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Статті в журналах з теми "Sucres amines":

1

Thomas, Aleena, Baptiste Gasch, Enzo Olivieri, and Adrien Quintard. "Trichloroacetic acid fueled practical amine purifications." Beilstein Journal of Organic Chemistry 18 (February 24, 2022): 225–31. http://dx.doi.org/10.3762/bjoc.18.26.

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Amine purification have for long been dominated by tedious stepwise processes involving the generation of large amounts of undesired waste. Inspired by recent work on out of equilibrium molecular machinery, using trichloroacetic acid (TCA), we disclose a purification technique considerably decreasing the number of operations and the waste generation required for such purifications. At first, TCA triggers the precipitation of the amines through their protonated salt formation, enabling the separation with the impurities. From these amine salts, simple decarboxylation of TCA liberates volatile CO2 and chloroform affording directly the pure amines. Through this approach, a broad range of diversely substituted amines could be isolated with success.
2

Ding, Wen, Shaoyu Mai, and Qiuling Song. "Molecular-oxygen-promoted Cu-catalyzed oxidative direct amidation of nonactivated carboxylic acids with azoles." Beilstein Journal of Organic Chemistry 11 (November 11, 2015): 2158–65. http://dx.doi.org/10.3762/bjoc.11.233.

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A copper-catalyzed oxidative direct formation of amides from nonactivated carboxylic acids and azoles with dioxygen as an activating reagent is reported. The azole amides were produced in good to excellent yields with a broad substrate scope. The mechanistic studies reveal that oxygen plays an essential role in the success of the amidation reactions with copper peroxycarboxylate as the key intermediate. Transamidation occurs smoothly between azole amide and a variety of amines.
3

Rahman, N. A., W. Widiyastuti, and S. P. A. Anggraini. "FUNCTIONALIZATION OF SILICA FROM BAGASSE ASH WITH PRIMARY AMINES: FTIR ANALYSIS." RASAYAN Journal of Chemistry 15, no. 02 (2022): 885–88. http://dx.doi.org/10.31788/rjc.2022.1526177.

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Organic silica from bagasse ash was successfully manufactured as a carbon dioxide gas adsorbent. Moreover, this is accomplished by functionalizing the silica surface's amine groups. Amines have high reactivity to CO2 gas. Using the in-situ method, silanol groups can interact with amine groups. This research employs an in-situ technique in which the hydrolysis and condensation reactions co-occur to form a gel. Infrared spectroscopy was used to assess the efficacy of the functionalization of silanol and amine groups. This work aimed to examine the success of the functionalization of the amine group on the silica surface using infrared spectroscopy to produce carbon dioxide gas as an adsorbent. Fourier-Transform Infrared (FTIR) spectroscopy indicated a shift in silica groups produced by amine functionalization.
4

Still, Ian WJ, Rosanne Natividad-Preyra, and F. Dean Toste. "A versatile synthetic route to 1,5-dithiocins from o-mercapto aromatic aldehydes." Canadian Journal of Chemistry 77, no. 1 (January 1, 1999): 113–21. http://dx.doi.org/10.1139/v98-230.

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An earlier procedure for the facile preparation of benzo-fused 1,5-dithiocins 2a-2c from o-mercapto- benzaldehydes has been improved and shown to be capable of extension to the preparation of several naphthalene-derived analogues. The general method also afforded several N-alkylated 1,5-dithiocins 4, 5 by replacing NH3 with the appropriate primary amine. It was found that N-acylation of the 1,5-dithiocins was successful only with methyl chloroformate. Attempted N-phenylation met with limited success but was shown to be unnecessary since even the less reactive aniline readily undergoes the general reaction of primary amines. When simple α-amino acids, or their methyl esters, were employed as the primary amine in the reaction with o-mercaptobenzaldehyde, the formation of the N-alkylated 1,5-dithiocins 4a, 17a,17b with accompanying loss of -COOH or -COOMe was observed, in preparatively useful yields. A mechanism is proposed for this interesting transformation.Key words: 1,5-dithiocins, α-amino acids, N-acylation, decarboxylation.
5

Roura Padrosa, David, Zoya Nisar, and Francesca Paradisi. "Efficient Amino Donor Recycling in Amination Reactions: Development of a New Alanine Dehydrogenase in Continuous Flow and Dialysis Membrane Reactors." Catalysts 11, no. 4 (April 20, 2021): 520. http://dx.doi.org/10.3390/catal11040520.

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Transaminases have arisen as one of the main biocatalysts for amine production but despite their many advantages, their stability is still a concern for widespread application. One of the reasons for their instability is the need to use an excess of the amino donor when trying to synthesise amines with unfavourable equilibria. To circumvent this, recycling systems for the amino donor, such as amino acid dehydrogenases or aldolases, have proved useful to push the equilibria while avoiding high amino donor concentrations. In this work, we report the use of a new alanine dehydrogenase from the halotolerant bacteria Halomonas elongata which exhibits excellent stability to different cosolvents, combined with the well characterised CbFDH as a recycling system of L-alanine for the amination of three model substrates with unfavourable equilibria. In a step forward, the amino donor recycling system has been co-immobilised and used in flow with success as well as re-used as a dialysis enclosed system for the amination of an aromatic aldehyde.
6

Novak, Levente, Muriel Cocaign-Bousquet, Nicholas D. Lindley, and Pascal Loubière. "Cométabolisme sucre-acides aminés chez Lactococcus lactis." Le Lait 78, no. 1 (1998): 17–22. http://dx.doi.org/10.1051/lait:199813.

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7

Niephaus, Herbert, Gerhard Raabe, and Jörg Fleischhauer. "Quantenchemische Rechnungen an Stickstoffbasen. Teil 4*: Zur Berechnung der Polarisierbarkeiten aliphatischer Amine mit der MINDO /3-FP-Methode." Zeitschrift für Naturforschung A 41, no. 4 (April 1, 1986): 671–77. http://dx.doi.org/10.1515/zna-1986-0413.

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The polarizabilities of some primary, secondary, and tertiary amines have been calculated with the MINDO/3-FP-method. The calculated values are found to correlate with the experimental polarizabilities and with those determined by the method of Miller and Savchik in a satisfying manner. In addition atomic polarizabilities have been calculated according to the method of Metzger. Averaging over the calculated mean atomic polarizabilities of hydrogen, carbon, and nitrogen yields increments which, when used to recalculate molecular polarizabilities, lead to values which correlate in an excellent manner with those determined from densities and refraction indices by means of the Lorenz-Lorentz-equation.Because different nitrogen increments have been determined for primary, secondary and tertiary amines, the parameters presented here make it possible to distinguish between constitutional isomers as long as they belong to different groups (i.e. primary, secondary, and tertiary amines), something which cannot be done using the method of Miller and Savchik. The increments derived do not only allow to predict the polarizabilities of primary, secondary and tertiary amines but can be used to calculate the corresponding values for hydrazines and polyfunctional amines with equal success.
8

Liu, Jingjing, Jiaxi Xu, Zhenjiang Li, Songquan Xu, Xin Wang, Haixin Wang, Tianfo Guo, Yu Gao, Lei Zhang, and Kai Guo. "Squaramide and amine binary H-bond organocatalysis in polymerizations of cyclic carbonates, lactones, and lactides." Polymer Chemistry 8, no. 45 (2017): 7054–68. http://dx.doi.org/10.1039/c7py01671a.

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9

Régaldo-Saint-Blancard, Pierre. "Les céramiques de raffinage du sucre : typologie - technologie." Archéologie du Midi médiéval 4, no. 1 (1986): 151–68. http://dx.doi.org/10.3406/amime.1986.1125.

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10

Lin, Cheng, Hui Yun Zhang, Xiao Ying Lin, and Yun Fei Feng. "Adsorption CO2 on Activated Carbon with Surface Modification." Advanced Materials Research 634-638 (January 2013): 746–50. http://dx.doi.org/10.4028/www.scientific.net/amr.634-638.746.

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The success of CO2 capture from flue gas with solid sorbent is dependent of a low cost sorbent with high CO2 adsorption capacity and selectivity. Modifying surface texture of activated carbon with impregnating amines is expected to offer the benefits of liquid amines in the typical adsorption process routes. In this work, cocoanut activate carbon (AC) is firstly alkalified by KOH solution, then modified by impregnation of tetraethylenepentamine (TEPA), triethylenetetramine (TATA), and triethanolamine (TEA) to form a new type of sorbents. The effects of alkalifying treatment and temperature on CO2 adsorption capacities of the sorbents are investigated. Results indicate that the activate carbons modified by combining alkalification pretreatment firstly and then impregnated amines at low temperature are profitable for CO2 adsorption. The adsorption capacities of CO2 are enhanced with TEPA and TETA impregnation on the activate carbon pretreated by KOH solution. And CO2 adsorption capacity of new sorbents is stable after many adsorption and desorption cycles.

Дисертації з теми "Sucres amines":

1

Branquet, Éric. "Synthese d'amino sucres et d'acides alpha-amines exotiques a partir d'acides alpha-amines naturels." Paris 6, 1993. http://www.theses.fr/1993PA066521.

