used in metabolic processes like germination, which leads to a considerable variation in their concentrations once these events are completed. In this work, we investigate the levels of inositols (myo-inositol, D-pinitol and ononitol), soluble carbohydrates and proteins in cotyledons of Phaseolus vulgaris and Vigna unguiculata sprouts. Sprouting increased myo-inositol and glucose content and reduction of raffinose and ononitol was observed. The protein levels increased in P. vulgaris and decreased in V. unguiculata sprouting. The level of sucrose was maintained in both sprouts. D-Pinitol was detected only in quiescent seeds. Our results suggested that bean sprout is an important source of proteins, sucrose, glucose and myo-inositol. Additionally, bean sprouts have low levels of raffinose, an antinutritional compound.

  17. Dietary carbohydrate restriction induces a unique metabolic state positively affecting atherogenic dyslipidemia, fatty acid partitioning, and metabolic syndrome.

    PubMed

    Volek, Jeff S; Fernandez, Maria Luz; Feinman, Richard D; Phinney, Stephen D

    2008-09-01

    Abnormal fatty acid metabolism and dyslipidemia play an intimate role in the pathogenesis of metabolic syndrome and cardiovascular diseases. The availability of glucose and insulin predominate as upstream regulatory elements that operate through a collection of transcription factors to partition lipids toward anabolic pathways. The unraveling of the details of these cellular events has proceeded rapidly, but their physiologic relevance to lifestyle modification has been largely ignored. Here we highlight the role of dietary input, specifically carbohydrate intake, in the mechanism of metabolic regulation germane to metabolic syndrome. The key principle is that carbohydrate, directly or indirectly through the effect of insulin, controls the disposition of excess dietary nutrients. Dietary carbohydrate modulates lipolysis, lipoprotein assembly and processing and affects the relation between dietary intake of saturated fat intake and circulating levels. Several of these processes are the subject of intense investigation at the cellular level. We see the need to integrate these cellular mechanisms with results from low-carbohydrate diet trials that have shown reduced cardiovascular risk through improvement in hepatic, intravascular, and peripheral processing of lipoproteins, alterations in fatty acid composition, and reductions in other cardiovascular risk factors, notably inflammation. From the current state of the literature, however, low-carbohydrate diets are grounded in basic metabolic principles and the data suggest that some form of carbohydrate restriction is a candidate to be the preferred dietary strategy for cardiovascular health beyond weight regulation.

  18. Protein-carbohydrate supplements improve muscle protein balance in muscular dystrophy patients after endurance exercise: a placebo-controlled crossover study.

    PubMed

    Andersen, Grete; Ørngreen, Mette C; Preisler, Nicolai; Jeppesen, Tina D; Krag, Thomas O; Hauerslev, Simon; van Hall, Gerrit; Vissing, John

    2015-01-15

    In healthy individuals, postexercise protein supplementation increases muscle protein anabolism. In patients with muscular dystrophies, aerobic exercise improves muscle function, but the effect of exercise on muscle protein balance is unknown. Therefore, we investigated 1) muscle protein balance before, during, and after exercise and 2) the effect of postexercise protein-carbohydrate supplementation on muscle protein balance in patients with muscular dystrophies. In 17 patients [7 women and 10 men, aged 33 ± 11 yr (18-52), body mass index: 22 ± 3 kg/m(2) (16-26)] and 8 healthy matched controls [3 women and 5 men, age 33 ± 13 years (19-54), body mass index: 23 ± 3 kg/m(2) (19-27)], muscle protein synthesis, breakdown, and fractional synthesis rates (FSR) were measured across the leg using tracer dilution methodology on two occasions, with and without oral postexercise protein-carbohydrate supplementation. In patients, muscle protein breakdown increased in the recovery period (11 ± 1 μmol phenylalanine/min) vs. rest (8 ± 1 μmol phenylalanine/min, P = 0.02), enhancing net muscle protein loss. In contrast, postexercise protein-carbohydrate supplementation reduced protein breakdown, abolished net muscle protein loss, and increased the muscle FSR in patients (0.04 to 0.06%/h; P = 0.03). In conclusion, postexercise protein-carbohydrate supplementation reduces skeletal mixed-muscle protein breakdown, enhances FSR, resulting in a reduced net muscle loss in patients with muscular dystrophies. The findings suggest that postexercise protein-carbohydrate supplementation could be an important add-on to exercise training therapy in muscular dystrophies, and long-term studies of postexercise protein-carbohydrate supplementation are warranted in these conditions.

  19. The antimicrobial efficacy and structure activity relationship of novel carbohydrate fatty acid derivatives against Listeria spp. and food spoilage microorganisms.

    PubMed

    Nobmann, Patricia; Smith, Aoife; Dunne, Julie; Henehan, Gary; Bourke, Paula

    2009-01-15

    Novel mono-substituted carbohydrate fatty acid (CFA) esters and ethers were investigated for their antibacterial activity against a range of pathogenic and spoilage bacteria focussing on Listeria monocytogenes. Carbohydrate derivatives with structural differences enable comparative studies on the structure/activity relationship for antimicrobial efficacy and mechanism of action. The antimicrobial efficacy of the synthesized compounds was compared with commercially available compounds such as monolaurin and monocaprylin, as well as the pure free fatty acids, lauric acid and caprylic acid, which have proven antimicrobial activity. Compound efficacy was compared using an absorbance based broth microdilution assay to determine the minimum inhibitory concentration (MIC), increase in lag phase and decrease in maximum growth rate. Among the carbohydrate derivatives synthesized, lauric ether of methyl alpha-d-glucopyranoside and lauric ester of methyl alpha-d-mannopyranoside showed the highest growth-inhibitory effect with MIC values of 0.04 mM, comparable to monolaurin. CFA derivatives were generally more active against Gram positive bacteria than Gram negative bacteria. The analysis of both ester and ether fatty acid derivatives of the same carbohydrate, in tandem with alpha and beta configuration of the carbohydrate moiety suggest that the carbohydrate moiety is involved in the antimicrobial activity of the fatty acid derivatives and that the nature of the bond also has a significant effect on efficacy, which requires further investigation. This class of CFA derivatives has great potential for developing antibacterial agents relevant to the food industry, particularly for control of Listeria or other Gram-positive pathogens.

  20. Impact of glucose polymer chain length on heat and physical stability of milk protein-carbohydrate nutritional beverages.

    PubMed

    Chen, Biye; O'Mahony, James A

    2016-11-15

    This study investigated the impact of glucose polymer chain length on heat and physical stability of milk protein isolate (MPI)-carbohydrate nutritional beverages containing 8.5% w/w total protein and 5% w/w carbohydrate. The maltodextrin and corn syrup solids glucose polymers used had dextrose equivalent (DE) values of 17 or 38, respectively. Increasing DE value of the glucose polymers resulted in a greater increase in brown colour development, ionic calcium, protein particle size, apparent viscosity and pseudoplastic rheological behaviour, and greater reduction in pH, hydration and heat stability on sterilisation at 120°C. Incorporation of glucose polymers with MPI retarded sedimentation of protein during accelerated physical stability testing, with maltodextrin DE17 causing a greater reduction in sedimentation velocity and compressibility of sediment formed than corn syrup solids DE38. The results demonstrate that chain length of the glucose polymer used strongly impacts heat and physical stability of MPI-carbohydrate nutritional beverages.

  1. How Phosphotransferase System-Related Protein Phosphorylation Regulates Carbohydrate Metabolism in Bacteria†

    PubMed Central

    Deutscher, Josef; Francke, Christof; Postma, Pieter W.

    2006-01-01

    The phosphoenolpyruvate(PEP):carbohydrate phosphotransferase system (PTS) is found only in bacteria, where it catalyzes the transport and phosphorylation of numerous monosaccharides, disaccharides, amino sugars, polyols, and other sugar derivatives. To carry out its catalytic function in sugar transport and phosphorylation, the PTS uses PEP as an energy source and phosphoryl donor. The phosphoryl group of PEP is usually transferred via four distinct proteins (domains) to the transported sugar bound to the respective membrane component(s) (EIIC and EIID) of the PTS. The organization of the PTS as a four-step phosphoryl transfer system, in which all P derivatives exhibit similar energy (phosphorylation occurs at histidyl or cysteyl residues), is surprising, as a single protein (or domain) coupling energy transfer and sugar phosphorylation would be sufficient for PTS function. A possible explanation for the complexity of the PTS was provided by the discovery that the PTS also carries out numerous regulatory functions. Depending on their phosphorylation state, the four proteins (domains) forming the PTS phosphorylation cascade (EI, HPr, EIIA, and EIIB) can phosphorylate or interact with numerous non-PTS proteins and thereby regulate their activity. In addition, in certain bacteria, one of the PTS components (HPr) is phosphorylated by ATP at a seryl residue, which increases the complexity of PTS-mediated regulation. In this review, we try to summarize the known protein phosphorylation-related regulatory functions of the PTS. As we shall see, the PTS regulation network not only controls carbohydrate uptake and metabolism but also interferes with the utilization of nitrogen and phosphorus and the virulence of certain pathogens. PMID:17158705

  2. Production of hydrogen, ethanol and volatile fatty acids from the seaweed carbohydrate mannitol.

    PubMed

    Xia, Ao; Jacob, Amita; Herrmann, Christiane; Tabassum, Muhammad Rizwan; Murphy, Jerry D

    2015-10-01

    Fermentative hydrogen from seaweed is a potential biofuel of the future. Mannitol, which is a typical carbohydrate component of seaweed, was used as a substrate for hydrogen fermentation. The theoretical specific hydrogen yield (SHY) of mannitol was calculated as 5 mol H2/mol mannitol (615.4 mL H2/g mannitol) for acetic acid pathway, 3 mol H2/mol mannitol (369.2 mL H2/g mannitol) for butyric acid pathway and 1 mol H2/mol mannitol (123.1 mL H2/g mannitol) for lactic acid and ethanol pathways. An optimal SHY of 1.82 mol H2/mol mannitol (224.2 mL H2/g mannitol) was obtained by heat pre-treated anaerobic digestion sludge under an initial pH of 8.0, NH4Cl concentration of 25 mM, NaCl concentration of 50mM and mannitol concentration of 10 g/L. The overall energy conversion efficiency achieved was 96.1%. The energy was contained in the end products, hydrogen (17.2%), butyric acid (38.3%) and ethanol (34.2%).

  3. Computer simulation of protein—carbohydrate complexes: application to arabinose-binding protein and pea lectin

    NASA Astrophysics Data System (ADS)

    Rao, V. S. R.; Biswas, Margaret; Mukhopadhyay, Chaitali; Balaji, P. V.

    1989-03-01

    The CCEM method (Contact Criteria and Energy Minimisation) has been developed and applied to study protein-carbohydrate interactions. The method uses available X-ray data even on the native protein at low resolution (above 2.4 Å) to generate realistic models of a variety of proteins with various ligands. The two examples discussed in this paper are arabinose-binding protein (ABP) and pea lectin. The X-ray crystal structure data reported on ABP-β- L-arabinose complex at 2.8, 2.4 and 1.7 Å resolution differ drastically in predicting the nature of the interactions between the protein and ligand. It is shown that, using the data at 2.4 Å resolution, the CCEM method generates complexes which are as good as the higher (1.7 Å) resolution data. The CCEM method predicts some of the important hydrogen bonds between the ligand and the protein which are missing in the interpretation of the X-ray data at 2.4 Å resolution. The theoretically predicted hydrogen bonds are in good agreement with those reported at 1.7 Å resolution. Pea lectin has been solved only in the native form at 3 Å resolution. Application of the CCEM method also enables us to generate complexes of pea lectin with methyl-α- D-glucopyranoside and methyl-2,3-dimethyl-α- D-glucopyranoside which explain well the available experimental data in solution.

  4. Effects of CO₂ on Acer negundo pollen fertility, protein content, allergenic properties, and carbohydrates.

    PubMed

    Silva, M; Ribeiro, H; Abreu, I; Cruz, A; Esteves da Silva, J C G

    2015-05-01

    Atmospheric gaseous pollutants can induce qualitative and quantitative changes in airborne pollen characteristics. In this work, it was investigated the effects of carbon dioxide (CO2) on Acer negundo pollen fertility, protein content, allergenic properties, and carbohydrates. Pollen was collected directly from the anthers and in vitro exposed to three CO2 levels (500, 1000, and 3000 ppm) for 6 and 24 h in an environmental chamber. Pollen fertility was determined using viability and germination assays, total soluble protein was determined with Coomassie Protein Assay Reagent, and the antigenic and allergenic properties were investigated by sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE) and immunological techniques using patients' sera. Also, pollen fructose, sucrose, and glucose values were determined. Carbon dioxide exposure affected negatively pollen fertility, total soluble protein content, and fructose content. The patient sera revealed increased IgE reactivity to proteins of A. negundo pollen exposed to increasing levels of the pollutant. No changes were detected in the SDS-PAGE protein profiles and in sucrose and glucose levels. Our results indicate that increase in atmospheric CO2 concentrations can have a negative influence of some features of A. negundo airborne pollen that can influence the reproductive processes as well as respiratory pollen allergies in the future.

  5. Species differences in the carbohydrate binding preferences of surfactant protein D.

    PubMed

    Crouch, Erika C; Smith, Kelly; McDonald, Barbara; Briner, David; Linders, Bruce; McDonald, Joseph; Holmskov, Uffe; Head, James; Hartshorn, Kevan

    2006-07-01

    Interactions of surfactant protein D (SP-D) with micro-organisms and organic antigens involve binding to the trimeric neck plus carbohydrate recognition domain (neck+CRD). In these studies, we compared the ligand binding of homologous human, rat, and mouse trimeric neck+CRD fusion proteins, each with identical N-terminal tags remote from the ligand-binding surface. Although rat and mouse showed similar affinities for saccharide competitors, both differed markedly from the human protein. The human neck+CRD preferentially recognized N-acetyl-mannosamine, whereas the rat and mouse proteins showed greater affinity for myoinositol, maltose, and glucose. Although human neck+CRDs bound to maltosyl-agarose and fungal mannan, only rat and mouse neck+CRDs showed significant binding to maltosyl-Toyopearl beads, solid-phase maltosyl-albumin neo-glycoprotein, or the Phil82 strain of influenza A virus. Likewise, human SP-D dodecamers and trimeric subunits of full-length rat, but not full-length human SP-D trimers, bound to maltosyl-Toyopearl. Site-directed mutagenesis of the human neck+CRD demonstrated an important role of Asp324-Asp325 in the recognition of N-acetyl-mannosamine, and substitution of the corresponding murine sequence (Asn324-Asn325) conferred a capacity to interact with immobilized maltose. Thus, ligand recognition by human SP-D involves a complex interplay between saccharide presentation, the valency of trimeric subunits, and species-specific residues that flank the primary carbohydrate binding site.

  6. Energy requirements, protein-energy metabolism and balance, and carbohydrates in preterm infants.

    PubMed

    Hay, William W; Brown, Laura D; Denne, Scott C

    2014-01-01

    Energy is necessary for all vital functions of the body at molecular, cellular, organ, and systemic levels. Preterm infants have minimum energy requirements for basal metabolism and growth, but also have requirements for unique physiology and metabolism that influence energy expenditure. These include body size, postnatal age, physical activity, dietary intake, environmental temperatures, energy losses in the stool and urine, and clinical conditions and diseases, as well as changes in body composition. Both energy and protein are necessary to produce normal rates of growth. Carbohydrates (primarily glucose) are principle sources of energy for the brain and heart until lipid oxidation develops over several days to weeks after birth. A higher protein/energy ratio is necessary in most preterm infants to approximate normal intrauterine growth rates. Lean tissue is predominantly produced during early gestation, which continues through to term. During later gestation, fat accretion in adipose tissue adds increasingly large caloric requirements to the lean tissue growth. Once protein intake is sufficient to promote net lean body accretion, additional energy primarily produces more body fat, which increases almost linearly at energy intakes >80-90 kcal/kg/day in normal, healthy preterm infants. Rapid gains in adiposity have the potential to produce later life obesity, an increasingly recognized risk of excessive energy intake. In addition to fundamental requirements for glucose, protein, and fat, a variety of non-glucose carbohydrates found in human milk may have important roles in promoting growth and development, as well as production of a gut microbiome that could protect against necrotizing enterocolitis.

  7. Effects of step-wise increases in dietary carbohydrate on circulating saturated Fatty acids and palmitoleic Acid in adults with metabolic syndrome.

    PubMed

    Volk, Brittanie M; Kunces, Laura J; Freidenreich, Daniel J; Kupchak, Brian R; Saenz, Catherine; Artistizabal, Juan C; Fernandez, Maria Luz; Bruno, Richard S; Maresh, Carl M; Kraemer, William J; Phinney, Stephen D; Volek, Jeff S

    2014-01-01

    Recent meta-analyses have found no association between heart disease and dietary saturated fat; however, higher proportions of plasma saturated fatty acids (SFA) predict greater risk for developing type-2 diabetes and heart disease. These observations suggest a disconnect between dietary saturated fat and plasma SFA, but few controlled feeding studies have specifically examined how varying saturated fat intake across a broad range affects circulating SFA levels. Sixteen adults with metabolic syndrome (age 44.9±9.9 yr, BMI 37.9±6.3 kg/m2) were fed six 3-wk diets that progressively increased carbohydrate (from 47 to 346 g/day) with concomitant decreases in total and saturated fat. Despite a distinct increase in saturated fat intake from baseline to the low-carbohydrate diet (46 to 84 g/day), and then a gradual decrease in saturated fat to 32 g/day at the highest carbohydrate phase, there were no significant changes in the proportion of total SFA in any plasma lipid fractions. Whereas plasma saturated fat remained relatively stable, the proportion of palmitoleic acid in plasma triglyceride and cholesteryl ester was significantly and uniformly reduced as carbohydrate intake decreased, and then gradually increased as dietary carbohydrate was re-introduced. The results show that dietary and plasma saturated fat are not related, and that increasing dietary carbohydrate across a range of intakes promotes incremental increases in plasma palmitoleic acid, a biomarker consistently associated with adverse health outcomes.

  8. Effects of Step-Wise Increases in Dietary Carbohydrate on Circulating Saturated Fatty Acids and Palmitoleic Acid in Adults with Metabolic Syndrome

    PubMed Central

    Volk, Brittanie M.; Kunces, Laura J.; Freidenreich, Daniel J.; Kupchak, Brian R.; Saenz, Catherine; Artistizabal, Juan C.; Fernandez, Maria Luz; Bruno, Richard S.; Maresh, Carl M.; Kraemer, William J.; Phinney, Stephen D.; Volek, Jeff S.

    2014-01-01

    Recent meta-analyses have found no association between heart disease and dietary saturated fat; however, higher proportions of plasma saturated fatty acids (SFA) predict greater risk for developing type-2 diabetes and heart disease. These observations suggest a disconnect between dietary saturated fat and plasma SFA, but few controlled feeding studies have specifically examined how varying saturated fat intake across a broad range affects circulating SFA levels. Sixteen adults with metabolic syndrome (age 44.9±9.9 yr, BMI 37.9±6.3 kg/m2) were fed six 3-wk diets that progressively increased carbohydrate (from 47 to 346 g/day) with concomitant decreases in total and saturated fat. Despite a distinct increase in saturated fat intake from baseline to the low-carbohydrate diet (46 to 84 g/day), and then a gradual decrease in saturated fat to 32 g/day at the highest carbohydrate phase, there were no significant changes in the proportion of total SFA in any plasma lipid fractions. Whereas plasma saturated fat remained relatively stable, the proportion of palmitoleic acid in plasma triglyceride and cholesteryl ester was significantly and uniformly reduced as carbohydrate intake decreased, and then gradually increased as dietary carbohydrate was re-introduced. The results show that dietary and plasma saturated fat are not related, and that increasing dietary carbohydrate across a range of intakes promotes incremental increases in plasma palmitoleic acid, a biomarker consistently associated with adverse health outcomes. PMID:25415333

  9. Effects of dietary amino acids, carbohydrates, and choline on neurotransmitter synthesis

    NASA Technical Reports Server (NTRS)

    Wurtman, Richard J.

    1988-01-01

    The ability of a meal to increase or decrease brain neurotransmitter synthesis has been studied. It is concluded that brain serotonin synthesis is directly controlled by the proportions of carbohydrate to protein in meals and snacks that increase or decrease brain tryptophan levels, thereby changing the substrate saturation of tryptophan hydroxylase and the rate of serotonin synthesis. The ability of serotoninergic neurons to have their output coupled to dietary macronutrients enables them to function as sensors of peripheral metabolism, and to subserve an important role in the control of appetite. The robust and selective responses of catecholaminergic and cholinergic neurons to supplemental tyrosine and choline suggest that these compounds may become useful as a new type of drug for treating deseases or conditions in which adequate quantities of the transmitter would otherwise be unavailable.

  10. Leucine or carbohydrate supplementation reduces AMPK and eEF2 phosphorylation and extends postprandial muscle protein synthesis in rats.

    PubMed

    Wilson, Gabriel J; Layman, Donald K; Moulton, Christopher J; Norton, Layne E; Anthony, Tracy G; Proud, Christopher G; Rupassara, S Indu; Garlick, Peter J

    2011-12-01

    Muscle protein synthesis (MPS) increases after consumption of a protein-containing meal but returns to baseline values within 3 h despite continued elevations of plasma amino acids and mammalian target of rapamycin (mTORC1) signaling. This study evaluated the potential for supplemental leucine (Leu), carbohydrates (CHO), or both to prolong elevated MPS after a meal. Male Sprague-Dawley rats (∼270 g) trained to consume three meals daily were food deprived for 12 h, and then blood and gastrocnemius muscle were collected 0, 90, or 180 min after a standard 4-g test meal (20% whey protein). At 135 min postmeal, rats were orally administered 2.63 g of CHO, 270 mg of Leu, both, or water (sham control). Following test meal consumption, MPS peaked at 90 min and then returned to basal (time 0) rates at 180 min, although ribosomal protein S6 kinase and eIF4E-binding protein-1 phosphorylation remained elevated. In contrast, rats administered Leu and/or CHO supplements at 135 min postmeal maintained peak MPS through 180 min. MPS was inversely associated with the phosphorylation states of translation elongation factor 2, the "cellular energy sensor" adenosine monophosphate-activated protein kinase-α (AMPKα) and its substrate acetyl-CoA carboxylase, and increases in the ratio of AMP/ATP. We conclude that the incongruity between MPS and mTORC1 at 180 min reflects a block in translation elongation due to reduced cellular energy. Administering Leu or CHO supplements ∼2 h after a meal maintains cellular energy status and extends the postprandial duration of MPS.

  11. Effects of aspartame and carbohydrate administration on human and rat plasma large neutral amino acid levels and rat brain amino acid and monoamine levels.

    PubMed

    Romano, M; Casacci, F; De Marchi, F; Pacei, T; Esteve, A; Lomuscio, G; Mennini, T; Salmona, M

    1989-01-01

    Thirty fasted human volunteers were given 0.83 and 8.3 mg aspartame/kg body weight alone, as part of a basal low carbohydrate meal (648 kcal, 10% carbohydrate) or as part of a high energy carbohydrate-rich meal (1290 kcal, 34% carbohydrate). Amino acid concentrations in plasma were determined before and 30, 60 and 180 min after the consumption of aspartame. Under these conditions, which mimic realistic aspartame consumption, aspartame had no significant effect on plasma concentration of any amino acid. In addition, the effect of aspartame alone or with carbohydrates on plasma and brain amino acid levels was studied in rats after acute or subacute (14 d) oral treatment. In subacute dosing experiments aspartame was included in the diet. Brain monoamine concentrations were also measured in the same animals. Plasma concentrations of large neutral amino acids were modified under acute conditions. In contrast, after subacute treatment no significant differences in plasma or brain amino acid concentrations or in brain monoamine concentrations were observed.

  12. Synthesis and emulsifying properties of carbohydrate fatty acid esters produced from Agave tequilana fructans by enzymatic acylation.

    PubMed

    Casas-Godoy, Leticia; Arrizon, Javier; Arrieta-Baez, Daniel; Plou, Francisco J; Sandoval, Georgina

    2016-08-01

    Carbohydrate fatty acid esters are non-ionic surfactants with a broad spectrum of applications. These molecules are generally synthesized using short carbohydrates or linear fructans; however in this research carbohydrate fatty acid esters were produced for the first time with branched fructans from Agave tequilana. Using immobilized lipases we successfully acylated A. tequilana fructans with vinyl laurate, obtaining products with different degrees of polymerization (DP). Lipozyme 435 was the most efficient lipase to catalyze the transesterification reaction. HPLC and ESI-MS analysis proved the presence of a mixture of acylated products as a result of the chemical complexity of fructans in the A. tequilana. The ESI-MS spectra showed a molecular mass shift between 183 and 366g/mol for fructooligosaccharides with a DP lower than 6, which indicated the presence of Agave fructans that had been mono- and diacylated with lauric acid. The carbohydrate fatty acid esters (CFAE) obtained showed good emulsifying properties in W/O emulsions. PMID:26988522

  13. The effects of a carbohydrate-protein gel supplement on alpine slalom ski performance.

    PubMed

    Seifert, John G; Kipp, Ronald W; Bacharach, David W

    2012-01-01

    Alpine slalom ski racing is a high intensity, complex sport in which racers execute turns every second. Acute fatigue can make the difference in not finishing a run (DNF) or finishing out of contention. The quantity and quality of training often dictates racing success. It is not known if nutritional supplementation can improve performance in this high intensity, short duration activity. The objective of this study was to determine if ingesting a carbohydrate-protein energy gel (GEL) improves finishing success and number of gates completed during 2 hr slalom sessions on two consecutive days of training. Twenty-four racers were matched; one group ingested the GEL, the second group received a liquid placebo (PLA). Total carbohy-drate, protein, and water ingested by the GEL group were 60g, 15g, and 450 mL, while the PLA group ingested 450 mL of PLA. The GEL group had significantly fewer DNF's (7/48 vs. 18/48; p = 0.02) on both days, completed a greater number of training gates on Day 2 (260.3 ± 20.1 vs. 246.3 ± 17.5 gates; p = 0.03), and had a lower RPE (3.9 ± 1.2 vs. 5.3 ± 1.2 on Day 2 (p = 0.004) vs. PLA. The statistical analysis of combined finishing times was not possible due to the high number of DNF's in the PLA group. High intensity slalom performance can be im-proved by the ingestion of an energy gel. The GEL allowed the athletes to improve training quantity and quality and their per-ception of effort was less than skiers who ingested a placebo. Key pointsNutritional supplementation with a carbohydrate/protein sports gel during high intensity ski training improved training volume as measured by the number gates completed.Supplementation also reduced the number of DNF's during training.Racers' perception of effort was significantly lower with the supplement ingestion compared to a non-caloric placebo.This applied study was conducted under real life field conditions and training environments.

  14. Updating the Cornell Net Carbohydrate and Protein System feed library and analyzing model sensitivity to feed inputs.

    PubMed

    Higgs, R J; Chase, L E; Ross, D A; Van Amburgh, M E

    2015-09-01

    The Cornell Net Carbohydrate and Protein System (CNCPS) is a nutritional model that evaluates the environmental and nutritional resources available in an animal production system and enables the formulation of diets that closely match the predicted animal requirements. The model includes a library of approximately 800 different ingredients that provide the platform for describing the chemical composition of the diet to be formulated. Each feed in the feed library was evaluated against data from 2 commercial laboratories and updated when required to enable more precise predictions of dietary energy and protein supply. A multistep approach was developed to predict uncertain values using linear regression, matrix regression, and optimization. The approach provided an efficient and repeatable way of evaluating and refining the composition of a large number of different feeds against commercially generated data similar to that used by CNCPS users on a daily basis. The protein A fraction in the CNCPS, formerly classified as nonprotein nitrogen, was reclassified to ammonia for ease and availability of analysis and to provide a better prediction of the contribution of metabolizable protein from free AA and small peptides. Amino acid profiles were updated using contemporary data sets and now represent the profile of AA in the whole feed rather than the insoluble residue. Model sensitivity to variation in feed library inputs was investigated using Monte Carlo simulation. Results showed the prediction of metabolizable energy was most sensitive to variation in feed chemistry and fractionation, whereas predictions of metabolizable protein were most sensitive to variation in digestion rates. Regular laboratory analysis of samples taken on-farm remains the recommended approach to characterizing the chemical components of feeds in a ration. However, updates to the CNCPS feed library provide a database of ingredients that are consistent with current feed chemistry information and

  15. Methylmalonic acid blood test

    MedlinePlus

    ... acid is a substance produced when proteins, called amino acids, in the body break down. The health care ... Cederbaum S, Berry GT. Inborn errors of carbohydrate, ammonia, amino acid, and organic acid metabolism. In: Gleason CA, Devaskar ...

  16. Effects of inadequate maternal dietary protein:carbohydrate ratios during pregnancy on offspring immunity in pigs

    PubMed Central

    2012-01-01

    Background Inadequate nutrition in utero may retard foetal growth and alter physiological development of offspring. This study investigated the effects of low and high protein diets fed to primiparous German Landrace sows throughout pregnancy on the immune function of their offspring at different ages. Sows were fed diets with adequate (AP, 12.1%; n = 13), low (LP, 6.5%; n = 15), or high (HP, 30%; n = 14) protein content, made isoenergetic by varying carbohydrate levels. Cortisol, total protein and immunoglobulin (IgG, IgM, IgA) concentrations were measured in the blood of sows over the course of pregnancy. Cortisol, total protein, immunoglobulins, lymphocyte proliferation, immune cell counts, and cytokines were assessed in the blood of offspring at baseline and under challenging conditions (weaning; lipopolysaccharide (LPS) administration). Results In sows, the LP diet increased cortisol (P < 0.05) and decreased protein levels (P < 0.01) at the end of pregnancy. Immunoglobulin concentrations were decreased in LP (IgA) and HP piglets (IgG, IgM and IgA) on the first day of life (P < 0.05), whereas the number of lymphocytes and mitogen-induced lymphocyte proliferation of the piglets were unaffected by the maternal diet. Mortality during the suckling period was higher in LP piglets compared with AP and HP offspring (P < 0.01). Furthermore, LP piglets showed an elevated cortisol response to weaning, and in HP piglets, the CD4+ cell percentage and the CD4+/CD8+ ratio increased after weaning (P < 0.05). The lipopolysaccharide-induced rise of IL-6 was higher in LP (P = 0.09) and HP (P < 0.01) compared with AP piglets, and LP piglets displayed higher IL-10 levels than AP piglets (P < 0.05). Conclusions Our results indicate that both low and high protein:carbohydrate ratios in the diet of pregnant sows can induce short-term as well as long-lasting effects on immune competence in piglets that may have serious consequences for host

  17. Elucidating glycosaminoglycan–protein–protein interactions using carbohydrate microarray and computational approaches

    PubMed Central

    Rogers, Claude J.; Clark, Peter M.; Tully, Sarah E.; Abrol, Ravinder; Garcia, K. Christopher; Goddard, William A.; Hsieh-Wilson, Linda C.

    2011-01-01

    Glycosaminoglycan polysaccharides play critical roles in many cellular processes, ranging from viral invasion and angiogenesis to spinal cord injury. Their diverse biological activities are derived from an ability to regulate a remarkable number of proteins. However, few methods exist for the rapid identification of glycosaminoglycan–protein interactions and for studying the potential of glycosaminoglycans to assemble multimeric protein complexes. Here, we report a multidisciplinary approach that combines new carbohydrate microarray and computational modeling methodologies to elucidate glycosaminoglycan–protein interactions. The approach was validated through the study of known protein partners for heparan and chondroitin sulfate, including fibroblast growth factor 2 (FGF2) and its receptor FGFR1, the malarial protein VAR2CSA, and tumor necrosis factor-α (TNF-α). We also applied the approach to identify previously undescribed interactions between a specific sulfated epitope on chondroitin sulfate, CS-E, and the neurotrophins, a critical family of growth factors involved in the development, maintenance, and survival of the vertebrate nervous system. Our studies show for the first time that CS is capable of assembling multimeric signaling complexes and modulating neurotrophin signaling pathways. In addition, we identify a contiguous CS-E-binding site by computational modeling that suggests a potential mechanism to explain how CS may promote neurotrophin-tyrosine receptor kinase (Trk) complex formation and neurotrophin signaling. Together, our combined microarray and computational modeling methodologies provide a general, facile means to identify new glycosaminoglycan–protein–protein interactions, as well as a molecular-level understanding of those complexes. PMID:21628576

  18. Apoptosis induced by a low-carbohydrate and high-protein diet in rat livers

    PubMed Central

    Monteiro, Maria Emília L; Xavier, Analucia R; Oliveira, Felipe L; Filho, Porphirio JS; Azeredo, Vilma B

    2016-01-01

    AIM: To determine whether high-protein, high-fat, and low-carbohydrate diets can cause lesions in rat livers. METHODS: We randomly divided 20 female Wistar rats into a control diet group and an experimental diet group. Animals in the control group received an AIN-93M diet, and animals in the experimental group received an Atkins-based diet (59.46% protein, 31.77% fat, and 8.77% carbohydrate). After 8 wk, the rats were anesthetized and exsanguinated for transaminases analysis, and their livers were removed for flow cytometry, immunohistochemistry, and light microscopy studies. We expressed the data as mean ± standard deviation (SD) assuming unpaired and parametric data; we analyzed differences using the Student’s t-test. Statistical significance was set at P < 0.05. RESULTS: We found that plasma alanine aminotransferase and aspartate aminotransferase levels were significantly higher in the experimental group than in the control group. According to flow cytometry, the percentages of nonviable cells were 11.67% ± 1.12% for early apoptosis, 12.07% ± 1.11% for late apoptosis, and 7.11% ± 0.44% for non-apoptotic death in the experimental diet group and 3.73% ± 0.50% for early apoptosis, 5.67% ± 0.72% for late apoptosis, and 3.82% ± 0.28% for non-apoptotic death in the control diet group. The mean percentage of early apoptosis was higher in the experimental diet group than in the control diet group. Immunohistochemistry for autophagy was negative in both groups. Sinusoidal dilation around the central vein and small hepatocytes was only observed in the experimental diet group, and fibrosis was not identified by hematoxylin-eosin or Trichrome Masson staining in either group. CONCLUSION: Eight weeks of an experimental diet resulted in cellular and histopathological lesions in rat livers. Apoptosis was our principal finding; elevated plasma transaminases demonstrate hepatic lesions. PMID:27298559

  19. An olive pollen protein with allergenic activity, Ole e 10, defines a novel family of carbohydrate-binding modules and is potentially implicated in pollen germination

    PubMed Central

    2005-01-01

    CBMs (carbohydrate-binding modules) are the most common non-catalytic modules associated with enzymes active in plant cell-wall hydrolysis. They have been frequently identified by amino acid sequence alignments, but only a few have been experimentally established to have a carbohydrate-binding activity. A small olive pollen protein, Ole e 10 (10 kDa), has been described as a major inducer of type I allergy in humans. In the present study, the ability of Ole e 10 to bind several polysaccharides has been analysed by affinity gel electrophoresis, which demonstrated that the protein bound 1,3-β-glucans preferentially. Analytical ultracentrifugation studies confirmed binding to laminarin, at a protein/ligand ratio of 1:1. The interaction of Ole e 10 with laminarin induced a conformational change in the protein, as detected by CD and fluorescence analyses, and an increase of 3.6 °C in the thermal denaturation temperature of Ole e 10 in the presence of the glycan. These results, and the absence of alignment of the sequence of Ole e 10 with that of any classified CBM, indicate that this pollen protein defines a novel family of CBMs, which we propose to name CBM43. Immunolocalization of Ole e 10 in mature and germinating pollen by transmission electron microscopy and confocal laser scanning microscopy demonstrated the co-localization of Ole e 10 and callose (1,3-β-glucan) in the growing pollen tube, suggesting a role for this protein in the metabolism of carbohydrates and in pollen tube wall re-formation during germination. PMID:15882149

  20. Alginic acid synthesis in Pseudomonas aeruginosa mutants defective in carbohydrate metabolism.

    PubMed Central

    Banerjee, P C; Vanags, R I; Chakrabarty, A M; Maitra, P K

    1983-01-01

    Mutant cells of mucoid Pseudomonas aeruginosa isolated from cystic fibrosis patients were examined for their ability to synthesize alginic acid in resting cell suspensions. Unlike the wild-type strain which synthesizes alginic acid from glycerol, fructose, mannitol, glucose, gluconate, glutamate, or succinate, mutants lacking specific enzymes of carbohydrate metabolism are uniquely impaired. A phosphoglucose isomerase mutant did not synthesize the polysaccharide from mannitol, nor did a glucose 6-phosphate dehydrogenase mutant synthesize the polysaccharide from mannitol or glucose. Mutants lacking the Entner-Doudoroff pathway dehydrase or aldolase failed to produce alginate from mannitol, glucose, or gluconate, as a 3-phosphoglycerate kinase or glyceraldehyde 3-phosphate dehydrogenase mutant failed to produce from glutamate or succinate. These results demonstrate the primary role of the Entner-Doudoroff pathway enzymes in the synthesis of alginate from glucose, mannitol, or gluconate and the role of glyceraldehyde 3-phosphate dehydrogenase reaction for the synthesis from gluconeogenic precursors such as glutamate. The virtual absence of any activity of phosphomannose isomerase in cell extracts of several independent mucoid bacteria and the impairment of alginate synthesis from mannitol in mutants lacking phosphoglucose isomerase or glucose 6-phosphate dehydrogenase rule out free mannose 6-phosphate as an intermediate in alginate biosynthesis. PMID:6408061

  1. Proteins and acids from petroleum.

    PubMed

    Zaki, D; el-Badrawy, S

    1978-01-01

    The wax distillate fraction (boiling range 300 up to 400 degrees C) from the crude oil "El-Alameen" was found to be a good substrate for the biosynthesis of proteins and/or amino acids by bacteria under special culture conditions. The fermentation processes were accompanied by a refining effect to the oil fraction, elevating its refraction index and lowering its melting point, giving dewaxing effect to the oil fraction. PMID:735504

  2. Differential effects of proteins and carbohydrates on postprandial blood pressure-related responses.

    PubMed

    Teunissen-Beekman, Karianna F M; Dopheide, Janneke; Geleijnse, Johanna M; Bakker, Stephan J L; Brink, Elizabeth J; de Leeuw, Peter W; Serroyen, Jan; van Baak, Marleen A

    2014-08-28

    Diet composition may affect blood pressure (BP), but the mechanisms are unclear. The aim of the present study was to compare postprandial BP-related responses to the ingestion of pea protein, milk protein and egg-white protein. In addition, postprandial BP-related responses to the ingestion of maltodextrin were compared with those to the ingestion of sucrose and a protein mix. We hypothesised that lower postprandial total peripheral resistance (TPR) and BP levels would be accompanied by higher plasma concentrations of nitric oxide, insulin, glucagon-like peptide 1 (GLP-1) and glucagon. On separate occasions, six meals were tested in a randomised order in forty-eight overweight or obese adults with untreated elevated BP. Postprandial responses of TPR, BP and plasma concentrations of insulin, glucagon, GLP-1 and nitrite, nitroso compounds (RXNO) and S-nitrosothiols (NO(x)) were measured for 4 h. No differences were observed in TPR responses. Postprandial BP levels were higher after the ingestion of the egg-white-protein meal than after that of meals containing the other two proteins (P≤ 0·01). The ingestion of the pea-protein meal induced the highest NO(x) response (P≤ 0·006). Insulin and glucagon concentrations were lowest after the ingestion of the egg-white-protein meal (P≤ 0·009). Postprandial BP levels were lower after the ingestion of the maltodextrin meal than after that of the protein mix and sucrose meals (P≤ 0·004), while postprandial insulin concentrations were higher after the ingestion of the maltodextrin meal than after that of the sucrose and protein mix meals after 1-2 h (P≤ 0·0001). Postprandial NO(x), GLP-1 and glucagon concentrations were lower after the ingestion of the maltodextrin meal than after that of the protein mix meal (P≤ 0·008). In conclusion, different protein and carbohydrate sources induce different postprandial BP-related responses, which may be important for BP management. Lower postprandial BP levels are not

  3. Quantitative determination of carboxylic acids, amino acids, carbohydrates, ethanol and hydroxymethylfurfural in honey by (1)H NMR.

    PubMed

    del Campo, Gloria; Zuriarrain, Juan; Zuriarrain, Andoni; Berregi, Iñaki

    2016-04-01

    A method using (1)H NMR spectroscopy has been developed to quantify simultaneously thirteen analytes in honeys without previous separation or pre-concentration steps. The method has been successfully applied to determine carboxylic acids (acetic, formic, lactic, malic and succinic acids), amino acids (alanine, phenylalanine, proline and tyrosine), carbohydrates (α- and β-glucose and fructose), ethanol and hydroxymethylfurfural in eucalyptus, heather, lavender, orange blossom, thyme and rosemary honeys. Quantification was performed by using the area of the signal of each analyte in the honey spectra, together with external standards. The regression analysis of the signal area against concentration plots, used for the calibration of each analyte, indicates a good linearity over the concentration ranges found in honeys, with correlation coefficients higher than 0.985 for the thirteen quantified analytes. The recovery studies give values over the 93.7-105.4% range with relative standard deviations lower than 7.4%. Good precision, with relative standard deviations over the range of 0.78-5.21% is obtained. PMID:26593586

  4. Quantitative determination of carboxylic acids, amino acids, carbohydrates, ethanol and hydroxymethylfurfural in honey by (1)H NMR.

    PubMed

    del Campo, Gloria; Zuriarrain, Juan; Zuriarrain, Andoni; Berregi, Iñaki

    2016-04-01

    A method using (1)H NMR spectroscopy has been developed to quantify simultaneously thirteen analytes in honeys without previous separation or pre-concentration steps. The method has been successfully applied to determine carboxylic acids (acetic, formic, lactic, malic and succinic acids), amino acids (alanine, phenylalanine, proline and tyrosine), carbohydrates (α- and β-glucose and fructose), ethanol and hydroxymethylfurfural in eucalyptus, heather, lavender, orange blossom, thyme and rosemary honeys. Quantification was performed by using the area of the signal of each analyte in the honey spectra, together with external standards. The regression analysis of the signal area against concentration plots, used for the calibration of each analyte, indicates a good linearity over the concentration ranges found in honeys, with correlation coefficients higher than 0.985 for the thirteen quantified analytes. The recovery studies give values over the 93.7-105.4% range with relative standard deviations lower than 7.4%. Good precision, with relative standard deviations over the range of 0.78-5.21% is obtained.

  5. Comparison of Postexercise Nutrition Knowledge and Postexercise Carbohydrate and Protein Intake Between Australian Masters and Younger Triathletes.

    PubMed

    Doering, Thomas M; Reaburn, Peter R; Cox, Gregory; Jenkins, David G

    2016-08-01

    Postexercise nutrition is a critical component of an athlete's recovery from training and competition. However, little is known about athletes' postexercise dietary practices or knowledge of dietary recommendations, particularly among masters athletes. The purpose of this study was to compare and contrast the knowledge of postexercise nutritional recommendations, and typical postexercise intakes of carbohydrate and protein, between masters and younger triathletes. 182 triathletes (Male = 101, Female = 81) completed an online survey distributed by Triathlon Australia. Knowledge of postexercise nutrition recommendations for protein and carbohydrate intake were assessed as a group, and contrasted between subgroups of masters (≥50 years) and younger triathletes (≤30 years). Using dietary recall, postexercise intakes of carbohydrate and protein were examined and contrasted between masters and younger triathletes. As a group, 43.1% and 43.9% of all triathletes answered, "I don't know" when asked to identify the recommended postexercise carbohydrate and protein intakes, respectively. Dietary analysis revealed masters triathletes consumed significantly less carbohydrate (0.7 ± 0.4 g.kg-1) postexercise than recommended (1.0 g.kg-1; p = .001), and in comparison with younger triathletes (1.1 ± 0.6 g.kg-1; p = .01). Postexercise protein intakes were similar between masters (19.6 ± 13.5 g) and younger (26.4 ± 15.8 g) triathletes. However, relative to body mass, masters triathletes consumed significantly less protein (0.3 ± 0.2 g.kg-1) than younger triathletes (0.4 ± 0.2 g.kg-1; p = .03), and consumed significantly less energy postexercise (22.7 ± 11.7 kJ.kg-1) than younger triathletes (37.8 ± 19.2 kJ.kg-1; p = .01). The present data suggests triathletes have poor knowledge of recommendations for postexercise carbohydrate and protein intakes. Furthermore, low postexercise intakes of carbohydrate and protein by masters athletes may impair acute recovery.

  6. Effect of varying the concentrations of carbohydrate and milk protein in rehydration solutions ingested after exercise in the heat.

    PubMed

    James, Lewis J; Evans, Gethin H; Madin, Joshua; Scott, Darren; Stepney, Michael; Harris, Russell; Stone, Robert; Clayton, David J

    2013-10-01

    The present study investigated the relationship between the milk protein content of a rehydration solution and fluid balance after exercise-induced dehydration. On three occasions, eight healthy males were dehydrated to an identical degree of body mass loss (BML, approximately 1·8%) by intermittent cycling in the heat, rehydrating with 150% of their BML over 1 h with either a 60 g/l carbohydrate solution (C), a 40 g/l carbohydrate, 20 g/l milk protein solution (CP20) or a 20 g/l carbohydrate, 40 g/l milk protein solution (CP40). Urine samples were collected pre-exercise, post-exercise, post-rehydration and for a further 4 h. Subjects produced less urine after ingesting the CP20 or CP40 drink compared with the C drink (P<0·01), and at the end of the study, more of the CP20 (59 (SD 12)%) and CP40 (64 (SD 6)%) drinks had been retained compared with the C drink (46 (SD 9)%) (P<0·01). At the end of the study, whole-body net fluid balance was more negative for trial C (- 470 (SD 154) ml) compared with both trials CP20 (- 181 (SD 280) ml) and CP40 (2107 (SD 126) ml) (P<0·01). At 2 and 3 h after drink ingestion, urine osmolality was greater for trials CP20 and CP40 compared with trial C (P<0·05). The present study further demonstrates that after exercise-induced dehydration, a carbohydrate--milk protein solution is better retained than a carbohydrate solution. The results also suggest that high concentrations of milk protein are not more beneficial in terms of fluid retention than low concentrations of milk protein following exercise-induced dehydration.

  7. Protein-sparing effect of carbohydrate in diets for juvenile turbot Scophthalmus maximus reared at different salinities

    NASA Astrophysics Data System (ADS)

    Zeng, Lin; Lei, Jilin; Ai, Chunxiang; Hong, Wanshu; Liu, Bin

    2015-01-01

    The aim of the present study was to investigate the protein-sparing effect of carbohydrate in diets for juvenile turbot ( Scophthalmus maximus) reared at five salinities (12, 18, 24, 30, and 36). The fish were fed three isocaloric and isolipidic diets for 60 days. The results show that specific growth rate (SGR) and feed conversion efficiency (FCE) were higher in fish reared at salinities of 18 and 36, but lower at 12. Fish fed with diet C25P40 (25% carbohydrate and 40% protein) had lower SGR and FCE values compared with those fed with the C5P52 (5% carbohydrate and 52% protein) and C15P46 (15% carbohydrate and 46% protein) diets; however, there was no statistical difference between diet C5P52 and C15P46. SGR and FCE values were unaffected by diet composition in fish reared at salinity 36. Hepatic lipogenic enzyme activities were higher in fish reared at 18 and 36, but lower at 12, while glucokinase (GK) activity was higher in fish reared at 12, and lower at 18 and 36. Dietary starch enhanced GK activity while depressing lipogenic enzyme activity. However, lipogenic enzyme activity increased with increasing dietary starch in fish reared at 36. It is recommended that salinity should be maintained >12 in the farming of juvenile turbot. In addition, an increase in gelatinized starch from 5% to 15% could spare 6% dietary protein in fish reared at salinities of 18-30, while higher salinity (36) could improve dietary carbohydrate use and enhance the protein-sparing effect, which is linked with the induction of lipogenic capacities.

  8. Effect of quarantine treatments on the carbohydrate and organic acid content of mangoes (cv. Tommy Atkins)

    NASA Astrophysics Data System (ADS)

    Cruz, J. N.; Soares, C. A.; Fabbri, A. D. T.; Cordenunsi, B. R.; Sabato, S. F.

    2012-08-01

    Brazil is one of the largest mango producers and the third largest mango exporter worldwide. Irradiation treatment and its commercial feasibility have been studied in our country to make it possible to develop new markets and, consequently, to compete with the major exporters of mangoes, Mexico and India. This work was designed to compare irradiation treatment with the hot water dip treatment in mangoes cv. Tommy Atkins for export and to verify that the main attributes for acceptance, color and texture, as well as carbohydrate and organic acid contents, were maintained. In this study, the fruit was divided into groups: control, hot water dip-treated (46 °C for 90 min), and irradiation-treated at doses of 0.4 kGy and 1.0 kGy. The fruit was stored at low temperature (11 °C±2) for 14 days and then at room temperature (23 °C±2) until the end of the study. The results indicated that the fruit given a dose of 1.0 kGy remained in a less advanced stage of ripening (stage 3) throughout the storage period, but experienced a greater loss of texture in the beginning of the experiment. It was noted that only the control group had higher levels of citric acid and succinic acid on the last day of the experiment. There were no significant differences in the total sugar content between any treatment groups. Gamma radiation can be used as a quarantine treatment and does not interfere negatively with the quality attributes of mangoes.

