28 research outputs found
Classification of olive oils using chromatography, principal component analysis and artificial neural network modelling
WOS: 000431327000067Classification and addressing, and geographical origin of different olive oils is of great importance due to their differentiation in quality, and for commercial concerns. In this study, quantification of sterols, fatty acids, and triacylglycerol composition of forty-nine olive oils collected from six different locations of western part of Turkey (Izmir, Manisa, Aydm, Mugla, Bursa, and Edremit Bay) were performed by using chromatographic methods. Data for those olive oil samples were compiled, and classified with the artificial neural network (ANN) modelling and principal components analysis (PCA). The analytical results included resourceful information about determining geographical origin and traceability of olive oil in Turkey by using ANN and PCA. The ANN model for sterol composition showed the highest accuracy with 85.71%. The FAME and TAG profiles followed this with 83.67 and 81.63% accuracy respectively. However, Izmir and Manisa regions have poor sensitivity values with all ANN models since they are geographically very close to each other. Furthermore, the PCA results of the sterol composition have provided separation and clustering between locations. beta-sitosterol, campesterol, stigmasterol and 24-metilen cholesterol have an important role in determining the separation of the locations of origin. While separation of the Bursa location has been under the pressure of FAME composition, the TAGs have been effective on the clustering of the Aydm and Edremit Bay. In conclusion, the geographical authentication of Turkish olive oils can be done with high accuracy by using ANN and PCA.EGE University Drug Research and Pharmacokinetic Development and Applied Center, ARGEFAR; Ege University Research FundEge University [14-MUH-063 BAP]This work was supported by EGE University Drug Research and Pharmacokinetic Development and Applied Center, ARGEFAR. Artificial Neural Networks part of this study was supported by Ege University Research Fund through the 14-MUH-063 BAP project
Sample Preparation Methods for Metal Containing Pesticides in Food and Environmental Samples
Metal-containing pesticides are used in many areas for purposes such as harvest efficiency and keeping pests away from the vegetable environment. Metal-containing pesticides are in the form of dithiocarbamate complexes and are named differently according to the type of metal they contain and are used for different purposes. Since the presence of these pesticides even at residue level threatens human and environmental health, their determination at trace level is important. In this review, studies on the determination of metal-containing dithiocarbamate pesticides in different matrices are discussed. This review on the analysis of dithiocarbamate pesticides with different techniques will shed light on the studies to be carried out for the determination of these pesticides one by one in different matrices.The authors are grateful for the financial support of the Unit of the Scientific Research Projects of Erciyes University (FBG-2020-10013) (Kayseri, Turkey). Dr. Mustafa Soylak thanks to Turkish Academy of Sciences (TUBA) for financial support.Unit of the Scientific Research Projects of Erciyes University [FBG-2020-10013]; Turkish Academy of Sciences (TUBA
Sample Preparation Methods for Metal Containing Pesticides in Food and Environmental Samples
Metal-containing pesticides are used in many areas for purposes such as harvest efficiency and keeping pests away from the vegetable environment. Metal-containing pesticides are in the form of dithiocarbamate complexes and are named differently according to the type of metal they contain and are used for different purposes. Since the presence of these pesticides even at residue level threatens human and environmental health, their determination at trace level is important. In this review, studies on the determination of metal-containing dithiocarbamate pesticides in different matrices are discussed. This review on the analysis of dithiocarbamate pesticides with different techniques will shed light on the studies to be carried out for the determination of these pesticides one by one in different matrices
Magnetic solid-phase extraction of atrazine with ACC@NiCo<sub>2</sub>O<sub>4</sub>@Fe<sub>3</sub>O<sub>4</sub> nanocomposite in spice and water samples
