Bibliographies thématiques / Microbial metabolism

Sommaire

  1. Articles de revues
  2. Thèses
  3. Livres
  4. Chapitres de livres
  5. Actes de conférences
  6. Rapports d'organisations

Littérature scientifique sur le sujet « Microbial metabolism »

Auteur : Grafiati
Publié le 4 juin 2021
Mis à jour le 9 juin 2025

Créez une référence correcte selon les styles APA, MLA, Chicago, Harvard et plusieurs autres

Choisissez une source :

Consultez les listes thématiques d’articles de revues, de livres, de thèses, de rapports de conférences et d’autres sources académiques sur le sujet « Microbial metabolism ».

À côté de chaque source dans la liste de références il y a un bouton « Ajouter à la bibliographie ». Cliquez sur ce bouton, et nous générerons automatiquement la référence bibliographique pour la source choisie selon votre style de citation préféré : APA, MLA, Harvard, Vancouver, Chicago, etc.

Vous pouvez aussi télécharger le texte intégral de la publication scolaire au format pdf et consulter son résumé en ligne lorsque ces informations sont inclues dans les métadonnées.

Articles de revues sur le sujet "Microbial metabolism"

1

VINOPAL, R. T. "Microbial Metabolism." Science 239, no. 4839 (January 29, 1988): 513.2–514. http://dx.doi.org/10.1126/science.239.4839.513.

Texte intégral
Styles APA, Harvard, Vancouver, ISO, etc.
2

Downs, Diana M. "Understanding Microbial Metabolism." Annual Review of Microbiology 60, no. 1 (October 2006): 533–59. http://dx.doi.org/10.1146/annurev.micro.60.080805.142308.

Texte intégral
Styles APA, Harvard, Vancouver, ISO, etc.
3

ARNAUD, CELIA. "VIEWING MICROBIAL METABOLISM." Chemical & Engineering News 85, no. 38 (September 17, 2007): 11. http://dx.doi.org/10.1021/cen-v085n038.p011.

Texte intégral
Styles APA, Harvard, Vancouver, ISO, etc.
4

Wackett, Lawrence P. "Microbial metabolism prediction." Environmental Microbiology Reports 2, no. 1 (February 8, 2010): 217–18. http://dx.doi.org/10.1111/j.1758-2229.2010.00144.x.

Texte intégral
Styles APA, Harvard, Vancouver, ISO, etc.
5

Hahn-Hägerdal, Bärbel, and Neville Pamment. "Microbial Pentose Metabolism." Applied Biochemistry and Biotechnology 116, no. 1-3 (2004): 1207–10. http://dx.doi.org/10.1385/abab:116:1-3:1207.

Texte intégral
Styles APA, Harvard, Vancouver, ISO, etc.
6

Wackett, Lawrence P. "Microbial community metabolism." Environmental Microbiology Reports 5, no. 2 (March 5, 2013): 333–34. http://dx.doi.org/10.1111/1758-2229.12041.

Texte intégral
Styles APA, Harvard, Vancouver, ISO, etc.
7

Wackett, Lawrence P. "Microbial community metabolism." Environmental Microbiology Reports 15, no. 3 (May 5, 2023): 240–41. http://dx.doi.org/10.1111/1758-2229.13161.

Texte intégral
Styles APA, Harvard, Vancouver, ISO, etc.
8

Rajini, K. S., P. Aparna, Ch Sasikala, and Ch V. Ramana. "Microbial metabolism of pyrazines." Critical Reviews in Microbiology 37, no. 2 (April 11, 2011): 99–112. http://dx.doi.org/10.3109/1040841x.2010.512267.

Texte intégral
Styles APA, Harvard, Vancouver, ISO, etc.
9

Chubukov, Victor, Luca Gerosa, Karl Kochanowski, and Uwe Sauer. "Coordination of microbial metabolism." Nature Reviews Microbiology 12, no. 5 (March 24, 2014): 327–40. http://dx.doi.org/10.1038/nrmicro3238.

Texte intégral
Styles APA, Harvard, Vancouver, ISO, etc.
10

Ash, Caroline. "Microbial entrainment of metabolism." Science 365, no. 6460 (September 26, 2019): 1414.10–1416. http://dx.doi.org/10.1126/science.365.6460.1414-j.

Texte intégral
Styles APA, Harvard, Vancouver, ISO, etc.
Plus de sources

Thèses sur le sujet "Microbial metabolism"

1

Burgess, Mary Catherine. "Insights into microbial metabolism." Thesis, Montana State University, 2012. http://etd.lib.montana.edu/etd/2012/burgess/BurgessMC0512.pdf.

Texte intégral
Résumé :
Nitrogen fixation (catalyzed by the enzyme nitrogenase), cellular respiration (completed through the Tricarboxylic Acid (TCA) cycle) and mercury detoxification (through mercury methylation) are three metabolic processes used by a wide variety of microorganisms, but that also have far reaching impacts on nutrient cycling in the environment. Roseiflexus castenholzii has been found to have a unique nitrogenase gene cluster encoding several nitrogenase homologs, including the structural proteins NifH and NifDK and the radical SAM protein, NifB, necessary for cofactor biosynthesis. However, the genome of R. castenholzii lacks the suite of nitrogenase accessory proteins necessary for nitrogen fixation. To investigate the metabolic role of these nitrogenase homologs, expression and purification protocols were developed that aid in the biochemical characterization of these proteins. Synechococcus sp. PCC 7002 encodes three novel TCA proteins, contrary to previous studies that indicated these phototrophs have incomplete TCA cycles. Expression, purification and preliminary crystallization trials were completed on the three novel TCA proteins in order to gain insight into the structure of the proteins which will elucidate the mechanism of each novel enzyme and provide evidence into the novel TCA cycle utilized by these cyanobacteria. The third project presented examines the role of microorganisms in metabolizing mercury, producing methylmercury and providing an entry point for methylmercury into the food chain in Yellowstone National Park (YNP). In this project, environmental samples were enriched for a sulfate reducing organism and a culture containing three sulfate reducing bacteria (SRB) has been established. The SRB that are present and active in the enrichment samples are known to reduce sulfate and may be responsible for the presence of methyl mercury in algal mats that bioaccumulates through the food chain in YNP. The enrichment of SRB in this culture will enable the identification and characterization of the organisms that are capable of methylating mercury in hydrothermal systems. Collectively, the results presented herein increase the knowledge base of three metabolic processes used by microorganisms: nitrogen fixation, cellular respiration through the TCA cycle and mercury detoxification; these results will contribute to a broader understanding of how these processes have evolved and their impacts on the environment.
Styles APA, Harvard, Vancouver, ISO, etc.
2

Patterson, Andrea Jennifer. "Microbial metabolism of organophosphonates." Thesis, University of Ulster, 2001. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.232856.

