The effects of UV exposure on the antioxidant enzyme systems of anemones

Abstract

Superoxide dismutase (SOD), catalase (CAT) and glutathione peroxidase (GSH-Px) which are housekeeping enzymes protect cells from the harmful side effects of reactive oxygen species (ROS). Anemonia sulcata var. smaragdina and Anemonia rustica are widely distributed along the Turkish coastlines of the Aegean Sea. Recent studies have shown that environmental stresses such as elevated temperature, ultraviolet light, pathogen infection and decreased salinity might cause wellknown bleaching effects in Anemonia species. The effect of UV-light on antioxidant enzyme activities such as SOD, CAT, GSH-Px, protein levels and secondary pigments were determined in A. sulcata var. smaragdina and A. rustica. SOD, CAT, GSH-Px activities, protein levels and secondary pigments of these morphotypes were observed in both tentacles and columns separately. According to studies on bleaching, elevated UV radiation may cause the bleaching event in anemones as a stress factor. However, in the present study no bleaching event was observed in anemone samples even after they were subjected to 5 hours of UV-exposure intervals. Moreover, UV exposure did not change antioxidant systems remarkably. However, more investigations are still needed to obtain the complete picture of the effects of UV-light on the cellular pathways of cnidarian-algal symbiosis.