Mühendislik Fakültesi, Biyomühendislik Bölümü, Makale Koleksiyonu

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Highly efficient photocatalyst based on Zn2-xBaxSnO4 alloying nanoparticles with enhanced photocatalytic activity
(Elsevier, 2025) Kamo, Alaa; Sönmezoğlu, Özlem Ateş; Sönmezoğlu, Savaş
In this study, an effective Zn2-xBaxSnO4 alloying nanoparticles were hydrothermally designed with a series of barium cation as alloying dopant and utilized as a photocatalyst to decompose the rhodamine B which causes harmful effects on humans such as allergic dermatitis, skin irritation, mutation, and cancer. It is noteworthy that the Zn1.988Ba0.012SnO4 alloying-based catalyst exhibited more than 99 % degradation in only 140 min in wastewater than barium-free ternary oxide. Moreover, the reaction rate of Zn1.988Ba0.012SnO4 alloying-based catalyst was enhanced to 0.032 min-1 compared with barium-free ternary oxide (0.0179 min-1). Based on scavenger trapping experiments, hydroxyl radicals are the main reactive oxygen species responsible for photocatalytic activity of Zn1.988Ba0.012SnO4 alloying-based catalyst. Besides, the photocatalytic rate was maintained 94.89 % after 5th cycle. This research not only provides a novel strategy for developing alloying-based catalysts but also unveils their potential in photoelectrochemistry and photocatalysis.
Functional properties of betalains: binding of hg2+ and cu2+ ions, sensor capabilities, and antimicrobial activity
(Wiley, 2025) Şen Arslan, Hülya; Yılmaz Altınok, Bahar
In this study, betalain extracts were obtained from prickly pear (PPE), dragon fruit (DFE), and red beet (RBE). The total betalain content of the extracts was determined to be 335.5 mg/L for PPE, 372.38 mg/L for DFE, and 466.21 mg/L for RBE, respectively. Fluorescence titrations with metal cations revealed PPE's highest intensity at 280 nm excitation, with DFE and RBE also responding, though less so. The fluorescence intensity for all extracts decreased significantly upon adding Hg2+ and Cu2+, indicating strong binding. PPE and DFE showed higher sensitivity and affinity for these ions than RBE. Absorption at 350 nm increased notably, along with visible color changes enabling potential 'naked-eye' detection. These extracts demonstrated high selectivity for Hg2+ and Cu2+, even with competing cations. Antibacterial tests showed significant inhibition against gram-positive and gram-negative bacteria. These findings, the extracts' strong spectral responses and anti-interference properties support their use as selective, sensitive sensors for environmental monitoring and analytical applications. Due to their inherent fluorescence properties, betalains have significant potential as biosensors.
High-throughput phenotyping of wheat root angle and coleoptile length at different temperatures using 3D-printed equipment
(2025) Aydın, Nevzat; Sönmez, Mesut Ersin; Güleç, Tuğba; Demir, Bedrettin; Alipour, Hadi; Türkoğlu, Aras
BackgroundInnovation in crop establishment is crucial for wheat productivity in drought-prone climates. Seedling establishment, the first stage of crop productivity, relies heavily on root and coleoptile system architecture for effective soil water and nutrient acquisition, particularly in regions practicing deep planting. Root phenotyping methods that quickly determine coleoptile lengths are vital for breeding studies. Traditionally, direct selection for root and coleoptile traits has been limited by the lack of suitable phenotyping methods, genetic and phenotypic complexity, and poor repeatability in sampling. In this study, we innovated a method utilizing 3D printing technology to measure root angle and coleoptile length in wheat seedlings. We evaluated seedlings from eight different wheat genotypes across varying temperatures and validated our findings through image processing techniques.ResultsThe analysis of variance in root architecture revealed significant differences among genotypes for root angle. Temperature treatments also significantly influenced shoot length, number of roots and total root length. The Tosunbey genotypes exhibited the highest root angle and the lowest root angle was observed in Altindane genotypes. Additionally, we observed that increasing the temperature led to an increase in seedling root length. Similarly, the coleoptile architecture analysis showed significant differences among genotypes in coleoptile length, leaf length, number of roots, and total root length. Temperature treatments and deep sowing applications significantly affected these traits as well. The Tosunbey and M & uuml;fitbey genotypes exhibited the longest coleoptile length, whereas the Nevzatbey genotype showed the shortest.ConclusionSelecting for a narrow root angle and a high number of seminal roots can result in deeper, more branched root systems. Furthermore, developing wheat genotypes with longer coleoptiles can enhance plant production and early vigor, particularly with deep sowing. Our method, using the eqiupments producing by 3D printing technology enables high-throughput phenotyping of wheat roots and coleoptiles, offering new insights into root and coleoptile system regulation at different temperature conditions. This method can be seamlessly integrated into breeding programs to enhance drought tolerance, rapidly phenotyping populations for root and coleoptile characteristics.