  9. Spatiotemporal variation of dissolved carbohydrates and amino acids in Jiaozhou Bay, China

    NASA Astrophysics Data System (ADS)

    Shi, Di; Yang, Guipeng; Sun, Yan; Wu, Guanwei

    2016-06-01

    Surface seawater samples were collected from Jiaozhou Bay, China, during six cruises (March-May 2010, September-November 2010) to study the distribution of dissolved organic matter including dissolved organic carbon (DOC), total dissolved carbohydrates, namely monosaccharides (MCHO) and polysaccharides (PCHO) and total hydrolysable amino acids. These included dissolved free amino acids (DFAA) and combined amino acids (DCAA). The goal was to investigate possible relationships between these dissolved organic compounds and environmental parameters. During spring, the concentrations of MCHO and PCHO were 9.6 (2.8-22.6) and 11.0 (2.9-42.5) μmol C/L, respectively. In autumn, MCHO and PCHO were 9.1 (2.6-27.0) and 10.8 (2.4-25.6) μmol C/L, respectively. The spring concentrations of DFAA and DCAA were 1.7 (1.1-4.1) and 7.6 (1.1-31.0) μmol C/L, respectively, while in autumn, DFAA and DCAA were 2.3 (1.1-8.0) and 3.3 (0.6-7.2) μmol C/L, respectively. Among these compounds, the concentrations of PCHO were the highest, accounting for nearly a quarter of the DOC, followed by MCHO, DCAA and DFAA. The concentrations of the organic compounds exhibited a decreasing trend from the coastal to the central regions of the bay. A negative correlation between concentrations of DOC and salinity in each cruise suggested that riverine inputs around the bay have an important impact on the distribution of DOC in the surface water. A significant positive correlation was found between DOC and total bacteria count in spring and autumn, suggesting bacteria play an important role in the marine carbon cycle.

  10. Influences of carbohydrate plus amino acid supplementation on differing exercise intensity adaptations in older persons: skeletal muscle and endocrine responses.

    PubMed

    Onambélé-Pearson, Gladys Leopoldine; Breen, Leigh; Stewart, Claire E

    2010-06-01

    Losses in physiological function in healthy ageing occur partly as a consequence of reduced protein intake and partly as a consequence of less than 30-min/day of moderate to vigorous physical activity. The current study aimed to compare the effects of two different intensities of resistance training in healthy older adults, whose habitual dietary intake was supplemented with carbohydrate and amino acid preparations. We hypothesised that although intensive exercise with appropriate carbohydrate and amino acid supplementation would result in the most profound impact on in vivo markers of healthy physiologic and endocrine functions in previously sedentary older individuals, the effectiveness of the less intense exercise prescription with supplementation would also result in beneficial adaptations over and above findings of previous studies on low intensity exercise alone. Twenty-nine older adults (out of 32) completed the study after being randomly assigned to low (SUP_LowR, i.e., approximately 40% 1RM; n = 16) versus high resistance training (SUP_HighR, i.e., approximately 80% 1RM; n = 13) for 12 weeks. A carbohydrate supplement was ingested immediately before and during every exercise session and an amino acid cocktail was ingested post-exercise. Neither intervention significantly impacted upon body composition assessed using: Body mass index, waist/hip ratio and bioelectric impedance. Muscle strength increased similarly in the two groups with the SUP_HighR protocol showing 46 +/- 8%, 10.8 +/- 4.4% and 26.9 +/- 4.9% (P < 0.01) improvements in 1-RM strength, unilateral and bilateral knee extension torque, respectively, compared with 39 +/- 2%, 9.4 +/- 3.7% and 29.5 +/- 8.2% (P < 0.01) increments in the same measures in the SUP_LowR group. Lean muscle thickness however, showed a greater benefit of the SUP_LowR protocol (8.7 +/- 3.9% increase, P < 0.05) compared with the SUP_HighR protocol, which elicited no significant change. In terms of functional abilities, only

  11. Effect of hyperbaric oxygenation on carbohydrate metabolism protein synthesis in the myocardium during sustained hypodynamia

    NASA Technical Reports Server (NTRS)

    Makarov, G. A.

    1980-01-01

    Glycolysis and the intensity of protein synthesis were studied in 140 white male rats in subcellular fractions of the myocardium during 45 day hypodynamia and hyperbaric oxygenation. Hypodynamia increased: (1) the amount of lactic acids; (2) the amount of pyruvic acid; (3) the lactate/pyruvate coefficient; and (4) the activities of aldolase and lactate dehydrogenase. Hyperbaric oxygenation was found to have a favorable metabolic effect on the animals with hypodynamia.

  12. [Influence of bean yellow mosaic virus on metabolism of photosynthetic pigments, proteins and carbohydrates in Glycine soja L].

    PubMed

    Kyrychenko, A M

    2014-01-01

    This paper presents data on BYMV effects on some physiological processes of Glycine soja L. cultivated in the right-bank forest-steppe regions. Pigment content (chlorophyll a, b and carotenoids), soluble proteins and water soluble carbohydrates were estimated and, as has been shown, are subjected to significant changes as compared with control plants, namely: a decrease in the content of chlorophyll a, b and carotenoids was 64%, 53% and 36% compared with the control plants. The significant increase in carbohydrates (56% compared to the control) was observed at the end of the test period.

  13. Influence of thermally processed carbohydrate/amino acid mixtures on the fermentation by Saccharomyces cerevisiae.

    PubMed

    Tauer, Andreas; Elss, Sandra; Frischmann, Matthias; Tellez, Patricia; Pischetsrieder, Monika

    2004-04-01

    The production of alcoholic beverages such as Tequila, Mezcal, whiskey, or beer includes the fermentation of a mash containing Maillard reaction products. Because excessive heating of the mash can lead to complications during the following fermentation step, the impact of Maillard products on the metabolism of Saccharomyces cerevisiae was investigated. For this purpose, fermentation was carried out in a model system in the presence and absence of Maillard reaction products and formation of ethanol served as a marker for the progression of fermentation. We found that increasing amounts of Maillard products reduced the formation of ethanol up to 80%. This effect was dependent on the pH value during the Maillard reaction, reaction time, as well as the carbohydrate and amino acid component used for the generation of Maillard reaction products. Another important factor is the pH value during fermentation: The inhibitory effect of Maillard products was not detectable at a pH of 4 and increased with higher pH-values. These findings might be of relevance for the production of above-mentioned beverages.

  14. Influence of thermally processed carbohydrate/amino acid mixtures on the fermentation by Saccharomyces cerevisiae.

    PubMed

    Tauer, Andreas; Elss, Sandra; Frischmann, Matthias; Tellez, Patricia; Pischetsrieder, Monika

    2004-04-01

    The production of alcoholic beverages such as Tequila, Mezcal, whiskey, or beer includes the fermentation of a mash containing Maillard reaction products. Because excessive heating of the mash can lead to complications during the following fermentation step, the impact of Maillard products on the metabolism of Saccharomyces cerevisiae was investigated. For this purpose, fermentation was carried out in a model system in the presence and absence of Maillard reaction products and formation of ethanol served as a marker for the progression of fermentation. We found that increasing amounts of Maillard products reduced the formation of ethanol up to 80%. This effect was dependent on the pH value during the Maillard reaction, reaction time, as well as the carbohydrate and amino acid component used for the generation of Maillard reaction products. Another important factor is the pH value during fermentation: The inhibitory effect of Maillard products was not detectable at a pH of 4 and increased with higher pH-values. These findings might be of relevance for the production of above-mentioned beverages. PMID:15053549

  15. Glucose-6-phosphate mediates activation of the carbohydrate responsive binding protein (ChREBP)

    SciTech Connect

    Li, Ming V.; Chen, Weiqin; Harmancey, Romain N.; Nuotio-Antar, Alli M.; Imamura, Minako; Saha, Pradip; Taegtmeyer, Heinrich; Chan, Lawrence

    2010-05-07

    Carbohydrate response element binding protein (ChREBP) is a Mondo family transcription factor that activates a number of glycolytic and lipogenic genes in response to glucose stimulation. We have previously reported that high glucose can activate the transcriptional activity of ChREBP independent of the protein phosphatase 2A (PP2A)-mediated increase in nuclear entry and DNA binding. Here, we found that formation of glucose-6-phosphate (G-6-P) is essential for glucose activation of ChREBP. The glucose response of GAL4-ChREBP is attenuated by D-mannoheptulose, a potent hexokinase inhibitor, as well as over-expression of glucose-6-phosphatase (G6Pase); kinetics of activation of GAL4-ChREBP can be modified by exogenously expressed GCK. Further metabolism of G-6-P through the two major glucose metabolic pathways, glycolysis and pentose-phosphate pathway, is not required for activation of ChREBP; over-expression of glucose-6-phosphate dehydrogenase (G6PD) diminishes, whereas RNAi knockdown of the enzyme enhances, the glucose response of GAL4-ChREBP, respectively. Moreover, the glucose analogue 2-deoxyglucose (2-DG), which is phosphorylated by hexokinase, but not further metabolized, effectively upregulates the transcription activity of ChREBP. In addition, over-expression of phosphofructokinase (PFK) 1 and 2, synergistically diminishes the glucose response of GAL4-ChREBP. These multiple lines of evidence support the conclusion that G-6-P mediates the activation of ChREBP.

  16. Characterization of Thermobifida fusca cutinase-carbohydrate-binding module fusion proteins and their potential application in bioscouring.

    PubMed

    Zhang, Yao; Chen, Sheng; Xu, Meng; Cavaco-Paulo, Artur; Cavoco-Paulo, Artur; Wu, Jing; Chen, Jian

    2010-10-01

    Cutinase from Thermobifida fusca is thermally stable and has potential application in the bioscouring of cotton in the textile industry. In the present study, the carbohydrate-binding modules (CBMs) from T. fusca cellulase Cel6A (CBM(Cel6A)) and Cellulomonas fimi cellulase CenA (CBM(CenA)) were fused, separately, to the carboxyl terminus of T. fusca cutinase. Both fusion enzymes, cutinase-CBM(Cel6A) and cutinase-CBM(CenA), were expressed in Escherichia coli and purified to homogeneity. Enzyme characterization showed that both displayed similar catalytic properties and pH stabilities in response to T. fusca cutinase. In addition, both fusion proteins displayed an activity half-life of 53 h at their optimal temperature of 50°C. Compared to T. fusca cutinase, in the absence of pectinase, the binding activity on cotton fiber was enhanced by 2% for cutinase-CBM(Cel6A) and by 28% for cutinase-CBM(CenA), whereas in the presence of pectinase, the binding activity was enhanced by 40% for the former and 45% for the latter. Notably, a dramatic increase of up to 3-fold was observed in the amount of released fatty acids from cotton fiber by both cutinase-CBM fusion proteins when acting in concert with pectinase. This is the first report of improving the scouring efficiency of cutinase by fusing it with CBM. The improvement in activity and the strong synergistic effect between the fusion proteins and pectinase suggest that they may have better applications in textile bioscouring than the native cutinase. PMID:20729325

  17. Altering fatty acid availability does not impair prolonged, continuous running to fatigue: evidence for carbohydrate dependence.

    PubMed

    Leckey, Jill J; Burke, Louise M; Morton, James P; Hawley, John A

    2016-01-15

    We determined the effect of suppressing lipolysis via administration of nicotinic acid (NA) on fuel substrate selection and half-marathon running capacity. In a single-blinded, Latin square design, 12 competitive runners completed four trials involving treadmill running until volitional fatigue at a pace based on 95% of personal best half-marathon time. Trials were completed in a fed or overnight fasted state: 1) carbohydrate (CHO) ingestion before (2 g CHO·kg(-1)·body mass(-1)) and during (44 g/h) [CFED]; 2) CFED plus NA ingestion [CFED-NA]; 3) fasted with placebo ingestion during [FAST]; and 4) FAST plus NA ingestion [FAST-NA]. There was no difference in running distance (CFED, 21.53 ± 1.07; CFED-NA, 21.29 ± 1.69; FAST, 20.60 ± 2.09; FAST-NA, 20.11 ± 1.71 km) or time to fatigue between the four trials. Concentrations of plasma free fatty acids (FFA) and glycerol were suppressed following NA ingestion irrespective of preexercise nutritional intake but were higher throughout exercise in FAST compared with all other trials (P < 0.05). Rates of whole-body CHO oxidation were unaffected by NA ingestion in the CFED and FAST trials, but were lower in the FAST trial compared with the CFED-NA trial (P < 0.05). CHO was the primary substrate for exercise in all conditions, contributing 83-91% to total energy expenditure with only a small contribution from fat-based fuels. Blunting the exercise-induced increase in FFA via NA ingestion did not impair intense running capacity lasting ∼85 min, nor did it alter patterns of substrate oxidation in competitive athletes. Although there was a small but obligatory use of fat-based fuels, the oxidation of CHO-based fuels predominates during half-marathon running.

  18. Impact of the core components of the phosphoenolpyruvate-carbohydrate phosphotransferase system, HPr and EI, on differential protein expression in Ralstonia eutropha H16.

    PubMed

    Kaddor, Chlud; Voigt, Birgit; Hecker, Michael; Steinbüchel, Alexander

    2012-07-01

    In Ralstonia eutropha H16, seven genes encoding proteins being involved in the phosphoenolpyruvate-carbohydrate phosphotransferase system (PEP-PTS) were identified. In order to provide more insights into the poly(3-hydroxybutyrate) (PHB)-leaky phenotype of the HPr/EI deletion mutants H16ΔptsH, H16ΔptsI, and H16ΔptsHI when grown on the non-PTS substrate gluconate, parallel fermentations for comparison of their growth behavior were performed. Samples from the exponential, the early stationary, and late stationary growth phases were investigated by microscopy, gas chromatography and (phospho-) proteome analysis. A total of 71 differentially expressed proteins were identified using 2D-PAGE, Pro-Q Diamond and Coomassie staining, and MALDI-TOF analysis. Detected proteins were classified into five major functional groups: carbon metabolism, energy metabolism, amino acid metabolism, translation, and membrane transport/outer membrane proteins. Proteome analyses revealed enhanced expression of proteins involved in the Entner-Doudoroff pathway and in subsequent reactions in cells of strain H16 compared to the mutant H16ΔptsHI. Furthermore, proteins involved in PHB accumulation showed increased abundance in the wild-type. This expression pattern allowed us to identify proteins affecting carbon metabolism/PHB biosynthesis in strain H16 and translation/amino acid metabolism in strain H16ΔptsHI, and to gain insight into the molecular response of R. eutropha to the deletion of HPr/EI. PMID:22630130

  19. Coingestion of protein with carbohydrate during recovery from endurance exercise stimulates skeletal muscle protein synthesis in humans.

    PubMed

    Howarth, Krista R; Moreau, Natalie A; Phillips, Stuart M; Gibala, Martin J

    2009-04-01

    Coingestion of protein with carbohydrate (CHO) during recovery from exercise can affect muscle glycogen synthesis, particularly if CHO intake is suboptimal. Another potential benefit of protein feeding is an increased synthesis rate of muscle proteins, as is well documented after resistance exercise. In contrast, the effect of nutrient manipulation on muscle protein kinetics after aerobic exercise remains largely unexplored. We tested the hypothesis that ingesting protein with CHO after a standardized 2-h bout of cycle exercise would increase mixed muscle fractional synthetic rate (FSR) and whole body net protein balance (WBNB) vs. trials matched for total CHO or total energy intake. We also examined whether postexercise glycogen synthesis could be enhanced by adding protein or additional CHO to a feeding protocol that provided 1.2 g CHO x kg(-1) x h(-1), which is the rate generally recommended to maximize this process. Six active men ingested drinks during the first 3 h of recovery that provided either 1.2 g CHO.kg(-1).h(-1) (L-CHO), 1.2 g CHO + 0.4 g protein x kg(-1) x h(-1) (PRO-CHO), or 1.6 g CHO x kg(-1) x h(-1) (H-CHO) in random order. Based on a primed constant infusion of l-[ring-(2)H(5)]phenylalanine, analysis of biopsies (vastus lateralis) obtained at 0 and 4 h of recovery showed that muscle FSR was higher (P < 0.05) in PRO-CHO (0.09 +/- 0.01%/h) vs. both L-CHO (0.07 +/- 0.01%/h) and H-CHO (0.06 +/- 0.01%/h). WBNB assessed using [1-(13)C]leucine was positive only during PRO-CHO, and this was mainly attributable to a reduced rate of protein breakdown. Glycogen synthesis rate was not different between trials. We conclude that ingesting protein with CHO during recovery from aerobic exercise increased muscle FSR and improved WBNB, compared with feeding strategies that provided CHO only and were matched for total CHO or total energy intake. However, adding protein or additional CHO to a feeding strategy that provided 1.2 g CHO x kg(-1) x h(-1) did not further

  20. Metabolism and Fatty Acid Profile in Fat and Lean Rainbow Trout Lines Fed with Vegetable Oil: Effect of Carbohydrates

    PubMed Central

    Kamalam, Biju Sam; Médale, Françoise; Larroquet, Laurence; Corraze, Geneviève; Panserat, Stephane

    2013-01-01

    The present study investigated the effect of dietary carbohydrates on metabolism, with special focus on fatty acid bioconversion and flesh lipid composition in two rainbow trout lines divergently selected for muscle lipid content and fed with vegetable oils. These lines were chosen based on previously demonstrated potential differences in LC-PUFA synthesis and carbohydrate utilization. Applying a factorial study design, juvenile trout from the lean (L) and the fat (F) line were fed vegetable oil based diets with or without gelatinised starch (17.1%) for 12 weeks. Blood, liver, muscle, intestine and adipose tissue were sampled after the last meal. Feed intake and growth was higher in the L line than the F line, irrespective of the diet. Moderate postprandial hyperglycemia, strong induction of hepatic glucokinase and repressed glucose-6-phosphatase transcripts confirmed the metabolic response of both lines to carbohydrate intake. Further at the transcriptional level, dietary carbohydrate in the presence of n-3 LC-PUFA deficient vegetable oils enhanced intestinal chylomicron assembly, disturbed hepatic lipid metabolism and importantly elicited a higher response of key desaturase and elongase enzymes in the liver and intestine that endorsed our hypothesis. PPARγ was identified as the factor mediating this dietary regulation of fatty acid bioconversion enzymes in the liver. However, these molecular changes were not sufficient to modify the fatty acid composition of muscle or liver. Concerning the genotype effect, there was no evidence of substantial genotypic difference in lipid metabolism, LC-PUFA synthesis and flesh fatty acid profile when fed with vegetable oils. The minor reduction in plasma glucose and triglyceride levels in the F line was linked to potentially higher glucose and lipid uptake in the muscle. Overall, these data emphasize the importance of dietary macro-nutrient interface in evolving fish nutrition strategies. PMID:24124573

  1. Metabolism and fatty acid profile in fat and lean rainbow trout lines fed with vegetable oil: effect of carbohydrates.

    PubMed

    Kamalam, Biju Sam; Médale, Françoise; Larroquet, Laurence; Corraze, Geneviève; Panserat, Stephane

    2013-01-01

    The present study investigated the effect of dietary carbohydrates on metabolism, with special focus on fatty acid bioconversion and flesh lipid composition in two rainbow trout lines divergently selected for muscle lipid content and fed with vegetable oils. These lines were chosen based on previously demonstrated potential differences in LC-PUFA synthesis and carbohydrate utilization. Applying a factorial study design, juvenile trout from the lean (L) and the fat (F) line were fed vegetable oil based diets with or without gelatinised starch (17.1%) for 12 weeks. Blood, liver, muscle, intestine and adipose tissue were sampled after the last meal. Feed intake and growth was higher in the L line than the F line, irrespective of the diet. Moderate postprandial hyperglycemia, strong induction of hepatic glucokinase and repressed glucose-6-phosphatase transcripts confirmed the metabolic response of both lines to carbohydrate intake. Further at the transcriptional level, dietary carbohydrate in the presence of n-3 LC-PUFA deficient vegetable oils enhanced intestinal chylomicron assembly, disturbed hepatic lipid metabolism and importantly elicited a higher response of key desaturase and elongase enzymes in the liver and intestine that endorsed our hypothesis. PPARγ was identified as the factor mediating this dietary regulation of fatty acid bioconversion enzymes in the liver. However, these molecular changes were not sufficient to modify the fatty acid composition of muscle or liver. Concerning the genotype effect, there was no evidence of substantial genotypic difference in lipid metabolism, LC-PUFA synthesis and flesh fatty acid profile when fed with vegetable oils. The minor reduction in plasma glucose and triglyceride levels in the F line was linked to potentially higher glucose and lipid uptake in the muscle. Overall, these data emphasize the importance of dietary macro-nutrient interface in evolving fish nutrition strategies.

  2. Effects of vitamins, coenzymes and amino acids on reactions of homolytic cleavage of the O-glycoside bond in carbohydrates.

    PubMed

    Shadyro, O I; Kisel, R M; Vysotskii, V V; Edimecheva, I P

    2006-09-15

    It has been established that vitamins B1, K3 and C, coenzyme Q0 and amino acids cysteine and histidine effectively inhibit reactions of homolytic cleavage of the O-glycoside bond, which are responsible for the destruction of di- and polysaccharides on gamma-irradiation or the action of other reactive radical initiators. This effect was shown to originate from either oxidation or reduction of the radicals of carbohydrates undergoing destruction.

  3. Cloning, expression, purification, crystallization and preliminary X-ray diffraction analysis of the VP8* carbohydrate-binding protein of the human rotavirus strain Wa

    SciTech Connect

    Kraschnefski, Mark J.; Scott, Stacy A.; Holloway, Gavan; Coulson, Barbara S.; Itzstein, Mark von; Blanchard, Helen

    2005-11-01

    The carbohydrate-binding component (VP8*{sub 64–223}) of the human Wa rotavirus spike protein has been overexpressed in E. coli, purified and crystallized in two different crystal forms. X-ray diffraction data have been collected that have enabled determination of the Wa VP8*{sub 64–223} structure by molecular replacement. Rotaviruses exhibit host-specificity and the first crystallographic information on a rotavirus strain that infects humans is reported here. Recognition and attachment to host cells, leading to invasion and infection, is critically linked to the function of the outer capsid spike protein of the rotavirus particle. In some strains the VP8* component of the spike protein is implicated in recognition and binding of sialic-acid-containing cell-surface carbohydrates, thereby enabling infection by the virus. The cloning, expression, purification, crystallization and initial X-ray diffraction analysis of the VP8* core from human Wa rotavirus is reported. Two crystal forms (trigonal P3{sub 2}21 and monoclinic P2{sub 1}) have been obtained and X-ray diffraction data have been collected, enabling determination of the VP8*{sub 64–223} structure by molecular replacement.

  4. Metabolite Regulation of Nuclear Localization of Carbohydrate-response Element-binding Protein (ChREBP): ROLE OF AMP AS AN ALLOSTERIC INHIBITOR.

    PubMed

    Sato, Shogo; Jung, Hunmin; Nakagawa, Tsutomu; Pawlosky, Robert; Takeshima, Tomomi; Lee, Wan-Ru; Sakiyama, Haruhiko; Laxman, Sunil; Wynn, R Max; Tu, Benjamin P; MacMillan, John B; De Brabander, Jef K; Veech, Richard L; Uyeda, Kosaku

    2016-05-13

    The carbohydrate-response element-binding protein (ChREBP) is a glucose-responsive transcription factor that plays an essential role in converting excess carbohydrate to fat storage in the liver. In response to glucose levels, ChREBP is regulated by nuclear/cytosol trafficking via interaction with 14-3-3 proteins, CRM-1 (exportin-1 or XPO-1), or importins. Nuclear localization of ChREBP was rapidly inhibited when incubated in branched-chain α-ketoacids, saturated and unsaturated fatty acids, or 5-aminoimidazole-4-carboxamide ribonucleotide. Here, we discovered that protein-free extracts of high fat-fed livers contained, in addition to ketone bodies, a new metabolite, identified as AMP, which specifically activates the interaction between ChREBP and 14-3-3. The crystal structure showed that AMP binds directly to the N terminus of ChREBP-α2 helix. Our results suggest that AMP inhibits the nuclear localization of ChREBP through an allosteric activation of ChREBP/14-3-3 interactions and not by activation of AMPK. AMP and ketone bodies together can therefore inhibit lipogenesis by restricting localization of ChREBP to the cytoplasm during periods of ketosis. PMID:26984404

  5. Protein and carbohydrate intake influence sperm number and fertility in male cockroaches, but not sperm viability

    PubMed Central

    Bunning, Harriet; Rapkin, James; Belcher, Laurence; Archer, C. Ruth; Jensen, Kim; Hunt, John

    2015-01-01

    It is commonly assumed that because males produce many, tiny sperm, they are cheap to produce. Recent work, however, suggests that sperm production is not cost-free. If sperm are costly to produce, sperm number and/or viability should be influenced by diet, and this has been documented in numerous species. Yet few studies have examined the exact nutrients responsible for mediating these effects. Here, we quantify the effects of protein (P) and carbohydrate (C) intake on sperm number and viability in the cockroach Nauphoeta cinerea, as well as the consequences for male fertility. We found the intake of P and C influenced sperm number, being maximized at a high intake of diets with a P : C ratio of 1 : 2, but not sperm viability. The nutritional landscapes for male fertility and sperm number were closely aligned, suggesting that sperm number is the major determinant of male fertility in N. cinerea. Under dietary choice, males regulate nutrient intake at a P : C ratio of 1 : 4.95, which is midway between the ratios needed to maximize sperm production and pre-copulatory attractiveness in this species. This raises the possibility that males regulate nutrient intake to balance the trade-off between pre- and post-copulatory traits in this species. PMID:25608881

  6. The Roles of Vitamin A in the Regulation of Carbohydrate, Lipid, and Protein Metabolism

    PubMed Central

    Chen, Wei; Chen, Guoxun

    2014-01-01

    Currently, two-thirds of American adults are overweight or obese. This high prevalence of overweight/obesity negatively affects the health of the population, as obese individuals tend to develop several chronic diseases, such as type 2 diabetes and cardiovascular diseases. Due to obesity’s impact on health, medical costs, and longevity, the rise in the number of obese people has become a public health concern. Both genetic and environmental/dietary factors play a role in the development of metabolic diseases. Intuitively, it seems to be obvious to link over-nutrition to the development of obesity and other metabolic diseases. However, the underlying mechanisms are still unclear. Dietary nutrients not only provide energy derived from macronutrients, but also factors such as micronutrients with regulatory roles. How micronutrients, such as vitamin A (VA; retinol), regulate macronutrient homeostasis is still an ongoing research topic. As an essential micronutrient, VA plays a key role in the general health of an individual. This review summarizes recent research progress regarding VA’s role in carbohydrate, lipid, and protein metabolism. Due to the large amount of information regarding VA functions, this review focusses on metabolism in metabolic active organs and tissues. Additionally, some perspectives for future studies will be provided. PMID:26237385

  7. Quantitative assessment of the multivalent protein-carbohydrate interactions on silicon.

    PubMed

    Yang, Jie; Chazalviel, Jean-Noël; Siriwardena, Aloysius; Boukherroub, Rabah; Ozanam, François; Szunerits, Sabine; Gouget-Laemmel, Anne Chantal

    2014-10-21

    A key challenge in the development of glycan arrays is that the sensing interface be fabricated reliably so as to ensure the sensitive and accurate analysis of the protein-carbohydrate interaction of interest, reproducibly. These goals are complicated in the case of glycan arrays as surface sugar density can influence dramatically the strength and mode of interaction of the sugar ligand at any interface with lectin partners. In this Article, we describe the preparation of carboxydecyl-terminated crystalline silicon (111) surfaces onto which are grafted either mannosyl moieties or a mixture of mannose and spacer alcohol molecules to provide "diluted" surfaces. The fabrication of the silicon surfaces was achieved efficiently through a strategy implicating a "click" coupling step. The interactions of these newly fabricated glycan interfaces with the lectin, Lens culinaris, have been characterized using quantitative infrared (IR) spectroscopy in the attenuated total geometry (ATR). The density of mannose probes and lectin targets was precisely determined for the first time by the aid of special IR calibration experiments, thus allowing for the interpretation of the distribution of mannose and its multivalent binding with lectins. These experimental findings were accounted for by numerical simulations of lectin adsorption. PMID:25216376

  8. Reassessing the role of protein-carbohydrate complementarity during sperm-egg interactions in the mouse

    PubMed Central

    SHUR, BARRY D.

    2009-01-01

    Despite years of intense study by many investigators, it may appear that we have made little progress towards a molecular understanding of mammalian sperm binding to the egg zona pellucida. An abundance of evidence derived from in vitro assays suggests that sperm-zona pellucida binding is dependent upon sperm recognition of specific glycan moieties on the zona pellucida glycoproteins. However, there is considerable disagreement regarding the identity of the zona pellucida sugars thought to mediate sperm binding, as well as disagreement over the identity of the sperm receptors themselves. Moreover, results from in vivo gene-targeting strategies fail to support a role for many, if not all, of the sperm receptors and their zona pellucida ligands implicated from in vitro assays. Nevertheless, a retrospective view of the literature suggests that some common principles are emerging regarding the molecular basis of mammalian sperm-zona binding, both with respect to the nature of the components that mediate binding, as well as the involvement of distinct receptor-ligand interactions, that involve both protein- and carbohydrate-dependent mechanisms of binding. PMID:18649283

  9. Protein and carbohydrate intake influence sperm number and fertility in male cockroaches, but not sperm viability.

    PubMed

    Bunning, Harriet; Rapkin, James; Belcher, Laurence; Archer, C Ruth; Jensen, Kim; Hunt, John

    2015-03-01

    It is commonly assumed that because males produce many, tiny sperm, they are cheap to produce. Recent work, however, suggests that sperm production is not cost-free. If sperm are costly to produce, sperm number and/or viability should be influenced by diet, and this has been documented in numerous species. Yet few studies have examined the exact nutrients responsible for mediating these effects. Here, we quantify the effects of protein (P) and carbohydrate (C) intake on sperm number and viability in the cockroach Nauphoeta cinerea, as well as the consequences for male fertility. We found the intake of P and C influenced sperm number, being maximized at a high intake of diets with a P : C ratio of 1 : 2, but not sperm viability. The nutritional landscapes for male fertility and sperm number were closely aligned, suggesting that sperm number is the major determinant of male fertility in N. cinerea. Under dietary choice, males regulate nutrient intake at a P : C ratio of 1 : 4.95, which is midway between the ratios needed to maximize sperm production and pre-copulatory attractiveness in this species. This raises the possibility that males regulate nutrient intake to balance the trade-off between pre- and post-copulatory traits in this species.

  10. Effects of immediate postexercise carbohydrate ingestion with and without protein on neutrophil degranulation.

    PubMed

    Costa R, J S; Walters, Robert; Bilzon J, L J; Walsh, Neil P

    2011-06-01

    The purpose of the study was to determine the effects of carbohydrate (CHO) intake, with and without protein (PRO), immediately after prolonged strenuous exercise on circulating bacterially stimulated neutrophil degranulation. Twelve male runners completed 3 feeding interventions, 1 week apart, in randomized order after 2 hr of running at 75% VO2max. The feeding interventions included a placebo solution, a CHO solution equal to 1.2 g CHO/kg body mass (BM), and a CHO-PRO solution equal to 1.2 g CHO/kg BM and 0.4 g PRO/kg BM (CHO+PRO) immediately postexercise. All solutions were flavor and water-volume equivalent (12 ml/kg BM). Circulating leukocyte counts, bacterially stimulated neutrophil degranulation, plasma insulin, and cortisol were determined from blood samples collected preexercise, immediately postexercise, and every 30 min until 180 min postexercise. The immediate postexercise circulating leukocytosis, neutrophilia, and lymphocytosis (p < .01 vs. preexercise) and the delayed lymphopenia (90 min postexercise, p < .05 vs. preexercise) were similar on all trials. Bacterially stimulated neutrophil degranulation decreased during recovery in control (23% at 180 min, p < .01 vs. preexercise) but remained above preexercise levels with CHO and CHO+PRO. In conclusion, CHO ingestion, with or without PRO, immediately after prolonged strenuous exercise prevented the decrease in bacterially stimulated neutrophil degranulation during recovery. PMID:21719901

  11. Effects of Salt Stress on Amino Acid, Organic Acid, and Carbohydrate Composition of Roots, Bacteroids, and Cytosol of Alfalfa (Medicago sativa L.) 1

    PubMed Central

    Fougère, Francoise; Le Rudulier, Daniel; Streeter, John G.

    1991-01-01

    Ethanol-soluble organic acid, carbohydrate, and amino acid constituents of alfalfa (Medicago sativa) roots and nodules (cytosol and bacteroids) have been identified by gas-liquid chromatography and high performance liquid chromatography. Among organic acids, citrate was the predominant compound in roots and cytosol, with malonate present in the highest concentration in bacteroids. These two organic acids together with malate and succinate accounted for more than 85% of the organic acid pool in nodules and for 97% in roots. The major carbohydrates in roots, nodule cytosol, and bacteroids were (descending order of concentration): sucrose, pinitol, glucose, and ononitol. Maltose and trehalose appeared to be present in very low concentrations. Asparagine, glutamate, alanine, γ-aminobutyrate, and proline were the major amino acids in cytosol and bacteroids. In addition to these solutes, serine and glutamine were well represented in roots. When alfalfa plants were subjected to 0.15 m sodium chloride stress for 2 weeks, total organic acid concentration in nodules and roots were depressed by more than 40%, whereas lactate concentration increased by 11, 27, and 94% in cytosol, roots, and bacteroids, respectively. In bacteroids, lactate became the most abundant organic acid and might contribute partly to the osmotic adjustment. On the other hand, salt stress induced a large increase in the amino acid and carbohydrate pools. Within the amino acids, proline showed the largest increase, 11.3-, 12.8-, and 8.0-fold in roots, cytosol, and bacteroids, respectively. Its accumulation reflected an osmoregulatory mechanism not only in roots but also in nodule tissue. In parallel, asparagine concentration was greatly enhanced; this amide remained the major nitrogen solute and, in bacteroids, played a significant role in osmoregulation. On the contrary, the salt treatment had a very limited effect on the concentration of other amino acids. Among carbohydrates, pinitol concentration was

  12. Metabolic determinants of body weight after cats were fed a low-carbohydrate high-protein diet or a high-carbohydrate low-protein diet ad libitum for 8 wk.

    PubMed

    Coradini, M; Rand, J S; Morton, J M; Rawlings, J M

    2014-10-01

    Overweight and obese conditions are common in cats and are associated with the development of a number of diseases. Knowledge of metabolic determinants and predictors of weight gain may enable better preventative strategies for obesity in cats. Lean, healthy cats were fed either a low-carbohydrate high-protein diet (n 16) or a high-carbohydrate low-protein (n 16) diet ad libitum for 8 wk. Potential determinants and predictors of final body weight assessed were body fat and lean masses, energy required for maintenance, energy requirements above maintenance for each kilogram of weight gain, insulin sensitivity index, fasting, mean 24-h and peak plasma glucose, insulin, and leptin concentrations, and fasting and mean 24-h serum adiponectin concentrations. In cats fed the low-carbohydrate high-protein diet, after adjusting for initial body weight, those with higher energy requirements for weight gain and higher fasting glucose concentration had higher final body weights (P ≤ 0.01). Predicted final body weights using initial body weight, fasting glucose and mean 24-h insulin concentrations (partial R(2) 37.3%) were imprecise. An equation using just initial body weight and fasting glucose concentration would be of more practical value, but was marginally less precise. In cats fed the high-carbohydrate low-protein diet, those with lower fasting leptin concentration initially had higher final body weights (P = 0.01). Predicted final body weights using initial body weight, energy requirements for maintenance, total body fat percentage and fasting leptin concentration (partial R(2) 39.2%) were reasonably precise. Further studies are warranted to confirm these findings and to improve the precision of predicted final body weights. PMID:25084314

  13. Metabolic determinants of body weight after cats were fed a low-carbohydrate high-protein diet or a high-carbohydrate low-protein diet ad libitum for 8 wk.

    PubMed

    Coradini, M; Rand, J S; Morton, J M; Rawlings, J M

    2014-10-01

    Overweight and obese conditions are common in cats and are associated with the development of a number of diseases. Knowledge of metabolic determinants and predictors of weight gain may enable better preventative strategies for obesity in cats. Lean, healthy cats were fed either a low-carbohydrate high-protein diet (n 16) or a high-carbohydrate low-protein (n 16) diet ad libitum for 8 wk. Potential determinants and predictors of final body weight assessed were body fat and lean masses, energy required for maintenance, energy requirements above maintenance for each kilogram of weight gain, insulin sensitivity index, fasting, mean 24-h and peak plasma glucose, insulin, and leptin concentrations, and fasting and mean 24-h serum adiponectin concentrations. In cats fed the low-carbohydrate high-protein diet, after adjusting for initial body weight, those with higher energy requirements for weight gain and higher fasting glucose concentration had higher final body weights (P ≤ 0.01). Predicted final body weights using initial body weight, fasting glucose and mean 24-h insulin concentrations (partial R(2) 37.3%) were imprecise. An equation using just initial body weight and fasting glucose concentration would be of more practical value, but was marginally less precise. In cats fed the high-carbohydrate low-protein diet, those with lower fasting leptin concentration initially had higher final body weights (P = 0.01). Predicted final body weights using initial body weight, energy requirements for maintenance, total body fat percentage and fasting leptin concentration (partial R(2) 39.2%) were reasonably precise. Further studies are warranted to confirm these findings and to improve the precision of predicted final body weights.

  14. Impact of glucose polymer chain length on heat and physical stability of milk protein-carbohydrate nutritional beverages.

    PubMed

    Chen, Biye; O'Mahony, James A

    2016-11-15

    This study investigated the impact of glucose polymer chain length on heat and physical stability of milk protein isolate (MPI)-carbohydrate nutritional beverages containing 8.5% w/w total protein and 5% w/w carbohydrate. The maltodextrin and corn syrup solids glucose polymers used had dextrose equivalent (DE) values of 17 or 38, respectively. Increasing DE value of the glucose polymers resulted in a greater increase in brown colour development, ionic calcium, protein particle size, apparent viscosity and pseudoplastic rheological behaviour, and greater reduction in pH, hydration and heat stability on sterilisation at 120°C. Incorporation of glucose polymers with MPI retarded sedimentation of protein during accelerated physical stability testing, with maltodextrin DE17 causing a greater reduction in sedimentation velocity and compressibility of sediment formed than corn syrup solids DE38. The results demonstrate that chain length of the glucose polymer used strongly impacts heat and physical stability of MPI-carbohydrate nutritional beverages. PMID:27283657

  15. The influence of commercially-available carbohydrate and carbohydrate-protein supplements on endurance running performance in recreational athletes during a field trial

    PubMed Central

    2013-01-01

    Background It is recommended that endurance athletes consume carbohydrate (CHO) supplements, providing 6-8% CHO concentration, during exercise > 60 minutes to improve athletic performance. Recently research has compared carbohydrate-protein (CHO-P) supplementation to the traditionally used CHO supplementation during endurance exercise, following these supplementation recommendations, in controlled settings, but not under simulated applied conditions such as a field trial. Therefore, the purpose of the present investigation was to test CHO and CHO-P supplementation under applied conditions such that commercially-available isocaloric (CHO-P & double-carbohydrate [CHO-CHO]) and isocarbohydrate (CHO-P & CHO) supplements were compared to a placebo (PLA), within an outdoor running field trial > 60 minutes in order to asses their influence on endurance performance. Methods Twelve male recreational runners completed four, 19.2 km runs, where they were instructed to run at a pace similar to race pace including a final sprint to the finish, which in this case was the final two laps of the course (1.92 km). Supplementation was provided before the start and in 4 km increments. Performance was measured by time to complete the 19.2 km run and last 1.92 km sprint. Results Analyses found no difference between supplements in time to complete the 19.2 km run (PLA = 88.6 ± 11.6 min, CHO = 89.1 ± 11.3 min, CHO-P = 89.1 ± 11.8 min, CHO-CHO = 89.6 ± 11.9 min) or last 1.92 km sprint to the finish (PLA = 8.3 ± 1.2 min, CHO = 8.2 ± 1.2 min, CHO-P = 8.2 ± 1.2 min, CHO-CHO = 8.4 ± 1.5 min). Conclusions When following recommendation for supplementation within a field trial, commercially available CHO and CHO-P supplements do not appear to enhance performance in male recreational runners. PMID:23537142

  16. Effects of adult-derived carbohydrates, amino acids and micronutrients on female reproduction in a fruit-feeding butterfly.

    PubMed

    Bauerfeind, Stephanie S; Fischer, Klaus

    2005-05-01

    It is generally believed that butterflies (and other holometabolous insects) rely primarily on reserves accumulated during the larval stage for reproduction, whereas the carbohydrate-rich adult diet is thought to mainly cover energy requirements. In at least some species though, realization of the full reproductive potential is extensively affected by post-eclosion nutrition. While the importance of carbohydrates is fairly well understood, the role of adult-derived amino acids and micronutrients is controversial and largely unknown, respectively. We here focus on the effects of different adult diets on female reproduction in the tropical, fruit-feeding butterfly Bicyclus anynana (Nymphalidae). Carbohydrates were the most important adult-derived nutrients affecting reproduction. Adding amino acids, vitamins or minerals to sucrose-based solutions did not yield a reproductive output equivalent to that of fruit-fed females, which showed the highest performance throughout. This suggests that either not yet identified compounds of fruit substantially contribute to reproduction, or that resource congruence (the use of nutrient types in a specified ratio) rather than any specific nutrient component is of key importance. Apart from adult income, realized fecundity depended on egg size and longevity, with the former dominating when dietary quality was low, but the latter when quality was high. Thus, the egg size-number trade-off seems to be affected by female nutrition.

  17. A photo-cleavable biotin affinity tag for the facile release of a photo-crosslinked carbohydrate-binding protein.

    PubMed

    Chang, Tsung-Che; Adak, Avijit K; Lin, Ting-Wei; Li, Pei-Jhen; Chen, Yi-Ju; Lai, Chain-Hui; Liang, Chien-Fu; Chen, Yu-Ju; Lin, Chun-Cheng

    2016-03-15

    The use of photo-crosslinking glycoprobes represents a powerful strategy for the covalent capture of labile protein complexes and allows detailed characterization of carbohydrate-mediated interactions. The selective release of target proteins from solid support is a key step in functional proteomics. We envisaged that light activation can be exploited for releasing labeled protein in a dual photo-affinity probe-based strategy. To investigate this possibility, we designed a trifunctional, galactose-based, multivalent glycoprobe for affinity labeling of carbohydrate-binding proteins. The resulting covalent protein-probe adduct is attached to a photo-cleavable biotin affinity tag; the biotin moiety enables specific presentation of the conjugate on streptavidin-coated beads, and the photolabile linker allows the release of the labeled proteins. This dual probe promotes both the labeling and the facile cleavage of the target protein complexes from the solid surfaces and the remainder of the cell lysate in a completely unaltered form, thus eliminating many of the common pitfalls associated with traditional affinity-based purification methods.

  18. Low and high dietary protein:carbohydrate ratios during pregnancy affect materno-fetal glucose metabolism in pigs.

    PubMed

    Metges, Cornelia C; Görs, Solvig; Lang, Iris S; Hammon, Harald M; Brüssow, Klaus-Peter; Weitzel, Joachim M; Nürnberg, Gerd; Rehfeldt, Charlotte; Otten, Winfried

    2014-02-01

    Inadequate dietary protein during pregnancy causes intrauterine growth retardation. Whether this is related to altered maternal and fetal glucose metabolism was examined in pregnant sows comparing a high-protein:low-carbohydrate diet (HP-LC; 30% protein, 39% carbohydrates) with a moderately low-protein:high-carbohydrate diet (LP-HC; 6.5% protein, 68% carbohydrates) and the isoenergetic standard diet (ST; 12.1% protein, 60% carbohydrates). During late pregnancy, maternal and umbilical glucose metabolism and fetal hepatic mRNA expression of gluconeogenic enzymes were examined. During an i.v. glucose tolerance test (IVGTT), the LP-HC-fed sows had lower insulin concentrations and area under the curve (AUC), and higher glucose:insulin ratios than the ST- and the HP-LC-fed sows (P < 0.05). Insulin sensitivity and glucose clearance were higher in the LP-HC sows compared with ST sows (P < 0.05). Glucagon concentrations during postabsorptive conditions and IVGTT, and glucose AUC during IVGTT, were higher in the HP-LC group compared with the other groups (P < 0.001). (13)C glucose oxidation was lower in the HP-LC sows than in the ST and LP-HC sows (P < 0.05). The HP-LC fetuses were lighter and had a higher brain:liver ratio than the ST group (P < 0.05). The umbilical arterial inositol concentration was greater in the HP-LC group (P < 0.05) and overall small fetuses (230-572 g) had higher values than medium and heavy fetuses (≥573 g) (P < 0.05). Placental lactate release was lower in the LP-HC group than in the ST group (P < 0.05). Fetal glucose extraction tended to be lower in the LP-HC group than in the ST group (P = 0.07). In the HP-LC and LP-HC fetuses, hepatic mRNA expression of cytosolic phosphoenolpyruvate carboxykinase (PCK1) and glucose-6-phosphatase (G6PC) was higher than in the ST fetuses (P < 0.05). In conclusion, the HP-LC and LP-HC sows adapted by reducing glucose turnover and oxidation and having higher glucose utilization, respectively. The HP-LC and LP

  19. Lower Protein-to-Carbohydrate Ratio in Maternal Diet is Associated with Higher Childhood Systolic Blood Pressure up to Age Four Years.

    PubMed

    Blumfield, Michelle L; Nowson, Caryl; Hure, Alexis J; Smith, Roger; Simpson, Stephen J; Raubenheimer, David; MacDonald-Wicks, Lesley; Collins, Clare E

    2015-05-01

    The prenatal environment can influence development of offspring blood pressure (BP), which tracks into adulthood. This prospective longitudinal study investigated whether maternal pregnancy dietary intake is associated with the development of child BP up to age four years. Data are from 129 mother-child dyads enrolled in the Women and Their Children's Health study. Maternal diet was assessed using a validated 74-item food frequency questionnaire at 18 to 24 weeks and 36 to 40 weeks, with a reference period of the previous three months. Child systolic and diastolic BP were measured at 3, 6, 9, 12, 24, 36 and 48 months, using an automated BP monitor. Using mixed-model regression analyses adjusted for childhood growth indices, pregnancy intakes of percentage of energy (E%) polyunsaturated fat (β coefficient 0.73; 95% CI 0.003, 1.45; p = 0.045), E% omega-6 fatty acids (β coefficient 0.89; 95% CI 0.09, 1.69; p = 0.03) and protein-to-carbohydrate (P:C) ratio (β coefficient -14.14; 95% CI -27.68, -0.60; p = 0.04) were associated with child systolic BP trajectory up to 4 years. Child systolic BP was greatest at low proportions of dietary protein (<16% of energy) and high carbohydrate (>40% of energy) intakes. There may be an ideal maternal macronutrient ratio associated with optimal infant BP. Maternal diet, which is potentially modifiable, may play an important role in influencing offspring risk of future hypertension.

  20. Protein, carbohydrate, lipid concentrations and HSP 70-HSP 90 (stress protein) expression over an annual cycle: useful tools to detect feeding constraints in a benthic suspension feeder

    NASA Astrophysics Data System (ADS)

    Rossi, Sergio; Snyder, Mark J.; Gili, Josep-Marìa

    2006-03-01

    In the present paper we suggest an effect of seasonal variations in food availability on two ecophysiological parameters in a warm temperate benthic suspension feeder: the tissue concentrations of proteins, carbohydrates and lipids on the one hand, and the expression of stress proteins (HSP 70 and 90, inducible and/or constitutive) on the other hand. The concentrations of biomacromolecules have already been used to describe bentho-pelagic and reproductive processes, but this is the first time that stress protein expression is suggested to be directly related with food constraints in marine organisms. Paramuricea clavata (Cnidaria: Gorgonacea) express HSP 70 and 90 (constitutive and/or inducible) throughout the seasonal cycle, and HSP 70 levels are twice as high as the levels of HSP 90. In summer and autumn, when seston availability to suspension feeders was low, P. clavata showed low levels of carbohydrates and lipids, but high levels of HSPs expression. The levels of HSP 70 and 90 expression fit with negative exponential functions of carbohydrate and lipid concentrations. We suggest a direct effect of food availability on the studied ecophysiological parameters while the effect of temperature may be rather indirect. HSP expression as well as the tissue concentrations of carbohydrate and lipids may be used as biomarkers of environmental changes and seston availability to benthic suspension feeders.

  1. Protein biosynthesis with conformationally restricted amino acids

    SciTech Connect

    Mendel, D. Lawrence Berkeley Lab., CA ); Ellman, J.; Schultz, P.G. )

    1993-05-19

    The incorporation of conformationally constrained amino acids into peptides is a powerful approach for generating structurally defined peptides as conformational probes and bioactive agents. The ability to site-specifically introduce constrained amino acids into large polypeptide chains would provide a similar opportunity to probe the flexibility, conformation, folding and stability of proteins. To this end, we have examined the competence of the Escherichia coli protein biosynthetic machinery to incorporate a number of these unnatural amino acids into the 164 residue protein T4 lysozyme (T4L). Results clearly demonstrate that the protein biosynthetic machinery can accommodate a wide variety of conformationally constrained amino acids. The expansion of structural motifs that can be biosynthetically incorporated into proteins to include a large number of conformationally constrained amino acids significantly increases the power of mutagenesis methods as probes of protein structure and function and provides additional insights into the steric requirements of the translational machinery. 13 refs., 2 figs.

