Browsing by Author "Ozer M.S."
Now showing 1 - 20 of 25
Results Per Page
Sort Options
Item Enhanced optical oxygen sensing using a newly synthesized ruthenium complex together with oxygen carriers(Elsevier, 2003) Ertekin K.; Kocak S.; Ozer M.S.; Aycan S.; Cetinkaya B.In this article, an emission based, simple and fast method is proposed for the determination of gaseous oxygen. A newly synthesized fluorophore, dichloro-{2,6-bis[1-(4-dimethylamino-phenylimino) ethyl]pyridine}ruthenium(II) has been used for oxygen sensing together with oxygen carrier perfluorochemicals (PFCs) in silicon matrix. It should be noted that the solubility of oxygen in fluorocarbons is about three to ten times large as that observed in the parent hydrocarbons or in water, respectively. Employed PFCs are chemically and biochemically inert, have high dissolution capacities for oxygen, and, once doped into sensing film, considerably enhance the response of sensing agent. © 2003 Elsevier B.V. All rights reserved.Item Determination of pK a values of clinically important perfluorochemicals in nonaqueous media(2008) Hakli O.; Ertekin K.; Ozer M.S.; Aycan S.Perfluorochemicals (PFCs) are clinically and biotechnologically important species. In this work, the potentiometric titration method in nonaqueous media is proposed for the determination of acidity constant values of six different perfluorinated compounds. The saturated and nonsaturated perfluoroacids, perfluorocarnosine, and perfluoroalkyl-β-alanine were potentiometrically titrated in acetonitrile, N,N-dimethylformamide, acetone, ethanol, methanol, and pyridine with tetrabutylammonium hydroxide. The half-neutralization potentials and acidity constants of PFCs have been calculated from the titration curves by using the computerized derivative method. Except for RF-Carnosine, all of the potentiometric titration curves of the PFCs exhibited one stoichiometric and well-defined endpoints in all of the solvents employed. The reproducibility and sensitivity of the method were evaluated. © 2008 MAIK Nauka.Item Essential oil composition and antioxidant activities of alkanet (Alkanna tinctoria subsp. tinctoria)(2010) Ozer M.S.; Sarikurkcu C.; Tepe B.; Can S.This study is designed to examine the chemical composition and in vitro antioxidant activity of the hydrodistillated essential oil and the various extracts of alkanet (Alkanna tinctoria subsp. tinctoria). Gas chromatography (GC) and GC-mass spectrometry (GC-MS) analysis of the essential oil were resulted in the determination of 27 different compounds, representing 93.32% of the total oil. The major compounds detected in the oil, were pulegone (22.27%), 1,8-cineole (13.03%), α-terpinyl acetate (6.87%), and isophytol (6.83%), respectively. Antioxidant activities of the samples were determined by 4 different test systems namely β-carotene/linoleic acid, 1,1-diphenyl-2-picrylhydrazyl (DPPH), reducing power, and chelating effect. In all systems, essential oil showed the weakest activity profile. On the other hand, ethyl acetate and water extracts exhibited excellent antioxidant activities. As well as the antioxidant activities of the extracts, they were evaluated in terms of their total phenolic and flavonoid contents. In parallel to the experiments, ethyl acetate and water extracts were found to be rich-in these phytochemicals. © KoSFoST and Springer 2010.Item Phenolic composition, antioxidant and enzyme inhibitory activities of acetone, methanol and water extracts of Clinopodium vulgare L. subsp. vulgare L.