Dişbudak(fraxinus excelsior-fraxinus americana) ağacının yapraklarındaki toplam fenolik bileşikler ve antioksidan kapasitesinin tayini

In this work, total amounts of the phenolic matter, total antioxidant capacities and radical scavenging capacity were determined in Fraxinus Excelsior and Fraxinus Americana leaves growing in the Western Anatolia and Mediterranean regions and belonging to the family of Oleaceae and the economic potential of these species for our country was evaluated. Both the extraction and infusion processes were applied to the samples after the leaves of Fraxinus Excelsior and Fraxinus Americana were dried and powdered. Total amounts of the phenolic matter, total antioxidant capacities and radical scavenging capacity of the leaves extracts were determined spectrophotometrically by Folin-Ciocalteu, CUPRAC (Cupric ion reducing antioxidant capacity) and DPPH (DPPH (2,2-diphenyl-1-picrylhydrazyl) radical scavenging capacity) methods, respectively. Total amounts of the phenolic matter in the methanol:water (70:30, v/v) extracts of the leaves were determined as 110.92±4.75 mg GAE/ g sample and 70.21±3.64 mg GAE/ g sample in Fraxinus Americana and Fraxinus Excelsior, respectively. Moreover, 45.06±5.16 mg GAE/ g sample for Americana Fraxinus and 46.45±4.49 mg GAE/ g sample for Fraxinus Excelsior were found in the infusion extracts of the leaves. DPPH methods in the methanol:water (70:30, v/v) extracts of the leaves were calculated as 2.21±0.01 mg TE/ g sample and 2.19±0.04 mg TE/ g sample via DPPH method in Fraxinus Americana and Fraxinus Excelsior, respectively. In addition, 2.08±0.07 mg TE/ g sample for Americana Fraxinus and 2.08±0.07 mg TE/ g sample for Fraxinus Excelsior were found in the infusion extracts of the leaves. CUPRAC methods in the methanol:water (70:30, v/v) extracts of the leaves were determined as 238.38±6.74 mg TE/ g sample and 138.45±5.07 mg TE/ g sample with CUPRAC method in Fraxinus Americana and Fraxinus Excelsior, respectively. Furthermore, 76.74±3.31 mg TE/ g sample for Americana Fraxinus and 91.42±2.66 mg TE/ g sample for Fraxinus Excelsior were calculated in the infusion extracts of the leaves. Oleuropein, the major component of the Oleaceae family, was found as 55192.12 ± 3863.45 µg/g in the methanol:water (70:30, v/v) extract, 29442.74 ± 2060.99 µg/g in the infusion extract of Fraxinus Excelsior leaves and 27085.27 ± 1895.97 µg/g g in the methanol:water (70:30, v/v) extract, 17298.65 ± 1210.91 µg/g in the infusion extract of Fraxinus Americana leaves. Tyrosol amount of the extracts of Fraxinus Excelsior leaves were found as 153.37 ±.12.27 µg/g and 405.89 ±27.35 µg/g in the methanol:water (70:30, v/v) extract and the infusion extract, respectively. In addition, 119.49 ±.16.30 µg/g tyrosol for the methanol:water (70:30, v/v) extract and 362.79 ±25.39 µg/g tyrosol for the infusion extract of Fraxinus Americana were determined quantitatively. Hydroxytyrosol was determined as 118.40 ±15.25 µg/g in the methanol:water (70:30, v/v) extract, 392.11 ±26.15 µg/g in the infusion extract of Fraxinus Excelsior leaves and 161.45 ±19.37 µg/g in the methanol:water (70:30, v/v) extract, 496.33±27.35 µg/g in the infusion extract of Fraxinus Americana leaves. Chlorogenic acid, hesperidin and verbascoside which are abundant in Fraxinus Excelsior leaves were found as 1764.67 ± 24.63 µg/g, 23691.29 ± 1147.36 µg/g and 2809.06 ± 78.63 µg/g in the methanol:water (70:30, v/v) extracts , respectively. Furthermore, hyperoside, hesperidin and verbascoside were determined as 329.28 ± 25.04 µg/g, 7091.47 ± 305.54 µg/g and 6850.13 ± 968.07 µg/g in the infusion extracts of Fraxinus Excelsior leaves. Luteolin 7-glucoside, hesperidin and verbascoside amounts were found as 983.58 ± 30.38 µg/g, 14369.23 ± 238.02 µg/g and 18585.06 ± 265.43 µg/g in the methanol:water (70:30, v/v) extracts of Fraxinus Americana leaves. In addition, chlorogenic acid, hesperidin and verbascoside were determined as 963.49 ± 51.64 µg/g, 11086.24 ± 1131.70 µg/g and 846.60 ± 133.88 µg/g in the infusion extracts of Fraxinus Americana leaves. Keywords: Fraxinus Excelsior, Fraxinus Americana, Oleaceae, Total amounts of the phenolic matter, CUPRAC, DPPH, Oleuropein