Beslenme ve Diyetetik Bölümü Koleksiyonu

Permanent URI for this collectionhttps://hdl.handle.net/20.500.12514/223

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Changes in volatile compounds, sugars and organic acids of different spices of peppers (Capsicum annuum L.) during storage
(FOOD CHEMISTRY, 2020) Korkmaz, Aziz; Atasoy, Ahmet Ferit; Hayaloglu, Ali Adnan
Changes in sugars, organic acids and volatile compounds (VC) of red pepper flakes (RPF), traditional (TRI), and industrial (INI) isot peppers were evaluated during one year storage at the room condition. The changes in the flavor components were significantly affected by the production methods and storage time. Glucose content decreased gradually along storage and reduced by about 21.23, 47.22 and 56.65% for TRI, INI and RPF, respectively. However, fructose decreased significantly only in RPF (11.29%). Citric and succinic acids exhibited slight changes, but malic acid showed an increasing trend, especially in RPF (4-fold). Most of the VC in all samples decreased or disappeared after storage. The major quantitative losses in these compounds were found in TRI during the first 3 months as 81.76%. The storage was found to be caused deterioration flavor properties in red pepper spices and revealed the importance of appropriate storage conditions.
Corrosion behavior of mild steel in 1 M HCl with Cyclotrichium niveum as a green inhibitor
(Elsevier, 2024) Yıldız, Reşit; Arslanhan, Selim; Döner, Ali; Baran, Mehmet Fırat; Yıldız, Reşit
Recently, green inhibitors are replacing classical inhibitors in the acid cleaning industry due to very low cost, environmentally friendly and none toxic. In this study, Cyclotrichium niveum is used as a potential green corrosion inhibitor to investigate the corrosion behavior of mild steel (MS) in chloride solution using electrochemical, morphological, structural and quantum chemical methods. Fifty-three flavonoids are detected in methanol extract of cyclotrichium niveum by LC/ESI-MS/MS. While icorr values decreased, Rp and inhibition efficiencies values derived from electrochemical impedance spectroscopy (EIS) and linear polarization resistance (LPR) increased in increasing inhibitor concentrations. Maximum inhibition efficiency is found to be 97.3%, that is the almost highest value, when compared to previous studies and plant extract is classified as a mixed type inhibitor with respect to the potentiodynamic polarization (PDP). The model that best fits the experimental values is the Langmuir isotherm. The temperature effect is also studied in the range of 25–55 ○C. Higher activation energy is obtained in the presence of inhibitor, suggesting that it acts as an efficient inhibitor by forming a physical barrier to the charge and mass transfer reaction, leading to reduction in corrosion rate. Scanning electron and atomic force microscopies showed the more uniform, crack and pits free structure, confirming that there is a protective film over the MS surface for inhibited solution. XPS analysis showed the existence of C, O, and Fe atoms on the MS surface. Quantum chemical calculation manifested the adsorption mechanism associated with the electronic structure of the molecules. The findings of this work can be applicable in chemical cleaning process with acid treatment.
Effect of seasonal variation on lipid and fatty acid profile in muscle tissue of male and female Silurus triostegus
(SPRINGER INDIA, 2016) Kacar, Semra; Bashan, Mehmet; Oymak, Seyit Ahmet
Fatty acid (FA) compositions of total lipid, phospholipid (PL) and triacylglycerol (TAG) fractions have been determined in muscle tissues of Silurus triostegus. The distributions of saturated fatty acid (SFA), monounsaturated fatty acid (MUFA) and polyunsaturated fatty acid (PUFA) proportions were found to be different among total lipid, PL and TAG fractions from lipids in muscle tissues of the male and female S. triostegus in all seasons. Triacylglycerol contained a lower proportion of PUFA and a higher proportion of MUFA and SFA than PL while PL contained higher proportion of PUFA than proportion of MUFA and SFA compared to TAG. Triacylglycerol and PL fatty acid compositions in muscle tissues of the male and female fish species were found different. The most abundant fatty acids in the investigated seasons were palmitic acid (C16:0), stearic acid (C18:0), oleic acid (C18:1 n-9), palmitoleic acid (C16:1 n-7) and docosahexaenoic acid (C22:6 n-3). It was shown that the total lipid content and FA compositions in muscle tissues of the male and female S. triostegus were influenced by reproduction period and season.