Texte intégral
Styles APA, Harvard, Vancouver, ISO, etc.
3

Lister, Diane Lorraine. "The microbial metabolism of cocaine." Thesis, University of Cambridge, 1995. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.390042.

Texte intégral
Styles APA, Harvard, Vancouver, ISO, etc.
4

Griffiths, David A. "Microbial mimicry of mammalian drug metabolism." Thesis, Cranfield University, 1990. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.385132.

Texte intégral
Styles APA, Harvard, Vancouver, ISO, etc.
5

Hansman, Roberta Lynn. "Microbial metabolism in the deep ocean." Diss., Connect to a 24 p. preview or request complete full text in PDF format. Access restricted to UC campuses, 2008. http://wwwlib.umi.com/cr/ucsd/fullcit?p3324933.

Texte intégral
Résumé :
Thesis (Ph. D.)--University of California, San Diego, 2008.<br>Title from first page of PDF file (viewed November 14, 2008). Available via ProQuest Digital Dissertations. Vita. Includes bibliographical references.
Styles APA, Harvard, Vancouver, ISO, etc.
6

Ohshiro, Takashi. "MICROBIAL SULFUR METABOLISM OF HETEROCYCLIC SULFUR COMPOUNDS." Kyoto University, 1996. http://hdl.handle.net/2433/78073.

Texte intégral
Styles APA, Harvard, Vancouver, ISO, etc.
7

Chandrasekaran, Appavu. "Microbial and human metabolism of cardiac glycosides /." The Ohio State University, 1986. http://rave.ohiolink.edu/etdc/view?acc_num=osu1487265555441466.

Texte intégral
Styles APA, Harvard, Vancouver, ISO, etc.
8

Pires, Aline Mara Barbosa. "Estudos metabolicos para otimização de condições nutricionais e de cultivo para produção microbiana de acido hialuronico." [s.n.], 2009. http://repositorio.unicamp.br/jspui/handle/REPOSIP/267027.

Texte intégral
Résumé :
Orientador: Maria Helena Andrade Santana<br>Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Engenharia Quimica<br>Made available in DSpace on 2018-08-14T16:51:23Z (GMT). No. of bitstreams: 1 Pires_AlineMaraBarbosa_D.pdf: 5667585 bytes, checksum: 99be814ed0f4b52809cad017f91235eb (MD5) Previous issue date: 2009<br>Resumo: Neste trabalho, estudou-se a otimização da produção de ácido hialurônico (HA) por cultivo de Streptococcus zooepidemicus em batelada, com base nas alterações metabólicas ao longo do cultivo. Ás condições ambientais estudadas foram a concentração inicial de glicose, controle do pH, íons minerais e fonte de nitrogênio orgânico. Nos cultivos em frascos, a concentração inicial de glicose não alterou nem o crescimento celular nem a produção de HA. Entretanto, no cultivo em biorreator sem o controle do pH, ambos foram fortemente dependentes da concentração inicial de glicose, com maior produção de HA (1,21 g.L-1) no cultivo realizado em meio com 25 g.L-1 glicose. Tal condição nutricional foi a única que apresentou maior conversão de glicose em HA (YHA/S) do que conversão de glicose em massa celular (YX/S). O controle do pH ao longo do cultivo com 25 g.L-1 glicose resultou em maior produtividade de células (0,21 g.L-1.h-1) e de HA (0,10 g.L-1.h-1). apesar dos menores rendimentos em relação à glicose. A combinação desses resultados relaciona o maior direcionamento da fonte de carbono para HA do que para células a uma resposta do microrganismo ao stress ácido ocorrido no cultivo sem controle do pH. Uma análise da distribuição dos fluxos metabólicos nas condições ambientais estudadas demonstrou que as alterações na via de produção de HA foram mais relacionadas à distribuição dos fluxos para os açúcares precursores da síntese do polímero que à disponibilidade de energia (ATP) ou potencial redutor (NADH/NAD+) das células. A total suplementação do meio de cultura com íons minerais (K+, Mg++, Na+, Fe++, Ca++, Mn++, Zn++ e Cu++) foi benéfica para o crescimento celular, porém não alterou a produção de HA de forma significativa. O estudo demonstrou ainda que a qualidade do polímero produzido pode ser modulada pela suplementação do meio com íons minerais. As propriedades reológicas do HA com baixo teor de proteína (0.44 g.g-1) e massa molar média de 4.0 x 106 Da demonstraram elevada densidade de emaranhamento das cadeias devido à alta dependência do módulo elástico com a concentração e desvios da viscosidade complexa com relação à regra de Cox-Merz. O estudo de meios alternativos contendo derivados agroindustriais demonstrou maiores concentrações de HA em meios contendo extrato de levedura como fonte de nitrogênio. Este conjunto de resultados contribui para a otimização da produção de HA, assim como para um melhor entendimento do metabolismo do Streptococcus zooepidemicus.<br>Abstract: In this work, h was studied the optimization of HA production by hatch culture of Streptococcus zooepidemicus, with focus on the metabolic changes along cultivation. The environmental conditions studied were the initial glucose concentration, pH control, mineral ions and organic nitrogen source. In flask cultivations, the initial glucose concentration had no influence on the amounts of either the biomass or the MA produced. However, in bioreactor cultivations, at non-controlled pH. both were strongly dependent on the initial glucose concentration. The highest HA concentration (1.21 g.L-1) was obtained from 25 g.L-1 glucose, which was the only cultivation where the conversion of glucose to HA (YHA/S) was higher than the one of glucose to biomass (YX/S). Not only did the pH control along cultivation result in higher cell productivity (0.21 g.L-1.h-1), but also in the HA productivity (0.10 g.L-1.h-1), However, the HA and cell yields from glucose were lower. The combination of these results relates the higher direction of the carbon source to the HA synthesis at the expenses of the cell growth to a microbial response to the acid stress observed in non-controlled pH. An analysis of the metabolic flux distribution in the environmental conditions studied shows that the changes in the HA production pathway were more related to die distributions of duxes 10 the precursors of HA synthesis than to the energy availability (ATP) or redox slate (NADH/NAD+) of the cells. The total supplementation of the culture medium with ions was beneficial to die cell growth. However, if did not have any influence on the HA production. Moreover, the results showed that the HA quality may be modulated through the mineral ion supplementation. The rheological properties of HA with low protein content (0.44 g.g-1) and average molecular weight of 4.0 x 106 Da showed the high entanglements density of the HA chains due to the high storage modulus concentration dependence as well as to the complex viscosity deviations with respect to the Cox - Merz rule. Alternative media containing agricultural resources derivates were studied. The higher HA concentrations were produced in media whose organic nitrogen source was yeast extract. This set of results contributes not only to the optimization of the HA production, but also to a better understanding of the Streptococcus zooepidemicus metabolism.<br>Doutorado<br>Desenvolvimento de Processos Biotecnologicos<br>Doutor em Engenharia Química
Styles APA, Harvard, Vancouver, ISO, etc.
9

Johnson, Winifred M. Ph D. Massachusetts Institute of Technology. "Linking microbial metabolism and organic matter cycling through metabolite distributions in the ocean." Thesis, Massachusetts Institute of Technology, 2017. http://hdl.handle.net/1721.1/108909.