  2. Combined carbohydrate-protein supplementation improves competitive endurance exercise performance in the heat.

    PubMed

    Cathcart, Andrew J; Murgatroyd, Scott R; McNab, Alison; Whyte, Laura J; Easton, Chris

    2011-09-01

    Laboratory-based studies have demonstrated that adding protein (PRO) to a carbohydrate (CHO) supplement can improve thermoregulatory capacity, exercise performance and recovery. However, no study has investigated these effects in a competitive sporting context. This study assessed the effects of combined CHO-PRO supplementation on physiological responses and exercise performance during 8 days of strenuous competition in a hot environment. Twenty-eight cyclists participating in the TransAlp mountain bike race were randomly assigned to fitness-matched placebo (PLA 76 g L(-1) CHO) or CHO-PRO (18 g L(-1) PRO, 72 g L(-1) CHO) groups. Participants were given enough supplements to allow ad libitum consumption. Physiological and anthropometric variables were recorded pre- and post-exercise. Body mass decreased significantly from race stage 1 to 8 in the PLA group (-0.75 ± 0.22 kg, P = 0.01) but did not change in the CHO-PRO group (0.42 ± 0.42 kg, P = 0.35). Creatine kinase concentration and muscle soreness were substantially elevated during the race, but were not different between groups (P = 0.82, P = 0.44, respectively). Urine osmolality was significantly higher in the CHO-PRO versus the PLA group (P = 0.04) and the rise in tympanic temperature from pre- to post-exercise was significantly less in CHO-PRO versus PLA (P = 0.01). The CHO-PRO group also completed the 8 stages significantly quicker than the PLA group (2,277 ± 127 vs. 2,592 ± 68 min, respectively, P = 0.02). CHO-PRO supplementation therefore appears to prevent body mass loss, enhance thermoregulatory capacity and improve competitive exercise performance despite no effect on muscle damage.

  3. Probing the Functions of Carbohydrate Binding Modules in the CBEL Protein from the Oomycete Phytophthora parasitica

    PubMed Central

    Martinez, Thomas; Texier, Hélène; Nahoum, Virginie; Lafitte, Claude; Cioci, Gianluca; Heux, Laurent; Dumas, Bernard; O’Donohue, Michael

    2015-01-01

    Oomycetes are microorganisms that are distantly related to true fungi and many members of this phylum are major plant pathogens. Oomycetes express proteins that are able to interact with plant cell wall polysaccharides, such as cellulose. This interaction is thought to be mediated by carbohydrate-binding modules that are classified into CBM family 1 in the CAZy database. In this study, the two CBMs (1–1 and 1–2) that form part of the cell wall glycoprotein, CBEL, from Phytophthora parasitica have been submitted to detailed characterization, first to better quantify their interaction with cellulose and second to determine whether these CBMs can be useful for biotechnological applications, such as biomass hydrolysis. A variety of biophysical techniques were used to study the interaction of the CBMs with various substrates and the data obtained indicate that CBEL’s CBM1-1 exhibits much greater cellulose binding ability than CBM1-2. Engineering of the family 11 xylanase from Talaromyces versatilis (TvXynB), an enzyme that naturally bears a fungal family 1 CBM, has produced two variants. The first one lacks its native CBM, whereas the second contains the CBEL CBM1-1. The study of these enzymes has revealed that wild type TvXynB binds to cellulose, via its CBM1, and that the substitution of its CBM by oomycetal CBM1-1 does not affect its activity on wheat straw. However, intriguingly the addition of CBEL during the hydrolysis of wheat straw actually potentiates the action of TvXynB variant lacking a CBM1. This suggests that the potentiating effect of CBM1-1 might not require the formation of a covalent linkage to TvXynB. PMID:26390127

  4. Development of a Smartphone Application to Capture Carbohydrate, Lipid, and Protein Contents of Daily Food

    PubMed Central

    Diouri, Omar; Place, Jerome; Traverso, Magali; Georgescu, Vera; Picot, Marie-Christine; Renard, Eric

    2015-01-01

    Background: Meal lipids (LIP) and proteins (PRO) may influence the effect of insulin doses based on carbohydrate (CHO) counting in patients with type 1 diabetes (T1D). We developed a smartphone application for CHO, LIP, and PRO counting in daily food and assessed its usability in real-life conditions and potential usefulness. Methods: Ten T1D patients used the android application for 1 week to collect their food intakes. Data included meal composition, premeal and 2-hour postmeal blood glucose, corrections for hypo- or hyperglycemia after meals, and time for entering meals in the application. Meal insulin doses were based on patients’ CHO counting (application in blinded mode). Linear mixed models were used to assess the statistical differences. Results: In all, 187 meals were analyzed. Average computed CHO amount was 74.37 ± 31.78 grams; LIP amount: 20.26 ± 14.28 grams and PRO amount: 25.68 ± 16.68 grams. Average CHO, LIP, and PRO contents were significantly different between breakfast and lunch/dinner. The average time for meal entry in the application moved from 3-4 minutes to 2.5 minutes during the week. No significant impact of LIP and PRO was found on available blood glucose values. Conclusion: Our study shows CHO, LIP, and PRO intakes can be easily captured by an application on smartphone for meal entry used by T1D patients. Although LIP and PRO meal contents did not influence glucose levels when insulin doses were based on CHO in this pilot study, this application could be used for further investigation of this topic, including in closed-loop conditions. PMID:26424241

  5. High-protein-low-carbohydrate diet: deleterious metabolic and cardiovascular effects depend on age.

    PubMed

    Bedarida, Tatiana; Baron, Stephanie; Vessieres, Emilie; Vibert, Francoise; Ayer, Audrey; Marchiol-Fournigault, Carmen; Henrion, Daniel; Paul, Jean-Louis; Noble, Florence; Golmard, Jean-Louis; Beaudeux, Jean-Louis; Cottart, Charles-Henry; Nivet-Antoine, Valerie

    2014-09-01

    High-protein-low-carbohydrate (HP-LC) diets have become widespread. Yet their deleterious consequences, especially on glucose metabolism and arteries, have already been underlined. Our previous study (2) has already shown glucose intolerance with major arterial dysfunction in very old mice subjected to an HP-LC diet. The hypothesis of this work was that this diet had an age-dependent deleterious metabolic and cardiovascular outcome. Two groups of mice, young and adult (3 and 6 mo old), were subjected for 12 wk to a standard or to an HP-LC diet. Glucose and lipid metabolism was studied. The cardiovascular system was explored from the functional stage with Doppler-echography to the molecular stage (arterial reactivity, mRNA, immunohistochemistry). Young mice did not exhibit any significant metabolic modification, whereas adult mice presented marked glucose intolerance associated with an increase in resistin and triglyceride levels. These metabolic disturbances were responsible for cardiovascular damages only in adult mice, with decreased aortic distensibility and left ventricle dysfunction. These seemed to be the consequence of arterial dysfunctions. Mesenteric arteries were the worst affected with a major oxidative stress, whereas aorta function seemed to be maintained with an appreciable role of cyclooxygenase-2 to preserve endothelial function. This study highlights for the first time the age-dependent deleterious effects of an HP-LC diet on metabolism, with glucose intolerance and lipid disorders and vascular (especially microvessels) and cardiac functions. This work shows that HP-LC lead to equivalent cardiovascular alterations, as observed in very old age, and underlines the danger of such diet.

  6. Distinguishing proteins from arbitrary amino acid sequences.

    PubMed

    Yau, Stephen S-T; Mao, Wei-Guang; Benson, Max; He, Rong Lucy

    2015-01-01

    What kinds of amino acid sequences could possibly be protein sequences? From all existing databases that we can find, known proteins are only a small fraction of all possible combinations of amino acids. Beginning with Sanger's first detailed determination of a protein sequence in 1952, previous studies have focused on describing the structure of existing protein sequences in order to construct the protein universe. No one, however, has developed a criteria for determining whether an arbitrary amino acid sequence can be a protein. Here we show that when the collection of arbitrary amino acid sequences is viewed in an appropriate geometric context, the protein sequences cluster together. This leads to a new computational test, described here, that has proved to be remarkably accurate at determining whether an arbitrary amino acid sequence can be a protein. Even more, if the results of this test indicate that the sequence can be a protein, and it is indeed a protein sequence, then its identity as a protein sequence is uniquely defined. We anticipate our computational test will be useful for those who are attempting to complete the job of discovering all proteins, or constructing the protein universe. PMID:25609314

  7. Counting carbohydrates

    MedlinePlus

    Carb counting; Carbohydrate-controlled diet; Diabetic diet; Diabetes-counting carbohydrates ... Many foods contain carbohydrates (carbs), including: Fruit and fruit juice Cereal, bread, pasta, and rice Milk and milk products, soy milk Beans, legumes, ...

  8. A Low-Protein, High-Carbohydrate Diet Stimulates Thermogenesis in the Brown Adipose Tissue of Rats via ATF-2.

    PubMed

    de França, Suélem A; dos Santos, Maísa P; Przygodda, Franciele; Garófalo, Maria Antonieta R; Kettelhut, Isis C; Magalhães, Diego A; Bezerra, Kalinne S; Colodel, Edson M; Flouris, Andreas D; Andrade, Cláudia M B; Kawashita, Nair H

    2016-03-01

    The aim of this study was to evaluate thermogenesis in the interscapular brown adipose tissue (IBAT) of rats submitted to low-protein, high-carbohydrate (LPHC) diet and the involvement of adrenergic stimulation in this process. Male rats (~100 g) were submitted to LPHC (6%-protein; 74%-carbohydrate) or control (C; 17%-protein; 63%-carbohydrate) isocaloric diets for 15 days. The IBAT temperature was evaluated in the rats before and after the administration of noradrenaline (NA) (20 µg 100 g b w(-1) min(-1)). The expression levels of uncoupling protein 1 (UCP1) and other proteins involved in the regulation of UCP1 expression were determined by Western blot (Student's t test, P ≤ 0.05). The LPHC diet promoted a 1.1 °C increase in the basal temperature of IBAT when compared with the basal temperature in the IBAT of the C group. NA administration promoted a 0.3 °C increase in basal temperature in the IBAT of the C rats and a 0.5 °C increase in the IBAT of the LPHC group. The level of UCP1 increased 60% in the IBAT of LPHC-fed rats, and among the proteins involved in its expression, such as β3-AR and α1-AR, there was a 40% increase in the levels of p38-MAPK and a 30% decrease in CREB when compared to the C rats. The higher sympathetic flux to IBAT, which is a consequence of the administration of the LPHC diet to rats, activates thermogenesis and increases the expression of UCP1 in the tissue. Our results suggest that the increase in UCP1 content may occur via p38 MAPK and ATF2.

  9. Complete amino acid sequence and structure characterization of the taste-modifying protein, miraculin.

    PubMed

    Theerasilp, S; Hitotsuya, H; Nakajo, S; Nakaya, K; Nakamura, Y; Kurihara, Y

    1989-04-25

    The taste-modifying protein, miraculin, has the unusual property of modifying sour taste into sweet taste. The complete amino acid sequence of miraculin purified from miracle fruits by a newly developed method (Theerasilp, S., and Kurihara, Y. (1988) J. Biol. Chem. 263, 11536-11539) was determined by an automatic Edman degradation method. Miraculin was a single polypeptide with 191 amino acid residues. The calculated molecular weight based on the amino acid sequence and the carbohydrate content (13.9%) was 24,600. Asn-42 and Asn-186 were linked N-glycosidically to carbohydrate chains. High homology was found between the amino acid sequences of miraculin and soybean trypsin inhibitor. PMID:2708331

  10. [EFFECTS OF INGESTING CARBOHYDRATE-PROTEIN SUPPLEMENTS DURING EXERCISE ON ENDURANCE PERFORMANCE: A SYSTEMATIC REVIEW].

    PubMed

    Espino-González, Ever; Muñoz-Daw, María de Jesús; Candia-Lujan, Ramon

    2015-11-01

    Introducción: las bebidas deportivas ayudan a mejorar el rendimiento físico de forma significativa debido a su aporte de carbohidratos, electrolitos y agua. Sin embargo, en las últimas décadas se ha encontrado que ingerir una bebida deportiva con proteína durante el ejercicio mejora el rendimiento físico, produce menores pérdidas de peso corporal inducidas por la deshidratación y ayuda a disminuir el daño muscular postejercicio en comparación con una bebida únicamente con carbohidratos y electrolitos. Objetivo: analizar los principales estudios sobre la efectividad de la ingesta de un suplemento con carbohidratos, proteína y electrolitos durante el ejercicio. Método: se realizó una búsqueda automatizada en Google académico, EBSCO, PubMEd y Scopus, utilizando las palabras clave: Carbohydrate-protein and performance y Added protein and sports drink. Se evaluó la calidad metodológica de los ensayos y se tomó en cuenta que la ingesta del suplemento fuera durante el ejercicio. Resultados: de los veinte artículos que se incluyeron, trece obtuvieron resultados en los que la ingesta de una bebida deportiva con proteína generó mejoras significativas en el rendimiento físico en comparación con una bebida únicamente con carbohidratos y electrolitos, o un placebo. Discusión: aumentar el contenido calórico de las bebidas deportivas al agregar proteína es probablemente una estrategia más efectiva en comparación con disminuir el contenido de carbohidratos para igualar la cantidad de energía. Conclusiones: el consumo de proteína durante el ejercicio posiblemente sirva como una ayuda ergogénica, retardando el tiempo hasta llegar al agotamiento. Sin embargo, hace falta más evidencia que así lo demuestre.

  11. Development of screening methods for detection of carbohydrate-binding proteins by use of soluble glycosylated polyacrylamide-based copolymers.

    PubMed

    Chadli, A; Caron, M; Tichá, M; Joubert, R; Bladier, D; Kocourek, J

    1992-07-01

    Mammalian endogenous carbohydrate-binding proteins (lectins) play fundamental roles in a variety of mechanisms of interactions both at the molecular and cellular levels. We have investigated the binding of one of them (human brain lectin) to soluble acrylamide copolymerized with derivatives of either lactose (O-beta-lactosyloxyallylallylaminoacrylamide copolymer) or D-mannose (D-alpha-mannosyloxyallylallylaminoacrylamide copolymer) in direct enzyme affinoassays, in an attempt to develop simple procedures for detection and estimation of its carbohydrate-binding activity. Biotinylated plant lectins were utilized as reference standards. Affinoassays employed the polymer dotted on nitrocellulose and the polymer coated on microtiter plates as well as detection of bound biotinylated lectin by streptavidin/horseradish peroxidase reagent. Both assays provided reproducible binding, inhibitable by specific sugars. The microtiter plate assay is well suited to sensitive detection of the negative endogenous lectin by competition with biotinylated brain lectin. We conclude that the use of derivatized acrylamide in dotting and microtiter plate assays may prove practical for detection of endogenous lectins and that such polymers may serve as model substances in the study of biological partners of these carbohydrate-binding proteins.

  12. Nutritional physiology of life-history trade-offs: how food protein-carbohydrate content influences life-history traits in the wing-polymorphic cricket Gryllus firmus.

    PubMed

    Clark, Rebecca M; Zera, Anthony J; Behmer, Spencer T

    2015-01-15

    Although life-history trade-offs result from the differential acquisition and allocation of nutritional resources to competing physiological functions, many aspects of this topic remain poorly understood. Wing-polymorphic insects, which possess alternative morphs that trade off allocation to flight capability versus early reproduction, provide a good model system for exploring this topic. In this study, we used the wing-polymorphic cricket Gryllus firmus to test how expression of the flight capability versus reproduction trade-off was modified across a heterogeneous protein-carbohydrate nutritional landscape. Newly molted adult female long- and short-winged crickets were given one of 13 diets with different concentrations and ratios of protein and digestible carbohydrate; for each cricket, we measured consumption patterns, growth and allocation to reproduction (ovary mass) versus flight muscle maintenance (flight muscle mass and somatic lipid stores). Feeding responses in both morphs were influenced more by total macronutrient concentration than by protein-carbohydrate ratio, except at high-macronutrient concentration, where protein-carbohydrate balance was important. Mass gain tended to be greatest on protein-biased diets for both morphs, but was consistently lower across all diets for long-winged females. When long-winged females were fed high-carbohydrate foods, they accumulated greater somatic lipid stores; on high-protein foods, they accumulated greater somatic protein stores. Food protein-carbohydrate content also affected short-winged females (selected for early reproductive onset), which showed dramatic increases in ovary size, including ovarian stores of lipid and protein, on protein-biased foods. This is the first study to show how the concentration and ratio of dietary protein and carbohydrate affects consumption and allocation to key physiological features associated with the reproduction-dispersal life-history trade-off.

  13. Multivariate-parameter optimization of aroma compound release from carbohydrate-oil-protein model emulsions.

    PubMed

    Samavati, Vahid; D-jomeh, Zahra Emam

    2013-11-01

    Optimization for retention and partition coefficient of ethyl acetate in emulsion model systems was investigated using response surface methodology in this paper. The effects of emulsion model ingredients, tragacanth gum (TG) (0.5-1 wt%), whey protein isolate (WPI) (2-4 wt%) and oleic acid (5-10%, v/v) on retention and partition coefficient of ethyl acetate were studied using a five-level three-factor central composite rotatable design (CCRD). Results showed that the regression models generated adequately explained the data variation and significantly represented the actual relationships between the independent and response parameters. The results showed that the highest retention (97.20±0.51%) and lowest partition coefficient (4.51±0.13%) of ethyl acetate were reached at the TG concentration 1 wt%, WPI concentration 4 wt% and oleic acid volume fraction 10% (v/v).

  14. Effect of a carbohydrate-protein multi-ingredient supplement on intermittent sprint performance and muscle damage in recreational athletes.

    PubMed

    Naclerio, Fernando; Larumbe-Zabala, Eneko; Cooper, Robert; Jimenez, Alfonso; Goss-Sampson, Mark

    2014-10-01

    Carbohydrate-protein-based multi-ingredient supplements have been proposed as an effective strategy for limiting the deleterious effects of exercise-induced muscle damage. This study compares the effects of a commercially available carbohydrate-protein supplement enriched with l-glutamine and l-carnitine-l-tartrate to carbohydrate alone or placebo on sprint performance, muscle damage markers, and recovery from intermittent exercise. On 3 occasions, 10 recreationally trained males ingested a multi-ingredient, a carbohydrate supplement, or a placebo before, during, and immediately after a 90-min intermittent repeated sprint test. Fifteen-metre sprint times, creatine kinase, myoglobin, and interleukin-6 were assessed before (pre), immediately after (post), 1 h after (1h), and 24 h after (24h) exercise. Total sprint time measured during the intermittent protocol was not different between conditions. Fifteen-metre sprint time was slower (p < 0.05) at post, 1h and 24h compared with pre without differences between conditions (p > 0.05). Creatine kinase at 24h was lower (p < 0.05) in the multi-ingredient (461.8 ± 271.8 U·L) compared with both carbohydrate and placebo (606 ± 314.5 U·L and 636 ± 344.6 U·L, respectively). Myoglobin increased (p < 0.05) in all 3 conditions at post and 1h compared with pre, showing lower values at 1h (p < 0.05) for the carbohydrate and a trend (p = 0.060) for multi-ingredient compared with the placebo condition (211.4 ± 127.2 ng·mL(-1) and 239.4 ± 103.8 ng·mL(-1) vs. 484.6 ± 200.0 ng·mL(-1), respectively). Interleukin-6 increased at both post and 1h compared with pre (p < 0.05) with no differences between conditions. In conclusion, ingesting a multi-ingredient supplement before, during, and immediately after a 90-min intermittent sprint test resulted in no effects on performance and fatigue while the accumulation of some biomarkers of muscle damage could be attenuated. PMID:25029675

  15. Community-Based Network Study of Protein-Carbohydrate Interactions in Plant Lectins Using Glycan Array Data

    PubMed Central

    Malik, Adeel; Lee, Juyong; Lee, Jooyoung

    2014-01-01

    Lectins play major roles in biological processes such as immune recognition and regulation, inflammatory responses, cytokine signaling, and cell adhesion. Recently, glycan microarrays have shown to play key roles in understanding glycobiology, allowing us to study the relationship between the specificities of glycan binding proteins and their natural ligands at the omics scale. However, one of the drawbacks in utilizing glycan microarray data is the lack of systematic analysis tools to extract information. In this work, we attempt to group various lectins and their interacting carbohydrates by using community-based analysis of a lectin-carbohydrate network. The network consists of 1119 nodes and 16769 edges and we have identified 3 lectins having large degrees of connectivity playing the roles of hubs. The community based network analysis provides an easy way to obtain a general picture of the lectin-glycan interaction and many statistically significant functional groups. PMID:24755681

  16. A new acidic protein in porcine brain.

    PubMed

    Ishioka, N; Isobe, T; Okuyama, T; Numata, Y; Wada, H

    1980-10-21

    An extremely acidic protein has been isolated in a purified form from porcine rain extract, by (NH4)2SO4 fractionation followed by column chromatography on DEAE-Sephadex A-50 and on Sephadex G-75. The purified protein was tentatively named as glutamic acid-rich protein because it was characterized by its remarkably high content of glutamic acid which accounted for 49% of the total amino acid composition. The protein appeared to be a single polypeptide chain with a molecular weight of 56 000-58 000, and had an isoelectric point of 4.6. The N-terminal amino acid sequence was Asp-Glu-Pro-Pro-Ser-Glu-Gly. The immunochemical analysis using rabbit antiserum prepared to the porcine protein has suggested that it is present in the brain of human, cow, cat, dog and goat as well as in various goat organs including liver, kidney, heart, small intestine and spleen.

  17. Effect of timing of protein and carbohydrate intake after resistance exercise on nitrogen balance in trained and untrained young men

    PubMed Central

    2014-01-01

    Background Resistance exercise alters the post-exercise response of anabolic and catabolic hormones. A previous study indicated that the turnover of muscle protein in trained individuals is reduced due to alterations in endocrine factors caused by resistance training, and that muscle protein accumulation varies between trained and untrained individuals due to differences in the timing of protein and carbohydrate intake. We investigated the effect of the timing of protein and carbohydrate intake after resistance exercise on nitrogen balance in trained and untrained young men. Methods Subjects were 10 trained healthy men (mean age, 23 ± 4 years; height, 173.8 ± 3.1 cm; weight, 72.3 ± 4.3 kg) and 10 untrained healthy men (mean age, 23 ± 1 years; height, 171.8 ± 5.0 cm; weight, 64.5 ± 5.0 kg). All subjects performed four sets of 8 to 10 repetitions of a resistance exercise (comprising bench press, shoulder press, triceps pushdown, leg extension, leg press, leg curl, lat pulldown, rowing, and biceps curl) at 80% one-repetition maximum. After each resistance exercise session, subjects were randomly divided into two groups with respect to intake of protein (0.3 g/kg body weight) and carbohydrate (0.8 g/kg body weight) immediately after (P0) or 6 h (P6) after the session. All subjects were on an experimental diet that met their individual total energy requirement. We assessed whole-body protein metabolism by measuring nitrogen balance at P0 and P6 on the last 3 days of exercise training. Results The nitrogen balance was significantly lower in the trained men than in the untrained men at both P0 (P <0.05) and P6 (P <0.01). The nitrogen balance in trained men was significantly higher at P0 than at P6 (P <0.01), whereas that in the untrained men was not significantly different between the two periods. Conclusion The timing of protein and carbohydrate intake after resistance exercise influences nitrogen balance differently in trained and

  18. Detection of AGEs as markers for carbohydrate metabolism and protein denaturation

    PubMed Central

    Nagai, Ryoji; Shirakawa, Jun-ichi; Fujiwara, Yukio; Ohno, Rei-ichi; Moroishi, Narumi; Sakata, Noriyuki; Nagai, Mime

    2014-01-01

    Approximately 100 years have passed since the Maillard reaction was first reported in the field of food chemistry as a condensation reaction between reducing sugars and amino acids. This reaction is thought to progress slowly primarily from glucose with proteins in vivo. An early-stage product, called the ”Amadori product”, is converted into advanced glycation end products. Those accumulate in the body in accordance with age, with such accumulation being enhanced by lifestyle-related diseases that result in the denaturation of proteins. Recent studies have demonstrated that intermediate carbonyls are generated by several pathways, and rapidly generate many glycation products. However, accurate quantification of glycation products in vivo is difficult due to instability and differences in physicochemical properties. In this connection, little is known about the relationship between the structure of glycation products and pathology. Furthermore, the interaction between proteins modified by glycation and receptors for advanced glycation end products is also known to induce the production of several inflammatory cytokines. Therefore, those inhibitors have been developed over the world to prevent lifestyle-related diseases. In this review, we describe the process of protein denaturation induced by glycation and discuss the possibility of using the process as a marker of age-related diseases. PMID:25120273

  19. Effects of sulfhydryl compounds, carbohydrates, organic acids, and sodium sulfite on the formation of lysinoalanine in preserved egg.

    PubMed

    Luo, Xu-Ying; Tu, Yong-Gang; Zhao, Yan; Li, Jian-Ke; Wang, Jun-Jie

    2014-08-01

    To identify inhibitors for lysinoalanine formation in preserved egg, sulfhydryl compounds (glutathione, L-cysteine), carbohydrates (sucrose, D-glucose, maltose), organic acids (L-ascorbic acid, citric acid, DL-malic acid, lactic acid), and sodium sulfite were individually added at different concentrations to a pickling solution to prepare preserved eggs. Lysinoalanine formation as an index of these 10 substances was determined. Results indicate that glutathione, D-glucose, maltose, L-ascorbic acid, citric acid, lactic acid, and sodium sulfite all effectively diminished lysinoalanine formation in preserved egg albumen and yolk. When 40 and 80 mmol/L of sodium sulfite, citric acid, L-ascorbic acid, and D-glucose were individually added into the pickling solution, the inhibition rates of lysinoalanine in the produced preserved egg albumen and yolk were higher. However, the attempt of minimizing lysinoalanine formation was combined with the premise of ensuring preserved eggs quality. Moreover, the addition of 40 and 80 mmol/L of sodium sulfite, 40 and 80 mmol/L of D-glucose, 40 mmol/L of citric acid, and 40 mmol/L of L-ascorbic acid was optimal to produce preserved eggs. The corresponding inhibition rates of lysinoalanine in the albumen were approximately 76.3% to 76.5%, 67.6% to 67.8%, 74.6%, and 74.6%, and the corresponding inhibition rates of lysinoalanine in the yolk were about 68.7% to 69.7%, 50.6% to 51.8%, 70.4%, and 57.8%. It was concluded that sodium sulfite, D-glucose, L-ascorbic, and citric acid at suitable concentrations can be used to control the formation of lysinoalanine during preserved egg processing.

  20. Effects of sulfhydryl compounds, carbohydrates, organic acids, and sodium sulfite on the formation of lysinoalanine in preserved egg.

    PubMed

    Luo, Xu-Ying; Tu, Yong-Gang; Zhao, Yan; Li, Jian-Ke; Wang, Jun-Jie

    2014-08-01

    To identify inhibitors for lysinoalanine formation in preserved egg, sulfhydryl compounds (glutathione, L-cysteine), carbohydrates (sucrose, D-glucose, maltose), organic acids (L-ascorbic acid, citric acid, DL-malic acid, lactic acid), and sodium sulfite were individually added at different concentrations to a pickling solution to prepare preserved eggs. Lysinoalanine formation as an index of these 10 substances was determined. Results indicate that glutathione, D-glucose, maltose, L-ascorbic acid, citric acid, lactic acid, and sodium sulfite all effectively diminished lysinoalanine formation in preserved egg albumen and yolk. When 40 and 80 mmol/L of sodium sulfite, citric acid, L-ascorbic acid, and D-glucose were individually added into the pickling solution, the inhibition rates of lysinoalanine in the produced preserved egg albumen and yolk were higher. However, the attempt of minimizing lysinoalanine formation was combined with the premise of ensuring preserved eggs quality. Moreover, the addition of 40 and 80 mmol/L of sodium sulfite, 40 and 80 mmol/L of D-glucose, 40 mmol/L of citric acid, and 40 mmol/L of L-ascorbic acid was optimal to produce preserved eggs. The corresponding inhibition rates of lysinoalanine in the albumen were approximately 76.3% to 76.5%, 67.6% to 67.8%, 74.6%, and 74.6%, and the corresponding inhibition rates of lysinoalanine in the yolk were about 68.7% to 69.7%, 50.6% to 51.8%, 70.4%, and 57.8%. It was concluded that sodium sulfite, D-glucose, L-ascorbic, and citric acid at suitable concentrations can be used to control the formation of lysinoalanine during preserved egg processing. PMID:25047093

  1. Screening method of carbohydrate-binding proteins in biological sources by capillary affinity electrophoresis and its application to determination of Tulipa gesneriana agglutinin in tulip bulbs.

    PubMed

    Nakajima, Kazuki; Kinoshita, Mitsuhiro; Oda, Yasuo; Masuko, Takashi; Kaku, Hanae; Shibuya, Naoto; Kakehi, Kazuaki

    2004-09-01

    We developed capillary affinity electrophoresis (CAE) to analyze the molecular interaction between carbohydrate chains and proteins in solution state. A mixture of oligosaccharides derived from a glycoprotein was labeled with 8-aminopyrene-1,3,6-trisulfonate (APTS), and used as glycan library without isolation. Interaction of a carbohydrate-binding protein with each oligosaccharide in the mixture could be simultaneously observed, and relative affinities of oligosaccharides toward the protein were accurately determined. In this study, we applied CAE to detect the presence of lectins in some plants (Japanese elderberry bark and tulip bulb). In the crude extract of the elderberry bark, binding activity toward sialo-carbohydrate chains could be easily detected. We also examined the presence of lectins in the crude extract of tulip bulbs and determined the detailed carbohydrate-binding specificity of Tulipa gesneriana agglutinin (TGA), one of the lectins from tulip bulbs. Kinetic studies demonstrated that TGA showed novel carbohydrate-binding specificity and preferentially recognized triantennary oligosaccharides with Gal residues at nonreducing termini and a Fuc residue linked through alpha(1-6) linkage at chitobiose portion of the reducing termini but not tetraantennary carbohydrates. The results described here indicate that CAE will be a valuable method for both screening of lectins in natural sources and determination of their detailed carbohydrate-binding specificities.

  2. Effects of a high-protein, low-carbohydrate v. high-protein, moderate-carbohydrate weight-loss diet on antioxidant status, endothelial markers and plasma indices of the cardiometabolic profile.

    PubMed

    Johnstone, Alexandra M; Lobley, Gerald E; Horgan, Graham W; Bremner, David M; Fyfe, Claire L; Morrice, Philip C; Duthie, Garry G

    2011-07-01

    There are concerns that weight-loss (WL) diets based on very low carbohydrate (LC) intake have a negative impact on antioxidant status and biomarkers of cardiovascular and metabolic health. Obese men (n 16) participated in a randomised, cross-over design diet trial, with food provided daily, at approximately 8.3 MJ/d (approximately 70 % of energy maintenance requirements). They were provided with two high-protein diets (30 % of energy), each for a 4-week period, involving a LC (4 % carbohydrate) and a moderate carbohydrate (MC, 35 % carbohydrate) content. Body weight was measured daily, and weekly blood samples were collected. On average, subjects lost 6.75 and 4.32 kg of weight on the LC and MC diets, respectively (P < 0.001, SED 0.350). Although the LC and MC diets were associated with a small reduction in plasma concentrations of retinol, vitamin E (α-tocopherol) and β-cryptoxanthin (P < 0.005), these were still above the values indicative of deficiency. Interestingly, plasma vitamin C concentrations increased on consumption of the LC diet (P < 0.05). Plasma markers of insulin resistance (P < 0.001), lipaemia and inflammation (P < 0.05, TNF-α and IL-10) improved similarly on both diets. There was no change in other cardiovascular markers with WL. The present data suggest that a LC WL diet does not impair plasma indices of cardiometabolic health, at least within 4 weeks, in otherwise healthy obese subjects. In general, improvements in metabolic health associated with WL were similar between the LC and MC diets. Antioxidant supplements may be warranted if LC WL diets are consumed for a prolonged period.

  3. Effects of Synchronization of Carbohydrate and Protein Supply in Total Mixed Ration with Korean Rice Wine Residue on Ruminal Fermentation, Nitrogen Metabolism and Microbial Protein Synthesis in Holstein Steers

    PubMed Central

    Piao, Min Yu; Kim, Hyun J.; Seo, J. K.; Park, T. S.; Yoon, J. S.; Kim, K. H.; Ha, Jong K.

    2012-01-01

    Three Holstein steers in the growing phase, each with a ruminal cannula, were used to test the hypothesis that the synchronization of the hourly rate of carbohydrate and nitrogen (N) released in the rumen would increase the amount of retained nitrogen for growth and thus improve the efficiency of microbial protein synthesis (EMPS). In Experiment 1, in situ degradability coefficients of carbohydrate and N in feeds including Korean rice wine residue (RWR) were determined. In Experiment 2, three total mixed ration (TMR) diets having different rates of carbohydrate and N release in the rumen were formulated using the in situ degradability of the feeds. All diets were made to contain similar contents of crude protein (CP) and neutral detergent fiber (NDF) but varied in their hourly pattern of nutrient release. The synchrony index of the three TMRs was 0.51 (LS), 0.77 (MS) and 0.95 (HS), respectively. The diets were fed at a restricted level (2% of the animal’s body weight) in a 3×3 Latin-square design. Synchronizing the hourly supply of energy and N in the rumen did not significantly alter the digestibility of dry matter, organic matter, crude protein, NDF or acid detergent fiber (ADF) (p>0.05). The ruminal NH3-N content of the LS group at three hours after feeding was significantly higher (p<0.05) than that of the other groups; however, the mean values of ruminal NH3-N, pH and VFA concentration among the three groups were not significantly different (p>0.05). In addition, the purine derivative (PD) excretion in urine and microbial-N production (MN) among the three groups were not significantly different (p>0.05). In conclusion, synchronizing dietary energy and N supply to the rumen did not have a major effect on nutrient digestion or microbial protein synthesis (MPS) in Holstein steers. PMID:25049518

  4. Differential effects of abscisic acid on desiccation tolerance and carbohydrates in three species of liverworts.

    PubMed

    Pence, Valerie C; Dunford, Susan S; Redella, Steven

    2005-12-01

    Tissues of three species of in vitro grown liverworts, Riccia fluitans, Pallavicinia lyellii, and Marchantia polymorpha, were subjected to rapid drying with and without preculture for 1 week on medium containing 10 microM ABA. ABA preculture initiated total desiccation tolerance in R. fluitans, whereas control tissues were killed after 30 min of drying. Survival was also improved in P. lyellii, whereas ABA did not affect survival of M. polymorpha after rapid drying. ABA treatment did, however, reduce the rate of water loss in M. polymorpha. Total soluble carbohydrates were increased in ABA-treated R. fluitans and P. lyellii, but not in M. polymorpha, although there was no correlation between survival and changes in the percentage of these carbohydrates as reducing sugars. These differences in response to ABA and desiccation likely reflect different adaptations of these three species to conditions in situ.

  5. Balanced intake of protein and carbohydrate maximizes lifetime reproductive success in the mealworm beetle, Tenebrio molitor (Coleoptera: Tenebrionidae).

    PubMed

    Rho, Myung Suk; Lee, Kwang Pum

    2016-01-01

    Recent developments in insect gerontological and nutritional research have suggested that the dietary protein:carbohydrate (P:C) balance is a critical determinant of lifespan and reproduction in many insects. However, most studies investigating this important role of dietary P:C balance have been conducted using dipteran and orthopteran species. In this study, we used the mealworm beetles, Tenebrio molitor L. (Coleoptera: Tenebrionidae), to test the effects of dietary P:C balance on lifespan and reproduction. Regardless of their reproductive status, both male and female beetles had the shortest lifespan at the protein-biased ratio of P:C 5:1. Mean lifespan was the longest at P:C 1:1 for males and at both P:C 1:1 and 1:5 for females. Mating significantly curtailed the lifespan of both males and females, indicating the survival cost of mating. Age-specific egg laying was significantly higher at P:C 1:1 than at the two imbalanced P:C ratios (1:5 or 5:1) at any given age throughout their lives, resulting in the highest lifetime reproductive success at P:C 1:1. When given a choice, beetles actively regulated their intake of protein and carbohydrate to a slightly carbohydrate-biased ratio (P:C 1:1.54-1:1.64 for males and P:C 1:1.3-1:1.36 for females). The self-selected P:C ratio was significantly higher for females than males, reflecting a higher protein requirement for egg production. Collectively, our results add to a growing body of evidence suggesting the key role played by dietary macronutrient balance in shaping lifespan and reproduction in insects. PMID:27405009

  6. Effect of a special carbohydrate-protein bar and tomato juice supplementation on oxidative stress markers and vascular endothelial dynamics in ultra-marathon runners.

    PubMed

    Samaras, Antonios; Tsarouhas, Konstantinos; Paschalidis, Eleftherios; Giamouzis, Grigorios; Triposkiadis, Filippos; Tsitsimpikou, Christina; Becker, Aphrodite Tousia; Goutzourelas, Nikolaos; Kouretas, Demetrios

    2014-07-01

    It is well established that exercise induces excessive production of reactive species leading to oxidative stress, which has been implicated in oxidative damage of macromolecules, immune dysfunction, muscle damage and fatigue. The present study examined the effect of supplementation of ultra-marathon runners for a two-months-period with a special whey protein bar containing carbohydrates and protein in a specific ratio (1:1) (N=16), prepared using as starting material the by-products of cheese manufacturing, and supplementation with commercially available tomato juice (N=15). Thiobarbituric-acid reactive substances and protein carbonyls were significantly decreased in both supplementation groups, while a pronounced increased in reduced glutathione was observed in the protein bar group. Total anti-oxidant activity remained unchanged in both groups. Flow-mediated dilatation, used as an estimate of endothelial function, was increased in both groups, with a significant rise observed only in the tomato juice administration group. In conclusion, supplementation of ultra marathon runners for a two-months-period with a special protein bar and tomato juice significantly improved the oxidative status of the subjects, while tomato juice also improved vascular endothelial function in these athletes.

  7. Protein quality and the protein to carbohydrate ratio within a high fat diet influences energy balance and the gut microbiota in C57BL/6J mice.

    PubMed

    McAllan, Liam; Skuse, Peter; Cotter, Paul D; O'Connor, Paula; Cryan, John F; Ross, R Paul; Fitzgerald, Gerald; Roche, Helen M; Nilaweera, Kanishka N

    2014-01-01

    Macronutrient quality and composition are important determinants of energy balance and the gut microbiota. Here, we investigated how changes to protein quality (casein versus whey protein isolate; WPI) and the protein to carbohydrate (P/C) ratio within a high fat diet (HFD) impacts on these parameters. Mice were fed a low fat diet (10% kJ) or a high fat diet (HFD; 45% kJ) for 21 weeks with either casein (20% kJ, HFD) or WPI at 20%, 30% or 40% kJ. In comparison to casein, WPI at a similar energy content normalised energy intake, increased lean mass and caused a trend towards a reduction in fat mass (P = 0.08), but the protein challenge did not alter oxygen consumption or locomotor activity. WPI reduced HFD-induced plasma leptin and liver triacylglycerol, and partially attenuated the reduction in adipose FASN mRNA in HFD-fed mice. High throughput sequence-based analysis of faecal microbial populations revealed microbiota in the HFD-20% WPI group clustering closely with HFD controls, although WPI specifically increased Lactobacillaceae/Lactobacillus and decreased Clostridiaceae/Clostridium in HFD-fed mice. There was no effect of increasing the P/C ratio on energy intake, but the highest ratio reduced HFD-induced weight gain, fat mass and plasma triacylglycerol, non-esterified fatty acids, glucose and leptin levels, while it increased lean mass and oxygen consumption. Similar effects were observed on adipose mRNA expression, where the highest ratio reduced HFD-associated expression of UCP-2, TNFα and CD68 and increased the diet-associated expression of β3-AR, LPL, IR, IRS-1 and GLUT4. The P/C ratio also impacted on gut microbiota, with populations in the 30/40% WPI groups clustering together and away from the 20% WPI group. Taken together, our data show that increasing the P/C ratio has a dramatic effect on energy balance and the composition of gut microbiota, which is distinct from that caused by changes to protein quality.

  8. Screening Carbohydrate Libraries for Protein Interactions Using the Direct ESI-MS Assay. Applications to Libraries of Unknown Concentration

    NASA Astrophysics Data System (ADS)

    Kitova, Elena N.; El-Hawiet, Amr; Klassen, John S.

    2014-08-01

    A semiquantitative electrospray ionization mass spectrometry (ESI-MS) binding assay suitable for analyzing mixtures of oligosaccharides, at unknown concentrations, for interactions with target proteins is described. The assay relies on the differences in the ratio of the relative abundances of the ligand-bound and free protein ions measured by ESI-MS at two or more initial protein concentrations to distinguish low affinity (≤103 M-1) ligands from moderate and high affinity (>105 M-1) ligands present in the library and to rank their affinities. Control experiments were performed on solutions of a single chain antibody and a mixture of synthetic oligosaccharides, with known affinities, in the absence and presence of a 40-component carbohydrate library to demonstrate the implementation and reliability of the assay. The application of the assay for screening natural libraries of carbohydrates against proteins is also demonstrated using mixtures of human milk oligosaccharides, isolated from breast milk, and fragments of a bacterial toxin and human galectin 3.

  9. Reduced steric hindrance and optimized spatial arrangement of carbohydrate ligands in imprinted monolayers for enhanced protein binding.

    PubMed

    Zheng, Haifu; Du, Xuezhong

    2013-02-01

    Imprinted monolayers provide several advantages over bulk imprinting methods. This is especially important for large templates such as proteins. Concanavalin A (Con A)-imprinted binary monolayers consisting of glycolipids with oligo(ethylene glycol) (OEG) spacers and zwitterionic phospholipids (DPPC) were constructed and investigated. The shorter phosphorylcholine (PC) headgroups with an almost flat-on orientation in the binary monolayers gave rise to reduced steric hindrance favorable to the accommodation of Con A with greater ease and facilitated the access of the OEG-linked mannose moieties for enhanced protein binding. Further enhanced binding resulted from optimized spatial rearrangement of the glycolipids at the air-water interface directed by Con A in the subphase to create bivalent binding sites and to minimize steric crowding of neighboring mannose ligands. The combination of the exposed carbohydrate ligands from biologically inert surfaces and the optimized ligand arrangement is the most reasonable solution to enhancement of protein affinity. The bivalent carbohydrate binding sites protruding from the imprinted monolayers were created to be complementary to the Con A binding pockets. This strategy generates tailor-made surfaces with enhanced protein binding and opens the possibility of controlled assembly of intellectual biomaterials and preparation of biosensors.

  10. The role of the glucose-sensing transcription factor carbohydrate-responsive element-binding protein pathway in termite queen fertility.

    PubMed

    Sillam-Dussès, David; Hanus, Robert; Poulsen, Michael; Roy, Virginie; Favier, Maryline; Vasseur-Cognet, Mireille

    2016-05-01

    Termites are among the few animals that themselves can digest the most abundant organic polymer, cellulose, into glucose. In mice and Drosophila, glucose can activate genes via the transcription factor carbohydrate-responsive element-binding protein (ChREBP) to induce glucose utilization and de novo lipogenesis. Here, we identify a termite orthologue of ChREBP and its downstream lipogenic targets, including acetyl-CoA carboxylase and fatty acid synthase. We show that all of these genes, including ChREBP, are upregulated in mature queens compared with kings, sterile workers and soldiers in eight different termite species. ChREBP is expressed in several tissues, including ovaries and fat bodies, and increases in expression in totipotent workers during their differentiation into neotenic mature queens. We further show that ChREBP is regulated by a carbohydrate diet in termite queens. Suppression of the lipogenic pathway by a pharmacological agent in queens elicits the same behavioural alterations in sterile workers as observed in queenless colonies, supporting that the ChREBP pathway partakes in the biosynthesis of semiochemicals that convey the signal of the presence of a fertile queen. Our results highlight ChREBP as a likely key factor for the regulation and signalling of queen fertility. PMID:27249798

  11. The role of the glucose-sensing transcription factor carbohydrate-responsive element-binding protein pathway in termite queen fertility

    PubMed Central

    Sillam-Dussès, David; Hanus, Robert; Poulsen, Michael; Roy, Virginie; Favier, Maryline

    2016-01-01

    Termites are among the few animals that themselves can digest the most abundant organic polymer, cellulose, into glucose. In mice and Drosophila, glucose can activate genes via the transcription factor carbohydrate-responsive element-binding protein (ChREBP) to induce glucose utilization and de novo lipogenesis. Here, we identify a termite orthologue of ChREBP and its downstream lipogenic targets, including acetyl-CoA carboxylase and fatty acid synthase. We show that all of these genes, including ChREBP, are upregulated in mature queens compared with kings, sterile workers and soldiers in eight different termite species. ChREBP is expressed in several tissues, including ovaries and fat bodies, and increases in expression in totipotent workers during their differentiation into neotenic mature queens. We further show that ChREBP is regulated by a carbohydrate diet in termite queens. Suppression of the lipogenic pathway by a pharmacological agent in queens elicits the same behavioural alterations in sterile workers as observed in queenless colonies, supporting that the ChREBP pathway partakes in the biosynthesis of semiochemicals that convey the signal of the presence of a fertile queen. Our results highlight ChREBP as a likely key factor for the regulation and signalling of queen fertility. PMID:27249798

  12. Proteins and Carbohydrates from Red Seaweeds: Evidence for Beneficial Effects on Gut Function and Microbiota.

    PubMed

    Cian, Raúl E; Drago, Silvina R; de Medina, Fermín Sánchez; Martínez-Augustin, Olga

    2015-08-20

    Based on their composition, marine algae, and namely red seaweeds, are good potential functional foods. Intestinal mucosal barrier function refers to the capacity of the intestine to provide adequate containment of luminal microorganisms and molecules. Here, we will first outline the component of seaweeds and will summarize the effects of these on the regulation of mucosal barrier function. Special attention will be paid to unique components of red seaweeds: proteins and derived peptides (e.g., phycobiliproteins, glycoproteins that contain "cellulose binding domains", phycolectins and the related mycosporine-like amino acids) together with polysaccharides (e.g., floridean starch and sulfated galactans, such as carrageenans, agarans and "dl-hybrid") and minerals. These compounds have been shown to exert prebiotic effects, to regulate intestinal epithelial cell, macrophage and lymphocyte proliferation and differentiation and to modulate the immune response. Molecular mechanisms of action of peptides and polysaccharides are starting to be elucidated, and evidence indicating the involvement of epidermal growth factor receptor (EGFR), insulin-like growth factor receptor (IGFR), Toll-like receptors (TLR) and signal transduction pathways mediated by protein kinase B (PKB or AKT), nuclear factor-κB (NF-κB) and mitogen activated protein kinases (MAPK) will also be summarized. The need for further research is clear, but in vivo experiments point to an overall antiinflammatory effect of these algae, indicating that they can reinforce membrane barrier function.

  13. Proteins and Carbohydrates from Red Seaweeds: Evidence for Beneficial Effects on Gut Function and Microbiota.

    PubMed

    Cian, Raúl E; Drago, Silvina R; de Medina, Fermín Sánchez; Martínez-Augustin, Olga

    2015-08-01

    Based on their composition, marine algae, and namely red seaweeds, are good potential functional foods. Intestinal mucosal barrier function refers to the capacity of the intestine to provide adequate containment of luminal microorganisms and molecules. Here, we will first outline the component of seaweeds and will summarize the effects of these on the regulation of mucosal barrier function. Special attention will be paid to unique components of red seaweeds: proteins and derived peptides (e.g., phycobiliproteins, glycoproteins that contain "cellulose binding domains", phycolectins and the related mycosporine-like amino acids) together with polysaccharides (e.g., floridean starch and sulfated galactans, such as carrageenans, agarans and "dl-hybrid") and minerals. These compounds have been shown to exert prebiotic effects, to regulate intestinal epithelial cell, macrophage and lymphocyte proliferation and differentiation and to modulate the immune response. Molecular mechanisms of action of peptides and polysaccharides are starting to be elucidated, and evidence indicating the involvement of epidermal growth factor receptor (EGFR), insulin-like growth factor receptor (IGFR), Toll-like receptors (TLR) and signal transduction pathways mediated by protein kinase B (PKB or AKT), nuclear factor-κB (NF-κB) and mitogen activated protein kinases (MAPK) will also be summarized. The need for further research is clear, but in vivo experiments point to an overall antiinflammatory effect of these algae, indicating that they can reinforce membrane barrier function. PMID:26308006

  14. Proteins and Carbohydrates from Red Seaweeds: Evidence for Beneficial Effects on Gut Function and Microbiota

    PubMed Central

    Cian, Raúl E.; Drago, Silvina R.; Sánchez de Medina, Fermín; Martínez-Augustin, Olga

    2015-01-01

    Based on their composition, marine algae, and namely red seaweeds, are good potential functional foods. Intestinal mucosal barrier function refers to the capacity of the intestine to provide adequate containment of luminal microorganisms and molecules. Here, we will first outline the component of seaweeds and will summarize the effects of these on the regulation of mucosal barrier function. Special attention will be paid to unique components of red seaweeds: proteins and derived peptides (e.g., phycobiliproteins, glycoproteins that contain “cellulose binding domains”, phycolectins and the related mycosporine-like amino acids) together with polysaccharides (e.g., floridean starch and sulfated galactans, such as carrageenans, agarans and “dl-hybrid”) and minerals. These compounds have been shown to exert prebiotic effects, to regulate intestinal epithelial cell, macrophage and lymphocyte proliferation and differentiation and to modulate the immune response. Molecular mechanisms of action of peptides and polysaccharides are starting to be elucidated, and evidence indicating the involvement of epidermal growth factor receptor (EGFR), insulin-like growth factor receptor (IGFR), Toll-like receptors (TLR) and signal transduction pathways mediated by protein kinase B (PKB or AKT), nuclear factor-κB (NF-κB) and mitogen activated protein kinases (MAPK) will also be summarized. The need for further research is clear, but in vivo experiments point to an overall antiinflammatory effect of these algae, indicating that they can reinforce membrane barrier function. PMID:26308006

  15. Effects of protein level, methionine supplementation and carbohydrate type of the diet on liver lipid and plasma free threonine contents in the lactating rat.

