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Hazelnut by-products as a valuable resource: Lipid peroxidation inhibition effect, bioaccessibility and antidiabetic properties
(Elsevier Ltd, 2025) Okumuş, Emine; Temiz, Mehmet Ali
The aim of this study is to determine the chemical and molecular properties of hazelnut by-products, to measure the bioaccessibility values of phenolic compounds found in the structure of these wastes and to reveal their antidiabetic and lipid peroxidation (LPO) inhibition effects. The highest moisture and protein content were found in skin samples with 6.33% and 7.70%, respectively. The predominant fatty acid in hazelnut skin is oleic acid, which constitutes 78.65% of the total fatty acid composition. The highest antioxidant activity value was measured in the shell with an IC50 value of 19.08 mg/mL. The sample with the highest content of gallic acid and protocatechuic acid content was the skin extract. The dominant phenolic component in the shell and husk samples was kaempferol, while in the skin sample it was rutin. Shell bioaccessibility was found to be much higher for o-coumaric acid (45.83%), rutin (49.25%) and kaempferol (46.32%) components. The bioaccessibility of the shell sample in total phenolic concentration was measured as 45.87%. The highest LPO inhibition value belonged to the shell sample with an IC50 of 4.50 mg/mL, while the lowest value belonged to the husk sample with an IC50 value of 25.03 mg/mL. The highest antidiabetic effect was observed in the shell sample with values of 3.55 mg/mL and 25.44 mg/mL for α-amylase and α-glucosidase inhibition, respectively. The highest recovery belonged to 4-Hydroxybenzoic acid in the skin sample. As a result, it was concluded that hazelnut by-products, especially the shell, exhibit high antioxidant effects, have antidiabetic and LPO inhibition properties thanks to their bioactive components and high bioaccessibility values. Thus, they have valuable usage opportunities in the fields of food, pharmacology and medicine. © 2025 Elsevier Ltd
A "on-off" fluorescent sensor based on coumarin-furoic hydrazide for recognition of fe3+: drinking water, test strip applications and dft calculations
(Springer/Plenum Publishers, 2025) Karagöz, Abdurrahman; Savran, Tahir; Yılmaz, İbrahim
A coumarin based fluorescent probe (E)-N'-((7-hydroxy-2-oxo-2H-chromon-3-yl)methylene)furan-2-carbohydrazide (CFHZ) was synthesized for the detection of Fe3+ and its characterizations were carried out using spectroscopic methods such as FT-IR, mass spectrometry1H-NMR, 13C-NMR. The novel probe CFHZ showed a highly selective and sensitive "turn-off" response to Fe3+ ion without any interference from other analytes. Strong fuorescence quenching phenomena of the CFHZ were observed in EtOH:H2O (99/1, v/v) detection system (lambda em = 470 nm) upon the additions of Fe3+. The binding stoichiometry between CFHZ and Fe3+ was determined by Job's method, FT-IR and MALDI TOF-MS and found to be 2:1. Also, the binding constant was determined to be 1.82 x 105 M-1 and the limits of detection for the analysis of Fe3+ was measured as 25.7 nM. Besides, experimental applications were carried out for real-time monitoring of Fe3+ in water samples using developed sensor. Additionally, fluorescence imaging experiments for Fe3+ detection of CFHZ probe on test papers were successfully performed.
Macroalgal (ulva compressa) silver nanoparticles: their characterization, cytotoxicity, and antibacterial applications
(Central Fisheries Research Inst, 2024) Armağan, Esra; Keskinateş, Mukaddes; Gümüş, Numan Emre; Aydın, Ziya; Yılmaz, Bahar; Bayrakcı, Mevlüt
In this study, an extract of Ulva compressa (UC), a green macroalgae, was used to synthesize biogenic silver nanoparticles (AgNPs). The formation of nanoparticles (NPs) was evaluated and confirmed by using ultraviolet-visible (UV-VIS) spectroscopy, Fourier transform infrared spectroscopy (FT-IR), X-ray diffraction (XRD), and transmission electron microscopy (TEM) analyses. UV-VIS spectra showing absorption peaks at 450 nm confirmed the formation of AgNPs. The particles were crystalline in nature according to the XRD pattern. AgNPs formation was proved by the FT-IR spectrum of UC. TEM image showed that the average particle size was 4.55 nm. The antimicrobial and anticarcinogenic activity was evaluated for the synthesized AgNPs. AgNPs obtained from algae demonstrated antimicrobial activity against all bacteria including B. subtilis, E. faecalis, S. mutans, E. coli, S. aureus, and S. pyogenes. The NPs were shown to have anticarcinogenic activity on HEK 293, MCF-7, and HeLa (reducing viability by 25.42%, 46.42%, and 62.42%, respectively) cell cultures. These findings indicate that AgNPs can be useful medicinal compounds. Green synthesized NPs can be developed and utilized as anticancer agents in the treatment of various types of cancer, as well as their antimicrobial effects can be utilized to ensure the long-term sustainability of food in this study.
