Biological degradation of glyphosate

La necesidad de producir más alimentos ha llevado al aumento del uso de pesticidas, entre ellos glifosato, el cual es ampliamente empleado en la producción de soja transgénica. Esto ha implicado que crezcan los casos de intoxicaciones y contaminación de recursos naturales. Por tal motivo los entes gubernamentales han formulado instrucciones de manipulación y de descarte de los envases comerciales. El objetivo del presente trabajo fue evaluar la capacidad de Candida tropicalis LMFIQ 703 para disminuir la concentración de glifosato en el tercer enjuague de bidones y así reducir el riesgo de impacto ambiental adverso que producen los residuos de pesticida en los envases vacíos almacenados por largos periodos de tiempo. Se sembraron suspensiones de levadura sin adaptación, en soluciones de Credit® Amonio (Ingrediente activo: sal amónica de la N-fosfonometil glicina) con concentración conocida (similar a la del tercer enjuague). Se incubó a 28°C durante 28 días y se realizó el recuento microbiológico de colonias de levadura cada 7 días. La determinación de la concentración de glifosato se hizo por fluorimetría con calibración multivariada y HPLC. Las levaduras se mantuvieron viables durante todo el experimento, con una disminución inicial por adaptación y una concentración final similar a la inicial. Los resultados de la cuantificación de glifosato a través de fluorescencia y calibración multivariada, aprovechando la ventaja de segundo orden del algoritmo MCR-ALS resultaron comparables con los obtenidos por el método de referencia (HPLC). Se puede concluir que la biorremediación propuesta fue eficiente ya que la concentración de glifosato disminuyó un 39%.The need to produce more food has led to an increased usage of pesticides. One of them is glyphosate, which is widely used in soybean production. This has implied the growing of cases of intoxication and pollution of natural resource. For this reason, government agencies have formulated instructions for handling and disposal of commercial packaging. The aim of the present work was to evaluate the ability of the yeast Candida tropicalis LMFIQ 703 to decrease the concentration of glyphosate present in the third rinse of the containers, so as to diminish the risk of adverse ambient impact produced by the pesticide residues in empty containers stored for long periods of time. Yeast suspensions were seeded, without adaptation, in Credit Ammonium solutions (Active ingredient: ammonium salt of N-phosphonomethyl glycine) of known concentration (similar to the obtained in the third rinse). The incubation was done at 28 °C for 28 days. Glyphosate was quantified and the number of colonies was determined at different times. The concentration of the pesticide was done by a fluorimetric method with multivariate calibration as well as by HPLC. Yeasts remained viable throughout the experiment, with an initial decrease because of adaptation and a final concentration similar to the initial. The quantification results of glyphosate by the fluorimetric technique with the aid of the second order advantage achieved by MCR-ALS were comparable with those acquired by the reference method (HPLC). It can be concluded that the proposed bioremediation is efficient since the concentration of glyphosate was decreased by 39%.Fil: Sobrero, María Silvina. Universidad Nacional del Litoral. Facultad de Bioquímica y Ciencias Biológicas; ArgentinaFil: Marsili, Nilda Raquel. Universidad Nacional del Litoral. Facultad de Bioquímica y Ciencias Biológicas; ArgentinaFil: Schenone, Agustina Violeta. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Desarrollo Tecnológico para la Industria Química. Universidad Nacional del Litoral. Instituto de Desarrollo Tecnológico para la Industria Química; ArgentinaFil: Manzo, Ricardo Martín. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Desarrollo Tecnológico para la Industria Química. Universidad Nacional del Litoral. Instituto de Desarrollo Tecnológico para la Industria Química; ArgentinaFil: Frisón, Laura Noemí. Universidad Nacional del Litoral. Facultad de Ingeniería Química. Departamento de Ingeniería en Alimento. Area de Biotecnología; Argentin

Determination of Mycotoxins in Food with the Aid of Chemometric Tools

This chapter presents an overview of current chemometric tools utilized for the evaluation of several mycotoxins often found in foodstuff, such as cereals, peanuts, pistachio nuts and condiments. Mycotoxins are compounds produced as a result of the secondary metabolism of fungus, such as Aspergillus, Fusarium and Penicillium. Because of their harmful effect in animals and humans, their levels in food are strictly controlled.Discussions are focused on the analysis of first and second-order data generated through several techniques such as near infrared spectroscopy, fluorescence spectroscopy and high performance liquid chromatography with diode array detector. This review manuscript describes the algorithms frequently used to model this type of data, including Partial Least Squares (PLS) regression, Parallel Factor Analysis (PARAFAC) and Multivariate Curve Resolution Alternating Least Squares (MCR-ALS). These multivariate calibration methods allow the quantification of multiple analytes in complex food samples with the application of minimum pre-treatment techniques. Another important chemometric tool commented in this review is the Response Surface Method (RSM), commonly applied in the optimization of experimental procedures and chemical measurements.This chapter discusses the different strategies implemented for the analysis of a wide spectrum of mycotoxins, as well as their advantages and disadvantages.Fil: Schenone, Agustina Violeta. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Desarrollo Tecnológico para la Industria Química. Universidad Nacional del Litoral. Instituto de Desarrollo Tecnológico para la Industria Química; ArgentinaFil: Marsili, Nilda Raquel. Universidad Nacional del Litoral. Facultad de Bioquímica y Ciencias Biológicas; Argentin

