THE TOXICOLOGICAL EFFECTS OF THE ORGANOCHLORINE PESTICIDES AND METALS ON THE ACTIVITY OF CARBONIC ANHYDRASE FROM SIIRT/BOTAN FISH (CAPOETA CAPOETA) IN THE TIGRIS BASIN

Abstract

After the application of pesticides to agricultural areas, they reach the rivers by transporting with rain water and irrigation water, They give harms to the ecosystem there, fish and other creatures. Metals also play vital roles in enzyme activities and other metabolic events due to their bioaccumulative structures. Fish, as a link of food chain, accumulate persistent organic pollutants in their organs and tissues as a result of the biomagnification process. Moreover, environmental toxins first encounter the gill tissue in fish. In present study, the carbonic anhydrase enzyme was purified 369.8 folds with 70.6% yield by Sepharose-4B-L-tyrosine-sulfanilamide affinity column from Siirt/Botan fish (Capoeta capoeta) gill tissue. The specific activity was determined as 6.175 EU/mg protein. The molecular weight was found to be about 31.8 kDa by SDS-PAGE. Inhibitory effects of organochlorine pesticides (beta-Endosulfan and 2,4'-DDT) and metal ions (Al3+, Cu2+, Ba2+, Fe2+ and Se2+) were examined on the purified CA enzyme. Inhibition graphics were drawn in order to find the IC50 values of metals and organochlorine pesticides. In vitro inhibitory effect of metals was found as Fe2+ >Al3+> Ba2+> Se2+> Cu2+. Very low IC50 values were obtained such as 0.062 and 0.051 mM in the presence of the 2,4'-DDT and beta-Endosul fan.