Texte intégral
Résumé :
Thesis: Ph. D., Joint Program in Oceanography/Applied Ocean Science and Engineering (Massachusetts Institute of Technology, Department of Earth, Atmospheric, and Planetary Sciences; and the Woods Hole Oceanographic Institution), 2017.<br>Cataloged from PDF version of thesis.<br>Includes bibliographical references.<br>Key players in the marine carbon cycle are the ocean-dwelling microbes that fix, remineralize, and transform organic matter. Many of the small organic molecules in the marine carbon pool have not been well characterized and their roles in microbial physiology, ecological interactions, and carbon cycling remain largely unknown. In this dissertation metabolomics techniques were developed and used to profile and quantify a suite of metabolites in the field and in laboratory experiments. Experiments were run to study the way a specific metabolite can influence microbial metabolite output and potentially processing of organic matter. Specifically, the metabolic response of the heterotrophic marine bacterium, Ruegeria pomeroyi, to the algal metabolite dimethylsulfoniopropionate (DMSP) was analyzed using targeted and untargeted metabolomics. The manner in which DMSP causes R. pomeroyi to modify its biochemical pathways suggests anticipation by R. pomeroyi of phytoplankton-derived nutrients and higher microbial density. Targeted metabolomics was used to characterize the latitudinal and vertical distributions of particulate and dissolved metabolites in samples gathered along a transect in the Western Atlantic Ocean. The assembled dataset indicates that, while many metabolite distributions co-vary with biomass abundance, other metabolites show distributions that suggest abiotic, species specific, or metabolic controls on their variability. On sinking particles in the South Atlantic portion of the transect, metabolites possibly derived from degradation of organic matter increase and phytoplankton-derived metabolites decrease. This work highlights the role DMSP plays in the metabolic response of a bacterium to the environment and reveals unexpected ways metabolite abundances vary between ocean regions and are transformed on sinking particles. Further metabolomics studies of the global distributions and interactions of marine biomolecules promise to provide new insights into microbial processes and metabolite cycling.<br>by Winifred M. Johnson.<br>Ph. D.
Styles APA, Harvard, Vancouver, ISO, etc.
10

Newbold, Charles James. "Microbial metabolism of lactic acid in the rumen." Thesis, University of Glasgow, 1985. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.235529.

Texte intégral
Styles APA, Harvard, Vancouver, ISO, etc.
Plus de sources

Livres sur le sujet "Microbial metabolism"

1

Dahl, Christiane, and Cornelius G. Friedrich, eds. Microbial Sulfur Metabolism. Berlin, Heidelberg: Springer Berlin Heidelberg, 2008. http://dx.doi.org/10.1007/978-3-540-72682-1.

Texte intégral
Styles APA, Harvard, Vancouver, ISO, etc.
2

Christiane, Dahl, and Friedrich Cornelius G, eds. Microbial sulfur metabolism. Berlin: Springer, 2008.

Trouver le texte intégral
Styles APA, Harvard, Vancouver, ISO, etc.
3

Spormann, Alfred M. Principles of Microbial Metabolism and Metabolic Ecology. Cham: Springer International Publishing, 2023. http://dx.doi.org/10.1007/978-3-031-28218-8.

Texte intégral
Styles APA, Harvard, Vancouver, ISO, etc.
4

Caldwell, Daniel R. Microbial physiology and metabolism. 2nd ed. Belmont, Calif: Star, 1999.

Trouver le texte intégral
Styles APA, Harvard, Vancouver, ISO, etc.
5

Patterson, Andrea Jennifer. Microbial metabolism of organophosphonates. [S.l: The Author], 2001.

Trouver le texte intégral
Styles APA, Harvard, Vancouver, ISO, etc.
6

K, Poole Robert, Dow Crawford S, and Society for General Microbiology. Cell Biology Group., eds. Microbial gas metabolism: Mechanistic, metabolic, and biotechnological aspects. London: Published for the Society for General Microbiology by Academic Press, 1985.

Trouver le texte intégral
Styles APA, Harvard, Vancouver, ISO, etc.
7

Stolz, John F., and Ronald S. Oremland, eds. Microbial Metal and Metalloid Metabolism. Washington, DC, USA: ASM Press, 2011. http://dx.doi.org/10.1128/9781555817190.

Texte intégral
Styles APA, Harvard, Vancouver, ISO, etc.
8

Winkelmann, Günther, and Carl J. Carrano. Transition Metals in Microbial Metabolism. London: CRC Press, 2022. http://dx.doi.org/10.1201/9781003211129.

Texte intégral
Styles APA, Harvard, Vancouver, ISO, etc.
9

Arora, Pankaj Kumar, ed. Microbial Metabolism of Xenobiotic Compounds. Singapore: Springer Singapore, 2019. http://dx.doi.org/10.1007/978-981-13-7462-3.

Texte intégral
Styles APA, Harvard, Vancouver, ISO, etc.
10

Günther, Winkelmann, and Carrano Carl J, eds. Transition metals in microbial metabolism. Amsterdam: Harwood Academic Publishers, 1997.

Trouver le texte intégral
Styles APA, Harvard, Vancouver, ISO, etc.
Plus de sources

Chapitres de livres sur le sujet "Microbial metabolism"

1

Spormann, Alfred M. "Microbial Energetics." In Principles of Microbial Metabolism and Metabolic Ecology, 35–57. Cham: Springer International Publishing, 2023. http://dx.doi.org/10.1007/978-3-031-28218-8_3.

Texte intégral
Styles APA, Harvard, Vancouver, ISO, etc.
2

Spormann, Alfred M. "Microbial Kinetics." In Principles of Microbial Metabolism and Metabolic Ecology, 73–97. Cham: Springer International Publishing, 2023. http://dx.doi.org/10.1007/978-3-031-28218-8_5.

