Consulta: subjectFacets:"Anaerobiosis"
Registros recuperados: 9
Data/hora: 11/06/2024 11:36:36

Entrapment of anaerobic thermophilic and hyperthermophilic marine microorganisms in a gellan/xanthan matrix
Provedor de dados: 5
Autores: Landreau, M.; Duthoit, Frederique; Claeys-bruno, M.; Vandenabeele-trambouze, O.; Aubry, T.; Godfroy, Anne; Le Blay, Gwenaelle.
Aims  The aims of this study were (i) to develop a protocol for the entrapment of anaerobic (hyper)thermophilic marine micro-organisms; (ii) to test the use of the chosen polymers in a range of physical and chemical conditions and (iii) to validate the method with batch cultures. Methods and Results  The best conditions for immobilization were obtained at 80°C with gellan and xanthan gums. After 5-week incubation, beads showed a good resistance to all tested conditions except those simultaneously including high temperature (100°C), low NaCl (&lt;0∙5 mol l−1) and extreme pH (4/8). To confirm the method efficiency, batch cultures with immobilized Thermosipho sp. strain AT1272 and Thermococcus kodakarensis strain KOD1 showed an absence of detrimental effect...
Tipo: Text
Palavras-chave: (hyper)thermophilic marine micro-organisms; Anaerobiosis; Entrapment; Gellan; Immobilization; Xanthan.
Ano: 2016
URL: http://archimer.ifremer.fr/doc/00332/44352/44000.pdf

Cultivation of an immobilized (hyper)thermophilic marine microbial community in a bioreactor
Provedor de dados: 5
Autores: Landreau, M.; Duthoit, Frederique; Roussel, Erwan; Schonherr, S.; Georges, Myriam; Godfroy, Anne; Le Blay, G.
Cultivation in a bioreactor of immobilized deep-sea hydrothermal microbial community was tested in order to assess the stability and reactivity of this new system. A community composed of 8 hydrothermal strains was entrapped in a polymer matrix that was used to inoculate a continuous culture in a gas-lift bioreactor. The continuous culture was performed for 41 days at successively 60°C, 55°C, 60°C, 85°C and 60°C, at pH 6.5, in anaerobic condition and constant dilution rate. Oxic stress and pH variations were tested at the beginning of the incubation. Despite these detrimental conditions, 3 strains including 2 strict anaerobes were maintained in the bioreactor. High cell concentrations (3 × 108 cells mL−1) and high ATP contents were measured in both liquid...
Tipo: Text
Palavras-chave: Immobilization; Anaerobiosis; Marine (hyper)thermophiles; Continuous culture.
Ano: 2016
URL: http://archimer.ifremer.fr/doc/00347/45851/45516.pdf

Morphological and Phenological Responses of Eragrostis plana Nees and Eragrostis pilosa (L.) P. Beauv. Plants Subjected to Different Soil Moisture Conditions
Provedor de dados: 87
Autores: CARLOTO,B.W.; BURIOL,G.A.; DORNELLES,S.H.B.; TRIVISIOL,V.S.; PERIPOLLI,M.; ESCOBAR,O.S.
ABSTRACT: Experiments were run in a greenhouse where samples of Eragrostis pilosa and Eragrostis plana, species that infest rice crops, were subjected to three soil moisture conditions (50% of soil water retention capacity (WRC), 100% of WRC, 10 cm water depth), simulating three different environments (upland, lowland and irrigated rice farm, respectively), with the aim of studying how these conditions affect the morphology and vegetative cycle of these plants, by means of development and growth assessments. Results show that each species responds differently when subjected to varying amounts of water in the soil. Soaking the soil with 10 cm of water was the treatment that most negatively influenced the development of E. plana plants, reducing the...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Anaerobiosis; Soil; Waterlogging; Acclimatization; Grasses.
Ano: 2019
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-83582019000100176

Flooding effects in seedlings of Cytharexyllum myrianthum Cham. and Genipa americana L.: responses of two neotropical lowland tree species
Provedor de dados: 88
Autores: ANDRADE,ANTÔNIO CARLOS SILVA DE; RAMOS,FLAVIO NUNES; SOUZA,ALEXANDRE FADIGAS DE; LOUREIRO,MARTA BRUNO; BASTOS,RODRIGO.
Six-month-old seedlings of Cytharexyllum myrianthum and Genipa americana, two common tree species in different flood-prone areas in Brazil, were flooded for up to 90 days to compare their survival and growth responses under these conditions. Seedlings of both species were found to be relatively tolerant to flooding but growth responses changed according to treatment and plant species. Growth of G. americana was reduced by flooding, showing a decrease in root and leaf dry mass, root/shoot ratio and height, without showing any adaptive morphological changes. On the other hand, growth of C. myrianthum seedlings was stimulated under flooding conditions, showing an increase in root dry mass, root/shoot ratio, height, stem diameter and some morphological changes...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Anaerobiosis; Environmental stress; Growth; Hypoxia; Submergence.
Ano: 1999
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-84041999000500009