(Elsevier, 2015) Sarikurkcu C.; Ozer M.S.; Tepe B.; Dilek E.; Ceylan O.The aim of this study is to evaluate the antioxidant and enzyme inhibitory activities of acetone, methanol and water extracts of Clinopodium vulgare L. subsp. vulgare L. as well as its phytochemical composition. Methanol extract was found rich in of phenolic compounds (44.42. mg GAEs/g extract) whereas the highest flavonoid content was determined in the water extract (40.20. mg REs/g extract). Methanol extract was also found rich in protocatechuic acid, (+)-catechin, chlorogenic acid, caffeic acid, ferulic acid, rosmarinic acid and apigenin. Data obtained from the phosphomolybdenum assay was found in correlation with those obtained from total phenolic assay. Methanol extract exhibited the highest activity (374.86. mmol TEs/g extract). In the case of chelating effect assay, acetone extract exhibited the highest activity. As observed in many previously reported studies, water extract exhibited the highest DPPH free radical scavenging activity (81.72. mg TEs/g extract). ABTS cation scavenging assay was resulted in the superiority of methanol extract (51.45. mg TEs/g extract). It also showed the strongest reducing power in CUPRAC and FRAP assays. Acetone extract exhibited remarkable inhibitory activity on acetylcholinesterase, butyrylcholinesterase and tyrosinase, while the highest α-amylase and α-glucosidase inhibitory activities were exhibited by methanol and water extracts. Total amounts of unsaturated fatty acids were determined as 51.15%. C18:1 ω9, C18:2 ω6 and C18:3 ω3 were determined in considerable quantities (23.93, 6.18 and 5.78%, respectively). © 2015 Elsevier B.V.Item Phenolic composition, antioxidant and enzyme inhibitory activities of ethanol and water extracts of: Chenopodium botrys(Royal Society of Chemistry, 2016) Ozer M.S.; Sarikurkcu C.; Tepe B.In this study, we aimed to evaluate the phenolic composition, antioxidant, and enzyme inhibitory activities of ethanol and water extracts of Chenopodium botrys L. In the ethanol extract, the amounts of flavonoids, saponins, and condensed tannins were found to be higher than those of the water extract (4.54 mg of rutin equivalent (RE) per g of dry plant, 25.45 mg of quillaja equivalent (QAE) per g of dry plant, and 59.20 mg of catechin equivalent (CE) per g of dry plant, respectively). On the other hand, a total phenolic assay showed a superiority of the water extract (3.85 mg of gallic acid equivalent (GAE) per g of dry plant). The extracts were also subjected to screening for the quantification of selected compounds. Among the compounds, benzoic acid was found to be the most abundant one in the extracts (59.93 and 2974.24 μg per g of dry plant, respectively). In general, antioxidant activity assays showed the superiority of the water extract. C. botrys extracts were also evaluated for their inhibitory activities on acetylcholinesterase (AChE), butyrylcholinesterase (BChE), tyrosinase, α-amylase, and α-glucosidase. The water extract exhibited the highest inhibitory activity on AChE, tyrosinase, α-amylase, and α-glucosidase (113.69 μg of galantine equivalent (GALAE) per g of dry plant, 165.56 μg of kojic acid equivalent (KAE) per g of dry plant, 7.16 mg of acarbose equivalent (ACE) per g of dry plant, and 6.47 mg of ACE per g of dry plant, respectively). On the other hand, BChE inhibitory activity of the ethanol extract was found to be higher than that of the water extract (60.90 μg of GALAE per g of dry plant). According to the results of the antioxidant and enzyme inhibitory activity assays, C. botrys may have the potential to prevent diseases associated with oxidative stress and to prevent AD, pigmentation diseases, hyperglycaemia and its associated complications. © The Royal Society of Chemistry 2016.Item Fatty acid composition, enzyme inhibitory, and antioxidant activities of the ethanol extracts of selected wild edible plants consumed as vegetables in the Aegean region of Turkey(Taylor and Francis Inc., 2017) Sarikurkcu C.; Targan S.; Ozer M.S.; Tepe B.The aim of this study was to evaluate the fatty acid composition, enzyme inhibitory, and antioxidant activities of the ethanol extracts of selected wild edible plants consumed as vegetable in the Aegean region of Turkey. In general, Mentha piperita L., Rumex patientia L., and R. acetosella L. exhibited quite strong antioxidant activities in the majority of test systems, whereas Urtica dioica L. and Eruca sativa Mill. show quite weak