    PubMed

    Leclerc, J; Chanussot, B; Miller, M L; Poisson, J P; Belleville, J

    1989-01-01

    Eight groups of 13-15 female rats were fed purified diets after littering. Four groups received a low protein (8% casein) diet (groups 8) and the others, a normal protein (20% casein) diet (groups 20). Carbohydrates were supplied either as starch (groups S) or as starch plus 40% fructose (groups F). Half the animals received a 0.4% methionine supplementation (groups M). Four or five dams per group were sacrificed on days 2, 7 and 14 after littering. The diet intake was increased by methionine supplementation, substitution of starch for fructose and increased protein content, mainly during the second week of lactation. This influenced weight variation of the dams and litter growth. On all days, the plasma levels of cholesterol esters, triglycerides and phospholipids were positively correlated with the dietary protein level. On days 7 and 14, the liver neutral lipid content was increased in rats fed the low protein diets supplemented with methionine (groups 8SM and 8FM) and the normal protein diets containing 40% fructose (groups 20F and 20FM). The plasma free threonine content was positively correlated with the protein level in the diet. On day 14, rats fed a low protein diet had a threonine deficiency, except those in groups 8S and 8F. The plasma free threonine content of these rats was not reduced, possibly due to an impaired utilization of this amino acid. The liver lipidosis observed during lactation, in contrast to that observed during growth with a low protein diet, was not due to a threonine deficiency.

  16. Trends in dietary energy, fat, carbohydrate and protein intake in Chinese children and adolescents from 1991 to 2009.

    PubMed

    Cui, Zhaohui; Dibley, Michael J

    2012-10-01

    Few studies have examined nutrition transition in children in China. Our aim, in the present study, was to examine temporal trends in dietary energy, fat, carbohydrate and protein intake in Chinese children aged 7-17 years. The analysis used individual level, consecutive 3 d dietary recall data from seven rounds of the China Health and Nutrition Surveys in 1991 (n 2714), 1993 (n 2542), 1997 (n 2516), 2000 (n 2142), 2004 (n 1341), 2006 (n 1072) and 2009 (n 996). Mixed-effect models were constructed to obtain adjusted means and to examine trends after adjusting for intra-class correlation within clusters and for covariates including age, sex, urban/rural residence and income. From 1991 to 2009, daily energy intake steadily declined from 9511·0 to 7658·2 kJ (P<0·0001). There was a steady decline in daily carbohydrate intake from 382·5 to 254·1 g (P<0·0001), and in the proportion of energy from carbohydrate from 66·7 to 56·8 % (P<0·0001). In contrast, daily fat intake steadily increased from 54·8 to 66·0 g (P<0·0001), as did the proportion of energy from fat from 21·5 to 30·0 % (P<0·0001). The proportion of children who consumed a diet with more than 30 % of energy from fat increased from 20·1 to 49·4 % (P<0·0001). The proportion of energy from protein increased from 11·8 to 13·1 % (P<0·0001), although daily protein intake dropped from 66·2 to 58·0 g (P<0·0001). Our data suggest that Chinese children have been undergoing a rapid nutrition transition to a high-fat diet.

  17. Carbohydrates in Supramolecular Chemistry.

    PubMed

    Delbianco, Martina; Bharate, Priya; Varela-Aramburu, Silvia; Seeberger, Peter H

    2016-02-24

    Carbohydrates are involved in a variety of biological processes. The ability of sugars to form a large number of hydrogen bonds has made them important components for supramolecular chemistry. We discuss recent advances in the use of carbohydrates in supramolecular chemistry and reveal that carbohydrates are useful building blocks for the stabilization of complex architectures. Systems are presented according to the scaffold that supports the glyco-conjugate: organic macrocycles, dendrimers, nanomaterials, and polymers are considered. Glyco-conjugates can form host-guest complexes, and can self-assemble by using carbohydrate-carbohydrate interactions and other weak interactions such as π-π interactions. Finally, complex supramolecular architectures based on carbohydrate-protein interactions are discussed.

  18. A functional glycoprotein competitive recognition and signal amplification strategy for carbohydrate-protein interaction profiling and cell surface carbohydrate expression evaluation

    NASA Astrophysics Data System (ADS)

    Wang, Yangzhong; Chen, Zhuhai; Liu, Yang; Li, Jinghong

    2013-07-01

    A simple and sensitive carbohydrate biosensor has been suggested as a potential tool for accurate analysis of cell surface carbohydrate expression as well as carbohydrate-based therapeutics for a variety of diseases and infections. In this work, a sensitive biosensor for carbohydrate-lectin profiling and in situ cell surface carbohydrate expression was designed by taking advantage of a functional glycoprotein of glucose oxidase acting as both a multivalent recognition unit and a signal amplification probe. Combining the gold nanoparticle catalyzed luminol electrogenerated chemiluminescence and nanocarrier for active biomolecules, the number of cell surface carbohydrate groups could be conveniently read out. The apparent dissociation constant between GOx@Au probes and Con A was detected to be 1.64 nM and was approximately 5 orders of magnitude smaller than that of mannose and Con A, which would arise from the multivalent effect between the probe and Con A. Both glycoproteins and gold nanoparticles contribute to the high affinity between carbohydrates and lectin. The as-proposed biosensor exhibits excellent analytical performance towards the cytosensing of K562 cells with a detection limit of 18 cells, and the mannose moieties on a single K562 cell were determined to be 1.8 × 1010. The biosensor can also act as a useful tool for antibacterial drug screening and mechanism investigation. This strategy integrates the excellent biocompatibility and multivalent recognition of glycoproteins as well as the significant enzymatic catalysis and gold nanoparticle signal amplification, and avoids the cell pretreatment and labelling process. This would contribute to the glycomic analysis and the understanding of complex native glycan-related biological processes.A simple and sensitive carbohydrate biosensor has been suggested as a potential tool for accurate analysis of cell surface carbohydrate expression as well as carbohydrate-based therapeutics for a variety of diseases and

  19. A functional glycoprotein competitive recognition and signal amplification strategy for carbohydrate-protein interaction profiling and cell surface carbohydrate expression evaluation.

    PubMed

    Wang, Yangzhong; Chen, Zhuhai; Liu, Yang; Li, Jinghong

    2013-08-21

    A simple and sensitive carbohydrate biosensor has been suggested as a potential tool for accurate analysis of cell surface carbohydrate expression as well as carbohydrate-based therapeutics for a variety of diseases and infections. In this work, a sensitive biosensor for carbohydrate-lectin profiling and in situ cell surface carbohydrate expression was designed by taking advantage of a functional glycoprotein of glucose oxidase acting as both a multivalent recognition unit and a signal amplification probe. Combining the gold nanoparticle catalyzed luminol electrogenerated chemiluminescence and nanocarrier for active biomolecules, the number of cell surface carbohydrate groups could be conveniently read out. The apparent dissociation constant between GOx@Au probes and Con A was detected to be 1.64 nM and was approximately 5 orders of magnitude smaller than that of mannose and Con A, which would arise from the multivalent effect between the probe and Con A. Both glycoproteins and gold nanoparticles contribute to the high affinity between carbohydrates and lectin. The as-proposed biosensor exhibits excellent analytical performance towards the cytosensing of K562 cells with a detection limit of 18 cells, and the mannose moieties on a single K562 cell were determined to be 1.8 × 10(10). The biosensor can also act as a useful tool for antibacterial drug screening and mechanism investigation. This strategy integrates the excellent biocompatibility and multivalent recognition of glycoproteins as well as the significant enzymatic catalysis and gold nanoparticle signal amplification, and avoids the cell pretreatment and labelling process. This would contribute to the glycomic analysis and the understanding of complex native glycan-related biological processes.

  20. Carbohydrate Dehydration Demonstrations.

    ERIC Educational Resources Information Center

    Dolson, David A.; And Others

    1995-01-01

    Discusses the impact of various factors on the "charring reaction" of a carbohydrate with concentrated sulfuric acid including the type of sugar, the degree of fineness of the sugar crystals, and the amount of water added. (JRH)

  1. Production of hybrid diesel fuel precursors from carbohydrates and petrochemicals using formic acid as a reactive solvent.

    PubMed

    Zhou, Xiaoyuan; Rauchfuss, Thomas B

    2013-02-01

    We report the one-pot alkylation of mesitylene with carbohydrate-derived 5-(hydroxymethyl)furfural (HMF) as a step toward diesel-range liquids. Using FeCl(3) as a catalyst, HMF is shown to alkylate toluene, xylene, and mesitylene in high yields in CH(2)Cl(2) and MeNO(2) solvents. Efforts to extend this reaction to greener or safer solvents showed that most ether-based solvents are unsatisfactory. Acid catalysts (e.g, p-TsOH) also proved to be ineffective. Using formic acid as a reactive solvent, mesitylene could be alkylated to give mesitylmethylfurfural (MMF) starting from fructose with yields up to approximately 70 %. The reaction of fructose with formic acid in the absence of mesitylene gave rise to low yields of the formate ester of HMF, which indicates the stabilizing effect of replacing the hydroxyl substituent with mesityl. The arene also serves as a second phase into which the product is extracted. Even by using formic acid, the mesitylation of less expensive precursors such as glucose and cellulose proceeded only in modest yields (ca. 20 %). These simpler substrates were found to undergo mesitylation by using hydrogen chloride/formic acid via the intermediate chloromethylfurfural. PMID:23281330

  2. Taste modulating N-(1-methyl-4-oxoimidazolidin-2-ylidene) α-amino acids formed from creatinine and reducing carbohydrates.

    PubMed

    Kunert, Christof; Walker, Alesia; Hofmann, Thomas

    2011-08-10

    Recent investigations led to the discovery of N-(1-methyl-4-oxoimidazolidin-2-ylidene)aminopropionic acid as a taste modulator enhancing the typical thick-sour mouthdryness and mouthfulness imparted by stewed beef juice. In the present study, systematic model reactions were targeted toward the generation of a series of N-(1-methyl-4-oxoimidazolidin-2-ylidene)-α-amino acids by Maillard-type reactions between creatinine and ribose, glucose, methylglyoxal, or glyoxal, respectively. By application of a comparative taste dilution analysis on fractions isolated from thermally treated creatinine/carbohydrate mixtures by means of hydrophilic liquid interaction chromatography (HILIC), a total of nine N-(1-methyl-4-oxoimidazolidin-2-ylidene)-α-amino acids were identified by means of LC-MS, LC-TOF-MS, and 1D/2D NMR experiments. Six of the nine creatinine glycation products were previously not reported in the literature. Whereas creatinine exhibited a bitter taste, none of the N-(1-methyl-4-oxoimidazolidin-2-ylidene)-α-amino acids imparted any intrinsic taste activity up to levels of 10 mmol/L (in water). Depending strongly on their chemical structure, these N-(1-methyl-4-oxoimidazolidin-2-ylidene)-α-amino acids induced a thick-sour, mouthdrying orosensation and mouthfulness enhancement when evaluated in model broth with recognition thresholds ranging from 31 to >1000 μmol/L.

  3. Production of hybrid diesel fuel precursors from carbohydrates and petrochemicals using formic acid as a reactive solvent.

    PubMed

    Zhou, Xiaoyuan; Rauchfuss, Thomas B

    2013-02-01

    We report the one-pot alkylation of mesitylene with carbohydrate-derived 5-(hydroxymethyl)furfural (HMF) as a step toward diesel-range liquids. Using FeCl(3) as a catalyst, HMF is shown to alkylate toluene, xylene, and mesitylene in high yields in CH(2)Cl(2) and MeNO(2) solvents. Efforts to extend this reaction to greener or safer solvents showed that most ether-based solvents are unsatisfactory. Acid catalysts (e.g, p-TsOH) also proved to be ineffective. Using formic acid as a reactive solvent, mesitylene could be alkylated to give mesitylmethylfurfural (MMF) starting from fructose with yields up to approximately 70 %. The reaction of fructose with formic acid in the absence of mesitylene gave rise to low yields of the formate ester of HMF, which indicates the stabilizing effect of replacing the hydroxyl substituent with mesityl. The arene also serves as a second phase into which the product is extracted. Even by using formic acid, the mesitylation of less expensive precursors such as glucose and cellulose proceeded only in modest yields (ca. 20 %). These simpler substrates were found to undergo mesitylation by using hydrogen chloride/formic acid via the intermediate chloromethylfurfural.

  4. Production and applications of carbohydrate-derived sugar acids as generic biobased chemicals.

    PubMed

    Mehtiö, Tuomas; Toivari, Mervi; Wiebe, Marilyn G; Harlin, Ali; Penttilä, Merja; Koivula, Anu

    2016-10-01

    This review considers the chemical and biotechnological synthesis of acids that are obtained by direct oxidation of mono- or oligosaccharide, referred to as sugar acids. It focuses on sugar acids which can be readily derived from plant biomass sources and their current and future applications. The three main classes of sugar acids are aldonic, aldaric and uronic acids. Interest in organic acids derived from sugars has recently increased, as part of the interest to develop biorefineries which produce not only biofuels, but also chemicals to replace those currently derived from petroleum. More than half of the most desirable biologically produced platform chemicals are organic acids. Currently, the only sugar acid with high commercial production is d-gluconic acid. However, other sugar acids such as d-glucaric and meso-galactaric acids are being produced at a lower scale. The sugar acids have application as sequestering agents and binders, corrosion inhibitors, biodegradable chelators for pharmaceuticals and pH regulators. There is also considerable interest in the use of these molecules in the production of synthetic polymers, including polyamides, polyesters and hydrogels. Further development of these sugar acids will lead to higher volume production of the appropriate sugar acids and will help support the next generation of biorefineries.

  5. BIOPOLYMERS FROM POLYLACTIC ACID AND MILK PROTEINS

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Polylactic acid (PLA) is a commercially available biodegradable polymer derived from lactic acid and is used in many nonfood products as an alternative to petrochemical-derived polymers. However, its physical properties limit its use in many applications. Using dairy proteins to substitute for por...

  6. Ferulic Acid Alleviates Changes in a Rat Model of Metabolic Syndrome Induced by High-Carbohydrate, High-Fat Diet.

    PubMed

    Senaphan, Ketmanee; Kukongviriyapan, Upa; Sangartit, Weerapon; Pakdeechote, Poungrat; Pannangpetch, Patchareewan; Prachaney, Parichat; Greenwald, Stephen E; Kukongviriyapan, Veerapol

    2015-08-01

    Metabolic syndrome is a cluster of metabolic abnormalities characterized by obesity, insulin resistance, hypertension and dyslipidemia. Ferulic acid (FA) is the major phenolic compound found in rice oil and various fruits and vegetables. In this study, we examined the beneficial effects of FA in minimizing insulin resistance, vascular dysfunction and remodeling in a rat model of high-carbohydrate, high-fat diet-induced metabolic changes, which is regarded as an analogue of metabolic syndrome (MS) in man. Male Sprague-Dawley rats were fed a high carbohydrate, high fat (HCHF) diet and 15% fructose in drinking water for 16 weeks, where control rats were fed with standard chow diet and tap water. FA (30 or 60 mg/kg) was orally administered to the HCHF and control rats during the last six weeks of the study. We observed that FA significantly improved insulin sensitivity and lipid profiles, and reduced elevated blood pressure, compared to untreated controls (p < 0.05). Moreover, FA also improved vascular function and prevented vascular remodeling of mesenteric arteries. The effects of FA in HCHF-induced MS may be realized through suppression of oxidative stress by down-regulation of p47phox, increased nitric oxide (NO) bioavailability with up-regulation of endothelial nitric oxide synthase (eNOS) and suppression of tumor necrosis factor-α (TNF-α). Our results suggest that supplementation of FA may have health benefits by minimizing the cardiovascular complications of MS and alleviating its symptoms. PMID:26247970

  7. Ferulic Acid Alleviates Changes in a Rat Model of Metabolic Syndrome Induced by High-Carbohydrate, High-Fat Diet.

    PubMed

    Senaphan, Ketmanee; Kukongviriyapan, Upa; Sangartit, Weerapon; Pakdeechote, Poungrat; Pannangpetch, Patchareewan; Prachaney, Parichat; Greenwald, Stephen E; Kukongviriyapan, Veerapol

    2015-08-04

    Metabolic syndrome is a cluster of metabolic abnormalities characterized by obesity, insulin resistance, hypertension and dyslipidemia. Ferulic acid (FA) is the major phenolic compound found in rice oil and various fruits and vegetables. In this study, we examined the beneficial effects of FA in minimizing insulin resistance, vascular dysfunction and remodeling in a rat model of high-carbohydrate, high-fat diet-induced metabolic changes, which is regarded as an analogue of metabolic syndrome (MS) in man. Male Sprague-Dawley rats were fed a high carbohydrate, high fat (HCHF) diet and 15% fructose in drinking water for 16 weeks, where control rats were fed with standard chow diet and tap water. FA (30 or 60 mg/kg) was orally administered to the HCHF and control rats during the last six weeks of the study. We observed that FA significantly improved insulin sensitivity and lipid profiles, and reduced elevated blood pressure, compared to untreated controls (p < 0.05). Moreover, FA also improved vascular function and prevented vascular remodeling of mesenteric arteries. The effects of FA in HCHF-induced MS may be realized through suppression of oxidative stress by down-regulation of p47phox, increased nitric oxide (NO) bioavailability with up-regulation of endothelial nitric oxide synthase (eNOS) and suppression of tumor necrosis factor-α (TNF-α). Our results suggest that supplementation of FA may have health benefits by minimizing the cardiovascular complications of MS and alleviating its symptoms.

  8. Ferulic Acid Alleviates Changes in a Rat Model of Metabolic Syndrome Induced by High-Carbohydrate, High-Fat Diet

    PubMed Central

    Senaphan, Ketmanee; Kukongviriyapan, Upa; Sangartit, Weerapon; Pakdeechote, Poungrat; Pannangpetch, Patchareewan; Prachaney, Parichat; Greenwald, Stephen E.; Kukongviriyapan, Veerapol

    2015-01-01

    Metabolic syndrome is a cluster of metabolic abnormalities characterized by obesity, insulin resistance, hypertension and dyslipidemia. Ferulic acid (FA) is the major phenolic compound found in rice oil and various fruits and vegetables. In this study, we examined the beneficial effects of FA in minimizing insulin resistance, vascular dysfunction and remodeling in a rat model of high-carbohydrate, high-fat diet-induced metabolic changes, which is regarded as an analogue of metabolic syndrome (MS) in man. Male Sprague-Dawley rats were fed a high carbohydrate, high fat (HCHF) diet and 15% fructose in drinking water for 16 weeks, where control rats were fed with standard chow diet and tap water. FA (30 or 60 mg/kg) was orally administered to the HCHF and control rats during the last six weeks of the study. We observed that FA significantly improved insulin sensitivity and lipid profiles, and reduced elevated blood pressure, compared to untreated controls (p < 0.05). Moreover, FA also improved vascular function and prevented vascular remodeling of mesenteric arteries. The effects of FA in HCHF-induced MS may be realized through suppression of oxidative stress by down-regulation of p47phox, increased nitric oxide (NO) bioavailability with up-regulation of endothelial nitric oxide synthase (eNOS) and suppression of tumor necrosis factor-α (TNF-α). Our results suggest that supplementation of FA may have health benefits by minimizing the cardiovascular complications of MS and alleviating its symptoms. PMID:26247970

  9. Towards a synthesis of frameworks in nutritional ecology: interacting effects of protein, carbohydrate and phosphorus on field cricket fitness.

    PubMed

    Harrison, Sarah J; Raubenheimer, David; Simpson, Stephen J; Godin, Jean-Guy J; Bertram, Susan M

    2014-10-01

    Phosphorus has been identified as an important determinant of nutrition-related biological variation. The macronutrients protein (P) and carbohydrates (C), both alone and interactively, are known to affect animal performance. No study, however, has investigated the importance of phosphorus relative to dietary protein or carbohydrates, or the interactive effects of phosphorus with these macronutrients, on fitness-related traits in animals. We used a nutritional geometry framework to address this question in adult field crickets (Gryllus veletis). Our results showed that lifespan, weight gain, acoustic mate signalling and egg production were maximized on diets with different P : C ratios, that phosphorus did not positively affect any of these fitness traits, and that males and females had different optimal macronutrient intake ratios for reproductive performance. When given a choice, crickets selected diets that maximized both lifespan and reproductive performance by preferentially eating diets with low P : C ratios, and females selected diets with a higher P : C ratio than males. Conversely, phosphorus intake was not regulated. Overall, our findings highlight the importance of disentangling the influences of different nutrients, and of quantifying both their individual and interactive effects, on animal fitness traits, so as to gain a more integrative understanding of their nutritional ecology.

  10. Towards a synthesis of frameworks in nutritional ecology: interacting effects of protein, carbohydrate and phosphorus on field cricket fitness

    PubMed Central

    Harrison, Sarah J.; Raubenheimer, David; Simpson, Stephen J.; Godin, Jean-Guy J.; Bertram, Susan M.

    2014-01-01

    Phosphorus has been identified as an important determinant of nutrition-related biological variation. The macronutrients protein (P) and carbohydrates (C), both alone and interactively, are known to affect animal performance. No study, however, has investigated the importance of phosphorus relative to dietary protein or carbohydrates, or the interactive effects of phosphorus with these macronutrients, on fitness-related traits in animals. We used a nutritional geometry framework to address this question in adult field crickets (Gryllus veletis). Our results showed that lifespan, weight gain, acoustic mate signalling and egg production were maximized on diets with different P : C ratios, that phosphorus did not positively affect any of these fitness traits, and that males and females had different optimal macronutrient intake ratios for reproductive performance. When given a choice, crickets selected diets that maximized both lifespan and reproductive performance by preferentially eating diets with low P : C ratios, and females selected diets with a higher P : C ratio than males. Conversely, phosphorus intake was not regulated. Overall, our findings highlight the importance of disentangling the influences of different nutrients, and of quantifying both their individual and interactive effects, on animal fitness traits, so as to gain a more integrative understanding of their nutritional ecology. PMID:25143029

  11. Anti-inflammatory effects of a special carbohydrate-whey protein cake after exhaustive cycling in humans.

    PubMed

    Kerasioti, Efthalia; Stagos, Dimitrios; Jamurtas, Athanasios; Kiskini, Alexandra; Koutedakis, Yiannis; Goutzourelas, Nikos; Pournaras, Spyros; Tsatsakis, Aristidis M; Kouretas, Dimitrios

    2013-11-01

    Intense exercise induces increased levels of pro-inflammatory and anti-inflammatory cytokines. Thus, the purpose of this study was to examine the effects of a special cake (consisting of carbohydrate to whey protein 3.5:1) vs. an isocaloric carbohydrate cake on inflammatory markers after exhaustive cycling in humans. Nine subjects received either the experimental or placebo cake in a counterbalanced fashion using a crossover, double-blind, repeated-measures design. They performed one trial involving a 2h exercise on a cycle ergometer at 60-65% VO2max followed by a 4h recovery and then a second trial involving an 1h exercise at 60-65% VO2max which was increased at 95% VO2max. Blood samples were collected pre-exercise, 30 min and 4h post-exercise, post-time Trial and 48 h post-time Trial. Cakes were consumed immediately post-exercise and every 1h for the next 3h. The results showed that consumption of the experimental cake reduced significantly (p<0.05), 4h post-exercise, the pro-inflammatory protein levels IL-6 and CRP compared to the control group by 50% and 46% respectively. Moreover, in the experimental cake group, the level of the anti-inflammatory cytokine IL-10 was higher by 118%, 4h post-exercise, compared to the control group but not statistically significant.

  12. Proteomics Profiling Reveals Carbohydrate Metabolic Enzymes and 14-3-3 Proteins Play Important Roles for Starch Accumulation during Cassava Root Tuberization

    PubMed Central

    Wang, Xuchu; Chang, Lili; Tong, Zheng; Wang, Dongyang; Yin, Qi; Wang, Dan; Jin, Xiang; Yang, Qian; Wang, Liming; Sun, Yong; Huang, Qixing; Guo, Anping; Peng, Ming

    2016-01-01

    Cassava is one of the most important root crops as a reliable source of food and carbohydrates. Carbohydrate metabolism and starch accumulation in cassava storage root is a cascade process that includes large amounts of proteins and cofactors. Here, comparative proteomics were conducted in cassava root at nine developmental stages. A total of 154 identified proteins were found to be differentially expressed during starch accumulation and root tuberization. Many enzymes involved in starch and sucrose metabolism were significantly up-regulated, and functional classification of the differentially expressed proteins demonstrated that the majority were binding-related enzymes. Many proteins were took part in carbohydrate metabolism to produce energy. Among them, three 14-3-3 isoforms were induced to be clearly phosphorylated during storage root enlargement. Overexpression of a cassava 14-3-3 gene in Arabidopsis thaliana confirmed that the older leaves of these transgenic plants contained higher sugar and starch contents than the wild-type leaves. The 14-3-3 proteins and their binding enzymes may play important roles in carbohydrate metabolism and starch accumulation during cassava root tuberization. These results not only deepened our understanding of the tuberous root proteome, but also uncovered new insights into carbohydrate metabolism and starch accumulation during cassava root enlargement. PMID:26791570

  13. Proteomics Profiling Reveals Carbohydrate Metabolic Enzymes and 14-3-3 Proteins Play Important Roles for Starch Accumulation during Cassava Root Tuberization.

    PubMed

    Wang, Xuchu; Chang, Lili; Tong, Zheng; Wang, Dongyang; Yin, Qi; Wang, Dan; Jin, Xiang; Yang, Qian; Wang, Liming; Sun, Yong; Huang, Qixing; Guo, Anping; Peng, Ming

    2016-01-21

    Cassava is one of the most important root crops as a reliable source of food and carbohydrates. Carbohydrate metabolism and starch accumulation in cassava storage root is a cascade process that includes large amounts of proteins and cofactors. Here, comparative proteomics were conducted in cassava root at nine developmental stages. A total of 154 identified proteins were found to be differentially expressed during starch accumulation and root tuberization. Many enzymes involved in starch and sucrose metabolism were significantly up-regulated, and functional classification of the differentially expressed proteins demonstrated that the majority were binding-related enzymes. Many proteins were took part in carbohydrate metabolism to produce energy. Among them, three 14-3-3 isoforms were induced to be clearly phosphorylated during storage root enlargement. Overexpression of a cassava 14-3-3 gene in Arabidopsis thaliana confirmed that the older leaves of these transgenic plants contained higher sugar and starch contents than the wild-type leaves. The 14-3-3 proteins and their binding enzymes may play important roles in carbohydrate metabolism and starch accumulation during cassava root tuberization. These results not only deepened our understanding of the tuberous root proteome, but also uncovered new insights into carbohydrate metabolism and starch accumulation during cassava root enlargement.

  14. Investigation of carbohydrate and protein metabolism in the digestive organs of the rabbit under the combined influence of vibration, acceleration and irradiation

    NASA Technical Reports Server (NTRS)

    Yuy, R. I.

    1975-01-01

    During spaceflight, the organism is subjected to the influence of various extremal factors such as acceleration, vibration, irradiation, etc. The study of the influence of these factors on metabolism, especially carbohydrate and protein metabolism, in young rabbits is of great significance in simulation experiments. Dynamic factors and irradiation, depending on dose and duration, lead to reduced RNA and protein metabolism.

  15. Requirement for the heart-type fatty acid binding protein in cardiac fatty acid utilization.

    PubMed

    Binas, B; Danneberg, H; McWhir, J; Mullins, L; Clark, A J

    1999-05-01

    Nonenzymatic cytosolic fatty acid binding proteins (FABPs) are abundantly expressed in many animal tissues with high rates of fatty acid metabolism. No physiological role has been demonstrated for any FABP, although these proteins have been implicated in transport of free long-chain fatty acids (LCFAs) and protection against LCFA toxicity. We report here that mice lacking heart-type FABP (H-FABP) exhibit a severe defect of peripheral (nonhepatic, non-fat) LCFA utilization. In these mice, the heart is unable to efficiently take up plasma LCFAs, which are normally its main fuel, and switches to glucose usage. Altered plasma levels of LCFAs, glucose, lactate and beta-hydroxybutyrate are consistent with depressed peripheral LCFA utilization, intensified carbohydrate usage, and increased hepatic LCFA oxidation; these changes are most pronounced under conditions favoring LCFA oxidation. H-FABP deficiency is only incompletely compensated, however, causing acute exercise intolerance and, at old age, a localized cardiac hypertrophy. These data establish a requirement for H-FABP in cardiac intracellular lipid transport and fuel selection and a major role in metabolic homeostasis. This new animal model should be particularly useful for investigating the significance of peripheral LCFA utilization for heart function, insulin sensitivity, and blood pressure.

  16. Probing protein stability with unnatural amino acids

    SciTech Connect

    Mendel, D.; Ellman, J.A.; Zhiyuh Chang; Veenstra, D.L.; Kollman, P.A.; Schultz, P.G. )

    1992-06-26

    Unnatural amino acid mutagenesis, in combination with molecular modeling and simulation techniques, was used to probe the effect of side chain structure on protein stability. Specific replacements at position 133 in T4 lysozyme included (1) leucine (wt), norvaline, ethylglycine, and alanine to measure the cost of stepwise removal of methyl groups from the hydrophobic core, (2) norvaline and O-methyl serine to evaluate the effects of side chain solvation, and (3) leucine, S,S-2-amino-4-methylhexanoic acid, and S-2-amino-3-cyclopentylpropanoic acid to measure the influence of packing density and side chain conformational entropy on protein stability. All of these factors (hydrophobicity, packing, conformational entropy, and cavity formation) significantly influence protein stability and must be considered when analyzing any structural change to proteins.

  17. Increase in the carbohydrate content of the microalgae Spirulina in culture by nutrient starvation and the addition of residues of whey protein concentrate.

    PubMed

    Vieira Salla, Ana Cláudia; Margarites, Ana Cláudia; Seibel, Fábio Ivan; Holz, Luiz Carlos; Brião, Vandré Barbosa; Bertolin, Telma Elita; Colla, Luciane Maria; Costa, Jorge Alberto Vieira

    2016-06-01

    Non-renewable sources that will end with time are the largest part of world energy consumption, which emphasizes the necessity to develop renewable sources of energy. This necessity has created opportunities for the use of microalgae as a biofuel. The use of microalgae as a feedstock source for bioethanol production requires high yields of both biomass and carbohydrates. With mixotrophic cultures, wastewater can be used to culture algae. The aim of the study was to increase the carbohydrate content in the microalgae Spirulina with the additions of residues from the ultra and nanofiltration of whey protein. The nutrient deficit in the Zarrouk medium diluted to 20% and the addition of 2.5% of both residue types led to high carbohydrate productivity (60 mg L(-1) d(-1)). With these culture conditions, the increase in carbohydrate production in Spirulina indicated that the conditions were appropriate for use with microalgae as a feedstock in the production of bioethanol.

  18. Stereoselective synthesis of light-activatable perfluorophenylazide-conjugated carbohydrates for glycoarray fabrication and evaluation of structural effects on protein binding by SPR imaging†

    PubMed Central

    Deng, Lingquan; Norberg, Oscar; Uppalapati, Suji; Yan, Mingdi; Ramström, Olof

    2014-01-01

    A series of light-activatable perfluorophenylazide (PFPA)-conjugated carbohydrate structures have been synthesized and applied to glycoarray fabrication. The glycoconjugates were structurally varied with respect to anomeric attachment, S-, and O-linked carbohydrates, respectively, as well as linker structure and length. Efficient stereoselective synthetic routes were developed, leading to the formation of the PFPA-conjugated structures in good yields over few steps. The use of glycosyl thiols as donors proved especially efficient and provided the final compounds in up to 70% total yield with high anomeric purities. PFPA-based photochemistry was subsequently used to generate carbohydrate arrays on a polymeric surface, and surface plasmon resonance imaging (SPRi) was applied for evaluation of carbohydrate-protein interactions using the plant lectin Concanavalin A (Con A) as a probe. The results indicate better performance and equal efficiency of S- and O-linked structures with intermediate linker length. PMID:21423935

  19. Efficacy of azelaic acid on hepatic key enzymes of carbohydrate metabolism in high fat diet induced type 2 diabetic mice.

    PubMed

    Muthulakshmi, Shanmugam; Saravanan, Ramalingam

    2013-06-01

    Azelaic acid (AzA), a C9 linear α,ω-dicarboxylic acid, is found in whole grains namely wheat, rye, barley, oat seeds and sorghum. The study was performed to investigate whether AzA exerts beneficial effect on hepatic key enzymes of carbohydrate metabolism in high fat diet (HFD) induced type 2 diabetic C57BL/6J mice. C57BL/6J mice were fed high fat diet for 10 weeks and subjected to intragastric administration of various doses (20 mg, 40 mg and 80 mg/kg BW) of AzA daily for the subsequent 5 weeks. Rosiglitazone (RSG) was used as reference drug. Body weight, food intake, plasma glucose, plasma insulin, blood haemoglobin (Hb), blood glycosylated haemoglobin (HbA1c), liver glycolytic enzyme (hexokinase), hepatic shunt enzyme (glucose-6-phosphate dehydrogenase), gluconeogenic enzymes(glucose-6-phosphatase and fructose-1,6-bisphosphatase), liver glycogen, plasma and liver triglycerides were examined in mice fed with normal standard diet (NC), high fat diet (HFD), HFD with AzA (HFD + AzA) and HFD with rosiglitazone (HFD + RSG). Among the three doses, 80 mg/kg BW of AzA was able to positively regulate plasma glucose, insulin, blood HbA1c and haemoglobin levels by significantly increasing the activity of hexokinase and glucose-6-phosphate dehydrogenase and significantly decreasing the activity of glucose-6-phosphatase and fructose-1,6-bisphosphatase thereby increasing the glycogen content in the liver. From this study, we put forward that AzA could significantly restore the levels of plasma glucose, insulin, HbA1c, Hb, liver glycogen and carbohydrate metabolic key enzymes to near normal in diabetic mice and hence, AzA may be useful as a biomaterial in the development of therapeutic agents against high fat diet induced T2DM.

  20. Effects of intravenously administered fructose and glucose on splanchnic amino acid and carbohydrate metabolism in hypertriglyceridemic men.

    PubMed Central

    Wolfe, B M; Ahuja, S P; Marliss, E B

    1975-01-01

    Splanchnic metabolism was studied in the fed state during prolonged intravenous administration (30 g/h) of either fructose or glucose to hypertriglyceridemic men who had been maintained on a high-carbohydrate diet for 2 wk. Splanchnic exchange of amino acids and carbohydrates was quantified by measurement of splanchnic flow and of blood or plasma arteriohepatic venous concentration gradients. Results obtained in subjects receiving fructose were compared with those obtained in (a) similar subjects receiving glucose and (b) postabsorptive controls maintained on isocaloric, balanced diets. Mean arterial plasma levels of alanine, glycine, serine, threonine, methionine, proline, valine, leucine, histidine, lysine, and ornithine were significantly higher in subjects given fructose than in those give glucose (P less than 0.05). The mean arterial concentration and splanchnic uptake of alanine were significantly higher in subjects given fructose than in postabsorptive controls, despite a significantly lower fractional extraction of alanine in the former (P less than 0.05). The mean arterial plasma levels of serine and ornithine were significantly lower in subjects receiving fructose than in postabsorptive controls (P less than 0.05). About half of the administered fructose or glucose was taken up in the splanchnic region, where approximately 15% was converted to CO2 and 10% to lactate. Half of the fructose taken up in the splanchnic region was converted to glucose released from the liver. The amount of hexose carbon remaining for hepatic synthesis of liquids in subjects given fructose was less than half of that of subjects given glucose. These studies demonstrate that fructose and glucose have divergent effects on amino acid metabolism and that during hypercaloric infusion of glucose (as with fructose), the human liver is a major site of lactate production. PMID:1159097

  1. Catalytic air oxidation of biomass-derived carbohydrates to formic acid.

    PubMed

    Li, Jiang; Ding, Dao-Jun; Deng, Li; Guo, Qing-Xiang; Fu, Yao

    2012-07-01

    An efficient catalytic system for biomass oxidation to form formic acid was developed. The conversion of glucose to formic acid can reach up to 52% yield within 3 h when catalyzed by 5 mol% of H(5)PV(2)Mo(10)O(40) at only 373 K using air as the oxidant. Furthermore, the heteropolyacid can be used as a bifunctional catalyst in the conversion of cellulose to formic acid (yield=35%) with air as the oxidant. PMID:22499553

  2. Catalytic air oxidation of biomass-derived carbohydrates to formic acid.

    PubMed

    Li, Jiang; Ding, Dao-Jun; Deng, Li; Guo, Qing-Xiang; Fu, Yao

    2012-07-01

    An efficient catalytic system for biomass oxidation to form formic acid was developed. The conversion of glucose to formic acid can reach up to 52% yield within 3 h when catalyzed by 5 mol% of H(5)PV(2)Mo(10)O(40) at only 373 K using air as the oxidant. Furthermore, the heteropolyacid can be used as a bifunctional catalyst in the conversion of cellulose to formic acid (yield=35%) with air as the oxidant.

  3. Simultaneous analysis of carbohydrates and organic acids by HPLC-DAD-RI for monitoring goat's milk yogurts fermentation.

    PubMed

    da Costa, Marion Pereira; Frasao, Beatriz da Silva; Lima, Bruno Reis Carneiro da Costa; Rodrigues, Bruna Leal; Conte Junior, Carlos Adam

    2016-05-15

    During yogurt manufacture, the lactose fermentation and organic acid production can be used to monitor the fermentation process by starter cultures and probiotic bacteria. In the present work, a simple, sensitive and reproducible high-performance liquid chromatography with dual detectors, diode array detector and refractive index was validated by simultaneous analysis of carbohydrates and organic acids in goat milk yogurts. In addition, pH and bacterial analysis were performed. Separation of all the compounds was performed on an Aminex HPX-87H column (300×7.8 mm, 9 µm) utilizing a 3 mmol L(-1) sulfuric acid aqueous mobile phase under isocratic conditions. Lactose, glucose, galactose, citric, lactic and formic acids were used to evaluate the following performance parameters: selectivity, linearity, precision, limit of detection (LOD), limit of quantification (LOQ), decision limits (CCα), detection capabilities (CCβ), recovery and robustness. For the method application a six goat milk yogurts were elaborated: natural, probiotic, prebiotic, symbiotic, cupuassu fruit pulp, and probiotic with cupuassu fruit pulp. The validated method presented an excellent selectivity with no significant matrix effect, and a broad linear study range with coefficients of determination higher than 0.995. The relative standard deviation was lower than 10% under repeatability and within-laboratory reproducibility conditions for the studied analytes. The LOD of the method was defined from 0.001 to 0.003 µg g(-1), and the LOQ from 0.003 to 0.013 µg g(-1). The CCα was ranged from 0.032 to 0.943 µg g(-1), and the CCβ from 0.053 to 1.604 µg g(-1). The obtained recovery values were from 78% to 119%. In addition, the method exhibited an appropriate robustness for all parameter evaluated. Base in our data, it was concluded that the performance parameters demonstrated total method adequacy for the detection and quantification of carbohydrates and organic acids in goat milk yogurts. The

  4. Simultaneous analysis of carbohydrates and organic acids by HPLC-DAD-RI for monitoring goat's milk yogurts fermentation.

    PubMed

    da Costa, Marion Pereira; Frasao, Beatriz da Silva; Lima, Bruno Reis Carneiro da Costa; Rodrigues, Bruna Leal; Conte Junior, Carlos Adam

    2016-05-15

    During yogurt manufacture, the lactose fermentation and organic acid production can be used to monitor the fermentation process by starter cultures and probiotic bacteria. In the present work, a simple, sensitive and reproducible high-performance liquid chromatography with dual detectors, diode array detector and refractive index was validated by simultaneous analysis of carbohydrates and organic acids in goat milk yogurts. In addition, pH and bacterial analysis were performed. Separation of all the compounds was performed on an Aminex HPX-87H column (300×7.8 mm, 9 µm) utilizing a 3 mmol L(-1) sulfuric acid aqueous mobile phase under isocratic conditions. Lactose, glucose, galactose, citric, lactic and formic acids were used to evaluate the following performance parameters: selectivity, linearity, precision, limit of detection (LOD), limit of quantification (LOQ), decision limits (CCα), detection capabilities (CCβ), recovery and robustness. For the method application a six goat milk yogurts were elaborated: natural, probiotic, prebiotic, symbiotic, cupuassu fruit pulp, and probiotic with cupuassu fruit pulp. The validated method presented an excellent selectivity with no significant matrix effect, and a broad linear study range with coefficients of determination higher than 0.995. The relative standard deviation was lower than 10% under repeatability and within-laboratory reproducibility conditions for the studied analytes. The LOD of the method was defined from 0.001 to 0.003 µg g(-1), and the LOQ from 0.003 to 0.013 µg g(-1). The CCα was ranged from 0.032 to 0.943 µg g(-1), and the CCβ from 0.053 to 1.604 µg g(-1). The obtained recovery values were from 78% to 119%. In addition, the method exhibited an appropriate robustness for all parameter evaluated. Base in our data, it was concluded that the performance parameters demonstrated total method adequacy for the detection and quantification of carbohydrates and organic acids in goat milk yogurts. The

  5. Malectin: A Novel Carbohydrate-binding Protein of the Endoplasmic Reticulum and a Candidate Player in the Early Steps of Protein N-Glycosylation

    PubMed Central

    Schallus, Thomas; Jaeckh, Christine; Fehér, Krisztina; Palma, Angelina S.; Liu, Yan; Simpson, Jeremy C.; Mackeen, Mukram; Stier, Gunter; Gibson, Toby J.; Feizi, Ten; Pieler, Tomas

    2008-01-01

    N-Glycosylation starts in the endoplasmic reticulum (ER) where a 14-sugar glycan composed of three glucoses, nine mannoses, and two N-acetylglucosamines (Glc3Man9GlcNAc2) is transferred to nascent proteins. The glucoses are sequentially trimmed by ER-resident glucosidases. The Glc3Man9GlcNAc2 moiety is the substrate for oligosaccharyltransferase; the Glc1Man9GlcNAc2 and Man9GlcNAc2 intermediates are signals for glycoprotein folding and quality control in the calnexin/calreticulin cycle. Here, we report a novel membrane-anchored ER protein that is highly conserved in animals and that recognizes the Glc2-N-glycan. Structure determination by nuclear magnetic resonance showed that its luminal part is a carbohydrate binding domain that recognizes glucose oligomers. Carbohydrate microarray analyses revealed a uniquely selective binding to a Glc2-N-glycan probe. The localization, structure, and binding specificity of this protein, which we have named malectin, open the way to studies of its role in the genesis, processing and secretion of N-glycosylated proteins. PMID:18524852

  6. Z-sinapinic acid: the change of the stereochemistry of cinnamic acids as rational synthesis of a new matrix for carbohydrate MALDI-MS analysis.

    PubMed

    Salum, María L; Itovich, Lucia M; Erra-Balsells, Rosa

    2013-11-01

    Successful application of matrix-assisted laser desorption/ionization (MALDI) MS started with the introduction of efficient matrices such as cinnamic acid derivatives (i.e. 3,5-dimethoxy-4-hydroxycinnamic acid, SA; α-cyano-4-hydroxycinnamic acid). Since the empirical founding of these matrices, other commercial available cinnamic acids with different nature and location of substituents at benzene ring were attempted. Rational design and synthesis of new cinnamic acids have been recently described too. Because the presence of a rigid double bond in its molecule structure, cinnamic acids can exist as two different geometric isomers, the E-form and Z-form. Commercial available cinnamic acids currently used as matrices are the geometric isomers trans or E (E-cinnamic and trans-cinnamic acids). As a new rational design of MALDI matrices, Z-cinnamic acids were synthesized, and their properties as matrices were studied. Their performance was compared with that of the corresponding E-isomer and classical crystalline matrices (3,5-dihydroxybenzoic acid; norharmane) in the analysis of neutral/sulfated carbohydrates. Herein, we demonstrate the outstanding performance for Z-SA. Sulfated oligosaccharides were detected in negative ion mode, and the dissociation of sulfate groups was almost suppressed. Additionally, to better understand the quite different performance of each geometric isomer as matrix, the physical and morphological properties as well as the photochemical stability in solid state were studied. The influence of the E/Z photoisomerization of the matrix during MALDI was evaluated. Finally, molecular modeling (density functional theory study) of the optimized geometry and stereochemistry of E-cinnamic and Z-cinnamic acids revealed some factors governing the analyte-matrix interaction.

  7. Glucose intolerance induced by a high-fat/low-carbohydrate diet in rats effects of nonesterified fatty acids.

    PubMed

    Wang, Yuan; Miura, Yoshikazu; Kaneko, Takashi; Li, Jue; Qin, Li-Qiang; Wang, Pei-Yu; Matsui, Hisao; Sato, Akio

    2002-04-01

    We examined the time course of effects of a high-fat/low-carbohydrate (HF/LC) diet on the impairment of glucose tolerance in rats, clarified whether insulin secretion and sensitivity were impaired by the HF/LC diet, and investigated the relationship between the increased nonesterified fatty acids (NEFA) after HF/LC diet feeding and insulin secretion and sensitivity. We found that glucose tolerance and the postglucose-loading insulin secretion were impaired after 3 and 7 d on the HF/LC diet. The glucose intolerance was accompanied by a rise in the fasting plasma NEFA level. When stimulated with 15 mmol/L of glucose, the insulin secretion was impaired in pancreatic islets from rats fed the HF/LC diet. Rats fed the HF/LC diet showed insulin resistance in vivo. The glucose-stimulated insulin secretion was inhibited in the islets following 24-h culture with palmitic acid. The 24-h infusion of palmitic acid decreased whole-body insulin sensitivity. In summary, at least 3 d on a HF/LC diet is needed to induce glucose intolerance in rats, and the impairment may be induced by decreased insulin secretion and sensitivity, which is related to the increase in the plasma NEFA level. PMID:12108518

  8. Efficacy and Safety of a High Protein, Low Carbohydrate Diet for Weight Loss in Severely Obese Adolescents

    PubMed Central

    Krebs, Nancy F.; Gao, Dexiang; Gralla, Jane; Collins, Juliet S.; Johnson, Susan L.

    2010-01-01

    Objective To evaluate the efficacy and safety of a carbohydrate restricted versus a low fat diet on weight loss, metabolic markers, body composition, and cardiac function tests in severely obese adolescents. Study design Subjects were randomized to one of two diets: a high protein, low carbohydrate (20 g/day) diet (HPLC) or low fat (30% of calories) (LF) regimen for 13 weeks; close monitoring was maintained to evaluate safety. After the intervention, no clinical contact was made until follow-up measurements were obtained at 24 and 36 weeks from baseline. The primary outcome was change in BMI-Z-score at 13, 24, and 36 weeks. Results Forty-six subjects (24 HPLC, 22 in LF) initiated and 33 subjects completed the intervention; follow-up data were available on approximately half of the subjects. Significant reduction in BMI-Z-score (BMI-Z) was achieved in both groups during intervention, and was significantly greater for the HPLC group (p=0.03). Both groups maintained significant BMI-Z reduction at follow-up; changes were not significantly different between groups. Loss of lean body mass was not spared in the HPLC group. No serious adverse effects were observed related to metabolic profiles, cardiac function, or subjective complaints. Conclusions The HPLC diet is a safe and effective option for medically supervised weight loss in severely obese adolescents. PMID:20304413

  9. Developmentally regulated changes in glucosidase II association with, and carbohydrate content of, the protein tyrosine phosphatase CD45.

    PubMed

    Baldwin, T A; Ostergaard, H L

    2001-10-01

    Glucosidase II (GII) stably interacts with the external domain of CD45 in a carbohydrate-dependent manner. We have found that the association occurs in immature cells, but is significantly reduced in mature T cells. Using mannose-binding protein (MBP), in both FACS analysis and pull-down assays, we find that MBP can specifically recognize cell surface CD45 from immature, but not mature T cells. Analysis of thymocytes reveals increased MBP binding and GII association with CD45 in double-positive thymocytes compared with either double-negative or single-positive thymocytes. As well, the same pool of CD45 recognized by MBP can also associate with GII. Initial analysis of the basis of the interaction between CD45 and MBP suggests MBP binds two different glycoforms of CD45 based on the differential competition with glucose. Finally, inhibition of GII activity in cells that do not normally express MBP ligands results in significant increases in cell surface MBP ligands, including CD45. Taken together, these data suggest that the glucose content of the cell surface CD45 changes as thymocytes undergo maturation to mature T cells, and may be regulated by GII interactions. Such changes in the cell surface carbohydrate on CD45 may affect the development of thymocytes, perhaps via binding of CD45 on thymocytes to lectins on stromal cells. PMID:11564800

  10. In Situ Expression of Acidic and Thermophilic Carbohydrate Active Enzymes by Filamentous Fungi (JGI Seventh Annual User Meeting 2012: Genomics of Energy and Environment)

    ScienceCinema

    Mosier, Annika [Stanford University

    2016-07-12

    Annika Mosier, graduate student from Stanford University presents a talk titled "In Situ Expression of Acidic and Thermophilic Carbohydrate Active Enzymes by Filamentous Fungi" at the JGI User 7th Annual Genomics of Energy & Environment Meeting on March 22, 2012 in Walnut Creek, Calif

  11. In Situ Expression of Acidic and Thermophilic Carbohydrate Active Enzymes by Filamentous Fungi (JGI Seventh Annual User Meeting 2012: Genomics of Energy and Environment)

    SciTech Connect

    Mosier, Annika

    2012-03-22

    Annika Mosier, graduate student from Stanford University presents a talk titled "In Situ Expression of Acidic and Thermophilic Carbohydrate Active Enzymes by Filamentous Fungi" at the JGI User 7th Annual Genomics of Energy & Environment Meeting on March 22, 2012 in Walnut Creek, Calif

  12. Arabidopsis G-protein interactome reveals connections to cell wall carbohydrates and morphogenesis.

    PubMed

    Klopffleisch, Karsten; Phan, Nguyen; Augustin, Kelsey; Bayne, Robert S; Booker, Katherine S; Botella, Jose R; Carpita, Nicholas C; Carr, Tyrell; Chen, Jin-Gui; Cooke, Thomas Ryan; Frick-Cheng, Arwen; Friedman, Erin J; Fulk, Brandon; Hahn, Michael G; Jiang, Kun; Jorda, Lucia; Kruppe, Lydia; Liu, Chenggang; Lorek, Justine; McCann, Maureen C; Molina, Antonio; Moriyama, Etsuko N; Mukhtar, M Shahid; Mudgil, Yashwanti; Pattathil, Sivakumar; Schwarz, John; Seta, Steven; Tan, Matthew; Temp, Ulrike; Trusov, Yuri; Urano, Daisuke; Welter, Bastian; Yang, Jing; Panstruga, Ralph; Uhrig, Joachim F; Jones, Alan M

    2011-09-27

    The heterotrimeric G-protein complex is minimally composed of Gα, Gβ, and Gγ subunits. In the classic scenario, the G-protein complex is the nexus in signaling from the plasma membrane, where the heterotrimeric G-protein associates with heptahelical G-protein-coupled receptors (GPCRs), to cytoplasmic target proteins called effectors. Although a number of effectors are known in metazoans and fungi, none of these are predicted to exist in their canonical forms in plants. To identify ab initio plant G-protein effectors and scaffold proteins, we screened a set of proteins from the G-protein complex using two-hybrid complementation in yeast. After deep and exhaustive interrogation, we detected 544 interactions between 434 proteins, of which 68 highly interconnected proteins form the core G-protein interactome. Within this core, over half of the interactions comprising two-thirds of the nodes were retested and validated as genuine in planta. Co-expression analysis in combination with phenotyping of loss-of-function mutations in a set of core interactome genes revealed a novel role for G-proteins in regulating cell wall modification.