Iron oxidation on the surface of adventitious roots and its relation to aerenchyma formation in rice genotypes
Provedor de dados: 90
Autores: Holzschuh,Marquel Jonas; Carlos,Filipe Selau; Carmona,Felipe de Campos; Bohnen,Humberto; Anghinoni,Ibanor.
Establishment of the water layer in an irrigated rice crop leads to consumption of free oxygen in the soil which enters in a chemical reduction process mediated by anaerobic microorganisms, changing the crop environment. To maintain optimal growth in an environment without O2, rice plants develop pore spaces (aerenchyma) that allow O2 transport from air to the roots. Carrying capacity is determined by the rice genome and it may vary among cultivars. Plants that have higher capacity for formation of aerenchyma should theoretically carry more O2 to the roots. However, part of the O2 that reaches the roots is lost due to permeability of the roots and the O2 gradient created between the soil and roots. The O2 that is lost to the outside medium can react with...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Anaerobiosis; Oryza sativa L.; Pore spaces.
Ano: 2014
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-06832014000100018

The rates and players of denitrification, dissimilatory nitrate reduction to ammonia (DNRA) and anaerobic ammonia oxidation (anammox) in mangrove soils
Provedor de dados: 42
Autores: LUVIZOTTO,DANICE M.; ARAUJO,JULIANA E.; SILVA,MICHELE DE CÁSSIA P.; DIAS,ARMANDO C. F.; KRAFT,BEATE; TEGETMEYE,HALINA; STROUS,MARC; ANDREOTE,FERNANDO D.
Abstract Mangroves are ecosystems located in the transition zone between land and sea, characterized by periodic flooding that confer to its unique characteristics. Little is known about the transformation of nutrients that occur during the organic matter degradation in this system. In this study, we monitor the nitrogen transformations in soils from three mangroves with distinct levels of contamination using labeled 15NO3-. We also screened the mangroves metagenomes for the presence of genes that encode enzymes involved in denitrification (nirS, nirK, nosZ, norB and narG), anaerobic oxidation of ammonia (anammox) (hh, hao and hzo) and dissimilatory nitrate reduction to ammonium (DNRA) (nrfA). The transformations of 15NO3- indicated the balance of...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: N cycling; Anaerobiosis; Metagenome; Environmental contamination.
Ano: 2019
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0001-37652019000200503

Modification of pyruvate kinase and lactate dehydrogenase in foot muscle of the sea mussel Mytilus galloprovincialis under anaerobiosis and recovery
Provedor de dados: 56
The modification of pyruvate kinase (PK) and lactate dehydrogenase (LDH) activity in foot muscle of the mussel Mytilus galloprovincialis during exposure to air and recovery in water was investigated. In the course of exposure to air, the activity of these enzymes measured at high and low substrate concentrations showed successive increases and decreases. Returning the mussels to water after exposure to air affected enzyme activity in a manner similar to anaerobiosis. When measuring at saturated concentrations of substrates and substrate and coenzyme for PK and LDH, respectively, the maximum activation of PK (37%) was observed at 4 h of animal exposure to air, and for LDH (67%) at 6 h exposure to air. During 24 h of exposure of animals to air, PK activity...
Tipo: Info:eu-repo/semantics/other
Palavras-chave: Mytilus galloprovincialis; Muscle; Anaerobiosis; Pyruvate kinase; Lactate dehydrogenase; Property modification.
Ano: 1997
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-879X1997000300012

Use of photocatalytic reduction to hasten preparation of culture media for saccharolytic Clostridium species
Provedor de dados: 58
Autores: Fukushima,Romualdo S.; Weimer,Paul J.; Kunz,Daniel A.
Cysteine is the preferred reducing agent used in the preparation of culture media for the growth of many strictly anaerobic microorganisms; however, redox potential reduction of cysteine is very slow, making it inconvenient if the medium is needed immediately or in large quantity. The time required to reduce culture medium containing resazurin (an indicator of reducing conditions) was dramatically shortened when the medium, after being injected with the reducing agent cysteine, was irradiated with incandescent light from a halogen lamp. Light intensity had an effect upon reduction time: tubes kept in the dark took more than 12 h to achieve the desired degree of anaerobiosis (measured spectrophotometrically by the bleaching of the indicator, resazurin)...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Anaerobiosis; Culture medium; Cysteine; Light; Resazurin.
Ano: 2003
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1517-83822003000100006

Development of the nodulated soybean plant after flooding of the root system with different sources of nitrogen
Provedor de dados: 61
Autores: Thomas,André Luís; Sodek,Ladaslav.
Flooding leads to hypoxia, a stress to which symbiotic N2 fixation is especially sensitive. The response of fully nodulated soybean plants to a 21-day period of flooding was studied by measurements of growth parameters and xylem transport of organic nitrogenous components to the shoot, in the presence and absence of NO3- and NH4+ in the medium. Flooding was found to seriously impair N2 fixation, irrespective of the N source, as indicated by strongly reduced xylem ureide levels. In the absence of a source of N, growth was strongly reduced during flooding while accumulation of N in the shoot was virtually abolished. Flooding in the presence of 5 mM NO3- or NH4+ led to the accumulation of total N in the shoot but only NO3- promoted increases in total dry...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Glycine max; Anaerobiosis; Oxygen deficiency.
Ano: 2005
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1677-04202005000300003