antioxidant activities. Enzyme inhibitory activities of the plants were found quite different than those of their antioxidant activities. Cardaria draba (L.) Desv., E. sativa, R. patientia, and E. cicutarium (L.) L’Hér. showed the highest inhibitory activities on acetylcholinesterase, butyrylcholinesterase, α-amylase, and α-glucosidase, respectively. U. dioica also showed a promising inhibitory activity on these enzymes. In parallel to the experiments, total phenolic, flavonoid, flavonol, and saponin contents of the extracts were also determined. According to the results of these assays, M. piperita had the highest amounts of phenolics, flavonols, and saponins (162.36 mg gallic acid equivalents/g extract, 3.52 mg CEs/g extract and 761.54 mg QAEs/g extract, respectively). Opopanax hispidus (Friv.) Griseb. and Lepidium sativum L. were found to be rich in flavonoid compounds (121.18 and 104.21 mg Res/g extract, respectively). In general, a strong correlation was determined between the phytochemical profile and antioxidant activity of the plant species. © 2017 Taylor & Francis Group, LLC.Item A comprehensive study on chemical composition, antioxidant and enzyme inhibition activities of the essential oils of Chenopodium botrys collected from three different parts of Turkey(Elsevier B.V., 2017) Ozer M.S.; Sarikurkcu C.; Ceylan O.; Akdeniz I.; Tepe B.In this study, we aimed to evaluate the chemical composition of the essential oil of Chenopodium botrys L. collected from three different parts of Turkey. Additionally, we analyzed the antioxidant activities of the oil samples by using free radical scavenging, phosphomolybdenum, ferrous ion chelating, and reducing power assays as well as their inhibitory activities on acetylcholinesterase (AChE), butyrylcholinesterase (BChE), and tyrosinase. According to the results of GC-FID and GC–MS analyses, twenty-seven, twenty-four, and sixteen compounds were identified representing 94.45%, 96.96%, and 94.41% of the oils, respectively. In Afyonkarahisar and Isparta samples, ledol (25.11% and 22.73%), elemol (15.25% and 24.86%), and germacrene D-4-ol (14.83% and 11.27%) were determined as the major compounds, whereas ledol (31.83%), elemol (23.70%), and eudesm-7(11)-en-4-ol (8.94%) were found as the main compounds of Konya sample. The oil of Isparta sample showed the maximum radical scavenging activity in all test systems, except superoxide anion radical scavenging assay. Phosphomolybdenum, ferrous ion chelating, and reducing power assays were resulted in the superiority of Afyonkarahisar sample. In AChE and tyrosinase inhibition assays, the essential oil of C. botrys collected from Konya showed the maximum activity (0.87 mg GALAEs/g oil and 0.82 mg KAEs/g oil, respectively). On the other hand, BChE inhibition assay was resulted in the superiority of Afyonkarahisar sample (1.02 mg GALAEs/g oil). In order to determine the contribution of oil components to the biological activity, correlation coefficients between the compounds and assays were also presented. © 2017Item Onosma heterophyllum: Phenolic composition, enzyme inhibitory and antioxidant activities(Elsevier B.V., 2018) Ozer M.S.; Kirkan B.; Sarikurkcu C.; Cengiz M.; Ceylan O.; Atılgan N.; Tepe B.Onosma species have frequently been used for their colouring and dyeing properties in foods and medicinal preparations. The antioxidant and enzyme inhibitory activities of the ethyl acetate, methanol and water extracts of Onosma heterophyllum (Griseb.) are described. Phytochemical compositions of these extracts were also determined. The water extract showed not only remarkable antioxidant activity in all assays but also considerable inhibitory activity on tyrosinase and α-glucosidase (112.44 μmol KAEs/g dry plant and 984.36 μmol ACEs/g dry plant, respectively). The methanol extract exhibited the highest inhibitory activity on acetylcholinesterase (AChE) and α-amylase (79.18 μmol GALAEs/g dry plant and 10.42 μmol ACEs/g dry plant, respectively). Chromatographic analyses