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Öğe Antioxidant capacity and fatty acid composition of different parts of Adenocarpus complicatus (Fabaceae) from Turkey(Revista De Biologia Tropical, 2014) Berber, Adnan; Zengin, Gokhan; Aktumsek, Abdurrahman; Sanda, Murad Aydin; Uysal, TunaAdenocarpus complicatus is distributed throughout the Anatolian peninsula and is widely used for human and animal nutrition. The purpose of this work was to study the antioxidant properties and fatty acid composition of different parts of this plant (fruits and mixed materials). The species was collected from Golyuzu village of the Seydisehir district near Konya province, Turkey. Fruit and mixed parts obtained from this species were ground and a 15g sample was used to prepare methanolic extracts. Powdered plant samples were extracted with 100mL methanol in a mechanical shaker. The obtained extracts were filtered and concentrated to dryness under reduced pressure and were subsequently stored at -20 degrees C. Antioxidant components, namely total phenolic and flavonoid content, were detected for each extract using spectrophotometric methods. Antioxidant capacity was evaluated by various assays including phosphomolybdenum, DPPH free radical scavenging capacity, metal chelating activity, and ferric and cupric ion reducing power. The fatty acid profiles of plant parts were also determined by using gas chromatography. The total phenolic content of fruit (36.21mgGAE/g) was higher than that of mixed materials (13.79mgGAE/g). The methanolic extract of mixed material had higher amounts of flavonoid than fruit extract. The free radical scavenging activity of extracts was expressed as IC50 value (mu g/mL) (amount required to inhibit DPPH radical formation by 50%). The lower IC50 value reflects better free radical scavenging action. The radical scavenging activity of the samples was compared with BHT, it showed the mixed material to be almost two times more potent than the fruit extract. However, BHT is an excellent free radical scavenger with an IC50 of 34.061 mu g/mL. The ferric and cupric reducing power potentials of the extracts were expressed as EC50 value (the effective concentration at which the absorbance was 0.5). Fruit extract exhibited strong ferric reducing power with an EC50 of 871.25 mu g/mL. The metal chelating activity of the extracts increased with concentration. Chelating effect was 83.60% for fruit extract at 1mg/mL concentration. Oil content of fruit and mixed parts were detected as 6.71 and 6.14%, respectively. A total of 32 fatty acids were found in the oil. Essential fatty acids (linoleic and alpha-linolenic acid) were identified as the most abundant fatty acids in the oil. These results demonstrated that this plant species can be considered as an alternative to synthetic antioxidants. Likewise, the oil obtained from the plant can be used as a source of essential fatty acids for food and pharmacological applications.Öğe Antioxidant capacity and fatty acid composition of different parts of Adenocarpus complicatus (Fabaceae) from Turkey(Revista De Biologia Tropical, 2014) Berber, Adnan; Zengin, Gokhan; Aktumsek, Abdurrahman; Sanda, Murad Aydin; Uysal, TunaAdenocarpus complicatus is distributed throughout the Anatolian peninsula and is widely used for human and animal nutrition. The purpose of this work was to study the antioxidant properties and fatty acid composition of different parts of this plant (fruits and mixed materials). The species was collected from Golyuzu village of the Seydisehir district near Konya province, Turkey. Fruit and mixed parts obtained from this species were ground and a 15g sample was used to prepare methanolic extracts. Powdered plant samples were extracted with 100mL methanol in a mechanical shaker. The obtained extracts were filtered and concentrated to dryness under reduced pressure and were subsequently stored at -20 degrees C. Antioxidant components, namely total phenolic and flavonoid content, were detected