Texte intégral
Styles APA, Harvard, Vancouver, ISO, etc.
3

Hahn-Hägerdal, Bärbel, and Neville Pamment. "Microbial Pentose Metabolism." In Proceedings of the Twenty-Fifth Symposium on Biotechnology for Fuels and Chemicals Held May 4–7, 2003, in Breckenridge, CO, 1207–9. Totowa, NJ: Humana Press, 2004. http://dx.doi.org/10.1007/978-1-59259-837-3_97.

Texte intégral
Styles APA, Harvard, Vancouver, ISO, etc.
4

Hausinger, Robert P. "Microbial Nickel Metabolism." In Biochemistry of Nickel, 181–201. Boston, MA: Springer US, 1993. http://dx.doi.org/10.1007/978-1-4757-9435-9_7.

Texte intégral
Styles APA, Harvard, Vancouver, ISO, etc.
5

Tiquia-Arashiro, Sonia M. "Microbial CO Metabolism." In Thermophilic Carboxydotrophs and their Applications in Biotechnology, 5–9. Cham: Springer International Publishing, 2014. http://dx.doi.org/10.1007/978-3-319-11873-4_2.

Texte intégral
Styles APA, Harvard, Vancouver, ISO, etc.
6

Wall, Judy D., Adam P. Arkin, Nurgul C. Balci, and Barbara Rapp-Giles. "Genetics and Genomics of Sulfate Respiration in Desulfovibrio." In Microbial Sulfur Metabolism, 1–12. Berlin, Heidelberg: Springer Berlin Heidelberg, 2008. http://dx.doi.org/10.1007/978-3-540-72682-1_1.

Texte intégral
Styles APA, Harvard, Vancouver, ISO, etc.
7

Chan, Leong-Keat, Rachael Morgan-Kiss, and Thomas E. Hanson. "Sulfur Oxidation in Chlorobium tepidum (syn. Chlorobaculum tepidum): Genetic and Proteomic Analyses." In Microbial Sulfur Metabolism, 117–26. Berlin, Heidelberg: Springer Berlin Heidelberg, 2008. http://dx.doi.org/10.1007/978-3-540-72682-1_10.

Texte intégral
Styles APA, Harvard, Vancouver, ISO, etc.
8

Stout, Jan, Lina De Smet, Bjorn Vergauwen, Savvas Savvides, and Jozef Van Beeumen. "Structural Insights into Component SoxY of the Thiosulfate-Oxidizing Multienzyme System of Chlorobaculum thiosulfatiphilum." In Microbial Sulfur Metabolism, 127–38. Berlin, Heidelberg: Springer Berlin Heidelberg, 2008. http://dx.doi.org/10.1007/978-3-540-72682-1_11.

Texte intégral
Styles APA, Harvard, Vancouver, ISO, etc.
9

Friedrich, Cornelius G., Armin Quentmeier, Frank Bardischewsky, Dagmar Rother, Grazyna Orawski, Petra Hellwig, and Jürg Fischer. "Redox Control of Chemotrophic Sulfur Oxidation of Paracoccus pantotrophus." In Microbial Sulfur Metabolism, 139–50. Berlin, Heidelberg: Springer Berlin Heidelberg, 2008. http://dx.doi.org/10.1007/978-3-540-72682-1_12.

Texte intégral
Styles APA, Harvard, Vancouver, ISO, etc.
10

Kappler, Ulrike. "Bacterial Sulfite-Oxidizing Enzymes – Enzymes for Chemolithotrophs Only?" In Microbial Sulfur Metabolism, 151–69. Berlin, Heidelberg: Springer Berlin Heidelberg, 2008. http://dx.doi.org/10.1007/978-3-540-72682-1_13.

Texte intégral
Styles APA, Harvard, Vancouver, ISO, etc.

Actes de conférences sur le sujet "Microbial metabolism"

1

Leach, David G., Wei Wang, Chao Yan, Dillon Mattis, Ron MacLeod, and Wei Wei. "Molecular Deep Dive into Oilfield Microbiologically Influenced Corrosion: a Detailed Case Study of MIC Failure Analysis in an Unconventional Asset." In CONFERENCE 2022, 1–11. AMPP, 2022. https://doi.org/10.5006/c2022-17948.

Texte intégral
Résumé :
Abstract This work details a microbiologically influenced corrosion (MIC) failure analysis case study for a produced water pipeline. A pipeline in a shale and tight asset experienced heavy corrosion and ultimate failure within a 7-month period, with estimated corrosion rate at 161 mils per year (MPY), or 4.1 mm per year (MMPY). Upon removal by the inspection team, heavy white deposit buildup (a suspected microbial biofilm) was observed directly associated with the corrosion failure on top of a black scale underlayer. Detailed assessments were performed using ATP photometry, qPCR speciation, and 16S rRNA gene sequencing to profile the microbial population present, which was dominated by high -risk anaerobic microbial strains such as sulfate-reducing bacteria and methanogens. Scale analysis confirmed iron carbonate and iron sulfides associated with microbial iron metabolism and corrosion, and scanning electron microscopy explored surface morphology. This study will lay out detailed root cause analysis and include best practices for MIC diagnosis and recommendations for future prediction and prevention in oilfield assets.
Styles APA, Harvard, Vancouver, ISO, etc.
2

Williams, Terry M. "The Mechanism of Action of Isothiazolone Biocides." In CORROSION 2006, 1–17. NACE International, 2006. https://doi.org/10.5006/c2006-06090.

Texte intégral
Résumé :
Abstract Isothiazolone biocides have proven efficacy and performance for microbial control in a variety of industrial water treatment applications. Understanding the mechanism of action of industrial biocides is important in optimizing their use and combating resistance if encountered. Isothiazolones utilizes a two-step mechanism involving rapid inhibition (minutes) of growth and metabolism, followed by irreversible cell damage resulting in loss of viability (hours). Cells are inhibited by disruption of the metabolic pathways involving dehydrogenase enzymes. Critical physiological functions are rapidly inhibited in microbes, including growth, respiration (oxygen consumption), and energy generation (ATP synthesis). Cell death results from the destruction of protein thiols and production of free radicals. The rate and extent of killing may be enhanced by various adjuvants including surfactants. This unique mechanism results in a broad spectrum of activity, low use levels, and difficulty in attaining resistance.
Styles APA, Harvard, Vancouver, ISO, etc.
3

Mand, Jaspreet, Gerrit Voordouw, Heike Hoffmann, and Michael Horne. "Linking Sulfur Cycling and MIC in Offshore Water Transporting Pipelines." In CORROSION 2016, 1–12. NACE International, 2016. https://doi.org/10.5006/c2016-07578.