Green synthesis of iron oxide nanoparticles from extracts of Daucus carota subsp. sativus whole vegetable, peel, pomace, and juice and their application as antibacterial agents and Fenton-like catalysts
(Wiley, 2025) Kirtiş, Evrim Burcu Uncu; Koçak, Deniz Yiğit; Eldervis, Ukba; Tuna, Süheyla; Bayraç, Ceren
The green synthesis of iron oxide nanoparticles (Fe-NPs) with catalytic and antimicrobial activities from the extracts of different parts of Daucus carota subsp. sativus var. atrorubens Alef. was demonstrated in this study. The extracts of whole vegetable, peel, pomace, and juice acted as a reducing agent for the bio-reduction of Fe3+ into Fe-NPs. The synthesis of Fe-NPs was indicated by surface plasmon peaks within the range of 200-300 nm, as well as characteristic iron oxide bond formation in the region of 400-850 cm-1 using an ultraviolet-visible spectrophotometer and FT-IR spectrophotometer, respectively. The green synthesised Fe-NPs from the whole vegetable and its byproduct extracts had uniform quasi-spherical structures, with average particle sizes of 87.13, 80.95, 103.14, and 86.26 nm from whole vegetable extract, peel extract, pomace extract, and juice, respectively. All synthesised particles exhibited excellent Fenton-like catalytic activities on the discoloration of methylene blue best fitting the pseudo-first order kinetic model for Fe-NPs from whole vegetable extract, pomace extract, and juice and the pseudo-second order kinetic model for Fe-NPs from peel extract. In addition to catalytic activity, Fe-NPs showed antibacterial activity against Escherichia coli, Staphylococcus aureus, and Bacillus subtilis. The antibacterial effects of Fe-NPs alone and their synergistic effects with antibiotics have been observed in both Gram-positive and Gram-negative bacteria.
Biosynthesis and characterization of silver nanoparticles mediated by cistus salviifolius L. and Ferula communis L. extracts and evaluation of their antioxidant, antibacterial, and cytotoxic potentials
(Pleiades Publishing Inc, 2024) Ulusu, Funda; Ulusu, Yakup
In this research, we employed a microwave-assisted green synthesis method utilizing extracts from Cistus salviifolius L. and Ferula communis L. to synthesize silver nanoparticles (AgNPs). Subsequently, we characterized the biosynthesized AgNPs, both Cs-AgNPs (derived from C. salviifolius) and Fc-AgNPs (derived from F. communis), through UV-Vis, FT-IR, XRD, SEM, and TEM analyses. The AgNPs exhibited a spherical shape with sizes averaging below 11 nm. To assess their antioxidant activity, we employed the DPPH method. Furthermore, we examined the antimicrobial potential of Cs-AgNPs and Fc-AgNPs against pathogenic bacterial strains, including Bacillus subtilis, Staphylococcus aureus, Enterococcus faecalis, and Escherichia coli, using the disc diffusion assay and minimum inhibitory concentration. Additionally, we evaluated the cytotoxic effects of Cs-AgNPs and Fc-AgNPs on various cell lines, namely breast adenocarcinoma (MCF-7), colon carcinoma (HT-29), human keratinocytes (HaCaT), and embryonic kidney (HEK-293), employing the Alamar Blue assay. Our findings indicate that the biosynthesized Cs-AgNPs and Fc-AgNPs possess antioxidant, antibacterial, and anticancer activities. Therefore, the current study suggests that Cs-AgNPs and Fc-AgNPs exhibit potential for treating cancer and diseases caused by pathogenic microorganisms.
