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Investigation and Quantification of Phthalate Esters in Packaged Milk: A Study in Türkiye النص الكامل
2024
Gürsel İşçi
The aim of this study was to explore the concentrations of PAEs (Phthalate esters) in milk in Türkiye. For this purpose, a methodology was developed to quantify eight different PAEs in milk samples using a combination of dispersive solid-phase extraction (dSPE) and Liquid Chromatography coupled with Tandem Mass Spectrometry (LC-MS/MS). Employing this methodology, the concentrations of PAEs were evaluated in 34 milk samples. Results indicated the presence of PAEs in the milk samples; however, all tested compounds remained within the specific migration limits established by the EU. Among the analyzed PAEs, BBP (Benzyl butyl phthalate) was not detected in any samples, while DMP (di-methyl phthalate) (ND-5.51 µg/L) and DBP (di-butyl phthalate) (ND-7.91 µg/L) exhibited the lowest concentrations. DEHP (bis(2-ethylhexyl)) was identified as the most prevalent plasticizer with a maximum concentration of 41.31 µg/L. In conclusion, this study successfully investigated PAE concentrations in Turkish milk samples using a developed methodology. The results indicated the presence of PAEs within EU-established limits, with DEHP being the predominant plasticizer. Further research and monitoring efforts are crucial to ensure ongoing safety in packaged milk products.
اظهر المزيد [+] اقل [-]Comparison of Extraction Techniques for Determining Bioactive Compounds and Antioxidant Activity of Spirulina platensis النص الكامل
2024
Türkan Uzlaşır | Hatice Kübra Şaşmaz | Haşim Kelebek
Spirulina platensis (S. platensis) is a high-nutrient blue-green algae that has been used as a food supplement for a long time. It contains carbohydrates, lipids, proteins, vitamins, minerals, and bioactive compounds essential for basic human nutrition. It is known to have anti-cancer, antioxidant, anti-inflammatory, neuroprotective, hepatoprotective, and hypocholesterolemic properties due to the bioactive compounds it contains. In this study, the effects of freeze-thawing, a rapid freezing (-20°C) and thawing (4°C) process, and ultrasonically assisted extraction techniques on the color, antioxidant capacity, total phenolic content, and phenolic composition of Spirulina platensis extracts were investigated. The antioxidant capacity of the extracts obtained was determined by two different methods, DPPH (2,2-diphenyl-1-picryl hydrazyl) and ABTS (2,2-azinobis (3-ethylbenzothiazollin-6-sulfonic acid)). The sugar profile was determined by HPLC-RID and phenolic composition was determined by HPLC-ESI-DAD-MS/MS. The antioxidant activity and total phenolic content of samples prepared by the freeze-thawing were higher than those prepared by ultrasonic-assisted conventional extraction technique. In addition to ferulic acid 4-O-glucuronide and brevifolin carboxylate, an isocoumarin derivative, as the dominant phenolic compound in S. platensis extracts, a total of 10 phenolic compounds including catechin isomer, resveratrol C-hexoside, myricetin, ferulic acid, gallic acid, phloroglucinol, and lutein were detected. Glucose was the predominant sugar in both samples. The total sugar content was higher in the freeze-thawed samples (217.92 mg/100 g DW) than in the ultrasonic-assisted conventional extraction technique (182.91 mg/100 g DW). S. platensis has a significant amount of antioxidants, valuable secondary metabolites, and potential commercial applications and medicinal properties, but releasing these compounds is difficult due to the cell wall. This study was carried out to determine how different extraction techniques alter the release of bioactive compounds.
اظهر المزيد [+] اقل [-]Morphological and Physiological Responses of Different Cotton Genotypes Primed with Salicylic Acid Under Salinity Conditions النص الكامل
2024
Nimet Ozege | İlkay Yavaş | Emre İlker
This study was conducted as both petri dishes and pot experiments on four different salt-sensitive cotton genotypes (Laser, May 505, May 455 and Selin) in order to investigate the role of exogenous salicylic acid applications in reducing the effects of salt stress. Six saline treatments; 0, 30, 60, 90, 120 mM NaCl were used. Each group divided into three sub-groups (hydo-primed control, 0.5 mM and 1.0 mM SA) on the basis of seed priming treatments. They were applied in three replications according to the randomized block design. In all genotypes, 90 mM and 120 mM salt stress negatively affected germination and seedling development. In salt stress up to 60 mM, it was recommended to May 505 and Selin genotypes with 0.5 mM salicylic acid pre-application to the seeds.