revealed that the water extract was found to be rich in phenolic and flavonoid contents. On the basis of the correlation coefficients calculated separately for all experimental parameter pairs, protocatechuic acid, p-hydroxybenzoic acid, syringic acid, p-coumaric acid and luteolin were found to be highly in correlation with the antioxidant and enzyme inhibitory activities. This study demonstrates that O. heterophyllum, contained in food preparations with various purposes for many years, could be used for the treatment of diabetes as well as its skin whitening effect. © 2017 Elsevier B.V.Item Chemical characterization and biological activity of Onosma gigantea extracts(Elsevier B.V., 2018) Sarikurkcu C.; Kirkan B.; Ozer M.S.; Ceylan O.; Atilgan N.; Cengiz M.; Tepe B.Onosma species have traditionally been used as laxative and anthelmintic agents as well as their uses in eye, blood diseases, bronchitis, abdominal pain, strangury, thirst, itch, leucoderma, fever, wounds, burns, piles, and urinary calculi. This study examines the investigation of biological activities of ethyl acetate, methanolic, and aqueous extracts from Onosma gigantea Lam. The extracts were evaluated for the antioxidant and enzyme inhibitory activities. Phenolic compounds in the extracts were also detected by RP-HPLC-DAD. The aqueous extract showed remarkable antioxidant activity in phosphomolybdenum [134.31 μmol trolox equivalents (TEs)/g air dry matter (adm)], chelating effect [32.97 μmol ethylenediaminetetraacetic acid (disodium salt) equivalents (EDTAEs)/g adm], radical scavenging [on DPPH (32.14 μmol TEs/g adm) and ABTS (58.68 μmol TEs/g adm)], and reducing power [CUPRAC (50.23 μmol TEs/g adm) and FRAP (40.96 μmol TEs/g adm)] assays. The aqueous extract also exhibited considerable inhibitory activity of tyrosinase (10.48 μmol kojic acid equivalents/g adm) and α-glucosidase [1320.53 μmol acarbose equivalents (ACEs)/g adm]. It has been determined that the methanolic extract showed significant AChE (31.57 μmol galanthamine equivalents (GALAEs)/g adm) and α-amylase (6.75 μmol ACEs/g adm) inhibitory activity. The ethyl acetate, which contains low polarity compounds, showed the highest BChE inhibitory activity (6.87 μmol GALAEs/g adm). In general, it is found that there is a positive correlation between the phytochemical contents of the extracts and their biological activities. The results indicate that O. gigantea extracts could be considered as a novel source of bioactive agents with functional connections. © 2018 Elsevier B.V.Item Can the stalks of Papaver somniferum L. be an alternative source of bioactive components?(Elsevier B.V., 2018) Kirkan B.; Ozer M.S.; Sarikurkcu C.; Copuroglu M.; Cengiz M.; Tepe B.Alternative raw materials for designing novel products are gaining interest in the scientific area. The aim of this study is to investigate the antioxidant and enzyme inhibitory activities of the extracts obtained from Papaver somniferum L. stalks as well as the determination of chemical composition. Antioxidant capacity was tested by using different chemical methods including radical scavenging, reductive effect, phosphomolybdenum and metal chelating assays. Enzyme inhibitory effect was investigated against cholinesterase, tyrosinase, α-amylase and α-glucosidase. To detect chemical composition, phenolic profile was determined by high performance liquid chromatography (HPLC) as well as total contents of the phytochemicals. The aqueous extract was found to contain high amount of phenolics and flavonoids [9.87 μmol gallic acid equivalents (GAEs)/g dry plant (dp) and 0.09 μmol rutin equivalents (REs)/g dp, respectively]. The methanol and aqueous extracts were also found to contain considerable amounts of (−)-epicatechin and syringic acid. Antioxidant activity tests were resulted in the superiority of the methanol extract. The extracts did not show inhibitory activity on cholinesterases and tyrosinase. Inhibitory activity of the aqueous extract on α-amylase and α-glucosidase