A simple, environmentally friendly, effective and selective magnetic solid-phase extraction method (MSPE) has been developed for the separation and quantitative determination of atrazine from spices and water samples before liquid chromatographic (LC) analysis. Activated carbon cloth@NiCo2O4@Fe3O4 was characterized by Fourier transform infrared spectroscopy (FT-IR), X-ray photoelectron spectroscopy (XPS), X-ray diffraction spectrometry (XRD), Brunauer–Emmett–Teller (BET), and scanning electron microscopy with energy distribution X-Ray detector (SEM-EDX) techniques. The developed MSPE-LC procedure was optimized in terms of pH, adsorbent amount, adsorption time, eluent type and volume, interference parameters and the pre-concentration factor and extraction efficiency at optimum conditions were determined. In the determination of atrazine, it was observed that the activated carbon cloth@NiCo2O4@Fe3O4 nanocomposite could be reused at least 25 times by applying the adsorption-desorption cycle. According to best extraction efficiency of parameters for the extraction and determination of atrazine from spices and water samples were determined as pH 7, adsorbent amount of 0 mg, total adsorption-desorption time of 5 minutes, and enrichment factor of 20. The recovery values of the magnetic solid-phase extraction method in spices and water samples under optimum conditions are between 91% and 94%. Analysis of trace levels of atrazine, limit of detection (LOD) and limit of quantification (LOQ) were determined by HPLC-DAD method with 0.5 ng mL−1 and 1.7 ng mL−1, respectively. Sample applications with high recovery values performed with the MSPE-LC method were confirmed by liquid chromatography quadrupole time-of-flight mass spectrometry (LC-Q-TOF/MS) for spices and water samples.</p
Cycling Dof Factors: Molecular and functional characterization of Arabidopsis thaliana AtCDF3 and tomato (Solanum lycopersicum L.) SlCDF3 in response to abiotic stress
El tomate (Solanum lycopersicum L.) es considerado uno de los cultivos hortÃcolas de mayor importancia económica en el territorio Español. Sin embargo, su producción está seriamente afectada por condiciones ambientales adversas como, salinidad, sequÃa y temperaturas extremas. Para resolver los problemas que se presentan en condiciones de estrés, se han empleado una serie de técnicas culturales que disminuyen sus efectos negativos, siendo de gran interés el desarrollo de variedades tolerantes. En este sentido la obtención y análisis de plantas transgénicas, ha supuesto un avance tecnológico, que ha facilitado el estudio y la evaluación de genes seleccionados en relación con la tolerancia al estrés. Estudios recientes han mostrado que el uso de genes reguladores como factores de transcripción (FTs) es una gran herramienta para obtener nuevas variedades de tomate con mayor tolerancia a estreses abióticos. Las proteÃnas DOF (DNA binding with One Finger) son una familia de FTs especÃfica de plantas (Yangisawa, 2002), que están involucrados en procesos fisiológicos exclusivos de plantas como: asimilación del nitrógeno y fijación del carbono fotosintético, germinación de semilla, metabolismo secundario y respuesta al fotoperiodo pero su preciso rol en la tolerancia a estrés abiótico se desconoce en gran parte. El trabajo descrito en esta tesis tiene como objetivo estudiar genes reguladores tipo DOF para incrementar la tolerancia a estrés abiotico tanto en especies modelo como en tomate. En el primer capÃtulo de esta tesis se muestra la caracterización funcional del gen CDF3 de Arabidopsis, asà como su papel en la respuesta a estrés abiótico y otros procesos del desarrollo. La expresión del gen AtCDF3 es altamente inducido por sequÃa, temperaturas extremas, salinidad y tratamientos con ácido abscÃsico (ABA). La lÃnea de inserción T-DNA cdf3-1 es más sensible al estrés por sequÃa y bajas temperaturas, mientras que lÃneas transgénicas de Arabidopsis 35S::AtCDF3 aumentan la tolerancia al estrés por sequÃa, osmótico y bajas temperaturas en comparación con plantas wild-type (WT). Además, estas plantas presentan un incremento en la tasa fotosintética y apertura estomática. El gen AtCDF3 se localiza en el núcleo y que muestran una unión especÃfica al ADN con diferente afinidad a secuencias diana y presentan diversas capacidades de activación transcripcional en ensayos de protoplastos de Arabidopsis. El dominio C-terminal de AtCDF3 es esencial para esta localización y su capacidad activación, la delección de este dominio reduce la tolerancia a sequÃa en plantas transgénicas 35S::AtCDF3. Análisis por microarray revelan que el AtCDF3 regula un set de genes involucrados en el metabolismo del carbono y nitrógeno. Nuestros resultados demuestran que el gen AtCDF3 juega un doble papel en la regulación de la respuesta a estrés por sequÃa y bajas temperaturas y en el control del tiempo de floración. En el segundo capÃtulo de este trabajo se lleva a cabo la identificación de 34 genes Dof en tomate que se pueden clasificar en base a homologÃa de secuencia en cuatro grupos A-D, similares