for each extract using spectrophotometric methods. Antioxidant capacity was evaluated by various assays including phosphomolybdenum, DPPH free radical scavenging capacity, metal chelating activity, and ferric and cupric ion reducing power. The fatty acid profiles of plant parts were also determined by using gas chromatography. The total phenolic content of fruit (36.21mgGAE/g) was higher than that of mixed materials (13.79mgGAE/g). The methanolic extract of mixed material had higher amounts of flavonoid than fruit extract. The free radical scavenging activity of extracts was expressed as IC50 value (mu g/mL) (amount required to inhibit DPPH radical formation by 50%). The lower IC50 value reflects better free radical scavenging action. The radical scavenging activity of the samples was compared with BHT, it showed the mixed material to be almost two times more potent than the fruit extract. However, BHT is an excellent free radical scavenger with an IC50 of 34.061 mu g/mL. The ferric and cupric reducing power potentials of the extracts were expressed as EC50 value (the effective concentration at which the absorbance was 0.5). Fruit extract exhibited strong ferric reducing power with an EC50 of 871.25 mu g/mL. The metal chelating activity of the extracts increased with concentration. Chelating effect was 83.60% for fruit extract at 1mg/mL concentration. Oil content of fruit and mixed parts were detected as 6.71 and 6.14%, respectively. A total of 32 fatty acids were found in the oil. Essential fatty acids (linoleic and alpha-linolenic acid) were identified as the most abundant fatty acids in the oil. These results demonstrated that this plant species can be considered as an alternative to synthetic antioxidants. Likewise, the oil obtained from the plant can be used as a source of essential fatty acids for food and pharmacological applications.Öğe Antioxidant potentials and anticholinesterase activities of methanolic and aqueous extracts of three endemic Centaurea L. species(Pergamon-Elsevier Science Ltd, 2013) Aktumsek, Abdurrahman; Zengin, Gokhan; Guler, Gokalp Ozmen; Cakmak, Yavuz Selim; Duran, AhmetThe methanol and aqueous extracts of three endemic Centaurea species (C. polypodiifolia var. pseudobehen, C pyrrhoblephara and C antalyense) were investigated for their antioxidant and cholinesterase inhibitory activities. The antioxidant activities of these extracts were evaluated by in vitro models including, phosphomolybdenum assay, free radical scavenging assays (DPPH and ABTS), beta-carotene/linoleic acid test system, metal chelating assay, FRAP assay, ferric and cupric reducing power. Cholinesterase inhibitory activities were examined using Ellman's calorimetric method. Total phenol, flavonoid, and saponin contents were also measured. Among the six Centaurea extracts evaluated, the highest antioxidant abilities were obtained from C polypodiifolia var. pseudobehen. Methanolic extracts from C polypodiifolia var. pseudobehen and C antalyense had a noticeable inhibition towards AChE and BChE. These findings suggest that Centaurea species could be an anticholinesterase agent and antioxidant resource in some industries, such as food, pharmacology, and cosmetics. (C) 2013 Elsevier Ltd. All rights reserved.Öğe Assessment of the antioxidant potential and fatty acid composition of four Centaurea L. taxa from Turkey(Elsevier Sci Ltd, 2013) Aktumsek, Abdurrahman; Zengin, Gokhan; Guler, Gokalp Ozmen; Cakmak, Yavuz Selim; Duran, AhmetThis paper focused on the assessment of antioxidant property and fatty acid composition of four Centaurea species. The antioxidant activity of its methanol extract was evaluated by several in vitro experiments including phosphomolybedum assay, DPPH assay, beta-carotene/linoleic acid, ferric and cupric reducing power. Total phenolic and flavonoid contents were also evaluated. The methanol extract of Centaurea pulcherrima var. pulcherrima showed the superior free radical scavenging activity, linoleic acid inhibition