Changes in nitrate reductase activity and oxidative stress response in the moss Polytrichum commune subjected to chromium, copper and zinc phytotoxicity
Document title: Changes in nitrate reductase activity and oxidative stress response in the moss Polytrichum commune subjected to chromium, copper and zinc phytotoxicity
Journal: Brazilian journal of plant physiology
Database: PERIÓDICA
System number: 000276176
ISSN: 1677-0420
Authors: 1
2
Institutions: 1Okayama University, Research Institute for Bioresources, Okayama. Japón
2Assam (Central) University, School of Life Sciences, Silchar, Assam. India
Year:
Season: Abr-Jun
Volumen: 17
Number: 2
Pages: 191-197
Country: Brasil
Language: Inglés
Document type: Artículo
Approach: Experimental, analítico
English abstract The main aim of this paper was to investigate the effect of chromium (Cr), copper (Cu) and zinc (Zn) on nitrate reductase (NR) activity and oxidative stress responses in the moss Polytrichum commune. Cr, Cu and Zn resulted in the inhibition of NR activity. A decline in total chlorophyll content was observed after 24 and 48 h of metal treatment. Accumulation of the metals showed a dose and time dependent increase. High accumulation of Cu, Cr and Zn were seen in moss shoots after 24 and 48 h of treatment. Treatment of Cr, Cu and Zn for 24 or 48 h resulted in the increase of malondialdehyde (MDA) content in moss shoots. The highest increase was observed in shoots under Cu treatment followed by Cr and Zn. The MDA content was significantly higher after 48h. Antioxidant enzymes viz., catalase (CAT), guaiacol peroxidase (GPx), glutathione reductase (GR) and superoxide dismutase (SOD) were affected by elevated concentrations of the three metals. Increase in the activity of CAT, GR and SOD was seen after 24 and 48 h of treatment. GPx activity declined under Cr treatment. However, under Cu and Zn, an increase in GPx was seen after 24 h and 48 h of treatment. For Zn, the antioxidant efficiency was less affected as compared to Cr and Cu. The response of Polytrichum commune to toxic concentrations of Cr, Cu and Zn appears to induce oxidative damage as observed by the increase in MDA content and antioxidant metabolism
Portuguese abstract O principal objetivo deste trabalho foi investigar o efeito do cromo (Cr), cobre (Cu) e zinco (Zn) sobre a atividade da redutase do nitrato (RN) e respostas ao estresse oxidativo no musgo Polytrichum commune. Cr, Cu e Zn causaram a inibição da atividade da RN. Uma diminuição na clorofila total foi observada após 24 e 48 h dos tratamentos com os metais. O acúmulo de metais mostrou ser dependente do aumento da dose e tempo. Observou-se grande acúmulo de Cu, Cr e Zn nos brotos depois de 24 e 48 h dos tratamentos. Aqueles com Cr, Cu e Zn por 24 ou 48 h resultou no aumento do conteúdo de malondialdeído (MDA) nos brotos. Verificou o maior aumento nos brotos tratados com Cu, seguidos por Cr e Zn. O conteúdo de MDA foi significamente maior após 48 h. Enzimas antioxidantes, como catalase (CAT), peroxidase do guaiacol (GPx), redutase da glutationa (GR) e dismutase do superóxido (SOD) foram afetadas por elevadas concentrações dos três metais. Aumentos nas atividades de CAT, GR e SOD foram observados após 24 e 48 h dos tratamentos. A atividade de GPx diminuiu com o tratamento de Cr, porém, com Cu e Zn, observou-se aumento de GPx após 24 h e 48 h do tratamento. Para o Zn, a eficiência antioxidante foi menos afetada quando comparada ao Cr e Cu. A resposta de Polytrichum commune a concentrações tóxicas de Cr, Cu e Zn parece ser induzida pelo dano oxidativo quando observado através do aumento do conteúdo de MDA e metabolismo antioxidante
Disciplines: Biología,
Química
Keyword: Fisiología vegetal,
Bioquímica,
Estrés oxidativo,
Cobre,
Cromo,
Malondialdehído,
Polytrichum commune,
Zinc,
Antioxidantes,
Nitrato reductasa
Keyword: Biology,
Chemistry,
Plant physiology,
Biochemistry,
Chromium,
Copper,
Malondialdehyde,
Nitrate reductase,
Oxidative stress,
Polytrichum commune,
Zinc,
Antioxidants
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