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  • Öğe
    Potential protective effect of hesperidin (Vitamin P) against hlyphosate-induced spermatogenesis damage in male rats: biochemical and histopathological findings on reproductive parameters
    (MDPI, 2024) Güngör, Şükrü; Kırıkkulak, Murat; Denk, Barış; Gülhan, Mehmet Fuat; Güleş, Özay; Budak, Duygu; İnanç, Muhammed Enes; Avdatek, Fatih; Yeni, Deniz; Taşdemir, Umut
    The aim of this study was to investigate the effectiveness of hesperidin (HES) on testicular histopathological changes, biochemical changes, and semen characteristics in rats exposed to glyphosate (GLP). The control group was given a normal diet devoid of GLP and HES, the HES group was given 100 mg/kg/day HES with the normal diet, the GLP group was given GLP at the LD50/10 dose of normal feed, which was 787.85 mg/kg/day, and the GLP + HES group was given normal feed containing 787.85 mg/kg/day LD50/10 dose of GLP in addition to 100 mg/kg/day HES. GLP administration reduced sperm motility, sperm plasma membrane integrity, glutathione levels, and total antioxidant levels in the testicular tissues of rats. Moreover, it caused an increase in right testis and left epididymis weights, abnormal sperm counts, malondialdehyde levels, total oxidant status, and DNA damage. The HES treatment showed curative effects on these parameters. Furthermore, HES was effective in lessening the histopathological damage that was caused by GLP. The results showedthat HES protects spermatological parameters and DNA integrity, improves antioxidant defenses, and lowers the damage and lipid peroxidation caused by GLP in testicular tissue.
  • Öğe
    Physico?chemical and microbiological properties of water kefr produced from carob (Ceratonia siliqua L.) sherbet
    (The Korean Society of Food Science and Technology, 2024) Gülhan, Mehmet Fuat; Gülhan, Ayça; Düşgün, Cihan
    In this study, sugar-free (A) and sugar-added (B) formulations of carob sherbet were fermented with water kefir grains. After 48 h of fermentation, the pH and total soluble solid content level (TSS) of A and B decreased, while the titratable acidity (TA) value increased. At the end of fermentation, Ave B formulations were stored at 4 °C for 28 days. Fermented sherbets’ 2,2?-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging activity decreased with storage. A had 75.3% DPPH radical scavenging activity on day 0th, whereas B had 77.0%. B had less total phenolic content (TPC) than fermented A on day 0. TPC values decreased significantly, notably on days 21st and 28th of storage. After fermentation, A had more gallic acid, hesperidin, p-coumaric acid, rosmarinic acid, and syringic acid than B. A had 2.21% sucrose before fermentation and 0.95% after. On 14th days of storage, potassium and calcium had the greatest mineral levels. Compared to A, B gave higher microbial count values (Lactobacillus sp., Lactococcus sp. total mesophilic aerobic bacteria, and yeast) in the microbiological analysis results at the end of fermentation and during storage.
  • Öğe
    Effect of biochars produced at different pyrolysis temperatures on Ammonium (NH4+) and Nitrate (NO3-) Leaching: Column experiment
    (Hasan ÖNDER, 2024) Gence, Cabir Çağrı; Erdem, Halil
    Nitrogen (N) leaching from agricultural soils is a global problem with negative effects on both human health and the environment. Efforts should be made to increase the efficiency of use of plant nutrients and minimize N losses from terrestrial ecosystems to aquatic ecosystems. In this study, the effects of different doses (%0, %1 and %2) of biochar obtained from corn cob and rice husk biomass, which are agricultural production residues, at three different temperatures, on ammonium (NH4+) and nitrate (NO3-) leaching in a coarse-textured soil were investigated. Polyethylene (PE) columns with a diameter of 70 mm and a height of 20 cm were used in the study, which was carried out in three replications according to the randomized plots experimental design. Total nitrogen (27 kg N da-1) and water amounts (969 mm) used for 6 tons da-1 yield of sugar beet were applied. Total water was given to each column in equal volume using drip adjustment sets at one-week intervals, simulating 6 irrigation periods, and the leaked water was collected in each irrigation period and NO3- and NH4+ concentrations were determined. Applications of 1 and 2 doses of corn and rice biochars obtained at three different pyrolysis temperatures caused a significant decrease in NH4+ concentrations leaching from the column. Similarly, biochar applications (especially 2% dose) caused a significant decrease in NO3- concentrations leaching from the column. While the total NO3- concentration leaching from the control columns was 149.23 mg kg-1, 2% dose of rice husk biochars at 300, 400 and 500 ? temperature applications caused a decrease in the total NO3- concentrations washed from the column by 51%, 55% and 51%, respectively. The results revealed that biochar applications significantly reduced nitrogen leaching from the soil.
