Consulta: subjectFacets:"Antioxidant system"
Registros recuperados: 7
Data/hora: 10/06/2024 14:07:25

Plant responses to stresses: role of ascorbate peroxidase in the antioxidant protection
Provedor de dados: Genetics and Molecular Biology
Autores: Caverzan,Andréia; Passaia,Gisele; Rosa,Silvia Barcellos; Ribeiro,Carolina Werner; Lazzarotto,Fernanda; Margis-Pinheiro,Márcia.
When plants are exposed to stressful environmental conditions, the production of Reactive Oxygen Species (ROS) increases and can cause significant damage to the cells. Antioxidant defenses, which can detoxify ROS, are present in plants. A major hydrogen peroxide detoxifying system in plant cells is the ascorbate-glutathione cycle, in which, ascorbate peroxidase (APX) enzymes play a key role catalyzing the conversion of H2O2 into H2O, using ascorbate as a specific electron donor. Different APX isoforms are present in distinct subcellular compartments, such as chloroplasts, mitochondria, peroxisome, and cytosol. The expression of APX genes is regulated in response to biotic and abiotic stresses as well as during plant development. The APX responses are...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Ascorbate peroxidase; Antioxidant system; Reactive oxygen species; Abiotic stress; Mutant plants.
Ano: 2012
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1415-47572012000600016

Oxidative stress caused by the use of preemergent herbicides in rice crops
Provedor de dados: Revista Ciência Agronômica (RCA)
Autores: Langaro,Ana Claudia; Agostinetto,Dirceu; Ruchel,Queli; Garcia,Jessica Rodrigues; Perboni,Lais Tessari.
ABSTRACT Among the methods of weed control, stands out chemical control. However, even selective, herbicides can trigger the production of reactive species of oxygen and cause oxidative stress. The aim of the study was to evaluate changes in photosynthetic parameters, oxidative damage, antioxidant enzyme activity and altered metabolism of rice plants after applying pre-emergent herbicides. The experiment was conducted in a greenhouse and herbicides used were oxadiazon, pendimethalin and oxyfluorfen, beyond the control without herbicide. There was a reduction of photosynthetic rate and efficiency of carboxylation, compared to the control, when applied herbicides oxyfluorfen and pendimethalin. The major lipid peroxidation and proline accumulation was...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Antioxidant system; Chemical control; Reactive oxygen species; Selectivity.
Ano: 2017
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1806-66902017000200358

Physiological responses of soybean (Glycine max (L.) Merrill) cultivars to copper excess
Provedor de dados: Anais da Academia Brasileira de Ciências
Autores: SCHWALBERT,RAISSA; SILVA,LINCON O.S.; SCHWALBERT,RAI A.; TAROUCO,CAMILA P.; FERNANDES,GILLIAN S.; MARQUES,ANDERSON C.R.; COSTA,CAMILA C.; HAMMERSCHMITT,RODRIGO K.; BRUNETTO,GUSTAVO; NICOLOSO,FERNANDO T.
Abstract Abstract: Successive applications of copper fungicides on vines have resulted in increased copper content in vineyard soils over the years. This high copper content has affected the growth of young vines in eradicated vineyards. Thus, the cultivation of annual species for a few years is an alternative to copper phytostabilization, because it would be a good way to decrease copper availability to plants. The aim of this study was to evaluate the physiological responses of different soybean cultivars to copper concentration increase. Four different soybean cultivars were grown under three copper concentrations: 0.5, 20 and 40 μM in nutrient solution. The main outcomes of this study were: i) Cultivar M 6410 IPRO recorded the highest photosynthetic...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Antioxidant system; Cash crops; Heavy metal phytostabilization; Photosynthesis.
Ano: 2019
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0001-37652019000700618

