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Öğe Improve the energy efficiency of the fruit freeze-drying through the predictive analysis(Elsevier, 2024) Öztuna Taner, Öznur; Çolak, Andaç BaturThe considerable energy expenditure involved in the freeze-drying of foods justifies the development of innovative engineering techniques. Artificial intelligence will facilitate mass balance and energy efficiency in future food freeze-drying processes. This study assessed the energy and manufacturing efficiency of the freeze-drying facility through the application of artificial intelligence. Two distinct artificial neural network models were created utilizing real-time data from a factory located in an industrial zone that processed freeze-dried vegetables and kiwi fruit. Analyzing energy efficiency values and production was done using network models constructed from 20 experimental data sets. The Levenberg-Marquardt approach was employed to train neural networks with a multilayer perceptron architecture. The neural network models' prediction values were compared with the experimentally acquired data, and their performance was examined using several performance criteria. The evaluations carried out for 20 different scenarios revealed overall energy efficiency rates ranging from 25.8 % to 64.5%. The considerable energy expenditure involved in the freeze-drying of foods justifies the development of innovative engineering techniques. Artificial intelligence will facilitate mass balance and energy efficiency in future food freeze-drying processesÖğe Determination of secondary metabolites of Cydonia oblonga (Quince) by LC-MS/MS method together with evaluation of its antioxidant and cholinergic potentials(ACG Publications, 2024) Dikici, Emrah; Altın, Sevgi; Alp, Cemalettin; Işık, Mesut; Köksal, Ekrem; Gülçin, İlhamiIn this study, quantification of secondary metabolites of Cydonia oblonga (Quince) leaves by LC-MS/MS and antioxidant, cholinergic and ?-Glycosidase activities were reported. LC-MS/MS analyses of the studied extract showed that the highest phenolic constituents of species were catechin (2024.9 ± 80.9 ?g/L), vanillic acid (1121.8 ± 39.3 ?g/L) and fumaric acid (486.7 ± 16.5 ?g/L). The ethanol extract of quince leaves inhibited the ?-glycosidase enzyme with an IC50: 0.6 ?g/mL value. In order to determine the anti-Alzheimer activity of the plant extract, inhibition studies were carried out on acetylcholinesterase (AChE) and butyrylcholinesterase (BChE) enzymes. The IC50 values of the plant extract were found to be 1.3 ?g/mL for AChE and 1.5 ?g/mL for BChE. In addition, free radical scavenging and metal reduction tests were performed to determine the antioxidant activity of the plant and the results were compared with Trolox. It was understood that the antioxidant potential of the plant was lower than Trolox. The results from biological abilities, molecular docking of catechin hydrate as abundant phenolic compounds in quince leaves extract to be an inhibitor candidate for AChE, BChE and ?-glycosidase.Öğe Sustainable Food and Agriculture Production: Reducing Food Waste through Technological Advancements and Assessing Its Economic Impact(Nan Yang Academy of Sciences Pte. Ltd, 2024) Öztuna Taner, ÖznurThe food waste (FW) is a widespread and persistent concern that has substantial environmental, social, and economic consequences. This study addresses the intricate relationship among sustainable food production, technological innovation, and the imperative to reduce FW, analyzing the entire food supply chain from production to consumption to identify key points where waste occurs. The potential of developing technologies is evaluated to induce substantial transformations. The study elucidates how precision agriculture, smart packaging, blockchain, artificial intelligence, and consumer-centric apps can transform food systems through a comprehensive assessment of literature and case studies. Challenges, opportunities, and future research directions are comprehensively discussed, emphasizing the need for collaborative, multi-stakeholder approaches to achieve a sustainable and waste-conscious food future.