capacity, reducing power and also had the highest total phenolic content. A significant relationship between antioxidant capacity and total phenolic components was found. The oils of Centaurea taxa were also analysed for fatty acid concentration by gas chromatography. The principal fatty acids in the species were palmitic acid (23.38-30.49%) and linoleic acid (20.19-29.93%). These findings suggest that the Centaurea species could be used as a potential source of new natural antioxidants and unsaturated fatty acids in food industry, cosmetics and pharmaceutical preparations. (c) 2013 Elsevier Ltd. All rights reserved.Öğe Bioactive constituents of Lathyrus czeczottianus and ethyl acetate and water extracts and their biological activities: An endemic plant to Turkey(Elsevier, 2021) Ceylan, Ramazan; Zengin, Gokhan; Guler, Gokalp Ozmen; Aktumsek, AbdurrahmanLathyrus species are economically important as food, fodder, and folk medicine. The antioxidant properties (radical scavenging effectiveness, reducing power potentials, metal chelating ability, phosphomolydenum capacity) phytochemical characterization (phenolic composition), and enzyme inhibition abilities of the water and ethyl acetate extracts of Lathyrus czeczottianus (LC) were tested. The phenolic ingradients of LC extracts were evaluated by HPLC-DAD (High-performance liquid chromatography with diode array detector). Chlorogenic acid, epicatechin, and benzoic acid were found as main phenolic compounds in both extracts. Generally, the water extract revealed strong antioxidant potential. The antioxidant effectiveness could be explained by high total phenolic level in the extract. Regarding enzyme inhibitory results, the ethyl acetate extract indicated good inhibitory activities on cholinesterase (for AChE: Acetylccholinesterase 1.15 mg galathamine equivalents (GALAE/g extract) and for BChE: Butyrylcholinesterase 0.19 mg GALAE/g extrac), tyrosinase (54.48 mg kojic acid equivalents (KAE/g)), and alpha-amylase (0.34 mmol acarbose equivalents (ACEs/g)), while the water extract had just good inhibition on alpha-glucosidase (6.49 mmol ACEs/g). In conclusion, L. czeczottianus could be good valuable of bioactive molecules for pharmaceuticals, food and agriculture, and nutraceutical applications. (C) 2020 SAAB. Published by Elsevier B.V. All rights reserved.Öğe Chemical and biological fingerprints of two Fabaceae species (Cytisopsis dorycniifolia and Ebenus hirsuta): Are they novel sources of natural agents for pharmaceutical and food formulations?(Elsevier Science Bv, 2016) Ceylan, Ramazan; Katanic, Jelena; Zengin, Gokhan; Matic, Sanja; Aktumsek, Abdurrahman; Boroja, Tatjana; Stanic, SnezanaIn the present study, the methanolic extracts of Cytisopsis dorycniifolia and Ebenus hirsuta were analyzed for antioxidant, enzyme inhibitory, antimicrobial and antigenotoxic activities. The identification and quantification of phenolic compounds in these extracts were performed using liquid chromatography coupled with mass spectrometry (LC-MS/MS) technique, and the main components were hyperoside, rutin, hesperidin, tannic acid and p-coumaric acid. The extracts had remarkable biological effects. Generally, C. dorycniifolia had higher level of bioactive components and exhibited stronger in vitro antioxidant effects than E. hirsuta. E. hirsuta was active especially against bacteria Pseudomonas fluorescens and Agrobacterium tumefaciens and fungi Puncturella fastigiata, while C dorycniifolia was active against bacteria E. faecalis and had moderate activity against Trichoderma species. The extracts displayed strong antigenotoxic effects (98.6% for E. hirsuta and 76.3% for C dorycniifolia). Our findings suggested that C dorycniifolia and E. hirsuta could be beneficial for the preparation of high-value pharmaceuticals and functional food ingredients. (C) 2016 Elsevier B.V. All rights reserved.