  • Öğe
    Structural dynamics and anti-biofilm screening of novel imidazole derivative to explore their anti-biofilm inhibition mechanism against Pseudomonas Aeruginosa
    (Taylor and Francis Ltd., 2024) Mehmood, Shahab; Hussain, Mumtaz; Bux, Khair; Hussain, Zahid; Raza Shah, Muhammad; Ali Jakhrani, Mushtaque; Ali Channar, Pervaiz; Begum, Irshad; Saboor, Rukhsana; Yıldız, Cem B.; Ali, Kashif; Herwig, Ralf
    The biofilm formation is still prevalent mechanism of developing the drug resistance in the Pseudomonas aeruginosa, gram-negative bacteria, known for its major role in nosocomial, ventilator-associated pneumonia (VAP), lung infections and catheter-associated urinary tract infections. As best of our knowledge, current study first time reports the most potent inhibitors of LasR, a transcriptional activator of biofilm and virulence regulating genes in, Pseudomonas aeruginosa LasR, utilizing newly functionalized imidazoles (5a-d), synthesized via 1,3-dipolar cycloaddition using click approach. The synthesized ligands were characterized through Mass Spectrometry and 1H NMR. The binding potency and mode of biding of ligands. Quantum Mechanical(QM) methods were utilized to investigate the electronic basis, HOMO/LUMO and dipole moment of the geometry of the ligands for their binding potency. Dynamics cross correlation matrix (DCCMs) and protein surface analysis were further utilized to explore the structural dynamics of the protein. Free energy of binding of ligands and protein were further estimated using Molecular Mechanical Energies with the Poisson–Boltzmann surface area (MMPBSA) method. Molecular Docking studies revealed significant negative binding energies (5a ? 10.33, 5b ?10.09, 5c ? 10.11, and 5d ?8.33 KJ/mol). HOMO/LUMO and potential energy surface map estimation showed the ligands(5a) with lower energy gaps and larger dipole moments had relatively larger binding potency. The significant change in the structural dynamics of LasR protein due to complex formation with newlyfunctionalized imidazoles ligands.
  • Öğe
    Cryopreservation of ram semen: baicalein efficiency on oxidative stress, chromatin integrity, viability and motility post thaw
    (Frontiers Media SA, 2024) Avdatek, Fatih; Güngör, Şükrü; Gülhan, Mehmet Fuat; İnanç, Muhammed Enes; Olğaç, Kemal Tuna; Denk, Barış; Yeni, Deniz; Taşdemir, Umut
    Baicalein (B) has potential antioxidant properties, but it has not been tested as a ram semen extender. This study aimed to assess the impact of B on various sperm parameters and determine its potential influence on semen quality after the freeze-thawing process. During the breeding season, ejaculates were obtained from four rams with the aid of an artificial vagina. The collected mixed semen samples were divided into four groups: control (C; 0), B0.5 (0.5 mM), B1 (1 mM), and B2 (2 mM). After semen extension, the samples were loaded into 0.25 mL straws and stored for 2 h at 4°C prior to freezing in liquid nitrogen vapor and thawed in a water bath at 37°C. Among the groups, B0.5 demonstrated the highest progressive motility results, while B1 and B2 exhibited reduced motility (p < 0.05). In terms of high mitochondrial membrane potential, plasma membrane and acrosome integrity, and viability, B0.5 showed significantly superior outcomes to the other B groups (p < 0.05), although it was not significantly better than C. B1 displayed the highest plasma membrane integrity levels (p < 0.05). Notably, B2 displayed the lowest total antioxidant status levels among the groups (p < 0.05). The findings of this study suggested that the in vitro spermatological characteristics of ram spermatozoa such as progressive motility and chromatin integrity can be protected from the freeze-thawing process by using the 0.5 mM dose of baicalein as a semen extender. The treatment of sperm freezing might benefit from further in-depth research on the role of B in the improvement of cryoinjury and its underlying processes.
