Arsenic pollution is a growing menace in major parts of West Bengal, India and Bangladesh. Arsenic phytoremediation abilities of two common plants Pteris vittata and Eichhornia crassipes growing abundantly under natural tropical conditions of India were biochemically analyzed. Reactive oxygen species, taking total peroxide and malondialdehyde contents as the parameters, indicate the extent of arsenic induced oxidative stress, while the activities of the scavenging enzymes catalase, peroxidase and superoxide dismutase indicate the comparative effectiveness of the two plants in arsenic detoxification. Total peroxide and MDA contents were significantly higher in all samples of Eichhornia as compared to Pteris throughout the experimental period while the three scavenging enzymes viz. catalase, peroxidase and superoxide dismutase exhibited higher activities in Pteris with increasing arsenic concentration while Eichhornia showed a reverse trend. The comparative study reveals that Pteris vittata is the more efficient plant in combating and tolerating arsenic stress, as revealed by the results obtained of biochemical constituents and enzymatic profile. Of the two selected plant species,Pteris is found to be more effective in arsenic removal can serve as a cheap and easily available green source for arsenic detoxification.
Key words: Arsenic toxicity, oxidative stress, reactive oxygen species, plant antioxidant defense, stress amelioration