Öğe Comparison of Fatty Acid Compositions and ?3/?6 Ratios of Wild Brown Trout and Cultured Rainbow Trout(Central Fisheries Research Inst, 2017) Guler, Gokalp Ozmen; Zengin, Gokhan; Cakmak, Yavuz Selim; Aktumsek, AbdurrahmanFish are a unique dietary source beneficial to human health. These valuable effects originate from omega 3 polyunsaturated fatty acids, particularly the eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) in the fish oil. In this study, fatty acid composition of the muscle lipids of Salmo trutta macrostigma (wild brown trout) and Oncorhynchus mykiss (cultured rainbow trout) in Gezende Dam Lake were determined by gas chromatographic technique. In both species, palmitic acid (16.26-18.94%), oleic acid (17.88-20.49%) and DHA (14.08-18.49%) were identified as major saturated fatty acid (SFA), monounsaturated fatty acid (MUFA) and polyunsaturated fatty acid (PUFA), respectively. Wild fish contained significantly more linolenic acid, arachidonic acid, eicosapentaenoic acid, docosapentaenoic acid, total omega 3 fatty acids and has higher omega 3/omega 6 ratio than cultured fish. In conclusion, wild brown trout may have a higher nutritional value considering total omega 3 fatty acids (35.52-27.43%) and omega 3/omega 6 ratio (3.84-1.56) compared to cultured rainbow trout.Öğe Enzyme Inhibitory Properties, Antioxidant Activities, and Phytochemical Profile of Three Medicinal Plants from Turkey(Hindawi Ltd, 2015) Zengin, Gokhan; Guler, Gokalp Ozmen; Aktumsek, Abdurrahman; Ceylan, Ramazan; Picot, Carene Marie Nancy; Mahomoodally, M. FawziWe aimed to investigate the inhibitory potential of three medicinal plants (Hedysarum varium, Onobrychis hypargyrea, and Vicia truncatula) from Turkey against key enzymes involved in human pathologies, namely, diabetes (alpha-amylase and alpha-glucosidase), neurodegenerative disorders (tyrosinase, acetylcholinesterase, and butyrylcholinesterase), and hyperpigmentation (tyrosinase). The antioxidant potential, phenolic and flavonoid content of ethyl acetate, and methanolic and aqueous extracts were investigated using in vitro assays. The total antioxidant capacity (TAC), beta-carotene/linoleic acid bleaching activity, 1,1-diphenyl-2-picrylhydrazyl free radical (DPPH center dot), 2,2-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS(center dot+)), cupric ion reducing antioxidant capacity (CUPRAC), ferric reducing antioxidant power (FRAP), and metal chelating activity on ferrous ions were used to evaluate the antioxidant capabilities of the extracts. The half-maximal inhibitory concentrations (IC50) of the extracts on cholinesterase, tyrosinase, and alpha-amylase were significantly higher than the references, galantamine, kojic acid, and acarbose, respectively. The half-maximal effective concentrations (EC50) of the extracts on TAC, CUPRAC, and FRAP were significantly higher than trolox. The phenol and flavonoid contents of the plant extracts were in the range 20.90 +/- 0.190-83.25 +/- 0.914mg gallic acid equivalent/g extract and 1.45 +/- 0.200-39.71 +/- 0.092mg rutin equivalent/g extract, respectively. The plants were found to possess moderate antioxidant capacities and interesting inhibitory action against key enzymes.Öğe Evaluation of Fatty Acid Compositions of Yogurts in Turkey(Asian Journal Of Chemistry, 2014) Caglayan, Okan; Cakmak, Yavuz Selim; Guler, Gokalp Ozmen; Zengin, Gokhan; Aktumsek, AbdurrahmanIn this study, fatty acid composition and conjugated linoleic acid content of some yogurts in Turkey were determined. Total 50 yogurt samples belonging to 16 different national yogurt brands were analyzed by using GC. These samples categorized as whole yogurts, light yogurts, probiotic yogurts and fruity yogurts. Generally, palmitic acid (28.840-30.160 %), oleic acid (26.003-27.533 %) and stearic acid (11.413-12.077 %) were major fatty acids. Total conjugated linoleic acid percentages varied between 0.790 and 0.862 %. The results have shown that fatty acids compositions of yogurts have a desirable characteristic for healthy diet when their levels of conjugated linoleic acid contents are considered.