Enhancing microalgae classification accuracy in marine ecosystems through convolutional neural networks and support vector machines
(Pergamon-Elsevier Science Ltd, 2024) Sönmez, Mesut Ersin; Gümüş, Numan Emre; Eczacıoğlu, Numan; Develi, Elif Eker; Yücel, Kamile; Yıldız Hüseyin Bekir
Accurately classifying microalgae species is vital for monitoring marine ecosystems and managing the emergence of marine mucilage, which is crucial for monitoring mucilage phenomena in marine environments. Traditional methods have been inadequate due to time-consuming processes and the need for expert knowledge. The purpose of this article is to employ convolutional neural networks (CNNs) and support vector machines (SVMs) to improve classification accuracy and efficiency. By employing advanced computational techniques, including MobileNet and GoogleNet models, alongside SVM classification, the study demonstrates significant advancements over conventional identification methods. In the classification of a dataset consisting of 7820 images using four different SVM kernel functions, the linear kernel achieved the highest success rate at 98.79 %. It is followed by the RBF kernel at 98.73 %, the polynomial kernel at 97.84 %, and the sigmoid kernel at 97.20 %. This research not only provides a methodological framework for future studies in marine biodiversity monitoring but also highlights the potential for real-time applications in ecological conservation and understanding mucilage dynamics amidst climate change and environmental pollution.
Selective chromo-fluorogenic chemoprobe for nm al3+ recognition: experimental and living-cell applications
(Springer/Plenum Publishers, 2024) Genç, Hayriye Nevin; Yaşar, Özlem Güçtekin; Boran, Tuğçe; Elmas, Şükriye Nihan Karuk; Arslan, Fatma Nur; Yılmaz, İbrahim; Sirit, Abdülkadir
A rhodamine based chemoprobe BESN was engineered and employed as a selective ''OFF-ON'' chromo-fluorogenic sensor for Al3+ in H2O:MeOH (1:9, v:v). Notable changes in the absorption and emission spectra of BESN were clearly detectable upon the addition of Al3+. Sensitivity and binding mechanism studies demonstrated a good sensing performance of BESN with nanomolar detection limit (130 nM), and it was found to be highly selective towards interfering metal ions. Besides, the binding constant between BESN and Al3+ was found to be 3.19 x 10(3) M-1. Then, the validation study of BESN for Al3+ was performed based on significant analytical parameters and statistical tests. The binding of Al3+ with BESN (1:1) was probed via infrared, high-resolution mass and emission (Job's plot) spectroscopy measurements. The sensing performance of BESN could make it ideal chemosensor for real applications including vegetable, tuna fish and water samples, also for Smartphone and test-kit applications. The recovery values of the BESN to Al3+ were estimated within a range from 95.13% to 105.30% for water, 94.63% to 109.62% for tuna fish and 94.80% to 109.80% for vegetable samples. Additionally, the BESN has very low cytotoxicity and was triumphantly utilized for the recognition of Al3+ in living-cells.