Long-duration type 1 diabetes is associated with deficient cortical bone mechanical behavior and altered matrix composition in human femoral bone
(Oxford Univ Press, 2024) Emerzian, Shannon R.; Unal, Mustafa; Brooks, Daniel J.; Wu, I-Hsien; Gauthier, John
Type 1 diabetes (T1D) is associated with an increased risk of hip fracture beyond what can be explained by reduced bone mineral density, possibly due to changes in bone material from accumulation of advanced glycation end-products (AGEs) and altered matrix composition, though data from human cortical bone in T1D are limited. The objective of this study was to evaluate cortical bone material behavior in T1D by examining specimens from cadaveric femora from older adults with long-duration T1D (>= 50 yr; n = 20) and age- and sex-matched nondiabetic controls (n = 14). Cortical bone was assessed by mechanical testing (4-point bending, cyclic reference point indentation, impact microindentation), AGE quantification [total fluorescent AGEs, pentosidine, carboxymethyl lysine (CML)], and matrix composition via Raman spectroscopy. Cortical bone from older adults with T1D had diminished postyield toughness to fracture (-30%, p = .036), elevated levels of AGEs (pentosidine, +17%, p = .039), lower mineral crystallinity (-1.4%, p = .010), greater proline hydroxylation (+1.9%, p = .009), and reduced glycosaminoglycan (GAG) content (-1.3%, p < .03) compared to nondiabetics. In multiple regression models to predict cortical bone toughness, cortical tissue mineral density, CML, and Raman spectroscopic measures of enzymatic collagen crosslinks and GAG content remained highly significant predictors of toughness, while diabetic status was no longer significant (adjusted R-2 > 0.60, p < .001). Thus, the impairment of cortical bone to absorb energy following long-duration T1D is well explained by AGE accumulation and modifications to the bone matrix. These results provide novel insight into the pathogenesis of skeletal fragility in individuals with T1D.
An Application of a Schiff-Base Type Reaction in the Synthesis of a New Rhodamine-Based Hg(II)-Sensing Agent (vol 29, pg 1349, 2019)
(Springer/Plenum Publishers, 2020) Çiçekbilek, Fulya; Altınok, Bahar Yılmaz; Bayrakcı, Mevlüt; Gezici, Orhan
[Abstract Not Available]
Streptococcus pneumoniae için DNA Aptamerlerinin Geliştirilmesi ve Karakterizasyonu
(2016) Bayraç, Abdullah Tahir; Dönmez, Sultan İlayda
Pnömokoklar çocuklarda, yaşlılarda ve immün yetmezliği olanlarda sebep olduğu enfeksiyonlarla dünyada başta gelen enfeksiyon nedenleri arasında bulunmaktadır. Son yıllarda antibiyotiklere dirençli Streptococcus pneumoniae suşları giderek yaygınlaşmaktadır. Aptamerlerin yüksek afinite ve seçicilikleri onları terapötik, biyoanalitik ve moleküler tanı alanında kolaylıkla kullanılabilen ajanlar haline getirmektedir. Bakteriyel-SELEX aptamer üretim yöntemi ile bakterilerdeki bilinmeyen biyomarkörlerin tespit edilmeleri sağlanabilmekte ve geliştirilen bu aptamerler tanı amaçlı