Öğe Enhancement of the energy and exergy analysis capabilities of the yoghurt process: a case study of the dairy industry(Frontiers Media SA, 2024) Öztuna Taner, ÖznurThis study provides a comprehensive analysis of the thermal and exergy characteristics of a dairy plant that produces yoghurt. This study aims to perform a comprehensive analysis of the thermal and exergy aspects of a dairy facility that produces yoghurt. This study also seeks to improve the accuracy of the results by evaluating the reliability of the energy and production data. A comprehensive analysis of energy and exergy is utilized to enhance the yoghurt production process. Moreover, the Grassmann-Sankey diagram is employed to produce a map of energy density. The process’s energy and exergy efficiencies were assessed by taking into account the enhancements and alterations made in addition to the existing implementations. Analysis of the yoghurt production process revealed that the total energy input was 113.9 [kW], the total energy output was 72.05 kW as well and the energy efficiency was 63.3%. The exergy input and output for the yoghurt production process were calculated to be 48.95 [kW] and 29.77 [kW], and the exergy efficiency was determined to be 60.8%. This study is expected to promote the growth of livestock and agriculture in the energy sector, and is forecasted to act as a catalyst for future research. This study, which is the first of its kind in the region and is expected to stimulate further research, reveals that improving energy efficiency and conservation in the production of yoghurt products enhances the factory’s overall energy efficiency.Öğe Chemical composition and nutrient profiles of nine red macroalgae species(BioMed Central Ltd, 2024) Yücetepe, Aysun; Kırkın, Celale; Ayar, Eda Nur; Soylukan, Caner; Dikici, Emrah; Özçelik, Beraat; Okudan, Emine ŞükranNine red macroalgae (Amphiroa rigida, Gracilaria bursa-pastoris, Gracilaria gracilis, Grateloupia torture, Jania rubens, Laurencia obtusa, Laurencia pyramidalis, Liagora viscida, and Pterocladiella capillaries) were collected from coastal waters of Türkiye, and their proximate, fatty acid, soluble carbohydrate, and mineral profiles were investigated in the present study. According to the results, the crude protein content of the samples was between 4% and 23.8%, and four of the samples (G. turuturu, L. obtusa, L. pyramidalis, and P. capillacea) contained more than 10% protein. The crude lipid content of all the samples was below 1.6%, and the total carbohydrate content was between 38.3% and 76.9%. The macroalgae samples were generally richer in saturated fatty acids, palmitic acid being the most abundant, whereas G. gracilis had the highest content of unsaturated fatty acids (55.8%). All samples exhibited high contents of myo-inositol or glucose. Also, the samples generally had a good composition of minerals. Still, the heavy metal (i.e., Pb and Cd) content of Gracilaria gracilis was higher (59.6 µg/kg, P < 0.05) than those of the other algae samples. This study provides valuable insight into the chemical composition and fatty acid, mineral, and soluble carbohydrate profiles of Amphiroa rigida, Gracilaria bursa-pastoris, Gracilaria gracilis, Grateloupia turuturu, Jania rubens, Laurencia obtusa, Laurencia pyramidalis, Liagora viscida, and Pterocladiella capillacea from Türkiye.Öğe Dairy factory milk product processing and sustainable of the shelf-life extension with artificial intelligence: a model study(Frontiers Media SA, 2024) Öztuna Taner, Öznur; Çolak, Andaç BaturThis study models milk product processing and sustainable of the shelf-life extension in a dairy factory using artificial intelligence. The Cappadocia dairy factory was used to study chemical processes and computational system modeling and simulation. Levenberg–Marquardt algorithm was used to create an artificial neural network model from real-time data. An AI-based method utilizing a Multilayer Perceptron (MLP) Artificial Neural Network (ANN) model was employed to precisely analyze productivity data in dairy factories. There are 9 product types and production quantities used as input parameters, and 90 datasets of actual dairy products used as output values. The model was trained using the Levenberg–Marquardt algorithm on 62 datasets for training, 14 for validation, and 14 for testing. The accuracy of the model is affected by the optimal data segmentation. The model showed how AI algorithms can improve processes and industrial production by increasing dairy production efficiency from 20 to 40%. Model efficiency values were compared to observed values to determine prediction accuracy. Model mean squared error was 4.02E-06, and coefficient of determination was 0.99984. Model efficiency predictions and observed values differed by ?0.04% on average. This study investigated using artificial intelligence to optimize salvage processes and systems to increase energy efficiency and reduce environmental impact. The results show that a neural network model trained with real data can predict dairy plant productivity.