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Öğe Effect of Drying On Antioxidant Activity, Phenolic Compounds and Mineral Contents of Hawthorn and Wild Pear Fruits(Springer, 2020) Aladag, Mustafa Onur; Dogu, Suleyman; Uslu, Nurhan; Ozcan, Mehmet Musa; Gezgin, Sait; Dursun, NesimThe study demonstrated that SD-4 (3193.894mg GAE/100g) followed by SD-8 (2262.763mg GAE/100g) and SD-7 (1473.956mg GAE/100g) had the maximum total phenolic contents. SD-1 possessed the highest antioxidant activity, which later decreased from 83.067% in fresh fruit to 52.130% following drying. Across all fruits, drying resulted in significant reductions in both total phenolic content and phenolic compounds. Generally, gallic acid and (+)-catechin were the major phenolics in all fruits. Rutin trihydrate content of SD-4 decreased from 764.980mg/100g (fresh) to 0.620mg/100g when the fruit was dried. P, K, Ca, Mg and S were the macro elements of all fruits. Across all fruits, drying resulted in significant reductions in both total phenolic content and phenolic compounds. It was observed that dried fruits had the highest mineral contents compared to fresh fruits.Öğe The effect of heat treatment on phenolic compounds and fatty acid composition of Brazilian nut and hazelnut(Springer India, 2018) Ozcan, Mehmet Musa; Al Juhaimi, Fahad; Uslu, NurhanBrazilian peanut oil content increased with oven heating (65.08%) and decreased with microwave heating process (61.00%). While the phenolic content of untreated Brazilian nut was the highest of 68.97 mg GAE/100 g. Hazelnut (Sivri) contained the highest antioxidant activity (86.52%, untreated). Results reflected significantly differences between the antioxidant effect and total phenol contents of Brazilian nut and hazelnut (Sivri) kernels heated in the oven and microwave. Microwave heating caused a decrease in antioxidant activity of hazelnut. Gallic acid, 3,4-dihydroxybenzoic acid and (+)- and catechin were the main phenolic compounds of raw Brazilian nut with the value of 5.33, 4.33 and 4.88 mg/100 g, respectively, while the dominant phenolics of raw hazelnut (Sivri) kernels were gallic acid (4.81 mg/100 g), 3,4-dihydroxybenzoic acid (4.61 mg/100 g), (+)-catechin (6.96 mg/100 g) and 1,2-dihydroxybenzene (4.14 mg/100 g). Both conventional and microwave heating caused minor reduction in phenolic compounds. The main fatty acids of Brazilian nut oil were linoleic (44.39-48.18%), oleic (27.74-31.74%), palmitic (13.09-13.70%) and stearic (8.20-8.91%) acids, while the dominant fatty acids of hazelnut (Sivri) oil were oleic acid (80.84%), respectively. The heating process caused noticeable change in fatty acid compositions of both nut oils.Öğe The Effect of Heating Temperature on Total Phenolic Content, Antioxidant Activity, and Phenolic Compounds of Plum and Mahaleb Fruits(Walter De Gruyter Gmbh, 2019) Ghafoor, Kashif; Ahmed, Isam A. Mohamed; Dogu, Suleyman; Uslu, Nurhan; Fadimu, Gbemisola J.; Al Juhaimi, Fahad; Babiker, Elfadil E.The effect of heating at different temperatures (60, 80, 90,110, and 130 degrees C) on the total phenolic content, antioxidant activity, and phenolic compounds present in plum and mahaleb fruits was investigated. The antioxidant activity values and total phenolic contents of fresh plum (93.82% measured by DPPH method, 787.79 mg gallic acid equivalent (GAE)/100 g dry weight determined by Folin method) and mahaleb fruits (81.80%, 634.47 mg GAE /100 g dry weight) were higher than plum and mahaleb fruits dried at different temperatures (p < 0.05). Generally, the heating process caused a reduction in both total phenolic content and antioxidant activity for plum and mahaleb. While (+)-catechin (92.62 mg/kg), 1,2-dihydroxybenzene (132.15 mg/kg), gallic acid (107.01 mg/kg), and 3,4-dihydroxybenzoic acid (74.59 mg/kg) are the key phenolic compounds in fresh plum, (+)-catechin, 3,4-dihydroxybenzoic acid, 1,2-dihydroxybenzene, and syringic and caffeic acids were the major phenolic compounds of mahaleb fruits. The polyphenol content of fruits and the class of phenolics present are significantly affected by heating temperature.Öğe The Effect of Heating Temperature on Total Phenolic Content, Antioxidant Activity, and Phenolic Compounds of Plum and Mahaleb Fruits(Walter De Gruyter Gmbh, 2019) Ghafoor, Kashif; Ahmed, Isam A. Mohamed; Dogu, Suleyman; Uslu, Nurhan; Fadimu, Gbemisola J.; Al Juhaimi, Fahad; Babiker, Elfadil E.The effect of heating at different temperatures (60, 80, 90,110, and 130 degrees C) on the total phenolic content, antioxidant activity, and phenolic compounds present in plum and mahaleb fruits was investigated. The antioxidant activity values and total phenolic contents of fresh plum (93.82% measured by DPPH method, 787.79 mg gallic acid equivalent (GAE)/100 g dry weight determined by Folin method) and mahaleb fruits (81.80%, 634.47 mg GAE /100 g dry weight) were higher than plum and mahaleb fruits dried at different temperatures (p < 0.05). Generally, the heating process caused a reduction in both total phenolic content and antioxidant activity for plum and mahaleb. While (+)-catechin (92.62 mg/kg), 1,2-dihydroxybenzene (132.15 mg/kg), gallic acid (107.01 mg/kg), and 3,4-dihydroxybenzoic acid (74.59 mg/kg) are the key phenolic compounds in fresh plum, (+)-catechin, 3,4-dihydroxybenzoic acid, 1,2-dihydroxybenzene, and syringic and caffeic acids were the major phenolic compounds of mahaleb fruits. The polyphenol content of fruits and the class of phenolics present are significantly affected by heating temperature.