kullanılabilmektedir. Bu çalışmada S. pneumoniae’ya karşı bakteriyel SELEX yöntemi kullanılarak aptamerler geliştirilmiştir. SELEX esnasında S. pneumoniae (ATCC® 49619™) hedef hücre olarak kullanılırken, Streptecoccus mutans (ATCC® 25175™), Streptococcus pyogenes (ATCC® 19615™) ve Enterococcus faecalis (ATCC® 19433™) negatif seçilimde kullanılarak aptamerlerin özgünlüğü arttırılmıştır. Yapılan 20 turluk SELEX sonrasında zenginleşen diziler yeni nesil dizileme ile belirlenmiş ve sentezlenmiştir. Test edilen aptamerler arasında 3 aday nanomolar seviyede (844,7±163,6 nM, 1984,8±347,5 nM, 661,8±111,3 nM) Kd değerlerine sahip olup seçilimde kullanılan diğer bakterilere etkin bağlanma göstermemiştir. Aptamerlerin bağlanma etkinlikleri floresans spektroskopi, floresans mikroskopi ve akım sitometrisi kullanılarak gösterilmiştir. Bununla birlikte geliştirilen aptamerlerin biyofilm oluşumunu seçici olarak inhibe ettiği gösterilmiştir. Geliştirilen bu aptamerler literatürde bulunan ilk S. pneumoniae aptamerleridir, fonksiyonel olarak S. pneumoniae’e bağlanmakta ve anti pneomococcal potansiyeli bulunmaktadır.
Herpetik Keratitis Tanısında Kullanılmak Üzere Tip1 Herpes Simpleks Virüsünü Hedefleyen DNA Aptamerlerinin Geliştirilmesi
(2018) Çağıl, Nurullah; Özkul, Aykut; Bayraç, Abdullah Tahir
Herples simplex virüs tip1 (HSV1) keratitis hastalığı, kornea körlüğünün ve mikrobik körlüğün en önemli sebebidir. Herpetik keratitis hastaları ağrı, ışık duyarlılığı, bulanık görüş, göz yaşarması ve kızarıklık yaşarlar. Kornea körlüğü, hastalığın geç tanısı sebebiyle tedavide geç kalınması sonucu oluşur. Tedavide geç kalınmaması için HSV1 virüsünün hızlı ve düşük maliyetle tespit edilmesini sağlayacak bir yöntem veya kit gereklidir. Bu eksikliğin kapatılması için geliştirilecek bir biyosensörde temel ihtiyaç HSV1 ile diğer virüslerin ve özellikle HSV2?nin ayırt edilebilmesini sağlayacak bir işaretçi moleküldür. Antikorlar, hedef moleküllerin seçilmesini sağlayan ve halen yaygın olarak kullanılan peptid temelli biyosensör elemanlarıdır fakat antikorların da kendilerine özgü eksiklikleri vardır. Aptamerler ise, antikorlar kadar yüksek bağlanma özgünlüğüne sahip nükleik asit temelli moleküllerdir. Teorik olarak herhangi bir moleküle özgün olarak bağlanabilen bir DNA veya RNA aptamer molekülü bulunabilir. Aptamerler ile seçilebilecek hedef moleküller ATP kadar ufak olabilmektedir ve DNA aptamerleri biyosensörlerde kullanılmak için gerekli stabiliteye sahiptir. HSV1 virüsünün teşhisi, eğer doktor tarafından klinik muayenede konulamamış ise, halen kültür ve bazı durumlarda PCR ile yapılmaktadır fakat bu süreç birkaç haftayı bulabilmektedir. Hızlı ve düşük maliyetli virüs tespiti biyosensörleri henüz ticari olarak bulunmasa da bir biyosensörde kullanılması gereken hedefleyici molekül ihtiyacı aptamer ile sağlanabilecektir. Bu projemizde biyosensörlerde kullanılacak HSV1?e özgü aptamer geliştirilmeye çalışılmıştır. Bunun için SELEX yapılarak zenginleştirilmiş DNA havuzları elde edilmiştir.