  13. Arabidopsis G-protein interactome reveals connections to cell wall carbohydrates and morphogenesis

    PubMed Central

    Klopffleisch, Karsten; Phan, Nguyen; Augustin, Kelsey; Bayne, Robert S; Booker, Katherine S; Botella, Jose R; Carpita, Nicholas C; Carr, Tyrell; Chen, Jin-Gui; Cooke, Thomas Ryan; Frick-Cheng, Arwen; Friedman, Erin J; Fulk, Brandon; Hahn, Michael G; Jiang, Kun; Jorda, Lucia; Kruppe, Lydia; Liu, Chenggang; Lorek, Justine; McCann, Maureen C; Molina, Antonio; Moriyama, Etsuko N; Mukhtar, M Shahid; Mudgil, Yashwanti; Pattathil, Sivakumar; Schwarz, John; Seta, Steven; Tan, Matthew; Temp, Ulrike; Trusov, Yuri; Urano, Daisuke; Welter, Bastian; Yang, Jing; Panstruga, Ralph; Uhrig, Joachim F; Jones, Alan M

    2011-01-01

    The heterotrimeric G-protein complex is minimally composed of Gα, Gβ, and Gγ subunits. In the classic scenario, the G-protein complex is the nexus in signaling from the plasma membrane, where the heterotrimeric G-protein associates with heptahelical G-protein-coupled receptors (GPCRs), to cytoplasmic target proteins called effectors. Although a number of effectors are known in metazoans and fungi, none of these are predicted to exist in their canonical forms in plants. To identify ab initio plant G-protein effectors and scaffold proteins, we screened a set of proteins from the G-protein complex using two-hybrid complementation in yeast. After deep and exhaustive interrogation, we detected 544 interactions between 434 proteins, of which 68 highly interconnected proteins form the core G-protein interactome. Within this core, over half of the interactions comprising two-thirds of the nodes were retested and validated as genuine in planta. Co-expression analysis in combination with phenotyping of loss-of-function mutations in a set of core interactome genes revealed a novel role for G-proteins in regulating cell wall modification. PMID:21952135

  14. Arabidopsis G-protein interactome reveals connections to cell wall carbohydrates and morphogenesis

    SciTech Connect

    Klopffleisch, Karsten; Phan, Nguyen; Chen, Jay; Panstruga, Ralph; Uhrig, Joachim; Jones, Alan M

    2011-01-01

    The heterotrimeric G-protein complex is minimally composed of G{alpha}, G{beta}, and G{gamma} subunits. In the classic scenario, the G-protein complex is the nexus in signaling from the plasma membrane, where the heterotrimeric G-protein associates with heptahelical G-protein-coupled receptors (GPCRs), to cytoplasmic target proteins called effectors. Although a number of effectors are known in metazoans and fungi, none of these are predicted to exist in their canonical forms in plants. To identify ab initio plant G-protein effectors and scaffold proteins, we screened a set of proteins from the G-protein complex using two-hybrid complementation in yeast. After deep and exhaustive interrogation, we detected 544 interactions between 434 proteins, of which 68 highly interconnected proteins form the core G-protein interactome. Within this core, over half of the interactions comprising two-thirds of the nodes were retested and validated as genuine in planta. Co-expression analysis in combination with phenotyping of loss-of-function mutations in a set of core interactome genes revealed a novel role for G-proteins in regulating cell wall modification.

  15. Effects of fat, protein, and carbohydrate and protein load on appetite, plasma cholecystokinin, peptide YY, and ghrelin, and energy intake in lean and obese men.

    PubMed

    Brennan, Ixchel M; Luscombe-Marsh, Natalie D; Seimon, Radhika V; Otto, Bärbel; Horowitz, Michael; Wishart, Judith M; Feinle-Bisset, Christine

    2012-07-01

    While protein is regarded as the most satiating macronutrient, many studies have employed test meals that had very high and unsustainable protein contents. Furthermore, the comparative responses between lean and obese subjects and the relationships between energy intake suppression and gut hormone release remain unclear. We evaluated the acute effects of meals with modest variations in 1) fat, protein, and carbohydrate content and 2) protein load on gastrointestinal hormones, appetite, and subsequent energy intake in lean and obese subjects. Sixteen lean and sixteen obese men were studied on four occasions. Following a standardized breakfast, they received for lunch: 1) high-fat (HF), 2) high-protein (HP), 3) high-carbohydrate/low-protein (HC/LP), or 4) adequate-protein (AP) isocaloric test meals. Hunger, fullness, and gut hormones were measured throughout, and at t = 180 min energy intake at a buffet meal was quantified. In lean subjects, hunger was less and fullness greater following HF, HP, and AP compared with HC/LP meals, and energy intake was less following HF and HP compared with HC meals (P < 0.05). In the obese subjects, hunger was less following HP compared with HF, HC/LP, and AP meals, and energy intake was less following HP and AP compared with HF and HC meals (P < 0.05). There were no major differences in hormone responses to the meals among subject groups, but the CCK and ghrelin responses to HP and AP were sustained in both groups. In conclusion, HP meals suppress energy intake in lean and obese subjects, an effect potentially mediated by CCK and ghrelin, while obese individuals appear to be less sensitive to the satiating effects of fat.

  16. Glyco-gold nanoparticle shapes enhance carbohydrate-protein interactions in mammalian cells

    NASA Astrophysics Data System (ADS)

    Sangabathuni, Sivakoti; Vasudeva Murthy, Raghavendra; Chaudhary, Preeti Madhukar; Surve, Manalee; Banerjee, Anirban; Kikkeri, Raghavendra

    2016-06-01

    Advances in shape-dependent nanoparticle (NP) research have prompted a close scrutiny of the behaviour of nanostructures in vitro and in vivo. Data pertaining to cellular uptake and site specific sequestration of different shapes of NPs will undoubtedly assist researchers to design better nano-probes for therapeutic and imaging purposes. Herein, we investigated the shape dependent uptake of glyco-gold nanoparticles (G-AuNPs) in different cancer cell lines. Specifically, we have compared the behaviour of spherical, rod and star AuNPs with mannose and galactose conjugations. In vitro experiments showed that the rod-AuNPs exhibited the highest uptake over that of the star and spherical counterparts. Further, an investigation of the mechanism of the uptake clearly demonstrated clathrin mediated endocytosis of the specific G-AuNPs. These results reveal the benefits of different G-AuNP shapes in carbohydrate-mediated interactions.Advances in shape-dependent nanoparticle (NP) research have prompted a close scrutiny of the behaviour of nanostructures in vitro and in vivo. Data pertaining to cellular uptake and site specific sequestration of different shapes of NPs will undoubtedly assist researchers to design better nano-probes for therapeutic and imaging purposes. Herein, we investigated the shape dependent uptake of glyco-gold nanoparticles (G-AuNPs) in different cancer cell lines. Specifically, we have compared the behaviour of spherical, rod and star AuNPs with mannose and galactose conjugations. In vitro experiments showed that the rod-AuNPs exhibited the highest uptake over that of the star and spherical counterparts. Further, an investigation of the mechanism of the uptake clearly demonstrated clathrin mediated endocytosis of the specific G-AuNPs. These results reveal the benefits of different G-AuNP shapes in carbohydrate-mediated interactions. Electronic supplementary information (ESI) available. See DOI: 10.1039/c6nr03008d

  17. Detection of non-protein amino acids in the presence of protein amino acids. II.

    NASA Technical Reports Server (NTRS)

    Shapshak, P.; Okaji, M.

    1972-01-01

    Studies conducted with the JEOL 5AH amino acid analyzer are described. This instrument makes possible the programming of the chromatographic process. Data are presented showing the separations of seventeen non-protein amino acids in the presence of eighteen protein amino acids. It is pointed out that distinct separations could be obtained in the case of a number of chemically similar compounds, such as ornithine and lysine, N-amidino alanine and arginine, and iminodiacetic acid and S-carboxymethyl cysteine and aspartic acid.

  18. The effects of high fat, low carbohydrate and low fat, high carbohydrate diets on tumor necrosis factor superfamily proteins and proinflammatory cytokines in C57BL/6 mice.

    PubMed

    Sirjani, Mahshid; Taleban, Foroogh Azam; Hekmatdoost, Azita; Amiri, Zohreh; Pellizzon, Michael; Hedayati, Mehdi; Bidad, Katayoon; Shokouhi Shoormasti, Raheleh; Pourpak, Zahra

    2014-08-01

    There has been considerable inconsistency regarding the potential relationship between dyslipidemia and bone metabolism. The inflammatory stimulation through the receptor activator of the nuclear factor kappa-B ligand (RANKL)/ receptor activator of the nuclear factor kappa-B (RANK)/ osteoprotegerin (OPG) pathway could be the infrastructural mechanism for hypercholesterolemia-induced bone loss.In this study, we investigated the effect of dyslipidemia on RANKL and OPG alongside with pro-inflammatory cytokines. Thirty male C57Bl/6 mice (4 weeks old) were randomized to two purified diet groups (15 animals in each group), high fat, low carbohydrate diet (HFLCD) and its matched low fat, high carbohydrate diet (LFHCD). After 12 weeks of feeding in standard situations, the plasma concentration of lipid profile, interleukin (IL) 1Beta, IL-6, tumor necrosis factor-alpha (TNF-α) and RANKL, OPG, and RANKL: OPG ratio were measured.In the present study, although the body weight significantly increased during 12 weeks in HFLCD and LFHCD groups, there were no significant differences in food intake, food efficiency ratio and weight gain between the two groups. The LFHCD group had significantly higher median RANKL and RANKL/OPG ratio. There was no significant difference in plasma IL-1β, IL-6 and TNF-α concentration between LFHCD and HFLCD groups.These unexpected findings from LFHCD, that seem to be as a result of its higher carbohydrate proportion in comparison to HFLCD, implicate dietary carbohydrate rather than dietary fat as a more significant nutritional factor contributing to change in RANKL level and RANKL: OPG ratio.

  19. Cyclic Sulfamidate Enabled Syntheses of Amino Acids, Peptides, Carbohydrates, and Natural Products

    EPA Science Inventory

    This article reviews the emergence of cyclic sulfamidates as versatile intermediatesfor the synthesis of unnatural amino acids, chalcogen peptides, modified sugars, drugs and drug candidates, and important natural products.

  20. Analysis of carbohydrates and amino acids in vegetable waste waters by ion chromatography.

    PubMed

    Arienzo, Michele; De Martino, Antonio; Capasso, Renato; Di Maro, Antimo; Parente, Augusto

    2003-01-01

    High-performance anion exchange chromatography coupled with pulsed amperometric detection was used for the quantitative determination of total and free sugars in olive oil mill waste waters (OMWW). Automated amino acid ion chromatography was employed to analyse total and free amino acids in the same OMWW. Sugars were analysed in samples pre-purified by means of a three-step purification procedure involving: (i) methanol precipitation of OMWW; (ii) dialysis of the obtained solid and liquid fractions; and (iii) chromatographic purification on RP18 phase followed by Amberlite resin. The amino acids were determined directly in samples obtained from the first two steps performed for sugar analysis. The analysis carried out with the reported methodologies allowed the quantitative determination of total sugars and amino acids and the differentiation between their free and bound forms. The sugars determined were arabinose, fructose, galactose, glucose, rhamnose, xylose, galacturonic and glucuronic acids, and the amino acids were Asp, Glu, Thr, Ser, Pro, Gly, Ala, Val, Met, Ile, Leu, Tyr, Phe, Lys, His, Arg and Cys. Asn, Gin, and Trp were not detected. The technological, biotechnological and environmental advantages arising from this analytical methodology applied to OMWW are briefly discussed.

  1. A glycoconjugate of Haemophilus influenzae Type b capsular polysaccharide with tetanus toxoid protein: hydrodynamic properties mainly influenced by the carbohydrate.

    PubMed

    Abdelhameed, Ali Saber; Adams, Gary G; Morris, Gordon A; Almutairi, Fahad M; Duvivier, Pierre; Conrath, Karel; Harding, Stephen E

    2016-02-26

    Three important physical properties which may affect the performance of glycoconjugate vaccines against serious disease are molar mass (molecular weight), heterogeneity (polydispersity), and conformational flexibility in solution. The dilute solution behaviour of native and activated capsular polyribosylribitol (PRP) polysaccharides extracted from Haemophilus influenzae type b (Hib), and the corresponding glycoconjugate made by conjugating this with the tetanus toxoid (TT) protein have been characterized and compared using a combination of sedimentation equilibrium and sedimentation velocity in the analytical ultracentrifuge with viscometry. The weight average molar mass of the activated material was considerably reduced (Mw ~ 0.24 × 10(6) g.mol(-1)) compared to the native (Mw ~ 1.2 × 10(6) g.mol(-1)). Conjugation with the TT protein yielded large polydisperse structures (of Mw ~ 7.4 × 10(6) g.mol(-1)), but which retained the high degree of flexibility of the native and activated polysaccharide, with frictional ratio, intrinsic viscosity, sedimentation conformation zoning behaviour and persistence length all commensurate with highly flexible coil behaviour and unlike the previously characterised tetanus toxoid protein (slightly extended and hydrodynamically compact structure with an aspect ratio of ~3). This non-protein like behaviour clearly indicates that it is the carbohydrate component which mainly influences the physical behaviour of the glycoconjugate in solution.

  2. A glycoconjugate of Haemophilus influenzae Type b capsular polysaccharide with tetanus toxoid protein: hydrodynamic properties mainly influenced by the carbohydrate

    PubMed Central

    Abdelhameed, Ali Saber; Adams, Gary G.; Morris, Gordon A.; Almutairi, Fahad M.; Duvivier, Pierre; Conrath, Karel; Harding, Stephen E.

    2016-01-01

    Three important physical properties which may affect the performance of glycoconjugate vaccines against serious disease are molar mass (molecular weight), heterogeneity (polydispersity), and conformational flexibility in solution. The dilute solution behaviour of native and activated capsular polyribosylribitol (PRP) polysaccharides extracted from Haemophilus influenzae type b (Hib), and the corresponding glycoconjugate made by conjugating this with the tetanus toxoid (TT) protein have been characterized and compared using a combination of sedimentation equilibrium and sedimentation velocity in the analytical ultracentrifuge with viscometry. The weight average molar mass of the activated material was considerably reduced (Mw ~ 0.24 × 106 g.mol−1) compared to the native (Mw ~ 1.2 × 106 g.mol−1). Conjugation with the TT protein yielded large polydisperse structures (of Mw ~ 7.4 × 106 g.mol−1), but which retained the high degree of flexibility of the native and activated polysaccharide, with frictional ratio, intrinsic viscosity, sedimentation conformation zoning behaviour and persistence length all commensurate with highly flexible coil behaviour and unlike the previously characterised tetanus toxoid protein (slightly extended and hydrodynamically compact structure with an aspect ratio of ~3). This non-protein like behaviour clearly indicates that it is the carbohydrate component which mainly influences the physical behaviour of the glycoconjugate in solution. PMID:26915577

  3. A glycoconjugate of Haemophilus influenzae Type b capsular polysaccharide with tetanus toxoid protein: hydrodynamic properties mainly influenced by the carbohydrate.

    PubMed

    Abdelhameed, Ali Saber; Adams, Gary G; Morris, Gordon A; Almutairi, Fahad M; Duvivier, Pierre; Conrath, Karel; Harding, Stephen E

    2016-01-01

    Three important physical properties which may affect the performance of glycoconjugate vaccines against serious disease are molar mass (molecular weight), heterogeneity (polydispersity), and conformational flexibility in solution. The dilute solution behaviour of native and activated capsular polyribosylribitol (PRP) polysaccharides extracted from Haemophilus influenzae type b (Hib), and the corresponding glycoconjugate made by conjugating this with the tetanus toxoid (TT) protein have been characterized and compared using a combination of sedimentation equilibrium and sedimentation velocity in the analytical ultracentrifuge with viscometry. The weight average molar mass of the activated material was considerably reduced (Mw ~ 0.24 × 10(6) g.mol(-1)) compared to the native (Mw ~ 1.2 × 10(6) g.mol(-1)). Conjugation with the TT protein yielded large polydisperse structures (of Mw ~ 7.4 × 10(6) g.mol(-1)), but which retained the high degree of flexibility of the native and activated polysaccharide, with frictional ratio, intrinsic viscosity, sedimentation conformation zoning behaviour and persistence length all commensurate with highly flexible coil behaviour and unlike the previously characterised tetanus toxoid protein (slightly extended and hydrodynamically compact structure with an aspect ratio of ~3). This non-protein like behaviour clearly indicates that it is the carbohydrate component which mainly influences the physical behaviour of the glycoconjugate in solution. PMID:26915577

  4. Nucleic acids, proteins, and chirality

    NASA Technical Reports Server (NTRS)

    Usher, D. A.; Profy, A. T.; Walstrum, S. A.; Needels, M. C.; Bulack, S. C.; Lo, K. M.

    1984-01-01

    The present investigation is concerned with experimental results related, in one case, to the chirality of nucleotides, and, in another case, to the possibility of a link between the chirality of nucleic acids, and that of peptides. It has been found that aminoacylation of the 'internal' hydroxyl group of a dinucleoside monophosphate can occur stereoselectively. However, this reaction has not yet been made a part of a working peptide synthesis scheme. The formation and cleavage of oligonucleotides is considered. In the event of the formation of a helical complex between the oligonucleotide and the polymer, 1-prime,5-prime-bonds in the oligomer are found to become more resistant towards cleavage. The conditions required for peptide bond formation are examined, taking into account the known structures of RNA and possible mechanisms for prebiotic peptide bond formation. The possibility is considered that the 2-prime,5-prime-internucleotide linkage could have played an important part in the early days of biological peptide synthesis.

  5. Effect of the Ratio of Non-fibrous Carbohydrates to Neutral Detergent Fiber and Protein Structure on Intake, Digestibility, Rumen Fermentation, and Nitrogen Metabolism in Lambs

    PubMed Central

    Ma, T.; Tu, Y.; Zhang, N. F.; Deng, K. D.; Diao, Q. Y.

    2015-01-01

    This study aimed to investigate the effect of the ratio of non-fibrous carbohydrates to neutral detergent fibre (NFC/NDF) and undegraded dietary protein (UDP) on rumen fermentation and nitrogen metabolism in lambs. Four Dorper×thin-tailed Han crossbred lambs, averaging 62.3±1.9 kg of body weight and 10 mo of age, were randomly assigned to four dietary treatments of combinations of two levels of NFC/NDF (1.0 and 1.7) and two levels of UDP (35% and 50% of crude protein [CP]). Duodenal nutrient flows were measured with dual markers of Yb and Co, and microbial N (MN) synthesis was estimated using 15N. High UDP decreased organic matter (OM) intake (p = 0.002) and CP intake (p = 0.005). Ruminal pH (p<0.001), ammonia nitrogen (NH3-N; p = 0.008), and total volatile fatty acids (p<0.001) were affected by dietary NFC/NDF. The ruminal concentration of NH3-N was also affected by UDP (p<0.001). The duodenal flow of total MN (p = 0.007) was greater for lambs fed the high NFC/NDF diet. The amount of metabolisable N increased with increasing dietary NFC:NDF (p = 0.02) or UDP (p = 0.04). In conclusion, the diets with high NFC/NDF (1.7) and UDP (50% of CP) improved metabolisable N supply to lambs. PMID:26323398

  6. Substitution of crude cell wall for neutral detergent fibre in the equations of the Cornell Net Carbohydrate and Protein System that predict carbohydrate fractions: application to sunflower ( Helianthus annuus L.).

    PubMed

    Queiroz, M A A; Fukushima, R S; Gomide, C A; Braga, M R

    2008-07-01

    Prediction of carbohydrate fractions using equations from the Cornell Net Carbohydrate and Protein System (CNCPS) is a valuable tool to assess the nutritional value of forages. In this paper, these carbohydrate fractions were predicted using data from three sunflower (Helianthus annuus L.) cultivars, fresh or as silage. The CNCPS equations for fractions B2 and C include measurement of ash and protein-free neutral detergent fibre (NDF) as one of their components. However, NDF lacks pectin and other non-starch polysaccharides that are found in the cell wall (CW) matrix, so this work compared the use of a crude CW preparation instead of NDF in the CNCPS equations. There were no differences in the estimates of fractions B1 and C when CW replaced NDF; however, there were differences in fractions A and B2. Some of the CNCPS equations could be simplified when using CW instead of NDF. Notably, lignin could be expressed as a proportion of DM, rather than on the basis of ash and protein-free NDF, when predicting CNCPS fraction C. The CNCPS fraction B1 (starch + pectin) values were lower than pectin determined through wet chemistry. This finding, along with the results obtained by the substitution of CW for NDF in the CNCPS equations, suggests that pectin was not part of fraction B1 but present in fraction A. We suggest that pectin and other non-starch polysaccharides that are dissolved by the neutral detergent solution be allocated to a specific fraction (B2) and that another fraction (B3) be adopted for the digestible cell wall carbohydrates.

  7. Evaluation of endogenous acidic metabolic products associated with carbohydrate metabolism in tumor cells

    PubMed Central

    Mazzio, Elizabeth A.; Smith, Bruce

    2010-01-01

    Tumor cells have a high tolerance for acidic and hypoxic microenvironments, also producing abundant lactic acid through accelerated glycolysis in the presence or absence of O2. While the accumulation of lactate is thought to be a major contributor to the reduction of pH-circumscribing aggressive tumors, it is not known if other endogenous metabolic products contribute this acidity. Furthermore, anaerobic metabolism in cancer cells bears similarity to homo-fermentative lactic acid bacteria, however very little is known about an alternative pathway that may drive adenosine triphosphate (ATP) production independent of glycolysis. In this study, we quantify over 40 end-products (amines, acids, alcohols, aldehydes, or ketones) produced by malignant neuroblastoma under accelerated glycolysis (+glucose (GLU) supply 1–10 mM) ± mitochondrial toxin; 1-methyl-4-phenyl-pyridinium (MPP+) to abate aerobic respiration to delineate differences between anaerobic vs. aerobic cell required metabolic pathways. The data show that an acceleration of anaerobic glycolysis prompts an expected reduction in extracellular pH (pHex) from neutral to 6.7±0.006. Diverse metabolic acids associated with this drop in acidity were quantified by ionic exchange liquid chromatography (LC), showing concomitant rise in lactate (Ctrls 7.5±0.5 mM; +GLU 12.35±1.3 mM; +GLU + MPP 18.1±1.8 mM), acetate (Ctrl 0.84±0.13 mM: +GLU 1.3±0.15 mM; +GLU + MPP 2.7±0.4 mM), fumarate, and a-ketoglutarate (<10μM) while a range of other metabolic organic acids remained undetected. Amino acids quantified by o-phthalaldehyde precolumn derivatization/electrochemical detection–LC show accumulation of L-alanine (1.6±.052 mM), L-glutamate (285±9.7μM), L-asparagine (202±2.1μM), and L-aspartate (84.2±4.9μM) produced during routine metabolism, while other amino acids remain undetected. In contrast, the data show no evidence for accumulation of acetaldehyde, aldehydes, or ketones (Purpald/2

  8. Carbohydrate-Based Nanocarriers Exhibiting Specific Cell Targeting with Minimum Influence from the Protein Corona.

    PubMed

    Kang, Biao; Okwieka, Patricia; Schöttler, Susanne; Winzen, Svenja; Langhanki, Jens; Mohr, Kristin; Opatz, Till; Mailänder, Volker; Landfester, Katharina; Wurm, Frederik R

    2015-06-15

    Whenever nanoparticles encounter biological fluids like blood, proteins adsorb on their surface and form a so-called protein corona. Although its importance is widely accepted, information on the influence of surface functionalization of nanocarriers on the protein corona is still sparse, especially concerning how the functionalization of PEGylated nanocarriers with targeting agents will affect protein corona formation and how the protein corona may in turn influence the targeting effect. Herein, hydroxyethyl starch nanocarriers (HES-NCs) were prepared, PEGylated, and modified on the outer PEG layer with mannose to target dendritic cells (DCs). Their interaction with human plasma was then studied. Low overall protein adsorption with a distinct protein pattern and high specific affinity for DC binding were observed, thus indicating an efficient combination of "stealth" and targeting behavior.

  9. Amino acid and carbohydrate tradeoffs by honey bee nectar foragers and their implications for plant-pollinator interactions.

    PubMed

    Hendriksma, Harmen P; Oxman, Karmi L; Shafir, Sharoni

    2014-10-01

    Honey bees are important pollinators, requiring floral pollen and nectar for nutrition. Nectar is rich in sugars, but contains additional nutrients, including amino acids (AAs). We tested the preferences of free-flying foragers between 20 AAs at 0.1% w/w in sucrose solutions in an artificial meadow. We found consistent preferences amongst AAs, with essential AAs preferred over nonessential AAs. The preference of foragers correlated negatively with AA induced deviations in pH values, as compared to the control. Next, we quantified tradeoffs between attractive and deterrent AAs at the expense of carbohydrates in nectar. Bees were attracted by phenylalanine, willing to give up 84units sucrose for 1unit AA. They were deterred by glycine, and adding 100 or more units of sucrose could resolve to offset 1unit AA. In addition, we tested physiological effects of AA nutrition on forager homing performance. In a no-choice context, caged bees showed indifference to 0.1% proline, leucine, glycine or phenylalanine in sucrose solutions. Furthermore, flight tests gave no indication that AA nutrition affected flight capacity directly. In contrast, low carbohydrate nutrition reduced the performance of bees, with important methodological implications for homing studies that evaluate the effect of substances that may affect imbibition of sugar solution. In conclusion, low AA concentrations in nectar relative to pollen suggest a limited role in bee nutrition. Most of the 20 AAs evoked a neutral to a mild deterrent response in bees, thus it seems unlikely that bees respond to AAs in nectar as a cue to assess nutritional quality. Nonetheless, free choice behavior of foraging bees is influenced, for instance by phenylalanine and glycine. Thus, AAs in nectar may affect plant-pollinator interactions and thereby exhibit a selective pressure on the flora in the honey bee habitat.

  10. Amino acid and carbohydrate tradeoffs by honey bee nectar foragers and their implications for plant-pollinator interactions.

    PubMed

    Hendriksma, Harmen P; Oxman, Karmi L; Shafir, Sharoni

    2014-10-01

    Honey bees are important pollinators, requiring floral pollen and nectar for nutrition. Nectar is rich in sugars, but contains additional nutrients, including amino acids (AAs). We tested the preferences of free-flying foragers between 20 AAs at 0.1% w/w in sucrose solutions in an artificial meadow. We found consistent preferences amongst AAs, with essential AAs preferred over nonessential AAs. The preference of foragers correlated negatively with AA induced deviations in pH values, as compared to the control. Next, we quantified tradeoffs between attractive and deterrent AAs at the expense of carbohydrates in nectar. Bees were attracted by phenylalanine, willing to give up 84units sucrose for 1unit AA. They were deterred by glycine, and adding 100 or more units of sucrose could resolve to offset 1unit AA. In addition, we tested physiological effects of AA nutrition on forager homing performance. In a no-choice context, caged bees showed indifference to 0.1% proline, leucine, glycine or phenylalanine in sucrose solutions. Furthermore, flight tests gave no indication that AA nutrition affected flight capacity directly. In contrast, low carbohydrate nutrition reduced the performance of bees, with important methodological implications for homing studies that evaluate the effect of substances that may affect imbibition of sugar solution. In conclusion, low AA concentrations in nectar relative to pollen suggest a limited role in bee nutrition. Most of the 20 AAs evoked a neutral to a mild deterrent response in bees, thus it seems unlikely that bees respond to AAs in nectar as a cue to assess nutritional quality. Nonetheless, free choice behavior of foraging bees is influenced, for instance by phenylalanine and glycine. Thus, AAs in nectar may affect plant-pollinator interactions and thereby exhibit a selective pressure on the flora in the honey bee habitat. PMID:24952325

  11. Production of levulinic acid, furfural, and gamma valerolactone from C.sub.5 and C.sub.6 carbohydrates in mono- and biphasic systems using gamma-valerolactone as a solvent

    DOEpatents

    Dumesic, James A.; Alonso, David Martin; Gurbuz, Elif I.; Wettstein, Stephanie G.

    2013-03-19

    A method to make levulinic acid (LA), furfural, or gamma-valerolactone (GVL). React cellulose (and/or other C.sub.6 carbohydrates) or xylose (and/or other C.sub.5 carbohydrates) or combinations thereof in a monophasic reaction medium comprising GVL and an acid; or (ii) a biphasic reaction system comprising an organic layer comprising GVL, and a substantially immiscible aqueous layer. At least a portion of the cellulose (and/or other C.sub.6 carbohydrates), if present, is converted to LA and at least a portion of the xylose (and/or other C.sub.5 carbohydrates), if present, is converted into furfural.

  12. The lipopolysaccharide-binding protein participating in hemocyte nodule formation in the silkworm Bombyx mori is a novel member of the C-type lectin superfamily with two different tandem carbohydrate-recognition domains.

    PubMed

    Koizumi, N; Imamura, M; Kadotani, T; Yaoi, K; Iwahana, H; Sato, R

    1999-01-25

    We recently isolated and characterized the lipopolysaccharide (LPS)-binding protein, BmLBP, from the larval hemolymph of the silkworm Bombyx mori. BmLBP is a pattern recognition molecule that recognizes the lipid A portion of LPS and participates in a cellular defense reaction. This paper describes the cDNA cloning of BmLBP. The deduced amino acid sequence of BmLBP revealed that BmLBP is a novel member of the C-type lectin superfamily with a unique structural feature that consists of two different carbohydrate-recognition domains in tandem, a short and a long form. PMID:9989592

  13. Implication of fermentable carbohydrates targeting the gut microbiota on conjugated linoleic acid production in high-fat-fed mice.

    PubMed

    Druart, Céline; Neyrinck, Audrey M; Dewulf, Evelyne M; De Backer, Fabienne C; Possemiers, Sam; Van de Wiele, Tom; Moens, Frédéric; De Vuyst, Luc; Cani, Patrice D; Larondelle, Yvan; Delzenne, Nathalie M

    2013-09-28

    In vitro experiments have shown that isolated human gut bacteria are able to metabolise PUFA into conjugated PUFA like conjugated linoleic acids (CLA). The hypothesis of the present paper was that high-fat (HF) diet feeding and supplementation with fermentable carbohydrates that have prebiotic properties modulate the in vivo production of CLA by the mouse gut microbiota. Mice were treated for 4 weeks as follows: control (CT) groups were fed a standard diet; HF groups were fed a HF diet rich in linoleic acid (18 : 2n-6); the third groups were fed with the HF diet supplemented with either inulin-type fructans (HF-ITF) or arabinoxylans (HF-Ax). HF diet feeding increased rumenic acid (cis-9,trans-11-18 : 2 CLA) content both in the caecal and liver tissues compared with the CT groups. ITF supplementation had no major effect compared with the HF diet whereas Ax supplementation increased further rumenic acid (cis-9,trans-11-18 : 2 CLA) in the caecal tissue. These differences between both prebiotics may be linked to the high fat-binding capacity of Ax that provides more substrates for bacterial metabolism and to differential modulation of the gut microbiota (specific increase in Roseburia spp. in HF-Ax v. HF). In conclusion, these experiments supply the proof of concept that the mouse gut microbiota produces CLA in vivo, with consequences on the level of CLA in the caecal and liver tissues. We postulate that the CLA-producing bacteria could be a mediator to consider in the metabolic effects of both HF diet feeding and prebiotic supplementation.

  14. Carbohydrate Analysis

    NASA Astrophysics Data System (ADS)

    Bemiller, James N.

    Carbohydrates are important in foods as a major source of energy, to impart crucial textural properties, and as dietary fiber which influences physiological processes. Digestible carbohydrates, which are converted into monosaccharides, which are absorbed, provide metabolic energy. Worldwide, carbohydrates account for more than 70% of the caloric value of the human diet. It is recommended that all persons should limit calories from fat (the other significant source) to not more than 30% and that most of the carbohydrate calories should come from starch. Nondigestible polysaccharides (all those other than starch) comprise the major portion of dietary fiber (Sect. 10.5). Carbohydrates also contribute other attributes, including bulk, body, viscosity, stability to emulsions and foams, water-holding capacity, freeze-thaw stability, browning, flavors, aromas, and a range of desirable textures (from crispness to smooth, soft gels). They also provide satiety. Basic carbohydrate structures, chemistry, and terminology can be found in references (1, 2).

  15. Acid Functionalized Mesoporous Ordered Materials for the Production of 5-Hydroxymethyfurfural from Carbohydrates

    NASA Astrophysics Data System (ADS)

    Crisci, Anthony J.

    Solid acid catalysts were designed for the conversion of fructose to 5-hydroxymethylfurfural (HMF). Some of the catalysts incorporate thioether groups to promote the tautomerization of fructose to its furanose form, as well as sulfonic acid groups to catalyze its dehydration. A bifunctional silane, 3-((3-(trimethoxysilyl)propyl)thio)propane-1-sulfonic acid (TESAS), was designed for incorporation into SBA-15-type silica by co-condensation. To achieve mesopore ordering in the functionalized silica, the standard SBA-15 synthetic protocol was modified, resulting in well-formed hexagonal particles. Functional groups incorporated into mesoporous silica by co-condensation are more robust under the reaction conditions than those grafted onto a non-porous silica. In a variation, the thioether group of TESAS was oxidized by H2O 2 to the sulfone during the synthesis of the modified SBA-15. The materials were tested in batch reactors and compared in the selective dehydration of fructose to 5-hydroxymethylfurfural (HMF). Compared to benchmark catalysts, the thioether-containing TESAS-SBA-15 showed the highest activity in the dehydration of aqueous fructose, as well as the highest selectivity towards HMF (71 % at 84 % conversion). In addition, the stability of several supported acid catalysts was evaluated in tubular reactors designed to produce 5-hydroxymethylfurfural (HMF) continuously. The reactors, packed with the solid catalysts, were operated at 403 K for extended periods, up to 180 h. The behaviors of three propylsulfonic acid-functionalized, ordered porous silicas (one inorganic SBA-15-type silica, and two ethane-bridged SBA-15-type organosilicas) were compared with that of a propylsulfonic acid-modified, non-ordered porous silica. The HMF selectivity of the catalysts with ordered pore structures ranged from 60 to 75 %, while the selectivity of the non-ordered catalyst peaked at 20 %. The latter was also the least stable, deactivating with a first-order rate constant of

  16. KM+, a mannose-binding lectin from Artocarpus integrifolia: amino acid sequence, predicted tertiary structure, carbohydrate recognition, and analysis of the beta-prism fold.

    PubMed

    Rosa, J C; De Oliveira, P S; Garratt, R; Beltramini, L; Resing, K; Roque-Barreira, M C; Greene, L J

    1999-01-01

    The complete amino acid sequence of the lectin KM+ from Artocarpus integrifolia (jackfruit), which contains 149 residues/mol, is reported and compared to those of other members of the Moraceae family, particularly that of jacalin, also from jackfruit, with which it shares 52% sequence identity. KM+ presents an acetyl-blocked N-terminus and is not posttranslationally modified by proteolytic cleavage as is the case for jacalin. Rather, it possesses a short, glycine-rich linker that unites the regions homologous to the alpha- and beta-chains of jacalin. The results of homology modeling implicate the linker sequence in sterically impeding rotation of the side chain of Asp141 within the binding site pocket. As a consequence, the aspartic acid is locked into a conformation adequate only for the recognition of equatorial hydroxyl groups on the C4 epimeric center (alpha-D-mannose, alpha-D-glucose, and their derivatives). In contrast, the internal cleavage of the jacalin chain permits free rotation of the homologous aspartic acid, rendering it capable of accepting hydrogen bonds from both possible hydroxyl configurations on C4. We suggest that, together with direct recognition of epimeric hydroxyls and the steric exclusion of disfavored ligands, conformational restriction of the lectin should be considered to be a new mechanism by which selectivity may be built into carbohydrate binding sites. Jacalin and KM+ adopt the beta-prism fold already observed in two unrelated protein families. Despite presenting little or no sequence similarity, an analysis of the beta-prism reveals a canonical feature repeatedly present in all such structures, which is based on six largely hydrophobic residues within a beta-hairpin containing two classic-type beta-bulges. We suggest the term beta-prism motif to describe this feature.

  17. Alimentary proteins, amino acids and cholesterolemia.

    PubMed

    Blachier, François; Lancha, Antonio H; Boutry, Claire; Tomé, Daniel

    2010-01-01

    Numerous data from both epidemiological and experimental origins indicate that some alimentary proteins and amino acids in supplements can modify the blood LDL cholesterol, HDL cholesterol and total cholesterol. After an initial approval of the health claim for soy protein consumption for the prevention of coronary heart disease, more recently it has been concluded from an overall analysis of literature that isolated soy protein with isoflavones only slightly decrease LDL and total cholesterol. Other plant extracts and also some proteins from animal origin have been reported to exert a lowering effect on blood cholesterol when compared with a reference protein (often casein). The underlying mechanisms are still little understood. Individual amino acids and mixture of amino acids have also been tested (mostly in animal studies) for their effects on cholesterol parameters and on cholesterol metabolism. Methionine, lysine, cystine, leucine, aspartate and glutamate have been tested individually and in combination in different models of either normo or hypercholesterolemic animals and found to be able to modify blood cholesterol and/or LDL cholesterol and/or HDL cholesterol. It is however not known if these results are relevant to human nutrition.

  18. An amino acid-electrolyte beverage may increase cellular rehydration relative to carbohydrate-electrolyte and flavored water beverages

    PubMed Central

    2014-01-01

    Background In cases of dehydration exceeding a 2% loss of body weight, athletic performance can be significantly compromised. Carbohydrate and/or electrolyte containing beverages have been effective for rehydration and recovery of performance, yet amino acid containing beverages remain unexamined. Therefore, the purpose of this study is to compare the rehydration capabilities of an electrolyte-carbohydrate (EC), electrolyte-branched chain amino acid (EA), and flavored water (FW) beverages. Methods Twenty men (n = 10; 26.7 ± 4.8 years; 174.3 ± 6.4 cm; 74.2 ± 10.9 kg) and women (n = 10; 27.1 ± 4.7 years; 175.3 ± 7.9 cm; 71.0 ± 6.5 kg) participated in this crossover study. For each trial, subjects were dehydrated, provided one of three random beverages, and monitored for the following three hours. Measurements were collected prior to and immediately after dehydration and 4 hours after dehydration (3 hours after rehydration) (AE = −2.5 ± 0.55%; CE = −2.2 ± 0.43%; FW = −2.5 ± 0.62%). Measurements collected at each time point were urine volume, urine specific gravity, drink volume, and fluid retention. Results No significant differences (p > 0.05) existed between beverages for urine volume, drink volume, or fluid retention for any time-point. Treatment x time interactions existed for urine specific gravity (USG) (p < 0.05). Post hoc analysis revealed differences occurred between the FW and EA beverages (p = 0.003) and between the EC and EA beverages (p = 0.007) at 4 hours after rehydration. Wherein, EA USG returned to baseline at 4 hours post-dehydration (mean difference from pre to 4 hours post-dehydration = -0.0002; p > 0.05) while both EC (-0.0067) and FW (-0.0051) continued to produce dilute urine and failed to return to baseline at the same time-point (p < 0.05). Conclusion Because no differences existed for fluid retention, urine or drink volume at any time point, yet USG returned to

  19. Adipose tissue transcriptional response of lipid metabolism genes in growing Iberian pigs fed oleic acid v. carbohydrate enriched diets.

    PubMed

    Benítez, R; Núñez, Y; Fernández, A; Isabel, B; Rodríguez, C; Daza, A; López-Bote, C; Silió, L; Óvilo, C

    2016-06-01

    Diet influences animal body and tissue composition due to direct deposition and to the nutrients effects on metabolism. The influence of specific nutrients on the molecular regulation of lipogenesis is not well characterized and is known to be influenced by many factors including timing and physiological status. A trial was performed to study the effects of different dietary energy sources on lipogenic genes transcription in ham adipose tissue of Iberian pigs, at different growth periods and on feeding/fasting situations. A total of 27 Iberian male pigs of 28 kg BW were allocated to two separate groups and fed with different isocaloric feeding regimens: standard diet with carbohydrates as energy source (CH) or diet enriched with high oleic sunflower oil (HO). Ham subcutaneous adipose tissue was sampled by biopsy at growing (44 kg mean BW) and finishing (100 kg mean BW) periods. The first sampling was performed on fasted animals, while the last sampling was performed twice, with animals fasted overnight and 3 h after refeeding. Effects of diet, growth period and feeding/fasting status on gene expression were explored quantifying the expression of a panel of key genes implicated in lipogenesis and lipid metabolism processes. Quantitative PCR revealed several differentially expressed genes according to diet, with similar results at both timings: RXRG, LEP and FABP5 genes were upregulated in HO group while ME1, FASN, ACACA and ELOVL6 were upregulated in CH. The diet effect on ME1 gene expression was conditional on feeding/fasting status, with the higher ME1 gene expression in CH than HO groups, observed only in fasting samples. Results are compatible with a higher de novo endogenous synthesis of fatty acids (FA) in the carbohydrate-supplemented group and a higher FA transport in the oleic acid-supplemented group. Growth period significantly affected the expression of most of the studied genes, with all but PPARG showing higher expression in finishing pigs according to

  20. A comprehensive study on energy absorption and exposure buildup factors for some essential amino acids, fatty acids and carbohydrates in the energy range 0.015-15 MeV up to 40 mean free path

    NASA Astrophysics Data System (ADS)

    Kurudirek, Murat; Özdemir, Yüksel

    2011-01-01

    The gamma ray energy absorption ( EABF) and exposure buildup factors ( EBF) have been calculated for some essential amino acids, fatty acids and carbohydrates in the energy region 0.015-15 MeV up to a penetration depth of 40 mfp (mean free path). The five parameter geometric progression (G-P) fitting approximation has been used to calculate both EABF and EBF. Variations of EABF and EBF with incident photon energy, penetration depth and weight fraction of elements have been studied. While the significant variations in EABF and EBF for amino acids and fatty acids have been observed at the intermediate energy region where Compton scattering is the main photon interaction process, the values of EABF and EBF appear to be almost the same for all carbohydrates in the continuous energy region. It has been observed that the fatty acids have the largest EABF and EBF at 0.08 and 0.1 MeV, respectively, whereas the maximum values of EABF and EBF have been observed for aminoacids and carbohydrates at 0.1 MeV. At the fixed energy of 1.5 MeV, the variation of EABF with penetration depth appears to be independent of the variations in chemical composition of the amino acids, fatty acids and carbohydrates. Significant variations were also observed between EABF and EBF which may be due to the variations in chemical composition of the given materials.

  1. Exploring the interactions between bacteriophage-encoded glycan binding proteins and carbohydrates.

    PubMed

    Simpson, David J; Sacher, Jessica C; Szymanski, Christine M

    2015-10-01

    There is an unprecedented interest in glycobiology due to the increasing appreciation of its impact on all aspects of life. Likewise, bacteriophage biology is enjoying a new renaissance as the post-antibiotic era fuels the search for novel ways to control harmful bacteria. Phages have spent the last 3 billion years developing ways of recognizing and manipulating bacterial surface glycans. Therefore, phages comprise a massive reservoir of glycan-binding and -hydrolyzing proteins with the potential to be exploited for glycan analysis, bacterial diagnostics and therapeutics. We discuss phage tail proteins that recognize bacterial surface polysaccharides, endolysins that bind and cleave peptidoglycan, Ig-like proteins that attach to mucin glycans, and phage effector proteins that recognize both bacterial and eukaryotic oligosaccharides.

  2. Intake of Meals Containing High Levels of Carbohydrates or High Levels of Unsaturated Fatty Acids Induces Postprandial Dysmetabolism in Young Overweight/Obese Men

    PubMed Central

    Adamska, Edyta; Ostrowska, Lucyna; Gościk, Joanna; Waszczeniuk, Magdalena; Krętowski, Adam; Górska, Maria

    2015-01-01

    Postprandial metabolic response depends on the meals' components and can be different in normal weight and obese people. However, there are some discrepancies between various reports. The aim of this study was to determine the metabolic response after intake of standardised meals with various fat and carbohydrate contents and to determine the differences among normal weight and overweight/obese individuals. The study group comprised 46 healthy men. The participants were divided into two groups and study was carried out using a crossover method. Group I received high- and normal-carbohydrate meals, whereas group II received high-carbohydrate and high-fat meals. Glucose, insulin, triglyceride, and free fatty acids levels were measured at fasting state and at 30, 60, 120, 180, and 240 minutes after meal intake. Despite the lack of differences in glucose levels, insulin levels were higher among overweight/obese individuals after each meal. TG and FFA levels were higher after normal-carbohydrate and high-fat meals. Moreover, in overweight/obese young men after high-fat meal intake postprandial hypertriglyceridemia was observed, even if meals contained predominantly unsaturated fatty acids, and fasting triglycerides levels were in normal range. The conducted study showed that postprandial metabolic response depends not only on the meal macronutrient content but also on the current body mass index (BMI). PMID:26609520

  3. Carbohydrate and Amino Acid Metabolism in the Ectomycorrhizal Ascomycete Sphaerosporella brunnea during Glucose Utilization 1

    PubMed Central

    Martin, Francis; Ramstedt, Mauritz; Söderhäll, Kenneth; Canet, Daniel

    1988-01-01

    Nuclear magnetic resonance spectroscopy was utilized to study the metabolism of [1-13C]glucose in mycelia of the ectomycorrhizal ascomycete Sphaerosporella brunnea. The main purpose was to assess the biochemical pathways for the assimilation of glucose and to identify the compounds accumulated during glucose assimilation. The majority of the 13C label was incorporated into mannitol, while glycogen, trehalose and free amino acids were labeled to a much lesser extent. The high enrichment of the C1/C6 position of mannitol indicated that the polyol was formed via a direct route from absorbed glucose. Randomization of the 13C label was observed to occur in glucose and trehalose leading to the accumulation of [1,6-13C]trehalose and [1,6-13C]glucose. This suggests that the majority of the glucose carbon used to form trehalose was cycled through the metabolically active mannitol pool. The proportion of label entering the free amino acids represented 38% of the soluble 13C after 6 hours of continuous glucose labeling. Therefore, amino acid biosynthesis is an important sink of assimilated carbon. Carbon-13 was incorporated into [3-13C]alanine and [2-13C]-, [3-13C]-, and [4-13C]glutamate and glutamine. From the analysis of the intramolecular 13C enrichment of these amino acids, it is concluded that [3-13C]pyruvate, arising from [1-13C]glucose catabolism, was used by alanine aminotransferase, pyruvate dehydrogenase, and pyruvate carboxylase (or phosphoenolpyruvate carboxykinase). Intramolecular 13C labeling patterns of glutamate and glutamine were similar and are consistent with the operation of the Krebs cycle. There is strong evidence for (a) randomization of the label on C2 and C3 positions of oxaloacetate via malate dehydrogenase and fumarase, and (b) the dual biosynthetic and respiratory role of the citrate synthase, aconitase, and isocitrate dehydrogenase reactions. The high flux of carbon through the carboxylation (presumably pyruvate carboxylase) step indicates that CO

  4. Protein and Amino Acid Requirements during Pregnancy.

    PubMed

    Elango, Rajavel; Ball, Ronald O

    2016-07-01

    Protein forms an essential component of a healthy diet in humans to support both growth and maintenance. During pregnancy, an exceptional stage of life defined by rapid growth and development, adequate dietary protein is crucial to ensure a healthy outcome. Protein deposition in maternal and fetal tissues increases throughout pregnancy, with most occurring during the third trimester. Dietary protein intake recommendations are based on factorial estimates because the traditional method of determining protein requirements, nitrogen balance, is invasive and undesirable during pregnancy. The current Estimated Average Requirement and RDA recommendations of 0.88 and 1.1 g · kg(-1) · d(-1), respectively, are for all stages of pregnancy. The single recommendation does not take into account the changing needs during different stages of pregnancy. Recently, with the use of the minimally invasive indicator amino acid oxidation method, we defined the requirements to be, on average, 1.2 and 1.52 g · kg(-1) · d(-1) during early (∼16 wk) and late (∼36 wk) stages of pregnancy, respectively. Although the requirements are substantially higher than current recommendations, our values are ∼14-18% of total energy and fit within the Acceptable Macronutrient Distribution Range. Using swine as an animal model we showed that the requirements for several indispensable amino acids increase dramatically during late gestation compared with early gestation. Additional studies should be conducted during pregnancy to confirm the newly determined protein requirements and to determine the indispensable amino acid requirements during pregnancy in humans. PMID:27422521

  5. Kinetics and mechanism of permanganate oxidation of iota- and lambda-carrageenan polysaccharides as sulfated carbohydrates in acid perchlorate solutions.