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Le pool chiral que represente les acides alpha-amines en synthese organique a fait l'objet de nombreuses applications dans la synthese d'acides amines non usuels, mais peu d'applications dans la synthese des amino sucres ont ete decrites. Sont decrites dans ce rapport: a) une nouvelle approche de synthese de trois-amino-trois-desoxy tetro ou pentofuranosides diversement substitues en position deux et de trois-amino-trois-desoxy, thiofuranosides, a partir de beta-hydroxy ou de beta-thio amino acides naturels. Ces sucres sont des analogues de la partie glycosidique de molecules naturelles tels que les antibiotiques nucleosidiques, les macrolides, les anthracyclines. Une extension a la synthese de quatre-amino-quatre-desoxy hexoses a aussi ete etudiee; b) la synthese enantioselective de l'ethynyl glycine en utilisant un equivalent de l'acide penaldique: le n-terbutyloxycarbonyl serinal acetonide. Parallelement, cette voie de synthese a permis d'acceder a de nouveaux deux-amino-un, trois-dienes diversement substitues en position quatre selon un rearrangement de type klemer-rodemeyer a partir de un, trois-(n, o)-oxazolidines; c) la synthese d'un dipeptide l-phe/acide alpha-amine-beta-gamma-ether d'enol par une isomerisation de type schollkopf
2

Aviles-Moreno, Juan-Ramón. "Flexibilité conformationnelle dans les amines, les sucres et leurs complexes hydratés étudiée par spectroscopie à impulsions microondes et calculs de chimie quantique." Lille 1, 2006. https://ori-nuxeo.univ-lille1.fr/nuxeo/site/esupversions/65353286-2f4b-4a09-9c9a-243841438735.

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En spectroscopie le couplage expérience-théone permet notamment la déterminatIon des structures des conformères les plus stables de (bio)molécules ainsi que l'analyse de mouvements de grande amplitude et de structures hyperfines. Nous avons réalIsé des expériences de spectroscopie à Impulsions mlcroondes par transformée de Fourier en jet supersonique et des calculs de chimie quantique (ab initio et DFT). Nos principaux résultats concernent l'étude de sucres CnH2nOn et de leurs complexes hydratés. Dans le complexe glycolaldéhyde-eau (n=2), la molécule d'eau s'insère avec unc sélectivité au niveau des liaisons hydrogéne en cassant la liaison intramoléculaire et en formant deux lIaisons intermoléculaires. De plus. Nous avons mis en évidence une flexibilité conformationnelle au sein du complexe, modélIsée avec une surface d'énergie potentielle rendant compte des mouvements de grande amplitude des groupes hydroxyles du complexe. Cette étude d intérêt général a été étendue aux complexes hydratés des sucres C3. Par ailleurs, la structure hyperfine spin nucléaire - spin nucléaire des sucres en C2 et C3 (1. 3-dihydroxyacétone) a été observée et modélisée. Ce modèle pourrait être appliqué à tous les sucres CnH2nOn. Enfm, nous avons développé une méthodologie pour caractériser les conformères les plus stables des sucres en C. Pour les amines avec liaison peptidique, nous avons résolu la controverse sur l'énergie relative des conforméres E et Z du N-phénylformamide, avec une méthodologie adaptée. Qui a ensuite été appliquée au benzamide et au complexe urée-eau. La structure hyperfine de la molécule chirale CHCIFI a été caractérisée et sa structure a l'équilibre calculée ab initio.
3

Caparros, Alain. "Valorisation des acides ôméga-aminés : macrocyclisation dans les systèmes organisés et synthèse de bolaformes mixtes anioniques et dérivés de sucres." Toulouse 3, 1996. http://www.theses.fr/1996TOU30051.

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La faible solubilite des acides omega-amines limite considerablement le champs d'application de ces composes dans le domaine de la chimie. Nos travaux ont permis de valoriser ces substrats selon deux axes de recherche: la synthese de macrolactames dans des milieux structures et leur utilisation dans l'elaboration de nouvelles molecules tensioactives de type bolaforme. Comme pour la plupart des macrocycles, la preparation de macrolactames est generalement realisee dans des conditions de haute dilution afin de limiter les reactions de dimerisation et de polymerisation. La cyclisation des acides omega-amines a ete etudiee dans des systemes ternaires constitues de toluene, propane-2-ol et de formamide (ou traces d'eau) en presence de triethylamine. Apres une activation par le reactif de mukayama, l'acide 8-aminocaprylique et de l'acide 12-aminododecanoique ont ete cyclises avec succes sans condition de haute dilution dans ces milieux microemulsion en l'absence de tensioactif. Le substrat se localiserait a l'interface des agregats moleculaires sous une forme precyclisee propice a la reaction intramoleculaire. De meilleurs rendements ont cependant ete observes dans l'obtention de la 2-azacyclotridecanone. Ces resultats semblent correles a des differences de solubilite des precurseurs dans la phase continue. L'extension de ces systemes a la synthese de molecules plus complexes telles que les cyclopeptides s'est revelee tres prometteuse. La 4-ala-chlamydocine, tetrapeptide cyclique, est obtenus avec une selectivite en faveur du cyclomonomere sans condition de haute dilution. Dans l'attente d'experiences visant a controler l'absence de racemisation, le reactif de mukayama se presente comme un agent de couplage tres prometteur pour la cyclisation des peptides. Afin d'etendre le domaine d'utilisation des acides omega-amines, nos investigations se sont orientees vers la synthese de bolaformes anioniques. Deux familles de bolaformes dissymetriques a tete sucre ont ete preparees: les omega-gluconamidoalcanoates de sodium et les omega-lactobionmidoalcanoates de sodium. Ces composes ont ete obtenus avec de tres bons rendements par une methode simple et peu couteuse. Des etudes physicochimiques ont mis en evidence la presence de vesicules de taille monodisperse. Les acides omega-amines ont egalement fait l'objet de synthese de bolaformes anioniques bicatenaires a tete sucre. Ces composes de structure analogue au galactosylceramide, recepteur du virus du sida, semblent prometteurs pour la mise au point de traitements contre le vih
4

Mihai, Simona. "Systèmes biomimétiques multifonctionnels via des interactions cation-π, sucres-protéines et autoassemblages de quartets de guanosine". Montpellier 2, 2009. http://www.theses.fr/2009MON20217.

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Le fonctionnement du monde vivant repose sur des processus de reconnaissance moléculaire entre les différents partenaires. Cette reconnaissance a lieu grâce à diverses interactions faibles non covalentes. Dans le cadre de ce travail de thèse nous nous sommes intéressés aux processus de reconnaissance moléculaire impliquant les chaînes latérales d'aminoacides aromatiques rencontrées dans l'adhésion cellulaire, le transport de divers cations et la reconnaissance de neurotransmetteurs au niveau des synapses du système nerveux central. Nous avons ainsi mis en évidence la compléxation de carbohydrates par des noyaux aromatiques au travers d'interactions CH-pi ainsi que la complexation de divers sels organiques et inorganiques au travers d'interactions cation-pi par ces mêmes récepteurs. Nous avons ainsi réalisé le transport compétitif de neurotransmetteurs au travers d'une membrane hybride alumino-siliciée fonctionnalisée par nos récepteurs synthétiques. D'autre part, nous avons accordé une importance particulière à la superstructure dynamique formée de quartets de guanosine et cherché notamment à observer le transfert de chiralité de cette structure à la matrice inorganique durant un processus sol gel. Nous avons également stabilisé les G-quadruplexes dans un milieu confiné silicié et avons développé une méthode d'encapsulation de principes actifs basée sur la reconnaissance spécifique des G4
The functioning of the living world rests on processes of molecular recognition between the various partners. This recognition takes place thanks to diverse weak interactions not covalentes. Within the framework of this work of thesis we were interested in the processes of molecular recognition involving the side chains of aromatic aminoacides met in the cellular membership, the transport of diverse cations and the recognition of neurotransmitters at the level of the synapses of the central nervous system. We so put in evidence the compléxation of carbohydrates by aromatic nuclei through interactions CH-pi as well as the compléxation of diverse organic and inorganic salts through interactions cation-pi by these same receivers. We so realized the competitive transport of neurotransmitters through a hybrid membrane alumino-siliciée fonctionnalisée by our synthetic receivers. On the other hand, we granted a particular importance for the dynamic superstructure formed by quartets of guanosine and tried in particular to observe the transfer of chirality of this structure in the inorganic matrix during a sol-gel process. We also stabilized G-quadruplexes in a stuffy silicié environment and developed a method of encapsulation of active principles based on the specific recognition of G4
5

Tsafack, Takadong Julie Judith. "Microtubérisation chez Xanthosoma sagittifolium (L. ) Schott (Macabo) et analyse de quelques aspects physiologiques et biochimiques." Brest, 2011. http://www.theses.fr/2011BRES2005.