اظهر المزيد [+] اقل [-]Silicon Improves Cold and Freezing Tolerance in Pea النص الكامل
2024
Ufuk Akçay | Hande Nur Kumbul | İbrahim Ertan Erkan
The most significant crop losses worldwide occur due to unfavorable temperatures such as heat, drought, cold, and freezing. Minerals like silicon can play important roles in the growth, development, and stress responses of plants. In this study, changes in stem/root length, dry weight, relative water content and silicon content, of peas under cold and freezing stress, as well as antioxidant system indicators such as proline, malondialdehyde, hydrogen peroxide, and chlorophyll levels, ion leakage, and the expressions of genes coding for the topoisomerase TOP2 and DNA helicase PDH47 enzymes, which play important roles in the replication, transcription, and repair of DNA molecules, were examined in root and stem tissues in the presence of two different concentrations of silicon. The results of the study showed that silicon application under cold and freezing stresses has induced various changes in pea metabolism, including increases in cell membrane integrity parameters and superoxide dismutase enzyme activity, as well as increase in the expressions of TOP2 and PDH47 genes. These changes have been found to have positive effects on the pea cold and freezing tolerance.
اظهر المزيد [+] اقل [-]Response of spring rice (Oryza sativa L.) varieties to different nitrogen application methods at Nawalparasi West, Nepal النص الكامل
2024
Himsweta Bhatt | Sudip Ghimire | Sushma Paudel | Manju Bashyal
Rice (Oryza sativa L.) cultivation necessitates an adequate supply of nitrogen to achieve optimal growth and yield. This study, conducted in Nawalparasi West from February to June 2023, aimed to assess the effects of nitrogen management through a foliar spray of nano urea, compared to need-based nitrogen management using the Leaf Color Chart (LCC) and the Recommended Dose of urea Fertilizer (RDF) application. The experiment followed a Randomized Complete Block Design (RCBD) with three replications, incorporating four nitrogen management levels (Control, RDF through urea fertilizer (120 kg/ha), 25% of RDF through basal urea (30 kg/ha) + nano urea, and 25% of RDF through basal urea (30 kg/ha) + (LCC) and two rice varieties (Chaite-5 and Hardinath-1). The results indicated that the LCC-based treatment produced the highest grain yield at 5.18 mt/ha, statistically similar to the yield of the nano urea-based treatment (5.04 mt/ha). The enhanced yields were attributed to more effective tillers per m² (260.17 tillers/m² and 253.17 tillers/m², respectively), longer panicle length (28.12 cm and 25.99 cm), more filled grains per panicle (210.03 and 215.73), and lower sterility percentage (24.93% and 26.95%). Despite comparable yields, nano urea application proved to be more cost-effective [97,926.10 Nepalese Rupees (NRs)] with a higher benefit-cost ratio (1.78) and greater ease of application for farmers compared to the LCC. Varietal responses varied, with Hardinath-1 exhibiting the highest yield with LCC-based nitrogen application (5.37 mt/ha), and Chaite-5 demonstrating the highest yield (4.778 mt/ha); with nano urea-based nitrogen application (5.31 mt/ha). Chaite-5 displayed a greater effective number of tillers per m² (241.42 tillers/m²) and filled grains per panicle (224.56). Consequently, it is suggested that nano urea-based nitrogen application, particularly in conjunction with a variety of Chaite-5, holds the potential for improved productivity.