Determination of tartrazine in beverage samples by stopped-flow analysis and three-way multivariate calibration of non-linear kinetic-spectrophotometric data

The performance of MCR-ALS was studied in the modeling of non-linear kinetic-spectrophotometric data acquired by a stopped-flow system for the quantitation of tartrazine in the presence of brilliant blue and sunset yellow FCF as possible interferents. In the present work, MCR-ALS and U-PCA/RBL were firstly applied to remove the contribution of unexpected components not included in the calibration set. Secondly, a polynomial function was used to model the non-linear data obtained by the implementation of the algorithms. MCR-ALS was the only strategy that allowed the determination of tartrazine in test samples accurately. Therefore, it was applied for the analysis of tartrazine in beverage samples with minimum sample preparation and short analysis time. The proposed method was validated by comparison with a chromatographic procedure published in the literature. Mean recovery values between 98% and 100% and relative errors of prediction values between 4% and 9% were indicative of the good performance of the method.Fil: Schenone, Agustina Violeta. Universidad Nacional del Litoral. Facultad de Bioquímica y Ciencias Biológicas. Departamento de Química. Cátedra de Química Analítica; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe; ArgentinaFil: Culzoni, Maria Julia. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe; Argentina. Universidad Nacional del Litoral. Facultad de Bioquímica y Ciencias Biológicas. Departamento de Química. Cátedra de Química Analítica; ArgentinaFil: Marsili, Nilda Raquel. Universidad Nacional del Litoral. Facultad de Bioquímica y Ciencias Biológicas. Departamento de Química. Cátedra de Química Analítica; ArgentinaFil: Goicoechea, Hector Casimiro. Universidad Nacional del Litoral. Facultad de Bioquímica y Ciencias Biológicas. Departamento de Química. Cátedra de Química Analítica; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe; Argentin

Identification and quantification of sugars by micellarelectrokinetic chromatography in reverse phase in modified milk

Se desarrolló un método por electroforesis electrocinética micelar para la determinación simultánea de glucosa, fructosa, lactosa y sacarosa en leches modificadas. La separación de los componentes estudiados se llevó a cabo utilizando capilares de sílice, bromuro de cetiltrimetilamonio (CTAB) como surfactante catiónico en el electrolito de corrida, polaridad reversa y detección UV indirecta. Las curvas de calibración fueron lineales con R2 > 98,49. La desviación estándar relativa (RSD%) en todos los casos fue menor a 1,88% y la recuperación fue entre 95-114% para la glucosa, 104-110% para la fructosa, 93-113% para la lactosa y 92-110% para la sacarosa. El método analítico propuesto presenta una buena separación de los analitos, implica pretratamiento sencillo de las muestras y genera bajos volúmenes de desecho. La precisión, exactitud y rapidez, hacen que sea un método útil para la cuantificación simultánea de azúcares en leches modificadas.A method by micellarelectrokinetic electrophoresis for the simultaneous determination of glucose, fructose, lactose and sucrose in modified milks was developed. Separation of the compounds studied was carried out using fused silica capillaries, cetyltrimethylammonium bromide (CTAB) as cationic surfactant in run electrolyte, reverse polarity and indirect UV detection. Calibration curves were linear with R2> 98.49. The relative standard deviation (RSD %) in all cases was less than 1.88 % and the recovery was between 95–114 % for glucose, 104–110 % for fructose, 93–113 % for lactose and 92–110 % for sucrose. The analytical method developed provides good separation of the analytes, involves simple pretreatment of samples and low volumes of waste generated. The precision, accuracy and speed of the method, make it a useful tool for the simultaneous quantification of modified milk sugars.Fil: Gerstner, Carolina Daniela. Universidad Nacional del Litoral. Facultad de Bioquímica y Ciencias Biológicas. Departamento de Ciencias Biológicas. Cátedra de Bromatología y Nutrición; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe; ArgentinaFil: Bernal, Claudio Adrian. Universidad Nacional del Litoral. Facultad de Bioquímica y Ciencias Biológicas. Departamento de Ciencias Biológicas. Cátedra de Bromatología y Nutrición; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe; ArgentinaFil: Marsili, Nilda Raquel. Universidad Nacional del Litoral. Facultad de Bioquímica y Ciencias Biológicas; ArgentinaFil: Maccari, M.. La Sibila SA; ArgentinaFil: Williner, María Rosa. Universidad Nacional del Litoral. Facultad de Bioquímica y Ciencias Biológicas. Departamento de Ciencias Biológicas. Cátedra de Bromatología y Nutrición; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe; Argentin