    PubMed

    Hassan, Refat M; Fawzy, Ahmed; Ahmed, Gamal A; Zaafarany, Ishaq A; Asghar, Basim H; Takagi, Hideo D; Ikeda, Yasuhisa

    2011-10-18

    The kinetics of oxidation of iota- and lambda-carrageenan as sulfated carbohydrates by permanganate ion in aqueous perchlorate solutions at a constant ionic strength of 2.0 mol dm(-3) have been investigated spectrophotometrically. The pseudo-first-order plots were found to be of inverted S-shape throughout the entire courses of reactions. The initial rates were found to be relatively slow in the early stages, followed by an increase in the oxidation rates over longer time periods. The experimental observations showed first-order dependences in permanganate and fractional first-order kinetics with respect to both carrageenans concentration for both the induction and autoacceleration periods. The results obtained at various hydrogen ion concentrations showed that the oxidation processes in these redox systems are acid-catalyzed throughout the two stages of oxidation reactions. The added salts lead to the prediction that Mn(III) is the reactive species throughout the autoacceleration periods. Kinetic evidence for the formation of 1:1 intermediate complexes was revealed. The kinetic parameters have been evaluated and tentative reaction mechanisms in good agreement with the kinetic results are discussed.

  6. Effects of dietary levels of carbohydrate, lipid, phosphorus and zinc on the growth, feed conversion and protein efficiency ratio of Nile tilapia ( Oreochromis niloticus)

    NASA Astrophysics Data System (ADS)

    Li, Zhongjie; Lei, Wu; Yang, Yunxia; Ye, Jun

    1993-09-01

    A 54-day feeding experiment was conducted on juvenile Nile tilapia using isonitrogenous, isocaloric semipurified diets. The carbohydrate content in the diet was 9%, 32% and 50%; the corresponding lipid content was 22.2%, 12%, and 4%. The diets were supplemented with 0.85% or 1.5% phosphorus and 40 mg/kg or 100 mg/kg zinc. The experiment was carried out in flow-through aquaria using dechlorinated tap water at 23 26°C. The experiment showed that the increase of the carbohydrate content in the diets resulted in a 43 249% increase in weight gain, a 27 59% decrease in feed conversion ratio, and a 65 121% increase in protein efficiency ratio. In fish fed diets containing 36 50% carbohydrate, an increase in supplemented phosphorus to 1.5% greatly increased the weight gain. On the contrary, a high content of supplemented zinc (100 mg/kg) inhibited growth and increased feed conversion ratio.

  7. Chemical Reporter for Visualizing Metabolic Cross-Talk between Carbohydrate Metabolism and Protein Modification

    PubMed Central

    2015-01-01

    Metabolic chemical reporters have been largely used to study posttranslational modifications. Generally, it was assumed that these reporters entered one biosynthetic pathway, resulting in labeling of one type of modification. However, because they are metabolized by cells before their addition onto proteins, metabolic chemical reporters potentially provide a unique opportunity to read-out on both modifications of interest and cellular metabolism. We report here the development of a metabolic chemical reporter 1-deoxy-N-pentynyl glucosamine (1-deoxy-GlcNAlk). This small-molecule cannot be incorporated into glycans; however, treatment of mammalian cells results in labeling of a variety proteins and enables their visualization and identification. Competition of this labeling with sodium acetate and an acetyltransferase inhibitor suggests that 1-deoxy-GlcNAlk can enter the protein acetylation pathway. These results demonstrate that metabolic chemical reporters have the potential to isolate and potentially discover cross-talk between metabolic pathways in living cells. PMID:25062036

  8. Chemical reporter for visualizing metabolic cross-talk between carbohydrate metabolism and protein modification.

    PubMed

    Zaro, Balyn W; Chuh, Kelly N; Pratt, Matthew R

    2014-09-19

    Metabolic chemical reporters have been largely used to study posttranslational modifications. Generally, it was assumed that these reporters entered one biosynthetic pathway, resulting in labeling of one type of modification. However, because they are metabolized by cells before their addition onto proteins, metabolic chemical reporters potentially provide a unique opportunity to read-out on both modifications of interest and cellular metabolism. We report here the development of a metabolic chemical reporter 1-deoxy-N-pentynyl glucosamine (1-deoxy-GlcNAlk). This small-molecule cannot be incorporated into glycans; however, treatment of mammalian cells results in labeling of a variety proteins and enables their visualization and identification. Competition of this labeling with sodium acetate and an acetyltransferase inhibitor suggests that 1-deoxy-GlcNAlk can enter the protein acetylation pathway. These results demonstrate that metabolic chemical reporters have the potential to isolate and potentially discover cross-talk between metabolic pathways in living cells.

  9. Effect of low carbohydrate high protein (LCHP) diet on lipid metabolism, liver and kidney function in rats.

    PubMed

    Kostogrys, Renata B; Franczyk-Żarów, Magdalena; Maślak, Edyta; Topolska, Kinga

    2015-03-01

    The objective of this study was to compare effects of Western diet (WD) with low carbohydrate high protein (LCHP) diet on lipid metabolism, liver and kidney function in rats. Eighteen rats were randomly assigned to three experimental groups and fed for the next 2 months. The experimental diets were: Control (7% of soybean oil, 20% protein), WD (21% of butter, 20% protein), and LCHP (21% of butter and 52.4% protein) diet. The LCHP diet significantly decreased the body weight of the rats. Diet consumption was differentiated among groups, however significant changes were observed since third week of the experiment duration. Rats fed LCHP diet ate significantly less (25.2g/animal/day) than those from Control (30.2g/animal/day) and WD (27.8 g/animal/day) groups. Additionally, food efficiency ratio (FER) tended to decrease in LCHP fed rats. Serum homocysteine concentration significantly decreased in rats fed WD and LCHP diets. Liver weights were significantly higher in rats fed WD and LCHP diets. At the end of the experiment (2 months) the triacylglycerol (TAG) was significantly decreased in animals fed LCHP compared to WD. qRT-PCR showed that SCD-1 and FAS were decreased in LCHP fed rats, but WD diet increased expression of lipid metabolism genes. Rats receiving LCHP diet had two fold higher kidney weight and 54.5% higher creatinin level compared to Control and WD diets. In conclusion, LCHP diet decreased animal's body weight and decreased TAG in rat's serum. However, kidney damage in LCHP rats was observed. PMID:25766070

  10. Effect of low carbohydrate high protein (LCHP) diet on lipid metabolism, liver and kidney function in rats.

    PubMed

    Kostogrys, Renata B; Franczyk-Żarów, Magdalena; Maślak, Edyta; Topolska, Kinga

    2015-03-01

    The objective of this study was to compare effects of Western diet (WD) with low carbohydrate high protein (LCHP) diet on lipid metabolism, liver and kidney function in rats. Eighteen rats were randomly assigned to three experimental groups and fed for the next 2 months. The experimental diets were: Control (7% of soybean oil, 20% protein), WD (21% of butter, 20% protein), and LCHP (21% of butter and 52.4% protein) diet. The LCHP diet significantly decreased the body weight of the rats. Diet consumption was differentiated among groups, however significant changes were observed since third week of the experiment duration. Rats fed LCHP diet ate significantly less (25.2g/animal/day) than those from Control (30.2g/animal/day) and WD (27.8 g/animal/day) groups. Additionally, food efficiency ratio (FER) tended to decrease in LCHP fed rats. Serum homocysteine concentration significantly decreased in rats fed WD and LCHP diets. Liver weights were significantly higher in rats fed WD and LCHP diets. At the end of the experiment (2 months) the triacylglycerol (TAG) was significantly decreased in animals fed LCHP compared to WD. qRT-PCR showed that SCD-1 and FAS were decreased in LCHP fed rats, but WD diet increased expression of lipid metabolism genes. Rats receiving LCHP diet had two fold higher kidney weight and 54.5% higher creatinin level compared to Control and WD diets. In conclusion, LCHP diet decreased animal's body weight and decreased TAG in rat's serum. However, kidney damage in LCHP rats was observed.

  11. Differential adhesion, activity, and carbohydrate: Protein ratios ofPseudomonas atlantica monocultures attaching to stainless steel in a linear shear gradient.

    PubMed

    Mittelman, M W; Nivens, D E; Low, C; White, D C

    1990-05-01

    Biofilm formation on metallic surfaces in marine and freshwater environments often precedes corrosion and other biofouling conditions. Attachment is mediated by such environmental factors as the presence of surface conditioning films, fluid dynamics, bulk-phase nutrient levels, and surface chemistry. In this study, we utilized a Fowler Cell Adhesion Measurement Module to demonstrate that the changes in cellular concentration and composition of a monoculture ofPseudomonas atlantica biofilms on stainless steel were a function of the applied shear force. At shear forces in the range of 3-10 dynes cm(-2) (1.0 liter min(-1)), attachment as measured by acridine orange direct microscopic counts was greatest at the higher shear forces.(14)C-Acetate uptake activity on the stainless steel surfaces increased with shear stress. Acetate incorporation ranged from 1×10(-5) to 19×10(-5) μmol cm(-2) between 0.15 and 30 dynes cm(-2) for 30 min uptake periods. On a per cell basis, however, activity decreased with shear, indicating a shift in metabolism. Fourier transform infrared spectroscopy revealed that protein and carbohydrate concentrations also increased with the applied shear. Increased biofilm C∶N ratios and total fatty acids were associated with the higher shear stresses. Neither radius of interaction nor biofilm age appeared to significantly influence the relationship between fluid shear and attachment and cellular composition ofP. atlantica biofilms in the range of 1-10 dynes cm(-2). PMID:24196364

  12. Pasting and extrusion properties of mixed carbohydrates and whey protein isolate matrices

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Mixed systems of whey protein isolate (WPI) or texturized WPI (tWPI) and different starches may form weak or strong gel pastes or rigid matrices depending on interactions. The paste viscoelasticity of starches from amioca, barley, corn starch, Hylon VII, plantain, and pea starch, mixed with whey pro...

  13. Effects of branched-chain amino acids and carbohydrate on fatigue during intermittent, high-intensity running.

    PubMed

    Davis, J M; Welsh, R S; De Volve, K L; Alderson, N A

    1999-07-01

    Experimental support for the hypothesized benefits of BCAA supplements on endurance performance is limited. However, it is theorized that the benefits may be enhanced if 1) BCAA are taken along with a pre-event carbohydrate meal as well as during exercise, and 2) the exercise is intermittent in nature. This study tested the effects of ingesting carbohydrate beverages with and without BCAA before and during intermittent high-intensity running to fatigue. Eight subjects performed 3 exercise trials consisting of intermittent shuttle running (walking, sprinting, and running) to fatigue. Subjects drank either carbohydrate drinks given 1 h before (5 mL/kg, 18% carbohydrate) and during exercise (2 mL/kg, 6% carbohydrate) (CHO), carbohydrate drinks with BCAA (7 g) added to the portions consumed 1 h before and immediately before exercise (CHO+BCAA), or flavored water placebos (P). Subjects ran longer when fed either CHO or CHO+BCAA as compared to P, with no differences between CHO and CHO+BCAA. CHO and CHO+BCAA also had higher plasma glucose and insulin, and lower FFA (p < 0.05). These findings confirm a beneficial effect of carbohydrate feedings on fatigue during exercise designed to mimic the activity pattern that occurs in sports like soccer, basketball, and hockey. They do not, however, support the hypothesis of an added benefit of BCAA supplements.

  14. Effects of dietary nonstructural carbohydrates and protein sources on feeding behavior of tethered heifers fed high-concentrate diets.

    PubMed

    Rotger, A; Ferret, A; Manteca, X; Ruiz de la Torre, J L; Calsamiglia, S

    2006-05-01

    To describe the feeding behavior of growing heifers fed high-concentrate diets with different sources of protein and nonstructural carbohydrates, and to explain the ruminal fermentation pattern, 4 ruminally fistulated Holstein heifers (BW = 132.3 +/- 1.61 kg) were assigned to a 4 x 4 Latin square design with a 2 x 2 factorial arrangement of treatments. Two non-structural carbohydrate sources (barley and corn) and 2 protein sources [soybean meal (SBM) and sunflower meal (SFM)] that differ in their rate and extent of ruminal degradation were combined, resulting in a synchronized, rapid fermentation diet (barley-SFM), a synchronized, slow fermentation diet (corn-SBM), and 2 unsynchronized diets consisting of a rapidly and a slowly fermenting component (barley-SBM and corn-SFM). The corn-SFM diet resulted in a lower frequency of feeding (P < or = 0.05), longer meal length (P < or = 0.043), and larger meal size (P < or = 0.037) than the other 3 diets. Dietary treatment had no effect (P > or = 0.09) on the daily percentages of posture and behaviors. In general, heifers spent 9.97 +/- 0.83% of the day eating, 2.11 +/- 0.42% drinking, 25.13 +/- 1.36% ruminating, 16.97 +/- 1.42% in other activities such as social behavior and self-grooming, and the rest of the day (45.82 +/- 2.55%) resting or doing no chewing activities. Eating, drinking, and social behaviors were performed while standing (P < or = 0.01), whereas resting and ruminating occurred mainly while lying (P = 0.001). Eating took place mainly in the first 4 h after feeding (P = 0.001), whereas ruminating occurred mainly at night (P = 0.001). When chewing activities (eating and ruminating) were expressed per kilogram of DM or NDF from roughage intake, more time (P = 0.004) was spent chewing per kilogram of DMI for barley-based diets, and per kilogram of NDF from roughage intake for barley- (P = 0.01) and SFM- (P = 0.002) based diets. Tethered heifers fed the more fermentable and rapidly synchronized diet (barley

  15. Carbohydrates on Proteins: Site-Specific Glycosylation Analysis by Mass Spectrometry

    NASA Astrophysics Data System (ADS)

    Zhu, Zhikai; Desaire, Heather

    2015-07-01

    Glycosylation on proteins adds complexity and versatility to these biologically vital macromolecules. To unveil the structure-function relationship of glycoproteins, glycopeptide-centric analysis using mass spectrometry (MS) has become a method of choice because the glycan is preserved on the glycosylation site and site-specific glycosylation profiles of proteins can be readily determined. However, glycopeptide analysis is still challenging given that glycopeptides are usually low in abundance and relatively difficult to detect and the resulting data require expertise to analyze. Viewing the urgent need to address these challenges, emerging methods and techniques are being developed with the goal of analyzing glycopeptides in a sensitive, comprehensive, and high-throughput manner. In this review, we discuss recent advances in glycoprotein and glycopeptide analysis, with topics covering sample preparation, analytical separation, MS and tandem MS techniques, as well as data interpretation and automation.

  16. Surface functionalization of liposomes with proteins and carbohydrates for use in anti-cancer applications

    NASA Astrophysics Data System (ADS)

    Platt, Virginia M.

    Liposomes can be used to exploit the altered biology of cancer thereby increasing delivery of liposome-associated anti-cancer drugs. In this dissertation, I explore methods that utilize the unique cancer expression of the polymeric glycosaminoglycan hyaluronan (HA) and the HA receptor CD44 to target liposomes to tumors, using liposomes functionalized with proteins or oligosaccharides on their surface. To make it easier to prepare protein-functionalized liposomes, a non-covalent protein/liposome association method based upon metal chelation/his 6 interaction was devised and characterized. I evaluated non-covalent attachment of the prodrug converting enzyme yeast cytosine deaminase, the far-red fluorescent protein mKate, two antigens ovalbumin and the membrane proximal region of an HIV GAG and hyaluronidase, a HA-degrading enzyme. In Chapter 2, I describe the synthesis of hyaluronan-oligosaccharide (HA-O) lipid conjugates and their incorporation into liposomes to target CD44-overexpressing cancer cells. HA-O ligands of defined-length, up to 10 monosaccharides, were attached to lipids via various linkers by reductive amination. The HA-lipids were easily incorporated into liposomes but did not mediate binding of liposomes to CD44 overexpressing cells. In Chapter 3, I evaluate the capacity of tris-NTA-Ni-lipids incorporated within a liposome bilayer to associate with his6-tagged proteins. Tris-NTA-lipids of differing structures and avidities were used to associate yeast cytosine deaminase and mKate to the surface of liposomes. Two tris-NTA-lipids and a mono-NTA lipid associated his-tagged proteins to a 1:1 molar ratio in solution. The proteins remained active while associated with the liposome surface. When challenged in vitro with fetal calf serum, tris-NTA-containing liposomes retained his-tagged proteins longer than mono-NTA. However, the tris-NTA/his6 interaction was found to be in a dynamic state; free yeast cytosine deaminase rapidly competed with pre-bound m

  17. Conversion of carbohydrate biomass to γ-valerolactone by using water-soluble and reusable iridium complexes in acidic aqueous media.

    PubMed

    Deng, Jin; Wang, Yan; Pan, Tao; Xu, Qing; Guo, Qing-Xiang; Fu, Yao

    2013-07-01

    Mild-mannered manipulation: A catalytic method for the conversion of carbohydrate biomass to γ-valerolactone in acidic aqueous media has been developed. The water-soluble iridium complexes were observed to be extremely catalytically active for providing γ-valerolactone in high yields with high TONs. The homogeneous catalysts can also be recycled and reused by applying a simple phase separation process. PMID:23757330

  18. Amino Acid Recycling in Relation to Protein Turnover 1

    PubMed Central

    Davies, David D.; Humphrey, Thomas J.

    1978-01-01

    Methods of measuring amino acid recycling in Lemna minor are described. The extent to which the recycling of individual amino acids may underestimate protein turnover has been measured for a number of amino acids. The methods have been used to study the relationship between protein turnover and amino acid recycling during nitrogen starvation. It is concluded that following the removal of nitrate from the environment, protein turnover is enhanced, the partitioning of amino acids between protein synthesis and amino acid metabolism is relatively constant, but the total amount of amino acids recycling is increased. PMID:16660236

  19. Negative effect of a low-carbohydrate, high-protein, high-fat diet on small peripheral artery reactivity in patients with increased cardiovascular risk.

    PubMed

    Merino, Jordi; Kones, Richard; Ferré, Raimon; Plana, Núria; Girona, Josefa; Aragonés, Gemma; Ibarretxe, Daiana; Heras, Mercedes; Masana, Luis

    2013-04-14

    Low-carbohydrate diets have become increasingly popular for weight loss. Although they may improve some metabolic markers, particularly in type 2 diabetes mellitus (T2D) or the metabolic syndrome (MS), their net effect on arterial wall function remains unclear. The objective was to evaluate the relation between dietary macronutrient composition and the small artery reactive hyperaemia index (saRHI), a marker of small artery endothelial function, in a cohort of patients at increased cardiovascular (CV) risk. The present cross-sectional study included 247 patients. Diet was evaluated by a 3-d food-intake register and reduced to a novel low-carbohydrate diet score (LCDS). Physical examination, demographic, biochemical and anthropometry parameters were recorded, and the saRHI was measured in each patient. Individuals in the lowest LCDS quartile (Q1, 45 % carbohydrate; 20 % protein; 32 % fat) had higher saRHI values than those in the top quartile (Q4, 29 % carbohydrate, 24 % protein, 40 % fat; 1.66 (sd 0.41) v. 1.52 (sd 0.22), P= 0.037). These results were particularly strong in patients with the MS (Q1 = 1.82 (sd 0.32) v. Q4 = 1.61 (sd 027); P= 0.021) and T2D (Q1 = 1.78 (sd 0.31) v. Q4 = 1.62 (sd 0.35); P= 0.011). Multivariate analysis demonstrated that individuals in the highest LCDS quartile had a significantly negative coefficient of saRHI, which was independent of confounders (OR -0.85; 95 % CI 0.19, 0.92; P= 0.031). These findings suggest that a dietary pattern characterised by a low amount of carbohydrate, but high amounts of protein and fat, is associated with a poorer small artery vascular reactivity in patients with increased CV risk.

  20. [Carbohydrates in clinical nutrition].

    PubMed

    Lysikov, Iu A

    2013-01-01

    The article presents data on role of carbohydrate in clinical nutrition. The review described carbohydrate metabolism, hormonal regulation of carbohydrate, carbohydrate energy source role, carbohydrate requirements in critical study.

  1. Microbial Degradation of Whole-Grain Complex Carbohydrates and Impact on Short-Chain Fatty Acids and Health1234

    PubMed Central

    Bach Knudsen, Knud Erik

    2015-01-01

    Whole-grain cereals have a complex dietary fiber (DF) composition consisting of oligosaccharides (mostly fructans), resistant starch, and nonstarch polysaccharides (NSPs); the most important are arabinoxylans, mixed-linkage β(1,3; 1,4)-d-glucan (β-glucan), and cellulose and the noncarbohydrate polyphenolic ether lignin. The highest concentration of NSPs and lignin is found in the outer cell layers of the grain, and refined flour will consequently be depleted of a large proportion of insoluble DF components. The flow and composition of carbohydrates to the large intestine are directly related to the intake of DF. The type and composition of cereal DF can consequently be used to modulate the microbial composition and activity as well as the production and molar ratios of short-chain fatty acids (SCFAs). Arabinoxylans and β-glucan in whole-grain cereals and cereal ingredients have been shown to augment SCFA production, with the strongest relative effect on butyrate. When arabinoxylans were provided as a concentrate, the effect was only on total SCFA production. Increased SCFA production in the large intestine was shown by the concentration in the portal vein, whereas the impact on the concentration in peripheral blood was less because the majority of propionate and butyrate is cleared in the liver. Active microbial fermentation with increased SCFA production reduced the exposure of potentially toxic compounds to the epithelium, potentially stimulating anorectic hormones and acting as signaling molecules between the gut and the peripheral tissues. The latter can have implications for insulin sensitivity and glucose homeostasis. PMID:25770259

  2. Non-adiabatic tapered optical fiber sensor for measuring the interaction between α-amino acids in aqueous carbohydrate solution

    NASA Astrophysics Data System (ADS)

    Zibaii, M. I.; Latifi, H.; Karami, M.; Gholami, M.; Hosseini, S. M.; Ghezelayagh, M. H.

    2010-10-01

    A single-mode non-adiabatic tapered optical fiber (NATOF) sensor was utilized for sensing the variation in refractive index (RI) with concentration of d-glucose in deionized water and measurement of the RI of amino acids (AAs) in carbohydrate solutions. This method showed a rewarding ability in understanding the basis of biomolecular interactions in biological systems. Due to high sensitivity, ease of application, low cost and real-time measurement, this method is more efficient in comparison with other techniques, such as calorimetric titration, NMR, UV absorption spectroscopy, x-ray crystallography, computer calculations, kinetic studies and chromatography data. The NATOF is fabricated by the heat pulling method, utilizing a CO2 laser. The limit of detection of the NATOF was 55 ppm for a d-glucose concentration ranging from 0 to 80 mg ml-1, and the limit of detection of the RI measurement corresponding to these concentrations in the range from 1.3330 to 1.3447 was 8.2 × 10-6 as a refractometer sensor. The response of the NATOF shows that different kinds of interactions of various groups of AAs, such as l-alanine, l-leucine and l-cysteine with d-glucose, sucrose and water molecules, depend on functional groups in AAs such as OH, SH, CH2, NH+3 and COO-. These results can be interpreted in terms of solute-solute and solute-solvent interactions and the structure making/breaking ability of solutes in the given solution. Such a study helps in the better understanding of the interactions occurring between AA molecules and entities present in biological matrices.

  3. High carbohydrate and high monounsaturated fatty acid diets similarly affect LDL electrophoretic characteristics in men who are losing weight.

    PubMed

    Archer, W Roodly; Lamarche, Benoît; St-Pierre, Annie C; Mauger, Jean-François; Dériaz, Olivier; Landry, Nancy; Corneau, Louise; Després, Jean-Pierre; Bergeron, Jean; Couture, Patrick; Bergeron, Nathalie

    2003-10-01

    We compared the effects of ad libitum consumption of a defined high complex carbohydrate (CHO) diet (% of energy: CHO, 58.3; fat, 25.8) vs. a defined high monounsaturated fatty acid (MUFA) diet (% of energy: CHO, 44.7; fat, 40.1; MUFA, 22.5) on LDL electrophoretic characteristics. Healthy men [n = 65; age, 37.5 +/- 11.2 (mean +/- SD) y; BMI, 29.2 +/- 4.9 kg/m2] were randomly assigned to one of the two diets that they consumed for 6-7 wk. The high CHO diet significantly reduced body weight (-2%). The diet-induced reduction in plasma LDL cholesterol (C) levels in the high-CHO diet group was due mainly to concurrent reductions in the cholesterol content of small (<25.5 nm, P < 0.01) and medium-sized LDL (25.5-26.0 nm, P = 0.01). The high MUFA diet also reduced body weight, and LDL-C and LDL-apolipoprotein (apo)B levels, which were comparable to those in the high CHO group. The cholesterol levels of small LDL particles tended to be reduced (P = 0.24) in the high MUFA group (-12%), similar to changes in the high CHO group. These results suggest that, when associated with weight loss, ad libitum consumption of high CHO and high MUFA diets may be considered to be equally beneficial for the management of LDL-related atherogenic dyslipidemia. However, the high MUFA diet more favorably affected triglyceride levels, suggesting that it may be preferable to a high CHO diet in cardiovascular disease prevention.

  4. Body composition, dietary carbohydrates and fatty acids determine post-fertilisation development of bovine oocytes in vitro.

    PubMed

    Adamiak, S J; Powell, K; Rooke, J A; Webb, R; Sinclair, K D

    2006-02-01

    This study assessed the interactive effects of carbohydrate type (fibre vs starch) and fatty acid (FA) supplementation (0% vs 6% calcium soaps of palm oil FA) on the post-fertilisation development of oocytes recovered from low and moderate body condition score (BCS) heifers. A secondary objective was to compare the FA composition of plasma to that of granulosa cells (GCs) and cumulus-oocyte complexes (COCs) from these animals, and to relate these findings to the developmental potential of oocytes. Plasma, GCs and COCs were recovered from 32 heifers on day 5 of a synchronised oestrous cycle for FA analyses. Oocytes were also recovered on days 10 and 15 of the same cycle after short-term ovarian stimulation (FSH + GnRH), and matured, fertilised and cultured to the blastocyst stage in vitro. High levels of dietary starch increased (P < 0.01) plasma insulin but, together with dietary FA, reduced (P < 0.05) blastocyst yields in low, but not in moderate, BCS heifers. Diet-induced alterations to the FA content of plasma were less apparent in GCs and COCs. In summary, although dietary lipids increased the FA content of COCs, the selective uptake of saturated FAs at the expense of mainly polyunsaturated FAs within the follicular compartment ensured that the FA composition of COCs was largely unaffected by diet. However, the concentration of saturated FAs within COCs was inherently high, and so further increases in FA content may have impaired post-fertilisation development. The data establish a robust nutritional framework for more detailed studies into the mechanistic effects of dietary composition on the post-fertilisation developmental potential of oocytes. PMID:16452718

  5. Microbial degradation of whole-grain complex carbohydrates and impact on short-chain fatty acids and health.

    PubMed

    Bach Knudsen, Knud Erik

    2015-03-01

    Whole-grain cereals have a complex dietary fiber (DF) composition consisting of oligosaccharides (mostly fructans), resistant starch, and nonstarch polysaccharides (NSPs); the most important are arabinoxylans, mixed-linkage β(1,3; 1,4)-d-glucan (β-glucan), and cellulose and the noncarbohydrate polyphenolic ether lignin. The highest concentration of NSPs and lignin is found in the outer cell layers of the grain, and refined flour will consequently be depleted of a large proportion of insoluble DF components. The flow and composition of carbohydrates to the large intestine are directly related to the intake of DF. The type and composition of cereal DF can consequently be used to modulate the microbial composition and activity as well as the production and molar ratios of short-chain fatty acids (SCFAs). Arabinoxylans and β-glucan in whole-grain cereals and cereal ingredients have been shown to augment SCFA production, with the strongest relative effect on butyrate. When arabinoxylans were provided as a concentrate, the effect was only on total SCFA production. Increased SCFA production in the large intestine was shown by the concentration in the portal vein, whereas the impact on the concentration in peripheral blood was less because the majority of propionate and butyrate is cleared in the liver. Active microbial fermentation with increased SCFA production reduced the exposure of potentially toxic compounds to the epithelium, potentially stimulating anorectic hormones and acting as signaling molecules between the gut and the peripheral tissues. The latter can have implications for insulin sensitivity and glucose homeostasis.

  6. Effects of clomazone herbicide on hematological and some parameters of protein and carbohydrate metabolism of silver catfish Rhamdia quelen.

    PubMed

    Crestani, Márcia; Menezes, Charlene; Glusczak, Lissandra; Dos Santos Miron, Denise; Lazzari, Rafael; Duarte, Marta F; Morsch, Vera Maria; Pippi, Amy Lee; Vieira, Vânia Pimentel

    2006-09-01

    The effects of clomazone (0.5 and 1.0 mg/L) according to nominal concentrations used in paddy rice fields (0.4-0.7 mg/L) on protein and carbohydrate metabolism and haematological parameters were evaluated in silver catfish (Rhamdia quelen) after 12, 24, 48, 96 and 192 h of exposure with a recovery period of 96 and 192 h. Liver glycogen increased significantly (P<0.05) in all periods and concentrations tested. The maximum glycogen increase reaches 250% after 12h of exposure. Muscle glycogen reduced significantly after 24, 48, 96 and 192 h for both clomazone concentrations (P<0.05). Significantly elevated plasma glucose values (P<0.05) and variation in glucose in the liver and muscle of exposed fish were observed. Muscle lactate levels increased after 12, 24 and 48 h of clomazone exposure (22-67%), but reduced in the liver (P<0.05). Protein levels were enhanced in the liver and white muscle, except at 96 and 192 h of exposure, whereas it increased in the plasma in the period from 48 to 96 h (P<0.05). Alanine aminotransferase (ALT) and aspartate aminotransferase (AST) activities were significantly elevated in the plasma (P<0.05). In the liver, ALT increased after 24 h, while AST activity was enhanced only after 12 h of exposure. Hematocrit contents were reduced after 96 and 192 h of exposure. Most of the metabolic disorders observed did not persist after the recovery period, except for the liver AST and ALT activity. Clomazone concentrations used in this study appear safe to fish, Rhamdia quelen, because overall parameters can be recovered after 96 and 192 h in clean water. ALT and AST activity may be an early biomarker of clomazone toxicity.

  7. Hypothalamic norepinephrine turnover response to a single low protein, high carbohydrate meal in the male Wistar rat

    SciTech Connect

    Raum, W.; Glick, Z.

    1986-03-01

    A single meal stimulates norepinephrine turnover (NET) by approximately 4-fold in the brown adipose tissue (BAT). In this experiment the role of the hypothalamus in regulating this response was examined. NET was measured in the cortex (C), ventro-medial (VMH), and the lateral hypothalamus (LH). A total of 48 male Wistar rats (200 g body weight) were trained to eat during two feeding sessions per day. On the experimental day, one group (N = 24) was meal deprived and the other (N = 24) was given a low protein, high carbohydrate test meal for 2 hours. NET was determined by the synthesis inhibition method using alpha-methyltyrosine (AMT) injected within one hour after the meal. Norepinephrine (NE) content in each brain section was measured by radioimmunoassay at 4 time points (0, 1, 2, 3 hours) after AMT. The turnover rate (TR) was calculated as the slope of the decline in NE content over time (ng/mg protein/hr) following AMT. The fraction of the total pool of NE released/hr (k) was calculated by dividing the slope (TR) by the Y intercept (NE content at zero time). NET (TR) increased significantly (p < .05) in the VMH following a meal (9.36 +/- .67 vs 8.04 +/- .98 ng/hr; fed vs deprived). There was no change in TR in the C or LH, or in k in any brain section. The marked (4-fold) increase in BAT NET and minimal increase in VMH NET suggests that the meal has a direct effect on BAT with the VMH playing a secondary or modulatory role.

  8. Production of high optical purity l-lactic acid from waste activated sludge by supplementing carbohydrate: effect of temperature and pretreatment time.

    PubMed

    Jian, Qiwei; Li, Xiang; Chen, Yinguang; Liu, Yanan; Pan, Yin

    2016-10-01

    It has been widely accepted that the most environmentally beneficial way to treat waste activated sludge (WAS), the byproduct of municipal wastewater treatment plant, is to recover the valuable organic acid. However, the bio-conversion of lactic acid, one of the high added-value chemical, is seldom reported from WAS fermentation. In this paper, l-lactic acid was observed dominant in the WAS fermentation liquid with carbohydrate addition at ambient temperature. Furthermore, the effect of temperature on l-lactic acid and d-lactic acid production was fully discussed: two isomers were rapidly produced and consumed up in one day at mesophilic condition; and almost optically pure l-lactic acid was generated at thermophilic condition, yet time-consuming with yield of l-lactic acid enhancing by 52.9% compared to that at ambient temperature. The study mechanism showed that mesophilic condition was optimal for both production and consumption of l-lactic acid and d-lactic acid, while consumption of l-lactic acid and production of d-lactic acid were severely inhibited at thermophilic condition. Therefore, by maintaining thermophilic for 4 h in advance and subsequently fermenting mesophilic for 34 h, the concentration of l-lactic acid with optical activity of 98.3% was improved to 16.6 ± 0.5 g COD/L at a high specific efficiency of 0.6097/d.

  9. Versatile acetylation of carbohydrate substrates with bench-top sulfonic acids and application to one-pot syntheses of peracetylated thioglycosides.

    PubMed

    Chao, Chin-Sheng; Chen, Min-Chun; Lin, Shih-Che; Mong, Kwok-Kong T

    2008-04-01

    Inexpensive and readily available sulfonic acids, p-toluenesulfonic acid, and sulfuric acid are versatile and efficient catalysts for the peracetylation of a broad spectrum of carbohydrate substrates in good yield and in a practical time frame. Three appealing features in sulfonic acid-catalyzed acetylation of free sugars were explored including (1) suppression of furanosyl acetate formation for D-galactose and L-fucose; (2) high yielding chemoselective acetylation of sialic acid under appropriate conditions; and (3) peracetylation of amino sugars with different amino protecting functions. Simple one-pot two step acetylation-thioglycosidation methods for the expeditious synthesis of p-tolyl per-O-acetyl thioglycosides were also delineated.

  10. Protein and Amino Acid Profiles of Different Whey Protein Supplements.

    PubMed

    Almeida, Cristine C; Alvares, Thiago S; Costa, Marion P; Conte-Junior, Carlos A

    2016-01-01

    Whey protein (WP) supplements have received increasing attention by consumers due to the high nutritional value of the proteins and amino acids they provide. However, some WP supplements may not contain the disclosed amounts of the ingredients listed on the label, compromising the nutritional quality and the effectiveness of these supplements. The aim of this study was to evaluate and compare the contents of total protein (TP), α-lactalbumin (α-LA), β-lactoglobulin (β-LG), free essential amino acids (free EAA), and free branched-chain amino acids (free BCAA), amongst different WP supplements produced by U.S. and Brazilian companies. Twenty commercial brands of WP supplements were selected, ten manufactured in U.S. (WP-USA) and ten in Brazil (WP-BRA). The TP was analyzed using the Kjeldahl method, while α-LA, β-LG, free EAA, and free BCAA were analyzed using HPLC system. There were higher (p < 0.05) concentrations of TP, α-LA, β-LG, and free BCAA in WP-USA supplements, as compared to the WP-BRA supplements; however, there was no difference (p > 0.05) in the content of free EAA between WP-USA and WP-BRA. Amongst the 20 brands evaluated, four WP-USA and seven WP-BRA had lower (p < 0.05) values of TP than those specified on the label. In conclusion, the WP-USA supplements exhibited better nutritional quality, evaluated by TP, α-LA, β-LG, and free BCAA when compared to WP-BRA.

  11. Effects of recombinant human growth hormone therapy on carbohydrate, lipid and protein metabolisms of children with Turner syndrome

    PubMed Central

    Qi, Weibin; Li, Shuxian; Shen, Qiong; Guo, Xiuxia; Rong, Huijuan

    2014-01-01

    Objective: To study the effect of recombinant human growth hormone (rhGH) therapy on carbohydrate, lipid and protein metabolisms of Turner syndrome (TS). Metho d s: Total 45 patients with TS admitted between Jul. 2008 and Jun. 2011 were involved in this study. All patients received the clinical evaluation of body fat, plasma lipids, proteins and oral glucose tolerance test (OGTT) before and after rhGH therapy. Results : Our results indicated a significant decrease of body fat (FAT%) from 23.56±4.21 to 18.71±2.23 but no obvious change on the level of fat mass (FM) (p>0.05) was observed after rhGH therapy. We also detected significant changes on plasma high-density lipoprotein cholesterol (HDL-C) from (1.65±0.58 mmol/L) to (2.20±0.65 mmol/L) and low-density lipoprotein cholesterol (LDH-C) from (2.55±0.55 mmol/L) to (2.10±0.54 mmol/L) after rhGH exposure. However, no statistical significance was detected on the level of plasma triglyceride (TG), cholesterol (CHO). Interestingly, the levels of plasma retinol binding protein (RbP) (32.55±4.28mg/L), transferrin (TRF) (2.95±0.40 mg/L), serum albumin (PRE) (250.00±45.50 mg/L) and albumin (propagated) (33.58±4.25 mg/L) were significantly increased. When it goes to the oral glucose tolerance test (OGTT) test, there were 10 impaired glucose tolerance (IGT) cases among all patients before and after rhGH therapy. No significant change was observed on homeostasis model assessment- insulin resistance (HOMA-IR) level during rhGH intervention. Conclusion : Abnormal lipid and protein metabolisms of the children with TS can be improved with rhGH therapy for 6 months. PMID:25097506

  12. The roles of carbohydrates, proteins and lipids in the process of aggregation of natural marine organic matter investigated by means of 2D correlation spectroscopy applied to infrared spectra

    NASA Astrophysics Data System (ADS)

    Mecozzi, Mauro; Pietrantonio, Eva; Pietroletti, Marco

    2009-01-01

    In this paper the marine organic matter soluble in an alkaline medium called extractable humic substance (EHS), was extracted from three sediment samples of Tyrrhenian Sea and separated by precipitation at pH 2 in the two fractions of fulvic acids (FAs) and humic acids (HAs). FAs were further fractionated in seven sub-samples of different molecular weight (mw) by means of seven different ultrafiltration membranes operating in the range between mw < 1 kDa and mw > 100 kDa. Then the qualitative composition of each sample of fractionated FAs and HAs was studied by means of one-dimensional Fourier transform infrared spectroscopy in reflectance mode (FTIR-DRIFT) and by two-dimensional (2D) correlation spectroscopy both in wavelength-wavelength (WW) and in sample-sample (SS) mode. The application of 2D correlation WW spectroscopy allows to elucidate the different roles played by carbohydrates and proteins with respect to some lipid compounds such as fatty acids and ester fatty acids during the process of aggregate formations from mw ˜1 kDa to higher size aggregates. In addition, 2D correlation WW spectroscopy allows to observe some peculiar interactions between carbohydrates and proteins in the formation of EHS aggregates, interactions which vary from a sample to another sample. The results of 2D correlation SS spectroscopy confirm the general evidences obtained by 2D WW spectroscopy and moreover, they also describe the formation of EHS aggregates as a complex process where evolutionary links and connectivity between aggregates of neighbour molecular size ranges are not evident. Two-dimensional correlation spectroscopy applied to FTIR spectroscopy shows to be a powerful tool for the investigation of the mechanisms involved in EHS aggregation because it supports the acquisition of structural information which sometimes can be hardly obtained by one-dimensional FTIR spectroscopy.

  13. Alterations in protein, carbohydrate, and fat metabolism in injured and septic patients.

    PubMed

    Wilmore, D W

    1983-01-01

    The physiological and biochemical responses of the body following major injury or severe infection are characterized by hypermetabolism, accelerated gluconeogenesis, and the mobilization of substrates from the carcass to be utilized by visceral organs. These responses in the febrile patient are supported by an elevated cardiac output which insures perfusion of vital organs and provides additional bloodflow to the area of inflammation and/or injury. Because of the accelerated substrate flux and increased catabolism, weight loss and negative nitrogen balance are profound. Cumulative losses rapidly approach near-lethal limits if adequate nutritional support is not instituted. Nutritional maintenance will support the febrile response, maintain body nitrogen and acute phase protein synthesis, and assure an ongoing energy supply. Reparative tissue appears to preferentially utilize substrate, but if malnutrition occurs, wound healing and tissue repair may be limited. The effects of nutritional support on immunological function in these critically ill patients are only now being dissected. Clearly, immunosuppression is related to the initial insult and abnormalities in host defense mechanisms occur almost immediately in patients well nourished before illness. In addition, nutrient depletion and erosion of body mass are also associated with immunological dysfunction so that these two factors combine to impair the patient's resistance to subsequent infection. Present therapy should maintain balance of essential nutrients while complications associated with specialized techniques of nutrient support are minimized. Control of the patient's environment, minimizing pain and discomfort, preventing "bad rest" effect through exercise are all techniques of supportive care, but responses are ablated with resolution of the infection or wound closure, and every effort should be directed toward this goal. PMID:6886243

  14. Confined housing system increased abdominal and subcutaneous fat deposition and gene expressions of carbohydrate response element-binding protein and sterol regulatory element-binding protein 1 in chicken.

    PubMed

    Li, Q; Zhao, X L; Gilbert, E R; Liu, Y P; Wang, Y; Qiu, M H; Zhu, Q

    2015-01-01

    Free-range production system is increasingly being used in poultry breeding and feed production in many countries. The objective of the current experiment was to evaluate the effects of different raising systems on fat-related traits and mRNA levels of liver lipogenesis genes in Erlang Mountainous chicken. Each of 10 birds (91 day old) from caged, indoor-floor housed, and free-range housing systems was slaughtered, and fat-related traits, live body weight (BW), subcutaneous fat thickness (SFT), abdominal fat weight (AFW), abdominal fat percentage (AFP), and intramuscular fat content were determined. The mRNA levels of liver X receptor α, carbohydrate response element-binding protein (ChREBP), sterol regulatory element-binding protein-1 (SREBP1), and fatty acid synthase were detected. The caged chicken exhibited significantly higher BW, SFT, and AFW than those of free-ranged chicken (P < 0.05). All the 4 genes had a similar expression pattern, and they showed the highest level in caged chicken, while the lowest level was found in free-ranged chicken. Association analysis indicated that there were significant (P < 0.05) or highly significant (P < 0.01) positive correlations between the mRNA levels of ChREBP, SREBP1, and fat traits of SFT, AFW, and AFP. Thus, we deduced that increased fat deposition in caged chicken was probably induced by increased gene expression of ChREBP and SREBP1 in the liver. PMID:25730060

  15. Confined housing system increased abdominal and subcutaneous fat deposition and gene expressions of carbohydrate response element-binding protein and sterol regulatory element-binding protein 1 in chicken.

    PubMed

    Li, Q; Zhao, X L; Gilbert, E R; Liu, Y P; Wang, Y; Qiu, M H; Zhu, Q

    2015-02-06

    Free-range production system is increasingly being used in poultry breeding and feed production in many countries. The objective of the current experiment was to evaluate the effects of different raising systems on fat-related traits and mRNA levels of liver lipogenesis genes in Erlang Mountainous chicken. Each of 10 birds (91 day old) from caged, indoor-floor housed, and free-range housing systems was slaughtered, and fat-related traits, live body weight (BW), subcutaneous fat thickness (SFT), abdominal fat weight (AFW), abdominal fat percentage (AFP), and intramuscular fat content were determined. The mRNA levels of liver X receptor α, carbohydrate response element-binding protein (ChREBP), sterol regulatory element-binding protein-1 (SREBP1), and fatty acid synthase were detected. The caged chicken exhibited significantly higher BW, SFT, and AFW than those of free-ranged chicken (P < 0.05). All the 4 genes had a similar expression pattern, and they showed the highest level in caged chicken, while the lowest level was found in free-ranged chicken. Association analysis indicated that there were significant (P < 0.05) or highly significant (P < 0.01) positive correlations between the mRNA levels of ChREBP, SREBP1, and fat traits of SFT, AFW, and AFP. Thus, we deduced that increased fat deposition in caged chicken was probably induced by increased gene expression of ChREBP and SREBP1 in the liver.

  16. Content of short-chain fatty acids in the hindgut of rats fed processed bean (Phaseolus vulgaris) flours varying in distribution and content of indigestible carbohydrates.

    PubMed

    Henningsson, A M; Nyman, E M; Björck, I M

    2001-09-01

    Red kidney beans (Phaseolus vulgaris) processed to differ in distribution and content of indigestible carbohydrates were used to study hindgut fermentability and production of short-chain fatty acids (SCFA). Bean flours with low or high content of resistant starch (RS), mainly raw and physically-inaccessible starch, were obtained by milling the beans before or after boiling. Flours containing retrograded starch and with a high or low content of oligosaccharides were prepared by autoclaving followed by freeze-drying with or without the boiling water. Six diets were prepared from these flours yielding a total concentration of indigestible carbohydrates of 90 or 120 g/kg (dry weight basis). The total fermentability of the indigestible carbohydrates was high with all diets (80-87 %). Raw and physically-inaccessible starch was more readily fermented than retrograded starch (97-99 % v. 86-95 %; ). Non-starch glucans were fermented to a lesser extent than RS, but the fermentability was higher in the case of autoclaved (50-54 %) than boiled beans (37-41 %). The distribution between acetic, propionic and butyric acid in the caecum was similar for all diets, with a comparatively high percentage of butyric acid (approximately 18). However, with diets containing the high amounts of RS, the butyric acid concentration was significantly higher in the distal colon than in the proximal colon ( and for the high- and low-level diets respectively), whereas it remained constant, or decreased along the colon in the case of the other diets. Furthermore, the two diets richest in RS also promoted the highest percentages of butyric acid in the distal colon (24 and 17 v. 12 and 12-16 for the high- and low-level diets respectively). PMID:11570990

  17. Increase in the carbohydrate content of the microalgae Spirulina in culture by nutrient starvation and the addition of residues of whey protein concentrate.

    PubMed

    Vieira Salla, Ana Cláudia; Margarites, Ana Cláudia; Seibel, Fábio Ivan; Holz, Luiz Carlos; Brião, Vandré Barbosa; Bertolin, Telma Elita; Colla, Luciane Maria; Costa, Jorge Alberto Vieira

    2016-06-01

    Non-renewable sources that will end with time are the largest part of world energy consumption, which emphasizes the necessity to develop renewable sources of energy. This necessity has created opportunities for the use of microalgae as a biofuel. The use of microalgae as a feedstock source for bioethanol production requires high yields of both biomass and carbohydrates. With mixotrophic cultures, wastewater can be used to culture algae. The aim of the study was to increase the carbohydrate content in the microalgae Spirulina with the additions of residues from the ultra and nanofiltration of whey protein. The nutrient deficit in the Zarrouk medium diluted to 20% and the addition of 2.5% of both residue types led to high carbohydrate productivity (60 mg L(-1) d(-1)). With these culture conditions, the increase in carbohydrate production in Spirulina indicated that the conditions were appropriate for use with microalgae as a feedstock in the production of bioethanol. PMID:26967336

  18. Carbohydrates as a tool for oriented immobilization of antigens and antibodies.

    PubMed

    Turková, J; Petkov, L; Sajdok, J; Kás, J; Benes, M J

    1990-02-01

    A biospecific sorbent for the isolation of ovalbumin antibodies was prepared by coupling of ovalbumin via its periodate-oxidized carbohydrate moiety to bead cellulose modified with adipic acid dihydrazide. The anti-ovalbumin IgG fraction isolated on this sorbent from immune rabbit serum contained only antibodies against protein determinants of ovalbumin. Thus, when these IgG were immobilized through their carbohydrate moieties to cellulose beads it became possible to prepare a biospecific sorbent for concanavalin A by oriented adsorption of ovalbumin. Ovalbumin was specifically adsorbed via its protein moiety and its carbohydrate part remained free for interaction with concanavalin A. PMID:2329151

  19. Differential responses of the incretin hormones GIP and GLP-1 to increasing doses of dietary carbohydrate but not dietary protein in lean rats.

    PubMed

    Yoder, Stephanie M; Yang, Qing; Kindel, Tammy L; Tso, Patrick

    2010-08-01

    Previous studies have shown that oral ingestion of nutrients stimulates secretion of the incretin hormones glucose-dependent insulinotropic polypeptide (GIP) and glucagon-like peptide-1 (GLP-1); however, it is unclear whether there is a dose-dependent response between the amount of nutrient ingested and the secretion of the hormones in vivo. Using our lymph fistula rat model, we previously demonstrated that both GIP and GLP-1 responded dose dependently to increasing amounts of infused dietary lipid and that the GLP-1-secreting cells were more sensitive to changes in intestinal lipid content. In the present study, we investigated the dose-dependent relationships between incretin secretion and the two remaining macronutrients, carbohydrate and protein. To accomplish this objective, the major mesenteric lymphatic duct of male Sprague-Dawley rats was cannulated. Each animal received a single bolus (3 ml) of saline, dextrin, whey protein, or casein hydrolysate (0.275, 0.55, 1.1, 2.2, 4.4 kcal) via a surgically inserted duodenal or ileal feeding tube. Lymph was continuously collected for 3 h and analyzed for GIP and GLP-1 content. Both GIP and GLP-1 outputs responded dose dependently to increasing amounts of dietary carbohydrate but not protein. Additionally, we found that the GIP-secreting cells were more sensitive than the GLP-1-secreting cells to changes in intestinal carbohydrate content.