Öğe Green Synthesis of Silver Nanoparticles Using Leaf Extract of Calluna vulgaris: Characterizations, Properties, and Photocatalytic Activities(North Carolina State University, 2024) Akalın, Gülen OytunGreen synthesis of silver nanoparticles was carried out using leaf extract from Calluna vulgaris. The formation of nanoparticles was confirmed through the emergence of a surface plasmon resonance band in ultraviolet-visible spectroscopy. The characterization conducted using various microscopic techniques revealed that the nanoparticles mostly ranged in size from approximately 20 to 70 nm. Analysis, including Fourier transform infrared spectrometry, X-ray diffraction, and energy-dispersive X-ray spectroscopy, confirmed the chemical, crystalline structure, and presence of silver, respectively. The synthesized nanoparticles exhibited notable stability with an average zeta potential of-23.1 ± 0.6 mV. Evaluation of their antibacterial activity against Staphylococcus aureus and Escherichia coli demonstrated significant efficacy with diameters of inhibition zones measuring 10.23 ± 0.54 mm and 15.38 ± 0.32 mm, respectively. Additionally, the nanoparticles displayed a remarkable inhibition of approximately 88% against E. coli biofilm formation at a concentration of 100 ?g/mL. They also exhibited unique photocatalytic performances. This research contributes to the literature in this field by producing new silver nanoparticles with cost-effectiveness, stability, antibacterial, antioxidant, antibiofilm, and photocatalytic properties, while using a previously untapped plant extract for this purpose.Öğe Preparation and Properties of Novel Mucilage Composite Films Reinforced with Polydimethylsiloxane(Wiley-VCH, 2024) Bilican, İsmailRecently, there is an increasing interest in research on biodegradable, non-toxic, and high-strength biomaterials that can replace plastics, especially in the food industry. In this study, mucilage obtained from Linum usitatissimum seeds is used to develop a natural biodegradable biomaterial by reinforcing it with different concentrations of polydimethylsiloxane (PDMS). The biomaterials produced in the form of films are thoroughly investigated in terms of physicochemical (Fourier transform infrared spectroscopy, thermogravimetric analysis, scanning electron microscopy (SEM), energy dispersive X-ray spectrum (EDX), atomic force microscopy (AFM), contact angle, and mechanical), biodegradable (in soil and water), and antibacterial properties. SEM-EDX and AFM demonstrate the homogeneous distribution of PDMS throughout the mucilage matrix. The incorporation of PDMS improves the water solubility of the mucilage composite films, thereby enhancing their strength. It also imparts hydrophobic characteristics to the composite films. Thus, PDMS ensures the high barrier property of the composite films against water vapor. Furthermore, the addition of PDMS increases the antimicrobial properties of the mucilage composite films. The obtained results indicate that the first-time produced mucilage-PDMS composite films can serve as an alternative product for food packaging applications.Öğe Sports Performance Based on Food Nutrition: A Scenario Study(Asian Exercise and Sport Science Association, 2023) Öztuna Taner, ÖznurThis study presents sports performance based on food nutrition. The study aims to increase athletes' power and anaerobic fatigue by eating enough food nutrition to use sports exercise on a cycle ergometer by a scenario study. Objectives. The cycle ergometer model and simulation of energy-power is impacted by nutrition and movement as the study linked energy and power (the athlete scenario). Methods. This study conducted a theoretical study using 21 scenario athlete weights and a cycle ergometer device. It focused on athlete strength and anaerobic fatigue using flywheel resistance. The study demonstrated reliability and mathematical modeling of scenario data. This study was based on SPSS 28.0 for data analysis and evaluation (one-way ANOVA, spectral analysis, autocorrelation function, and T-Test), assessing the reliability of scenario data using regression analysis. Results. The modeling showed that the scenario athletes with 21 different weights had an anaerobic fatigue efficiency greater than 80% and anaerobic power capacities between 10.2 [kW] and 16.7 [kW]. Conclusion. The athletes' anaerobic capacity and fatigue increased with weight, but their efficiency (capacity) remained the same. As a result, ATP (Adenosine Triphosphate) is produced and used by the body, which enhances performance. This study demonstrates how the athlete's social economic environment and movement patterns impact power-energy.