Öğe Effect of species on total phenol, antioxidant activity and phenolic compounds of different wild onion bulbs(Springer, 2018) Ozcan, Mehmet Musa; Dogu, Suleyman; Uslu, NurhanThis study was focused on investigation of phenolic compounds, total phenolic contents and antioxidant activities of some wild onions (Crocus chrysanthus (SDA1), Hyacinthella campanislata (SDA2), Muscari armaniacum (SDA3), Ornithogalum armeniacum (SDA4), Gagea granatelli (SDA5), Hyacinthella heldreichii (SDA6), Muscari neglectum (SDA7), Ornithogalum lanceolatum (SDA-8). SDA-3 had the maximum total phenolic content, with the range of 88.19 mg/100 g, followed by SDA-1 (82.50 mg/100 g). SDA-1 (29.32%) exhibited the best antioxidant activity, followed by SDA-3 (27.92%). The major phenolic compound of SDA-3, SDA-4, SDA-5, SDA-6 and SDA-8 was (+)-catechin, with the ranges of 35.23, 30.76, 33.72, 44.42 and 50.85 mg/100 g, respectively. The dominant phenolic acid of SDA-1 (86.15 mg/100 g) and SDA-7 (22.07 mg/100 g) was determined as gallic acid. Additionally, SDA-2 contained the highest content of isorhamnetin (53.87 mg/100 g). Results indicate that the bulbs of studied plants are potential sources of phenolic compounds and their methanolic extracts have antioxidant activity.Öğe Essential oil composition of some Origanum species(Agrimedia Gmbh, 2017) Danton, Ombeline; Ozcan, Mehmet Musa; Figueredo, Gilles; Chalard, Pierre; Dogu, Suleyman; Uslu, Nurhan; Chalchat, Jean ClaudeChemical compositions of O.majorana, O. onites and O. saccatum oils were determined by GC and GC-MS. The yields of the essential oils were 0.276%, 0.395% and 0.261% v/w, respectively. The most abundant compounds of O.majorana, O. onites and O.saccatum oils were a-terpinene, p-cymene, gamma-terpinene and carvacrol. The highest carvacrol (10.920%) and linalool (10.271%) were found in O. onites oil. in addition, while myrcene is found as 10.471% and 4.817% in O. majorana and O. onites oils, respectively. Myrcene was determined as 0.662% in O.saccatum. The key component of Oregano species tested is p-cymene. The contents of p-cymene in O.majorana, O. onites and O. soccatum oils were determined as 33.416%, 17.417% and 73.143%, respectively. Also, gamma-terpinene contents of oil samples ranged from 17.798% (O. saccatum) to 29.932% (O. majorana).Öğe Pecan walnut (Carya illinoinensis (Wangenh.) K. Koch) oil quality and phenolic compounds as affected by microwave and conventional roasting(Springer India, 2017) Al Juhaimi, Fahad; Ozcan, Mehmet Musa; Uslu, Nurhan; Dogu, SuleymanIn this study, the effects of conventional and microwave roasting on phenolic compounds, free acidity, peroxide value, fatty acid composition and tocopherol content of pecan walnut kernel and oil was investigated. The oil content of pecan kernels was 73.78% for microwave oven roasted at 720 W and 73.56% for conventional oven roasted at 110 A degrees C. The highest free fatty acid content (0.50%) and the lowest peroxide value (2.48 meq O-2/kg) were observed during microwave roasting at 720 W. The fatty acid profiles and tocopherol contents of pecan kernel oils did not show significant differences compared to raw samples. Roasting process in microwave oven at 720 W caused the reduction of some phenolic compounds, while the content of gallic acid exhibited a significant increase.Öğe Variations in Bioactive Properties, Phenolic Compounds and Fatty Acid Compositions of Different Parts of Prickly Pear (Opuntia ficus-indica Spp) Fruits(Springer, 2023) Ozcan, Mehmet Musa; Uslu, Nurhan; Kara, Hasan Huseyin; Ozcan, Mustafa MeteThe peel, pulp and seeds of prickly pear fruits contained 84.3%, 82.98% and 5.78% moisture, respectively. Total carotenoid and total flavonoid contents of prickly pear fruit parts ranged between 0.02 mu g/kg (peel) and 1.11 mu g/kg (seed) to 14.52 mg per 100 g (pulp) and 68.33 mg per 100 g (seed), respectively. Total phenolic contents and antioxidant activities of prickly pear fruit parts were determined between 41.94 mg GAE per 100 g (seed) and 122.10 mg GAE per 100 g (peel) to 0.87% (pulp) and 1.68% (seed), respectively. In general, prickly pear fruit seed, peel and pulp are very rich in catechin and gallic acid. Gallic acid amounts of prickly pear fruit parts varied between 17.46 (pulp) and 27.70 mg per 100 g (peel). Catechin and rutin trihydrate contents of prickly pear fruit portions were identified between 36.74 (pulp) and 122.87 mg per 100 g (seed) to 1.35 mg per 100 g (peel) and 10.04 mg per 100 g (pulp), respectively. The prickly pear seed oil contained 11.99% palmitic, 3.51% stearic, 20.28% oleic and 62.50% linoleic acids.