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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 Determination of fatty acid profiles of total, neutral, and polar lipids in different tissues of Vimba vimba (L., 1758) from Egirdir Lake (Isparta, Turkey)(Tubitak Scientific & Technological Research Council Turkey, 2013) Gorgun, Salih; Akpinar, Nukhet; Zengin, Gokhan; Akpinar, Mehmet Ali; Gunlu, Ali; Guler, Gokalp Ozmen; Aktumsek, ApdurahmanFatty acid profiles of total, neutral, and polar lipids in the liver, muscle, and intestine of female individuals of Vimba vimba (L., 1758) were determined by gas chromatography. C16:0, C16: 1 n-7, C18:1 n-7, and C18:1 n-9 were the most abundant fatty acids in total and neutral lipids in all tissues investigated. In addition to these acids, C20:4 n-6 (arachidonic acid) and C22:6 n-3 (docosahexaenoic acid) were the other fatty acids having high percentages in the polar lipid fraction of the tissues. The highest and lowest n-3 to n-6 ratios, which are a good indicator of the quality of fish oils, were determined in the muscle (1.68) and liver (0.68) in the polar lipid fraction, respectively. It was determined that the species had low levels of the n-3 forms of polyunsaturated fatty acids in the investigated tissues. For a better understanding of fatty acid metabolism of V. vimba, more detailed studies are required in terms of feeding experiments.Öğe Elucidation of chemical compounds in different extracts of two Lavandula taxa and their biological potentials: Walking with versatile agents on the road from nature to functional applications(Elsevier, 2023) Zengin, Gokhan; Yagi, Sakina; Selvi, Selami; Cziaky, Zoltan; Jeko, Jozsef; Sinan, Kouadio Ibrahime; Topcu, Asena AyyueceDue to their health-promoting and nutraceutical properties, lavenders are frequently employed in the food and pharmaceutical industries. Here, we focused on investigate the chemical profile of hexane, MeOH, and water extracts of leaf, flower, and root of L. pedunculata and L. stoechas and to assess their antioxidant, enzyme inhibitory, and antibacterial properties. The highest total polyphenolic and flavonoids contents were recorded from the water and MeOH extracts of the leaf and flower of L. stoechas, respectively. Our HPLC/MS/MS analysis detected over 90 secondary metabolites, consisting of both known and novel terpenoids, polyphenols, flavonoids, and their derivative. Water leaf extract of L. stoechas displayed significantly (p < 0.05) the highest antiradical, Cu2+ and Fe3+ reducing capacity while hexane extract of the leaf and MeOH extract of the flower of L. pedunculata revealed the best metal chelating ability and total antioxidant activity respectively. The hexane extract of the leaf of L. pedunculata exerted the highest acetylcholinesterase and tyrosinase inhibition activity, whereas the hexane extracts from L. stoechas leaf and L. pedunculata root recorded the highest ability to inhibit the butyrylcholinesterase and alpha-amylase enzymes respectively. The water extracts of the leaf of the two species, besides the hexane extract of the leaf of L. pedunculata exerted the best inhibition effect against the alpha-glucosidase. The sensitivities of Gram-positive and Gram-negative bacteria species against different extracts at two different concentrations were tested based on agar well diffusion assay. According to the result, we found that the nhexane extract of L. stoechas-flowers showed the highest antibacterial activity. In conclusion, the results suggest that both Lavandula species have promising potential as sources of bioactive agents for various industrial applications.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 Exogenous hesperidin and chlorogenic acid alleviate oxidative damage induced by arsenic toxicity in Zea mays through regulating the water status, antioxidant capacity, redox balance and fatty acid composition(Elsevier Sci Ltd, 2022) Arikan, Busra; Ozfidan-Konakci, Ceyda; Yildiztugay, Evren; Zengin, Gokhan; Alp, Fatma Nur; Elbasan, FevziArsenic (As) toxicity is a problem that needs to be solved in terms of both human health and agricultural production in the vast majority of the world. The presence of As causes biomass loss by disrupting the balance of biochemical processes in plants and preventing growth/water absorption in the roots and accumulating in the edible parts of the plant and entering the food chain. A critical method of