  • Öğe
    Dianionic and Neutral Diboron-Centered Classical Diradicaloids
    (American Chemical Society, 2024) Elvers, Benedict J.; Das, Ayan; Chrysochos, Nicolas; Uddin, Sk Imraj; Gangber, Tejaswinee; Gangber, Tejaswinee
    Herein, we report the syntheses and electronic structures of crystalline dianionic as well as neutral diboron-centered classical diradicaloids as boron analogues of classical Thiele, Chichibabin, and Müller (this only for dianionic diradicaloids!) hydrocarbons. These are based on borane radical anion and NHC-stabilized boryl radical spin carriers, respectively. All these dianionic diboron-centered diradicaloids exhibit triplet population at room temperature regardless of the ?-conjugated spacer: p-phenylene, p,p?-biphenylene, or p,p?-terphenylene. In the case of neutral diboron-centered diradicaloids, the employed ?-conjugated spacer plays a crucial role for the triplet population at room temperature: EPR inactive for p-phenylene vs EPR active for p,p?-biphenylene. The findings emphasize the importance of the spin carriers for the resulting ground-state: borane radical anion vs NHC-stabilized boryl radical along with the pivotal role of the ?-conjugated spacer as spin-coupler between two spins. Notably, 100 years (a century) after the first report by Krause of the triphenyl borane radical-anion, being isoelectronic to the triphenylmethyl radical, we convey borane radical anion-based diradicaloids. Furthermore, while donor-stabilized boryl radicals were introduced in the 1980s by Giles and Roberts, said concept is herewith being extended to NHC-stabilized boryl radical-based diradicaloids.
  • Öğe
    Comment on "Disclosing Cyclic(Alkyl)(Amino)Carbenes as a One-Electron Reductant: Synthesis of Acyclic(Amino)(Aryl)Carbene-Based Kekulé Diradicaloids"
    (Wiley-VCH - Home, 2023) Maiti, Avijit; Elvers, Benedict J.; Bera, Sachinath; Lindl, Felix; Krummenacher, Ivo; Ghosh, Prasanta; Braunschweig, Holger; Yıldız, Cem B.; Schulzke, Carola
    The authors would like to correct a misassignment of an EPR spectrum in the title paper (https://doi.org/10.1002/chem. 202104567). The authors of the original paper reported the one-electron oxidation of the cyclic(alkyl)(amino)carbene (CAAC) 1 to produce the intermediate iminium radical cation 2, as deduced from the high isolated yield of the hydrogen abstraction product 3 (Figure 1). By low-temperature (200 K) EPR spectroscopy, we observed a weak transient, three-line EPR spectrum with a g-factor of 2.0043 and a 14N hyperfine splitting (hfs) of a( 14N)=5.9 G, which we attributed to the radical cation 2 (the spectrum was depicted as Figure 1b, in the TOC cover image, in the Cover Feature (https://doi.org/10.1002/chem. 202201219), and as Figure S46 of the original paper). However, as one of the present authors (H.G.K.) later pointed out, the foregoing EPR parameters, in particular the g-factor, would not be in agreement with the proposed vinyl-type ?-radical cation.