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Le macabo (Xanthosoma sagittifolium L. Schott, Araceae) est une plante à tubercules à la base de l’alimentation de populations des tropiques. L’induction des tubercules in vitro peut être un moyen efficace pour la propagation de matériel sain et l’augmentation de sa productivité. L’objectif principal de ce travail est de rechercher les conditions optimales pour la production des microtubercules et appréhender les mécanismes physiologiques et biochimiques de la tubérisation chez le macabo. La microtubérisation chez le macabo est influencée par le génotype, la teneur en saccharose, la nutrition azotée, les régulateurs de croissance et les traitements photo et thermopériodiques. Le meilleur rendement est obtenu sur milieu MS à 8% de saccharose et en jours courts de 8h avec thermopériode (25/20°C, jour/nuit) pendant 10 jours, suivis dune obscurité totale (JC1-Obs) à 20°C pendant 50 jours. Comme au champ, le cultivar blanc est plus productif in vitro que les cultivars rouge et jaune. Parmi les régulateurs de croissance testés (BAP, ABA, STS, GA3, ancymidol et flurprimidol), le milieu contenant la BAP à 30 µM augmente significativement le pourcentage de tubérisation. La microtubérisation peut être induite sans régulateur de croissance exogène avec un taux d’explants tubérisés de 70%. Les explants tubérisés (13,8%) peuvent être conservés au moins 8 mois à 25°C, en présence de saccharose (2%) et d’agents osmotiques (mannitol et sorbitol, 2%), en gardant le pouvoir germinatif des microtubercules. Plus de 90% des microtubercules germent et engendrent des vitroplants qui donnent un taux de reprise au champ d’environ 80% après un mois. Les milieux où le rapport NO3-/NH4+ est supérieur à 1, sont les plus favorables à la formation des tubercules et à l’accumulation des sucres solubles. Le milieu G (MG), plus pauvre en azote que le milieu MS, donne un faible pourcentage de tubérisation et réduit néanmoins le taux de repousse en induisant une faible activité a-amylase. L’initiation des tubercules, visibles au jour 10, est caractérisée par une stimulation de l’activité guaiacol-peroxydasique (G-Pox) et l’apparition de nouvelles isoperoxydases. Au cours des premières étapes de la tubérisation, des acides aminés (principalement Ala, Arg, Gln, Glu, Thr et Val) et des protéines s’accumulent, et des polypeptides nouveaux sont mis en évidence. Par ailleurs, l’augmentation du rapport glucose/fructose dans les feuilles parallèlement avec l’augmentation du saccharose et de l’amidon dans les parties basales coïncide avec l’apparition des premiers tubercules. Le saccharose dégradé par les invertases est associé à l’initiation des tubercules et la saccharose synthase assure leur remplissage
Cocoyam (Xanthosoma (L. ) Schott, Araceae) is an important staple tuber crop for tropical populations. In vitro tuber induction could be an effective way to propagate a disease-free material and increase the productivity of valuable cocoyam. The principal objective of this study is to investigate the optimal conditions for microtubers production and to understand the physiological and biochemical mechanisms of cocoyam tuberization. The cocoyam microtuberization is influenced by the genotype, the sucrose level, nitrogen nutrition, plant growth regulators (PGRs), photoperiod and thermoperiod regimes. The best response is obtained on MS medium supplemented with 8% sucrose, under short days of 8 h and with thermoperiod (25/20°C, day/night) for 10 days, followed by a continuous darkness at 20°C for 50 days. As in the field, the white cultivar is more productive than the red and yellow cultivars. Among the PGRs tested (BAP, ABA, STS, GA3, Ancymidol and flurprimidol), the medium with 30 µM 6-benzylaminopurine (BAP) significantly increase the tuberization frequency. Microtuberization can be induced on PGRs free medium with 70% rate of tuberized expiant. The tuberized explants (13. 8%) can be conserved in vitro for at least 8 months at 25°C, in the presence of sucrose (2%) and osmotic agents (mannitol and sorbitol, 2%). More than 90% of microtubers sprout and produce vitroplants that yield 80% of cocoyam plants after one month in the field. The media where the NO3-/NH4+ ratio is higher than 1, are more favourable to tuber formation and soluble carbohydrate accumulation. The G medium, that is poorer in nitrogen than MS medium, gives a low percentage of tuberization and nevertheless reduces the regrowth rate by inducing low a-amylase activity. Tuber initiation observable alter ten days of culture on inductive condition is characterized by a stimulation of the guaiacol-peroxidase activities and the apparition of novel isoperoxidases. During early stages of the microtuberization process, amino acids (mainly Ala, Arg, Gln, Glu, Thr and Val) and proteins accumulate, and novel polypeptides are highlighted. Furthermore, the glucose: fructose ratio increases in leaves concomitantly with the sucrose and starch increase in the basal part, which coincide with the first tubers apparition. Sucrose degraded by invertases is associated with tuber initiation and sucrose synthase assure their filling
6

Blenau, Wolfgang, Ricarda Scheiner, Stephanie Plückhahn, Bahar Oney, and Joachim Erber. "Behavioural pharmacology of octopamine, tyramine and dopamine in honey bees." Universität Potsdam, 2002. http://opus.kobv.de/ubp/texte_eingeschraenkt_verlag/2010/4430/.

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In the honey bee, responsiveness to sucrose correlates with many behavioural parameters such as age of first foraging, foraging role and learning. Sucrose responsiveness can be measured using the proboscis extension response (PER) by applying sucrose solutions of increasing concentrations to the antenna of a bee. We tested whether the biogenic amines octopamine, tyramine and dopamine, and the dopamine receptor agonist 2-amino-6,7-dihydroxy-1,2,3,4-tetrahydronaphthalene (6,7-ADTN) can modulate sucrose responsiveness. The compounds were either injected into the thorax or fed in sucrose solution to compare different methods of application. Injection and feeding of tyramine or octopamine significantly increased sucrose responsiveness. Dopamine decreased sucrose responsiveness when injected into the thorax. Feeding of dopamine had no effect. Injection of 6,7-ADTN into the thorax and feeding of 6,7-ADTN reduced sucrose responsiveness significantly. These data demonstrate that sucrose responsiveness in honey bees can be modulated by biogenic amines, which has far reaching consequences for other types of behaviour in this insect. (C) 2002 Elsevier Science B.V. All rights reserved.
7

Hatton, Pierre-Joseph. "Séquestration du carbone et de l’azote des feuilles de hêtre dans les associations organo-minérales du sol : Approches macroscopiques, nanométriques & moléculaires." Electronic Thesis or Diss., Paris, AgroParisTech, 2012. http://www.theses.fr/2012AGPT0050.

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Les associations organo-minérales jouent un rôle prépondérant dans la séquestration à long terme des matières organiques des sols forestiers, mais les contributions des différents types d’association organo-minérale à la stabilisation, ainsi que les processus microbiens qui en sont responsables, restent mal connus. Pour y remédier, des techniques de traçage isotopique ont été combinées à la séparation densitométrique séquentielle des associations organo-minérales. Ces dernières ont été investiguées in et ex situ, à différentes échelles spatiales (macroscopique, submicrométrique et moléculaire) et temporelles (de 8 heures à 12 ans).Quatre types d’association organo-minérale ont été distingués : les débris végétaux associés à quelques rares minéraux, les agrégats végétaux, les agrégats microbiens et les grains minéraux. Le traçage isotopique du carbone et de l’azote dérivés des litières de feuilles a mis en évidence, à l’échelle de la décennie, des transferts entre les différentes associations organo-minérales. Tous deux entrent dans le sol sous forme de fragments végétaux, puis migrent progressivement vers les agrégats végétaux et microbiens. Les agrégats apparaissent pertinents pour la stabilisation du carbone et de l’azote à l’échelle décennale. Une petite fraction du carbone et de l’azote apparaît rapidement stabilisée dans les grains minéraux denses. Nos observations du devenir du 15N indiquent que l’activité des microorganismes du sol est responsable de ces transferts. Les fragments de feuilles colonisés par les microorganismes sont progressivement incorporés dans les agrégats végétaux. A mesure que la décomposition se poursuit, les agrégats végétaux se disloquent pour former des agrégats plus stables, plus pauvres en matières organiques, plus enrichis en produits microbiens et plus compacts : les agrégats microbiens. La stabilisation microbienne a été étudiée aux échelles macroscopique, submicrométrique et moléculaire, principalement par NanoSIMS et LC-IRMS. Elle opère (i) directement par immobilisation dans les cellules microbiennes et (ii) indirectement via une abondante production de métabolites extracellulaires. La calibration des C/N obtenus par NanoSIMS a permis de déterminer qu’ils sont stabilisés dans les associations organo-minérales sans contrôle apparent de la chimie des matières organiques. L’incorporation du 13C dans les sucres aminés, biomarqueurs des biomasses bactériennes et fongiques, indique que les microorganismes vivants croissent où la ressource se trouve. Ils s’accumulent dans les agrégats microbiens via les processus de transfert précédemment évoqués. Ce travail souligne l’importance des agrégats pour la séquestration du carbone et de l’azote dérivés des litières à l’échelle de la décennie. Il met également en évidence le rôle des microorganismes dans les transferts et la stabilisation du carbone et de l’azote dérivés des feuilles au sein d’associations organo-minérales
Organo-mineral associations play a key role in the long-term sequestration of organic matter in forest soils. However, knowledge about the contribution of the different types of organo-mineral associations and the microbial processes involved in soil organic matter stabilisation is scant. To solve it, stable isotope techniques have been combined with the sequential density fractionation of organo-mineral associations. Isolated fractions were investigated in field and in lab, at different temporal (from 8 hours to 12 years) and spatial scales (macro-, submicron- and molecular scales).Four types of organo-mineral associations were distinguished: plant debris with little mineral attached, plant aggregates, microbial aggregates and mineral grains. Isotopically labeled beech leaf litters were tracked at a decadal time-scale to reveal transfers in between organo-mineral associations. Both litter-derived carbon and nitrogen entered the soil as plant fragments to progressively pass through plant and microbial aggregates. Aggregates appeared particularly meaningful for the stabilisation of litter-derived carbon and nitrogen at a decadal time-scale. Little of the litter-derived carbon and nitrogen was found quickly stabilized to mineral grains. Microbial activities appeared as a major controlling factor for the evolvement of organo-mineral associations, responsive for the transfers of litter-derived carbon and nitrogen. Indeed, plant debris colonized by microorganisms are progressively trapped into plant aggregates. As decomposition proceeds, plant aggregates disrupt into denser microbial aggregates. These aggregates are loaded with lesser organic matter, but enriched in stable microbial materials.Stabilisation by soil microorganisms has been studied at the macro-, submicronand molecular- scales, using mostly NanoSIMS and LC-IRMS. Microbial stabilization operated (i) directly through immobilization in microbial cells and, (ii) indirectly through large production of extracellular microbial products. By calibrating the NanoSIMS for accurate C/N ratios, extracellular microbial products have been shown to be stabilized onto organo-mineral associations without apparent control of the mineral-attached organic matter chemistry. The incorporation of 13C tracers into amino sugars, biomarkers of bacterial and fungal biomasses, revealed that living microorganisms grow where the resource is, but accumulate in microbial aggregates. Microbial biomasses moved from plant debris to microbial aggregates, likely along with the transfers of decaying litter residues as described above.This work points aggregates as meaningful organo-mineral associations for the sequestration of litter-derived carbon and nitrogen at the decadal time-scale. It also revealed the role of microorganisms in the transfers and stabilization of litterderived carbon and nitrogen within organo-mineral associations
8

Samadi, Mohammad. "Nouvelle voie d'accès aux homologues supérieurs de sucres et de nucléosides par décarboxylation radicalaire." Paris 11, 1989. http://www.theses.fr/1989PA112410.