were found to be 9.85 and 78.64 μmol acarbose equivalents (ACEs)/g dp, respectively. As a result, P. somniferum stalks, one of the major by-products of poppy cultivation, can be used as the alternative source of antioxidant and enzyme inhibitory compounds in food and medical industries. © 2018 Elsevier B.V.Item Essential oil composition and antioxidant activity of endemic Marrubium parviflorum subsp. oligodon(Elsevier B.V., 2018) Sarikurkcu C.; Ozer M.S.; Calli N.; Popović-Djordjević J.In this study, chemical composition and antioxidant activity of the essential oil and solvent extracts (hexane, dichloromethane, ethyl acetate, methanol and water) obtained from aerial parts of the endemic plant Marrubium parviflorum subsp. oligodon collected from Afyonkarahisar province in Turkey were examined. The antioxidant ability of solvent extracts and essential oil was evaluated using various methods (β-carotene-linoleic acid, 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging, and reducing power assays) and the content of total phenolics and flavonoids were determined. In the essential oil, thirty-one compounds were identified by GC/MS analysis. The major components were (Z,Z)-farnesyl acetone (19.28%), caryophyllene oxide (15.85%) and pulegone (7.15%). In all assays, water extract showed the strongest antioxidant properties due to the highest content of total phenolics. The significantly high correlations were observed between the content of total phenolics and DPPH radical (0.894) and reducing power (0.983) assays. Methanol extract was the richest in total flavonoids. The present results support the traditional and possible use of the essential oil and extracts from M. parviflorum subsp. oligodon in food, pharmaceutical, and cosmetic industries. © 2018 Elsevier B.V.Item Phenolic profile, antioxidant and enzyme inhibitory potential of Onosma tauricum var. tauricum(Elsevier B.V., 2018) Kirkan B.; Sarikurkcu C.; Ozer M.S.; Cengiz M.; Atılgan N.; Ceylan O.; Tepe B.This study focused on phytochemical characterization and biological evaluation, both antioxidant and enzymatic inhibition, of ethyl acetate (OTT-EtOAc), methanol (OTT-MeOH), and water (OTT-W) extracts from Onosma tauricum var. tauricum aerial parts. The OTT-W extract was found to be the richest one in terms of its phenolic and flavonoid contents. Amounts of the phenolic and flavonoid compounds were determined as 40.88 μmol GAEs/g and 7.40 μmol REs/g dry plant (dp), respectively. The OTT-MeOH and OTT-W extracts were also found to contain significant amounts of chlorogenic acid, rosmarinic acid, p-hydroxybenzoic acid, caffeic acid, rutin, p-coumaric acid, trans-cinnamic acid, luteolin, and apigenin. The OTT-W extract showed remarkable antioxidant activity in phosphomolybdenum, ferrous ion chelating, reducing power, and radical scavenging assays. The OTT-MeOH extract exhibited inhibitory activity on acetylcholinesterase (AChE) (54.62 μmol GALAEs/g dp), while the extracts remained almost inactive on butyrylcholinesterase (BChE). The OTT-W extract also exhibited inhibitory activity on tyrosinase (90.66 μmol KAEs/g dp) and α-glucosidase (2258.87 μmol ACEs/g dp). The results suggest that especially the OTT-MeOH and OTT-W extracts can be used as a source of alternative natural products in the treatment of diseases caused by the enzymes evaluated here. © 2018 Elsevier B.V.Item Calamintha incana: Essential oil composition and biological activity(Elsevier B.V., 2019) Popović-Djordjević J.; Cengiz M.; Ozer M.S.; Sarikurkcu C.The chemical composition of the essential oils (EO) isolated aerial parts of Calamintha incana (Sm.) Boiss. from Turkey was characterized by GC-FID and GC–MS analysis. The oxygenated monoterpenes trans-piperitone oxide (41.37%), piperitenone oxide (34.47%), piperitenone (6.67%), and monoterpene phenol thymol (3.37%) were found to be the major constituents of the essential oils of C. incana. The results of the antioxidant activity in phosphomolybdenum, radical scavenging (DPPH