Öğe Energy and production analysis of a dairy milk factory: A case of study(Yildiz Technical University, 2023) Öztuna Taner, ÖznurThis study illustrates a factory’s production efficiency by demonstrating its energy efficiency in the dairy milk industry. Determining the thermal energy to save energy enhances the profitability of the factory. The aim of this study is to conduct a thermal energy and production analysis of a dairy milk factory based on annual production. This study intends to make the conclusions more realistic by using production and energy data dependability analysis. The overall power consumption for the thermal and electric energy processes was found to be as 180,520 [W]. The target-specific energy consumption value was computed for Case 1 as 6,352.14 [MJ/t], for Case 2 as 5,898.67 [MJ/t], and for Case 3 as 5,445.21 [MJ/t]. The annual thermal (steam boiler) and electrical energy expenditures were obtained, with 315.87 [kW] of thermal (steam) energy and 80.98 [kW] of electrical energy. The total thermal and electrical energy reached 396.85 [kW]. Despite the factory’s expenditure on thermal and electrical energy, the energy efficiency was determined to be as 45.5%. The input energy was obtained to be 374.24 [kW] in Case 1, 356.33 [kW] in Case 2, and 342.08 [kW] in Case 3. The energy efficiency was calculated as 48.2 [%] for Case 1, 50.7 [%] for Case 2, and 52.8 [%] for Case 3. This study, which is expected to inspire future research, is also likely to assist livestock and agriculture in the energy field. The novelty of this study is that optimizing product efficiency and energy consumption in the production of milk and dairy products positively increases the energy efficiency of factories.Öğe Determination of Antioxidant Activity of The Leaves of Hawthorn (Crataegus Monogyna)(Iğdır Üniversitesi, 2023) Dikici, Emrah; Köksal, EkremThis study was carried out to make decision the antioxidant activity of the leaves of hawthorn (Crataegus monogyna), which is a natural source of antioxidants. For this purpose, the leaves of hawthorn were collected and dried, and an ethanol extract was prepared. Total antioxidant activity (with respect to the ferric thiocyanate method), ion reduction capacity of Cu2+ (copper method), and Fe3+ (potassium ferricyanide reduction method) were determined on the prepared ethanol extracts. Additionally, scavenging activity of DPPH (1,1-diphenyl-2-picrylhydrazyl) and determination of the total phenolic-flavonoid compound content were carry out. The extracts obtained from Hawthorn (Crataegus monogyna) leaves were found to inhibit lipid peroxidation (of linoleic acid emulsion) by 40.9%. This inhibition occurred at a concentration of 10 µg/mL of the extracts. At the similar concentration, BHT exhibited 68.3% inhibition, while trolox exhibited 29.9% inhibition. Hawthorn (Crataegus monogyna), which was found to have a higher total phenolic content than trolox, exhibited significant DPPH scavenging and metal reduction activities. During the investigation of the antioxidant activity of the ethanol extract obtained from Crataegus monogyna, ?-tocopherol, its water-soluble analogue trolox and BHT (butylated hydroxytoluene) were utilized as reference antioxidant compounds.Öğe Vacuum freeze dryer technology for extending the shelf life of food and protecting the environment: a scenario study of the energy efficiency(SpringerLink, 2024) Öztuna Taner, ÖznurThis study focused into vacuum freeze dryer technology for increasing food shelf life in a drying food technology. The determinants of energy consumption increase as the energy density of food production and storage increases. Reducing the amount of energy used for drying, freezing, chilling, refrigeration, and air conditioning is becoming more important. The objective of this study was to extend food's shelf life utilizing creative and novel technical approaches, such as vacuum freeze-drying's energy-efficient process. Despite being a part of this investigation, the vacuum freeze drier was created using environmentally benign energy sources. To minimize the carbon footprint of food preservation, it