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Öğe Adsorption of cellulase on poly(2-hydroxyethyl methacrylate) cryogels containing phenylalanine(Tubitak Scientific & Technological Research Council Turkey, 2016) Yavuz, Murat; Cakir, Oguz; Baysal, ZubeydeThe aim of this study was to prepare a supermacroporous cryogel that can be used for the adsorption of cellulase. The macroporous cryogel of poly(2-hydroxyethyl methacrylate-N-methacryloyl-L-phenylalanine) [p(HEMA-MAPA)] was prepared by copolymerization of 2-hydroxyethyl methacrylate (HEMA) with a functional monomer of N-methacryloyl-L-phenylalanine (MAPA). The cryogel was characterized by scanning electron microscopy, Fourier transform infrared spectroscopy, and swelling tests. The effects of several parameters such as medium pH, temperature, ionic strength, and flow rate on cellulase adsorption were also investigated. Maximum cellulase adsorption was observed at 25 degrees C and pH 4.0. Furthermore, adsorbed cellulase was desorbed from the cryogel by using 1.0 M NaCl. The p(HEMA-MAPA) cryogel could be used many times without the cellulase adsorption capacity decreasing significantly.Öğe A comprehensive LC-MS/MS method validation for the quantitative investigation of 37 fingerprint phytochemicals in Achillea species: A detailed examination of A. coarctata and A. monocephala(Elsevier Science Bv, 2018) Yilmaz, Mustafa Abdullah; Ertas, Abdulselam; Yener, Ismail; Akdeniz, Mehmet; Cakir, Oguz; Altun, Muhammed; Demirtas, IbrahimThe current study aims to optimize and validate a comprehensive LC-MS/MS method for the quantification of 37 phytochemicals (15 phenolic acids, 17 flavonoids, 3 non-phenolic organic acids, 1 phenolic aldehyde and 1 benzopyrene) in Achillea species. Though Achillea species were chosen as real life samples, the current method is applicable to a wide range of plant species. The developed method was fully validated in terms of linearity, accuracy (recovery), inter-day and intra-day precision (repeatability), limits of detection and quantification (LOD/LOQ) and relative standard uncertainty (U% at 95% confidence level (k = 2)). Reversed-phase ultrahigh performance liquid chromatography was optimized to achive optimum separation for 37 phytochemical compounds and to overcome the suppression effects. MS detection was performed using a triple quadrupole mass spectrometer and negative or positive ionization modes were optimized for each analyte. Multiple reaction monitoring (MRM) was used to quantify the analytes, related molecular ions and transition ions were optimized. Phytochemical screening of ethanol and methanol-chloroform extracts of root and aerial parts of A. coarctata and A. monocephala were performed by using the developed and validated LC-MS/MS method. Root and aerial parts of both species have considerable amounts of certain phenolic-nonphenolic acids (quinic, malic, fumaric, chlorogenic and vanillic acids) and flavonoids (rutin, hesperidin, isoquercitrin, apigetrin, luteolin, apigenin). Additionally, total phenolic and flavonoid amounts, antioxidant (DPPH free radical scavenging assay, ABTS radical cation decolorization assay, beta-carotene lipid peroxidation test system and CUPRAC cupper reduction capacity methods), anticholinesterase, tyrosinase, urease inhibition and cytotoxic activities (on HeLa (Human Cervical Carcinoma Cell Line) of A. coarctata and A. monocephala were also investigated. It has been determined that the studied Achillea species, that are rich in total phenolic-flavonoid and chlorogenic acid contents, have high antioxidant and cytotoxic potential at the same time. According to the results of LC-MS/MS, antioxidant and cytotoxic activity studies, after detailed chemical investigation and toxicity studies on these species, A. coarctata and A. monocephala may be promoted as promising sources of natural agents and used for the development of nutraceuticals or functional food ingredients in future. (C) 2018 Elsevier B.V. All rights reserved.