  20. Effects of a carbohydrate-, protein-, and ribose-containing repletion drink during 8 weeks of endurance training on aerobic capacity, endurance performance, and body composition.

    PubMed

    Cramer, Joel T; Housh, Terry J; Johnson, Glen O; Coburn, Jared W; Stout, Jeffrey R

    2012-08-01

    This study compared a carbohydrate-, protein-, and ribose-containing repletion drink vs. carbohydrates alone during 8 weeks of aerobic training. Thirty-two men (age, mean ± SD = 23 ± 3 years) performed tests for aerobic capacity (V(O2)peak), time to exhaustion (TTE) at 90% V(O2)peak, and percent body fat (%fat), and fat-free mass (FFM). Testing was conducted at pre-training (PRE), mid-training at 3 weeks (MID3), mid-training at 6 weeks (MID6), and post-training (POST). Cycle ergometry training was performed at 70% V(O2)peak for 1 hours per day, 5 days per week for 8 weeks. Participants were assigned to a test drink (TEST; 370 kcal, 76 g carbohydrate, 14 g protein, 2.2 g d-ribose; n = 15) or control drink (CON; 370 kcal, 93 g carbohydrate; n = 17) ingested immediately after training. Body weight (BW; 1.8% decrease CON; 1.3% decrease TEST from PRE to POST), %fat (5.5% decrease CON; 3.9% decrease TEST), and FFM (0.1% decrease CON; 0.6% decrease TEST) decreased (p ≤ 0.05), whereas V(O2)peak (19.1% increase CON; 15.8% increase TEST) and TTE (239.1% increase CON; 377.3% increase TEST) increased (p ≤ 0.05) throughout the 8 weeks of training. Percent decreases in %fat from PRE to MID3 and percent increases in FFM from PRE to MID3 and MID6 were greater (p ≤ 0.05) for TEST than CON. Overall, even though the TEST drink did not augment BW, V(O2)peak, or TTE beyond carbohydrates alone, it did improve body composition (%fat and FFM) within the first 3-6 weeks of supplementation, which may be helpful for practitioners to understand how carbohydrate-protein recovery drinks can and cannot improve performance in their athletes.

  1. Liver Fatty Acid Binding Protein and Obesity

    PubMed Central

    Atshaves, B.P.; Martin, G.G.; Hostetler, H.A.; McIntosh, A.L.; Kier, A.B.; Schroeder, F.

    2010-01-01

    While low levels of unesterified long chain fatty acids (LCFAs) are normal metabolic intermediates of dietary and endogenous fat, LCFAs are also potent regulators of key receptors/enzymes, and at high levels become toxic detergents within the cell. Elevated levels of LCFAs are associated with diabetes, obesity, and metabolic syndrome. Consequently, mammals evolved fatty acid binding proteins (FABPs) that bind/sequester these potentially toxic free fatty acids in the cytosol and present them for rapid removal in oxidative (mitochondria, peroxisomes) or storage (endoplasmic reticulum, lipid droplets) organelles. Mammals have a large (15 member) family of FABPs with multiple members occurring within a single cell type. The first described FABP, liver-FABP (L-FABP, or FABP1), is expressed in very high levels (2-5% of cytosolic protein) in liver as well as intestine and kidney. Since L-FABP facilitates uptake and metabolism of LCFAs in vitro and in cultured cells, it was expected that abnormal function or loss of L-FABP would reduce hepatic LCFA uptake/oxidation and thereby increase LCFAs available for oxidation in muscle and/or storage in adipose. This prediction was confirmed in vitro with isolated liver slices and cultured primary hepatocytes from L-FABP gene-ablated mice. Despite unaltered food consumption when fed a control diet ad libitum, the L-FABP null mice exhibited age- and sex-dependent weight gain and increased fat tissue mass. The obese phenotype was exacerbated in L-FABP null mice pair-fed a high fat diet. Taken together with other findings, these data suggest that L-FABP could have an important role in preventing age- or diet-induced obesity. PMID:20537520

  2. Sex-specific effects of protein and carbohydrate intake on reproduction but not lifespan in Drosophila melanogaster

    PubMed Central

    Jensen, Kim; McClure, Colin; Priest, Nicholas K; Hunt, John

    2015-01-01

    Modest dietary restriction extends lifespan (LS) in a diverse range of taxa and typically has a larger effect in females than males. Traditionally, this has been attributed to a stronger trade-off between LS and reproduction in females than in males that is mediated by the intake of calories. Recent studies, however, suggest that it is the intake of specific nutrients that extends LS and mediates this trade-off. Here, we used the geometric framework (GF) to examine the sex-specific effects of protein (P) and carbohydrate (C) intake on LS and reproduction in Drosophila melanogaster. We found that LS was maximized at a high intake of C and a low intake of P in both sexes, whereas nutrient intake had divergent effects on reproduction. Male offspring production rate and LS were maximized at the same intake of nutrients, whereas female egg production rate was maximized at a high intake of diets with a P:C ratio of 1:2. This resulted in larger differences in nutrient-dependent optima for LS and reproduction in females than in males, as well as an optimal intake of nutrients for lifetime reproduction that differed between the sexes. Under dietary choice, the sexes followed similar feeding trajectories regulated around a P:C ratio of 1:4. Consequently, neither sex reached their nutritional optimum for lifetime reproduction, suggesting intralocus sexual conflict over nutrient optimization. Our study shows clear sex differences in the nutritional requirements of reproduction in D. melanogaster and joins the growing list of studies challenging the role of caloric restriction in extending LS. PMID:25808180

  3. Sex-specific effects of protein and carbohydrate intake on reproduction but not lifespan in Drosophila melanogaster.

    PubMed

    Jensen, Kim; McClure, Colin; Priest, Nicholas K; Hunt, John

    2015-08-01

    Modest dietary restriction extends lifespan (LS) in a diverse range of taxa and typically has a larger effect in females than males. Traditionally, this has been attributed to a stronger trade-off between LS and reproduction in females than in males that is mediated by the intake of calories. Recent studies, however, suggest that it is the intake of specific nutrients that extends LS and mediates this trade-off. Here, we used the geometric framework (GF) to examine the sex-specific effects of protein (P) and carbohydrate (C) intake on LS and reproduction in Drosophila melanogaster. We found that LS was maximized at a high intake of C and a low intake of P in both sexes, whereas nutrient intake had divergent effects on reproduction. Male offspring production rate and LS were maximized at the same intake of nutrients, whereas female egg production rate was maximized at a high intake of diets with a P:C ratio of 1:2. This resulted in larger differences in nutrient-dependent optima for LS and reproduction in females than in males, as well as an optimal intake of nutrients for lifetime reproduction that differed between the sexes. Under dietary choice, the sexes followed similar feeding trajectories regulated around a P:C ratio of 1:4. Consequently, neither sex reached their nutritional optimum for lifetime reproduction, suggesting intralocus sexual conflict over nutrient optimization. Our study shows clear sex differences in the nutritional requirements of reproduction in D. melanogaster and joins the growing list of studies challenging the role of caloric restriction in extending LS.

  4. Co-Ingestion of Whey Protein with a Carbohydrate-Rich Breakfast Does Not Affect Glycemia, Insulinemia or Subjective Appetite Following a Subsequent Meal in Healthy Males

    PubMed Central

    Allerton, Dean M.; Campbell, Matthew D.; Gonzalez, Javier T.; Rumbold, Penny L. S.; West, Daniel J.; Stevenson, Emma J.

    2016-01-01

    We aimed to assess postprandial metabolic and appetite responses to a mixed-macronutrient lunch following prior addition of whey protein to a carbohydrate-rich breakfast. Ten healthy males (age: 24 ± 1 years; body mass index (BMI): 24.5 ± 0.7 kg/m2) completed three trials in a non-isocaloric, crossover design. A carbohydrate-rich breakfast (93 g carbohydrate; 1799 kJ) was consumed with (CHO + WP) or without (CHO) 20 g whey protein isolate (373 kJ), or breakfast was omitted (NB). At 180 min, participants consumed a mixed-macronutrient lunch meal. Venous blood was sampled at 15 min intervals following each meal and every 30 min thereafter, while subjective appetite sensations were collected every 30 min throughout. Post-breakfast insulinemia was greater after CHO + WP (time-averaged area under the curve (AUC0–180 min): 193.1 ± 26.3 pmol/L), compared to CHO (154.7 ± 18.5 pmol/L) and NB (46.1 ± 8.0 pmol/L; p < 0.05), with no difference in post-breakfast (0–180 min) glycemia (CHO + WP, 3.8 ± 0.2 mmol/L; CHO, 4.2 ± 0.2 mmol/L; NB, 4.2 ± 0.1 mmol/L; p = 0.247). There were no post-lunch (0–180 min) effects of condition on glycemia (p = 0.492), insulinemia (p = 0.338) or subjective appetite (p > 0.05). Adding whey protein to a carbohydrate-rich breakfast enhanced the acute postprandial insulin response, without influencing metabolic or appetite responses following a subsequent mixed-macronutrient meal. PMID:26927166

  5. Co-Ingestion of Whey Protein with a Carbohydrate-Rich Breakfast Does Not Affect Glycemia, Insulinemia or Subjective Appetite Following a Subsequent Meal in Healthy Males.

    PubMed

    Allerton, Dean M; Campbell, Matthew D; Gonzalez, Javier T; Rumbold, Penny L S; West, Daniel J; Stevenson, Emma J

    2016-03-01

    We aimed to assess postprandial metabolic and appetite responses to a mixed-macronutrient lunch following prior addition of whey protein to a carbohydrate-rich breakfast. Ten healthy males (age: 24 ± 1 years; body mass index (BMI): 24.5 ± 0.7 kg/m²) completed three trials in a non-isocaloric, crossover design. A carbohydrate-rich breakfast (93 g carbohydrate; 1799 kJ) was consumed with (CHO + WP) or without (CHO) 20 g whey protein isolate (373 kJ), or breakfast was omitted (NB). At 180 min, participants consumed a mixed-macronutrient lunch meal. Venous blood was sampled at 15 min intervals following each meal and every 30 min thereafter, while subjective appetite sensations were collected every 30 min throughout. Post-breakfast insulinemia was greater after CHO + WP (time-averaged area under the curve (AUC0--180 min): 193.1 ± 26.3 pmol/L), compared to CHO (154.7 ± 18.5 pmol/L) and NB (46.1 ± 8.0 pmol/L; p < 0.05), with no difference in post-breakfast (0-180 min) glycemia (CHO + WP, 3.8 ± 0.2 mmol/L; CHO, 4.2 ± 0.2 mmol/L; NB, 4.2 ± 0.1 mmol/L; p = 0.247). There were no post-lunch (0-180 min) effects of condition on glycemia (p = 0.492), insulinemia (p = 0.338) or subjective appetite (p > 0.05). Adding whey protein to a carbohydrate-rich breakfast enhanced the acute postprandial insulin response, without influencing metabolic or appetite responses following a subsequent mixed-macronutrient meal. PMID:26927166

  6. Nucleic acids encoding human trithorax protein

    DOEpatents

    Evans, Glen A.; Djabali, Malek; Selleri, Licia; Parry, Pauline

    2001-01-01

    In accordance with the present invention, there is provided an isolated peptide having the characteristics of human trithorax protein (as well as DNA encoding same, antisense DNA derived therefrom and antagonists therefor). The invention peptide is characterized by having a DNA binding domain comprising multiple zinc fingers and at least 40% amino acid identity with respect to the DNA binding domain of Drosophila trithorax protein and at least 70% conserved sequence with respect to the DNA binding domain of Drosophila trithorax protein, and wherein said peptide is encoded by a gene located at chromosome 11 of the human genome at q23. Also provided are methods for the treatment of subject(s) suffering from immunodeficiency, developmental abnormality, inherited disease, or cancer by administering to said subject a therapeutically effective amount of one of the above-described agents (i.e., peptide, antagonist therefor, DNA encoding said peptide or antisense DNA derived therefrom). Also provided is a method for the diagnosis, in a subject, of immunodeficiency, developmental abnormality, inherited disease, or cancer associated with disruption of chromosome 11 at q23.

  7. Selective detection of carbohydrates and their peptide conjugates by ESI-MS using synthetic quaternary ammonium salt derivatives of phenylboronic acids.

    PubMed

    Kijewska, Monika; Kuc, Adam; Kluczyk, Alicja; Waliczek, Mateusz; Man-Kupisinska, Aleksandra; Lukasiewicz, Jolanta; Stefanowicz, Piotr; Szewczuk, Zbigniew

    2014-06-01

    We present new tags based on the derivatives of phenylboronic acid and apply them for the selective detection of sugars and peptide-sugar conjugates in mass spectrometry. We investigated the binding of phenylboronic acid and its quaternary ammonium salt (QAS) derivatives to carbohydrates and peptide-derived Amadori products by HR-MS and MS/MS experiments. The formation of complexes between sugar or sugar-peptide conjugates and synthetic tags was confirmed on the basis of the unique isotopic distribution resulting from the presence of boron atom. Moreover, incorporation of a quaternary ammonium salt dramatically improved the efficiency of ionization in mass spectrometry. It was found that the formation of a complex with phenylboronic acid stabilizes the sugar moiety in glycated peptides, resulting in simplification of the fragmentation pattern of peptide-derived Amadori products. The obtained results suggest that derivatization of phenylboronic acid as QAS is a promising method for sensitive ESI-MS detection of carbohydrates and their conjugates formed by non-enzymatic glycation or glycosylation.

  8. High or low dietary carbohydrate:protein ratios during first-feeding affect glucose metabolism and intestinal microbiota in juvenile rainbow trout.

    PubMed

    Geurden, I; Mennigen, J; Plagnes-Juan, E; Veron, V; Cerezo, T; Mazurais, D; Zambonino-Infante, J; Gatesoupe, J; Skiba-Cassy, S; Panserat, S

    2014-10-01

    Based on the concept of nutritional programming in mammals, we tested whether an acute hyperglucidic-hypoproteic stimulus during first feeding could induce long-term changes in nutrient metabolism in rainbow trout. Trout alevins received during the five first days of exogenous feeding either a hyperglucidic (40% gelatinized starch + 20% glucose) and hypoproteic (20%) diet (VLP diet) or a high-protein (60%) glucose-free diet (HP diet, control). Following a common 105-day period on a commercial diet, both groups were then challenged (65 days) with a carbohydrate-rich diet (28%). Short- and long-term effects of the early stimuli were evaluated in terms of metabolic marker gene expressions and intestinal microbiota as initial gut colonisation is essential for regulating the development of the digestive system. In whole alevins (short term), diet VLP relative to HP rapidly increased gene expressions of glycolytic enzymes, while those involved in gluconeogenesis and amino acid catabolism decreased. However, none of these genes showed persistent molecular adaptation in the liver of challenged juveniles (long term). By contrast, muscle of challenged juveniles subjected previously to the VLP stimulus displayed downregulated expression of markers of glycolysis and glucose transport (not seen in the short term). These fish also had higher plasma glucose (9 h postprandial), suggesting impaired glucose homeostasis induced by the early stimulus. The early stimulus did not modify the expression of the analysed metabolism-related microRNAs, but had short- and long-term effects on intestinal fungi (not bacteria) profiles. In summary, our data show that a short hyperglucidic-hypoproteic stimulus during early life may have a long-term influence on muscle glucose metabolism and intestinal microbiota in trout.

  9. High or low dietary carbohydrate:protein ratios during first-feeding affect glucose metabolism and intestinal microbiota in juvenile rainbow trout.

    PubMed

    Geurden, I; Mennigen, J; Plagnes-Juan, E; Veron, V; Cerezo, T; Mazurais, D; Zambonino-Infante, J; Gatesoupe, J; Skiba-Cassy, S; Panserat, S

    2014-10-01

    Based on the concept of nutritional programming in mammals, we tested whether an acute hyperglucidic-hypoproteic stimulus during first feeding could induce long-term changes in nutrient metabolism in rainbow trout. Trout alevins received during the five first days of exogenous feeding either a hyperglucidic (40% gelatinized starch + 20% glucose) and hypoproteic (20%) diet (VLP diet) or a high-protein (60%) glucose-free diet (HP diet, control). Following a common 105-day period on a commercial diet, both groups were then challenged (65 days) with a carbohydrate-rich diet (28%). Short- and long-term effects of the early stimuli were evaluated in terms of metabolic marker gene expressions and intestinal microbiota as initial gut colonisation is essential for regulating the development of the digestive system. In whole alevins (short term), diet VLP relative to HP rapidly increased gene expressions of glycolytic enzymes, while those involved in gluconeogenesis and amino acid catabolism decreased. However, none of these genes showed persistent molecular adaptation in the liver of challenged juveniles (long term). By contrast, muscle of challenged juveniles subjected previously to the VLP stimulus displayed downregulated expression of markers of glycolysis and glucose transport (not seen in the short term). These fish also had higher plasma glucose (9 h postprandial), suggesting impaired glucose homeostasis induced by the early stimulus. The early stimulus did not modify the expression of the analysed metabolism-related microRNAs, but had short- and long-term effects on intestinal fungi (not bacteria) profiles. In summary, our data show that a short hyperglucidic-hypoproteic stimulus during early life may have a long-term influence on muscle glucose metabolism and intestinal microbiota in trout. PMID:25274323

  10. Common Prairie feeds with different soluble and insoluble fractions used for CPM diet formulation in dairy cattle: impact of carbohydrate-protein matrix structure on protein and other primary nutrient digestion.

    PubMed

    Peng, Quanhui; Wang, Zhisheng; Zhang, Xuewei; Yu, Peiqiang

    2014-01-01

    An experiment was conducted to investigate the relationship of carbohydrates molecular spectral characteristics to rumen degradability of primary nutrients in Prairie feeds in dairy cattle. In total, 12 different types of feeds were selected, each type of feed was from three different source with total 37 samples. Six types of them were energy-sourced feeds and the others were protein-sourced feeds. The carbohydrates molecular spectral intensity of various functional groups were collected using Fourier transform infrared attenuated total reflectance (ATR-FT/IR) spectroscopy. In the in situ study, the results showed that the rumen digestibility and digestible fractions of primary nutrients (DM, OM, NCP, and CP) were significantly different (P<0.05) among the feeds. The spectral bands features were significantly different (P<0.05) among the feeds. Spectral intensities of A_Cell, H_1415 and H_1370 were weakly positively correlated with in situ rumen digestibility and digestible fractions of DM, OM and NCP. Spectral intensities of H_1150, H_1015, A_1, and A_3 were weakly negatively associated with in situ rumen degradation of CP. Spectral intensities of A_1240 and H_1240, mainly associated with cellulosic compounds, were correlated with rumen CP degradation. The multiple regression analysis demonstrated that the spectral intensities of A_3 and H_1415 played the most important role and could be used as a potential tool to predict rumen protein degradation of feeds in dairy cattle. In conclusion, this study showed that the carbohydrates as a whole have an effect on protein rumen degradation, rather than cellulose alone, indicating carbohydrate-protein matrix structure impact protein utilization in dairy cattle. The non-invasive molecular spectral technique (ATR-FT/IR) could be used as a rapid potential tool to predict rumen protein degradation of feedstuffs by using molecular spectral bands intensities in carbohydrate fingerprint region.

  11. Role of the AMP-activated protein kinase in regulating fatty acid metabolism during exercise.

    PubMed

    Steinberg, Gregory R

    2009-06-01

    During moderate-intensity exercise, fatty acids are the predominant substrate for working skeletal muscle. The release of fatty acids from adipose tissue stores, combined with the ability of skeletal muscle to actively fine tune the gradient between fatty acid and carbohydrate metabolism, depending on substrate availability and energetic demands, requires a coordinated system of metabolic control. Over the past decade, since the discovery that AMP-activated protein kinase (AMPK) was increased in accordance with exercise intensity, there has been significant interest in the proposed role of this ancient stress-sensing kinase as a critical integrative switch controlling metabolic responses during exercise. In this review, studies examining the role of AMPK as a regulator of fatty acid metabolism in both adipose tissue and skeletal muscle during exercise will be discussed. Exercise induces activation of AMPK in adipocytes and regulates triglyceride hydrolysis and esterfication through phosphorylation of hormone sensitive lipase (HSL) and glycerol-3-phosphate acyl-transferase, respectively. In skeletal muscle, exercise-induced activation of AMPK is associated with increases in fatty acid uptake, phosphorylation of HSL, and increased fatty acid oxidation, which is thought to occur via the acetyl-CoA carboxylase-malony-CoA-CPT-1 signalling axis. Despite the importance of AMPK in regulating fatty acid metabolism under resting conditions, recent evidence from transgenic models of AMPK deficiency suggest that alternative signalling pathways may also be important for the control of fatty acid metabolism during exercise.

  12. Site specific incorporation of keto amino acids into proteins

    DOEpatents

    Schultz, Peter G.; Wang, Lei

    2009-04-28

    Compositions and methods of producing components of protein biosynthetic machinery that include orthogonal tRNAs, orthogonal aminoacyl-tRNA synthetases, and orthogonal pairs of tRNAs/synthetases, which incorporate keto amino acids into proteins are provided. Methods for identifying these orthogonal pairs are also provided along with methods of producing proteins with keto amino acids using these orthogonal pairs.

  13. Site specific incorporation of keto amino acids into proteins

    DOEpatents

    Schultz, Peter G.; Wang, Lei

    2008-10-07

    Compositions and methods of producing components of protein biosynthetic machinery that include orthogonal tRNAs, orthogonal aminoacyl-tRNA synthetases, and orthogonal pairs of tRNAs/synthetases, which incorporate keto amino acids into proteins are provided. Methods for identifying these orthogonal pairs are also provided along with methods of producing proteins with keto amino acids using these orthogonal pairs.

  14. Site specific incorporation of keto amino acids into proteins

    SciTech Connect

    Schultz, Peter G.; Wang, Lei

    2012-02-14

    Compositions and methods of producing components of protein biosynthetic machinery that include orthogonal tRNAs, orthogonal aminoacyl-tRNA synthetases, and orthogonal pairs of tRNAs/synthetases, which incorporate keto amino acids into proteins are provided. Methods for identifying these orthogonal pairs are also provided along with methods of producing proteins with keto amino acids using these orthogonal pairs.

  15. Site specific incorporation of keto amino acids into proteins

    SciTech Connect

    Schultz, Peter G.; Wang, Lei

    2011-12-06

    Compositions and methods of producing components of protein biosynthetic machinery that include orthogonal tRNAs, orthogonal aminoacyl-tRNA synthetases, and orthogonal pairs of tRNAs/synthetases, which incorporate keto amino acids into proteins are provided. Methods for identifying these orthogonal pairs are also provided along with methods of producing proteins with keto amino acids using these orthogonal pairs.

  16. Site specific incorporation of keto amino acids into proteins

    SciTech Connect

    Schultz, Peter G.; Wang, Lei

    2011-03-22

    Compositions and methods of producing components of protein biosynthetic machinery that include orthogonal tRNAs, orthogonal aminoacyl-tRNA synthetases, and orthogonal pairs of tRNAs/synthetases, which incorporate keto amino acids into proteins are provided. Methods for identifying these orthogonal pairs are also provided along with methods of producing proteins with keto amino acids using these orthogonal pairs.

  17. A low carbohydrate, high protein diet suppresses intratumoral androgen synthesis and slows castration-resistant prostate tumor growth in mice.

    PubMed

    Fokidis, H Bobby; Yieng Chin, Mei; Ho, Victor W; Adomat, Hans H; Soma, Kiran K; Fazli, Ladan; Nip, Ka Mun; Cox, Michael; Krystal, Gerald; Zoubeidi, Amina; Tomlinson Guns, Emma S

    2015-06-01

    Dietary factors continue to preside as dominant influences in prostate cancer prevalence and progression-free survival following primary treatment. We investigated the influence of a low carbohydrate diet, compared to a typical Western diet, on prostate cancer (PCa) tumor growth in vivo. LNCaP xenograft tumor growth was studied in both intact and castrated mice, representing a more advanced castration resistant PCa (CRPC). No differences in LNCaP tumor progression (total tumor volume) with diet was observed for intact mice (P = 0.471) however, castrated mice on the Low Carb diet saw a statistically significant reduction in tumor growth rate compared with Western diet fed mice (P = 0.017). No correlation with serum PSA was observed. Steroid profiles, alongside serum cholesterol and cholesteryl ester levels, were significantly altered by both diet and castration. Specifically, DHT concentration with the Low Carb diet was 58% that of the CRPC-bearing mice on the Western diet. Enzymes in the steroidogenesis pathway were directly impacted and tumors isolated from intact mice on the Low Carb diet had higher AKR1C3 protein levels and lower HSD17B2 protein levels than intact mice on the Western diet (ARK1C3: P = 0.074; HSD17B2: P = 0.091, with α = 0.1). In contrast, CRPC tumors from mice on Low Carb diets had higher concentrations of both HSD17B2 (P = 0.016) and SRD5A1 (P = 0.058 with α = 0.1) enzymes. There was no correlation between tumor growth in castrated mice for Low Carb diet versus Western diet and (a) serum insulin (b) GH serum levels (c) insulin receptor (IR) or (d) IGF-1R in tumor tissue. Intact mice fed Western diet had higher serum insulin which was associated with significantly higher blood glucose and tumor tissue IR. We conclude that both diet and castration have a significant impact on the endocrinology of mice bearing LNCaP xenograft tumors. The observed effects of diet on cholesterol and steroid regulation impact tumor tissue DHT specifically and are

  18. A low carbohydrate, high protein diet suppresses intratumoral androgen synthesis and slows castration-resistant prostate tumor growth in mice.

    PubMed

    Fokidis, H Bobby; Yieng Chin, Mei; Ho, Victor W; Adomat, Hans H; Soma, Kiran K; Fazli, Ladan; Nip, Ka Mun; Cox, Michael; Krystal, Gerald; Zoubeidi, Amina; Tomlinson Guns, Emma S

    2015-06-01

    Dietary factors continue to preside as dominant influences in prostate cancer prevalence and progression-free survival following primary treatment. We investigated the influence of a low carbohydrate diet, compared to a typical Western diet, on prostate cancer (PCa) tumor growth in vivo. LNCaP xenograft tumor growth was studied in both intact and castrated mice, representing a more advanced castration resistant PCa (CRPC). No differences in LNCaP tumor progression (total tumor volume) with diet was observed for intact mice (P = 0.471) however, castrated mice on the Low Carb diet saw a statistically significant reduction in tumor growth rate compared with Western diet fed mice (P = 0.017). No correlation with serum PSA was observed. Steroid profiles, alongside serum cholesterol and cholesteryl ester levels, were significantly altered by both diet and castration. Specifically, DHT concentration with the Low Carb diet was 58% that of the CRPC-bearing mice on the Western diet. Enzymes in the steroidogenesis pathway were directly impacted and tumors isolated from intact mice on the Low Carb diet had higher AKR1C3 protein levels and lower HSD17B2 protein levels than intact mice on the Western diet (ARK1C3: P = 0.074; HSD17B2: P = 0.091, with α = 0.1). In contrast, CRPC tumors from mice on Low Carb diets had higher concentrations of both HSD17B2 (P = 0.016) and SRD5A1 (P = 0.058 with α = 0.1) enzymes. There was no correlation between tumor growth in castrated mice for Low Carb diet versus Western diet and (a) serum insulin (b) GH serum levels (c) insulin receptor (IR) or (d) IGF-1R in tumor tissue. Intact mice fed Western diet had higher serum insulin which was associated with significantly higher blood glucose and tumor tissue IR. We conclude that both diet and castration have a significant impact on the endocrinology of mice bearing LNCaP xenograft tumors. The observed effects of diet on cholesterol and steroid regulation impact tumor tissue DHT specifically and are

  19. Isolation of carbohydrate-metabolizing, extremely halophilic bacteria.

    NASA Technical Reports Server (NTRS)

    Tomlinson, G. A.; Hochstein, L. I.

    1972-01-01

    Four previously unrecognized strains of extremely halophilic bacteria that utilize carbohydrates have been isolated. Gas production proved an unreliable index of carbohydrate metabolism; therefore, carbohydrate utilization was measured by determining acid formation and sugar disappearance during growth. By these procedures, carbohydrate utilization was readily detected. The results suggest that carbohydrate dissimilation by extremely halophilic bacteria may be more common than previously thought and that the apparent rarity of carbohydrate-metabolizing halophiles may be an artifact of the isolation procedures used.

  20. Healthy carbohydrates

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Functional foods include dietary fiber consisting of health-promoting carbohydrates. We have produced novel prebiotics from orange peel and observed that they extend the shelf life of probiotic bacteria in synbiotics. Some pectic-oligosaccharides and xyloglucan-oligosaccharides also have anti-adhesi...

  1. Regulation of intestinal protein metabolism by amino acids.

    PubMed

    Bertrand, Julien; Goichon, Alexis; Déchelotte, Pierre; Coëffier, Moïse

    2013-09-01

    Gut homeostasis plays a major role in health and may be regulated by quantitative and qualitative food intake. In the intestinal mucosa, an intense renewal of proteins occurs, at approximately 50% per day in humans. In some pathophysiological conditions, protein turnover is altered and may contribute to intestinal or systemic diseases. Amino acids are key effectors of gut protein turnover, both as constituents of proteins and as regulatory molecules limiting intestinal injury and maintaining intestinal functions. Many studies have focused on two amino acids: glutamine, known as the preferential substrate of rapidly dividing cells, and arginine, another conditionally essential amino acid. The effects of glutamine and arginine on protein synthesis appear to be model and condition dependent, as are the involved signaling pathways. The regulation of gut protein degradation by amino acids has been minimally documented until now. This review will examine recent data, helping to better understand how amino acids regulate intestinal protein metabolism, and will explore perspectives for future studies.

  2. Abuse potential of carbohydrates for overweight carbohydrate cravers

    PubMed Central

    Spring, Bonnie; Schneider, Kristin; Smith, Malaina; Kendzor, Darla; Appelhans, Bradley; Hedeker, Donald; Pagoto, Sherry

    2010-01-01

    Rationale The long-rejected construct of food addiction is undergoing re-examination. Objectives . To evaluate whether a novel carbohydrate food shows abuse potential for rigorously defined carbohydrate cravers, as evidenced by selective self-administration and mood enhancement during double-blind discrimination testing. Methods Discrete trials choice testing was performed with 61 overweight (BMI m=27.64, SD=2.59) women (ages 18–45; 19.70% African American) whose diet records showed >4 weekly afternoon/evening emotional eating episodes confined to snacks with carbohydrate:protein ≥ 6:1. After being induced into a sad mood, participants were exposed, double-blind and in counterbalanced order, to taste-matched carbohydrate and protein beverages. They were asked to choose and self-administer the drink that made them feel better. Results Women overwhelmingly chose the carbohydrate beverage, even though blinded. Mixed-effects regression modeling, controlling for beverage order, revealed greater liking and greater reduction in dysphoria following the carbohydrate beverage compared to the protein beverage, but no differential effect on vigor. Conclusion For women who crave them, carbohydrates appear to display abuse potential, plausibly contributing to overconsumption and overweight. PMID:18273603

  3. Learning about Carbohydrates

    MedlinePlus

    ... Here's Help White House Lunch Recipes Learning About Carbohydrates KidsHealth > For Kids > Learning About Carbohydrates Print A ... of energy for the body. Two Types of Carbohydrates There are two major types of carbohydrates (or ...

  4. Ants farm subterranean aphids mostly in single clone groups - an example of prudent husbandry for carbohydrates and proteins?

    PubMed Central

    2012-01-01

    other aphids. We suggest that such culling of carbohydrate-providing symbionts for protein ingestion may maintain maximal host yield per aphid while also benefitting the domesticated aphids as long as their clone-mates reproduce successfully. The cost-benefit logic of this type of polyculture husbandry has striking analogies with human farming practices based on slaughtering young animals for meat to maximize milk-production by a carefully regulated adult livestock population. PMID:22747564

  5. Protein turnover, amino acid requirements and recommendations for athletes and active populations

    PubMed Central

    Poortmans, J.R.; Carpentier, A.; Pereira-Lancha, L.O.; Lancha, A.

    2012-01-01

    Skeletal muscle is the major deposit of protein molecules. As for any cell or tissue, total muscle protein reflects a dynamic turnover between net protein synthesis and degradation. Noninvasive and invasive techniques have been applied to determine amino acid catabolism and muscle protein building at rest, during exercise and during the recovery period after a single experiment or training sessions. Stable isotopic tracers (13C-lysine, 15N-glycine, 2H5-phenylalanine) and arteriovenous differences have been used in studies of skeletal muscle and collagen tissues under resting and exercise conditions. There are different fractional synthesis rates in skeletal muscle and tendon tissues, but there is no major difference between collagen and myofibrillar protein synthesis. Strenuous exercise provokes increased proteolysis and decreased protein synthesis, the opposite occurring during the recovery period. Individuals who exercise respond differently when resistance and endurance types of contractions are compared. Endurance exercise induces a greater oxidative capacity (enzymes) compared to resistance exercise, which induces fiber hypertrophy (myofibrils). Nitrogen balance (difference between protein intake and protein degradation) for athletes is usually balanced when the intake of protein reaches 1.2 g·kg−1·day−1 compared to 0.8 g·kg−1·day−1 in resting individuals. Muscular activities promote a cascade of signals leading to the stimulation of eukaryotic initiation of myofibrillar protein synthesis. As suggested in several publications, a bolus of 15-20 g protein (from skimmed milk or whey proteins) and carbohydrate (± 30 g maltodextrine) drinks is needed immediately after stopping exercise to stimulate muscle protein and tendon collagen turnover within 1 h. PMID:22666780

  6. Protein turnover, amino acid requirements and recommendations for athletes and active populations.

    PubMed

    Poortmans, J R; Carpentier, A; Pereira-Lancha, L O; Lancha Jr, A

    2012-10-01

    Skeletal muscle is the major deposit of protein molecules. As for any cell or tissue, total muscle protein reflects a dynamic turnover between net protein synthesis and degradation. Noninvasive and invasive techniques have been applied to determine amino acid catabolism and muscle protein building at rest, during exercise and during the recovery period after a single experiment or training sessions. Stable isotopic tracers ((13)C-lysine, (15)N-glycine, ²H5-phenylalanine) and arteriovenous differences have been used in studies of skeletal muscle and collagen tissues under resting and exercise conditions. There are different fractional synthesis rates in skeletal muscle and tendon tissues, but there is no major difference between collagen and myofibrillar protein synthesis. Strenuous exercise provokes increased proteolysis and decreased protein synthesis, the opposite occurring during the recovery period. Individuals who exercise respond differently when resistance and endurance types of contractions are compared. Endurance exercise induces a greater oxidative capacity (enzymes) compared to resistance exercise, which induces fiber hypertrophy (myofibrils). Nitrogen balance (difference between protein intake and protein degradation) for athletes is usually balanced when the intake of protein reaches 1.2 g · kg(-1) · day(-1) compared to 0.8 g · kg(-1) · day(-1) in resting individuals. Muscular activities promote a cascade of signals leading to the stimulation of eukaryotic initiation of myofibrillar protein synthesis. As suggested in several publications, a bolus of 15-20 g protein (from skimmed milk or whey proteins) and carbohydrate (± 30 g maltodextrine) drinks is needed immediately after stopping exercise to stimulate muscle protein and tendon collagen turnover within 1 h. PMID:22666780

  7. Daily Overfeeding from Protein and/or Carbohydrate Supplementation for Eight Weeks in Conjunction with Resistance Training Does not Improve Body Composition and Muscle Strength or Increase Markers Indicative of Muscle Protein Synthesis and Myogenesis in Resistance-Trained Males

    PubMed Central

    Spillane, Mike; Willoughby, Darryn S.

    2016-01-01

    This study determined the effects of heavy resistance training and daily overfeeding with carbohydrate and/or protein on blood and skeletal muscle markers of protein synthesis (MPS), myogenesis, body composition, and muscle performance. Twenty one resistance-trained males were randomly assigned to either a protein + carbohydrate [HPC (n = 11)] or a carbohydrate [HC (n = 10)] supplement group in a double-blind fashion. Body composition and muscle performance were assessed, and venous blood samples and muscle biopsies were obtained before and after eight weeks of resistance training and supplementation. Data were analyzed by two-way ANOVA (p ≤ 0.05). Total body mass, body water, and fat mass were significantly increased in both groups in response to resistance training, but not supplementation (p < 0.05); however, lean mass was not significantly increased in either group (p = 0.068). Upper- (p = 0.024) and lower-body (p = 0.001) muscle strength and myosin heavy chain (MHC) 1 (p = 0.039) and MHC 2A (p = 0.027) were also significantly increased with resistance training. Serum IGF-1, GH, and HGF were not significantly affected (p > 0.05). Muscle total DNA, total protein, and c-Met were not significantly affected (p > 0.05). In conjunction with resistance training, the peri-exercise and daily overfeeding of protein and/or carbohydrate did not preferentially improve body composition, muscle performance, and markers indicative of MPS and myogenic activation. Key points In response to 56 days of heavy resistance training and HC or HPC supplementation, similar increases in muscle mass and strength in both groups occurred; however, the increases were not different between supplement groups. The supplementation of HPC had no preferential effect on augmenting serum IGF-1 GH, or HGF. The supplementation of HPC had no preferential effect on augmenting increases in total muscle protein content or the myogenic markers, total DNA and muscle cMet content. In response to 56 days of

  8. Daily Overfeeding from Protein and/or Carbohydrate Supplementation for Eight Weeks in Conjunction with Resistance Training Does not Improve Body Composition and Muscle Strength or Increase Markers Indicative of Muscle Protein Synthesis and Myogenesis in Resistance-Trained Males.

    PubMed

    Spillane, Mike; Willoughby, Darryn S

    2016-03-01

    This study determined the effects of heavy resistance training and daily overfeeding with carbohydrate and/or protein on blood and skeletal muscle markers of protein synthesis (MPS), myogenesis, body composition, and muscle performance. Twenty one resistance-trained males were randomly assigned to either a protein + carbohydrate [HPC (n = 11)] or a carbohydrate [HC (n = 10)] supplement group in a double-blind fashion. Body composition and muscle performance were assessed, and venous blood samples and muscle biopsies were obtained before and after eight weeks of resistance training and supplementation. Data were analyzed by two-way ANOVA (p ≤ 0.05). Total body mass, body water, and fat mass were significantly increased in both groups in response to resistance training, but not supplementation (p < 0.05); however, lean mass was not significantly increased in either group (p = 0.068). Upper- (p = 0.024) and lower-body (p = 0.001) muscle strength and myosin heavy chain (MHC) 1 (p = 0.039) and MHC 2A (p = 0.027) were also significantly increased with resistance training. Serum IGF-1, GH, and HGF were not significantly affected (p > 0.05). Muscle total DNA, total protein, and c-Met were not significantly affected (p > 0.05). In conjunction with resistance training, the peri-exercise and daily overfeeding of protein and/or carbohydrate did not preferentially improve body composition, muscle performance, and markers indicative of MPS and myogenic activation. Key pointsIn response to 56 days of heavy resistance training and HC or HPC supplementation, similar increases in muscle mass and strength in both groups occurred; however, the increases were not different between supplement groups.The supplementation of HPC had no preferential effect on augmenting serum IGF-1 GH, or HGF.The supplementation of HPC had no preferential effect on augmenting increases in total muscle protein content or the myogenic markers, total DNA and muscle cMet content.In response to 56 days of a

  9. Nonfeed application of rendered animal proteins for microbial production of eicosapentaenoic acid by the fungus Pythium irregulare.

    PubMed

    Liang, Yi; Garcia, Rafael A; Piazza, George J; Wen, Zhiyou

    2011-11-23

    Rendered animal proteins are well suited for animal nutrition applications, but the market is maturing, and there is a need to develop new uses for these products. The objective of this study is to explore the possibility of using animal proteins as a nutrient source for microbial production of omega-3 polyunsaturated fatty acids by the microalga Schizochytrium limacinum and the fungus Pythium irregulare. To be absorbed by the microorganisms, the proteins needed to be hydrolyzed into small peptides and free amino acids. The utility of the protein hydrolysates for microorganisms depended on the hydrolysis method used and the type of microorganism. The enzymatic hydrolysates supported better cell growth performance than the alkali hydrolysates did. P. irregulare displayed better overall growth performance on the experimental hydrolysates compared to S. limacinum. When P. irregulare was grown in medium containing 10 g/L enzymatic hydrolysate derived from meat and bone meal or feather meal, the performance of cell growth, lipid synthesis, and omega-3 fatty acid production was comparable to the that of culture using commercial yeast extract. The fungal biomass derived from the animal proteins had 26-29% lipid, 32-34% protein, 34-39% carbohydrate, and <2% ash content. The results show that it is possible to develop a nonfeed application for rendered animal protein by hydrolysis of the protein and feeding to industrial microorganisms which can produce omega-3 fatty acids for making omega-3-fortified foods or feeds.

  10. Carbohydrate intake.

    PubMed

    Leturque, Armelle; Brot-Laroche, Edith; Le Gall, Maude

    2012-01-01

    Carbohydrates represent more than 50% of the energy sources present in most human diets. Sugar intake is regulated by metabolic, neuronal, and hedonic factors, and gene polymorphisms are involved in determining sugar preference. Nutrigenomic adaptations to carbohydrate availability have been evidenced in metabolic diseases, in the persistence of lactose digestion, and in amylase gene copy number. Furthermore, dietary oligosaccharides, fermentable by gut flora, can modulate the microbiotal diversity to the benefit of the host. Genetic diseases linked to mutations in the disaccharidase genes (sucrase-isomaltase, lactase) and in sugar transporter genes (sodium/glucose cotransporter 1, glucose transporters 1 and 2) severely impact carbohydrate intake. These diseases are revealed upon exposure to food containing the offending sugar, and withdrawal of this sugar from the diet prevents disease symptoms, failure to thrive, and premature death. Tailoring the sugar composition of diets to optimize wellness and to prevent the chronic occurrence of metabolic diseases is a future goal that may yet be realized through continued development of nutrigenetics and nutrigenomics approaches. PMID:22656375

  11. Terrestrial carbohydrates support freshwater zooplankton during phytoplankton deficiency

    PubMed Central

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

    2016-01-01

    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. PMID:27510848

  12. Terrestrial carbohydrates support freshwater zooplankton during phytoplankton deficiency.

    PubMed

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

    2016-01-01

    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. PMID:27510848

  13. Post-exercise whey protein hydrolysate supplementation induces a greater increase in muscle protein synthesis than its constituent amino acid content.

    PubMed

    Kanda, Atsushi; Nakayama, Kyosuke; Fukasawa, Tomoyuki; Koga, Jinichiro; Kanegae, Minoru; Kawanaka, Kentaro; Higuchi, Mitsuru

    2013-09-28

    It is well known that ingestion of a protein source is effective in stimulating muscle protein synthesis after exercise. In addition, there are numerous reports on the impact of leucine and leucine-rich whey protein on muscle protein synthesis and mammalian target of rapamycin (mTOR) signalling. However, there is only limited information on the effects of whey protein hydrolysates (WPH) on muscle protein synthesis and mTOR signalling. The aim of the present study was to compare the effects of WPH and amino acids on muscle protein synthesis and the initiation of translation in skeletal muscle during the post-exercise phase. Male Sprague–Dawley rats swam for 2 h to depress muscle protein synthesis. Immediately after exercise, the animals were administered either carbohydrate (CHO), CHO plus an amino acid mixture (AA) or CHO plus WPH. At 1 h after exercise, the supplements containing whey-based protein (AA and WPH) caused a significant increase in the fractional rate of protein synthesis (FSR) compared with CHO. WPH also caused a significant increase in FSR compared with AA. Post-exercise ingestion of WPH caused a significant increase in the phosphorylation of mTOR levels compared with AA or CHO. In addition, WPH caused greater phosphorylation of ribosomal protein S6 kinase and eukaryotic initiation factor 4E-binding protein 1 than AA and CHO. In contrast, there was no difference in plasma amino acid levels following supplementation with either AA or WPH. These results indicate that WPH may include active components that are superior to amino acids for stimulating muscle protein synthesis and initiating translation.

  14. Binding of Sperm to the Zona Pellucida Mediated by Sperm Carbohydrate-Binding Proteins is not Species-Specific in Vitro between Pigs and Cattle.

    PubMed

    Takahashi, Kazuya; Kikuchi, Kazuhiro; Uchida, Yasuomi; Kanai-Kitayama, Saeko; Suzuki, Reiichiro; Sato, Reiko; Toma, Kazunori; Geshi, Masaya; Akagi, Satoshi; Nakano, Minoru; Yonezawa, Naoto

    2013-01-01

    Carbohydrates are candidates for the basis of species-selective interaction of gametes during mammalian fertilization. In this study, we sought to clarify the roles of sugar residues in the species-selective, sperm-oocyte interaction in pigs and cattle. Acrosome-intact porcine and bovine sperm exhibited their strongest binding affinities for β-Gal and α-Man residues, respectively. Porcine-sperm specificity changed from β-Gal to α-Man after the acrosome reaction, while bovine-sperm specificity did not. Binding of acrosome-intact and acrosome-reacted sperm decreased after trypsinization, indicating that the carbohydrate-binding components are proteins. While immature oocytes bound homologous sperm preferentially to heterologous sperm, oocytes matured in vitro bound similar numbers of homologous and heterologous sperm. Lectin staining revealed the aggregation of α-Man residues on the outer surface of the porcine zona during maturation. In both species, zona-free, mature oocytes bound homologous sperm preferentially to heterologous sperm. The lectin-staining patterns of the zona pellucida and zona-free oocytes coincided with the carbohydrate-binding specificities of acrosome-intact and acrosome-reacted sperm, respectively, supporting the involvement of carbohydrates in gamete recognition in pigs and cattle. These results also indicate that sperm-zona pellucida and sperm-oolemma bindings are not strictly species-specific in pigs and cattle, and further suggest that sperm penetration into the zona and/or fusion with oolemma may be species-specific between pigs and cattle.

  15. AMP-activated protein kinase and ATP-citrate lyase are two distinct molecular targets for ETC-1002, a novel small molecule regulator of lipid and carbohydrate metabolism[S

    PubMed Central

    Pinkosky, Stephen L.; Filippov, Sergey; Srivastava, Rai Ajit K.; Hanselman, Jeffrey C.; Bradshaw, Cheryl D.; Hurley, Timothy R.; Cramer, Clay T.; Spahr, Mark A.; Brant, Ashley F.; Houghton, Jacob L.; Baker, Chris; Naples, Mark; Adeli, Khosrow; Newton, Roger S.

    2013-01-01

    ETC-1002 (8-hydroxy-2,2,14,14-tetramethylpentadecanedioic acid) is a novel investigational drug being developed for the treatment of dyslipidemia and other cardio-metabolic risk factors. The hypolipidemic, anti-atherosclerotic, anti-obesity, and glucose-lowering properties of ETC-1002, characterized in preclinical disease models, are believed to be due to dual inhibition of sterol and fatty acid synthesis and enhanced mitochondrial long-chain fatty acid β-oxidation. However, the molecular mechanism(s) mediating these activities remained undefined. Studies described here show that ETC-1002 free acid activates AMP-activated protein kinase in a Ca2+/calmodulin-dependent kinase β-independent and liver kinase β 1-dependent manner, without detectable changes in adenylate energy charge. Furthermore, ETC-1002 is shown to rapidly form a CoA thioester in liver, which directly inhibits ATP-citrate lyase. These distinct molecular mechanisms are complementary in their beneficial effects on lipid and carbohydrate metabolism in vitro and in vivo. Consistent with these mechanisms, ETC-1002 treatment reduced circulating proatherogenic lipoproteins, hepatic lipids, and body weight in a hamster model of hyperlipidemia, and it reduced body weight and improved glycemic control in a mouse model of diet-induced obesity. ETC-1002 offers promise as a novel therapeutic approach to improve multiple risk factors associated with metabolic syndrome and benefit patients with cardiovascular disease. PMID:23118444

  16. Changes in intake of protein foods, carbohydrate amount and quality, and long-term weight change: results from 3 prospective cohorts1234

    PubMed Central

    Hou, Tao; Ludwig, David S; Rimm, Eric B; Willett, Walter; Hu, Frank B; Mozaffarian, Dariush

    2015-01-01

    Background: Dietary guidelines recommend interchanging protein foods (e.g., chicken for red meat), but they may be exchanged for carbohydrate-rich foods varying in quality [glycemic load (GL)]. Whether such exchanges occur and how they influence long-term weight gain are not established. Objective: Our objective was to determine how changes in intake of protein foods, GL, and their interrelationship influence long-term weight gain. Design: We investigated the association between 4-y changes in consumption of protein foods, GL, and their interaction with 4-y weight change over a 16- to 24-y follow-up, adjusted for other lifestyle changes (smoking, physical activity, television watching, sleep duration), body mass index, and all dietary factors simultaneously in 3 prospective US cohorts (Nurses’ Health Study, Nurses’ Health Study II, and Health Professionals Follow-Up Study) comprising 120,784 men and women free of chronic disease or obesity at baseline. Results: Protein foods were not interchanged with each other (intercorrelations typically <|0.05|) but with carbohydrate (negative correlation as low as −0.39). Protein foods had different relations with long-term weight gain, with positive associations for meats, chicken with skin, and regular cheese (per increased serving/d, 0.13–1.17 kg; P = 0.02 to P < 0.001); no association for milk, legumes, peanuts, or eggs (P > 0.40 for each); and relative weight loss for yogurt, peanut butter, walnuts, other nuts, chicken without skin, low-fat cheese, and seafood (−0.14 to −0.71 kg; P = 0.01 to P < 0.001). Increases in GL were independently associated with a 0.42-kg greater weight gain per 50-unit increase (P < 0.001). Significant interactions (P-interaction < 0.05) between changes in protein foods and GL were identified; for example, increased cheese intake was associated with weight gain when GL increased, with weight stability when GL did not change, and with weight loss when exchanged for GL (i.e., decrease

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

    PubMed

    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.