New Method for the Determination of Benzoic and Sorbic Acids in Commercial Orange Juices based on Second-Order Spectrophotometric Data Generated by a pH Gradient Flow Injection Technique

Two widely employed antimicrobials, benzoic and sorbic acids, were simultaneously determined in commercial orange juices employing a combination of a flow injection system with pH gradient generation, diode array spectrophotometric detection, and chemometric processing of the recorded second-order data. Parallel factor analysis and multivariate curve resolution-alternating least-squares were used for obtaining the spectral profiles of sample components and concentration profiles as a function of pH, including provisions for managing rank-deficient data sets. An appropriately designed calibration with a nine-sample set of binary mixtures of standards, coupled to the use of the second-order advantage offered by the applied chemometric techniques, allowed quantitation of the analytes in synthetic test samples and also in commercial orange juices, even in the presence of unmodeled interferents (with relative prediction errors of 8.7% for benzoic acid and 2.5% for sorbic acid). No prior separation or sample pretreatment steps were required. The comparison of results concerning commercial samples with a laborious reference technique yielded satisfactory statistical indicators (recoveries were 99.0% for benzoic acid and 101.4% for sorbic acid).Fil: Marsili, Nilda Raquel. Universidad Nacional del Litoral; ArgentinaFil: Lista, Adriana Guillermina. Universidad Nacional del Sur; ArgentinaFil: Fernández Band, Beatriz Susana. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Nacional del Sur; ArgentinaFil: Goicoechea, Hector Casimiro. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. North Dakota State University; Estados Unidos. Universidad Nacional del Litoral; ArgentinaFil: Olivieri, Alejandro Cesar. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Rosario; Argentina. Universidad Nacional de Rosario; Argentin

Evaluation of complex spectral-pH three-way arrays by modified bilinear least-squares: Determination of four different dyes in interfering systems

This article reports on the first application of a modified version of the bilinear least-squares model to absorbance-pH second-order data recorded for complex samples. The latter are composed of fruit drink powders, where four different analytes and additional background components occur. The analytes are the common juice colorants tartrazine, yellow sunset, allura red and indigo carmine. The data have been measured after generating a double pH gradient within a flow injection system. The selected chemometric methodology adequately exploits the second-order advantage, needed to take into account the background interferents present in real samples. Due to severe spectral overlapping between the acid and basic forms of each of the colorants in the working pH range, other second-order multivariate calibration methods such as parallel factor analysis and multivariate curve resolution-alternating least-squares could not be successfully applied to the presently studied samples. Recoveries of 94.8, 104.7, 109.3 and 105.3% were obtained for yellow sunset, indigo carmine, allura red and tartrazine respectively in the real test samples.Fil: Marsili, Nilda Raquel. Universidad Nacional del Litoral. Facultad de Bioquímica y Ciencias Biológicas; ArgentinaFil: Lista, Adriana Guillermina. Universidad Nacional del Sur; ArgentinaFil: Fernández Band, Beatriz Susana. Universidad Nacional del Sur; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Bahía Blanca. Instituto de Química del Sur. Universidad Nacional del Sur. Departamento de Química. Instituto de Química del Sur; ArgentinaFil: Goicoechea, Hector Casimiro. Universidad Nacional del Litoral. Facultad de Bioquímica y Ciencias Biológicas; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Olivieri, Alejandro Cesar. Universidad Nacional de Rosario. Facultad de Ciencias Bioquímicas y Farmacéuticas; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Rosario; Argentin

A novel fluorimetric method for glyphosate and AMPA determination with NBD-Cl and MCR-ALS