Changes within the Daytime of Essential Oil Content and Composition of Zahter (Thymbra spicata L.) Grown in Ermenek Conditions
(2019) Maral, Hasan; Kırıcı, Saliha
Thymbra spicata var. spicata is known as “Zahter ”, “Sater” or “Karabaş thyme in the Southeastern Anatolia Region of Turkey and leaves and flowers are consumed as spices and tea, while young shoots are consumed as salads.This study was carried out to determine the change in essential oil content and chemical compositionduring the daytime of the Thymbra spicata plant in Ermenek district of Karaman.In order to determine the diurnal variation, the harvest was done at 5 different hours during the daytime (6:00, 9:00, 12:00, 15:00 and 18:00) in the flowering period. The harvested\rplants were dried in the shade and the essential oil contents were determined by Clevenger apparatus by hydro distillation and analyzed by GC-MS. The highest content of essential oil was obtained at 18.00 hours with 2.96% and the lowest one’s was obtained at 12.00 hours with 2.20%.The main components of the essential oil were determined as carvacrol (23.29% - 39.89%), thymol (16.24% -\r21.52%) and ?-terpinene (18.01% - 20.90%).
Biochemical And Molecular Characterization Of Bread Wheat Genotypes Under Drought Stress: İmplications For Antioxidant Defense Mechanisms And Genomic Analysis
(University of Ljubljana, 2024) Eczacıoğlu, Numan; Aksoy, Begüm Terzi; Ateş Sönmezoğlu, Özlem ; Ulusu, Yakup
Plants face abiotic stresses like drought, salinity, and high temperature, which adversely affect growth and induce physiological and metabolic changes. Drought is a complex stress controlled by many genes, requiring investigation through molecular markers and biochemical characterization in wheat genotypes. This study involved eight bread wheat cultivars and two controls: drought-tolerant ‘Gerek-79’ and drought-sensitive ‘Sultan-95’. These were grown for 40 days and then subjected to 10 days of drought stress. Antioxidants and antioxidant enzyme activities, which neutralize ROS, are key resistance mechanisms against oxidative stress. Levels of polyphenol oxidase (PPO), peroxidase (POD), ascorbate peroxidase (APX), and catalase (CAT) were measured. Plant responses to stress included changes in photosynthetic pigments, total proteins, hydrogen peroxide, lipid peroxidation (MDA), and proline levels. POD showed the highest change in enzyme activity, while PPO was least affected. Chlorophyll b levels increased under stress across all varieties. Notably, proline levels, an abiotic stress marker, significantly rose by the 10th day of drought. Additionally, wheat genotypes were analyzed using drought-related SSR markers (Xwmc 89, Xwmc 118, Xwmc 304, Xgwm 337). This allowed evaluation of the impact of molecular characterization on biochemical changes under drought stress. © 2024 University of Ljubljana. All rights reserved.
A comparison of extraction methods for preparation of glucosinolate-containing extracts from brassica juncea antagonistic toward ditylenchus dipsaci
(Brill Academic Publishers, 2024) Temiz, Mehmet A.; Aksay, Gamze; Özcan, Ali; Yavuzaslanoğlu, Elif
The stem and bulb nematode, a globally distributed pest, primarily affects onions and garlic, causing significant yield losses. Chemical treatments are a practical and effective method for controlling plant-parasitic nematodes to protect high-value crops. However, to minimise environmental damage, chemicals of natural origin need to be investigated. Brown mustard (Brassica juncea) plant is an annual plant in the Brassicaceae family, which is rich in bioactive compounds called glucosinolates. These bioactive compounds play a major role in the defence of Brassica plants against biotic stress factors in nature. Based on this point, efforts to develop plant protection products from the brown mustard plant are ongoing. In this study, the most suitable pre-extraction and extraction conditions were determined to ensure the maximum preservation of glucosinolate content and biological activity, to process brown mustard on an industrial scale. For this purpose, steam treatment was applied before extraction at 3 bar (=3 × 105 Pa) pressure for 1 and 3 min. Four different temperatures (room temperature, 40, 55 and 70°C) and two different methanol concentrations (70% and 80%) were tested to optimise glucosinolates extraction from brown mustard. It was found that sinigrin was the most abundant glucosinolate, with extraction yields 1184.4 ± 14.4 mg kg-1 at 55°C for 3 min, and 2624.2 ± 98.5 mg kg-1 at 70°C/70% MeOH for 1 min. However, nematode immobility was higher at 55°C/70% MeOH for 3 min. It was determined that the application of hot steam for 3 min at 3 bar pressure as a pre-extraction process provided optimal conditions for methanolic extraction. The results may contribute significantly to the development of potential plant protection products with further studies. © MEHMET A. TEMIZ ET AL., 2024.