combating As toxicity is the use of biosafe, natural, bioactive compounds such as hesperidin (HP) or chlorogenic acid (CA). To this end, in this study, the physiological and biochemical effects of HP (100 mu M) and CA (50 mu M) were investigated in Zea mays under arsenate stress (100 mu M). Relative water content, osmotic potential, photosynthesis-related parameters were suppressed under stress. It was determined that stress decreased the activities of the antioxidant system and increased the level of saturated fatty acids and, gene expression of PHT transporters involved in the uptake and translocation of arsenate. After being exposed to stress, HP and CA improved the capacity of superoxide dismutase (SOD), catalase (CAT), peroxidase (POX), glutathione S-transferase (GST) and glutathione peroxidase (GPX) and then ROS accumulation (H2O2) and lipid peroxidation (TBARS) were effectively removed. These phenolic compounds contributed to maintaining the cellular redox status by regulating enzyme/non-enzyme activity/contents involved in the AsA-GSH cycle. HP and CA reversed the adverse effects of excessive metal ion accumulation by re-regulated expression of the PHT1.1 and PHT1.3 genes in response to stress. Exogenously applied HP and CA effectively maintained membrane integrity by regulating saturated/unsaturated fatty acid content. However, the combined application of HP and CA did not show a synergistic protective activity against As stress and had a negative effect on the antioxidant capacity of maize leaves. As a result, HP and CA have great potentials to provide tolerance to maize under As stress by reducing oxidative injury and preserving the biochemical reactions of photosynthesis.Öğe Glutamate, Humic Acids and Their Combination Modulate the Phenolic Profile, Antioxidant Traits, and Enzyme-Inhibition Properties in Lettuce(Mdpi, 2023) De Gregorio, Marco Armando; Zengin, Gokhan; Alp-Turgut, Fatma Nur; Elbasan, Fevzi; Ozfidan-Konakci, Ceyda; Arikan, Busra; Yildiztugay, EvrenLettuce (Lactuca sativa L., Asteraceae) is a popular vegetable leafy crop playing a relevant role in human nutrition. Nowadays, novel strategies are required to sustainably support plant growth and elicit the biosynthesis of bioactive molecules with functional roles in crops including lettuce. In this work, the polyphenolic profile of lettuce treated with glutamic acid (GA), humic acid (HA), and their combination (GA + HA) was investigated using an untargeted metabolomics phenolic profiling approach based on high-resolution mass spectrometry. Both aerial and root organ parts were considered, and a broad and diverse phenolic profile could be highlighted. The phenolic profile included flavonoids (anthocyanins, flavones, flavanols, and flavonols), phenolic acids (both hydroxycinnamics and hydroxybenzoics), low molecular weight phenolics (tyrosol equivalents), lignans and stilbenes. Overall, GA and HA treatments significantly modulated the biosynthesis of flavanols, lignans, low molecular weight phenolics, phenolic acids, and stilbene. Thereafter, antioxidant capacity was evaluated in vitro with 2,2-diphenyln-1-picrylhydrazyl (DPPH), 2,2'-Azino-bis(3-ethylbenzthiazoline-6-sulfonic acid) (ABTS), ferric reducing antioxidant power (FRAP), and cupric ion reducing antioxidant capacity (CUPRAC) assays. In addition, this study examined the inhibitory properties of enzymes, including acetylcholinesterase (AChE) and butyrylcholinesterase (BChE), tyrosinase, alpha-amylase, and alpha-glucosidase. Compared to individual treatments, the combination of GA + HA showed stronger antioxidant abilities in free radical scavenging and reducing power assays in root samples. Moreover, this combination positively influenced the inhibitory effects of root samples on AChE and BChE and the tyrosinase inhibitory effect of leaf samples. Concerning Pearson's correlations, antioxidant and enzyme inhibition activities were related to phenolic compounds, and lignans in particular correlated with radical scavenging activities. Overall, the tested elicitors could offer promising insights for enhancing the functional properties of lettuce in agricultural treatments.