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Ce travail présente la synthèse de molécules d'intérêt biologique en utilisant la chimie radicalaire et, plus particulièrement, en exploitant la réaction de décarboxylation radicalaire mise au point par Barton et coll. La réaction d'addition de radicaux, issus de la décarboxylation des esters thiohydroxamiques des acides uroniques, sur les oléfines a été appliquée dans le but de synthétiser des homologues supérieurs de sucres et de nucleosides. Deux résultats principaux ont été obtenus: d'une part, la réaction s'est avérée stéréospécifique dans le cas des acides uraniques possédant une fonction cétale adjacente au radical et, d'autre part, la réaction se déroule avec une bonne stéréosélectivité dans le cas des acides dérivés des désoxy-2'-nucleosides possédant un groupe encombrant en C-3'. A partir de ces résultats, nous avons pu réaliser la synthèse totale de la sinéfungine naturelle (S), de son épimère (R) en C-6', ainsi que des analogues dans lesquels la base adénine a été remplacée par l'uracile. Il est intéressant de noter que l'épimère (R) de la sinéfungine conserve une bonne activité antiparasitaire sur la croissance de Leishmania donovani comparée à celle de la sinéfongine naturelle. Enfin, la dernière partie de ce travail est consacrée à la synthèse, par voie radicalaire, de dérivés phosphonates dans le domaine des sucres, des nucléosides et des acides aminés. En particulier, nous décrivons la synthèse totale de l'isostère-phosphonate de l'azido-3'­ désoxy-3'-thymidine-5' monophosphate (AZT-5' monophosphate) dans le but d'améliorer l'indice thérapeutique de l'AZT, seul médicament efficace, à l'heure actuelle, pour lutter contre le virus du Sida
We describe in this thesis our extensive investigations to produce new types of molecules with structural novelty and biological potency in the field of carbohydrates and nucleosides, using free radical chemistry. The first chapter deals with the general procedure of radical decarboxylation reaction of uronic acids via their N-hydroxy-2-pyridon esters. The radical generated can be easily captured by electron deficient alkenes, leading to highly functionalised chain-elongated pentofuranosides, hexopyranosides and nucleosides. These carbon-carbon bond forming reactions can occur stereospecifically in an anti-addition fashion, if the radical is adjacent to cyclic dimethylketal protecting group. In the case of 2'-deoxynucleosides and in the presence of a bulky protecting group at C-3', we also experienced a good stereoselectivity. In the second part, we present the enantioselective total synthesis of natural sinefungin (S) and sinefungin (R), epimers at C-6' and also their hitherto unknown analogues in which the adenine is replaced by uracil. It is interesting to note that the epimer (R) of sinefungin preserves an excellent antiparasitic activity against Leishmania donovani promastigotes in vivo compared with natural sinefungin. Finally in the third part, we report the synthesis of phosphonic analogues of sugars, nucleosides and amino acid derivatives by the use of radical addition to vinylphosphonate as outlined in the first chapter. Particularly interesting is the synthesis of an isostere­phosphonate of 3'-azido-3'-deoxy-thymidine-5'-monophosphate (AZT-5'-monophosphate). Hopefully this molecule might display a better therapeutic index than AZT, the only efficient anti-HIV drug in clinical use
9

Rahmani, Fatima. "Contribution à l'étude des mécanismes de résistance à la salinité de quelques espèces fongiques du genre aspergillus." Nancy 1, 1989. http://www.theses.fr/1989NAN10079.

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Le travail porte sur les mécanismes de résistance à la salinité de trois champignons du genre aspergillus : A. Ruber qui montre une grande tolérance aux sels, A. Cervinus qui est totalement inhibé et A. Niger qui révèle un comportement intermédiaire. Après détermination des conditions optimales de croissance, il a été montré que la réaction de ces champignons à la salinité ne dépend pas des ions composant le sel, mais est créée par le potentiel osmotique. Les plus importants osmolytes organiques et inorganiques analysés sont : polyols (glycérol, érythritol, mannitol, arabitol), acides aminés (glutamate, glutamine, alanine), sucres (glucose, fructose, théhalose), ions (potassium, sodium, chlorures). Le glycérol est de loin l'osmolyte le plus important dans les cellules stressées et est également excrété dans le milieu de culture. Il y a une bonne corrélation entre le degré de résistance des champignons au stress salin et la présence de ces molécules. Des enzymes impliquées dans la synthèse des acides aminés (GOT, GPT, GDH à NADP) et le métabolisme des polyols (mannitol deshydrogènase, dihydroxyacétone réductase) voient leur activité augmenter en fonction de la salinité. Le travail se termine par la mise en évidence par électrophorèse bidimentionnelle de nouvelles protéines qui apparaissent lors du stress salin spécialement chez A. Cervinus
10

Dominguez, Hélène. "Croissance et flux métaboliques de Corynebacterium glutamicum sur divers sucres : interactions entre transporteurs PTS et voies métaboliques : [thèse en partie soutenue sur un ensemble de travaux]." Toulouse, INSA, 1994. http://www.theses.fr/1994ISAT0051.

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Les comportements cinetiques de corynebacterium glutamicum ont ete clairement determines sur glucose, sur fructose, sur saccharose et sur melange de glucose et de fructose. Sur fructose, les contraintes metaboliques, a savoir un flux gluconeogenique fournissant les hexoses phosphates necessaires a la biosynthese cellulaire et un flux limite dans la voie des pentoses, sont correlees a un rendement en biomasse peu eleve mais aussi a un debordement de metabolisme conduisant a la production de dihydroxyacetone et de lactate. Ce phenomene a ete attribue a une regulation negative de la glyceraldehyde-3-phosphate deshydrogenase et de la pyruvate deshydrogenase occasionnee par une augmentation du rapport nadh/nad mais aussi dans le cas du lactate, a une activation de l'activite de la lactate deshydrogenase par un pool eleve en fructose-1,6-diphosphate. Ces phenomenes attestent d'un desequilibre energetique, ou la cellule se trouve en exces d'energie qui est la consequence d'un flux glycolytique important aux depens de la voie des pentoses et un manque de nadph. L'isolement, par mutagenese a l'ethylmethanesulfonate, de mutants deficients pour le pts-mannose et/ou pts-fructose a permis d'une part d'identifier les divers transporteurs impliques dans la permeation du glucose ou du fructose et leur contribution reelle dans le transport de chaque sucre et d'autre part de preciser le role du pts-fructose dans la phosphorylation de la moitie fructose du saccharose. Les phenotypes de ce mutants ont permis d'etablir que le fructose genere a l'interieur de la cellule par l'hydrolyse du saccharose-6-phosphate est excrete avant d'etre transporte et phosphoryle par le pts-fructose. Par ailleurs, des conditions precises de melanges de substrats (glucose/fructose) nous ont conduit a decrire les mecanismes de regulation des systemes pts conduisant au cometabolisme du glucose et du fructose

Книги з теми "Sucres amines":

1

Carnegie, Dale. Cómo ganar amigos e influir sobre las personas. Buenos Aires: Editorial Sudamericana, 2006.

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2

Levine, Stuart R. Descúbrase como líder: Cómo ganar amigos, influir sobre las personas y tener éxito en un mundo cambiante. Buenos Aires: Editorial Sudamericana, 1993.

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3

Huaman, Henry Quintanilla. Los Amigos de Odiseo: Los Locos Del Arco de Sucre. Independently Published, 2018.

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4

Cmo Ganar Amigos E Influir Sobre Las Personas. Vintage Books USA, 2010.

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5

Carnegie, Dale. Cómo ganar amigos e influir sobre las personas. Sudamericana, 1999.

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6

Carnegie, Dale. Como Ganar Amigos E Influir Sobre las Personas / How to Win Friends and Influence People. Debolsillo, 2006.

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7

Carnegie, Dale. Como Ganar Amigos E Influir Sobre Las Personas, Edicion Revisada/How to Win Friends and Influence People. Giron Spanish Book Distributors, 1986.

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8

Enjoy Your Life. Dar-us-Salam Publications, 2008.

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9

Carnegie, Dale. Como Ganar Amigos E Influir Sobre Las Personas, Edicion Revisada/How to Win Friends and Influence People. Grijalbo, 2000.

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10

Carnegie, Dale. Como Ganar Amigos E Influir Sobre Las Personas/ How to Win Friends and Influence People (Autoayuda / Self-Help). Sudamericana, 2006.