Zero Waste Applications For the Apple Processing Wastes: Recovery of Valuable Compounds by Supercritical CO2 and Wastewater Treatment by Advanced Oxidation
(Institution of Chemical Engineers, 2025) Argun, Mehmet Emin; Argun, Mustafa Şamil; Ates, Havva; Arslan, Fatma Nur; Çakmakcı, Özgür; Nas, Bilgehan; Tongur, Süheyla
This study has focused on the characterization, recovery and treatment of apple processing wastes, which are important in terms of sustainability and circular economy. Apple processing wastewater (AW) was noted for its acidity (pH 4.2), high chemical oxygen demand (COD) (114 g/L), total solids (TS; 13.5 %) and oil/grease content (16.5 g/L), as well as the presence of valuable fatty acids and phenolics. Total phenolic content (TPC), total flavonoids content (TFC) and antioxidant activity were determined in the wastewater as 1660 mg GAE/L, 421 mg QE/L and 2.1 mM TE, respectively. The extraction of phenolic compounds from AW and apple pomace (AP) using supercritical carbon dioxide (SC–CO2) extraction was investigated as a first step. The results indicate that SC–CO2 extraction is effective in recovering phenolic compounds from apple processing wastes. The extraction yields for AW and AP using SC–CO2 reached up to 76 % and 43 % of the extractable oils, respectively. Recovery efficiencies of the TPC were observed to be up to 3.8 % for AW and 11.4 % for AP. Furthermore, the phenolic and fatty acid profiles of extracts were also evaluated, indicating the recovery of valuable compounds such as quercetin, catechin, procyanidin B2, ?–6 and ?–9 fatty acids. In terms of wastewater treatment, the use of ozone oxidation (OO) and supercritical water oxidation (SCWO) for the removal of COD, suspended solids (SS), TPC and toxicity from AW were also investigated. The OO exhibited relatively low COD removal efficiency, while SCWO demonstrated high efficiency ranging from 84 % to 99.8 %. This study has revealed that while SCWO effectively removes COD, TPC, SS and color from fruit processing wastewater, OO demonstrates greater effectiveness in reducing toxicity in the Vibrio fischeri test. © 2024 The Institution of Chemical Engineers
Occurrence of microplastics and nanoplastics in terrestrial ecosystem and their toxicological impacts in plants
(Elsevier, 2024) Özcan, Ali; Eczacıoğlu, Numan; Aydın, Ziya
Materials that are plastic in nature have gained popularity worldwide thanks to a variety of applications, durability, and low cost. Different types of plastics have been vastly produced since the 1940s, and they are an essential part of our life since. Plastics pose a significant risk to ecosystem health, human health, and natural life due to their widespread use. Plastic kinds are categorized according to their size, such as micro/nanoplastics (M/N-Ps). These plastics pose more issues for living things, disrupting the natural order of things and contaminating the water, air, and soil. Plants that get exposed to M/N-Ps uptake them at high concentrations, causing their death and harming the food quantity and quality. This chapter of this book is split into three sections. The first section of the chapter will introduce the concept of M/N-Ps and their nature of existence in the environment. The section will include M/N-Ps occurrence due to decomposition in nature and secondary product release of industrial production. The second section of the chapter will discuss how these plastics interact with the soil media. This chapter will cover the effects on soil chemical properties, microbial community, and soil physical properties, which affect overall plant growth and health. The last chapter will include the interaction of M/N-Ps with terrestrial plants and organic pollutants. Due to their small size, M/N-Ps could be mobilized into plant vascular. © 2024 Elsevier Inc. All rights reserved.
A unified Framework of Response Surface Methodology and Coalescing of Firefly With Random Forest Algorithm for Enhancing Nano-Phytoremediation Efficiency of Chromium Via in Vitro Regenerated Aquatic Macrophyte Coontail (Ceratophyllum demersum L.)