is essential to use eco-friendly energy sources in chilling storage. According to the first law of thermodynamics, the energy efficiency at 1 atm pressure and 25 [°C] temperature (neglecting potential and kinetic energies) in the dead state is calculated under thermal equilibrium conditions. In this study, the energy efficiency was shown according to 5 different scenarios. The results of energy efficiencies are as follows: ?1 is from 14.3 to 21.4%, ?2 is from 20.7 to 31.0%, ?3 is from 27.3 to 40.9%, ?4 is from 32.1 to 48.1%, and ?5 is from 34.6 to 51.9%, respectively. This analysis demonstrates that the energy efficiency improved from 12 to 18 h. In this study, optimizations with scenarios were employed considering vacuum freeze-drying technology in the plant with sustainable energy sources can considerably improve food shelf life while limiting our environmental impact.Öğe An inclusive physico-chemical perspective on food waste: Textural and morphological structure(Elsevier Ltd, 2023) Çelebi, Hakan; Bahadır, Tolga; Bilican, IsmailIn recent years, thanks to their advantages such as low cost, easy availability, reusability as adsorbent materials, and high metal ion removal capacities in aqueous solutions, food waste attract the attention of researchers. In this study, almond shell (AS), peanut shell (PS), walnut shell (WS), and pumpkin seed hull (PSH) were characterized using analytical methods such as Fourier Transform Infrared (FTIR) Spectroscopy, Scanning Electron Microscope (SEM)/Energy dispersed X-ray (EDX), and Brunauer–Emmett–Teller (BET). The surface morphologies, functional groups, surface area, and pore size of AS, PS, WS, and PSH were evaluated together, and their specific properties were revealed. According to EDX analysis, %C and %O content is high for all biosorbents. Using FTIR analysis, carboxylic (–COOH), amines (N–H) and hydroxyl groups (–OH) in the structure of AS, WS, PS, and PSH were determined. Pore morphologies were determined as mesopore (250 nm) for AS, PS, WS, and PSH. Surface areas for AS, PS, WS and PSH were determined as 6.20, 4.12, 3.98 and 2.74 m2/g, respectively. In addition, using the Principal Component Analysis (PCA) model, the effect levels of AS, PS, WS, and PSH on the adsorption process were determined by FTIR and EDX data sets. With the increasing interest in environmental preservation, it is anticipated that low-cost food waste-based biosorbents will be utilized in various applications in the future.Öğe Effective Removal of Cationic Dyes from Aqueous Solutions by Using Black Cumin (Nigella sativa) Seed Pulp and Biochar(North Carolina State University, 2023) Şişmanoğlu, Sedef; Akalın, Mehmet Kuddusi; Akalın, Gülen Oytun; Topak, FatımaBlack cumin seed pulp (C), as well as biochar (CC) produced via pyrolysis of black cumin seed pulp were used to remove methylene violet 2B (MV) and basic yellow 28 (BY28) from aqueous solution. Adsorption isotherms and kinetics were applied at 10, 25, and 35 °C. The adsorption of methylene violet 2B and basic yellow 28 on the black cumin seed pulp and biochar surface was exothermic; the heat of adsorption values were lower than 0. The adsorption capacities of BY28-C, BY28-CC, MV-C, and MV-CC were 212.8, 625, 164, and 909 mg g-1 at 25 °C, respectively. The adsorption of black cumin seed pulp and biochar data were examined with the Freundlich, Langmuir, Temkin, Dubinin-Radushkevich (D-R), and Flory-Huggins (F-H) isotherm models. The kinetics of the adsorption were fitted to the pseudo first-order and pseudo second order equations. The pseudo second order equation gave a better fit than the pseudo first-order equation.Öğe Alginate/carboxymethylcellulose-based hydrogels as pH-sensitive drug delivery systems: facile production with enhanced degradation, thermal and mechanical properties(Springer Science and Business Media Deutschland GmbH, 2023) Akalın, Gülen OytunpH-Sensitive alginate (ALG)/sodium carboxymethylcellulose (CMC) hydrogels were synthesized using a novel technique to utilize as a drug carrier in this study. The characterization of hydrogels was performed using FTIR (Fourier-transformed infrared spectroscopy), SEM(scanning electron microscopy), TGA (thermogravimetric analysis), DSC (differential scanning calorimetry), gel content and mechanical tests. The last technique is new and it is compared with the most well-known ionic crosslinking method to investigate the effectiveness of the technique. Gel content, degradation and thermal and mechanical stabilities were