  • Öğe
    Intramolecular donor-stabilized tetra-coordinated germanium(iv) di-cations and their Lewis acidic properties
    (Royal Society of Chemistry, 2023) Yıldız, Cem Burak; Khan, Souvik; Gonnade, Rajesh G.; Majumdar, Moumita
    We report the first examples of intramolecular phosphine-stabilized tetra-coordinated germanium(iv) di-cationic compounds: [LiPr2Ge][CF3SO3]23iPr and [LPh2Ge][CF3SO3]23Ph (LiPr = 6-(diisopropylphosphanyl)-1,2-dihydroacenaphthylene-5-ide; LPh = 6-(diphenylphosphanyl)-1,2-dihydroacenaphthylene-5-ide). The step wise synthetic strategy involves the isolation of neutral and mono-cationic Ge(iv) precursors: [LiPr2GeCl][X] (X = GeCl31iPr, OTf 2iPr), [LPh2GeCl2] 1Ph and [LPh2GeCl][OTf] 2Ph. Both 3iPr and 3Ph exhibit constrained spiro-geometry. DFT studies reveal the dispersion of di-cationic charges over P-Ge-P sites. Anion or Lewis base binding occurs at the Ge site resulting in relaxed distorted trigonal bipyramidal/tetrahedral geometry. 3iPr and 3Ph activate the Si-H bond initially at the P-site. The hydride ultimately migrates to the Ge-site rapidly giving [LPh2GeH][CF3SO3] 3PhH, while sluggishly forming [LiPr2GeH][CF3SO3] 3iPrH. Compounds 3iPr and 3Ph were tested as catalysts for the hydrosilylation of aromatic aldehydes. While catalytic hydrosilylation proceeded via the initial Et3Si-H bond activation in the case of 3iPr, compound 3Ph as a catalyst showed a masked Frustrated Lewis Pair (FLP) type reactivity in the catalytic cycle.
  • Öğe
    Effects of Nitrogen and Zinc Fertilization on Alleviating Cadmium Accumulation in Durum Wheat Grains
    (Taylor and Francis Ltd., 2023) Tosun, Yener Kortan; Erdem, Halil; Gence, Cabir Çağrı
    Cadmium (Cd) accumulation in durum wheat (Triticum durum L.) is of particular concern compared to the other commonly cultivated cereals. This study was conducted to determine the effects of zinc (Zn) and nitrogen (N) applications on grain Cd concentration of durum wheat grown in a Cd contaminated soil. The experimental design consisted of randomized plots with four replications. The treatments included low and adequate (0.05 and 5 mg kg?1) Zn doses, and inadequate, optimal and high (200, 400 and 600 mg kg?1) N doses. Cadmium application rates were 0 and 5 mg kg?1. The findings demonstrated that Cd application caused a significant increase in grain Cd concentrations, and a decrease in straw and grain yields under low and adequate doses of Zn and all N doses. However, increasing N applications with adequate soil Zn caused an increase in the straw and grain yields and a significant decrease in grain Cd concentration. The grain Cd concentration in low Zn and optimum N treatment under Cd application was 6206 µg kg?1, while the grain Cd concentration decreased by 26.3% (4574 µg kg?1) in the Zn and optimum N treatment. In addition, the grain Zn concentration of durum wheat under low soil Zn conditions was decreased in Cd application, whereas the grain Zn concentration increased in Cd application under adequate soil Zn concentration. The results revealed that combined application of N and Zn in Zn deficient soils is highly effective at decreasing Cd accumulation in wheat grains compared to individual applications.