(Springer, 2024) Ali, Seyid Amjad; Gümüş, Numan Emre; Aasim, Muhammad
Nano-phytoremediation is a novel green technique to remove toxic pollutants from the environment. In vitro regenerated Ceratophyllum demersum (L.) plants were exposed to different concentrations of chromium (Cr) and exposure times in the presence of titania nanoparticles (TiO2NPs). Response surface methodology was used for multiple statistical analyses like regression analysis and optimizing plots. The supplementation of NPs significantly impacted Cr in water and Cr removal (%), whereas NP × exposure time (T) statistically regulated all output parameters. The Firefly metaheuristic algorithm and the random forest (Firefly-RF) machine learning algorithms were coalesced to optimize hyperparameters, aiming to achieve the highest level of accuracy in predicted models. The R2 scores were recorded as 0.956 for Cr in water, 0.987 for Cr in the plant, 0.992 for bioconcentration factor (BCF), and 0.957 for Cr removal through the Firefly-RF model. The findings illustrated superior prediction performance from the random forest models when compared to the response surface methodology. The conclusion is drawn that metal-based nanoparticles (NPs) can effectively be utilized for nano-phytoremediation of heavy metals. This study has uncovered a promising outlook for the utilization of nanoparticles in nano-phytoremediation. This study is expected to pave the way for future research on the topic, facilitating further exploration of various nanoparticles and a thorough evaluation of their potential in aquatic ecosystems. Graphical Abstract: (Figure presented.) © The Author(s) 2024.
Lighting the future: Perovskite nanorods and their advances across applications
(Elsevier Ltd., 2024) Aftab, Sikandar; Li, Xin; Kabir, Fahmid; Akman, Erdi; Aslam, Muhammad; Pallavolu, Mohan Reddy
This in-depth analysis explores the many uses of perovskite nanorods (PNRs), which is a class of materials with remarkable optoelectronic characteristics that are produced by efficient synthesis methods. PNRs are remarkably versatile in various technological domains. The following are some of their most important applications. First, we have comprehensively described innovative/efficient manufacturing techniques that are used in order to produce high-quality properties PNRs materials. The high surface-to-volume ratio of PNRs and other optoelectronic characteristics are then useful in regards to raising solar cell efficiency. Furthermore, they are essential for light-emitting diodes (LEDs) and photodetectors (PDs), which help in order to enhance the performance in these applications. PNRs can be used in solid-state lighting by taking advantage of their special optoelectronic properties. PNRs are appropriate for various sensing applications due to their high surface-to-volume ratio, which makes advanced sensing capabilities possible. Moreover, PNRs offer advantages in non-volatile memory applications due to their resistive switching behavior, which supports resistive random-access memory (RRAM) devices. PNRs hold potential for quantum optics and communication developments in specific applications, such as polarized light detectors and nanolasers. Continuous investigations proactively tackle these matters by withstanding obstacles to stability and ecological worries, which enable PNRs to reach their maximum potential in various technological uses. The key to realizing the enormous potential of PNRs across a wide range of applications is simply to unlock their door.
Synergistic effects of energy level alignment and trap passivation via 3,4-dihydroxyphenethylamine hydrochloride for efficient and air-stable perovskite solar cells
(American Chemical Society, 2024) Mohammed, Mustafa K. A.; Abualsayed, Mohammad Ibrahim; Alshehri, Ali M.; Kumar, Anjan; Dehghanipour, Masoud; Akman, Erdi
Grain boundaries and surface defect states in perovskite films damage the charge transport mechanism by acting as nonradiative recombination centers, thus resulting in poor device performance and unsatisfactory long-term stability. For this aim, we added 3,4-dihydroxyphenethylamine hydrochloride (3,4-DpACl) as an effective additive to chlorobenzene antisolvent and used it during perovskite fabrication. The characterization results infer that the 3,4-DpACl material not only assists in forming a smoother perovskite film along with the reduction of residual lead iodide but also brings a passivation effect from the possible chemical interaction between the C═O of 3,4-DpACI molecules and uncoordinated Pb2+ ions of the perovskite material. In addition, employing the 3,4-DpACl tailors the energy levels of the perovskite layer and reduces mismatch energy between the valence band of the perovskite layer and hole transport layer (HTL). Overall, the 3,4-DpACl-contained antisolvent records a champion efficiency of 21.17% for optimized perovskite solar cells (PSCs). The optimized triple-cation PSCs show a higher stability against humidity and irradiance. They maintain 83% of their original power conversion efficiency (PCE) after 1600 h of exposure to ambient air with a humidity level of 35-40%. Furthermore, after 1056 h of irradiance with simulated sunlight in an ambient air environment, they retain 81.6% of their initial PCE.