a los descritos en Arabidopsis. Dentro del grupo D se han identificado cinco genes DOF que presentan caracterÃsticas similares a los Cycling Dof Factors (CDFs) de Arabidopsis. Estos genes son considerados ortólogos de Arabidopsis CDF1-5, y han sido nombrados como Solanum lycopersicum CDFs o SlCDFs. Los SlCDF1-5 son proteÃnas nucleares que muestran una unión especÃfica al ADN con diferente afinidad a secuencias diana y presentan diversas capacidades de activación transcripcional in vivo. Análisis de expresión de los genes SlCDF1-5 muestran diferentes patrones de expresión durante el dÃa y son inducidos de forma diferente en respuesta a estrés osmótico, salino, y de altas y bajas temperaturas. Plantas de Arabidopsis que sobre-expresan SlCDF1 y SlCDF3 muestran un incremento de la tolerancia a la sequÃa y salinidad. Además, de la expresión de varios genes de respuesta estrés como AtCOR15, AtRD29A y AtERD10, son expresados de forma diferente en estas lÃneas. La sobre-expresión de SlCDF3 en Arabidopsis promueve un retardo en el tiempo de floración a través de la modulación de la expresión de genes que controlan la floración como CONSTANS (CO) y FLOWERING LOCUS T (FT). En general, nuestros datos demuestran que los SlCDFs están asociados a funciones aun no descritas, relacionadas con la tolerancia a estrés abiótico y el control del tiempo de floración a través de la regulación de genes especÃficos y a un aumento de metabolitos particulares. ABSTRACT Tomato (Solanum lycopersicum L.) is one of the horticultural crops of major economic importance in the Spanish territory. However, its production is being affected by adverse environmental conditions such as salinity, drought and extreme temperatures. To resolve the problems triggered by stress conditions, a number of agricultural techniques that reduce the negative effects of stress are being frequently applied. However, the development of stress tolerant varieties is of a great interest. In this direction, the technological progress in obtaining and analysis of transgenic plants facilitated the study and evaluation of selected genes in relation to stress tolerance. Recent studies have shown that a use of regulatory genes such as transcription factors (TFs) is a great tool to obtain new tomato varieties with greater tolerance to abiotic stresses. The DOF (DNA binding with One Finger) proteins form a family of plant-specific TFs (Yangisawa, 2002) that are involved in the regulation of particular plant processes such as nitrogen assimilation, photosynthetic carbon fixation, seed germination, secondary metabolism and flowering time bur their precise roles in abiotic stress tolerance are largely unknown. The work described in this thesis aims at the study of the DOF type regulatory genes to increase tolerance to abiotic stress in both model species and the tomato. In the first chapter of this thesis, we present molecular characterization of the Arabidopsis CDF3 gene as well as its role in the response to abiotic stress and in other developmental processes. AtCDF3 is highly induced by drought, extreme temperatures, salt and abscisic acid (ABA) treatments. The cdf3-1 T-DNA insertion mutant was more sensitive to drought and low temperature stresses, whereas the AtCDF3 overexpression enhanced the tolerance of transgenic plants to drought, cold and osmotic stress comparing to the wild-type (WT) plants. In addition, these plants exhibit increased photosynthesis rates and stomatal aperture. AtCDF3 is localized in the nuclear region, displays specific binding to the canonical DNA target sequences and has a transcriptional activation activity in Arabidopsis protoplast assays. In addition, the C-terminal domain of AtCDF3 is essential for its localization and activation capabilities and the deletion of this domain significantly reduces the tolerance to drought in transgenic 35S::AtCDF3 overexpressing plants. Microarray analysis revealed that AtCDF3 regulated a set of genes involved in nitrogen and carbon metabolism. Our results demonstrate that AtCDF3 plays dual roles in regulating plant responses to drought and low temperature stress and in control of flowering time in vegetative tissues. In the second chapter this work, we carried out to identification of 34 tomato DOF genes that were classified by sequence similarity into four groups A-D, similar to the situation in Arabidopsis. In the D group we have identified five DOF genes that show similar characteristics to the Cycling Dof Factors (CDFs) of Arabidopsis. These genes were considered orthologous to the Arabidopsis CDF1 - 5 and were named Solanum lycopersicum CDFs or SlCDFs. SlCDF1-5 are nuclear proteins that display specific binding to canonical DNA target sequences and have transcriptional activation capacities in