Comparative analysis of antioxidant activity in leaves of different hosts infected by mistletoe (Viscum album L. subsp. album)

Studies were performed at different sites in the major city of Lodz (Poland), where mistletoe is particularly abundant. The occurrence of total antioxidant enzyme activities such as superoxide dismutase (SOD), guaiacol peroxidase (POD) and the protein and phenol contents in leaves from different hosts infected by European mistletoe (Viscum album L. subsp. album) were studied. Some elements may vary in samples from the same mistletoe species on different host trees and species. The most important are changes in the concentration of proteins, including enzyme and stress proteins, in the leaves of trees infected by mistletoe, may indirectly indicate an interaction between host and parasite. There were no important differences in the soluble phenolic content after infection. The change in POD after infection was not significant in comparison to control plants. The SOD activity was significantly higher in leaves from infected trees in comparison to control plants. The obtained data suggest that the increase in SOD and protein content depends mainly on the host taxa. Moreover, we suggest that the main increase in SOD activities in leaves is a consequence of the stress oxidation that caused infection and development of the parasite on the host plant. Chemical analyses of mistletoe from a large sample of host species provide evidence that this parasite may be extremely tolerant to air pollution