Production of plant-based ZnO NPs by green synthesis; anticancer activities and photodegradation of methylene red dye under sunlight
(Springer Science and Business Media Deutschland GmbH, 2024) Demir, Canan; Aygün, Ayşenur; Gündüz, Meliha Koldemir; Altınok, Bahar Yılmaz; Karahan, Tuğba; Meydan, İsmet; Halvacı, Ebru
Discharging wastewater from factories into streams without cleaning them causes environmental pollution and threatens the health of living beings. The photocatalysis method developed for easy, fast, and low-cost wastewater cleaning attracts considerable attention and therefore needs to synthesize efficient photocatalysts. In addition, the synthesized non-toxic catalysts can be tested as anticancer agents and may be suitable candidates to solve the issues facing cancer therapy today. Therefore, the synthesis of biogenic nanomaterials has gained importance. Plant-mediated green synthesis stands out in the simple, fast, cheap, and non-toxic production of nanoparticles (NPs). NPs produced by green synthesis are frequently used in biological applications such as anticancer and photocatalyst applications for cleaning wastewater. In this article, zinc oxide nanoparticles (ZnO NPs) were obtained using Zingiber officinale extract. The plant extract functions as a reducing, capping, and stabilizing agent in the green production of ZnO NPs. The synthesis of ZnO NPs was characterized using UV–Vis spectroscopy, FTIR, XRD, and TEM. TEM results show that ZnO NPs have sizes in the range of 10–45 nm. The anticancer activity of ZnO NPs was examined against HT29 (ATCC® HTB-38™) colorectal cancer cell line and HepG2 (ATCC® HB-8065™) hepatocellular cancer cell line by MTT assay. The IC50 values of ZnO NPs against HT29 and HepG2 cancer cell lines after 48 h were calculated as 20 µg/mL and 45 µg/mL, respectively. Additionally, the photocatalytic activity of ZnO NPs was tested against methylene red azo dye under sunlight and 87.96% (pH 7) photodegradation was obtained at the end of the 120th minute. It is predicted that ZnO NPs can be used effectively in both anticancer studies and environmental improvement. © The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature 2024.
Convolutional neural network-support vector machine-based approach for identification of wheat hybrids
(Springer Science and Business Media Deutschland GmbH, 2024) Sönmez, Mesut Ersin; Sabancı, Kadir; Aydın, Nevzat
Selecting wheat hybrids is vital for enhancing crop yield, adapting to changing climates, and ensuring food security. These hybrids align with market demands and sustainable farming practices, contributing to efficient crop management. Traditional methods for wheat hybrid selection, such as molecular techniques, are costly and time-consuming, and are prone to human error. However, advancements in artificial intelligence and machine learning offer non-destructive, objective, and more efficient solutions. This study is explored the classification of wheat varieties and hybrids using two deep learning models, MobileNetv2 and GoogleNet. These models are achieved impressive classification accuracy, with MobileNetv2 reaching 99.26% and GoogleNet achieving 97.41%. In the second scenario, the deep features obtained from these models are classified with Support Vector Machine (SVM). In the classification made with the MobileNetv2-SVM hybrid model, an accuracy of 99.91% is achieved. This study is provided rapid and accurate wheat variety and hybrid identification method, as well as contributing to breeding programs and crop management.