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Частини книг з теми "Sucres amines":

1

Tredell, Nicolas. "Snakes and Ladders: Success (1978)." In The Fiction of Martin Amis, 34–43. London: Macmillan Education UK, 2000. http://dx.doi.org/10.1007/978-1-137-19344-5_4.

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2

Smollett, Tobias. "Chapter XLIII." In The Adventures of Roderick Random. Oxford University Press, 2008. http://dx.doi.org/10.1093/owc/9780199552344.003.0043.

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We lodge at a house near Amiens,1 where I am robbed by the capuchin, who escapes while I am asleep——I go to Noyons in search of him, but without success——I make my condition known to several people; but find no relief——...
3

Barlos, Kleomenis, and Dimitrios Gatos. "Convergent peptide synthesis." In Fmoc Solid Phase Peptide Synthesis. Oxford University Press, 1999. http://dx.doi.org/10.1093/oso/9780199637256.003.0013.

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Besides the classical step-by-step synthesis, the convergent solid phase peptide synthesis (CSPPS) was developed for the preparation of complex and difficult peptides and small proteins. According to this method, suitably protected peptide fragments spanning the entire peptide sequence and prepared on the solid phase are condensed, either on a solid support or in solution, to the target peptide. Convergent synthesis is reviewed in recent publications. In this chapter, full experimental details are given for the preparation of complex peptides by applying convergent techniques, using 2-chlorotrityl chloride resin (CLTR) and Fmoc-amino acids. In the step-by-step peptide chain elongation the resin-bound C-terminal amino acid is reacted sequentially with suitably protected and activated amino acids. The peptide is thus elongated steadily towards the N-terminal direction. This is advantageous over the opposite direction where the elongation is performed from the N- to the C-terminus, because in the second case the growing peptide is activated at the C-terminal amino acid, which leads to its extensive racemization. This limits considerably the synthetic possibilities of the method. In convergent synthesis, no directional restrictions exist and the chain elongation can be performed with equal possibility to be successful to any direction. Figure 1 describes schematically the C- to N-terminal synthesis which is the most studied to date. The strategies where the synthesis begins from a central fragment and the peptide chain is extended to both C- and N-terminal directions and from the N-terminal towards the C-terminal can be considered, at the present time, to be in its infancy. In general, protected peptide fragments of any length can be used in the condensation reaction, if they are of satisfactory purity and solubility. Usually, fragments of up to 15 amino acids in length are used, because of their simpler purification by RP-HPLC compared with the longer peptides. The solubility of protected peptide acids is independent of their length. The selection of the correct fragments is very important for the success of convergent synthesis. It is helpful to analyse all available structural information, determined or calculated, for the target peptide. Peptide regions where β-turns are known to occur are readily identified as ‘difficult’ sequences during their synthesis.
4

Morrow, Gary W. "Biosynthesis of Carbohydrates and Amino Acids." In Bioorganic Synthesis. Oxford University Press, 2016. http://dx.doi.org/10.1093/oso/9780199860531.003.0006.

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We have already seen that some of the basic building blocks used in the biosynthesis of natural products are amino acids such as phenylalanine, tyrosine, and others. These and other crucial construction materials such as the acyl group in acetyl-CoA are all ultimately derived from carbohydrates. In this chapter, we will present an abbreviated overview of the components of carbohydrate structure and metabolism sufficient for our purposes going forward, with a schematic flowchart showing how carbohydrates and amino acids are modified, combined, and branched off in various ways to yield the distinct set of biosynthetic pathways that will form the core of the remainder of the text. We will finish the chapter with a brief, general review of amino acid nomenclature and structure with emphasis on the key amino acids that will be used throughout the remainder of the text. We know that plants make glucose (C6H12O6) by photosynthesis using light, water (H2O), and carbon dioxide (CO2). Another way of looking at the formula for glucose is C6(H2O)6, that is, six carbon atoms and six water molecules. Thus, glucose was originally referred to as a hydrated form of carbon—a carbohydrate. But this is a very general term since there are many different types of carbohydrate compounds. One way to broadly classify carbohydrates is to identify them as either mono- (one), di- (two), oligo- (a few) or poly- (many) saccharides. For example, glucose (C6H12O6) cannot be broken down into simpler carbohydrates by simple hydrolysis, so it is classified as a monosaccharide, that is, a single, discrete carbohydrate compound. On the other hand, the carbohydrate sucrose (C12H22O11) is classified as a disaccharide since when it is subjected to aqueous hydrolysis, it yields two different monosaccharide carbohydrates, namely glucose (C6H12O6) and fructose (C6H12O6). Noting that glucose and fructose are different compounds but with the same molecular formula, they must be related to one another either as stereoisomers or as constitutional isomers, so further refinement of classification is needed. Structurally speaking, most monosaccharide carbohydrates are simply polyhydroxyaldehydes (aldoses) or polyhydroxyketones (ketoses) which can be further classified using a combination of aldo- or keto- prefixes along with suffixes such as triose, tetrose, pentose, or hexose to designate the number of carbon atoms.
5

"Atroposelective Reactions." In Chirality from Dynamic Kinetic Resolution, 243–81. The Royal Society of Chemistry, 2011. http://dx.doi.org/10.1039/bk9781849731973-00243.

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Atropisomerism has opened new ways for DKR processes by exploiting the interconversion of atropisomeric unstable compounds as a beneficial property. The cleavage of a short bridge that causes configurational instability allows an elegant access to axially chiral biaryl products. Thus, Bringmann has demonstrated that biaryl lactones could be ring opened with chiral nucleophiles according to the principle of DKR. This cleavage can be achieved highly atropo-enantio- or -diastereoselectively by involving a range of chiral metallated nucleophiles including metallated amines, alcohols, C-nucleophiles or hydride transfer reagents; by using uncharged chiral or achiral nucleophiles after Lewis acid activation of the lactone; or by involving a η6-coordination of a transition metal fragment to one of the aromatic rings of the biaryl lactone. Moreover, the last fifteen years have seen novel families of atropisomers based on structures other than biaryls come forward as potential new starting materials for DKRs. Among them, atropisomeric anilides, benzamides and naphthamides have been resolved through DKR. Despite the prevalence and importance of atropisomerism in organic structures, the field of asymmetric catalysis has not yet recorded extensive success in the development of catalysis. Among the best recent results of atropo-enantioselective reactions are aldol reactions of atropisomeric benzamides and naphthamides using L-proline as organocatalyst developed by Walsh; nickel-catalysed cross coupling of dibenzothiophenes with Grignard reagents performed in the presence of chiral phosphines developed by Hayashi; ring-opening of biaryl lactones with methanol catalysed by AgBF4 combined with (R)-BINAP developed by Yamada; and DKR of biaryl atropisomers via peptide-catalysed bromination developed by Miller.
6

Alhaji Saganuwan, Saganuwan. "Toxicosis of Snake, Scorpion, Honeybee, Spider, and Wasp Venoms: Part 2." In Medical Toxicology. IntechOpen, 2021. http://dx.doi.org/10.5772/intechopen.93935.

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Toxicosis is a poisoning caused by venomous animals such as snake, scorpion, honeybee, spider and wasp. Their poisons contain amino acids, peptides, proteins, enzymes and metallic ions that are responsible for neurotoxicity, hemotoxicity and myotoxicity. Because of in vivo therapeutic challenges posed by toxicosis, there is need for ideal therapeutic agents against envenomation caused by venomous animals. Findings have shown that toxicosis could be treated symptomatically. Snake and scorpion antivenins could be used for treatment of poisoning caused by snake, scorpion, honeybee, spider and wasp. The amount of antivenin is dependent on the quantity of venom injected into the affected individuals. Moreso, sympotomatic treatments are also done according to the systems affected. Hospitalization is necessary for assessment of therapeutic success.
7

Alhaji Saganuwan, Saganuwan. "Toxicosis of Snake, Scorpion, Honeybee, Spider, and Wasp Venoms: Part 1." In Medical Toxicology. IntechOpen, 2021. http://dx.doi.org/10.5772/intechopen.92804.

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Toxicosis is a poisoning caused by venomous animals such as snake, scorpion, honeybee, spider, and wasp. Their poisons contain amino acids, peptides, proteins, enzymes, and metallic ions that are responsible for neurotoxicity, hemotoxicity, and myotoxicity. Because of in vivo therapeutic challenges posed by toxicosis, there is need for ideal therapeutic agents against envenomation caused by venomous animals. Findings have shown that toxicosis could be treated symptomatically. Snake and scorpion antivenins could be used for treatment of poisoning caused by snake, scorpion, honeybee, spider, and wasp. The amount of antivenin is dependent on the quantity of venom injected into the affected individuals. More so, symptomatic treatments are also done according to the systems affected. Hospitalization is necessary for assessment of therapeutic success.
8

Agus, Ali, and Agussalim Agussalim. "Approach for the Domestication and Propagation of Stingless Bees." In Advances in Environmental Engineering and Green Technologies, 69–80. IGI Global, 2023. http://dx.doi.org/10.4018/978-1-6684-6265-2.ch004.