Texte intégral
Résumé :
Abstract Microbial activities in oil and gas operations cause souring, the production of sulfide by sulfate-reducing bacteria (SRB), and microbiologically-influenced corrosion (MIC). MIC may be especially severe in systems were several different types of fluids are mixed together, as this may provide a variety of nutrients for microbial growth. We have studied samples from an offshore production site and an onshore terminal for separation, crude oil storage, effluent treatment and disposal. We have investigated the samples using chemical analyses, culture-based microbial counts and molecular DNA-based techniques (pyrosequencing) to obtain whole microbial community composition. We found that (i) sulfate reduction by SRB (Desulfovibrio, Desulfobacterium, Desulfobacter) leads to the formation of sulfide, that (ii) sulfide is reoxidized to form elemental sulfur both abiotically and through the metabolism of sulfide-oxidizing bacteria (Sulfurimonas, Arcobacter) and that (iii) sulfur is converted back to sulfide by sulfur-reducing bacteria (S0RB, Desulfuromonas, Desulfuromusa), completing the sulfur cycle. Samples from these systems have significant sulfate, sulfide and sulfur (S8) concentrations and reactions (i) to (iii) can be demonstrated to occur. We find that the presence of elemental sulfur, which is increased by reactions (i) and (ii) and decreased by reaction (iii) gives rise to considerably increased corrosion risk towards steel infrastructure.
Styles APA, Harvard, Vancouver, ISO, etc.
4

Walsh, Dan, Eric Willis, Tom VanDiepen, and Jeff Sanders. "The Effect of Microstructure on Microbial Interaction with Metals - Accent Welding." In CORROSION 1994, 1–19. NACE International, 1994. https://doi.org/10.5006/c1994-94612.

Texte intégral
Résumé :
Abstract Microbes affect the degradation process in many ways, the relationship between microstructure and microbial interaction has often been overlooked. This is particularly true in welded structures, where the microstructure of the fusion zone and heat affected zone can create environments that support microbial metabolism. This paper will present the results of several investigations involving stainless steels, aluminum alloys, and low alloy steels. It will also address the affect of welding on MIC susceptibility in these materials. It is not meant to be a review of MIC study in general, nor is it an extensive review of a particular facet of MIC research - it is a review of MIC work accomplished by researchers in our laboratory and associated laboratories - with a focus on the relationship between metallurgical microstructure and MIC. Microbes seem to accelerate the corrosion process - locating susceptible areas, fixing anodic sites, and producing or accumulating chemical species that promote corrosion. Alloy composition and microstructure play a crucial role in the corrosion process, but surface geometry and thermomechanical history are also critical.
Styles APA, Harvard, Vancouver, ISO, etc.
5

Yang, Yan, Rajan Ambat, Riccardo Rizzo, and Magdalena Rogowska. "Multipronged Characterization of Scales and Corrosion on L80 Steel in the Presence of Microorganism." In CORROSION 2019, 1–12. NACE International, 2019. https://doi.org/10.5006/c2019-13226.

Texte intégral
Résumé :
Abstract Scale deposit and corrosion attack on the L80 steel were observed using several analytical techniques, including 3D scanning microscopy, scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS) and X-ray diffraction (XRD). This multipronged approach provided a more complete image and component of the species found on the steel surface. Cross-sectional SEM examinations showed the distribution and characteristic of scale. The results of EDS revealed that Fe, O and S were the most abundant elements in the scale layer, and the component analysis results showed that iron hydroxides, iron sulfide, barium sulfate, and calcium carbonate were deposited on the steel surface. The corrosion investigation shows that the steel surface has been seriously corroded; pitting corrosion, microbial corrosion and other forms are found. Pitting corrosion occurring on the steel surface under the comprehensive action of the metabolism of microorganism was observed by SEM. Morphology differences between microbial corrosion pits and non-microbial corrosion pits were studied. Microorganism pits displayed many tiny pores that crammed closely under high magnification. The research results have good reference value and guiding significance for the establishment of scale models and the selection of corrosion protection methods.
Styles APA, Harvard, Vancouver, ISO, etc.
6

Ashar, Khoirun Nisa, Venty Suryanti, Abbilah Ero Mahdhani, Vicky Ahava Ferdinansyah, and Alifiananda Rahmatul Dafa Kesuma. "Utilization of <i>Escherichia coli</i> and Lapindo Mud on Microbial Fuel Cells (MFCs) System." In 8th International Conference on Advanced Material for Better Future, 41–48. Switzerland: Trans Tech Publications Ltd, 2025. https://doi.org/10.4028/p-ozje64.

Texte intégral
Résumé :
This research investigates the utilization of Escherichia coli and Lapindo mud in a two-chamber Microbial Fuel Cells (MFCs) series. MFCs are tools that convert chemical energy into electrical energy with the help of catalytic reactions from microorganisms. This research uses a dual chamber reactor connected by a salt bridge, with graphite electrodes placed in each chamber and connected by copper cables. Lapindo mud contains heavy metals, such as Cu and Pb. In small amounts, heavy metals required for maintaining various biochemical and physiological functions in living organisms, but in greater amounts they can become hazardous or toxic. Heavy metals are major environmental contaminants. The toxicity of heavy metals is an important issue for ecological, evolutionary, nutritional, and environmental reasons. Lapinda mud was placed in the cathode chamber to produce electricity. The cathode chamber was packed using a mixture of Lapindo mud, ammonium chloride, and sulfuric acid. Various amount Lapindo mud was applied, such as 35, 45, and 55 g. On the anode side, E. coli bacteria was used as microorganisms under anaerobic conditions with glucose as a substrate. E. coli undergoes metabolism, producing NAD+ to transfer electrons to produce electricity. Electrical voltage measurements are carried out periodically every hour for 35 h. The best performance was achieved when 55 g of Lapindo mud was used. The exponential phase of E. coli growth occurred at 10 h of cultivation, resulting in a spike in electricity production of 228.13 mV. After reaching the stationary phase of bacterial growth, the electricity generation remained constant for 19-30 h, which reached 342.9 mV; 0.01 mA, 0.034167 watts.
Styles APA, Harvard, Vancouver, ISO, etc.
7

Amaya, Hisashi, and Hideaki Miyuki. "Laboratory Reproduction of Potential Ennoblement of Stainless Steels in Natural Seawater." In CORROSION 1999, 1–15. NACE International, 1999. https://doi.org/10.5006/c1999-99168.