Oxidative stress and fish immune system: phagocytosis and leukocyte respiratory burst activity
Provedor de dados: Anais da Academia Brasileira de Ciências
Autores: BILLER,JAQUELINE D.; TAKAHASHI,LEONARDO S.
Abstract Molecular oxygen is a necessary compound for all aerobic organisms, although oxygen is a potent oxidant, which can cause oxidative stress (OS). OS occurs when there is an imbalance between the production of oxidant and antioxidants components, are result of normal cell metabolism, and many of these compounds play a fundamental role in several metabolic pathways. The organism produces several reactive oxygen species (ROS), but they are balanced by an antioxidant defense system that maintains the levels of these oxidizing compounds at an acceptable level. Many of these components are essential in the organism defense and their byproducts are considered potent bactericides that actively act in the destruction of invading pathogens. Fish immune system...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Reactive oxygen species; Innate immunity; Antioxidant system; Free radical.
Ano: 2018
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0001-37652018000703403

Mechanisms involved in reproductive damage caused by gossypol in rats and protective effects of vitamin E
Provedor de dados: Biological Research
Autores: Santana,Andréia T; Guelfi,Marieli; Medeiros,Hyllana C D; Tavares,Marco A; Bizerra,Paulo F V; Mingatto,Fábio E.
BACKGROUND: Gossypol is a chemical present in the seeds of cotton plants (Gossypium sp.) that reduces fertility in farm animals. Vitamin E is an antioxidant and may help to protect cells and tissues against the deleterious effects of free radicals. The aim of this study was to evaluate the mechanisms of reproductive toxicity of gossypol in rats and the protective effects of vitamin E. Forty Wistar rats were used, divided into four experimental groups (n = 10): DMSO/ saline + corn oil; DMSO/saline + vitamin E; gossypol + corn oil; and gossypol + vitamin E. RESULTS: Fertility was significantly reduced in male rats treated with gossypol in that a significant decrease in epididy-mal sperm count was observed (P &lt; 0.05) and the number of offspring was...
Tipo: Journal article
Palavras-chave: Gossypol; Fertility; Oxidative stress; Bioenergetics; Antioxidant system; Vitamin E.
Ano: 2015
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0716-97602015000100043

Oxidative processes during 'Golden' papaya fruit ripening
Provedor de dados: Brazilian Journal of Plant Physiology
Autores: Resende,Evellyn Couto Oliveira; Martins,Paula Fabiane; Azevedo,Ricardo Antunes de; Jacomino,Angelo Pedro; Bron,Ilana Urbano.
'Golden' papayas at maturity stage 1 (15% yellow skin) were chosen to study selected oxidative processes, the activity of antioxidant enzymes and lipid peroxidation in storage at 22°C, during the ripening of the fruit. An increase in ethylene production was observed on the second day of storage and it was followed by an increase in respiration. An increased activity of catalase, glutathione reductase and ascorbate peroxidase was observed concurrently or soon after this increase in ethylene production and respiration. The increased activity of these enzymes near the peaks of ethylene production and respiration is related to the production of oxidants accompanying the onset of ripening. On the fourth day of storage, there was an increased lipid peroxidation...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Carica papaya; Antioxidant system; Climacteric; Ethylene; Lipid peroxidation.
Ano: 2012
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1677-04202012000200002

CROSS-TOLERANCE MECHANISM INDUCTION IN MELON SEEDS BY PRIMING PRIOR DRYING
Provedor de dados: Ciência e Agrotecnologia
Autores: Lira,Jean Marcel Sousa; Lara,Túlio Silva; Rodrigues,Amanda Cristiane; Dousseau,Sara; Magalhães,Marcelo Murad; Alvarenga,Amauri Alves de.
The loss of benefits after re-drying is one of the drawbacks of the seed priming technique. Different types of stresses have been used before re-drying to preserve the priming benefits. This process may be seen as promoting cross tolerance to increase the defense mechanisms that prevent loss of viability in seeds primed after drying. We tested the effect of some stresses to induce cross-tolerance and different drying conditions with the aim of maintaining priming benefits in melon seeds. The seeds were primed in an aerated KNO3 solution (0.35M), -1.7MPa, 25 °C, in the dark for six days. The primed seeds were then submitted to slow drying, fast drying, cold shock + slow drying, cold shock + fast drying, heat shock + slow drying, heat shock + fast drying,...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: PEG; Priming; Dry seeds; Antioxidant system.
Ano: 2015
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1413-70542015000200131