Composition of some trace elements in wheat plant and soil
(2023) Karapınar, Hacer Sibel
Zinc, copper, nickel, and manganese are essential nutrients for plants. However, excessive accumulation in the plant can lead to significant risks and problems in terms of human health after consumption. Also, the accumulation of chromium, cadmium and lead elements in plants can have a toxic effect on human health. This study aimed to determine the concentrations of copper (Cu), chromium (Cr), cadmium (Cd), nickel (Ni), manganese (Mn), zinc (Zn), and lead (Pb) trace elements in wheat plants and soil. Mean trace element levels in soil samples taken from the city center Mn 556.9 mg kg-1, Ni 62.45 mg kg-1, Cr 24.98 mg kg-1, Zn 40.75 mg kg-1, Cu 17.25 mg kg-1, Pb 7.65 mg kg-1, Cd as 1.63 mg kg-1 and the average trace element levels in soil samples taken from villages Mn 418.7 mg kg-1, Zn 48.53 mg kg-1, Ni 32.34 mg kg-1, Cu 15.93 mg kg-1, Cr 13.7 mg kg-1, Cd 1.033 mg kg-1 was determined. Cd, Cr, and Pb concentrations were not detected in wheat samples. Average Cu (4.462 mg kg-1), Mn (30.03 mg kg-1), and Zn (20.39 mg kg-1) concentrations in wheat samples were determined at lower levels compared to soil samples. In the process of transporting trace elements from the soil to the plant, even if the plants are grown under the same conditions, the trace element levels accumulated in the plant may differ.
Design of an amorphous ZnWSe2 alloy-based counter electrode for highly efficient dye-sensitized solar cells
(The Royal Society of Chemistry, 2023) Arı, Demet Aygun; Sezgin, A.; Ünal, Muhittin; Akman, Erdi; Yavuz, I.; Liang, Fang-Cheng; Yılmaz, Mücahit; Akın, Seçkin
One of the biggest obstacles in the commercialization of dye-sensitized solar cells (DSSCs) is the use of the very expensive and rare platinum (Pt) catalytic material as a reference counter electrode (CE). Since finding new CE materials for replacing the state-of-the-art Pt is still challenging, the discovery of low-cost CE materials with superior catalytic activity is of paramount importance. Here, innovative and effective ZnWSe2 alloy CE materials in the amorphous structure are designed with different Zn ratios by the magnetron sputtering route and employed in DSSC applications to overcome the above-mentioned challenges of Pt CE. The formation of an amorphous phase with various Zn contents is further verified using theoretical calculations. Various electrochemical measurements such as cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS), and Tafel demonstrate that the optimum ZnWSe2 (denoted as ZnWSe2-3) alloy-based CE material possesses superior electrocatalytic activity, electrochemical stability, and fast reaction kinetics for an iodide/triiodide (I-/I-3(-)) redox pair. Thanks to its low charge transfer resistance, high electrical conductivity, and large surface area, the cell employing ZnWSe2-3 CE reaches a power conversion efficiency (PCE) of 8.27% with enhanced short circuit current density (J(sc)) and fill factor (FF) parameters, which are higher than those of DSSCs based on Pt (7.56%), WSe2 (6.35%), and other ZnWSe2-based CEs (6.20 to 7.41%). In addition to its improved photovoltaic (PV) performance, the cell employing ZnWSe2-3 CE exhibits prolonged photostability under operational conditions. This facile and efficient approach provides a promising direction to fabricate high-efficiency and electrochemically stable DSSCs. We thus believe that our work could provide an effective alternative for the design of high-performance and low-cost CE materials for PV applications.