Texte intégral
Résumé :
Abstract The localized corrosion susceptibility of stainless steels, such as type 316L, immersed in natural seawater is higher than those in synthetic seawater. It is widely observed that the corrosion potential of stainless steels in natural seawater becomes noble over +0.3V vs SCE. This phenomenon is caused by the influence of the microorganisms in the natural seawater, and therefore it is considered as Microbially Influenced Corrosion (MIC). In this paper, the laboratory reproduction of the corrosion potential ennoblement was examined on the basis of the metabolize of aerobic bacteria (pH, dissolved oxygen and metabolite). The electrochemical measurements in natural seawater and synthetic seawater with bacterial mediums were carried out. The corrosion potential of stainless steels became noble in only natural seawater, and cathodic current density increased around corrosion potential, these results suggest that the presence of oxidizer on the metal surface which has higher redox potential than that of oxygen. As the corrosion potential became noble during the logarithmic phase of bacterial growth in the result of the examination with isolated bacteria, it is suggested that the aerobic metabolism of bacteria effects the ennoblement of corrosion potential. The ennoblement was also reproduced in laboratory by the addition of oxidase simulated the metabolism of aerobic bacteria. The oxidase produced the peroxide by the reduction of oxygen which has higher redox potential than that of oxygen, therefore it is considered that the corrosion potential ennoblement is caused by the peroxide generated by the metabolism of aerobic bacteria included in the biofilm formed on the surface of the stainless steels in natural seawater.
Styles APA, Harvard, Vancouver, ISO, etc.
8

Liduino, Vitor Silva, Magali Christe Cammarota, and Eliana Flávia Camporese Sérvulo. "Electrochemically Active Biofilm on AISI 1020 Steel and Its Corrosion Potential." In LatinCORR 2023, 35–37. AMPP, 2023. https://doi.org/10.5006/lac23-20888.

Texte intégral
Résumé :
Electroactive biofilms provide environments conducive to the occurrence of microbiologically influenced corrosion (MIC) in several industrial sectors. There are many distinct MIC mechanisms associated with different microbial groups and metabolism types. Most published research studies on MIC focus on bacteria, where sulfate-reducing bacteria (SRB) have the largest impact on corrosion because sulfate is widely distributed in anoxic environments, such as offshore oil reservoirs. This study investigated the role of an oilfield SRB-consortium in the AISI 1020 carbon steel corrosion immersed in hypersaline seawater (10% NaCl w/m) with low dissolved oxygen (&amp;gt;2 mg/L). This steel is globally used to build oil and gas industry facilities exposed to both onshore and offshore sites due to its low cost and good corrosion resistance. Each microcosm consisted of 100 mL seawater and one suspended metallic coupon of 6 cm2 total surface area. Three identical microcosms were performed. Simultaneously, abiotic control assays without microbial consortium were also executed. The assays were analysed by weight loss method and scanning electron microscopy (SEM) after 10 days at 40°C. Additionally, SRB counts in the hypersaline seawater at diferent times are done. The planktonic population increased slow and its peak at 9.5× 106 MPN/mL appeared at day 10. This result suggest that the increased salt content was not an inhibiting factor since the SRB consortia grew well and remained metabolically active throughout the assay. Corrosion rates are shown in Table 1. The abiotic condition must have improved the corrosion rate because of the large amount of chloride ions (Cl−) in the hypersaline seawater (10% w/v salinity). Cl− enhances the electrical conductivity of aqueous solutions and consequently boosts the velocity of oxidation and reduction reactions of the corrosive process. Thus, it proceeds an homogeneous degradation over the entire surface area causing signifcant mass loss and well-proportioned corrosion rate. On the other hand, SRB-MIC consumes only a relatively small amount (mass) of material due to the localized corrosion (pits), corroborating the low corrosion rate. Many pits were detected in the steel surface with a maximum depth of 33 μm; it was 86% deeper than the maximum pit depth in abiotic condition.
Styles APA, Harvard, Vancouver, ISO, etc.
9

Xiang, Yuchen. "Research on Optimization of Microbial Metabolic Network Model and its Application in Metabolite Synthesis." In 2024 4th International Conference on Computer Science and Blockchain (CCSB), 250–55. IEEE, 2024. http://dx.doi.org/10.1109/ccsb63463.2024.10735559.

Texte intégral
Styles APA, Harvard, Vancouver, ISO, etc.
10

Corrin, Edward, and Terry M. Williams. "A Case Study Evaluating a Co-Injection Biocide Treatment of Hydraulic Fracturing Fluids Utilized in Oil and Gas Production." In CORROSION 2015, 1–15. NACE International, 2015. https://doi.org/10.5006/c2015-05998.

Texte intégral
Résumé :
Abstract The recovery of petroleum resources from previously untapped shale reserves significantly impacts the global energy market. Effective management of limited water resources and control of microbial contamination in all process fluids are crucial to the sustained quality of production fluids. Microbiological contamination in untreated waters is recognized in the oil and gas industry as posing a high risk of production fluid souring by allowing the growth and metabolism of sulfate reducers. In addition to hydraulic source water contamination, it is expected that microbes can be introduced into shales at the time of drilling, necessitating the treatment of source waters to target existing downhole contamination. A two-part biocide treatment strategy has been extensively evaluated in controlled laboratory studies. The synergistic combination treatment involves the co-injection of dimethyl oxazolidine (DMO), along with the industry benchmark glutaraldehyde (GLUT). Laboratory testing showed a combination of treatments applied at 1:1 to 1:4 GLUT to DMO active ratios were highly synergistic against bacteria. This ratio provided a rapid kill of sulfate-reducing bacteria (SRB) and acid-producing bacteria (APB), as well as extended control in downhole conditions. Testing conditions were designed to simulate downhole conditions in a North American shale play; subsequently, the shale play was selected for field trials. A field-wide application of GLUT:DMO in the Niobrara formation was performed from 2012 to 2013. This case study reports 70 hydraulically fractured wells comprised from 25 well pads that received the GLUT/DMO combination treatment. The treatment was successful in maintaining low bacteria counts in the flowback/produced water, using liquid culture media (three positive SRB vials or less). Key advantages of this new treatment strategy include lower total biocide usage versus competitive biocides, an improved environmental (ecotoxicity) profile, enhanced performance at an alkaline pH, and compatibility with process additives.
Styles APA, Harvard, Vancouver, ISO, etc.

Rapports d'organisations sur le sujet "Microbial metabolism"

1

McKinlay, James B. Metabolism and Evolution of a Biofuel-Producing Microbial Coculture. Office of Scientific and Technical Information (OSTI), June 2018. http://dx.doi.org/10.2172/1459596.

Texte intégral
Styles APA, Harvard, Vancouver, ISO, etc.
2

Lovley, Derek R. Diagnosis of In Situ Metabolic State and Rates of Microbial Metabolism During In Situ Uranium Bioremediation with Molecular Techniques. Office of Scientific and Technical Information (OSTI), November 2012. http://dx.doi.org/10.2172/1097098.