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Domestication and propagation in stingless bees is called meliponiculture. The aims of meliponiculture are to make it easier to control the colonies health and development and to make it easy when harvesting stingless bee products (honey, bee bread, and propolis), furthermore, for advanced study and development like multiple colonies, to produce honey, bee bread, and propolis. Therefore, this paper focuswa on stingless bees Tetragonula laeviceps: the domestication and propagation technique, production of stingless bee products (honey, bee bread, and propolis), the daily activity of workers (foragers), the chemical composition (glucose, fructose, sucrose, reducing sugar, moisture, protein, ash, phenolic, flavonoid, vitamin C, antioxidant activity, minerals content, and amino acids) of honey from T. laeviceps, the pests and the challenges in meliponiculture of stingless bees.
9

Galembeck, Fernando, Gabriela Alves Macedo, and Yara Csordas. "Chemicals from Sugarcane." In Materials for a Sustainable Future, 246–78. The Royal Society of Chemistry, 2012. http://dx.doi.org/10.1039/bk9781849734073-00246.

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Sugarcane has been a source of many chemicals in Brazil since the early 1940s. The increase in sugarcane production associated with the growing global demand for food (sucrose) and fuel (ethanol) has, since the early 1970s, led to a steady decrease in production costs and transformed sugarcane into an environmentally benign and economically competitive alternative to oil. Sugarcane is already a competitive feedstock for the production of a host of chemicals, including thermoplastics, solvents, surfactants, esters, ethers, carboxylic acids, amino acids, polyelectrolytes, gums and cellulose. Recent work, especially in Brazil, has produced a large number of new possibilities and many companies are implementing these. This chapter describes many examples of current products derived from sugarcane and also discusses possible future developments in this area.
10

Bogahawaththa, Dimuthu, and Todor Vasiljevic. "Advances in dairy protein science: whey proteins." In Understanding and improving the functional and nutritional properties of milk, 183–240. Burleigh Dodds Science Publishing, 2022. http://dx.doi.org/10.19103/as.2022.0099.06.

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Whey proteins are highly nutritious and commercially important proteins from the serum phase of milk. Amino acid profile, digestion and absorption behavior in the gut in addition to various physical functionalities make them a highly sought after protein group in broad range of commercial applications. However, their application is hindered by their inherent instability upon exposure to extrinsic stressors, mainly heat. Their stability can be improved by applying various approaches including physical, chemical and enzymatic with various success. The following pages will cover briefly properties of main whey proteins and their denaturation and aggregation kinetics, impact of shear on whey protein behavior during denaturation and aggregation and impact on their functionality. The special emphasis is given to creation of Pickering type of stabilisers and their application in stabilisation of emulsions and foam.

Тези доповідей конференцій з теми "Sucres amines":

1

May, Preston, Jay P. Deville, and Jeffrey Miller. "Shale Inhibitor Tracking for High-Performance Water-Based Drilling Fluids." In IADC/SPE International Drilling Conference and Exhibition. SPE, 2022. http://dx.doi.org/10.2118/208721-ms.

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Abstract Drilling wells with water-based fluid systems can be problematic due to the water reactivity of clay-containing shale minerals. This fundamental issue is the most often cited performance gap between non-aqueous fluid (NAF) and water-based fluids (WBF). The consequences of uncontrolled shale hydration include issues such as bit-balling/accretion, reduced ROP, wellbore collapse, and overall increased wellbore construction costs. This problem is typically addressed by the addition of shale inhibitors which can span multiple types of chemistries. The maintenance of these additives is nuanced due to their inherent depletion on reactive minerals leading to uncertainty of active concentration of these additives during a drilling campaign. Considering the critical need to maintain concentrations of these additives, uncertainty is not an optimal plan to ensure success. To this end, we have designed quantitative shale inhibitor tracking technology to measure amine-based shale inhibitors in high-performance water-based fluids. The method is robust, detects only amine-based swelling inhibitors, and is fully amenable to be performed at a rig site. We developed a colorimetric assay that quantitatively measures amine-based shale inhibitors in filtrates of WBFs. The reaction to generate color utilizes proprietary reagents that selectively target only the amines of interest, and is not influenced by nitrogen-containing polymers such as polyacrylamides. Additionally, the results of the test are not influenced by any common drilling fluid additives, including black powders. The colored solutions produced in the test are measured by advanced spectroscopic analysis with a handheld, portable field meter at a specific wavelength. The absorbance is used to determine the concentration of the amine inhibitor in the fluid filtrate. Finally, we have tested reliability of the method through numerous approaches including Gage Repeatability and Reproducibility statistical analysis. With this new technology, we have explored amine depletion on reactive clays in a lab setting, uncovering unique depletion rates based on amine chemistry. Additionally, we have trialed this technology in multiple wells. We have validated the test method and equipment to be field friendly and accurate, as designed. Our field engineers have included this new measurement alongside a typical mud check. In our validation trials we have already observed different depletion rates based on well and operational procedures for amine inhibitor maintenance, and conflicting values of measured concentrations and product concentration estimates based on calculations. We have coupled high-performance fluid design with shale inhibitor tracking technology to reduce the uncertainty of WBF chemical composition. This technology will allow us to sustain effective concentrations of high-performance additives and improve operational reliability throughout the wellbore construction process. Furthermore, this technology will allow more effective re-use of WBF, reducing the environmental impact of our fluids, and lowering well costs.
2

Adiwibowo, D. "The Success Story of H2S Scavenger Injection as Temporary Solution to Maintain Production During One of Two Amine Regeneration System Breakdown in X Gas Plant." In Indonesian Petroleum Association - 46th Annual Convention & Exhibition 2022. Indonesian Petroleum Association, 2022. http://dx.doi.org/10.29118/ipa22-f-81.

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X gas plant has 4 process trains and one bypass train with capacity 800 MMscfd. Each process Train equipped with Amine contactor to reduce the CO2/H2S to below gas specification 5% mole CO2 and 8 ppm H2S. Rich Amine from contactors then regenerated through two Amine regenerator, heating media used hot water which maintained its temperature by using fired heater. X gas plant had experience breakdown of one Amine regenerator, which decreases plant capacity to 640 MMscfd. Impact of one regenerator breakdown the lean amine circulation rate decreases from total 1540 USGPM to 910 USGPM, with limited amine circulation to maintain liquid turndown at Amine contactor packing, Train-1/2/3 circulated with Amine, while Train-4 with no amine circulation. Several options were evaluated, application of H2S Scavenger Injection come up as the most probable option considering cost and time. Hydroxyethyl-triazine based was selected. Uncontrolled reaction and improper injection technique will lead to inefficient treating dosages and unwanted by-products. By combining knowledge of scavenger stoichiometric reaction with H2S, triazine content, spray nozzle injection technique, and produced water scale tendency, succeed to reduce the H2S content and reverting plant capacity to 800 MMscfd.). H2S Scavenger is injected through spray-nozzle installed in 12” gas line header upstream of Cooler Train #4 at 140OF and ±1250 psig. Initial injection is started with ±105 MMscfd treated gas which provide 24 second contact time with 0.45 L scavenger/MMscfd. As the initial treatment succeed to reduce H2S content from 35 to below 5 ppm, treated gas flowrate then increased gradually to 150 MMscfd and further to 220 MMscfd with 0.5 and 0.55 L/MMscfd scavenger dosage respectively. Increased treating dosage sufficiently maintain H2S scavenging efficiency with 50% reduced of contact time. H2S Scavenger direct injection could be considered as temporary solution program during such disturbance of amine system performance. The Amine regenerator repair was consumed 118 days, while H2S scavenger application was implemented after 34 days Amine regenerator repair activity until amine heater completed repair and back online which is for 84 days injection. In this case H2S Scavenger injection can optimize X gas plant sales gas 9.05 BSCF (equivalent with 55 MMUSD) with additional operating cost 0.916 MMUSD.
3

Zibaii, M. I., H. Latifi, M. Karami, M. Gholami, S. M. Hosseini, and M. H. Ghezelayagh. "Biconical tapered optical fiber biosensor for measuring refractive index of a-amino acids in aqueous D-glucose and sucrose solution." In SPIE Photonics Europe, edited by Jürgen Popp, Wolfgang Drexler, Valery V. Tuchin, and Dennis L. Matthews. SPIE, 2010. http://dx.doi.org/10.1117/12.853969.

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4

Liu, Huazhen, Micah Pope, Todd Doehring, Pradeep Kachroo, and David Hildebrand. "Review of the Quality of Soybeans Grown in Different Geographic Areas." In 2022 AOCS Annual Meeting & Expo. American Oil Chemists' Society (AOCS), 2022. http://dx.doi.org/10.21748/tboo7714.

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Previous reports indicate variable soybean quality parameters exported/shipped from different geographic regions. This review summarizes the quality of soybeans grown under diverse environmental conditions from the three main exporting countries. Soybeans from the US and Brazil have similar levels of protein and oil but US soybeans have higher foreign material and lower heat damage or total damage than soybeans from Brazil. US and Brazil meal is reported to have higher crude protein than meal from Argentina. At equal crude protein content, USA meals had less fiber, more sucrose and lysine and better protein quality than South American meals. Methionine, threonine and cysteine levels were similar in soybean protein from US and Argentina and higher than levels of these three amino acids in soybean protein from Brazil. Soybean oil from Brazil had higher free fatty acids, neutral oil loss, phosphorus, calcium and magnesium than oil from the US or Argentina. Environmental conditions under which soybeans are grown can have a large impact on chemical composition and nutrient quality of soybean oil.
5

Briner, Andreas, Alexey Moiseenkov, Romain Prioul, Safdar Abbas, Sergey Nadezhdin, and Nihat Gurmen. "Hydraulic Fracture Initiation and Propagation Model Provides Theoretical Ground for Hybrid-Type Fracturing Schedules in Unconventional Gas Reservoir in the Sultanate of Oman." In SPE Middle East Unconventional Resources Conference and Exhibition. SPE, 2015. http://dx.doi.org/10.2118/spe-172950-ms.

