THE INFLUENCE OF GLUTATHIONE ON PHYSIOLOGICAL EFFECTS OF LEAD AND ITS ACCUMULATION IN MOSS SPHAGNUM SQUARROSUM

摘要

An attempt has been made to study the physiological and biochemical responses and to evaluate the bioaccumulation potential of moss Sphagnum to environmental lead. Supply of 0.1 to 100 mM lead acetate caused a loss in chlorophyll and nitrogen content of moss and in nitrate reductase activity in the moss, although the peroxidase activity was increased. Partial recovery in the above parameters was recorded upon simultaneous treatment with glutathione. Results also indicate that treatment with glutathione increased the bioaccumulation potential by lowering the lead toxicity, which could be the result of induction of metal binding capabilities of cells as the heavy metal also induced the synthesis of phytochelatins. The moss accumulated a significant amounts of Pb under both experimental and field conditions. The heavy metal accumulated by moss was positively correlated to the soil metal content. The experiments demonstrate that Sphagnum is able to accumulate and tolerate higher amounts of Pb and therefore, it can be used as a bioindicator and phytoremediator of lead contaminated environment.