Öğe The hormetic dose-risks of polymethyl methacrylate nanoplastics on chlorophyll a fluorescence transient, lipid composition and antioxidant system in Lactuca sativa(Elsevier Sci Ltd, 2022) Yildiztugay, Evren; Ozfidan-Konakci, Ceyda; Arikan, Busra; Alp, Fatma Nur; Elbasan, Fevzi; Zengin, Gokhan; Cavusoglu, HalitNanoplastic pollution has become an increasing problem due to over-consumption and degradation in ecosystems. A little is known about ecological toxicity and the potential risks of nanoplastics on plants. To better comprehend the hormetic effects of nanoplastics, the experimental design was conducted on the impacts of polymethyl methacrylate (PMMA) on water status, growth, gas exchange, chlorophyll a fluorescence transient, reactive oxygen species (ROS) content (both content and fluorescence visualization), lipid peroxidation and antioxidant capacity (comparatively between leaves and roots). For this purpose, PMMA (10, 20, 50 and 100 mg L-1) was hydroponically applied to Lactuca sativa for 15 days(d). PMMA exposure resulted a decline in the growth, water content and osmotic potential. As based on assimilation rate (A), stomatal conductance (g(s)), and intercellular CO2 concentrations (C-i), the decreased stomatal limitation (L-s) and, A/C-i and increased intrinsic mesophyll efficiency proved low carboxylation efficiency showing impaired photosynthesis as a non-stomatal limitation. PMMA toxicity increased the trapping fluxes and absorption with a decrease in electron transport fluxes caused the disruption in reaction centers of photosystems. The leaves and roots had a similar effect against PMMA toxicity, with increased superoxide dismutase (SOD) activity. Although, catalase (CAT) and peroxidase (POX) of leaves increased under 10 mg L-1 PMMA, these defense activities failed to prevent radicals from attacking. Compared to the leaves, the lettuce roots showed an intriguing result for AsA-GSH cycle against PMMA exposure. In the roots, the lowest PMMA application provided the high ascorbate/dehydroascorbate (AsA/DHA), GSH/GSSG and the pool of AsA/glutathione (GSH) and non-suppressed GSH redox state. Also, 10 mg L-1 PMMA helped remove high hydrogen peroxide (H2O2) by both glutathione peroxidase (GPX) and glutathione S-transferase (GST). Since this improvement in the antioxidant system could not be continued in roots after higher applications than 20 mg L-1 PMMA, TBARS (Thiobarbituric acid-reactive substances), indicating the level of lipid peroxidation, and H2O2 increased. Our findings obtained from PMMA-applied lettuce provide new information to advance the tolerance mechanism against nanoplastic pollution.Öğe HPLC-DAD profiles and pharmacological insights of Onobrychis argyrea subsp isaurica extracts(Elsevier Sci Ltd, 2018) Guler, Gokalp Ozmen; Zengin, Gokhan; Karadag, Firat; Monica, Adriano; Picot, Carene Marie Nancy; Mahomoodally, Mohamad FawziOnobrychis argyrea Boiss. subsp. Isaurica (Fabaceae), endemic to the eastern Mediterranean region, is a poorly studied medicinal plant. This study sets out to investigate into antioxidant and inhibitory activities of O. argyrea extracts (ethyl acetate, methanol, and water) against key enzymes linked to diabetes (alpha-amylase, alpha-glucosidase), Alzheimer's disease (acetylcholinesterase, butyrylcholinesterase), and skin hyperpigmentation (tyrosinase). Phytochemical composition was determined by HPLC-DAD and in silico approach used to provide additional insight of the possible interaction of the identified phenolic compounds with the studied enzymes. The methanol extract showed potent inhibitory action against acetylcholinesterase (1.55 mg GALAE/g extract), tyrosinase (61.61 mg KAE/g extract), and glucosidase (20.17 mmol ACAE/g extract). The methanol extract of O. argyrea exhibited potent radical scavenging potential (126.51 mg TE/g extract for DPPH scavenging assay) and reducing capacities (311.36 and 200.70 mg TE/g extract, for CUPRAC and FRAP assays, respectively). Quercetin, apigenin, and benzoic acid were identified in significant amounts in the methanol extract of O. argyrea. Quercetin interacted with the catalytic pocket of glucosidase by establishing hydrogen bonds with Ser157, Ser241, Asp307, and pi-pi interactions with His280 and Tyr158. The observed inhibitory effects of O. argyrea extracts on the studied enzyme suggest that this plant could be a promising source of naturally occurring chemical compounds for the management of diabetes, Alzheimer's disease, skin hyperpigmentation disorders, as well as, oxidative stress-related complications.