Öğe Evaluation of Fatty Acid Compositions of Yogurts in Turkey(Asian Journal Of Chemistry, 2014) Caglayan, Okan; Cakmak, Yavuz Selim; Guler, Gokalp Ozmen; Zengin, Gokhan; Aktumsek, AbdurrahmanIn this study, fatty acid composition and conjugated linoleic acid content of some yogurts in Turkey were determined. Total 50 yogurt samples belonging to 16 different national yogurt brands were analyzed by using GC. These samples categorized as whole yogurts, light yogurts, probiotic yogurts and fruity yogurts. Generally, palmitic acid (28.840-30.160 %), oleic acid (26.003-27.533 %) and stearic acid (11.413-12.077 %) were major fatty acids. Total conjugated linoleic acid percentages varied between 0.790 and 0.862 %. The results have shown that fatty acids compositions of yogurts have a desirable characteristic for healthy diet when their levels of conjugated linoleic acid contents are considered.Öğe Shedding light on the biological and chemical fingerprints of three Achillea species (A-biebersteinii, A-millefolium and A-teretifolia)(Royal Soc Chemistry, 2017) Zengin, Gokhan; Aktumsek, Abdurrahman; Ceylan, Ramazan; Uysal, Sengul; Mocan, Andrei; Guler, Gokalp Ozmen; Mahomoodally, M. FawziRepresentatives of the Achillea genus are widely used as foods or nutraceuticals. Considering the increasing demand for herbal dietary supplements with health promoting effects, the objective of this research was to evaluate the biological and chemical profiles of different extracts (ethyl acetate, methanol and water) obtained from three Achillea species (A. biebersteinii, A. millefolium and A. teretifolia). The antioxidant (free radical scavenging (DPPH and ABTS), reducing power (CUPRAC and FRAP), metal chelating and phosphomolybdenum), enzyme inhibitory (anti-cholinesterase, anti-tyrosinase, anti-amylase and anti-glucosidase) and antimicrobial (antibacterial and antifungal) effects were assessed to investigate their biological profiles. Moreover, the total phenolic and flavonoid contents were determined and LC-MS analysis was performed for the chemical profile of the investigated extracts. The LC-MS analysis revealed the presence of several caffeoylquinic acids in these extracts. Generally, the methanol and water extracts exhibited stronger antioxidant abilities, which correlated with the higher levels of phenolic compounds when compared to the ethyl acetate extracts. In addition, the best antimicrobial activities were obtained for the ethyl acetate and methanolic extracts. However, the ethyl acetate extract had remarkable enzyme inhibitory potential. On the basis of our results, Achillea species may be promoted as promising sources of natural agents and used for the development of nutraceuticals or functional food ingredients.Öğe A STUDY ON ANTIOXIDANT CAPACITIES AND FATTY ACID COMPOSITIONS OF TWO DAPHNE SPECIES FROM TURKEY: NEW SOURCES OF ANTIOXIDANTS AND ESSENTIAL FATTY ACIDS(Wiley, 2013) Zengin, Gokhan; Arkan, Tuba; Aktumsek, Abdurrahman; Guler, Gokalp Ozmen; Cakmak, Yavuz SelimDaphne (Thymealaceae) species have been widely used in traditional Anatolian medicine. The antioxidant capacity and fatty acid composition of two Daphne taxa (D.oleoides subsp. oleoides and D.serica) were studied. The antioxidant properties of four solvent extracts of Daphne species were assessed using different chemical assays including phosphomolybdate assay, free radical-scavenging assay, -carotene/linoleic acid test system, ferric and cupric reducing power. The total phenolic and flavonoid content of the extracts also were determined. Ethyl acetate, methanol and ethanol extracts obtained from the Daphne species possess strong antioxidant potential. Polyunsaturated fatty acids in the studied oils were the highest level in the fatty acid components. Essential fatty acids accounted for 27.46-45.31% of total fatty acids. These results indicated that the extracts of studied Daphne taxa can be exploited as a source of natural antioxidants and essential fatty acids in pharmacological and food industry.