Electrochemical Behavior of Pt Nano-Particles Dispersed on Cu/Ni Electrode in Alkaline Environment
(Pergamon-elsevier Science Ltd, 2024) Doslu, Serap Toprak; Doner, Ali
The development of a low-cost Pt-based electrocatalyst for industrial water splitting is important. In this study, to prepare cost-efficient Pt-based electrocatalyst for hydrogen evolution, Cu electrode is deposited with nickel (Cu/ Ni) and this surface is modified with Pt nanoparticles by electrodeposition method (Cu/Ni-Pt). The surface properties of the produced electrocatalysts are studied via X-ray diffraction (XRD), scanning electron spectroscopy (SEM), energy dispersive X-ray analysis (EDX), transmission electron microscopy (TEM) and atomic force microscopy (AFM). Characterizations demonstrated that the coating is homogeneous and compact. Hydrogen evolution and corrosion behaviors of prepared electrode (Cu/Ni-Pt) are examined in 1.0 M KOH solution using cyclic voltammetry (CV) and cathodic and anodic current-potential curves, electrochemical impedance spectroscopy (EIS). Tafel slope is determined to be 133 mV dec(-1) on Cu/Ni-Pt. Very high exchange current density (5.65 mA cm(-2)) and very low charge transfer resistance (0.91 Omega cm(2) at 1.05 V vs RHE) are measured again on this electrocatalyst. High activity is due to intrinsic activity of Pt and synergistic interaction of Pt and Ni. Besides, Cu/Ni-Pt exhibits so stable structure over 4 h without any current densities decay as well as showing good corrosion performance after long-term immersion times and these properties make it possible electrocatalyst with high corrosion resistant and activity in the water electrolysis systems.
The electrochemical synthesis and corrosion behaviour of TiO2/poly(indole-co-aniline) multilayer coating: Experimental and theoretical approach
(Arabian Journal of Chemistry, 2018) Toprak Döşlü, Serap; Doğru Mert, Başak; Yazıcı, Birgül
The aim of this study was to protect stainless steel against corrosion via poly (indole-co-aniline) with the help of titanium dioxide pre-coating. Different monomer ratios (1:1 and 1:9) wereapplied in order to determine the suitable chain composition to synthesize the copolymer in lithiumperchlorate containing acetonitrile. The structures, morphologies, electrochemical properties andcorrosion resistances of the mono and multi-layer coatings were investigated by Fourier-transform infrared spectra, scanning electron microscope, energy dispersive X-ray spectrometer,electrochemical impedance spectroscopy and anodic polarization. Furthermore the geometric struc-ture and electronic properties of indole, aniline, and indole-co-aniline (dimmer) molecules have beeninvestigated by quantum calculations. The results indicated that corrosion protection of copolymerswas increased via titanium dioxide pre-coating. The 1:1 copolymer coating showed better corrosionprevention than 1:9 coating. The correlation was determined between experimental and theoreticalparameters.
Green Synthesis of Silver Nanoparticles Derived from Papaver rhoeas L. Leaf Extract: Cytotoxic and Antimicrobial Properties
(MDPI, 2023) İpek, Polat; Yıldız, Reşit; Baran, Mehmet Fırat; Hatipoğlu, Abdülkerim; Baran, Ayşe; Sufianov, Albert; Beylerli, Ozal; Yıldız, Reşit
In the last few decades, the search for metal nanoparticles as an alternative to cancer treatments and antibiotics has increased. In this article, the spectroscopic (ultraviolet-visible (UV-vis), electron-dispersing X-ray (EDX), and Fourier transform infrared (FT-IR)), microscopic (field emission scanning electron microscope (FE-SEM), transmission electron microscope (TEM), and atomic force microscope (AFM)), structural (X-ray diffractometer (XRD) and zetasizer), and analytic (thermogravimetric/differential thermal analyzer (TGA-DTA)) characterization of the silver nanoparticles (AgNPs) produced from Papaver rhoeas (PR) L. leaf extract are presented. PR-AgNPs are generally spherical and have a maximum surface plasmon resonance of 464.03 nm. The dimensions of the manufactured nanomaterial are in the range of 1.47-7.31 nm. PR-AgNPs have high thermal stability and a zeta potential of 36.1 mV. The minimum inhibitory concentration (MIC) values (mg L-1) of PR-AgNPs on Staphylococcus aureus, Escherichia coli, Bacillus subtilis, Pseudomonas aeruginosa, and Candida albicans are 1.50, 0.75, 3.00, 6.00, and 0.37, respectively. In the study, the cytotoxic and proliferative effects of PR-AgNPs using the MTT (3-(4,5-dimethylthiazol-2-yl)-diphenyltetrazolium bromide) method on various cancer cell lines (CACO-2 (human colon adenocarcinoma cell), MCF-7 (human breast cancer cell), T98-G (glioblastoma multiforme cell), and healthy HUVEC (human umbilical vein endothelial cell)) cell lines are presented. After 24 and 48 h of the application, the half-maximum inhibitory concentration (IC50) values (mu g mL(-1)) of PR-AgNPs on HUVEC, CACO-2, MCF-7, and T98-G lines are 2.365 and 2.380; 2.526 and 2.521; 3.274 and 3.318; 3.472 and 3.526, respectively. Comprehensive in vivo research of PR-AgNPs is proposed to reveal their potential for usage in sectors such as nanomedicine and nanochemistry.
