Arsenic accumulation and tolerance in rootless macrophyte Najas indica are mediated through antioxidants, amino acids and phytochelatins.
Aquat Toxicol
; 157: 70-80, 2014 Dec.
Article
em En
| MEDLINE
| ID: mdl-25456221
ABSTRACT
Arsenic (As) accumulation and tolerance response of a submerged rootless macrophyte Najas indica were evaluated during arsenate (As(V); 10-250 µM) and arsenite (As(III); 1-50 µM) exposure. Higher As accumulation at As(III) exposure and more tolerance upon As(V) exposure resulted in more toxicity during As(III) stress than As(V), which was evident through measurement of growth parameters and oxidative stress related parameters viz., lipid peroxidation (MDA content), electrical conductivity (EC) and hydrogen peroxide (H2O2) levels. Antioxidant enzymes and various amino acids were more prominent during moderate exposure of As(V), suggesting their possible role in As tolerance and detoxification. Various non-enzymatic antioxidant metabolites viz., ascorbic acid (ASC), glutathione (GSH), non-protein thiols (NPTs) and phytochelatins (PCs) biosynthesis involving phytochelatin synthase (PCS) activity increased more significantly during As(III) stress. However, PCs content seems inadequate in response to As accumulation leading to lower PC-SHAs molar ratio and higher As phytotoxicity during As(III) stress. N. indica may prove useful plant species for phytoremediation purpose in moderately As contaminated water bodies due to high As accumulation and tolerance potential.
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Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Arsênio
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Alismatales
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Fitoquelatinas
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Aminoácidos
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Antioxidantes
Idioma:
En
Ano de publicação:
2014
Tipo de documento:
Article