An isonicotinohydrazide based fluorescence sensor for detection of Zn2+ in biological systems: Experimental and theoretical studies along with cell imagine
(Elsevier B.V., 2023) Aydın, Ziya; Keskinateş, Mukaddes; Yılmaz, Bahar; Bayrakçı, Mevlüt
Zinc ions (Zn2+) play a significant role in our daily lives and production, which is related to human health and environment protection. Therefore, it is crucial in this field to develop sensors with improved analyte selectivity and sensitivity. We prepared a fluorescent sensor, DIH, through the reaction of 5-(tert-butyl)-2-hydroxyisophthalaldehyde with isonicotinohydrazide. DIH, in free form, can undergo excited state intramolecular proton transfer (ESIPT) process upon excitation. Among a wide range of metal ions tested, only Zn2+ inhibited this ESIPT process, resulting in an increase in fluorescence intensity (13.3-fold) with chelation enhancement fluorescence process (CHEF). The complex (DIH/Zn2+) stoichiometry was determined to be 1:1 and the binding constant of the complex was estimated as 3.18 × 107 M−1. DIH could also be applied to detect zinc ions down to a low concentration level of 11.2 nanomolar with fluorescence spectroscopy. Moreover, the cytotoxicity evaluation of DIH against human colon adenocarcinoma cells lines demonstrated that the sensor was nontoxic and could be used successfully in cellular imaging
Deep learning-based classification of microalgae using light and scanning electron microscopy images
(Elsevier Ltd., 2023) Sönmez, Mesut Ersin; Altınsoy, Betül; Öztürk, Betül Yılmaz; Gümüş, Numan Emre; Eczacıoğlu, Numan
Microalgae possess diverse applications, such as food production, animal feed, cosmetics, plastics manufacturing, and renewable energy sources. However, uncontrolled proliferation, known as algal bloom, can detrimentally impact ecosystems. Therefore, the accurate detection, monitoring, identification, and tracking of algae are imperative, albeit demanding considerable time, effort, and expertise, as well as financial resources. Deep learning, employing image pattern recognition, emerges as a practical and promising approach for rapid and precise microalgae cell counting and identification. In this study, we processed light microscopy (LM) and scanning electron microscopy (SEM) images of two Cyanobacteria species and three Chlorophyta species to classify them, utilizing state-of-the-art Convolutional Neural Network (CNN) models, including VGG16, MobileNet V2, Xception, NasnetMobile, and EfficientNetV2. In contrast to prior deep learning based identification studies limited to LM images, we, for the first time, incorporated SEM images of microalgae in our analysis. Both LM and SEM microalgae images achieved an exceptional classification accuracy of 99%, representing the highest accuracy attained by the VGG16 and EfficientNetV2 models to date. While NasnetMobile exhibited the lowest accuracy of 87% with SEM images, the remaining models achieved classification accuracies surpassing 93%. Notably, the VGG16 and EfficientNetV2 models achieved the highest accuracy of 99%. Intriguingly, our findings indicate that algal identification using optical microscopes, which are more cost-effective, outperformed electron microscopy techniques.
In vitro antioxidant and cytotoxic effects of three endemic plants from Turkey based on their phenolic profile
(Taylor & Francis Ltd., 2023) Emsen, Buğrahan; Sürmen, Burak; Karapınar, Hacer Sibel
This study aimed to determine in vitro antioxidant and cytotoxic activities of acetone and water extracts obtained from Helicrysum noeanum, Onosma bozakmanii, and Sideritis amasiaca. We tested their total phenol and flavonoid content and analyzed their 14 phenolic compounds using HPLC method. Cinnamic acid, gallic acid, protocatechuic acid and quercetin were phenolics found in all extracts. Acetone extract of S. amasiaca was the experiment containing the most phenolic compounds by containing 11 of them. While the highest total phenol content belonged to water extract of S. amasiaca (189.37 mu g gallic acid equivalent/mg extract), water extract of O. bozakmanii had maximum total flavonoid rate (13.16 mu g quercetin equivalent/mg extract). Acetone and water extracts of S. amasiaca showed higher DPPH scavenging (IC50: 43.40 and 18.71 mg/L, respectively) and metal chelating (IC50: 62.26 and 61.32 mg/L, respectively) activities compared to other plants. When viability rates of human cervical cancer cells (HeLa) treated with the extracts were investigated, the experiment with the highest cytotoxic effect was acetone extract of S. amasiaca (IC50: 45.10 mg/L). Overall, our data showed that H. noeanum, O. bozakmanii and especially S. amasiaca are important natural antioxidant sources. They can be used in pharmacology thanks to their essential phytochemicals.