and ABTS) and reducing power activity (CUPRAC and FRAP) as well as metal chelating effects (ferrous ion chelating) showed that EO was the most potent in ABTS (129.58 ± 2.21 mg TEs/g oil) and CUPRAC and FRAP (51.14 ± 0.05 and 53.63 ± 0.10 mg TEs/g, respectively) assays. In enzymes inhibitory activity assays of EO, the best result was achieved for tyrosinase (2.10 ± 0.30 mg KAEs/g oil). The results suggest that EO might be considered as a potential source of bioactive agents to be used in food and pharmacological industries. © 2018 Elsevier B.V.Item LC–ESI–MS/MS characterization of phytochemical and enzyme inhibitory effects of different solvent extract of Symphytum anatolicum(Elsevier B.V., 2019) Sarikurkcu C.; Ozer M.S.; Tlili N.Symphytum anatolicum Boiss., is a species belonging to the Boraginaceae family and have been used for its curative effects. This work investigated, for the first time, the bioactive compounds, the antioxidant activities and the enzyme inhibitory effects of Symphytum anatolicum roots extracts using three solvents (methanol, water and ethyl acetate). The LC–ESI–MS/MS was used to identify the individual bioactive compounds. Twenty-three biomolecules were identified in the extracts and rosmarinic acid, verbascoside, caffeic acid, chlorogenic acid and vanillin were the main identified with varied levels depending on the solvent used. Using six different assays, all extracts exhibited important antioxidant activities. Results showed also that the methanol extract exerted better tyrosinase inhibitory activities while ethyl acetate extract showed the best α-amylase inhibition. The obtained results highlighted the importance of S. anatolicum as a natural resource of bioactive compounds and encourage the use of this unexploited species for food additives, pharmaceutical industries, and skincare products. © 2019 Elsevier B.V.Item Datura innoxia and Dipsacus laciniatus: Biological activity and phenolic composition(Elsevier Ltd, 2019) Benabderrahim M.A.; Sarikurkcu C.; Elfalleh W.; Ozer M.S.In the present study, we investigated the phenolic composition of the methanol extract from the aboveground of two plants of Turkish flora; Datura innoxia and Dipsacus laciniatus. In addition, the antioxidant (phosphomolybdenum, CUPRAC, FRAP, DPPH, ABTS)and enzyme inhibitory activities (α-amylase and tyrosinase), and total phenolic and flavonoids contents were determined in these plant extracts. The results showed high significant differences among plants (p ≤ 0.05)for the antioxidant capacities measured with the different methods, the enzyme inhibitory activities, and the all identified phenolic compounds except for hyperoside. From a total of 23 identified phenolic compounds, 19 were found in both plants. The main flavonoids identified were (+)-catechin and (−)-epicatechin and hyperoside. (+)-Catechin and (−)-epicatechin showed very high concentrations in D. innoxia (12937.39 ± 108.86 and 24147.64 ± 2512.35 μg/g of dry plant, respectively)and in D. laciniatus (4947.99 ± 14.18 and 13171.30 ± 2410.76 μg/g of dry plant, respectively). Hyperoside had interesting contents with comparable values (115.11 ± 16.20 in D. innoxia, and 110.77 ± 16.32 μg/g of dry plant in D. laciniatus). The major phenolic acid was chlorogenic acid especially in D. laciniatus (12124.22 ± 598.13 μg/g of dry plant). These compounds were correlated to the high antioxidant and enzyme inhibitory activities for both species and confirm their medicinal traditional uses. Hence, further screening of bioactive compounds in different organs such as flowers and roots of these plants is crucial for the discovering of new source of natural antioxidants and enzyme inhibitors. © 2019 Elsevier LtdItem LC-MS/MS profiles and interrelationships between the enzyme inhibition activity, total phenolic content and antioxidant potential of Micromeria nervosa extracts(Elsevier Ltd, 2020) Sarikurkcu C.; Andrade J.C.; Ozer M.S.; de Lima Silva J.M.F.; Ceylan O.; de Sousa E.O.; Coutinho H.D.M.The