Natural phytotherapeutic antioxidants in the treatment of mercury intoxication-A review
(Tabriz University of Medical Sciences, 2018) Unsal V.
Heavy metals taken into the organism can make the toxic effects on the metabolism in various ways. For example, they may interact with proteins to alter and inhibit their enzymatic and structural functions. Mercury is one of the toxic elements that are widely distributed in nature. Mercury toxicity poses a serious threat to human health. It is an element that causes oxidative stress to increase in individuals, leading to tissue damage. Oxidative stress is the result of the imbalance between the production of oxidative species and cellular antioxidant defense. Phytotherapy continues to play an important role in health care. Natural phytotherapeutic antioxidants, exhibit a broad sequence of biological impacts, including anti-oxidative stress, anti-aging, anti-toxicicity and anticancer. Many studies have also shown that the phytotherapeutic agents play an important role in the removal of mercury from the tissue and in reducing oxidative stress. Our goal in this review was to investigate alternative ways of extracting the mercury in the tissue. © 2018 The Authors.
Toxicity of carbon tetrachloride, free radicals and role of antioxidants
(De Gruyter, 2020) Unsal, Velid; Çiçek, Mustafa; Sabancılar, İlhan
Several chemicals, including environmental toxicants and clinically useful drugs, cause severe cellular damage to different organs of our body through metabolic activation to highly reactive substances such as free radicals. Carbon tetrachloride is an organic compound of which chemical formula is CCl₄. CCl4 is strong toxic in the kidney, testicle, brain, heart, lung, other tissues, and particularly in the liver. CCl4 is a powerful hepatoxic, nephrotoxic and prooxidant agent which is widely used to induce hepatotoxicity in experimental animals and to create hepatocellular carcinoma, hepatic fibrosis/cirrhosis and liver injury, chemical hepatitis model, renal failure model, and nephrotoxicity model in recent years. The damage-causing mechanism of CCl4 in tissues can be explained as oxidative damage caused by lipid peroxidation which starts after the conversion of CCl4 to free radicals of highly toxic trichloromethyl radicals (•CCl₃) and trichloromethyl peroxyl radical (•CCl₃O2) via cytochrome P450 enzyme. Complete disruption of lipids (i.e., peroxidation) is the hallmark of oxidative damage. Free radicals are structures that contain one or more unpaired electrons in atomic or molecular orbitals. These toxic free radicals induce a chain reaction and lipid peroxidation in membrane-like structures rich in phospholipids, such as mitochondria and endoplasmic reticulum. CCl4-induced lipid peroxidation is the cause of oxidative stress, mitochondrial stress, endoplasmic reticulum stress. Free radicals trigger many biological processes, such as apoptosis, necrosis, ferroptosis and autophagy. Recent researches state that the way to reduce or eliminate these CCl4-induced negative effects is the antioxidants originated from natural sources. For normal physiological function, there must be a balance between free radicals and antioxidants. If this balance is in favor of free radicals, various pathological conditions occur. Free radicals play a role in various pathological conditions including Pulmonary disease, ischemia / reperfusion rheumatological diseases, autoimmune disorders, cardiovascular diseases, cancer, kidney diseases, hypertension, eye diseases, neurological disorders, diabetes and aging. Free radicals are antagonized by antioxidants and quenched. Antioxidants do not only remove free radicals, but they also have anti-inflammatory, anti-allergic, antithrombotic, antiviral, and anti-carcinogenic activities. Antioxidants contain high phenol compounds and antioxidants have relatively low side effects compared to synthetic drugs. The antioxidants investigated in CCI4 toxicity are usually antioxidants from plants and are promising because of their rich resources and low side effects. Data were investigated using PubMed, EBSCO, Embase, Web of Science, DOAJ, Scopus and Google Scholar, Carbon tetrachloride, carbon tetrachloride-induced toxicity, oxidative stress, and free radical keywords. This study aims to enlighten the damage-causing mechanism created by free radicals which are produced by CCl4 on tissues/cells and to discuss the role of antioxidants in the prevention of tissue/cell damage. In the future, Antioxidants can be used as a therapeutic strategy to strengthen effective treatment against substances with high toxicity such as CCl4 and increase the antioxidant capacity of cells.

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