Öğe A fast, accurate and comprehensive LC-MS/MS method validation for the sensitive quantification of water-soluble vitamins in walnut, almond, hazelnut and pistachio fruits(Elsevier, 2023) Yilmaz, Mustafa Abdullah; Cakir, Oguz; Yener, IsmailEvaluating nutritional values of food products such as nuts has been of great importance nowadays. In the current study, development and validation of a robust and fast LC-MS/MS method was carried out for simultaneous determination of pantothenic acid (B5), riboflavin (B2), biotin (B7), thiamine (B1), cyano-cobalamine (B12), nicotinamide (B3), nicotinic acid (B3), pyridoxine (B6) and folic acid (B9) in walnut, almond, hazelnut and pistachio samples from Turkey. Isotope labeled vitamin standards were used to compensate the sensitivity losses and increase the degree of precision. The validation parameters of the developed analytical method were accuracy (recovery), linearity, limit of quantification (LOQ), intra-day and inter-day precision (repeatability), relative standard uncertainty (U% at 95% confidence level (k 1/4 2)), and limit of detection (LOD). Chromatographic parameters were optimized to have optimum separation of nine water soluble vitamins (WSVs) and MS detection was performed using a tandem mass spec-trometer. Linearity of the established LC-MS/MS method was in the range of 25-1000 ng/mL for the studied vitamins. The coefficients of determination for the vitamins were between 0.9973 and 0.9999. LOD/LOQ values of the analytes were 10.48/12.54, 13.08/19.59, 5.77/7.70, 12.48/17.71, 12.38/14.90, 6.55/ 10.08, 8.08/9.81, 13.03/16.38, 13.08/19.59 for B1, B2, nicotinamide (B3), nicotinic acid (B3), B5, B6, B7, B9 and B12, respectively.(c) 2023 Elsevier B.V. All rights reserved.Öğe HPLC-MS/MS Profile, Analgesic and Anti-inflammatory Activities of Lawsonia inermis Seed Fractions(Faculty of Pharmacy, University of Benin, 2024) Moutawalli, Amina; Benkhouili, Fatima Zahra; El-Guourrami, Otman; El-Otmani, Najlae; El Ouazzani, Fadoua; Zengin, Gokhan; Cakir, OguzPain and inflammation are common symptoms present in many medical conditions, typically managed with analgesic and anti-inflammatory medications. However, these medications, whether targeting peripheral or central pathways, are often associated with adverse side effects. This study aimed to identify the constituents of Lawsonia inermis seed fractions, and evaluate the analgesic, and anti-inflammatory activities of these fractions. Chemical constituents of the fractions were characterized using high-performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS). The analgesic properties were evaluated using the acetic acid-induced writhing and tail immersion tests, while anti-inflammatory activity was assessed via the carrageenan-induced paw edema model in mice. A total of 29 compounds were identified, with the ethanol fraction exhibiting the highest concentration of the constituents, amounting to 93.89 mg/g fraction. Major compounds detected in the ethanol fraction included gallic acid, catechin, tannic acid, vanillin, epicatechin gallate, isoquercitrin, and ellagic acid. The study revealed that the ethanol fraction demonstrated a notable peripheral analgesic effect, achieving 34.75% inhibition at a dose of 250 mg/kg in mice, while the aqueous fraction showed substantial central analgesic activity in rats at 500 mg/kg throughout the experimental period. Additionally, at a dose of 400 mg/kg, the ethanol fraction resulted in a 74.05% inhibition of inflammation in mice, outperforming indomethacin, which achieved a 58.09% inhibition at 10 mg/kg after 4 h. These findings present novel evidence that the fractions of L. inermis seed exhibit significant analgesic and anti-inflammatory activities, supporting the traditional medicinal use of this plant for the management of conditions involving pain and inflammation. © 2024 Moutawalli et al. © 2024 the authors.