found to be higher. Swelling and degradation behaviors of hydrogels were studied in simulating gastric juice of pH 1.2 or simulating intestinal fluid of pH 6.8 and simulating colon fluid of pH 7.4 at 37 °C. The maximum swelling degree was observed at pH 7.4, and the minimum swelling degree was obtained at pH 1.2. An Anti-arrhythmics drug, propranolol hydrochloride (PPN), was loaded onto the obtained hydrogels as a model drug. Encapsulation efficiency (%) and drug loading amount (g/g) of ALG/CMC hydrogels synthesized by a new technique were found to be 61–68.4% and 0.152–0.171 g/g, respectively. The values of initial burst release at 15 min (%), drug released at 7 h (%) and equilibrium drug release were researched. Different kinetic model parameters (zero-order, first-order, Higuchi, and Korsmeyer–Peppas models) were calculated to investigate the drug release mechanism. The engineered hydrogels displayed controlled swelling capacity, cavitary surfaces, more porosity, high degradation resistance, gel content, thermal and mechanical properties and controlled drug release. These findings suggest that hydrogels synthesized by this new technique may be useful as a drug delivery system.Öğe Evaluation of biological (feed, water), seasonal, and geological factors affecting the heavy metal content of raw milk(Academic Press Inc., 2023) Özbay, Sena; Dikici, Emrah; Soylukan, CanerIn volcanic regions worldwide, soil and water can be contaminated with heavy metals. Aksaray province is also an important region in this respect. Because this city is located around Hasandağı, an extinct volcanic mountain. In addition, the city is also an important dairy center. In this regard, evaluating the milk produced in Aksaray in terms of heavy metal contamination and studying the effect of feed and water on this contamination is essential. For this purpose, feed, water, and milk samples from 7 milk producers determined in Aksaray province were collected in 3 different seasons within six months. The presence and levels of arsenic (As), aluminum (Al), nickel (Ni), cadmium (Cd), and lead (Pb) were determined by ICP-MS analysis of the 126 samples obtained. The study found varying levels of heavy metals in feed, water, and milk. It was also observed that milk contained considerably lower quantities of metals and metalloids than feed and water. In addition, it has been determined that the distance to Hasandağı does not affect the trace element levels in water, milk, and feed, but there is a significant relationship between seasonal changes and trace elements in the samples. According to the analysis results, the highest level is the feed's aluminum level (298,290.1 µg/kg). However, the aluminum level in milk remained well below this level (96.15 µg/kg). It was determined that the cadmium level in milk reached the highest level in spring (average 0.06 µg/kg), whereas lead levels reached the highest level in summer (average 2.14 µg/kg). On the other hand, the arsenic level showed a relatively small change according to the distance to the volcanic region. The average arsenic level in milk from regions near the volcanic area was measured as 1.01 µg/kg. In remote areas, this amount was measured as 0.94 µg/kg, Furthermore, the highest heavy metal level in the milk was 182.08 µg/kg for nickel during the summer months in the study.Öğe Self-Assembled Short Peptide Nanostructures: ‘’Dipeptides’’(Kırgızistan-Türkiye Manas Üniversitesi, 2023) Dikici, Emrah; Önal Acet, Burcu; Gök, Tuba; Acet, Ömür; Odabaşı, MehmetDipeptides are short peptide molecules formed by the peptide bond between two amino acids, and they play significant roles in various biological processes (such as protein synthesis, nutrient absorption, cellular signaling, immune response). Short peptides have a prominent place in the design of self-assembling materials. In particular, dipeptides have gained considerable attention in the field of biotechnology as a type of self-organizing nanostructure due to their low cost, simplicity of synthesis, biocompatibility, and tunability of functionality. However, there is limited knowledge about peptide and protein-based nanostructures in the literature. Therefore, more information is needed on dipeptide nanostructures, especially in terms of their potential applications for biomedical purposes. This review focuses on dipeptide nanostructures, particularly their potential uses in biomedical applications, and provides a broader perspective on the advantages, challenges, synthesis, interactions, and applications of these nanostructures.