objective of this study was to quantify the phenolic compounds and to evaluate and compare the biological activities of the ethyl acetate (EtOAc), methanolic (MeOH) and aqueous extracts from the Micromeria nervosa aerial parts, based on their antioxidant activity and enzymatic inhibition. Total phenolic and flavonoid contents were calculated and individual compo3unds were detected using LC-ESI-MS/MS. The antioxidant activity was determined using six different assays while enzymatic activity was determined by α-amylase and tyrosinase enzyme inhibition. The main phenolic constituents detected in the extracts were rosmarinic acid. In the antioxidant assays the aqueous extract was shown to be more efficient than the others. The EtOAc and MeOH extracts presented higher inhibitory activity with respect to α-amylase and tyrosinase. Regardless of the solvent, the results suggest M. nervosa aerial extracts present a biological potential due to their antioxidant activity and enzymatic inhibition. © 2020 Elsevier LtdItem Valeriana dioscoridis aerial parts' extracts - A new source of phytochemicals with antioxidant and enzyme inhibitory activities(Elsevier B.V., 2020) Sarikurkcu C.; Jeszka-Skowron M.; Ozer M.S.Valeriana root extracts are used in herbal medicine for treating sleep disorders. There is a lack of information of phytochemical composition of Valeriana dioscoridis aerial parts’ extracts. The aim of the study was to measure antioxidant activity, determine the phenolic compounds from different groups such as phenolic acids and polyphenolic compounds: verbascoside or eriodictyol, and enzyme inhibitory activities in ethyl acetate, methanol and water extracts. The methanol extract showed the highest antioxidant activity almost in all assays (excluding ferrous ion chelating activity). Moreover, the concentrations of the determined phytochemicals mainly chlorogenic acid content (21.4 ± 0.7 mg/g), hesperidin (2.10 ± 0.05 mg/g) and protocatechuic acid (0.94 ± 0.02 mg/g) were the greatest for this extract. It was also the richest in all determined compounds – 21 phytochemicals were identified and water extract was the second most abundant in analytes (20 phytochemicals). The predominant compounds in water extract were the following: chlorogenic acid (20.3 ± 0.12 mg/g), protocatechuic acid (0.83 ± 0.02 mg/g) and caffeic acid (0.72 ± 0.01 mg/g). Protocatechuic acid was prevailing in ethyl acetate extract (0.59 ± 0.01 mg/g). In addition, in this extract the highest inhibitory activity of α-amylase was found and the highest amount of verbascoside was determined in comparison to other extracts (0.53 ± 0.01 mg/g). The tyrosinase inhibitory effect especially of methanol extract was also shown. Pearson correlation confirmed that the strong biological activity of methanol extract from V. dioscoridis resulted mainly from its high content of chlorogenic acid. © 2020 Elsevier B.V.Item Comparison of the Influence of the Solvent on the Extraction of the Bioactive Compounds from Marrubium lutescens Using Liquid Chromatography–Electrospray Ionization Tandem Mass Spectrometry (LC-ESI-MS/MS)(Taylor and Francis Inc., 2020) Sarikurkcu C.; Ozer M.S.; Tlili N.To our knowledge, this is the first study on the influence of water, ethyl acetate and methanol as the extraction solvent upon the bioactive compound composition, antioxidant capacities and enzyme inhibitory activities of Marrubium lutescens isolates. The contents of the total phenolic compounds varied between 9.94 and 54.80 mg gallic acid equivalent/g extract and the level of total flavonoids were between 4.45 and 27.20 mg quercetin equivalent/g extract. Twenty-four compounds were identified using liquid chromatography–electrospray ionization tandem mass spectrometry (LC-ESI-MS/MS). Rosmarinic acid, luteolin 7-glucoside, chlorogenic acid, caffeic acid and hyperoside were the primary compounds present for all of the used solvents. The most compounds (23) were detected in the methanol extract. Six antioxidant assays revealed