The effect of B-site doping in all-inorganic CsPbIxBr3−x absorbers on the performance and stability of perovskite photovoltaics
(Royal Society of Chemistry, 2023) Akman, Erdi; Öztürk, Teoman; Xiang, Wanchun; Sadegh, Faranak; Prochowicz, Daniel; Akın, Seçkin
Despite the impressive efficiency of perovskite solar cells (PSCs), their operational stability is still hindered by the thermodynamic instability of the hybrid organic-inorganic absorber layer with ABX3 structure (A: organic/inorganic cation, B: metal cation, X: halogen anion and mixtures thereof). Due to the hygroscopic and volatile nature of the organic cations, i.e., methylammonium (MA+), they show very poor stability not only against thermal stress but also moisture. Therefore, a photoactive material free from organic components could offer great opportunities to prolong the operational stability of devices. In this context, all inorganic CsPbIxBr3−x perovskites are meticulously developed in terms of their structural/thermal stability and have triggered increasing research interest due to great prospects in the commercialization of perovskite technology. However, besides relatively low performance, the poor phase stability of inorganic perovskites associated with lattice strain and vacancies still requires a thorough understanding and permanent solutions for tackling these problems. In this comprehensive review, the recently reported B-site doping strategy in inorganic CsPbIxBr3−x perovskite thin films, which has been elucidated to passivate the defects, tune the grain orientation, and enhance the lifetime of charge-carriers, is presented based on different B-site elements belonging to group IIIA, IVA and VA, alkaline-earth, transition, and lanthanide metals. Solutions for confronting these current problems are elaborated and an outlook on further strategies is given.
Trace element levels in serum and gastric mucosa in patients with Helicobacter pylori positive and negative gastritis
(Elsevier GMBH, 2022) Aslan, Ahmet; Karapınar, Hacer Sibel; Kılıçel, Fevzi; Pekin, Ceyhun; Toprak, Şükrü Salih; Boyacıoğlu, Tülin; Cihan, Mehmethan; Yılmaz Sanal, Burcu
Background: Most trace elements are inhibited by Helicobacter pylori-infection, and variations in specific element levels are linked to the development of stomach cancer. This is the first study to show the relationship between serum and tissue concentrations of twenty-five trace elements and H. pylori infection status. This study purposed to define serum and tissue trace element levels of 25 healthy individuals with Helicobacter pylori-positive gastritis and Helicobacter pylori-negative gastritis and to reveal their relationship with the disease. Methods: Study groups consisted of sixty-two patients with Helicobacter pylori-positive, thirty-seven patients with Helicobacter pylori-negative, and thirty healthy individuals. Serum and tissue concentrations of twenty-five elements (aluminum, boron, arsenic, barium, calcium, beryllium, copper, cadmium, iron, chromium, mercury, lithium, potassium, magnesium, sodium, manganese, nickel, phosphorus, lead, scandium, strontium, selenium, tellurium, titanium, zinc) were defined by inductively coupled plasma optical emission spectrometry. Results: Except for copper, lithium, and strontium elements in serum samples, other trace elements differed significantly between the groups (p < 0.05). The serum chromium (p = 0.002), mercury (p = 0.001), boron (p < 0.001), and cadmium (p < 0.001) levels of H. pylori-negative gastritis and H. pylori-positive gastritis participants were significantly different, and their serum concentrations were less than 0.5 µ/l. Boron, barium, beryllium, chromium, lithium, phosphorus and strontium elements in tissue samples did not differ significantly between the groups (p > 0.05). Manganese, nickel, tellurium and titanium elements were not detected in tissue and serum samples. The mean concentrations of calcium, beryllium, chromium, iron, potassium, lithium, magnesium, scandium, and selenium were higher in the tissues of patients with H. pylori gastritis compared to healthy control tissues. Also, cadmium could not be detected in tissue samples. There was a significant difference between H. pylori-infected tissue and serum chromium levels (p = 0.001), with lower levels detected in tissue samples. Conclusion: This is the first study that we are knowledgeable of that reports the concentrations of twenty five elements in both serum and tissue samples, as well as the relationship between trace elements and Helicobacter pylori-infection status. Dietary adjustment is indicated as an adjunct to medical therapy to stabilize trace elements because Helicobacter pylori bacteria cause inflammation and impair element absorption in gastritis patients. We also think that this study will shed light on studies on the relationship between Helicobacter pylori-trace elements and serum-tissue/healthy serum-tissue trace element levels of patients with Helicobacter pylori gastritis.

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