اظهر المزيد [+] اقل [-]An Assessment of Forestry Policy in The European Union, Turkey and Various Countries النص الكامل
2024
Dilek Güleç Uğur | Tayyibe Altunel
In many parts of the world, forests have been seen only as an economic value and forestry policies have been in this direction. Later, when forests started to disappear, the protectionist period started and forest policies were shaped in this direction. In this study, the reflections of sustainable foresty policy and environmental and forest protection in the Eurpoion Union (EU), Turkey and a few other countries are examined and the protection measures and recommendations of the countries are analyzed. The aim of the study is to reveal the devolopment process of forestry policies and to reveal what has been done to ensure the protection of forests. When we look at the policies followed by the countries, it is seen that the world is now pursuing a conscious forestry policy.
اظهر المزيد [+] اقل [-]Nutritional Values of Partially Replacing the Commercial Soybean Meal by Raw, Full-Fat Soybean in Diets of Layers النص الكامل
2024
Mammo Mengesha Erdaw | Shambel Taye
The aim of this study was to investigating the effects of partially replacing the commercial soybean meal (SBM) by locally produced raw, full-fat soybean (RFFSB) in diets of layers. After cleaning, the tested ingredient (RFFSB) was hammered to pass through a 0.2-mm sieve. Then, four experimental diets were formulated by replacing the SBM by RFFSB at 0, 15, 30 or 45% (equivalents to 0, 30, 60 or 90 g/kg of diet, respectively). Before the commencement of this feeding trial, birds were uniformly managed and fed as per their requirements (i.e., starter, grower and pullet diets). This feeding trial was started when birds’ age was 24 weeks. Every treatment was replicated 4 times and 17 laying birds per replicate. The results revealed that replacing the commercial SBM by raw soybean (up to 45%) in the layer diets had no negative effects on the final live BWT and also on the vital organ developments, such as pancreas, duodenum, intestines and gizzard. Hen-day egg production, hen-housed egg production and egg quality measuring parameters were not significant affected by that of partially replacing the commercially SBM by the raw soybean. It is concluded that without compromising the productivity and health, a hammered RFFSB can replace (up to 45%) the commercial SBM in diets of the laying hens.
اظهر المزيد [+] اقل [-]Effects of 5-Aminolevulinic Acid (5-ALA) on Morphological and Physiological Characteristics of Grapevine against Salt Stress النص الكامل
2024
Selda Daler | Yılmaz Özkol
Salinity, one of the most significant abiotic stress factors restricting plant production, causes the destruction of agricultural lands and reduces productivity. In recent years, the utilization of 5-aminolevulinic acid (5-ALA) applications, which have important effects in terms of avoiding and providing tolerance to factors by impacting the physiology and metabolism of the plants, has been on the agenda. In this research, the impacts of foliar treatments of different levels of 5-ALA (0, 0.3, 0.6 and 0.9 mM) on morphological and physiological traits of 41 B American grapevine rootstocks under salinity stress (NaCl solution starting with 25 mM and reaching 150 mM concentration) were investigated. Salinity stress caused significant decreases in growth parameters, chlorophyll content, RWC and stomatal conductance, and significant increases in leaf temperature, proline and MDA content, physical damage and membrane damage degree. Under salinity stress, 0.9 mM 5-ALA treatments resulted in significant increases in shoot length (14.67 cm), root length (34.50 cm), leaf thickness (0.23 µm) leaf area (31.37 cm2), leaf number (8.67 pieces), chlorophyll content (21.83 SPAD), RWC (80.20%), proline content (0.19 μmol.g-1) and stomatal conductance (78.05 mmol.m-2.s-1); and significant decreases in physical damage degree (1.00 scale degree), membrane injury degree (15.46%) and MDA content (28.20 nmol.g-1) compared to non-ALA treatments. According to the results of this study, 5-ALA can be recommended as an alternative application to provide salinity tolerance in plants in order to reduce the damage caused by salinity stress in agricultural lands.
