Determination of antioxidant capacities of some flavones and investigation of their inhibition effects on human carbonic anhydrase I and II isoenzymes, acetylcholinesterase, butyrylecholinesterase and lactoperoxidase enzymes

Within the scope of the thesis study, kinetic studies of 7-hydroxyflavone, 5-hydroxyflavone, 6-hydroxyflavone, 4'-5-dihydroxyflavone, 5,7-dihydroxyflavone on the human erythrocyte I and II isoenzymes (hCA I ve II), acetylcholinesterase, butyrylcholinesterase and lactoperoxidase enzymes were performed. For this purpose, inhibition effects of flavones on each enzyme were investigated by using the methods given in literature. IC50 and Ki values for each flavone against enzymes were calculated separately. In the second step of our study, in order to determine the antiradical and antioxidant activities of these flavones, Fe3+ (ferric ion) -Fe2+(ferrous ion) reducing activity, FRAP reducing activity, cupric ions (Cu2+) reducing activity, DPPH free radical scavenging method, ABTS radical scavenging method, DMPD∙+ radical scavenging and superoxide anion radical (O2·-) scavenging methods, ferrous ion (Fe2+) chelating activities using ferrozin reagents method are used.and in the last step, total antioxidant determination method was used according to ferric thiocyanate method. BHA, α-Tocopherol, Trolox, BHT were used as standard antioxidants during the studies and related comparisons were made. As a conclussion, it was observed that the flavones had similar activities to the Trolox.