ACCUMULATION OF HEAVY METALS AND ANTIOXIDANT RESPONSES IN AQUATIC PLANT TRAPA NATANS L. IN A FRESHWATER LAKE (THE SKADAR LAKE MONTENEGRO)

Due to their capacity to accumulate various pollutants into their tissue, macrophytes play important role in biomonitoring studies and assessments of lakes contamination by ecotoxic metals. The aim of this study was to assess content of several metals (Cu, Zn, Mn, Fe and Co) in sediment and plant organs (leaf, stem and root) of the species Trapa natans L. In addition, antioxidant status of Trapa natans L. was determined, with the purpose to evaluate if enzymes catalase (CAT) and guaiacol-peroxidase (GPX) can be used as biochemical indicators of the level of pollution of aquatic environment by heavy metals. Plant and sediment samples were taken from nine locations in the freshwater Skadar Lake, Montenegro. Contents of metals in the organs of Trapa natans L. varied in the ranges (in mg kg(-1)) 1.8-5.0 for Cu, 5-40 for Zn, 50-881 for Mn, 123-6808 for Fe and 0.10-2.28 for Co and were the highest for all metals in the root. Activity of CAT, (89282 U/g/w) was higher in leaf, while activity of GPX (1.9-10.7 U/g/w) was mostly higher in root of the plant. A statistically significant positive correlation was found between Zn content in the root of the species Trapa natans L. and activity of CAT.

Automated summary

The study assessed metal content in sediment and plant organs of Trapa natans L. and evaluated CAT and GPX as indicators of pollution in aquatic environments by heavy metals. Variations in metal content were observed in different organs, with the highest levels found in the root. CAT activity was higher in leaves, while GPX activity was higher in the root. A positive correlation was found between root zinc content and CAT activity.