Kloramfenikol aptameri fonksiyonlandırılmış DNA hidrojellerinin sentez koşullarının optimizasyonu
(2023) Bayraç, Ceren; Aran, Gülnur Camızcı
Aptamer fonksiyonlandırılmış DNA hidrojelleri yüksek özgünlük, stabilite ve esneklik gibi özellikleri nedeniyle birçok alanda kullanılmaktadır. Bu çalışma kapsamında kloramfenikole özgü aptamer dizisi fonksiyonlandırılmış DNA hidrojeli sentezi gerçekleştirilmiş ve hidrojel stabilitesi için önemli parametreler optimize edilmiştir. Sentez için 5’ uçları akridit modifiyeli kloramfenikole özgü aptamer ile ona kısmen eşlenik DNA ipliği polimer yapıya yan dal olarak katılmış ve eşlenik bölgelerin hibridizasyonu ile bir arada tutularak hidrojel sentezi gerçekleştirilmiştir. Optimize edilmiş parametreler akridit modifiyeli DNA dizilerinin konsantrasyonları, akrilamid yüzdesi, kloramfenikol aptameri ve DNA iplik 1 içeren lineer polimer çözeltilerin molar oranlarıdır. Ayrıca, reaksiyon sıcaklığı ve eşlenik bölgenin uzunluğunun jel stabilitesine etkisi değerlendirilmiştir. Sonuç olarak, DNA hidrojel stabilitesi için %60’lık lineer poliakrilamid-DNA konjugasyonundan, %40 akrilamid stok çözeltisi kullanılarak 1:1 molar oranda karıştırılan aptamer ve DNA iplik çözeltileri ile 25°C’de aptamer fonksiyonlandırılmış DNA hidrojeli sentezi tamamlanmıştır. Bunlara ek olarak, aptamer dizisi ile DNA iplik arasındaki eşlenik bölgenin uzunluğunun stabiliteyi artırdığı sonucuna varılmıştır.
A Study on phytochemical composition, antioxidant, and anti-cancer activities of Gingko biloba L.
(ABADER (Adıyaman Bilimsel Arastırmalar Dernegi), 2023) Deveci, Ebru; Altınok, Bahar Yılmaz; Çayan, Gülşen Tel
The study aims to investigate the phytochemical composition, antioxidant potential, and anti-cancer activities of Ginkgo biloba L. leaf methanol extract. In this study, the phytochemical compounds, total phenolic and flavonoid contents of G. biloba leaf methanol extract were investigated. Additionally, antioxidant and anti-cancer activities [against HT-29 (human colon cancer line), HeLa (human cervical cancer line), and HEK-293 (human embryonic kidney cell line)] were assayed. The main phytochemical compounds were identified as gallic (0.94±0.01 mg/g), p-hydroxy benzoic (0.71±0.01 mg/g), and protocatechuic (0.60±0.02 mg/g) acids in G. biloba leaf methanol extract by HPLC. The total phenolic and total flavonoid contents were measured as 71.20±0.42 µg GAE/mg extract and 13.24±0.35 µg QE/mg extract, respectively. The high antioxidant activity was found in ABTS•+ assay (89.04±0.71%) while moderate antioxidant activity was observed in DPPH• (43.31±0.75%), metal chelating (49.04±0.49%), CUPRAC (absorbance: 0.85±0.01), and phosphomolybdenum (absorbance: 1.16±0.02) assays at 400 µg/mL. The IC50 values of G. biloba leaf methanol extract on HT-29, HeLa, and HEK-293 cell lines were recorded as 406.70±1.55, 84.86±0.98, and >800 µg/mL, respectively. The present study features a new addition to the antioxidant and anti-cancer properties of the therapeutically valuable G. biloba with its phytochemical content. © 2023, ABADER (Adıyaman Bilimsel Arastırmalar Dernegi). All rights reserved.