  18. Carbohydrate Recognition Properties of Human Ficolins

    PubMed Central

    Gout, Evelyne; Garlatti, Virginie; Smith, David F.; Lacroix, Monique; Dumestre-Pérard, Chantal; Lunardi, Thomas; Martin, Lydie; Cesbron, Jean-Yves; Arlaud, Gérard J.; Gaboriaud, Christine; Thielens, Nicole M.

    2010-01-01

    Ficolins are oligomeric innate immune recognition proteins consisting of a collagen-like region and a fibrinogen-like recognition domain that bind to pathogen- and apoptotic cell-associated molecular patterns. To investigate their carbohydrate binding specificities, serum-derived L-ficolin and recombinant H- and M-ficolins were fluorescently labeled, and their carbohydrate binding ability was analyzed by glycan array screening. L-ficolin preferentially recognized disulfated N-acetyllactosamine and tri- and tetrasaccharides containing terminal galactose or N-acetylglucosamine. Binding was sensitive to the position and orientation of the bond between N-acetyllactosamine and the adjacent carbohydrate. No significant binding of H-ficolin to any of the 377 glycans probed could be detected, providing further evidence for its poor lectin activity. M-ficolin bound preferentially to 9-O-acetylated 2-6-linked sialic acid derivatives and to various glycans containing sialic acid engaged in a 2-3 linkage. To further investigate the structural basis of sialic acid recognition by M-ficolin, point mutants were produced in which three residues of the fibrinogen domain were replaced by their counterparts in L-ficolin. Mutations G221F and A256V inhibited binding to the 9-O-acetylated sialic acid derivatives, whereas Y271F abolished interaction with all sialic acid-containing glycans. The crystal structure of the Y271F mutant fibrinogen domain was solved, showing that the mutation does not alter the structure of the ligand binding pocket. These analyses reveal novel ficolin ligands such as sulfated N-acetyllactosamine (L-ficolin) and gangliosides (M-ficolin) and provide precise insights into the sialic acid binding specificity of M-ficolin, emphasizing the essential role of Tyr271 in this respect. PMID:20032467

  19. Protein, amino acids and the control of food intake.

    PubMed

    Tome, Daniel

    2004-08-01

    The influence of protein and amino acid on the control of food intake and the specific control of protein and amino acid intakes remains incompletely understood. The most commonly accepted conclusions are: (1) the existence of an aversive response to diets deficient in or devoid of protein or deficient in at least one essential amino acid; (2) the existence of a mechanism that enables attainment of the minimum requirement for N and essential amino acids by increasing intake of a low-protein diet; (3) a decrease in the intake of a high-protein diet is associated with different processes, including the high satiating effect of protein. Ingested proteins are believed to generate pre- and post-absorptive signals that contribute to the control of gastric kinetics, pancreatic secretion and food intake. At the brain level, two major afferent pathways are involved in protein and amino acid monitoring: the indirect neuro-mediated (mainly vagus-mediated) pathway and the direct blood pathway. The neuro-mediated pathway transfers pre-absorptive and visceral information. This information is for the main part transferred through the vagus nerve that innervates part of the oro-sensory zone: the stomach, the duodenum and the liver. Other information is directly monitored in the blood. It is likely that the system responds precisely when protein and essential amino acid intake is inadequate, but in contrast allows a large range of adaptive capacities through amino acid degradation and substrate interconversion.

  20. Echinococcus granulosus fatty acid binding proteins subcellular localization.

    PubMed

    Alvite, Gabriela; Esteves, Adriana

    2016-05-01

    Two fatty acid binding proteins, EgFABP1 and EgFABP2, were isolated from the parasitic platyhelminth Echinococcus granulosus. These proteins bind fatty acids and have particular relevance in flatworms since de novo fatty acids synthesis is absent. Therefore platyhelminthes depend on the capture and intracellular distribution of host's lipids and fatty acid binding proteins could participate in lipid distribution. To elucidate EgFABP's roles, we investigated their intracellular distribution in the larval stage by a proteomic approach. Our results demonstrated the presence of EgFABP1 isoforms in cytosolic, nuclear, mitochondrial and microsomal fractions, suggesting that these molecules could be involved in several cellular processes.

  1. Role of Ingested Amino Acids and Protein in the Promotion of Resistance Exercise-Induced Muscle Protein Anabolism.

    PubMed

    Reidy, Paul T; Rasmussen, Blake B

    2016-02-01

    The goal of this critical review is to comprehensively assess the evidence for the molecular, physiologic, and phenotypic skeletal muscle responses to resistance exercise (RE) combined with the nutritional intervention of protein and/or amino acid (AA) ingestion in young adults. We gathered the literature regarding the translational response in human skeletal muscle to acute exposure to RE and protein/AA supplements and the literature describing the phenotypic skeletal muscle adaptation to RE and nutritional interventions. Supplementation of protein/AAs with RE exhibited clear protein dose-dependent effects on translational regulation (protein synthesis) through mammalian target of rapamycin complex 1 (mTORC1) signaling, which was most apparent through increases in p70 ribosomal protein S6 kinase 1 (S6K1) phosphorylation, compared with postexercise recovery in the fasted or carbohydrate-fed state. These acute findings were critically tested via long-term exposure to RE training (RET) and protein/AA supplementation, and it was determined that a diminishing protein/AA supplement effect occurs over a prolonged exposure stimulus after exercise training. Furthermore, we found that protein/AA supplements, combined with RET, produced a positive, albeit minor, effect on the promotion of lean mass growth (when assessed in >20 participants/treatment); a negligible effect on muscle mass; and a negligible to no additional effect on strength. A potential concern we discovered was that the majority of the exercise training studies were underpowered in their ability to discern effects of protein/AA supplementation. Regardless, even when using optimal methodology and large sample sizes, it is clear that the effect size for protein/AA supplementation is low and likely limited to a subset of individuals because the individual variability is high. With regard to nutritional intakes, total protein intake per day, rather than protein timing or quality, appears to be more of a factor on

  2. Contribution of polyunsaturated fatty acids to intestinal repair in protein-energy malnutrition.

    PubMed

    Nieto, Natalia; Mesa, María Dolores; López-Pedrosa, José María; Torres, M Isabel; Ríos, Antonio; Suárez, María Dolores; Gil, Angel

    2007-06-01

    The aim of this study was to assess the effect of polyunsaturated fatty acids supplied in the diet on intestinal mucosa repair in a rat model of protein-energy malnutrition. Rats were fed either a standard semipurified diet or the same diet containing lactose as the only source of carbohydrate to cause protein-energy malnutrition. Diarrhea was induced within 24 h and was maintained for 2 weeks, after which both groups of rats were fed for 1 week either the standard diet or the standard diet supplemented with different sources of fatty acids, such as olive oil (OO), fish oil (FO), and purified phospholipids from pig brain (BPL). The lactose-enriched diet caused loss of enterocyte microvilli, lymphocyte infiltration, supranuclear cytoplasmic vesiculation, decreased number of goblet cells, low-density enlarged mitochondria, and less cristae. The FO diet improved the pathology score according to the histological and ultrastructural analysis, with an increased number of goblet cells, ratio of microvilli length to crypt depth, and percentage of intraepithelial lymphocytes compared to those found in rats with protein-energy malnutrition. We previously reported that chronic diarrhea depletes the antioxidant defense in rat intestine; we now show that both, the FO and the BPL diets, increase GSH levels in colon and that some antioxidant enzyme activities vary according to the source of fatty acids, with higher catalase and superoxide dismutase by the FO diet in jejunum, increased catalase by the BPL diet in jejunum, and elevated glutathione peroxidase by the OO diet in colon. The fatty acid profile of intestinal mucosa reflects the source of fat in the diet, with the lowest ratio of n-6/n-3 for rats fed the FO diet. These results suggest that dietary polyunsaturated fatty acids, particularly those in the n-3 series, may play an important role in intestinal repair in chronic diarrhea due to protein-energy malnutrition.

  3. Repression of the glucose-inducible outer-membrane protein OprB during utilization of aromatic compounds and organic acids in Pseudomonas putida CSV86.

    PubMed

    Shrivastava, Rahul; Basu, Bhakti; Godbole, Ashwini; Mathew, M K; Apte, Shree K; Phale, Prashant S

    2011-05-01

    Pseudomonas putida CSV86 shows preferential utilization of aromatic compounds over glucose. Protein analysis and [¹⁴C]glucose-binding studies of the outer membrane fraction of cells grown on different carbon sources revealed a 40 kDa protein that was transcriptionally induced by glucose and repressed by aromatics and succinate. Based on 2D gel electrophoresis and liquid chromatography-tandem mass spectrometry analysis, the 40 kDa protein closely resembled the porin B of P. putida KT2440 and carbohydrate-selective porin OprB of various Pseudomonas strains. The purified native protein (i) was estimated to be a homotrimer of 125 kDa with a subunit molecular mass of 40 kDa, (ii) displayed heat modifiability of electrophoretic mobility, (iii) showed channel conductance of 166 pS in 1 M KCl, (iv) permeated various sugars (mono-, di- and tri-saccharides), organic acids, amino acids and aromatic compounds, and (v) harboured a glucose-specific and saturable binding site with a dissociation constant of 1.3 µM. These results identify the glucose-inducible outer-membrane protein of P. putida CSV86 as a carbohydrate-selective protein OprB. Besides modulation of intracellular glucose-metabolizing enzymes and specific glucose-binding periplasmic space protein, the repression of OprB by aromatics and organic acids, even in the presence of glucose, also contributes significantly to the strain's ability to utilize aromatics and organic acids over glucose.

  4. Amino acid sequences of proteins from Leptospira serovar pomona.

    PubMed

    Alves, S F; Lefebvre, R B; Probert, W

    2000-01-01

    This report describes a partial amino acid sequences from three putative outer envelope proteins from Leptospira serovar pomona. In order to obtain internal fragments for protein sequencing, enzymatic and chemical digestion was performed. The enzyme clostripain was used to digest the proteins 32 and 45 kDa. In situ digestion of 40 kDa molecular weight protein was accomplished using cyanogen bromide. The 32 kDa protein generated two fragments, one of 21 kDa and another of 10 kDa that yielded five residues. A fragment of 24 kDa that yielded nineteen residues of amino acids was obtained from 45 kDa protein. A fragment with a molecular weight of 20 kDa, yielding a twenty amino acids sequence from the 40 kDa protein.

  5. Protein quality of supplements and meal replacements. Amino acids and calculated indicators of protein quality.

    PubMed

    Marable, N L; Hinners, M L; Hardison, N W; Kehrberg, N L

    1980-09-01

    The amino acid composition of several types of dietary supplements and meal replacements was measured and compared with label values when available and to published values for egg. Calculated indicators of protein quality, such as chemical score, protein calorie:total calorie ratio, individual essential amino acid:total essential amino acid ratio, and total essential amino acid:total amino acid ratio were also compared for products, egg, and the estimated pattern of adult requirements. Predigested liquid protein products were notably lower in protein quality than other products. All non-predigested products compared favorably with egg in terms of protein quality, but were more expensive and had no advantages over regular meals in terms of protein quality as reducing aids or protein supplements.

  6. Role of different additives and metallic micro minerals on the enhanced citric acid production by Aspergillus niger MNNG-115 using different carbohydrate materials.

    PubMed

    Ali, Sikander; Haq, Ikram-ul

    2005-01-01

    The present investigation deals with the promotry effect of different additives and metallic micro minerals on citric acid production by Aspergillus niger MNNG-115 using different carbohydrate materials. For this, sugar cane bagasse was fortified with sucrose salt medium. Ethanol and coconut oil at 3.0% (v/w) level increased citric acid productivity. Fluoroacetate at a concentration of 1.0 mg/ml bagasse enhanced the yield of citric acid significantly. However, the addition of ethanol and fluoroacetate after 6 h of growth gave the maximum conversion of available sugar to citric acid. In another study, influence of some metallic micro-minerals viz. copper sulphate, molybdenum sulphate, zinc sulphate and cobalt sulphate on microbial synthesis of citric acid using molasses medium was also carried out. It was found that copper sulphate and molybdenum sulphate remarkably enhanced the production of citric acid while zinc sulphate was not so effective. However, cobalt sulphate was the least effective for microbial biosynthesis of citric acid under the same experimental conditions. In case of CuSO(4), the strain of Aspergillus niger MNNG-115 showed enhanced citric productivity with experimental (9.80%) over the control (7.54%). In addition, the specific productivity of the culture at 30 ppm CuSO(4) (Q(p) = 0.012a g/g cells/h) was several folds higher than other all other concentrations. All kinetic parameters including yield coefficients and volumetric rates revealed the hyper productivity of citric acid by CuSO(4) using blackstrap molasses as the basal carbon source.

  7. Protein and amino acid metabolism and requirements

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Proteins are the major structural and functional components of all cells of the body. Enzymes, membrane carriers, blood transport molecules, intracellular matrix, and even hair and fingernails are proteins, as are many hormones. Proteins also constitute a major portion of all membranes, and the cons...

  8. Phosphate acceptor amino acid residues in structural proteins of rhabdoviruses.

    PubMed

    Sokol, F; Tan, K B; McFalls, M L; Madore, P

    1974-07-01

    Partial acid hydrolysates of the [(32)P]phosphate- or [(3)H]serine-labeled proteins of purified vesicular stomatitis, rabies, Lagos bat, Mokola, or spring viremia of carp virions and of purified intracellular nucleocapsids of these viruses have been analyzed by paper electrophoresis for the presence of phosphorylated amino acids. Both phosphoserine and phosphothreonine, with the former predominant, were present in virion and nucleocapsid preparations that contained phosphoproteins. An exception was the fish rhabdovirus, which contained only phosphoserine. When vesicular stomatitis or rabies virus proteins were phosphorylated in a cell-free system by the virion-associated protein kinase and analyzed for the presence of phosphorylated amino acid residues, phosphoserine was again found to be more abundant than phosphothreonine. After in vitro protein phosphorylation, another phospho-compound, possibly a third phosphoamino acid, was detected in the partial acid hydrolysates of these viruses. PMID:4365328

  9. Measuring protein-protein and protein-nucleic Acid interactions by biolayer interferometry.

    PubMed

    Sultana, Azmiri; Lee, Jeffrey E

    2015-01-01

    Biolayer interferometry (BLI) is a simple, optical dip-and-read system useful for measuring interactions between proteins, peptides, nucleic acids, small molecules, and/or lipids in real time. In BLI, a biomolecular bait is immobilized on a matrix at the tip of a fiber-optic sensor. The binding between the immobilized ligand and another molecule in an analyte solution produces a change in optical thickness at the tip and results in a wavelength shift proportional to binding. BLI provides direct binding affinities and rates of association and dissociation. This unit describes an efficient approach using streptavidin-based BLI to analyze DNA-protein and protein-protein interactions. A quantitative set of equilibrium binding affinities (K(d)) and rates of association and dissociation (k(a)/k(d)) can be measured in minutes using nanomole quantities of sample.

  10. Interaction of milk whey protein with common phenolic acids

    NASA Astrophysics Data System (ADS)

    Zhang, Hao; Yu, Dandan; Sun, Jing; Guo, Huiyuan; Ding, Qingbo; Liu, Ruihai; Ren, Fazheng

    2014-01-01

    Phenolics-rich foods such as fruit juices and coffee are often consumed with milk. In this study, the interactions of α-lactalbumin and β-lactoglobulin with the phenolic acids (chlorogenic acid, caffeic acid, ferulic acid, and coumalic acid) were examined. Fluorescence, CD, and FTIR spectroscopies were used to analyze the binding modes, binding constants, and the effects of complexation on the conformation of whey protein. The results showed that binding constants of each whey protein-phenolic acid interaction ranged from 4 × 105 to 7 × 106 M-n and the number of binding sites n ranged from 1.28 ± 0.13 to 1.54 ± 0.34. Because of these interactions, the conformation of whey protein was altered, with a significant reduction in the amount of α-helix and an increase in the amounts of β-sheet and turn structures.

  11. High Glucose-induced O-GlcNAcylated Carbohydrate Response Element-binding Protein (ChREBP) Mediates Mesangial Cell Lipogenesis and Fibrosis

    PubMed Central

    Park, Min-Jung; Kim, Dong-Il; Lim, Seul-Ki; Choi, Joo-Hee; Han, Ho-Jae; Yoon, Kyung-Chul; Park, Soo-Hyun

    2014-01-01

    Carbohydrate response element-binding protein (ChREBP) is a transcription factor responsible for carbohydrate metabolism in the liver. However, the role of ChREBP in diabetic nephropathy has not been elucidated. Thus, we investigated the role of ChREBP in mesangial cells in diabetic nephropathy. Treatment with 25 mm glucose (high glucose; HG) increased cellular O-GlcNAc and O-GlcNAcylated ChREBP in mesangial cells compared with normal 5.5 mm glucose. O-(2-acetamido-2-deoxy-d-glucopyranosylidene) amino N-phenylcarbamate (PUGNAc), a drug that increases O-GlcNAc, augmented the expression of ChREBP targets, whereas DON, a drug that decreases O-GlcNAc and O-GlcNAcase overexpression, mitigated the increase with HG. O-GlcNAc augmented the protein stability, transcriptional activity, and nuclear translocation of ChREBP. HG treatment also stimulated lipid accumulation and the contents of triglyceride and cholesterol in mesangial cells. In addition, HG triggered expression of hypoxia-inducible factor 1-α, vascular endothelial growth factor, and extracellular matrix components related to nephrosclerosis. The ChREBP mutant, W130A, did not exhibit HG-induced lipid accumulation and fibrotic proteins, suggesting that the Trp-130 residue in the MCR3 domain is important in the development of glomerulosclerosis. O-GlcNAcylated ChREBP was elevated in mesangium cells of streptozotocin-induced diabetic rats. In conclusion, HG increased the O-GlcNAcylated ChREBP level, which resulted in lipid accumulation and up-regulation of fibrotic proteins in mesangial cells. These effects may lead mesangial cells to an ultimately pathological state. PMID:24616092

  12. Automated protein hydrolysis delivering sample to a solid acid catalyst for amino acid analysis.

    PubMed

    Masuda, Akiko; Dohmae, Naoshi

    2010-11-01

    In this study, we developed an automatic protein hydrolysis system using strong cation-exchange resins as solid acid catalysts. Examining several kinds of inorganic solid acids and cation-exchange resins, we found that a few cation-exchange resins worked as acid catalysts for protein hydrolysis when heated in the presence of water. The most efficient resin yielded amounts of amino acids that were over 70% of those recovered after conventional hydrolysis with hydrochloric acid and resulted in amino acid compositions matching the theoretical values. The solid-acid hydrolysis was automated by packing the resin into columns, combining the columns with a high-performance liquid chromatography system, and heating them. The amino acids that constitute a protein can thereby be determined, minimizing contamination from the environment.

  13. Assessment on proximate composition, dietary fiber, phytic acid and protein hydrolysis of germinated Ecuatorian brown rice.

    PubMed

    Cáceres, Patricio J; Martínez-Villaluenga, Cristina; Amigo, Lourdes; Frias, Juana

    2014-09-01

    Germinated brown rice (GBR) is considered healthier than brown rice (BR) but its nutritive value has been hardly studied. Since nutritive quality of GBR depends on genetic diversity and germination conditions, six Ecuadorian BR varieties were germinated at 28 and 34 ºC for 48 and 96 h in darkness and proximate composition, dietary fiber fractions, phytic acid content as well as degree of protein hydrolysis and peptide content were studied. Protein, lipids, ash and available carbohydrate ranged 7.3-10.4%, 2.0-4.0%, 0.8-1.5% and 71.6 to 84.0%, respectively, in GBR seedlings. Total dietary fiber increased during germination (6.1-13.6%), with a large proportion of insoluble fraction, while phytic acid was reduced noticeably. In general, protein hydrolysis occurred during germination was more accused at 28 ºC for 48 h. These results suggest that GBR can be consumed directly as nutritive staple food for a large population worldwide contributing to their nutritional requirements.

  14. A systematic study of chemogenomics of carbohydrates.

    PubMed

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

    2014-03-01

    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.

  15. [Functionalized Metal Chelates Based on Diethylenetriaminetetraacetic Acids for Chemical Modification of Proteins and Small Biomolecules].

    PubMed

    Kuprienko, O S; Dubovskaya, L V; Shabunya, P S; Fatykhava, S A; Sviridov, O V

    2015-01-01

    Bifunctional reagents based on diethylenetriaminetetraacetic acid containing a bound metal ion and a reactive functional group for the interaction with proteins and low-molecular-weight substances have been synthesized. An Amino-derivative of a complexonate was obtained by acylation of monosubstituted diamine with diethylenetriaminepentaacetic acid dianhydride followed by deprotection ofthe amino group, purification by anion exchange chromatography and chelation of Eu3+. This metal chelate derivative was used for labeling 17α-hydroxyprogesterone 3-(O-carboxymethyl)oxime and horseradish peroxidase. The enzyme modified with the Eu3+ complexonate at the carbohydrate component and with a cortisol derivative at the polypeptide chain was used in a dissociation-enhanced lanthanide fluorescent immunoassay (DELFIA) as well as in an enzyme immunoassay of the steroid hormone. DELFIA showed that labeled 17α-hydroxyprogesterone retained the affinity for corresponding antibodies. A Eu(3+)-complexonate carboxy-derivative N-succinimide ester was obtained by acylation of the aminochelate with p-phthalic acid di-N-succinimide ester. It was used for modification of amino groups of lysine residues in polypeptide chains of human serum albumin and some immunoglobulins G. Purification of Eu3+ complexonate-protein conjugates by gel-chromatography on a Superose- 12 column allowed to separate the modified proteins from unreacted low molecular weight Eu(3+)-derivatives and to determine a degree of lanthanide inclusion into a protein. The amount of Eu3+ covalently attached to a protein was determined by measuring the fluorescence of a conjugate in the dissociative-enhancement solution. The obtained values correlated well with the results of ICP-MS determination of Eu3+ concentration in a conjugate solution. It was shown that conjugates of monoclonal antibodies obtained by the proposed method possessed the required characteristics of fluorescence intensity, signal-to-noise ratio, sensitivity

  16. Molecular recognition of surface-immobilized carbohydrates by a synthetic lectin.

    PubMed

    Rauschenberg, Melanie; Fritz, Eva-Corrina; Schulz, Christian; Kaufmann, Tobias; Ravoo, Bart Jan

    2014-01-01

    The molecular recognition of carbohydrates and proteins mediates a wide range of physiological processes and the development of synthetic carbohydrate receptors ("synthetic lectins") constitutes a key advance in biomedical technology. In this article we report a synthetic lectin that selectively binds to carbohydrates immobilized in a molecular monolayer. Inspired by our previous work, we prepared a fluorescently labeled synthetic lectin consisting of a cyclic dimer of the tripeptide Cys-His-Cys, which forms spontaneously by air oxidation of the monomer. Amine-tethered derivatives of N-acetylneuraminic acid (NANA), β-D-galactose, β-D-glucose and α-D-mannose were microcontact printed on epoxide-terminated self-assembled monolayers. Successive prints resulted in simple microarrays of two carbohydrates. The selectivity of the synthetic lectin was investigated by incubation on the immobilized carbohydrates. Selective binding of the synthetic lectin to immobilized NANA and β-D-galactose was observed by fluorescence microscopy. The selectivity and affinity of the synthetic lectin was screened in competition experiments. In addition, the carbohydrate binding of the synthetic lectin was compared with the carbohydrate binding of the lectins concanavalin A and peanut agglutinin. It was found that the printed carbohydrates retain their characteristic selectivity towards the synthetic and natural lectins and that the recognition of synthetic and natural lectins is strictly orthogonal.

  17. Effect of jasmonic acid-methyl ester on the composition of carbohydrates and germination of yellow lupine (Lupinus luteus L.) seeds.

    PubMed

    Zalewski, Kazimierz; Nitkiewicz, Bartosz; Lahuta, Lesław B; Głowacka, Katarzyna; Socha, Aleksander; Amarowicz, Ryszard

    2010-08-15

    Mature seeds of yellow lupine contained sucrose, raffinose family oligosaccharides (RFOs), and galactosyl cyclitols as major soluble carbohydrates. The study showed that RFOs dominated in lupine seeds (16% DW). The disappearance of both types of alpha-d-galactosides in germinating lupine seeds was strongly inhibited by the presence of jasmonic acid-methyl ester (JA-Me) at a concentration of 10(-3)M in the incubation medium. JA-Me inhibited the activity of alpha-D-galactosidase (fraction I) during seed germination. Anatomical studies of lupine roots have shown certain cell structure differences between control and JA-Me-treated seedlings. The cross-sections of plant roots treated with JA-Me showed a characteristic folding of the cell walls in all root tissues, starting from the rhyzodermis, cortex and vascular cylinder. In water-treated (control) plants, the cell walls were rounded with no folding.

  18. Analysis of proteins responsive to acetic acid in Acetobacter: molecular mechanisms conferring acetic acid resistance in acetic acid bacteria.

    PubMed

    Nakano, Shigeru; Fukaya, Masahiro

    2008-06-30

    Acetic acid bacteria are used for industrial vinegar production because of their remarkable ability to oxidize ethanol and high resistance to acetic acid. Although several molecular machineries responsible for acetic acid resistance in acetic acid bacteria have been reported, the entire mechanism that confers acetic acid resistance has not been completely understood. One of the promising methods to elucidate the entire mechanism is global analysis of proteins responsive to acetic acid by two-dimensional gel electrophoresis. Recently, two proteins whose production was greatly enhanced by acetic acid in Acetobacter aceti were identified to be aconitase and a putative ABC-transporter, respectively; furthermore, overexpression or disruption of the genes encoding these proteins affected acetic acid resistance in A. aceti, indicating that these proteins are involved in acetic acid resistance. Overexpression of each gene increased acetic acid resistance in Acetobacter, which resulted in an improvement in the productivity of acetic acid fermentation. Taken together, the results of the proteomic analysis and those of previous studies indicate that acetic acid resistance in acetic acid bacteria is conferred by several mechanisms. These findings also provide a clue to breed a strain having high resistance to acetic acid for vinegar fermentation.

  19. Avian serum. cap alpha. /sub 1/-glycoprotein, hemopexin, differing significantly in both amino acid and carbohydrate composition from mammalian (. beta. -glycoprotein) counter parts

    SciTech Connect

    Goldfarb, V.; Trimble, R.B.; Falco, M.D.; Liem, H.H.; Metcalfe, S.A.; Wellner, D.; Muller-Eberhard, U.

    1986-10-21

    The physicochemical characteristics of chicken hemopexin, which can be isolated by heme-agarose affinity chromatography, is compared with representative mammalian hemopexins of rat, rabbit, and human. The avian polypeptide chain appears to be slightly longer (52 kDa) than the human, rat, or rabbit forms (49 kDa), and also the glycoprotein differs from the mammalian hemopexins in being an ..cap alpha../sub 1/-glycoprotein instead of a ..beta../sub 1/-glycoprotein. The distinct electrophoretic mobility probably arises from significant differences in the amino acid composition of the chicken form, which, although lower in serine and particularly in lysine, has a much higher glutamine/glutamate and agrinine content, and also a higher proline, glycine, and histidine content, than the mammalian hemopexins. Compositional analyses and /sup 125/I concanavalin A and /sup 125/I wheat germ agglutinin binding suggest that chicken hemopexin has a mixture of three fucose-free N-linked bi- and triantennary oligosaccharides. In contrast, human hemopexin has give N-linked oligosaccharides and an additional O-linked glycan blocking the N-terminal threonine residue, while the rabbit form has four N-linked oligosaccharides. In keeping with the finding of a simpler carbohydrate structure, the avian hemopexin shows only a single band on polyacrylamide gel electrophoresis under both nondenaturing and denaturing conditions, whereas the hemopexins of the three mammalian species tested show several bands. In contrast, the isoelectric focusing pattern of chicken hemopexin is very complex, revealing at least nine bands between pH 4.0 and pH band 5.0, while the other hemopexins show a broad smear of multiple ill-defined bands in the same region.Results indicate the hemopexin of avians differs substantially from the hemopexins of mammals, which show a notable similarity with regard to carbohydrate structure and amino acid composition.

  20. Highlighting the role of polymer length, carbohydrate size, and nucleic acid type in potency of glycopolycation agents for pDNA and siRNA delivery.

    PubMed

    Xue, Lian; Ingle, Nilesh P; Reineke, Theresa M

    2013-11-11

    While nucleic acids such as small interfering RNA (siRNA) and plasmid DNA (pDNA) are promising research tools and therapeutic modalities, their potential in medical applications is limited by a fundamental mechanistic understanding and inadequate efficiency. Herein, two series of carbohydrate-based polycations were synthesized and examined that varied in the degree of polymerization (n), one containing trehalose [Tr4(n) series: Tr4(23), Tr4(55), Tr4(77)] and the other containing β-cyclodextrin [CD4(n) series: CD4(10), CD4(26), CD4(39), CD4(143), CD4(239)]. In addition, two monosaccharide models were examined for comparison that contain tartaramidoamine (T4) and galactaramidoamine (G4 or Glycofect) repeats. Delivery profiles for pDNA were compared with those obtained for siRNA delivery and reveal that efficacy differs significantly as a function of carbohydrate type, nucleic acid type and dose, polymer length, and presence of excess polymer in the formulation. The Tr4 polymers yielded higher efficacy for pDNA delivery, yet the CD4 polymers achieved higher siRNA delivery and gene down-regulation. The T4 and Glycofect derivatives, while efficient for pDNA delivery, were completely ineffective for siRNA delivery. A strong polymer length and dose dependence on target gene knockdown was observed for all polymers tested. Also, free polymer in solution (uncomplexed) was demonstrated to be a key factor in promoting siRNA uptake and gene down-regulation. PMID:24028685

  1. Highlighting the Role of Polymer Length, Carbohydrate Size, and Nucleic Acid Type in Potency of Glycopolycation Agents for pDNA and siRNA Delivery

    PubMed Central

    Xue, Lian; Ingle, Nilesh P.; Reineke, Theresa M.

    2013-01-01

    While nucleic acids such as small interfering RNA (siRNA) and plasmid DNA (pDNA) are promising research tools and therapeutic modalities, their potential in medical applications is limited by a fundamental mechanistic understanding and inadequate efficiency. Herein, two series of carbohydrate-based polycations were synthesized and examined that varied in the degree of polymerization (n)—one containing trehalose [Tr4(n) series: Tr4(23), Tr4(55), Tr4(77)] and the other containing beta-cyclodextrin [CD4(n) series: CD4(10), CD4(26), CD4(39), CD4(143), CD4(239)]. In addition, two monosaccharide models were examined for comparison that contain tartaramidoamine (T4) and galactaramidoamine (G4 or Glycofect) repeats. Delivery profiles for pDNA were compared with those obtained for siRNA delivery and reveal that efficacy differs significantly as a function of carbohydrate type, nucleic acid type and dose, polymer length, and presence of excess polymer in the formulation. The Tr4 polymers yielded higher efficacy for pDNA delivery, yet, the CD4 polymers achieved higher siRNA delivery and gene down regulation. The T4 and Glycofect derivatives, while efficient for pDNA delivery, were completely ineffective for siRNA delivery. A strong polymer length and dose dependence on target gene knockdown was observed for all polymers tested. Also, free polymer in solution (uncomplexed) was demonstrated to be a key factor in promoting siRNA uptake and gene down regulation. PMID:24028685

  2. Carbohydrate–Aromatic Interactions in Proteins

    PubMed Central

    2015-01-01

    Protein–carbohydrate interactions play pivotal roles in health and disease. However, defining and manipulating these interactions has been hindered by an incomplete understanding of the underlying fundamental forces. To elucidate common and discriminating features in carbohydrate recognition, we have analyzed quantitatively X-ray crystal structures of proteins with noncovalently bound carbohydrates. Within the carbohydrate-binding pockets, aliphatic hydrophobic residues are disfavored, whereas aromatic side chains are enriched. The greatest preference is for tryptophan with an increased prevalence of 9-fold. Variations in the spatial orientation of amino acids around different monosaccharides indicate specific carbohydrate C–H bonds interact preferentially with aromatic residues. These preferences are consistent with the electronic properties of both the carbohydrate C–H bonds and the aromatic residues. Those carbohydrates that present patches of electropositive saccharide C–H bonds engage more often in CH−π interactions involving electron-rich aromatic partners. These electronic effects are also manifested when carbohydrate–aromatic interactions are monitored in solution: NMR analysis indicates that indole favorably binds to electron-poor C–H bonds of model carbohydrates, and a clear linear free energy relationships with substituted indoles supports the importance of complementary electronic effects in driving protein–carbohydrate interactions. Together, our data indicate that electrostatic and electronic complementarity between carbohydrates and aromatic residues play key roles in driving protein–carbohydrate complexation. Moreover, these weak noncovalent interactions influence which saccharide residues bind to proteins, and how they are positioned within carbohydrate-binding sites. PMID:26561965

  3. Radiofluorinated carbohydrates for positron emission tomography.

    PubMed

    Mun, Jiyoung

    2013-01-01

    2-Deoxy-2-[(18)F]fluoro-D-glucose (2-(18)FDG) has represented radiofluorinated carbohydrates as the most successful tracer for positron emission tomography (PET). 2-(18)FDG uptake depends on glucose metabolism, which is related to a disease progression. 2-(18)FDG has been widely used in oncology, neurology, cardiology, infectious diseases, and inflammation, to complement anatomical modalities such as CT and MRI. Followed by the success of 2-(18)FDG, various radiofluorinated carbohydrates have been evaluated as PET tracers, which include analogs of D-ribose, D-mannose, D-galactose, D-talose, D-fructose, D-allose, lactose, L-fucose, N-acetylneuraminic acid, and L-ascorbic acid. Among those radiofluorinated carbohydrates, several have implied potential for further development. 2-Deoxy-2-[(18)F]fluoro-D-galactose has been developed to assess liver function and diagnose hepatic carcinoma. 6-Deoxy-6-[(18)F]fluoro-D-fructose showed promising characteristics for diagnosis of breast cancer. Three radiofluorinated analogs of lactose have been designed as the substrates of the overexpressed hepatocarcinoma-intestine-pancreas/pancreatitis-associated protein in peritumoral pancreatic tissue for early diagnosis of pancreatic cancer. The metabolism of 6-[(18)F]fluoro-L-fucose suggested that it is a bioactive analog of L-fucose in the synthesis of glycoconjugate macromolecules. 6-Deoxy-6-[(18)F]fluoro-L-ascorbic acid was evaluated to assess antioxidant function of L-ascorbic acid in rodent models of transient global ischemia and glutathione deficiency.

  4. Comparative proteomic analysis of oil palm leaves infected with Ganoderma boninense revealed changes in proteins involved in photosynthesis, carbohydrate metabolism, and immunity and defense.

    PubMed

    Jeffery Daim, Leona Daniela; Ooi, Tony Eng Keong; Ithnin, Nalisha; Mohd Yusof, Hirzun; Kulaveerasingam, Harikrishna; Abdul Majid, Nazia; Karsani, Saiful Anuar

    2015-08-01

    The basidiomycete fungal pathogen Ganoderma boninense is the causative agent for the incurable basal stem rot (BSR) disease in oil palm. This disease causes significant annual crop losses in the oil palm industry. Currently, there is no effective method for disease control and elimination, nor is any molecular marker for early detection of the disease available. An understanding of how BSR affects protein expression in plants may help identify and/or assist in the development of an early detection protocol. Although the mode of infection of BSR disease is primarily via the root system, defense-related genes have been shown to be expressed in both the root and leafs. Thus, to provide an insight into the changes in the global protein expression profile in infected plants, comparative 2DE was performed on leaf tissues sampled from palms with and without artificial inoculation of the Ganoderma fungus. Comparative 2DE revealed that 54 protein spots changed in abundance. A total of 51 protein spots were successfully identified by LC-QTOF MS/MS. The majority of these proteins were those involved in photosynthesis, carbohydrate metabolism as well as immunity and defense.

  5. Comparative proteomic analysis of oil palm leaves infected with Ganoderma boninense revealed changes in proteins involved in photosynthesis, carbohydrate metabolism, and immunity and defense.

    PubMed

    Jeffery Daim, Leona Daniela; Ooi, Tony Eng Keong; Ithnin, Nalisha; Mohd Yusof, Hirzun; Kulaveerasingam, Harikrishna; Abdul Majid, Nazia; Karsani, Saiful Anuar

    2015-08-01

    The basidiomycete fungal pathogen Ganoderma boninense is the causative agent for the incurable basal stem rot (BSR) disease in oil palm. This disease causes significant annual crop losses in the oil palm industry. Currently, there is no effective method for disease control and elimination, nor is any molecular marker for early detection of the disease available. An understanding of how BSR affects protein expression in plants may help identify and/or assist in the development of an early detection protocol. Although the mode of infection of BSR disease is primarily via the root system, defense-related genes have been shown to be expressed in both the root and leafs. Thus, to provide an insight into the changes in the global protein expression profile in infected plants, comparative 2DE was performed on leaf tissues sampled from palms with and without artificial inoculation of the Ganoderma fungus. Comparative 2DE revealed that 54 protein spots changed in abundance. A total of 51 protein spots were successfully identified by LC-QTOF MS/MS. The majority of these proteins were those involved in photosynthesis, carbohydrate metabolism as well as immunity and defense. PMID:25930948

  6. Real-time and label-free analysis of binding thermodynamics of carbohydrate-protein interactions on unfixed cancer cell surfaces using a QCM biosensor.

    PubMed

    Li, Xueming; Song, Siyu; Shuai, Qi; Pei, Yihan; Aastrup, Teodor; Pei, Yuxin; Pei, Zhichao

    2015-01-01

    A novel approach to the study of binding thermodynamics and kinetics of carbohydrate-protein interactions on unfixed cancer cell surfaces using a quartz crystal microbalance (QCM) biosensor was developed, in which binding events take place at the cell surface, more closely mimicking a biologically relevant environment. In this study, colon adenocarcinoma cells (KM-12) and ovary adenocarcinoma cells (SKOV-3) grew on the optimized polystyrene-coated biosensor chip without fixation. The association and dissociation between the cell surface carbohydrates and a range of lectins, including WGA, Con A, UEA-I, GS-II, PNA and SBA, were monitored in real time and without label for evaluation of cell surface glycosylation. Furthermore, the thermodynamic and kinetic parameters of the interaction between lectins and cell surface glycan were studied, providing detailed information about the interactions, such as the association rate constant, dissociation rate constant, affinity constant, as well as the changes of entropy, enthalpy and Gibbs free energy. This application provides an insight into the cell surface glycosylation and the complex molecular recognition on the intact cell surface, which may have impacts on disease diagnosis and drug discovery.

  7. Biologically-Inspired Peptide Reagents for Enhancing IMS-MS Analysis of Carbohydrates

    NASA Astrophysics Data System (ADS)

    Bohrer, Brian C.; Clemmer, David E.

    2011-09-01

    The binding properties of a peptidoglycan recognition protein are translated via combinatorial chemistry into short peptides. Non-adjacent histidine, tyrosine, and arginine residues in the protein's binding cleft that associate specifically with the glycan moiety of a peptidoglycan substrate are incorporated into linear sequences creating a library of 27 candidate tripeptide reagents (three possible residues permutated across three positions). Upon electrospraying the peptide library and carbohydrate mixtures, some noncovalent complexes are observed. The binding efficiencies of the peptides vary according to their amino acid composition as well as the disaccharide linkage and carbohydrate ring-type. In addition to providing a charge-carrier for the carbohydrate, peptide reagents can also be used to differentiate carbohydrate isomers by ion mobility spectrometry. The utility of these peptide reagents as a means of enhancing ion mobility analysis of carbohydrates is illustrated by examining four glucose-containing disaccharide isomers, including a pair that is not resolved by ion mobility alone. The specificity and stoichiometry of the peptide-carbohydrate complexes are also investigated. Trihistidine demonstrates both suitable binding efficiency and successful resolution of disaccharides isomers, suggesting it may be a useful reagent in IMS analyses of carbohydrates.

  8. Validation of extrusion as a killing step for Enterococcus faecium in a balanced carbohydrate-protein meal by using a response surface design.

    PubMed

    Bianchini, Andreia; Stratton, Jayne; Weier, Steve; Hartter, Timothy; Plattner, Brian; Rokey, Galen; Hertzel, Gerry; Gompa, Lakshmi; Martinez, Bismarck; Eskridge, Andkent M

    2012-09-01

    Outbreaks of salmonellosis and recalls of low-moisture foods including extruded products highlight the need for the food and feed industries to validate their extrusion processes to ensure the destruction of pathogenic microorganisms. Response surface methodology was employed to study the effect of moisture and temperature on inactivation by extrusion of Enterococcus faecium NRRL B-2354 in a carbohydrate-protein mix. A balanced carbohydrate-protein mix was formulated to different combinations of moisture contents, ranging from 24.9 to 31.1%, and each was inoculated with a pure culture of E. faecium to a final level of 5 log CFU/g. Each mix of various moistures was then extruded in a pilot scale extruder at different temperatures (ranging from 67.5 to 85°C). After the extruder was allowed to equilibrate for 10 min, samples were collected in sterile bags, cooled in dry ice, and stored at 4°C prior to analysis. E. faecium was enumerated with tryptic soy agar and membrane Enterococcus media, followed by incubation at 35°C for 48 h. Each extrusion was repeated twice, with the central point of the design being repeated four times. From each extrusion, three subsamples were collected for microbial counts and moisture determination. Based on the results, the response surface model was y = 185.04 - 3.11X(1) - 4.23X(2) + 0.02X(1)(2) - 0.004X(1)X(2) + 0.08X(2)(2), with a good fit (R(2) = 0.92), which demonstrated the effects of moisture and temperature on the inactivation of E. faecium during extrusion. According to the response surface analysis, the greatest reduction of E. faecium for the inoculation levels studied here (about 5 log) in a carbohydrate-protein meal would occur at the temperature of 81.1°C and moisture content of 28.1%. Other temperature and moisture combinations needed to achieve specific log reductions were plotted in a three-dimensional response surface graph.

  9. Intravenous or luminal amino acids are insufficient to maintain pancreatic growth and digestive enzyme expression in the absence of intact dietary protein

    PubMed Central

    Baumler, Megan D.; Koopmann, Matthew C.; Thomas, Diana D. H.; Ney, Denise M.

    2010-01-01

    We previously reported that rats receiving total parenteral nutrition (TPN) undergo significant pancreatic atrophy characterized by reduced total protein and digestive enzyme expression due to a lack of intestinal stimulation by nutrients (Baumler MD, Nelson DW, Ney DM, Groblewski GE. Am J Physiol Gastrointest Liver Physiol 292: G857–G866, 2007). Essentially identical results were recently reported in mice fed protein-free diets (Crozier SJ, D'Alecy LG, Ernst SA, Ginsburg LE, Williams JA. Gastroenterology 137: 1093–1101, 2009), provoking the question of whether reductions in pancreatic protein and digestive enzyme expression could be prevented by providing amino acids orally or by intravenous (IV) infusion while maintaining intestinal stimulation with fat and carbohydrate. Controlled studies were conducted in rats with IV catheters including orally fed/saline infusion or TPN-fed control rats compared with rats fed a protein-free diet, oral amino acid, or IV amino acid feeding, all with oral carbohydrate and fat. Interestingly, neither oral nor IV amino acids were sufficient to prevent the pancreatic atrophy seen for TPN controls or protein-free diets. Oral and IV amino acids partially attenuated the 75–90% reductions in pancreatic amylase and trypsinogen expression; however, values remained 50% lower than orally fed control rats. Lipase expression was more modestly reduced by a lack of dietary protein but did respond to IV amino acids. In comparison, chymotrypsinogen expression was induced nearly twofold in TPN animals but was not altered in other experimental groups compared with oral control animals. In contrast to pancreas, protein-free diets had no detectable effects on jejunal mucosal villus height, total mass, protein, DNA, or sucrase activity. These data underscore that, in the rat, intact dietary protein is essential in maintaining pancreatic growth and digestive enzyme adaptation but has surprisingly little effect on small intestinal mucosa. PMID

  10. Protein and amino acid metabolism in the human newborn.

    PubMed

    Kalhan, Satish C; Bier, Dennis M

    2008-01-01

    Birth and adaptation to extrauterine life involve major shifts in the protein and energy metabolism of the human newborn. These include a shift from a state of continuous supply of nutrients including amino acids from the mother to cyclic periodic oral intake, a change in the redox state of organs, thermogenesis, and a significant change in the mobilization and use of oxidative substrates. The development of safe, stable isotopic tracer methods has allowed the study of protein and amino acid metabolism not only in the healthy newborn but also in those born prematurely and of low birth weight. These studies have identified the unique and quantitative aspects of amino acid/protein metabolism in the neonate, thus contributing to rational nutritional care of these babies. The present review summarizes the contemporary data on some of the significant developments in essential and dispensable amino acids and their relationship to overall protein metabolism. Specifically, the recent data of kinetics of leucine, phenylalanine, glutamine, sulfur amino acid, and threonine and their relation to whole-body protein turnover are presented. Finally, the physiological rationale and the impact of nutrient (amino acids) interventions on the dynamics of protein metabolism are discussed.

  11. Fatty acid transfer between multilamellar liposomes and fatty acid-binding proteins.

    PubMed

    Brecher, P; Saouaf, R; Sugarman, J M; Eisenberg, D; LaRosa, K

    1984-11-10

    A simple experimental system was developed for studying the movement of long-chain fatty acids between multilamellar liposomes and soluble proteins capable of binding fatty acids. Oleic acid was incorporated into multilamellar liposomes containing cholesterol and egg yolk lecithin and incubated with albumin or hepatic fatty acid-binding protein. It was found that the fatty acid transferred from the liposomes to either protein rapidly and selectively under conditions where phospholipid and cholesterol transfer did not occur. More than 50% of the fatty acid contained within liposomes could become protein bound, suggesting that the fatty acid moved readily between and across phospholipid bilayers. Transfer was reduced at low pH, and this reduction appeared to result from decreased dissociation of the protonated fatty acid from the bilayer. Liposomes made with dimyristoyl or dipalmitoyl lecithin and containing 1 mol per cent palmitic acid were used to show the effect of temperature on fatty acid transfer. Transfer to either protein did not occur at temperatures where the liposomes were in a gel state but occurred rapidly at temperatures at or above the transition temperatures of the phospholipid used. PMID:6490659

  12. Blood pressure decreases more after high-carbohydrate meals than after high-protein meals in overweight adults with elevated blood pressure, but there is no difference after 4 weeks of consuming a carbohydrate-rich or protein-rich diet.

    PubMed

    Teunissen-Beekman, Karianna F M; Dopheide, Janneke; Geleijnse, Johanna M; Bakker, Stephan J L; Brink, Elizabeth J; de Leeuw, Peter W; Serroyen, Jan; van Baak, Marleen A

    2013-04-01

    The replacement of dietary carbohydrates with proteins can lower blood pressure (BP), but the mechanisms remain unclear. This randomized, double-blind, parallel-group study aimed to compare 12-h postprandial sympathetic and hemodynamic responses after high-protein (HP) meals and high-carbohydrate (HC) meals. Fifty-two men and women with untreated elevated BP were tested on d 1 and after 4 wk of supplementation [3 × 20 g protein (HP) or maltodextrin (HC) per day]. No between-group differences were found in postprandial plasma norepinephrine on d 1 and at wk 4. On d 1, postprandial mean arterial pressure (MAP) decreased more in the HC group than in the HP group (P = 0.002). This difference was not present at 4 wk, because the postprandial decline in MAP tended to become larger in the HP group after 4 wk of supplementation (P = 0.07). On both test days, postprandial total peripheral resistance tended to decrease more in the HC group (P < 0.08). After 4 wk of supplementation, cardiac output tended to increase more in the HC group (P = 0.08). In conclusion, ingestion of an HP diet induced a smaller decrease in BP on d 1 than did ingestion of an HC diet. This difference disappeared after 4 wk due to a more pronounced decrease in BP in the HP group after 4 wk than on d 1. These findings cannot explain the BP-lowering effect ascribed to dietary proteins.

  13. Conformational Entropy of Intrinsically Disordered Proteins from Amino Acid Triads

    PubMed Central

    Baruah, Anupaul; Rani, Pooja; Biswas, Parbati

    2015-01-01

    This work quantitatively characterizes intrinsic disorder in proteins in terms of sequence composition and backbone conformational entropy. Analysis of the normalized relative composition of the amino acid triads highlights a distinct boundary between globular and disordered proteins. The conformational entropy is calculated from the dihedral angles of the middle amino acid in the amino acid triad for the conformational ensemble of the globular, partially and completely disordered proteins relative to the non-redundant database. Both Monte Carlo (MC) and Molecular Dynamics (MD) simulations are used to characterize the conformational ensemble of the representative proteins of each group. The results show that the globular proteins span approximately half of the allowed conformational states in the Ramachandran space, while the amino acid triads in disordered proteins sample the entire range of the allowed dihedral angle space following Flory’s isolated-pair hypothesis. Therefore, only the sequence information in terms of the relative amino acid triad composition may be sufficient to predict protein disorder and the backbone conformational entropy, even in the absence of well-defined structure. The predicted entropies are found to agree with those calculated using mutual information expansion and the histogram method. PMID:26138206