  • Öğe
    A Zwitterionic Tetrastanna(II) Cyclic Crown
    (John Wiley and Sons Inc, 2023) Sahoo, Padmini; Chibde, Purva; Das, Satyabrata; Banerjee, Subhrashis; Vanka, Kumar; Gonnade, Rajesh G.; Yıldız, Cem. B.; Majumdar, Moumita
    A 12-membered zwitterionic tetrastanna(II) cycle 1 having a crown ether-like topology has been isolated from the deprotonation of 1,1?-methylenediimidazole (B) with two equivalents of Sn[N(SiMe3)2]2 (A). The solid-state structure and NMR analysis confirms the tetrastanna(II) cycle 1 to be comprised of two stannate(II) and two stannyliumylidene ion pairs in alternating positions of the heterocycle. Computational analysis shows greater nucleophilicity at the proximally located stannate(II) centers. Nonetheless, the tetrastanna(II) cycle 1 remains poorly reactive due to engagement of SnII lone pair electrons in intramolecular donor-acceptor interactions. Simple deprotonation reaction between Sn[N(SiMe3)2]2 (A) and N-(diisopropylphenyl)imidazole (C) in equimolar ratio has led to a stannylene 2, involving the formation of a Sn?C covalent bond with the anionic imidazol-2-yl carbon center along with the release of NH(SiMe3)2. Compound 2 exists as a dimer, where the unsubstituted ring nitrogen atom coordinated intermolecularly to the other stannylene center.
  • Öğe
    Reduction of 2-H-substituted pyrrolinium cations: the carbon-carbon single bond in air stable 2,2?-bipyrrolidines as a two-electron-source
    (Royal Society of Chemistry, 2023) Nayak, Mithilesh Kumar; Elvers, Benedict J.; Mandal, Debdeep; Das, Ayan; Ramakrishnan, Raghunathan; Mote, Kaustubh R.; Schulzke, Carola; Yıldız, Cem Burak; Jana, Anukul
    Reduction of 2-H-substituted pyrrolinium cations via initially formed secondary radicals results in either dimerisation or H-abstracted products, while the outcome depends on the N-substituents. The resultant central carbon-carbon single bond in the dimerised 2,2?-bipyrrolidine derivatives can be oxidised chemically and electrochemically. The notably air and moisture-stable dimers were subsequently utilised as a source of two electrons in various chemical transformations.
  • Öğe
    Investigation of the effects of syringic acid supplemented to Tris semen diluent on ram semen freezability
    (John Wiley and Sons Inc, 2023) Avdatek, Fatih; İnanç, Muhammed Enes; Gülhan, Mehmet Fuat; Güngör, Şükrü; Yeni, Deniz; Olğaç, Kemal Tuna; Denk, Barış; Taşdemir, Umut
    To the best of our knowledge, no research has been conducted to test the effects of syringic acid (SA) on ram semen freezing within the scope of natural antioxidants added to semen extenders. Therefore, this study had two main objectives. First, to test whether adding SA to ram semen freezing extender has a protective effect and contributes positively to sperm kinetic, plasma and acrosome integrity, mitochondrial membrane potential, lipid peroxidation, oxidant and antioxidant and DNA damage parameters after thawing. Second, it was to determine at what concentration the SA supplemented to the extender could be applied by in vitro studies by preserving the fertilization ability of frozen semen at the highest level. In the study, six individuals of Sönmez rams were used. The semen was collected from the rams using an artificial vagina and pooled. The pooled semen was divided into five different groups and extended with 0, 0.5, 1, 2 and 4 mM SA (control C, SA0.5, SA1, SA2 and SA4, respectively). After dilution, the semen samples were kept at 4°C for 3 h, then loaded into 0.25 mL straws and frozen in liquid nitrogen vapour. The SA1 and SA2 groups were higher plasma membrane and acrosome integrity (PMAI), high mitochondrial membrane potential (HMMP), plasma membrane integrity and motility compared to other groups (p <.05). It was observed that SA supplemented to the Tris extender significantly reduced DNA damage, and the lowest values were obtained especially in the SA1 and SA2 treatments (p <.05). Also, lowest MDA level was determined at the SA1 and this was statistically significant compared to SA4 and C (p [removed]
  • Öğe
    Coordination Chemistry of the Antimony(III) and Bismuth(III) Cations using Bis(?-iminopyridine) as Ligand
    (John Wiley and Sons Inc, 2023) Haldar, Hritwik; Yıldız, Cem Burak; Majumdar, Moumita
    Bis(alpha-iminopyridine) L has been employed as the redox non-innocent Schiff-base ligand to coordinate with cationic antimony(III) and bismuth(III) centers. Mono- and di- cationic compounds: [LSbCl2][CF3SO3] 1, [LBiCl2][CF3SO3] 2, [LSbCl2]2[Sb2Cl8] 3, [LBiCl2]2[Bi2Cl8] 4, [LSbCl][CF3SO3]2 5, [LBiCl][CF3SO3]2 6 have been isolated and characterized using single crystal X-ray crystallography in the solid-state and solution-state NMR studies. These compounds have been prepared from PnCl3 (Pn=Sb, Bi) and chloride abstracting agent such as Me3SiCF3SO3 or AgCF3SO3 in the presence of L. The Bi tri-cationic species forms heteroleptic compound 7, being coordinated by two types of Schiff-base donors L and L?. The latter has been in situ generated by the cleavage of one of the two imines present in L.
