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Öğe Antioxidant Activity and Total Phenolic Contents of Different Alfalfa (Medicago sativa L.) Varieties Grown in Turkey(Centenary University, 2021) Orak, Hakime Hülya; Karamac, Magdalena; Orak, Adnan; Tenikecier, Hazım Serkan; Amarowicz, RyszardFifteen alfalfa varieties cultivated in Turkey were researched to compare the antioxidant potential of their seeds and find differences between the varieties. The total phenolic (TP) content, DPPH•, and ABTS•+ scavenging activities, and ferric-reducing antioxidant power (FRAP) of alfalfa seed methanol extracts were determined. TP contents of extracts were found between 37.03 and 54.04 mg GAE/g. ABTS assay results ranged between 0.100 and 0.158 mmol Trolox/g extract, and FRAP changed from 389.90 to 791.02 µmol Fe2+/g extract. The results demonstrated that the differences between the alfalfa varieties were significant (p < 0.01) in terms of analyzed characters. © 2021, Centenary University. All rights reserved.Öğe ANTIOXIDANT ACTIVITY OF PHENOLIC COMPOUNDS OF RED BEAN (Phaseolus vulgaris L.)(Scibulcom Ltd, 2015) Orak, Hakime Hülya; Karamac, Magdalena; Amarowicz, RyszardAntioxidant potential of seeds of commonly cultivated two read bean cultivars, namely Onceler and Mecidiye, was evaluated. The crude extracts of phenolic compounds were obtained using by 80% (v/v) methanol and acetone. The antioxidant potential of the seeds was tested using TEAC, FRAP, and DPPH method. The presence of phenolic acids and flavonoids was confirmed using HPLC method. The results of the present study showed red kidney bean, cultivated in Turkey, to be potentially valuable legume crops with high antioxidant potential.Öğe Antioxidant activity of phenolic compounds of red bean (Phaseolus vulgaris L.)(Scibulcom Ltd., 2015) Orak, Hakime Hülya; Karamac, Magdalena; Amarowicz, RyszardAntioxidant potential of seeds of commonly cultivated two read bean cultivars, namely Onceler and Mecidiye, was evaluated. The crude extracts of phenolic compounds were obtained using by 80% (v/v) methanol and acetone. The antioxidant potential of the seeds was tested using TEAC, FRAP, and DPPH method. The presence of phenolic acids and flavonoids was confirmed using HPLC method. The results of the present study showed red kidney bean, cultivated in Turkey, to be potentially valuable legume crops with high antioxidant potential. © 2015, Scibulcom Ltd. All rights reserved.Öğe Antioxidant Potential and Phenolic Compounds of Some Widely Consumed Turkish White Bean (Phaseolus vulgaris L.) Varieties(De Gruyter Open Ltd, 2016) Orak, Hakime Hülya; Karamac, Magdalena; Orak, Adnan; Amarowicz, RyszardThe antioxidant potential and phenolic compounds content were investigated in ten white bean varieties widely consumed in Turkey. Total phenolic contents of seeds varied between 0.33 and 0.63 mg GAE/g. The Trolox Equivalent Antioxidant Capacity (TEAC) determined by the ABTS assay and the Ferric-Reducing Antioxidant Power (FRAP) of bean varieties ranged from 3.50 to 5.17 mu mol Trolox/g seed and from 7.99 to 11.20 mu mol Fe2+-/g seed, respectively. Strong correlations were found between total phenolic content and FRAP (r=0.850) and between TEAC and FRAP (r=0.734). The antioxidant activity was investigated in a beta-carotene-linoleic acid model system, as well. Differences in the inhibition of emulsion oxidation by extracts of white bean varieties were slight. The RP-HPLC fingerprint analysis of extracts showed the presence of five dominant phenolic compounds which were described as ferulic or caffeic acids derivatives. Four of them significantly contributed to reducing power and antiradical activity against ABTS(center dot+) of extracts.Öğe Genotype-Related Differences in the Phenolic Compound Profile and Antioxidant Activity of Extracts from Olive (Olea europaea L.) Leaves(Mdpi, 2019) Orak, Hakime Hülya; Karamac, Magdalena; Amarowicz, Ryszard; Orak, Adnan; Penkacik, KamilaThe phenolic compound contents and antioxidant activities of the leaf extracts of nine olive genotypes were determined, and the obtained data were analysed using chemometric techniques. In the crude extracts, 12 compounds belonging to the secoiridoids, phenylethanoids, and flavonoids were identified. Oleuropein was the primary component for all genotypes, exhibiting a content of 21.0 to 98.0 mg/g extract. Hydroxytyrosol, verbascoside, luteolin 7-O-glucoside, and luteolin 4-O-glucoside were