اظهر المزيد [+] اقل [-]Tarım İşletmecilerinin Çevresel Sürdürülebilirlik Algısı ve Düzeyi النص الكامل
2024
Ender Kaya | Zeki Bayramoğlu
Bu araştırmada tarım işletmelerinin sürdürülebilirlik algısının ve düzeyinin belirlenmesi amaçlanmıştır. Araştırma alanı olarak Konya ilinin seçilmesinde Türkiye genelinde önemli tarımsal üretim merkezlerinden biri olması belirleyici olmuştur. Çalışmanın kapsamında tabakalı tesadüfi örnekleme yöntemi kullanılmıştır. Toplamda 268 tarımsal işletme sahibiyle yüz yüze görüşülerek anket verileri derlenmiştir. Çevresel sürdürülebilirlik algı indeksinin hesaplanması için literatür verileri dikkate alınarak sürdürülebilirlik algı indeksi oluşturulmuştur. Araştırmada katılımcıların sürdürülebilirlik algıları beşli likert tipindeki ölçekle aldığı toplam puan alabileceği maksimum toplam puana oranlanarak “Sürdürülebilirlik Algı İndeksi” hesaplanmıştır. Çevresel sürdürülebilirlik düzeylerinin (uygulama/kullanma) tespit edilmesi için işletmecilerin sürdürülebilirlik düzey durumları anket verileri ile elde edilmiş olup toplam puan alabileceği maksimum puana oranlanarak “sürdürülebilirlik Düzey İndeksi” hesaplanmıştır. Birinci grupta yer alan işletmelerde sürdürülebilirlik algı indeks puanı %83,67, bu oran ikinci grupta %84,77, üçüncü grupta %89,39 ve dördüncü grupta %88,67 olarak belirlenmiştir. İşletmeler ortalaması sürdürülebilirlik indeks puanı %86,62 olarak belirlenmiştir. İşletme ölçeği büyüdükçe sürdürülebilirlik algı indeksi de artmaktadır. Araştırma sonuçlarına göre sürdürülebilirlik algı ve düzey indeksleri işletmeler ortalamasında karşılaştırıldığında sürdürülebilirlik düzey indeksinin %67,59 algı indeksinin ise %86,62 olduğu görülmektedir. Tarım işletmecilerinde sürdürülebildik algı indeksinin yüksek olması sürdürülebilirlikle ilgili konularda algılarının olduğunu fakat düzey (uygulama/kullanma) yetersiz kaldıkları görülmektedir. Tarım işletmecilerinin bilinç düzeylerinin artırılması ve eyleme geçirmek adına eğitim ve yayım çalışmalarına ağırlık verilmelidir.
اظهر المزيد [+] اقل [-]Yonca Silajlarına Defne (Laurus nobilis L.) Yaprağı Tozu İlavesinin Silaj Kalitesine ve In vitro Gaz Üretim Parametrelerine Etkisi النص الكامل
2024
Metin Duru
Bu çalışma, farklı düzeylerde defne (Laurus nobilis L.) yaprağı tozu (DYT) katkısının yonca silajlarında kimyasal kompozisyonun, in vitro gaz üretim parametrelerinin (metabolize edilebilir enerji, in vitro organik madde sindirilebilirliği ve net enerji laktasyonu) ve bazı fermentasyon özelliklerinin belirlenmesi amacıyla yapılmıştır. Defne yaprağı tozu, yoncaya %0 (kontrol), %0,5 (DYT05), %1,0 (DYT10), %1,5 (DYT15), %2,0 (DYT20), %4,0 (DYT40) ve %8,0 (DYT80) düzeylerinde ilave edilerek 75 gün boyunca silolanmıştır. Araştırma sonunda, kontrol grubuna göre DYT05 grubunda yonca silajının kuru madde içeriği azalmış, DYT20, DYT40 ve DYT80 gruplarında ise kuru madde içeriği artmıştır. DYT80 grubunda ham kül içeriği düşük bulunmuştur. DYT10 ve daha yüksek düzeyler silajın pH’sını; DYT20 ve daha yüksek düzeylerse laktik asit içeriğini önemli düzeyde düşürmüştür. Defne yaprağı muamelesi, silajların NDF, ADF, ham protein, ham yağ, asetik asit, propiyonik asit, in vitro gaz üretim parametrelerini etkilememiştir. Araştırma silajlarının tamamında bütirik asit ve amonyak azot içeriği tespit edilmemiştir. Sonuç olarak, DYT’nin yonca silajlarında %1 düzeyinde kullanılabileceği ve pozitif katkısının olabileceği sonucuna varılmıştır.
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