Öğe Novel QCM and SPR sensors based on molecular imprinting for highly sensitive and selective detection of 2,4-dichlorophenoxyacetic acid in apple samples(Elsevier, 2019) Cakir, Oguz; Bakhshpour, Monireh; Yilmaz, Fatma; Baysal, ZubeydeThis study aims to develop molecularly imprinted based quartz crystal microbalance (QCM) and surface plasmon resonance (SPR) sensors for highly sensitive and selective detection of 2,4-dichlorophenoxyacetic acid (2,4-D) and to determine their accuracy and precision by liquid chromatography-tandem mass spectrometry (LC-MS/MS) as a reference technique. Here, we synthesized non-imprinted (NIP) and 2,4-D-imprinted (MIP) [ethylene glycol dimetacrylate-N-metacryloyl-(L)-tryptophan methyl ester-p(EGDMA-MATrp)] polymeric nanofilms by using molecular imprinting technique. MIP and NIP nanofilms were characterized by fourier transform infrared spectroscopy attenuated total reflectance (FTIR-ATR), atomic force microscope (AFM), contact angle and ellipsometer measurements. The molecular imprinting procedures were successfully carried out and it was found that the prepared polymeric surfaces were highly desirable for sensitive recognition by QCM and SPR sensors. Competitive experiments for the sensors revealed that MW nanofilms were found to show more sensitivity and selectivity than NIP ones. The sensor responses have a good linear relationship with 2,4-D concentrations in the range of 0.23-8.0 nM with a limit of detection at 20.17 ng/L for QCM and 24.57 ng/L for SPR sensors. In conclusion, both QCM and SPR sensor systems showed good accuracy and precision, with recovery percentages between 90 and 92% and 87-93%, respectively. Furthermore, they have a fast response time, reusability, high selectivity and sensitivity and low limit of detection.Öğe Pesticide analysis with molecularly imprinted nanofilms using surface plasmon resonance sensor and LC-MS/MS: Comparative study for environmental water samples(Elsevier Science Sa, 2019) Cakir, Oguz; Baysal, ZubeydeSPR sensor chip nanofilms were prepared using a molecular imprinting method. Characterization of nanofilms was achieved by fourier-transform infrared spectroscopy attenuated total reflectance (FTIR-ATR), contact angle, atomic force microscope, and ellipsometer. Kinetic and affinity binding of pesticides were investigated by binding pesticide imprinted and nonimprinted sensor chips to the SPR sensor. Comparative adsorption experiments for SPR sensors were performed to display the selectivity of pesticide imprinted nanofilms. Analysis of the SPR sensors revealed that imprinted nanofilms showed more sensitivity and selectivity than the nonimprinted ones for pesticide determination. Exact masses of molecular and fragmentation ions of pesticides were determined by liquid chromatography ion trap time-of-flight mass spectroscopy (LC/MS-IT-TOF). According to these exact masses and fragmentation ions, an LC-MS/MS method was prepared and validated for qualitative and quantitative analysis of the studied pesticides. The limit of detection values of dimethoate and carbofuran were found to be 16.92 ng L-1 and 20.47 ng L-1 in the LC-MS/MS method and 8.37 ng L-1 and 7.11 ng L-1 in the SPR sensor system, respectively. The accuracy and precision of both methods were determined by comparison of six replicates at three concentrations (50, 250, and 1000 ng L-1), using the same environmental water matrix for each pesticide. SPR sensors showed good accuracy, with recovery percentages between 90 and 95 for both pesticides. The results showed that SPR sensors have higher selectivity and sensitivity, and lower detection limits compared to LC-MS/MS.