  • Öğe
    Cryopreservation of Ram Semen Using Capsaicin Supplemented Tris Extender
    (Afyon Kocatepe Üniversitesi, 2023) İnanç, Muhammed Enes; Avdatek, Fatih; Güngör, Şükrü; Gülhan, Mehmet Fuat; Olgaç, Kemal Tuna; Denk, Barış; Yeni, Deniz; Taşdemir, Umut
    In this study, it was designed to reveal the effects of capsaicin on oxidative stress and freezability of ram semen. Ejaculates were taken from Sönmez rams and divided into five specimens and diluted with extender at different rates (4 mM, 2 mM, 1 mM, 500 ?M) with and without capsaicin (control; C). Semen samples were thawed with a 37°C water bath for 30 seconds for post-thawed analysis. At the end of the study, sperm motility and kinetic parameters, plasma membrane acrosome integrity (PMAI), mitochondrial membrane potential (MMP), DNA damage, oxidant and antioxidant parameters were analyzed. A decrease was observed in the groups containing capsaicin compared to the C in terms of progressive, total motility and kinetic parameters (p<0.05). Besides, positive results were not obtained DNA integrity, PMAI and MMP (p<0.05). In conclusion; it was determined that capsaicin added to Tris extender did not have a positive effect on oxidative stress and freezing of ram semen.
  • Öğe
    Effect of solvent concentrations on antioxidant activity and biochemical parameters of adzuki bean (Vigna angularis) sprouts at different germination times
    (Balıkesir Üniversitesi, 2022) Gülhan, Mehmet Fuat
    In this study were determined DPPH radical scavenging power, metal-ion chelating activity, gamma aminobutyric acid and phytic acid levels, total phenolic substance content, extraction yield in water and various organic solvents (acetone, n-hexane and ethanol), concentrations (50, 70 and 90%) and germination times (0, 24, 48, 72, 96 and 120 h) of adzuki bean (Vigna angularis) sprouts. The extraction yield ranged from 11.47% (H3) to 28.55% (E1). The highest DPPH radical scavenging capacity was determined at E2 concentration (2.978 ?mol/g DW) for 120 h (P<0.05). E3 (1.744 mg EDTA equivalent/100 g) and A3 (1.145 mg EDTA equivalent/100 g) showed the highest metal chelating activity after 48h of germination. This activity decreased in the germination period from 48 h to 120 h (P<0.05). When different solvent concentrations were compared no significant change (P>0.05) in gamma aminobutyric acid and phytic acid contents at 0, 24 and 48 h analyses. The highest gamma aminobutyric acid content was detected to A1 (67.29 mg/100 g DW) and H1 (69.17 mg/100 g DW) concentrations at 120 h (P<0.05). No significant changes were found in total phenol content in all solvent concentrations in 48 h (P>0.05). At the end of 120 h, total phenolic components were determined in the lowest levels in W and the highest concentrations in E2 (P<0.05). These results showed that adzuki bean seeds may be more effective in these parameters, depending on the increase in the activities of bioactive components and the decrease in anti-nutritional factors, and the concentration in water and aqueous organic solvents with the increase of germination time.
