DETERMINATION OF SUPEROXIDE DISMUTASE (SOD), CATALASE (CAT), REDUCED GLUTATHION (GSH), MALONDIALDEHYDE (MDA), DIPHENYL-PICRILHIDRAZIN (DPPH) and FLAVONOIDE (FLA) LEVELS IN MEDLAR (Mespilus germanica L.), MAHALEP (Prunus mahaleb L.) AND BITTER MELON (Momordica charantia L.)

Free radicals are reactive molecules that occur as a byproduct of oxygen metabolism and create toxic effects on cells free radicals are reactive molecules that occur as a byproduct of oxygen metabolism and create toxic effects on cells. Antioxidants, on the other hand, play an important role in the prevention and treatment of various diseases caused by oxidative stress by neutralizing or eliminating these free radicals. In this study, Medlar (Mespilus germanica L.), Mahalep (Prunus mahaleb L .) and Pomegranate of Might (Momordica charantia L .) some antioxidant activities of fruits were investigated. The activities of superoxide dismutase (SOD), catalase (CAT), reduced glutathione (GSH) and malondialdehyde (MDA) levels and DPPH radical quenching capacities, which play an important role in preventing oxidative stress caused by free radicals in cells, were measured. Additionally, the total flavonoid component contents of the extracts were measured in quercetin equivalents. In the study, SOD activity was determined as 3.29 U/ml for Medlar, 14.01 U/ml for Mahalep, and 1.09 U/ml for Bitter Melon. CAT activity was measured as 28.69 U/L in Medlar, 30.19 U/L in Mahalep, and 28.53 U/L in Bitter Melon, respectively. GSH levels were found to be 0.35 mmol/glutathione in Medlar, 4676.70 mmol/glutathione in Mahalep and 1336.20 mmol/glutathione in Bitter Melon. MDA levels, which are an indicator of lipid peroxidation, were calculated as 2.25 μmol/L in Medlar, 1.18 μmol/L in Mahalep and 2.28 μmol/L in Bitter Melon. DPPH radical quenching activity was studied at different concentrations (50-1000 μg/ml) and was found in the inhibition December of 85.28-88.71% in Medlar, 70.42-77.29% in Mahalep, 82.91-88.18% in Bitter Melon. The total amounts of flavonoids were determined as 18.61±2.56 μg in Medlar, 20.57±2.56 μg in Mahalep and 19.24±2.56 μg quercetin equivalent in Bitter Melon. The findings showed that Mahalep extract was superior to other species in SOD activities and GSH lives, while similar values were observed between species in CAT activity. In terms of DPPH radical quenching capacity, Bitter Melon and Medlar showed higher antioxidant activity than Mahalep. In terms of MDA levels, Mahalep was found to have a lower value against lipid peroxidation. In terms of total flavonoid content, Mahalep was found to have a slightly higher value compared to other species. These results were found to be high in terms of antioxidant activities of the fruit extracts studied.