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Abstract A recent series of tight gas discoveries in the Amin formation of the greater Fahud area represents some of the most exciting exploration success of this decade in the Sultanate of Oman. The structures have been evaluated as containing very significant amounts of gas locked in a challenging deep and hot environment requiring hydraulic fracture stimulation. Since their discoveries, the two primary challenges have been difficult breakdown of the formation and limited proppant placement during stimulation attempts. The early experience in the exploration and appraisal campaigns from 2009 to 2014 has led to fracture designs with conservative proppant amounts that could limit the full potential of the field. Several geomechanical studies have been commissioned in the past to guide completion strategies in well placement, perforation, and fracture stimulation design. The objectives of this study were to model hydraulic fracture initiation and breakdown in the three Amin zones (upper, middle, and lower) to provide some theoretical understanding of the impact of the different parameters on the observed field breakdown pressures. In agreement with field observations, the model showed that lowering the viscosity of the pad has a major impact in lowering the breakdown pressures. Consequently, current best practices include formation breakdown and hydraulic fracture propagation with low-viscosity fluids followed by proppant placement with high-viscosity fluids. When applied to tight gas formations in the Sultanate of Oman, the hybrid fracturing evolves from conventional designs for the purpose of successful fracture initiation, while still placing a successful job.
6

Bu Ali, Ahmed Khalid, Mohammed Khalid Almusaiteer, and Abdulaziz Saleh Sharaf. "Innovative Approach to Maximize NGL Recovery Utilizing Process Modeling in Midstream Operations." In ADIPEC. SPE, 2022. http://dx.doi.org/10.2118/211281-ms.

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Abstract The aim of this paper is to showcase successful operations of maximizing C2+ Natural Gas Liquids (NGL) recovery in a midstream NGL Recovery Plant utilizing process modeling and simulation. Gas Treating Trains in Plant-A are designed to remove the CO2 from the sour feed gas using Di-Glycol Amine (DGA) and route the sweet gas to the NGL Recovery trains. To maximize the NGL recovery in Plant A, process modeling and simulation, using ProMax software, was utilized to identify any limitations in the Gas Treating trains and examine the possibility of processing higher feed gas than the design capacity. Main hydraulic parameters in the DGA absorber and regenerator were confirmed to be within the acceptable limit to handle additional amount of gas calculated from the simulation. A detailed procedure was prepared to process higher feed gas in the Gas Treating trains. Processing higher feed gas at the Gas Treating trains has resulted in increasing the sweet gas production by 7% which was processed smoothly at the Gas Treating trains without abnormalities. Process parameters were closely monitored to ensure a safe and reliable operation. On-spec sweet gas was delivered which was verified by collecting gas samples and by monitoring the sweet gas CO2 online analyzer. In addition, no foaming symptoms were observed during processing the additional gas. The lean DGA and rich DGA velocities were below the maximum. The by-products of the DGA-sour gas reaction were maintained within the acceptable range which indicates that the reclaimer is functioning properly. Moreover, the lean DGA loading was acceptable and within the specification which is an indication of the DGA regenerator efficient operation. After completing all the required procedures and tests, it was concluded that the Gas Treating trains are able to process additional gas without adding any new equipment or modifying existing ones. The success of maximizing the NGL recovery in Plant-A opens a new frontier for the oil and gas industry to boost the hydrocarbon production and create growth with the value-added of C2+ NGL capitalizing on the hydrocarbon value chain. An innovative approach that combines process simulation with actual implementation in the plant led to higher revenues with no capital expenditure.
7

Rashdi, Khalil Al, and David Spain. "Barik Reservoir Description- An Evolving Concept." In SPE Middle East Unconventional Resources Conference and Exhibition. SPE, 2015. http://dx.doi.org/10.2118/spe-172912-ms.

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Abstract Khazzan field, situated in Block 61 in northern Oman, contains hydrocarbons at several deep levels, including the Barik, Miqrat, Amin and Buah formations. The Barik and Amin reservoirs are being developed in the southern portion of the block to produce 1 bcf/d of gas by end 2017. The development, jointly owned by Oman Oil Company (40%) and BP (60% and operator), will cost over 16 billion US$ and will include a central processing facility and surface facilities for about 300 wells. Most of the wells will be 1000m long horizontal wells, completed using multiple hydraulic fracturing techniques. The two other reservoirs, Miqrat and Buah, contain high H2S levels; these will not be developed at this phase due to high subsurface uncertainties and the cost to process the sour development. This paper presents a case study of an evolving reservoir description of a large, tight gas reservoir, the Barik Formation. It is rare to embark on a major “greenfield” reservoir development of a tight gas reservoir with limited static and almost no dynamic data. The reservoir description is essential to the successful evaluation and management of the inherent subsurface uncertainty at this stage in the field development. Building an associated appraisal plan and being flexible to new understanding is required to make the development a success. The reservoir description is guiding the ongoing appraisal activities in an attempt to reduce the risk and increase the overall project value. This paper presents the evolution of the reservoir description over the last 6 years of BP activity in Block 61 in the Sultanate of Oman. It reviews three stages of reservoir description: Pre-Appraisal, Mid-Appraisal, and Development. The pre-appraisal description was built using the pre-bid data package and published literature to support the commercial access decisions. The Mid Appraisal description provided a health-check for development readiness and appraisal plan revision. Finally, the Development description is presented in a 3D geo-cellular model which is based on the summary of the appraisal activities and supporting field development learnings. The paper discusses these descriptions and the benefits of the changing description, explanation of the advantages of front end loading at the early appraisal stage and how this has led us to our current state
8

Yutkin, M. P., K. M. Kaprielova, S. Kamireddy, A. Gmira, S. C. Ayirala, C. J. Radke, and T. W. Patzek. "Fast Screening of LSW Brines Using QCM-D and Crude Oil-Brine Interface Analogs." In SPE Improved Oil Recovery Conference. SPE, 2022. http://dx.doi.org/10.2118/209389-ms.

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Abstract This work focuses on a potentially economic incremental oil-recovery process, where a brine amended with inexpensive salts (in contrast to expensive surfactants and other chemicals) is injected into a reservoir to increase oil production. Historically, this process received the name of low salinity waterflooding (LSW) although the salinity is not always low(er). Nevertheless, we keep using this terminology for historical reasons. The idea of LSW has been known for three decades, but to the best of our knowledge no specific brine recipes that guarantee success have been presented so far. The reasons hide in the problem's complexity, disagreements in the scientific community, and a race to publish rather than to understand the fundamental principles behind the process. In this paper, we present an experimental model system that captures many of the important fundamental features of the natural process of crude oil attachment to mineral surfaces, but at the same time decomposes this complex process into simpler parts that can be more precisely controlled and understood. We systematically investigate the first-order chemical interactions contributing to the well-known strong attachment of crude oil to minerals using SiO2 as a mineral for its surface chemistry simplicity. Our preliminary results suggest that magnesium and sulfate ions are potent in detaching amino/ammonium-based linkages of crude oil with a SiO2 surface. However, when used together in the form of MgSO4, they lose part of their activity to the formation of a MgSO4 ion pairs. We also find that sulfate-detachment propensity stems not from the interaction with prototype mineral surface, but rather from the interactions with the crude oil-brine interface analog. We continue the systematic study of the ion effects on crude oil detachment, with and more results following in the future.
9

Al Masroori, Haitham H., Abdullah S. Al-Shuely, Nabil S. Al-Siyabi, Salim K. Al-Subhi, Dawood N. Al Kharusi, Roeland Angilst, Patrick Ezechie, and Nadhal Al Marhoon. "Successful Improvement of Ultimate Recovery of Complex Deep Tight Gas Field via Combined Gas Lift De-Liquification Techniques." In Abu Dhabi International Petroleum Exhibition & Conference. SPE, 2021. http://dx.doi.org/10.2118/207395-ms.

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Abstract The Amin top structure is Well defined in seismic data and can be easily interpreted across the entire area of North Oman. It is being identified as an extremely tight, disconnected, low porosity, low permeability, and HPHT reservoir, and thus presents unique challenges to harness its full production potential. Approximately, 15 years after production began with significant pressure depletion below dew point, a significant loss in Well productivity occurred in some of the Wells. Furthermore, during shutdowns or sudden trips of production stations, more Wells faced difficulties to restart again due to mainly, condensate banking and other probable reasons like formation water cross-flow during shut-in, which created a water bank and impaired inflow performance liquid loading due to low Well bore pressure which caused higher static head at the Well tubing. Common practice of N2 lifting CTU becoming no economical with increase number of Wells suffer from Liquid loading and represented a major challenge to look for cheaper economic alternatives. To reduce the higher OPEX associated with nitrogen lifting of Wells, multiple options were considered and evaluated thoroughly including extensive study of several artificial lift methods which were thought to defer liquid loading and mitigate kick-off issues such as Foam lift, Plunger lift, Beam Pump, ESP, Jet Pump and Gas lift (Concentric gas lift). The optimum gas Well de-liquification method has been identified based on the highest UR considering connected GIIP and inflow resistance A (Forchheimer equation Laminar flow). The outcome of the study indicated that a gas lift technology combined with well retubing was recommended as the optimum solution. The injected gas has reduced the density of the liquid resulting in reducing the static head at the tubing which increased the Well bore pressure allowing the Well to flow. A successful robust pilot which has been completed in two Wells and gave conclusive results. The surface development concept encompasses the development, with long term testing. The outstanding successful outcomes of the pilot succeeding in restoring Wells back with economic prolific production rates have led to expedite a full field implementation plan in three fields covering (33 Wells) in the next 5 years. These Wells have similar sub-surface and surface conditions. This paper will highlight the full story of the Gas lift technology implementation and describe in details the entire process starting from the Well candidate selection screening criteria, concept detailed design, critical success factors, project assurances and controls, Injection rate and operating parameters, facility capex, life time cycle and the result tested gas & condensate and water production. Also, the learning and challenges like halite accumulation effects will be shared along with the proven practical mitigation plan that ensured and sustained Well production resulting to significant project success of the technology.
10

Shuely, Abdullah Salim, Hilal Sheibani, Hawraa Al Lawati, Patrick Ezechie, Roeland van Gilst, Nabil Siyabi, Dawood Al Kharusi, Nadhal Marhoon, Louisa Al Otani, and Taha Lawati. "Successful Development of Residual Gas Condensate Reservoir using First ESP in Deep High Pressure and Temperature in Rich Gas Condensate Wells." In Abu Dhabi International Petroleum Exhibition & Conference. SPE, 2021. http://dx.doi.org/10.2118/207502-ms.