Texte intégral
Styles APA, Harvard, Vancouver, ISO, etc.
3

Lovley, Derek R. Diagnosis of In Situ Metabolic State and Rates of Microbial Metabolism During In Situ Uranium Bioremediation with Molecular Techniques. Office of Scientific and Technical Information (OSTI), November 2012. http://dx.doi.org/10.2172/1055767.

Texte intégral
Styles APA, Harvard, Vancouver, ISO, etc.
4

Sarvaiya, Niral, and Vijay Kothari. Audible sound in form of music can influence microbial growth, metabolism, and antibiotic susceptibility. Cold Spring Harbor Laboratory, March 2016. http://dx.doi.org/10.1101/044776.

Texte intégral
Styles APA, Harvard, Vancouver, ISO, etc.
5

Konisky, J. International Symposium on Topics in Microbial Diversity, Metabolism, and Physiology. Final report, May 22--23, 1992. Office of Scientific and Technical Information (OSTI), July 1993. http://dx.doi.org/10.2172/10158099.

Texte intégral
Styles APA, Harvard, Vancouver, ISO, etc.
6

Hofmockel, Kirsten. Microbial drivers of global change at the aggregate scale: linking genomic function to carbon metabolism and warming. Office of Scientific and Technical Information (OSTI), June 2019. http://dx.doi.org/10.2172/1524429.

Texte intégral
Styles APA, Harvard, Vancouver, ISO, etc.
7

Droby, S., J. L. Norelli, M. E. Wisniewski, S. Freilich, A. Faigenboim, and C. Dardick. Microbial networks on harvested apples and the design of antagonistic consortia to control postharvest pathogens. Israel: United States-Israel Binational Agricultural Research and Development Fund, 2020. http://dx.doi.org/10.32747/2020.8134164.bard.

Texte intégral
Résumé :
We have demonstrated, at a global level, the existence of spatial variation in the fungal and bacterial composition of different fruit tissues. The composition, diversity and abundance varied in fruit harvested in different geographical locations and suggests a potential link between location and the type and rate of postharvest diseases that develop in each country. The global core microbiome of apple fruit was determined and found to be represented by several beneficial microbial taxa and accounted for a large fraction of the fruit microbial community. To further characterize apple fruit the microbiome after harvest, a detailed study was performed to evaluate effects of postharvest practices on the composition of the fruit peel. Microbiota. Results of this work conformed our findings that tissue-type is the main factor driving fungal and bacterial diversity and community composition on apple fruit. Both postharvest treatments and low temperature storage had a great impact on the fungal and bacterial diversity and community composition of these tissue types. Distinct spatial and temporal changes in the composition and diversity of the microbiota were observed in response to various postharvest management practices. Our results clearly indicated that apple fruit has a unique core microbiome that is universal. Analysis of the microbiome across Malus species indicates that the microbiome of domesticated apple has a higher diversity and abundance and is an admixture of the microbiome present in its wild progenitors, with clear evidence for introgression. These findings support the existence of co-evolution between Malus species and their microbiome during domestication. A network analysis of the metagenomics data was used to further elucidate functional differences between the microbiome of organic vs. conventional fruit. Our analysis predicted a link between Capnodiales and the degradation of aromatic compounds. Alternaria, a genus in the Capnodiales genus, is one of the main pathogens of stored apple fruit and was also abundant in our samples. The potential role of Alternaria in the degradation of aromatic compounds is in agreement with previous studies indicating a link between Alternaria and the metabolism of the aromatic compound, alphafarnesene38, a key volatile secreted by the fruit during maturation. A greater number of metabolic pathways related to plant defense substances (e.g. terpenoids and alkaloids) were identified in the microbiome of organic fruit samples, while more antibiotic-related metabolic pathways for compounds such as Erythromycin, Avermectin, Ansamycin, and Penicillin were present in the microbiome of apple fruit samples grown using conventional management practices.
Styles APA, Harvard, Vancouver, ISO, etc.
8

Minz, Dror, Stefan J. Green, Noa Sela, Yitzhak Hadar, Janet Jansson, and Steven Lindow. Soil and rhizosphere microbiome response to treated waste water irrigation. United States Department of Agriculture, January 2013. http://dx.doi.org/10.32747/2013.7598153.bard.

