Some Biochemical Changes in the Lichen Evernia prunastri Exposed to Atmospheric Pollutants

Lichens have played an important role in air pollution studies as a bioindicator. The lichen Evernia prunastri was transplanted from a relatively unpolluted site in Serbia to six more polluted sites for a period of six months. The total proline contents, peroxidase activity, and content of secondary metabolites were determined before and after transplantation. Our findings show that relative high concentration of sulfur dioxide and other pollutants in the habitat of the above lichen cause oxidative stress, which promoted an increase in proline contents and changes peroxidase activity of thalli. The accumulation of proline was increased several times for lichen species. Atmospheric pollution caused a decrease in the activity of peroxidase in this lichen. HPLC analysis showed that the quantity of secondary metabolites was increased in the samples after transplantation to more polluted sites. Our results show that secondary metabolites might have an important role in the protection against atmospheric pollutants.