Öğe Rosmarinic acid and hesperidin regulate gas exchange, chlorophyll fluorescence, antioxidant system and the fatty acid biosynthesis-related gene expression in Arabidopsis thaliana under heat stress(Pergamon-Elsevier Science Ltd, 2022) Arikan, Busra; Ozfidan-Konakci, Ceyda; Alp, Fatma Nur; Zengin, Gokhan; Yildiztugay, EvrenThe impacts of exogenous rosmarinic acid (RA, 100 mu M) and/or hesperidin (HP, 100 mu M) were evaluated in improving tolerance on the gas exchange, chlorophyll fluorescence and efficiencies, phenomenological fluxes of photosystems, antioxidant system and gene expression related to the lipid biosynthesis under heat stress. For this purpose, Arabidopsis thaliana was grown under RA and HP with heat stress (S, 38 ?) for 24 h(h). As shown in gas exchange parameters, heat stress caused mesophyll efficiency and non-stomatal restrictions. Both alone and combined forms of RA and HP to stress-treated A. thaliana alleviated the disturbance of carbon assimilation, transpiration rate and internal CO2 concentrations. Stress impaired the levels of energy flow reaching reaction centers of PSII and the photon capture ability of active reaction centers. RA and/or HP enhanced photosystems' structural/functional characteristics and photosynthetic performance. Histochemical staining and biochemical analyses revealed that heat stress caused the oxidation in A. thaliana. By activating several defensive mecha-nisms, RA and/or HP could reverse the harm caused by radical production. Both alone and combined forms of RA and HP removed superoxide anion radical (O-2 & BULL;-) accumulation, inducing superoxide dismutase (SOD). The common enzyme that scavenged hydrogen peroxide (H2O2) at all three applications (S + RA, S + HP and S + RA + HP) was POX. Also, only RA could utilize the ascorbate (AsA) regeneration in response to stress, suggesting increased ascorbate peroxidase (APX), monodehydroascorbate (MDHAR) and dehydroascorbate (DHAR) activ-ities. However, the regeneration/redox state of AsA and glutathione (GSH) did not maintain under S + HP and S + RA + HP. While RA had no positive influence on the saturated fatty acids under stress, HP increased the total saturated fatty acids (primarily palmitic acid). Besides, the combined application of RA + HP effectively created the stress response by increasing the expression of genes involved in fatty acid synthesis. The synergetic in-teractions of RA and HP could explain the increased levels of saturated fatty acids in combining these com-pounds. The data obtained from the study will contribute to the responses of phenolic compounds in plants to heat stress.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.Öğe Traditionally Used Lathyrus Species: Phytochemical Composition, Antioxidant Activity, Enzyme Inhibitory Properties, Cytotoxic Effects, and in silico Studies of L-czeczottianus and L-nissolia(Frontiers Media Sa, 2017) Llorent-Martinez, Eulogio J.; Zengin, Gokhan; Cordova, Maria L. Fernandez-De; Bender, Onur; Atalay, Arzu; Ceylan, Ramazan; Mollica, AdrianoMembers of the genus Lathyrus are used as food and as traditional medicines. In order to find new sources of biologically-active compounds, chemical and biological profiles of two Lathyrus species (L. czeczottianus and L. nissolia) were investigated. Chemical profiles were evaluated by HPLC-ESI-MSn, as well as by their total phenolic and flavonoid contents. In addition, antioxidant, enzyme inhibitory, and cytotoxic effects were also investigated. Antioxidant properties were tested by using different assays (DPPH, ABTS, CUPRAC, FRAP, phosphomolybdenum, and metal chelation). Cholinesterases (AChE and BChE), tyrosinase, alpha-amylase, and alpha-glucosidase were used to evaluate enzyme inhibitory effects. Moreover, vitexin (apigenin-8-C-glucoside) and 5-O-caffeoylquinic acid were further subjected to molecular docking experiments to provide insights about their interactions at molecular level with the tested enzymes. In vitro cytotoxic effects were examined against human embryonic kidney cells (HEK293) by using iCELLigence real time cell analysis system. Generally, L. czeczottianus exhibited stronger antioxidant properties than L. nissolia. However, L. nissolia had remarkable enzyme inhibitory effects against cholinesterase, amylase and glucosidase. HPLC-ESI-MSn analysis revealed that flavonoids were major components in these extracts. On the basis of these results, Lathyrus extracts were rich in biologically active components; thus, these species could be utilized to design new phytopharmaceutical and nutraceutical formulations.