that M. lutescens extracts showed interesting antioxidant activities with a significant variation between the extracts. The results revealed that the highest tyrosinase and α-amylase inhibitory activities was detected in the ethyl acetate extract. This work confirmed that the nature of solvent influenced the levels and the types of the extracted biomolecules. Moreover, the obtained results suggest that M. lutescens may be a source of bioantioxidants for industrial additives. © 2020, © 2020 Taylor & Francis Group, LLC.Item Enzyme and biological activities of the water extracts from the plants aesculus hippocastanum, olea europaea and hypericum perforatum that are used as folk remedies in Turkey(MDPI AG, 2020) Sarikurkcu C.; Locatelli M.; Tartaglia A.; Ferrone V.; Juszczak A.M.; Ozer M.S.; Tepe B.; Tomczyk M.Phenolic compounds are secondary metabolites that are found ubiquitously in plants, fruits, and vegetables. Many studies have shown that regular consumption of these compounds could have a positive effect on our health. The aim of this study was to compare the phytochemical contents of the water extracts from three different plants used as folk remedies in Turkey: Aesculus hippocastanum, Olea europaea, and Hypericum perforatum. A liquid chromatography-electrospray tandem mass spectrometry (LC-ESI-MS/MS) analysis was performed to explore the phenolic profiles. The biological activities of these extracts were also evaluated in terms of their antioxidant activities (2,2-diphenyl-1-picrylhydrazyl DPPH, 2,2'-azino-bis-(3-ethylbenzothiazoline-6-sulfonic acid ABTS, Ferric Reducing Antioxidant Power Assay FRAP, cupric ion reducing antioxidant capacity CUPRAC, β-carotene, phosphomolybdenum, and metal chelating) and enzyme inhibitory properties (against acetylcholinesterase, butyrylcholinesterase, and tyrosinase). The aqueous extract of H. perforatum showed the highest levels of total phenolic, flavonoid, and saponin contents. Protocatechuic acid, vanillic acid, verbascoside, hesperidin, hyperoside, apigenin 7-hexosides, and quercetin were the most common compounds found in this species. The results confirm that A. hippocastanum, O. europaea, and H. perforatum represent a potential source of natural-derived molecules with positive properties that could be used as valid starting point for new food supplements, and drugs in the pharmaceutical, cosmetic, and food industries. © 2020 by the authors.Item Nutraceutical extracts from some endemic Onosma (O. circinnata, O. bornmuelleri, and O. angustissima) species: LC–ESI-MS/MS–based polyphenol profile, antioxidant and enzyme inhibition activities(John Wiley and Sons Inc, 2021) Sarikurkcu C.; Sahinler S.S.; Ozer M.S.; Sihoglu Tepe A.This study aimed to determine the chemical composition of methanol extracts from Onosma circinnata, Onosma bornmuelleri, and Onosma angustissima and to investigate their antioxidant and enzyme inhibitory activities. Spectrophotometric analysis showed that the extracts were found to be rich in chlorogenic acid, luteolin 7-glucoside, rosmarinic acid, and apigenin 7-glucoside. While O. bornmuelleri showed the highest activity in DPPH, ABTS, and FRAP tests, O. circinnata was more effective in CUPRAC, phosphomolybdenum, and ferrous ion chelating tests. While O. angustissima showed significant inhibitory activities on AChE, BChE, and tyrosinase, O. bornmuelleri and O. circinnata showed the highest inhibitory activities on α-amylase and α-glucosidase. It was concluded that O. circinnata and O. bornmuelleri are effective antioxidant agents and O. angustissima can be considered as an alternative agent in the medical and cosmetic industries due to its ChE and tyrosinase inhibitory activities. Novelty impact statement: Biological activities of Onosma species were brought to the literature for the first time with this study. O. circinnata showed remarkable antioxidant activity. O. angustissima exhibited the highest AChE, BChE and tyrosinase inhibitory activity. © 2021 Wiley Periodicals LLC.