Öğe Phytochemical composition, antimicrobial, antioxidant, and wound healing activities of Thermopsis turcica(Walter De Gruyter Gmbh, 2024) Akdag, Gulcin; Hazman, Omer; Aksoy, Lacine; Savrik, Mehmet; Buyukben, Ahmet; Yilmaz, Mustafa Abdullah; Cakir, OguzThe antioxidant, antimicrobial, anticarcinogenic, wound healing activities and phenolic substance profile of aqueous extracts prepared using branch, leaf, flower parts and above-ground parts of Thermopsis turcica were determined in the study. The analyses indicate that the total phenolic substance contents and total antioxidant status are higher in the mix, flower, and leaf extracts. The extracts reduced cell viability in HGF cells more than in A549 cells. It shows that the extract has low anticarcinogenic activity in A549 cells. Flower extract had the highest wound closure rate. Quinic acid, cyranoside and luteolin were found in high concentrations in all extracts with LC/ESI-MS/LC analysis. It has been determined that the flower extract of the species is the most critical part showing antioxidant, antimicrobial, cytotoxic and wound healing properties. While the leaf and mix extracts stand out with their antioxidative and antimicrobial properties, the branch extract is effective in wound healing.Öğe Phytochemical profile by LC-MS/MS analysis and evaluation of antioxidant, antidiabetic, anti-Alzheimer, and anticancer activity of Onobrychis argyrea leaf extracts(Elsevier Science Inc, 2024) Yeniceri, Esma; Altay, Ahmet; Koksal, Ekrem; Altin, Sevgi; Taslimi, Parham; Yilmaz, Mustafa Abdullah; Cakir, OguzIntroduction: Studies on different species of Onobrychis, a member of the Fabaceae family, have revealed a number of biological activities with potential applications in alternative medicine. The phytochemical content of the plant Onobrychis argyrea subsp. argyrea and some of the important biological activities linked to its metabolism are quite limited. Therefore, this study was the first to determine the content of secondary metabolites in this species and to elucidate important biological activities related to metabolism. Methods: LC-MS/MS was used for the quantitative analysis of bioactive compounds in the aerial part of O. argyrea extracts. The antioxidant properties of the extracts were assessed based on their ability to scavenge DPPH radicals and reduce iron ions. The anti-diabetic effect of the extracts was tested by the inhibition of alpha-amylase and alpha-glycosidase enzymes, and the anti-Alzheimer's ability was tested by the inhibition of the enzymes AChE and BChE. The cytotoxic effects of the extracts were tested on four different cancer lines, namely A-549, HT-29, MCF-7 and MDA-MB 453 using the XTT assay. The mechanism of the anti-cancer effect was determined by means of flow cytometry analysis on HT-29 cells. Results: Twenty-nine phytochemicals were identified via the LC-MS/MS analysis in the plant extracts. The most abundant phytochemicals in the extracts were quinic acid, isoquercitrin, epicatechin, and routine, respectively. Antioxidant analysis showed that among all extracts, methanol extract (ME) was most effective in scavenging DPPH (IC50: 23.93 +/- 0.96 mu g/mL) and in reducing iron ions (53.24 +/- 2.14 mgTEAC/g). Enzyme activity studies demonstrated that ME is a potent inhibitor of alpha-glycosidase (IC50: 15.06 +/- 0.64 mu g/mL), AChE (IC50: 24.75 +/- 0.76 mu g/mL), and BChE (IC50: 3.36 +/- 0.14 mu g/mL). XTT assay results disclosed the strongest anti-proliferative activity of ME against the human colorectal adenocarcinoma HT-29 cell line with an IC50 value of 33.35 +/- 0.92 mu g/mL. Flow cytometry analysis revealed that ME caused mitochondrial membrane damage in HT-29 cells (**p<0.01) and subsequently induced apoptosis (**p<0.01) by activating the caspase pathway (**p<0.001). Conclusion: O. argyrea, rich in bioactive compounds, showed remarkable antioxidant, antidiabetic, Alzheimer's, and anticancer properties in vitro, demonstrating that this plant contains secondary metabolites that may be potential drug candidates for the treatment of metabolic diseases.