  • Öğe
    Air and moisture stable para- and ortho-quinodimethane derivatives derived from bis-N-Heterocyclic olefins
    (American Chemical Society, 2023) Jana, Subhadip; Elvers, Benedict J.; Patsch, Sebastian; Sarkar, Pallavi; Krummenacher, Ivo; Nayak, Mithilesh Kumar; Maiti, Avijit; Chrysochos, Nicolas; Pati, Swapan K.; Schulzke, Carola; Braunschweig, Holger; Yıldız, Cem Bural
    Herein we report the development of a new methodology for the synthesis of various quinodimethane derivatives under two-electron oxidation of bis-Nheterocyclic olefins linked by different pi-conjugated aromatic spacers. In case of paraand ortho-phenylene bridge, we obtained air and moisture stable diimidazolium paraand ortho-quinodimethane derivatives. Analogues of the para-phenylene spacer such as tetrafluoro-p-phenylene and p-anthracene also led to the corresponding air and moisture stable quinodimethane derivatives. This emphasizes the influence of imidazolium substituents which facilitate the air and moisture stability of the quinodimethane derivatives. Differences were observed for the electron transfer processes: two one-electron vs one two-electron redox transitions between bis-N-heterocyclic olefins and diimidazolium-quinodimethanes depending on the employed pi-conjugated aromatic spacer. The formation of the pi-conjugated radical-cations, transient redox intermediates between bis-N-heterocyclic olefins and diimidazolium-quinodimethanes, was addressed by an EPR investigation.
  • Öğe
    A new substrate and nitrogen source for traditional kombucha beverage: stevia rebaudiana leaves
    (Springer, 2023) Gülhan, Mehmet Fuat
    Recently, the use of different herbal products as carbon sources instead of black and green tea in the preparation of traditional kombucha has been investigated. In this study, functional kombucha was prepared by adding Stevia rebaudiana Bertoni leaves, which have special organoleptic properties, to kombucha medium, and some properties of the beverage were analyzed. Tea blends were determined as 100% green tea (control = C), 75% green tea (GT) + 25% Stevia (ST), 50% GT + 50% ST, and 100% ST. On the 15th day of fermentation, gluconic acid (43.12 ± 0.01 g/L) was detected as dominant organic acid in GT75 + ST25 samples compared to group C (p < 0.05). According to physicochemical parameters that determine the drinkability properties of prepared teas, the best results were in GT25 + ST75 compared to group C (p < 0.05). It proved that the highest activity was in GT25 + ST75 on the 10th day in the groups that applied different antioxidant tests (DPPH, MCA, and CUPRAC). The antimicrobial activities of kombucha at 25, 50, 75, and 100% concentrations of GT and ST reached the highest levels in the GT25 + ST75 group in samples after 10 days of fermentation for all selected microorganisms. The results prove that GT25 + ST75 kombucha is a functional product with high drinkability on the 10th day of fermentation and also more beneficial for health due to the phenolic compounds from both green tea and Stevia. Stevia rebaudiana leaves can be suggested that be used as a new substrate and nitrogen source for kombucha production.
  • Öğe
    Carbodicarbenes and striking redox transitions of their conjugate acids: influence of NHC versus CAAC as donor substituents
    (John Wiley and Sons Inc, 2023) Dolai, Ramapada; Kumar, Rahul; Elvers, Benedict J.; Pal, Pradeep Kumar; Joseph, Benson; Sikari, Rina; Nayak, Mithilesh Kumar; Yıldız, Cem Burak
    Herein, a new type of carbodicarbene (CDC) comprising two different classes of carbenes is reported; NHC and CAAC as donor substituents and compare the molecular structure and coordination to Au(I)Cl to those of NHC-only and CAAC-only analogues. The conjugate acids of these three CDCs exhibit notable redox properties. Their reactions with [NO][SbF6] were investigated. The reduction of the conjugate acid of CAAC-only based CDC with KC8 results in the formation of hydrogen abstracted/eliminated products, which proceed through a neutral radical intermediate, detected by EPR spectroscopy. In contrast, the reduction of conjugate acids of NHC-only and NHC/CAAC based CDCs led to intermolecular reductive (reversible) carbon–carbon sigma bond formation. The resulting relatively elongated carbon–carbon sigma bonds were found to be readily oxidized. They were, thus, demonstrated to be potent reducing agents, underlining their potential utility as organic electron donors and n-dopants in organic semiconductor molecules.