Öğe A rational approach for 3D recognition and removal of L-asparagine via molecularly imprinted membranes(Elsevier B.V., 2023) Acet, Ömür; Ali Noma, Samir Abbas; Önal Acet, Burcu; Dikici, Emrah; Osman, Bilgen; Odabaşı, MehmetIn this study, a L-asparagine (L-Asn) imprinted membranes (L-Asn-MIPs) were synthesized via molecular imprinting for selective and efficient removal of L-Asn. The L-Asn-MIP membrane was prepared by using acrylamide (AAm) and hydroxyethyl methacrylate (HEMA) as a functional monomer and a comonomer, respectively. The membrane was characterized by scanning electron microscopy (SEM) and Fourier Transform infrared spectroscopy (FTIR). The L-Asn adsorption capacity of the membrane was investigated in detail. The maximum L-Asn adsorption capacity was determined as 408.2 mg/g at pH: 7.2, 24 °C. Determination of L-Asn binding behaviors of L-Asn-MIPs also shown with Scatchard analyses. The effect of pH on L-Asn adsorption onto the membrane and also the selectivity and reusability of the L-Asn-MIPs for L-Asn adsorption were determined through L-asparaginase (L-ASNase) enzyme activity measurements. The selectivity of the membrane was investigated by using two different ternary mixtures; L-glycine (L-Gly)/L-histidine (L-His)/L-Asn and L-tyrosin (L-Tyr)/L-cystein(L-Cys)/L-Asn. The obtained results showed that the L-Asn-MIP membranes have a high selectivity towards L-Asn.Öğe “Lab-on-pol” colormatic sensor platforms: Melamine detection with color change on melamine imprinted membranes(Elsevier Inc., 2023) Dikici, Emrah; Önal Acet, Burcu; Acet, Ömür; Odabaşı, MehmetThere is an urgent need to improve a specific, equipment-free and user friendly technique for detecting melamine in food samples. Here, melamine imprinted polymeric membranes were synthesized, and tested for selectivity in aqueous solutions against cyromazine used as competitor agent, and real milk samples spiked with melamine. Scanning electron microscope, atomic force microscopy, energy-dispersive X-ray and optical profilometer devices were used for characterization. Fe+3 ions were used as marker to obtain color change based on melamine concentration. The color intensity on MIP membranes was monitored by means of a color analysis application (Image J software) via a smartphone. Some obtained results as fallows: Melamine binding to 3D cavities of membrane came true in about 20 min. The linear regression plot showed a correlation coefficient (R2) of 0.995 in the range of 10 ?M-50 ?M according to Beer Lambert's law. A low concentration of melamine, (e.g., 10 µM) was determined in raw milk. Melamine imprinted polymeric membranes showed 7.575 times more sensitivity for melamine than cyromazine. Limit of detection (LOD) and limit of quantification (LOQ) were computed as 9.9 µM and 30.2 µM, respectively. Here, a new kind of smart polymer was designed, and successfully applied for the easy, portable and on-site colorimetric analysis via imprinted polymers, and named as “lab-on-pol”system. HPLC analysis method was also used to validate this new analysis method.Öğe Determination of volatile N-nitrosamines formed in salami cooked by different processes(Academic Press Inc., 2022) Özbay, SenaThe purpose of the study is to determine the amount of volatile N-nitrosamine (VNA) found in different brands, ingredients, and types of salami. In addition, it is also aimed to understand the interactions between the types and levels of VNA formed as a result of cooking salami with different cooking techniques (frying, boiling, microwave). For this purpose, salami samples from 20 different brands have been collected and cooked with three different cooking techniques (frying, boiling, microwave) and analyzed by GC-MS (Gas chromatography-mass spectrometry). NDBA was detected in almost all (98 %) of all salami samples examined, followed by NDPA (95 %) and NPYR (94 %). The less common VNA derivative compared to the others was determined as NMEA (63 %). When all the cooked samples were evaluated, the total VNA level was determined between 57.77 and 8.45 ppb. As a result of the research, different levels of VNA formation were detected in each salami sample. In addition, NDMA, NDPA, NPIP and NDBA levels of different brands of salami were found to vary significantly. Moreover, cooking was found as the most important factor in VNA formation and level. Additionally, the cooking process significantly affected the levels of all nitrosamine derivatives except NDPA.