vivo. Expression analysis of SlCDF1-5 genes showed distinct diurnal expression patterns and were differentially induced in response to osmotic, salt and low and high temperature stresses. Arabidopsis plants overexpressing SlCDF1 and SlCDF3 showed increased drought and salt tolerance. In addition, various stress-responsive genes, such as AtCOR15, AtRD29A and AtERD10, were expressed differently in these lines. The overexpression of SlCDF3 in Arabidopsis also results in the late flowering phenotype through the modulation of the expression of flowering control genes such CONSTANS (CO) and FLOWERING LOCUS T (FT). Overall, our data connet SlCDFs to undescribed functions related to abiotic stress tolerance and flowering time through the regulation of specific target genes and an increase in particular metabolites
Analysis of Chemical Compositions of 15 Different Cold-Pressed Oils Produced in Turkey: A Case Study of Tocopherol and Fatty Acid Analysis
Many people tend to prefer natural foods and supplements nowadays. Considering this tendency, this study assessed the most significant in quality and purity parameters tocopherol and fatty acid compositions of cold-pressed oils, namely black cumin, sesame, sunflower, poppy, pomegranate, nettle, pumpkin, grape, safflower, flax, canola seed, wheat germ, peanut, hazelnut, and walnut. This study deals with the sample preparation and validation of tocopherols using an HPLC-FLD method for simultaneous determination of α-β-γ-, and δ-tocopherols, and analysis of fatty acid methyl esters (FAME) with using GC-FID. The validated HPLC method was applied for the tocopherols’ analysis and measurement uncertainty was calculated for tocopherols and some fatty acids. The obtained data were evaluated by using principal component analysis to show the relationship between quality parameters and seed oils. Wheat germ, hazelnut, safflower, and sunflower oils have the highest tocopherol contents respectively with a predominance of α-tocopherol. Seed oils’ fatty acid compositions were classified according to proportions of oleic, linoleic, and other fatty acids. This study shows that the evaluated seeds are valuable sources of natural antioxidants and some specific and polyunsaturated fatty acids. The applied method can also be helpful for the industry to obtain quality analysis approach
Sensor Platform with a Custom-Tailored Aptamer for Diagnosis of Synthetic Cannabinoids
Ceylan, Ayse Elcin/0000-0002-0591-6080; Evran, Serap/0000-0001-6676-4888; BALABAN, Simge/0000-0002-4540-1882WOS: 000505868000001Synthetic cannabinoids (SCs) are the large group of abused drugs and detection of them is still a challenge. Hence, new methods for analysis of SCs are being investigated. We aimed to develop a novel system for selective analysis of SCs. First, various custom-tailored aptamers against the target SCs were selected through GO-SELEX process. Toggling between different SC analytes during successive rounds of selection was performed to generate cross-reactive aptamers. Then, the amino-capped aptamers were synthesized and easily attached to the cysteamine-covered gold electrodes. Analytical parameters and selectivity of the aptasensors were compared by using electrochemical techniques. After comparison of the analytical features and selectivity towards target analytes, one of the aptamers designated as Apta-1 was chosen for further measurements. the aptasensor was tested by using differential pulse voltammetry technique against JWH-018 (5-pentanoic acid), selected as a model for SCs. the linearity and limit of detection were determined as 0.01-1.0 ng/mL and 0.036 ng/mL. Finally, sample application in synthetic urine samples was successfully performed with standard addition method, as confirmed by LC-QTOF/MS. JWH-018 (4-hydroxypentyl), JWH-073 (3-hydroxybutyl), JWH-250 (5-hidroxypentyl) and HU-210 were used to test the selectivity of the aptasensor and the system was shown to recognize all these SCs. Also other illegal drugs did not significantly interfere with the signal responses.Scientific and Technological Research Council of Turkey (TUBITAK)Turkiye Bilimsel ve Teknolojik Arastirma Kurumu (TUBITAK) [117Z152]; Republic of Turkey, Ministry of DevelopmentTurkiye Cumhuriyeti Kalkinma Bakanligi [2016K121190]; Ege University Central Research Testing and Analysis Laboratory Research and Application Center (EGE-MATAL)This study was supported by the Scientific and Technological Research Council of Turkey (TUBITAK, Project Grant No: 117Z152). This work was also supported by Republic of Turkey, Ministry of Development (Project Grant No: 2016K121190) and Ege University Central Research Testing and Analysis Laboratory Research and Application Center (EGE-MATAL) chromatography laboratories were used in this study