Chemical characterization, in vitro antioxidant, anti-cancer and enzyme inhibition activities of three edible mushroom species
(Springer, 2023) Deveci, Ebru; Tel-Çayan, Gülsen; Çayan, Fatih; Yılmaz Altınok, Bahar; Aktaş, Sinan
This study aimed to investigate HPLC-DAD based chemical compositions, total phenolic compounds, antioxidant, enzyme inhibition and anti-cancer activities of three edible mushrooms: Clavariadelphus truncatus Donk, Craterellus tubaeformis (Fr.) Quél. and Hygrophorus pudorinus (Fr.) Fr. p-Hydroxy benzoic acid was specified as the main compound in C. truncatus methanol extract (67.40 ± 0.18 µg/g), trans-aconitic acid in C. tubaeformis water extract (129.50 ± 0.11 µg/g), fumaric acid in other mushroom extracts (138.80 ± 0.25–203.40 ± 0.36 µg/g). C. truncatus methanol extract (DPPH•: IC50: 133.99 ± 0.30 µg/mL; ABTS•+: IC50: 120.95 ± 0.93 µg/mL; CUPRAC: A0.50: 108.10 ± 0.42 µg/mL; PRAP: A0.50: 116.81 ± 1.18 µg/mL; metal chelating: IC50: 143.18 ± 0.22 µg/mL) was the most active in antioxidant activity with the highest level of total phenolic compounds (29.18 ± 0.70 µg GAEs/mg extract). When C. tubaeformis water extract (42.13 ± 0.51%) was the highest active in AChE inhibition activity, C. tubaeformis hexane extract (29.14 ± 0.04%) was the highest active in BChE inhibition activity at 200 µg/mL. All hexane extracts displayed the high inhibition on α-amylase (47.82 ± 1.16–81.06 ± 0.54% inhibition at 0.50 mg/mL) and α-glucosidase (IC50: 0.11 ± 0.01–0.13 ± 0.02 mg/mL). C. truncatus water (IC50: 36.19 ± 0.95 µg/mL) and C. tubaeformis methanol (IC50: 48.26 ± 0.51 µg/mL) extracts indicated the highest anti-cancer activity on HT-29. Also, C. tubaeformis methanol extract (IC50: 68.93 ± 0.87 µg/mL) was also found to be best anti-cancer active in HeLa. Also, the significant correlation was observed between the chemical compounds and bioactivities. This research affords a scientific basis for the exploration of novel and natural antioxidant, enzyme inhibition and anti-cancer sources with the chemical contents. All studied mushrooms could be used in food, pharmaceutical, and cosmetic 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
Antioxidant responses to drought stress in pennyroyal (Mentha pulegium L.)
(Kütahya Dumlupınar Üniversitesi Lisansüstü Eğitim Enstitüsü, 2022) Ulusu, Funda; Tümer, Kader; Ulusu, Yakup
Mentha pulegium L. (Lamiacea) is a valuable medicinal and aromatic plant found in humid and arid bioclimatic regions of Turkey. Drought stress is a growing concern for the future of agriculture, as well as the most common abiotic stress factor affecting the biochemical processes of plants and seriously damaging crop productivity. The aim of the study was to evaluate the effects of drought stress on the activity of enzymatic antioxidants (polyphenol oxidase - PPO, peroxidase - POD, ascorbate peroxidase - ASPX, catalase - CAT) and some ecophysiological (total chlorophyll content, chlorophyll a and b, carotenoid) responses in M. pulegium grown in pots under greenhouse conditions. In addition, oxidative stress markers were analysed to determine whether drought stress causes oxidative damage in pennyroyal. The plants were exposed to water stress during the 3rd, 6th and 10th days. All enzymatic antioxidant activities of plants under stress were increased compared to control plants. While there was a significant increase in PPO and POD activities in the first days of drought treatment, the prolongation of the treatment period resulted in a significant decrease in these activities. In addition, drought significantly increased lipid peroxidation (294%), hydrogen peroxide (158%) and proline (3172%) content compared to controls. These results show that drought treatment and duration significantly affect antioxidant enzyme activities, lipid peroxidation, hydrogen peroxide and proline content. DPPH (2-diphenyl-1-picrylhydrazyl), ABTS (2,20’-azino-bis (3-ethylbenzothiazoline-6-sulphonic acid)) radical scavenging activity, Fe+2 (FRAP) reducing activity and total phenolic content analysis were performed to analyse the effects of drought stress on antioxidant properties of pennyroyal plant. In addition, the decrease in photosynthetic pigment content in parallel with the prolongation of the drought period due to oxidative damage shows that this valuable medicinal and aromatic plant has low tolerance to drought.