Öğe Phytochemical Profiling by UHPLC-ESI-MS/MS, In Vitro Antioxidant, In Vivo Antidiabetic, and Pro-Sexual Effects of Salvia balansae Noë Ex Coss. Flower Extract in Diabetic Male Rats(Wiley-V C H Verlag Gmbh, 2025) Souidi, Wadjila S.; Belhocine, Mansouria; Bouzouina, Mohamed; Yilmaz, Mustafa A.; Feknous, Ines; Cakir, Oguz; Tarhan, AbbasOur study assessed the phytochemical composition and the effects of Salvia balansae flower aqueous extract (FAE) on sexual dysfunction in diabetic rats. Total phenolic and flavonoid content, quantification of phytochemicals by ultrahigh performance liquid chromatography (UHPLC)-electrospray ionization (ESI)-tandem mass spectrometry (MS/MS) method, and in vitro antioxidant capacity of FAE extract were elucidated. For the in vivo study, diabetes was induced by one intraperitoneal injection of streptozotocin (STZ) (40 mg/kg), and treated diabetic rats were given FAE at 200 mg/kg. Rats were subjected to a sexual incentive motivation test (SIM) and a mating behavior test, and then serum testosterone levels and sperm quality were analyzed. Our study indicates that FAE contained a large amount of phenolic compounds and flavonoids, and 13 constituents were quantified; cynaroside (3.8 mg analyte/g extract) was the main compound, followed by rosmarinic acid (3.145 mg analyte/g extract), thus confirming its high antioxidant capacity. FAE treatment significantly reduced blood glucose levels, improved sexual motivation and copulatory behavior, increased testosterone levels, and enhanced sperm quality in diabetic-treated rats compared to diabetic untreated rats. The present work demonstrates the therapeutic potential of S. balansae flowers in enhancing reproductive function in diabetic rats, potentially through its antioxidant, antihyperglycemic, and aphrodisiac properties.Öğe Preparation of a new quartz crystal microbalance sensor based on molecularly imprinted nanofilms for amitrole detection(Biointerface Research Applied Chemistry, 2018) Cakir, Oguz; Yilmaz, Fatma; Baysal, Zubeyde; Denizli, AdilQuartz crystal microbalance (QCM) sensors have been used to detect a variety of biomolecules due to their simplicity, specificity and sensitivity, real-time measurement, low cost and no labeling requirements. A new QCM sensor was prepared by using molecular imprinting method for selective recognition of amitrole. N-metacryloyl-(L)-tryptophan methyl ester (MATrp) was selected as a proper functional monomer and polymerized with ethylene glycol dimethacrylate (EGDMA). Pesticide imprinted poly(ethylene glycol dimetacrylate-N-metacryloyl-(L)-tryptophan methyl ester) [poly(EGDMA-MATrp)] nanofilms were attached to gold surfaces of QCM sensor chips and were characterized by several techniques such as atomic force microscope (AFM), an ellipsometer, FTIR-ATR and contact angle measurements. Kinetic and affinity binding of amitrole was investigated by binding the pesticide imprinted and nonimprinted sensor chips to QCM sensor chips. The imprinted nanofilms were found to show more sensitivity towards the target molecule than the nonimprinted ones. Furthermore, adsorption kinetics were determined by passing pesticide solutions at different concentrations through QCM sensor systems. The most proper model was found to be Langmuir adsorption model for these affinity systems. In addition, competitive adsorption experiments were performed to display selectivity of the pesticide imprinted nanofilms. The prepared sensor was also efficiently applied for the selective detection of amitrole in green pepper.