Biological activities of some lichen metabolites

In this thesis, in vitro inhibitory effects of usnic acid, vulpinic acid and psoromic acid which are secondary metabolite of the some lichens were investigated on the human erythrocyte hCA-I and hCA-II, acetylcholinesterase and butyrylcholinesterase enzymes. SDS-PAGE was performed to determine the purity of hCA-I and hCA-II isoenzymes obtained by Sepharose-4B-L-tyrosine affinity column chromatography from human erythrocytes and single band was observed. The inhibitory effects of the compounds on hCA-I and hCA-II isoenzymes, the acetylcholineesterase and butyrylcholineesterase enzymes were investigated by the esterase activity method and IC50 and Ki values were calculated for each substance. The IC50 and Ki values of Usnic acid were calculated for hCA-I, hCA-II, acetylcholinesterase and butyrylcholinesterase respectively as 2.675, 2.133; 6.728, 5.900; 1.273, 0.239; 3.397, 1.425 nM; The IC50 and Ki values of Vulpinic acid were calculated for hCA-I, hCA-II, acetylcholinesterase and butyrylcholinesterase respectively as 2.566, 1.246; 7.000, 4.560; 0.958, 0.227; 3.766, 1.302 nM; The IC50 and Ki values of Psoromic acid were calculated for hCA-I, hCA-II, acetylcholinesterase and butyrylcholinesterase respectively as 4.985, 2.833; 11.550, 14.230; 0.742, 0.122; 3.315, 2.079 nM. In the study antioxidant and radical elimination capacities of usnic acid, vulpinic acid and psoromic acid were evaluated. For this purpose, the FRAP method, Fe3+-Fe2+ reduction capacity, cupric ions (Cu2+) reduction capacity by cuprac method, DPPH· removal, ABTS∙+ removal, DMPD∙+ removal and superoxide anion radical (O2∙-) removal activities and and ferrous ions (Fe2+) chelating activity by bipyridyl reactifie were measured by was studied. In the study standard antioxidants BHA, BHT, trolox and α-tocopherol were also used as reference substances.