  • Öğe
    Thymoquinone improves motility, plasma membrane integrity and DNA integrity of frozen-thawed ram semen
    (Wiley, 2022) İnanc, Muhammed Enes; Güngör, Şükrü; Avdatek, Fatih; Yeni, Deniz; Gülhan, Mehmet Fuat; Olgaç, Kemal Tuna; Denk, Barış; Taşdemir, Umut
    The aim of this study was to determine the effects of thymoquinone (TQ), which is the most essential active compound of Nigella sativa, on the spermatological parameters of ram semen during cryopreservation. Ejaculates were collected from five Sonmez rams using an artificial vagina and extended with Tris-based extender not containing TQ (control, 0 mu g/ml TQ) and containing 10, 25, 50 and 100 mu g/ml TQ. The extended semen samples were equilibrated in a + 4 degrees C cold cabinet for 2 h. After 2 h, the samples were loaded into 0.25 ml French straws. The straws were frozen by liquid nitrogen vapour and stored in a liquid nitrogen container (-196 degrees C). The frozen straws were thawed in a water bath (37 degrees C for 30 s) and evaluated in terms of motility characteristics, plasma membrane and acrosome integrity, mitochondrial reactive oxygen species levels, lipid peroxidation levels, DNA damage and biochemical alterations (oxidative stress index, malondialdehyde and glutathione). TQ100 had higher total motility (53.59 +/- 3.01) and progressive motility (19.84 +/- 1.44; not significantly different from TQ25 and TQ50) compared to the control and TQ10 (p < 0.05). According to the results of the analyses on motility characteristics, there were significant differences between the groups in terms of curvilinear velocity (VCL), amplitude of lateral head displacement (ALH) and linearity (LIN; p < 0.05). The highest DNA damage was detected in the control group (p < 0.05). TQ50 had higher plasma membrane and acrosome integrity (59.56 +/- 5.92) compared to the control and TQ25 (p < 0.05) but not significantly different from TQ10 and TQ100. The lowest mitochondrial reactive oxygen species levels were detected in TQ50 and TQ100 (p < 0.05). There were no significant differences among the groups in terms of their oxidative stress index, lipid peroxidation, malondialdehyde and glutathione levels (p > 0.05). According to the results, it could be concluded that supplementing 50 or 100 mu g/ml TQ to Tris extenders that were used for ram semen cryopreservation showed a positive effect on motility, plasma membrane integrity and acrosome integrity, and it reduced DNA damage and mitochondrial reactive oxygen species levels.
  • Öğe
    The oxidation state in low-valent beryllium and magnesium compounds
    (The Royal Society of Chemistry, 2022) Gimferrer, Marti; Danes, Sergi; Vos, Eva; Yıldız, Cem Burak; Corral, Ines; Jana, Anukul; Salvador, Pedro; Andrada, Diego M.
    Low-valent group 2 (E = Be and Mg) stabilized compounds have been long synthetically pursued. Here we discuss the electronic structure of a series of Lewis base-stabilized Be and Mg compounds. Despite the accepted zero(0) oxidation state nature of the group 2 elements of some recent experimentally accomplished species, the analysis of multireference wavefunctions provides compelling evidence for a strong diradical character with an oxidation state of +2. Thus, we elaborate on the distinction between a description as a donor-acceptor interaction L(0) ? E(0) reversible arrow L(0) and the internally oxidized situation, better interpreted as a diradical L(-1) -> E(+2) <- L(-1) species. The experimentally accomplished examples rely on the strengthened bonds by increasing the pi-acidity of the ligand; avoiding this interaction could lead to an unprecedented low-oxidation state.