Öğe Role of propolis on biochemical parameters in kidney and heart tissues against L-NAME induced oxidative injury in rats(Taylor & Francis Inc, 2014) Talas, Zeliha Selamoglu; Ozdemir, Ilknur; Ciftci, Osman; Cakir, Oguz; Gulhan, Mehmet Fuat; Pasaoglu, Oguz MuratNitric oxide (NO), produced by endothelial NO synthase, is recognised as a central antiinflammatory and antiatherogenic principle in the vasculature. Epidemiological and clinical studies have demonstrated that a growing list of natural products, as components of the daily diet or phytomedical preparations, may improve vascular function by enhancing NO bioavailability. In this article, we investigated antioxidant effects of propolis on biochemical parameters in kidney and heart tissues of acute NO synthase inhibited rats by N-omega-nitro-L-arginine methyl ester (L-NAME). There was increase (p < 0.001) in the activities of catalase and malondialdehyde levels in the L-NAME treatment groups when compared with control rats, but NO levels were decreased in both kidney and heart tissues. There were statistically significant changes (p < 0.001) in these parameters of L-NAME + propolis treated rats as compared with L-NAME-treated group. In summary, propolis may influence endothelial NO production.Öğe Role of Propolis on Oxidative Stress in Fish Brain(Iran Univ Medical Sciences, 2013) Kakoolaki, Shapour; Talas, Zeliha Selamoglu; Cakir, Oguz; Ciftci, Osman; Ozdemir, IlknurIntroduction: Cypermethrin causes its neurotoxic effect through voltage-dependent sodium channels and integral protein ATPases in the neuronal membrane. Brain and nerve damage are often associated with low residual level of pesticides. In vitro and in vivo studies have also shown that pesticides cause free radical-mediated tissue damage in brain. Propolis has antioxidant properties. The main chemical classes found in propolis are flavonoids and phenolics. Bioflavonoids are antioxidant molecules that play important roles in scavenging free radicals, which are produced in neurodegenerative diseases and aging. Methods: To determine the protective role of propolis, rainbow trouts were treated with cypermethrin, followed by biochemical analyses of brain tissue. Fish were divided into four groups: control, propolis-treated, cypermethrin-treated, and cypermethrin+propolis-treated. Results: In fish brains, catalase (CAT) activity decreased (P=0.001) and malondialdehyde (MDA) level increased (P=0.001) in cypermethrin-treated group compared to control group. In cypermethrin+propolis-treated group CAT activity increased (P=0.001) and MDA level decreased (P=0.001) compared to cypermethrin group. Discussion: The results demonstrated that the negative effects, observed as a result of cypermethrin treatment, could be reversed by adding supplementary propolis. Propolis may improve some biochemical markers associated with oxidative stress in fish brain, after exposure to cypermethrin.Öğe ROLE OF PROPOLIS ON OXIDATIVE STRESS IN VARIOUS TISSUES OF FISH(Parlar Scientific Publications (P S P), 2014) Aldemir, Osman Selcuk; Selamoglu, Zeliha; Gulhan, Mehmet Fuat; Cakir, Oguz; Ozdemir, Ilknur; Dastan, Sevgi Durna; Dogan, HusnuThe aim of this study was to investigate the therapeutic effects of propolis on biochemical parameters in tissues of rainbow trout (Oncorhynchus mykiss) exposed to cypermethrin. Cypermethrin is a potential toxic pollutant that directly threats the aquatic ecosystems and environment. Sublethal cypermethrin concentration of 0.0082 ppm was applied to the fish for 96 h. Propolis is a natural product collected from plants by honey bees. Its polyphenolic components, caffeic acid derivatives and flavonoids in particular, are matter of interest because of their strong antioxidant properties. Therapeutic concentration of propolis has been determined as 10 ppm in a previous study. Herein, malondialdehyde (MDA) levels and catalase (CAT) activities were determined in spleen and heart tissues of rainbow trouts. Results showed that CAT activities and MDA levels increased (P <= 0.001) in tissues of fish exposed to cypermethrin compared to control group. CAT activities and MDA levels in the tissues of fish decreased in cypermethrin+propolis group (P <= 0.001) compared to cypermethrin group. Propolis (10 ppm) on the tissues of the rainbow trout showed significant therapeutic effects. Propolis may serve as an antitoxic agent against pesticide toxicity to aquatic animals.
