Investigation of biochemical responses of Bacopa monnieri L. upon exposure to arsenate. Issue 8 (7th June 2011)

• Record Type: Journal Article
• Authors: Mishra, Seema; Srivastava, Sudhakar; Dwivedi, Sanjay; Tripathi, Rudra Deo
• Is Part Of: Environmental toxicology. Volume 28:Issue 8(2013:Aug.)
• Page Start: 419
• Page End: 430
• Publication Date: 2011-06-07
• Subjects: Water quality bioassay -- Periodicals; Water -- Pollution -- Toxicology -- Periodicals; Microbiological assay -- Periodicals; Toxicity testing -- Periodicals; Environmental toxicology -- Periodicals; Environmental Pollution -- Periodicals; Environmental Pollutants -- Periodicals; Environmental Monitoring -- Periodicals; Écotoxicologie -- Périodiques; Pollution -- Périodiques; 615.902
• DOI: 10.1002/tox.20733
• Languages: English
• ISSNs: 1520-4081

Abstract

<abstract abstract-type="main"> <title> <x xml:space="preserve">Abstract</x> </title> <p>Widespread contamination of arsenic (As) is recognized as a global problem due to its well‐known accumulation by edible and medicinal plants and associated health risks for the humans. In this study, phytotoxicity imposed upon exposure to arsenate [As(V); 0–250 μM for 1–7 days] and ensuing biochemical responses were investigated in a medicinal herb <italic>Bacopa monnieri</italic> L. vis‐à‐vis As accumulation. Plants accumulated substantial amount of As (total 768 μg g<sup>−1</sup> dw at 250 μM As(V) after 7 days) with the maximum As retention being in roots (60%) followed by stem (23%) and leaves (17%). The level of cysteine and total nonprotein thiols (NP‐SH) increased significantly at all exposure concentrations and durations. Besides, the level of metalloid binding ligands viz., glutathione (GSH) and phytochelatins (PCs) increased significantly at the studied concentrations [50 and 250 μM As(V)] in both roots and leaves. The activities of various enzymes viz., arsenate reductase (AR), glutathione reductase (GR), superoxide dismutase (SOD), guaiacol peroxidase (GPX), ascorbate peroxidase (APX), and catalase (CAT) showed differential but coordinated stimulation in leaves and roots to help plants combat As toxicity up to moderate exposure concentrations (50 μM). However, beyond 50 μM, biomass production was found to decrease along with photosynthetic pigments and total soluble proteins, whereas lipid peroxidation increased. In conclusion, As accumulation potential of <italic>Bacopa</italic> may warrant its use as a phytoremediator but if <italic>Bacopa</italic> growing in contaminated areas is consumed by humans, it may prove to be toxic for health. © 2011 Wiley Periodicals, Inc. Environ Toxicol 28: 419–430, 2013.</p> </abstract>