also present in noticeable quantities. Genotypes differed to the greatest extent in the content of verbascoside (0.45-21.07 mg/g extract). The content of hydroxytyrosol ranged from 1.33 to 4.03 mg/g extract, and the aforementioned luteolin glucosides were present at 1.58-8.67 mg/g extract. The total phenolic content (TPC), DPPH center dot and ABTS(center dot+) scavenging activities, ferric reducing antioxidant power (FRAP), and ability to inhibit the oxidation of -carotene-linoleic acid emulsion also varied significantly among genotypes. A hierarchical cluster analysis enabled the division of genotypes into three clusters with similarity above 60% in each group. GGE biplot analysis showed olive genotypes variability with respect to phenolic compound contents and antioxidant activities. Significant correlations among TPC, FRAP, the values of both radical scavenging assays, and the content of oleuropein were found. The contents of 7-O-glucoside and 4-O-glucoside correlated with TPC, TEAC, FRAP, and the results of the emulsion oxidation assay.Öğe Phenolic contents and antioxidant capacities of wild and cultivated white lupin (Lupinus albus L.) seeds(Elsevier Sci Ltd, 2018) Karamac, Magdalena; Orak, Hakime Hülya; Amarowicz, Ryszard; Orak, Adnan; Piekoszewski, WojciechThe aim of this study was to compare the antioxidant capacities and phenolic compound profiles of wild and cultivated Lupinus albus L. seeds. The total phenolic content (TPC), radical scavenging activity, ferric-reducing antioxidant power (FRAP) and antioxidant activity in an beta-carotene-linoleic acid emulsion were determined. Liquid chromatography-mass spectrometry was used to identify phenolics. The TPC of lupin seeds ranged from 4.36 to 7.24 mg gallic acid equivalent/g dry matter (d.m.). The dominant phenolics of all genotypes were two p-coumaric acid derivatives (0.74-1.61 and 0.66-1.63 mg/g d.m.) and apigenin-6,8-di-C-glucoside (1.13-1.31 mg/g d.m.). The results of antioxidant assays of wild lupin extracts were similar to or lower than those of the cultivated variety. FRAP and ABTS(center dot+) scavenging activity were correlated with the contents of the more polar p-coumaric acid derivative and apigenin-6,8-di-C-glucoside. Generally, significant differences between cultivated and wild L. albus seeds were not found in antioxidant capacities and phenolic compound contents.Öğe Variations of genotypes of Vicia species as influenced by seed phenolic compounds and antioxidant activity(Lithuanian Research Centre Agriculture & Forestry, 2022) Orak, Hakime Hülya; Karamac, Magdalena; Amarowicz, Ryszard; Orak, Adnan; Janiak, Michal Adam; Tenikecier, Hazim SerkanThe phenolic compounds and antioxidant activity of different Vicia species, which are cultivated in different areas of Turkey, and the diversity between analysed characters were investigated. For this purpose, 9 genotypes from three Vicia species: common vetch (Vicia sativa L.), Hungarian vetch (Vicia pannonica Crantz.) and Narbon vetch (Vicia narbonensis L.), were used. The experiment was carried out to determine total phenolic content (TPC), content of individual phenolic compounds, to determine ABTS(center dot+) and DPPH center dot scavenging activity and ferric-reducing antioxidant power (FRAP) in methanol and acetone extracts of seeds. The TPC of vetch extracts was in range 11.18-30.42 mg GAE g(-1) (in methanol extract) and 17.05-59.88 mg GAE g(-1) (in acetone extract). Two V. sativa genotypes Cvoe and Cvke stood out among the others with regard to high TPC and antioxidant activity. They also had the highest content of individual hydroxybenzoic acids and flavones. All extracts of V. narbonensis genotypes were characterised by absence of flavones and low TPC and antioxidant activity. GGE biplot analysis revealed the differences of Vicia genotypes based on phenolic compounds and antioxidant activity. The significant correlations among TEAC, FRAP and DPPH center dot scavenging activity and the content of hydroxybenzoic acids were found in both methanol and acetone extracts (P < 0.01). The genotypes were divided into three clusters in acetone extract and two clusters in methanol extract with similarity above 60% in each group by a hierarchical cluster analysis. These results demonstrated that the genotypic differences of Vicia species in terms of TPC and antioxidant activity can be a tool for feed technology studies for animal nutrition, animal welfare and meat quality.