We report the development of a new analytical method for the quantification of N-(phosphonomethyl)glycine (glyphosate) and (aminomethyl)phosphonic acid (AMPA) by combining spectrofluorimetry and multivariate calibration. In this study, fluorescence spectroscopy was used to quantify glyphosate and AMPA, which were previously derivatized with the fluorogenic reagent: 4-chloro-7-nitrobenzofurazan (NBD-Cl). Fluorescence excitation-emission matrices (EEM) were recorded by exciting between 400 and 500 nm, and measuring the emission between 500 and 610 nm. The second-order data obtained were processed using the Multivariate Curve Resolution with Alternating Least Square (MCR-ALS) methodology. The developed method was used to predict different concentrations of glyphosate and AMPA in validation samples. In addition, the presence of the herbicide was evaluated in real samples: a commercial formulation and a water sample from a cultivated area. For this purpose, the standard addition method was used to study the matrix effect in each case. The ranges of working concentrations obtained for this new method are in agreement with the amounts found in surface water samples near a direct sowing soybean growing region in Argentina.Fil: Pérez, Ana Laura. Universidad Nacional del Litoral. Facultad de Bioquímica y Ciencias Biológicas. Departamento de Física; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Tibaldo, Giuliana. Universidad Nacional del Litoral. Facultad de Bioquímica y Ciencias Biológicas. Departamento de Química. Cátedra de Química Analítica; ArgentinaFil: Sánchez, Germán Hugo. Universidad de Buenos Aires. Facultad de Farmacia y Bioquímica. Centro de Investigación y Apoyo a la Educación Científica; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Nacional del Litoral. Facultad de Bioquímica y Ciencias Biológicas. Departamento de Química. Cátedra de Química General E Inorganica; ArgentinaFil: Siano, Gabriel German. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Nacional del Litoral. Facultad de Bioquímica y Ciencias Biológicas. Departamento de Química. Cátedra de Química Analítica; ArgentinaFil: Marsili, Nilda Raquel. Universidad Nacional del Litoral. Facultad de Bioquímica y Ciencias Biológicas. Departamento de Química. Cátedra de Química Analítica; ArgentinaFil: Schenone, Agustina Violeta. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Desarrollo Tecnológico para la Industria Química. Universidad Nacional del Litoral. Instituto de Desarrollo Tecnológico para la Industria Química; Argentina. Universidad Nacional del Litoral. Facultad de Bioquímica y Ciencias Biológicas. Departamento de Química. Cátedra de Química Analítica; Argentin

Second-order advantage from kinetic-spectroscopic data matrices in the presence of extreme spectral overlapping: A multivariate curve resolution, alternating least-squares approach.

Multivariate curve resolution coupled to alternating least-squares (MCR-ALS) has been employed to model kinetic-spectroscopic second-order data, with focus on the achievement of the important second-order advantage, under conditions of extreme spectral overlapping among sample components. A series of simulated examples shows that MCR-ALS can conveniently handle the studied analytical problem unlike other second-order multivariate calibration algorithms, provided matrix augmentation is implemented in the spectral mode instead of in the usual kinetic mode. The approach has also been applied to three experimental examples, which involve the determination of: (1) the antiparkinsonian carbidopa (analyte) in the presence of levodopa as a potential interferent, both reacting with cerium (IV) to produce the fluorescent species cerium (III) with different kinetics; (2) Fe(II) (analyte) in the presence of the interferent Zn(II), both catalyzing the oxidation of methyl orange with potassium bromate; and (3) tartrazine (analyte) in the presence of the interferent brilliant blue, both oxidized with potassium bromate, with the interferent leading to a product with an absorption spectrum very similar to tartrazine. The results indicate good analytical performance towards the analytes, despite the intense spectral overlapping and the presence of unexpected constituents in the test samples.Fil: Culzoni, Maria Julia. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe; Argentina. Universidad Nacional del Litoral. Facultad de Bioquímica y Ciencias Biológicas. Laboratorio de Desarrollo Analítico y Quimiometría; ArgentinaFil: Goicoechea, Hector Casimiro. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe; Argentina. Universidad Nacional del Litoral. Facultad de Bioquímica y Ciencias Biológicas. Laboratorio de Desarrollo Analítico y Quimiometría; ArgentinaFil: Ibañez, Gabriela Alejandra. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Rosario. Instituto de Química Rosario. Universidad Nacional de Rosario. Facultad de Ciencias Bioquímicas y Farmacéuticas. Instituto de Química Rosario; ArgentinaFil: Lozano, Valeria Antonella. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Rosario. Instituto de Química Rosario. Universidad Nacional de Rosario. Facultad de Ciencias Bioquímicas y Farmacéuticas. Instituto de Química Rosario; ArgentinaFil: Marsili, Nilda Raquel. Universidad Nacional del Litoral. Facultad de Bioquímica y Ciencias Biológicas. Laboratorio de Desarrollo Analítico y Quimiometría; ArgentinaFil: Olivieri, Alejandro Cesar. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Rosario. Instituto de Química Rosario. Universidad Nacional de Rosario. Facultad de Ciencias Bioquímicas y Farmacéuticas. Instituto de Química Rosario; ArgentinaFil: Pagani, Ariana Paula. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Rosario. Instituto de Química Rosario. Universidad Nacional de Rosario. Facultad de Ciencias Bioquímicas y Farmacéuticas. Instituto de Química Rosario; Argentin