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Abstract A rich condensate gas field is located in the North of Oman, which penetrated the Amin sandstone reservoir at 4015 TVDmss. A study was conducted in the field and showed there is ¾ of GIIP trapped with paleo imbibition - over geological time - gas by the water encroachment in an approximately 80 m thick Paleo-Residual Gas zone (PRG), with very low mobility of hydrocarbons and high residual gas saturations. In order to mitigate the shortcomings of such unfavorable subsurface conditions, the study proposed Gas-Aquifer-Rate Management (i.e. co-production of gas and water) utilizing existing flank wells, as a potential field improvement option. The key business drivers for this project are to re-mobilize gas from PRG flank wells and to safeguard existing NFA by Aquifer pump off and production from high rate crestal wells. The optimum gas well deliquification method has been identified based on the highest UR considering connected GIIP and well completion size. The outcome of the study indicated that the ESP technology combined with well retubing was recommended as the optimum solution. Two wells have been selected as ESP candidates to test the new technology to produce water at deep depth (4000m) and high temperature (155°C). A special slim ESP was designed for this purpose. A successful pilot was completed in one well and gave conclusive results. The test showed that the well produced 3K m3/d of gas and 83 m3/d of liquid with 95% BSW. The second pilot is currently in the commissioning phase. The successful outcomes of the pilot succeeding in connecting the gas and restoring wells back with economic production rates will lead to expedite a full field implementation plan. This project will add a significant economic value of positive NPV at low UTC. This paper will highlight the full story of the PRG and ESP technology implementation and describe in details the entire process starting from the artificial lift selection, well candidate selection screening criteria, critical success factors, operating parameters, life-time cycle and the test results of gas and condensate and water production. Also, the learning and challenges in operating the ESP will be shared.

Звіти організацій з теми "Sucres amines":

1

Fisher, Kevin S., Katherine Searcy, Gary T. Rochelle, Sepideh Ziaii, and Craig Schubert. Advanced Amine Solvent Formulations and Process Integration for Near-Term CO2 Capture Success. Office of Scientific and Technical Information (OSTI), June 2007. http://dx.doi.org/10.2172/945367.

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2

Sengupta-Gopalan, Champa, Shmuel Galili, and Rachel Amir. Improving Methionine Content in Transgenic Forage Legumes. United States Department of Agriculture, February 2001. http://dx.doi.org/10.32747/2001.7580671.bard.

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Leguminous forage crops are high in proteins but deficient in S- amino acids. It has been shown that both wool quality and milk production can be limited by the post-ruminal supply of sulfur-containing amino acids. Efforts to use conventional plant breeding and cell selection techniques to increase the S-amino acid content of alfalfa have met with little success. With the objective to increase the S-amino acid content of forage legumes, the goal of this project was to co- express the methionine rich zein genes from corn along with a gene for a key enzyme in methionine biosynthesis, aspartate kinase(AK). The zeins are seed storage proteins from corn and are groupec into four distinct classes based on their amino acid sequence homologies. The b-zein (15kd) and the 6zein (10kD and 18kD) have proportionately high levels of methionine (10%, 22% and 28%, respectively). Initial studies from our lab had shown that while the 15kD zein accumulated to high levels in vegetative tissues of transgenic tobacco the l0kD zein did not. However, co-expression of the 10kD zein with the 15kD zein genes in tobacco showed stabilization of the 10kD zein and the co-localization of the 10kD and 15kD zein proteins in unique ER derived protein bodies. AK is the key enzyme for producing carbon skeletons for all amino acids of the aspartate family including methionine. It is, however, regulated by end-product feedback inhibition. The specific objectives of this proposal were: i. to co-express the 15kD zein with the 10/18kD zein genes in alfalfa in order to enhance the level of accumulation of the 10/18kD zein; ii. to increase methionine pools by expressing a feedback insensitive AK gene in transformants co-expressing the 15kD and 10/18kD zein genes. The Israeli partners were successful in expressing the AK gene in alfalfa which resulted in an increase in free and bound threonine but not in methionine (Galili et al., 2000). Since our target was to increase methionine pools, we changed our second objective to replace the AK gene with the gene for cystathionine gamma synthase (CGS) in the co-expression studies. The first methionine specific reaction is catalyzed by CGS. An additional objective was to develop a transformation system for Berseem clover, and to introduce the appropriate gene constructs into it with the goal of improving their methionine content. Genes for the 15kD zein along with the genes for either the 10kD or 18kD zein have been introduced into the same alfalfa plant both by sexual crosses and by re-transformation. Analysis of these zein co-expressors have shown that both the IOkD and 18kD zein levels go up 5 to 10 fold when co-expressed with the 15kD zein (Bagga et al., MS in preparation). Incubation of the leaves of transgenic alfalfa co-expressing the 15kD and 10kD zein genes, in the rumen of cows have shown that the zein proteins are stable in the rumen. To increase the level of zein accumulation in transgenic alfalfa different promoters have been used to drive the zein genes in alfalfa and we have concluded that the CaMV 35S promoter is superior to the other strong leaf -specific promoters. By feeding callus tissue of alfalfa plants co-expressing the 15kD and 10kD zein genes with methionine and its precursors, we have shown that the zein levels could be significantly enhanced by increasing the methionine pools. We have now introduced the CGS gene (from Arabidopsis; kindly provided to us by Dr. Leustek), into the 15kD zein transformants and experiments are in progress to check if the expression of the CGS gene indeed increases the level of zein accumulation in alfalfa. We were not successful in developing a transformation protocol for Berseem clover.
3

Uni, Zehava, and Peter Ferket. Enhancement of development of broilers and poults by in ovo feeding. United States Department of Agriculture, May 2006. http://dx.doi.org/10.32747/2006.7695878.bard.

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The specific objectives of this research were the study of the physical and nutritional properties of the In Ovo Feeding (IOF) solution (i.e. theosmostic properties and the carbohydrate: protein ratio composition). Then, using the optimal solution for determining its effect on hatchability, early nutritional status and intestinal development of broilers and turkey during the last quarter of incubation through to 7 days post-hatch (i.e. pre-post hatch period) by using molecular, biochemical and histological tools. The objective for the last research phase was the determination of the effect of in ovo feeding on growth performance and economically valuable production traits of broiler and turkey flocks reared under practical commercial conditions. The few days before- and- after hatch is a critical period for the development and survival of commercial broilers and turkeys. During this period chicks make the metabolic and physiological transition from egg nutriture (i.e. yolk) to exogenous feed. Late-term embryos and hatchlings may suffer a low glycogen status, especially when oxygen availability to the embryo is limited by low egg conductance or poor incubator ventilation. Much of the glycogen reserve in the late-term chicken embryo is utilized for hatching. Subsequently, the chick must rebuild that glycogen reserve by gluconeogenesis from body protein (mostly from the breast muscle) to support post-hatch thermoregulation and survival until the chicks are able to consume and utilize dietary nutrients. Immediately post-hatch, the chick draws from its limited body reserves and undergoes rapid physical and functional development of the gastrointestinal tract (GIT) in order to digest feed and assimilate nutrients. Because the intestine is the nutrient primary supply organ, the sooner it achieves this functional capacity, the sooner the young bird can utilize dietary nutrients and efficiently grow at its genetic potential and resist infectious and metabolic disease. Feeding the embryo when they consume the amniotic fluid (IOF idea and method) showed accelerated enteric development and elevated capacity to digest nutrients. By injecting a feeding solution into the embryonic amnion, the embryo naturally consume supplemental nutrients orally before hatching. This stimulates intestinal development to start earlier as was exhibited by elevated gene expression of several functional genes (brush border enzymes an transporters , elvated surface area, elevated mucin production . Moreover, supplying supplemental nutrients at a critical developmental stage by this in ovo feeding technology improves the hatchling’s nutritional status. In comparison to controls, administration of 1 ml of in ovo feeding solution, containing dextrin, maltose, sucrose and amino acids, into the amnion of the broiler embryo increased dramatically total liver glycogen in broilers and in turkeys in the pre-hatch period. In addition, an elevated relative breast muscle size (% of broiler BW) was observed in IOF chicks to be 6.5% greater at hatch and 7 days post-hatch in comparison to controls. Experiment have shown that IOF broilers and turkeys increased hatchling weights by 3% to 7% (P<0.05) over non injected controls. These responses depend upon the strain, the breeder hen age and in ovo feed composition. The weight advantage observed during the first week after hatch was found to be sustained at least through 35 days of age. Currently, research is done in order to adopt the knowledge for commercial practice.

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