Aktif tabakaya Ag nanopartikül katkısının organik güneş hücrelerinin fotovoltaik verimine etkisi
(Bilecik Şeyh Edebali Üniversitesi, 2022) Yurtdaş, Semih; Ünal, Muhittin; Tozlu, Cem
Organik güneş hücreleri alternatif enerji kaynaklarından bir tanesidir. Bu teknolojinin ticarileşebilmesinin önündeki tek engel düşük verimlilik değerleridir. Bu çalışmada evrik yapıdaki organik güneş hücrelerinin verimi Ag nanopartiküllerin (np) plazmonik etkilerinden yararlanarak arttırılmıştır. Aygıt konfigürasyonu ITO/ZnO/poli(3-hekziltiofen-2,5-diil) (P3HT): (6,6)-fenil C61 bütirik asit metil ester (PCBM)/MoO3/Ag şeklindedir. Ag np’ler poliol yöntemi ile sentezlenmiş ve X-Işını difraktometresi (XRD) UV-Vis spektrofotometre ve alan emisyonlu taramalı elektron mikroskopu (FESEM) ile karakterize edilmiştir. Daha sonrasında Ag, kütlece %0,125-0,25-0,5 oranlarında P3HT:PCBM’e katkılanmıştır. Referans hücrede verim değeri %3,21 iken %0,25 Ag katkılı aygıtta yaklaşık %7’lik bir verim artışı ile %3,43 değerine ulaşılmıştır.
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.
Assessment of some bread wheat (Triticum aestivum L.) genotypes for drought tolerance using SSR and ISSR markers
(TAGEM Journals, 2022) Sönmezoğlu, Özlem Ateş; Çevik, Elçin; Aksoy Terzi, Begüm
As a result of the rapid increase in the world population, the need for wheat, which is one of the main nutrition in the human diet, is also rapidly increases. However, due to yield losses caused by abiotic stress factors such as drought, wheat production is not sufficient. Therefore, genetic characterization studies performed on wheat genotypes in terms of drought tolerance are important. In this study, genetic characterization of wheat genotypes regardingdrought tolerance was carried out by using molecular markers associated with drought-tolerance genes. For this purpose, 14 polymorphic markers were used to be able to distinguish between the control groups. Genetic characterization of 27 bread wheat genotypes by using eight ISSR markers revealed a polymorphism rate of 75.8%, and the mean PIC was calculated as 0.55. Based on the results of the genetic characterization performed with six SSR markers, the mean PIC value was 0.77, the mean He was 0.79, and the mean allele number was 6.7. In this study, the characterization of drought-tolerant and sensitive genotypes was carried out, and the potentials of genotypes for breeding studies were revealed. This study also indicates that used SSRs and ISSRs markers are useful in marker-assisted breeding about drought tolerance.
Magnetic solid-phase extraction of fipronil from aqueous solution and eggshells using amine coated iron oxide nanoparticles
(Wiley, 2023) Aran, Gülnur Camızcı; Bayraç, Ceren
Fipronil, as a broad use insecticide, is regulated under directives and standards in many countries since it is classed as Class II moderately hazardous pesticide and Group C possible human carcinogen. In this study, amine coated iron oxide (NH2-Fe3O4) is used as a new adsorbent with high adsorption capacity in the removal of fipronil from aqueous solution and eggshells. The adsorption performance was studied through batch adsorption under different concentrations of fipronil (10-200 µg/mL), different nanoparticles amount (0.1-1 mg) at different pH (4.5-6.0) and temperature (25-75°C). Results showed that NH2-Fe3O4 nanoparticles (0.1 mg) have excellent adsorption efficiency (97.06%) at 25°C, and pH 5.5. It also showed higher adsorption capacity towards fipronil sulfide, fipronil sulfone and fipronil desulfinyl with removal efficiencies of 92.82%, 86.35% and 76.24% from aqueous solution and 97.62%, 76.97% and 62.65% from eggshells, respectively. Fipronil adsorption process on NH2-Fe3O4 nanoparticles showed best fitting to Langmuir adsorption isotherm indicating monolayer chemical adsorption by physicochemical interactions spontaneously on homogenous surfaces. Having higher adsorption capacity and reusability NH2-Fe3O4 nanoparticles were shown to be effective adsorbents for removal of fipronil from aqueous solution and eggshells.

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