Involvement of Asada-Halliwell Pathway During Phytoremediation of Chromium (VI) in Brassica juncea L. Plants.

Brassica juncea (Indian mustard) L. plants were exposed to different concentrations (0.0, 0.1, 0.3 and 0.5 mM) of Chromium (Cr) and harvested after 30 and 60 days of sowing for the analysis of growth parameters, metal uptake and oxidative stress markers. Significant accumulation of Cr (VI) by B. juncea L. plants resulted in the reduced growth and modulations in the pool of various biochemical stress markers. The toxic effects of Cr (VI) on growth and other stress markers (protein content, lipid peroxidation and antioxidative enzymes viz.SOD, CAT, POD, APOX, GR, DHAR and MDHAR) in B. juncea L. were observed to be concentration and time dependent. Effect of Cr (VI) on biochemical parameters was differential and their maximum activities of SOD, POD, APX, GR, DHAR and lipid peroxidation were recorded at 0.5 mM concentration in 30 days old plants. Whereas, trend in the activities of most of the stress markers was reversed in 60 days old plants. The results obtained from the study suggested that Cr (VI) stress inhibited growth of B. juncea L. plants is directly interrelated with its accumulation and resulted in the modulation in activities of various stress markers.