Texte intégral
Résumé :
Research objectives : Identify genetic potential and community structure of soil and rhizosphere microbial community structure as affected by treated wastewater (TWW) irrigation. This objective was achieved through the examination soil and rhizosphere microbial communities of plants irrigated with fresh water (FW) and TWW. Genomic DNA extracted from soil and rhizosphere samples (Minz laboratory) was processed for DNA-based shotgun metagenome sequencing (Green laboratory). High-throughput bioinformatics was performed to compare both taxonomic and functional gene (and pathway) differences between sample types (treatment and location). Identify metabolic pathways induced or repressed by TWW irrigation. To accomplish this objective, shotgun metatranscriptome (RNA-based) sequencing was performed. Expressed genes and pathways were compared to identify significantly differentially expressed features between rhizosphere communities of plants irrigated with FW and TWW. Identify microbial gene functions and pathways affected by TWW irrigation*. To accomplish this objective, we will perform a metaproteome comparison between rhizosphere communities of plants irrigated with FW and TWW and selected soil microbial activities. Integration and evaluation of microbial community function in relation to its structure and genetic potential, and to infer the in situ physiology and function of microbial communities in soil and rhizospere under FW and TWW irrigation regimes. This objective is ongoing due to the need for extensive bioinformatics analysis. As a result of the capabilities of the new PI, we have also been characterizing the transcriptome of the plant roots as affected by the TWW irrigation and comparing the function of the plants to that of the microbiome. *This original objective was not achieved in the course of this study due to technical issues, especially the need to replace the American PIs during the project. However, the fact we were able to analyze more than one plant system as a result of the abilities of the new American PI strengthened the power of the conclusions derived from studies for the 1ˢᵗ and 2ⁿᵈ objectives. Background: As the world population grows, more urban waste is discharged to the environment, and fresh water sources are being polluted. Developing and industrial countries are increasing the use of wastewater and treated wastewater (TWW) for agriculture practice, thus turning the waste product into a valuable resource. Wastewater supplies a year- round reliable source of nutrient-rich water. Despite continuing enhancements in TWW quality, TWW irrigation can still result in unexplained and undesirable effects on crops. In part, these undesirable effects may be attributed to, among other factors, to the effects of TWW on the plant microbiome. Previous studies, including our own, have presented the TWW effect on soil microbial activity and community composition. To the best of our knowledge, however, no comprehensive study yet has been conducted on the microbial population associated BARD Report - Project 4662 Page 2 of 16 BARD Report - Project 4662 Page 3 of 16 with plant roots irrigated with TWW – a critical information gap. In this work, we characterize the effect of TWW irrigation on root-associated microbial community structure and function by using the most innovative tools available in analyzing bacterial community- a combination of microbial marker gene amplicon sequencing, microbial shotunmetagenomics (DNA-based total community and gene content characterization), microbial metatranscriptomics (RNA-based total community and gene content characterization), and plant host transcriptome response. At the core of this research, a mesocosm experiment was conducted to study and characterize the effect of TWW irrigation on tomato and lettuce plants. A focus of this study was on the plant roots, their associated microbial communities, and on the functional activities of plant root-associated microbial communities. We have found that TWW irrigation changes both the soil and root microbial community composition, and that the shift in the plant root microbiome associated with different irrigation was as significant as the changes caused by the plant host or soil type. The change in microbial community structure was accompanied by changes in the microbial community-wide functional potential (i.e., gene content of the entire microbial community, as determined through shotgun metagenome sequencing). The relative abundance of many genes was significantly different in TWW irrigated root microbiome relative to FW-irrigated root microbial communities. For example, the relative abundance of genes encoding for transporters increased in TWW-irrigated roots increased relative to FW-irrigated roots. Similarly, the relative abundance of genes linked to potassium efflux, respiratory systems and nitrogen metabolism were elevated in TWW irrigated roots when compared to FW-irrigated roots. The increased relative abundance of denitrifying genes in TWW systems relative FW systems, suggests that TWW-irrigated roots are more anaerobic compare to FW irrigated root. These gene functional data are consistent with geochemical measurements made from these systems. Specifically, the TWW irrigated soils had higher pH, total organic compound (TOC), sodium, potassium and electric conductivity values in comparison to FW soils. Thus, the root microbiome genetic functional potential can be correlated with pH, TOC and EC values and these factors must take part in the shaping the root microbiome. The expressed functions, as found by the metatranscriptome analysis, revealed many genes that increase in TWW-irrigated plant root microbial population relative to those in the FW-irrigated plants. The most substantial (and significant) were sodium-proton antiporters and Na(+)-translocatingNADH-quinoneoxidoreductase (NQR). The latter protein uses the cell respiratory machinery to harness redox force and convert the energy for efflux of sodium. As the roots and their microbiomes are exposed to the same environmental conditions, it was previously hypothesized that understanding the soil and rhizospheremicrobiome response will shed light on natural processes in these niches. This study demonstrate how newly available tools can better define complex processes and their downstream consequences, such as irrigation with water from different qualities, and to identify primary cues sensed by the plant host irrigated with TWW. From an agricultural perspective, many common practices are complicated processes with many ‘moving parts’, and are hard to characterize and predict. Multiple edaphic and microbial factors are involved, and these can react to many environmental cues. These complex systems are in turn affected by plant growth and exudation, and associated features such as irrigation, fertilization and use of pesticides. However, the combination of shotgun metagenomics, microbial shotgun metatranscriptomics, plant transcriptomics, and physical measurement of soil characteristics provides a mechanism for integrating data from highly complex agricultural systems to eventually provide for plant physiological response prediction and monitoring. BARD Report
Styles APA, Harvard, Vancouver, ISO, etc.
9

TURICK, CHARLES. Microbial Metabolite Production for Accelerated Metal and Radionuclide Bioremediation (Microbial Metabolite Production Report). Office of Scientific and Technical Information (OSTI), September 2004. http://dx.doi.org/10.2172/835058.

Texte intégral
Styles APA, Harvard, Vancouver, ISO, etc.
10

Varga, Gabriella A., Amichai Arieli, Lawrence D. Muller, Haim Tagari, Israel Bruckental, and Yair Aharoni. Effect of Rumen Available Protein, Amimo Acids and Carbohydrates on Microbial Protein Synthesis, Amino Acid Flow and Performance of High Yielding Cows. United States Department of Agriculture, August 1993. http://dx.doi.org/10.32747/1993.7568103.bard.

Texte intégral
Résumé :
The effect of rumen available protein amino acids and carbohydrates on microbial protein synthesis, amino acid flow and performance of high yielding dairy cows was studied. A significant relationship between the effective degradabilities of OM in feedstuffs and the in vivo ruminal OM degradation of diets of dairy cows was found. The in situ method enabled the prediction of ruminal nutrients degradability response to processing of energy and nitragenous supplements. The AA profile of the rumen undegradable protein was modified by the processing method. In a continuous culture study total N and postruminal AA flows, and bacterial efficiency, is maximal at rumen degradable levels of 65% of the CP. Responses to rumen degradable non carbohydrate (NSC) were linear up to at least 27% of DM. Higher CP flow in the abomasum was found for cows fed high ruminally degradable OM and low ruminally degradable CP diet. It appeared that in dairy cows diets, the ratio of rumen degradable OM to rumenally degradable CP should be at least 5:1 in order to maximize postruminal CP flow. The efficiency of microbial CP synthesis was higher for diets supplemented with 33% of rumen undegradable protein, with greater amounts of bacterial AA reaching the abomasum. Increase in ruminal carbohydrate availability by using high moisture corn increased proportions of propionate, postruminal nutrients flow, postruminal starch digestibility, ruminal availability of NSC, uptake of energy substrates by the mammory gland. These modifications resulted with improvement in the utilization of nonessential AA for milk protein synthesis, in higher milk protein yield. Higher postruminal NSC digestibility and higher efficiency of milk protein production were recorded in cows fed extruded corn. Increasing feeding frequency increased flow of N from the rumen to the blood, reduced diurnal variation in ruminal and ammonia, and of plasma urea and improved postruminal NSC and CIP digestibility and total tract digestibilities. Milk and constituent yield increased with more frequent feeding. In a study performed in a commercial dairy herd, changes in energy and nitrogenous substrates level suggested that increasing feeding frequency may improve dietary nitrogen utilization and may shift metabolism toward more glucogenesis. It was concluded that efficiency of milk protein yield in high producing cows might be improved by an optimization of ruminal and post-ruminal supplies of energy and nitrogenous substrates. Such an optimization can be achieved by processing of energy and nitrogenous feedstuffs, and by increasing feeding frequency. In situ data may provide means for elucidation of the optimal processing conditions.
Styles APA, Harvard, Vancouver, ISO, etc.
Vous pouvez également être intéressé par les bibliographies sur le sujet « Microbial metabolism » pour d’autres types de sources :
Articles de revues Thèses Livres
Nous offrons des réductions sur tous les plans premium pour les auteurs dont les œuvres sont incluses dans des sélections littéraires thématiques. Contactez-nous pour obtenir un code promo unique!

Vers la bibliographie