The Experts below are selected from a list of 81 Experts worldwide ranked by ideXlab platform
Jaume Pérez-sánchez - One of the best experts on this subject based on the ideXlab platform.
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Gas chromatography-mass spectrometric determination of polybrominated diphenyl ethers in complex fatty matrices from aquaculture activities.
Analytica chimica acta, 2010Co-Authors: Jaime Nácher-mestre, Roque Serrano, Félix Hernández, Laura Benedito-palos, Jaume Pérez-sánchezAbstract:Abstract Gas chromatography coupled to mass spectrometry in negative chemical ionization mode (GC–(NCI)MS) has been applied to the quantification and reliable identification of polybrominated diphenyl ethers (PBDEs) in animal and vegetable samples from aquaculture activities. Matrices analyzed included Fish Fillet, Fish feed, Fish oil and linseed oil, their fat content ranged from 5% to 100%. Solid-phase extraction (SPE) (using Florisil and silica cartridges) and normal-phase high performance liquid chromatography were tested for an efficient clean-up in order to obtain sample extracts free of interfering compounds. Combining sulphuric acid digestion and SPE with Florisil led to the highest efficiency in the elimination of interferences from the extracts. The sample procedure developed, together with the application of GC–(NCI)MS for measurement, led to the satisfactory determination of PBDEs at μg kg −1 levels in complex aquaculture matrices with high lipid content. The use of a short and thin film-thickness fused-silica capillary column allowed to determine the problematic BDE 209 with satisfactory results. Three m/z ions were acquired for each analyte, which ensured a reliable identification of compounds detected in samples.
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A reliable analytical approach based on gas chromatography coupled to triple quadrupole and time-of-flight mass analyzers for the determination and confirmation of polycyclic aromatic hydrocarbons in complex matrices from aquaculture activities.
Rapid communications in mass spectrometry : RCM, 2009Co-Authors: Jaime Nácher-mestre, Roque Serrano, Félix Hernández, Laura Benedito-palos, Tania Portolés-nicolau, Jaume Pérez-sánchezAbstract:The potential of gas chromatography coupled to tandem mass spectrometry (GC/MS/MS) with a triple quadrupole analyzer (QqQ) has been investigated for the quantification and reliable identification of sixteen polycyclic aromatic hydrocarbons (PAHs) from the EPA priority list in animal and vegetable samples from aquaculture activities, whose fat content ranged from 5 to 100%. Matrices analyzed included Fish Fillet, Fish feed, Fish oil and linseed oil. Combining optimized saponification and solid-phase extraction led to high efficiency in the elimination of interfering compounds, mainly fat, from the extracts. The developed procedure minimized the presence of these interfering compounds in the extracts and provided satisfactory recoveries of PAHs. The excellent sensitivity and selectivity of GC/(QqQ)MS/MS in selected reaction monitoring (SRM) allowed to reach limits of detection at pg/g levels. Two SRM transitions were acquired for each analyte to ensure reliable identification of compounds detected in samples. Confirmation of positive findings was performed by GC coupled to high-resolution time-of-flight mass spectrometry (GC/TOFMS). The accurate mass information provided by GC/TOFMS in full acquisition mode together with its high mass resolution makes it a powerful analytical tool for the unequivocal confirmation of PAHs in the matrices tested. The method developed was applied to the analysis of real-world samples of each matrix studied with the result of detecting and confirming the majority of analytes at the microg/kg level by both QqQ and TOF mass spectrometers.
Matthew J. Picklo - One of the best experts on this subject based on the ideXlab platform.
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deposition and mobilization of lipids varies across the rainbow trout Fillet during feed deprivation and transition from plant to Fish oil based diets
Aquaculture, 2018Co-Authors: Beth M Cleveland, Susan K Raatz, Benjamin K Hanson, Angelie Wickramaratne, Matthew J. PickloAbstract:Abstract Identifying aquaculture feeding strategies that reduce the consumption of Fish oil without sacrificing the cardioprotective lipid profile of the salmonid Fillet will improve aquafeed economics and sustainability. Transitioning Fish from a plant oil-based diet to a finishing diet rich in Fish oil and long chain n-3 fatty acids (LCn3) for several weeks prior to harvest is effective at boosting the fatty acid profile of the whole salmonid Fillet. This study determined whether the response to short-term feed deprivation and a finishing diet varies across different regions of the triploid rainbow trout Fillet. Fish were placed on one of three feeding treatments: 1) FO: a Fish oil (FO) diet for the entirety of the 20-week study, 2) VO/FO: a vegetable oil (VO) diet between weeks 1–12 then the FO diet for the final eight weeks, or 3) VO/fd/FO: the VO diet between weeks 1–12 followed by a two week period of feed deprivation before transitioning to the FO diet for the final six weeks. Fillets were divided horizontally into three sections (ventral, central, and dorsal) and the fatty acid profile of each was determined. There were unique responses to feed deprivation across Fillet regions; the central region exhibited a loss of fatty acids, the dorsal region gained fatty acids, but there was no net gain or loss of fatty acids in the ventral region. The ventral and dorsal regions responded similarly to a high-FO finishing diet, increasing concentrations of fatty acids and LCn3, although not to levels observed in the FO treatment group. In contrast, the fatty acid profile in the central region remained largely unaffected by the finishing diet, with the exception of LCn3 in the VO/FO group that increased to levels comparable to the FO-treatment group. Expression of genes related to muscle atrophy (fbxo32) and LCn3 metabolism (fads5) also varied across different Fillet regions and in response to dietary treatments. This study provides evidence for spatially distinct regulation of muscle growth and lipid metabolism that support region-specific physiological and metabolic responses to feeding strategies.
Lima, Guilherme Antonio Mercado Ribeiro - One of the best experts on this subject based on the ideXlab platform.
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Parâmetros de textura e estudo da mobilidade da água por ressonância magnética nuclear no peixe pintado (Pseudoplatystoma corruscans) liofilizado
'Universidade de Sao Paulo Agencia USP de Gestao da Informacao Academica (AGUIA)', 2020Co-Authors: Lima, Guilherme Antonio Mercado RibeiroAbstract:O Pintado (Pseudoplatystoma corruscans), um peixe de água doce encontrado no Pantanal do Mato Grosso, Brasil, é um peixe de grande tamanho, alta precocidade e excelente prolificidade. É visto como uma ótima opção para a piscicultura e a sua conservação, pela redução do teor de umidade, é muito importante, pois inibe alterações químicas ou biológicas indesejáveis entre a pesca e o consumidor final. A Liofilização é o único método prático para a produção de filés de peixes secos de alta qualidade, com mínimas alterações físicas ou químicas. Para a realização adequada de uma liofilização é necessária a aquisição de parâmetros físico-químicos que orientem na condução do processo de forma mais eficiente. O presente trabalho avaliou a mobilidade da água e a transição vítrea por ressonância magnética nuclear (RMN) e estudou as isotermas de sorção de umidade para encontrar os parâmetros que otimizam a liofilização. O estudo permitiu a obtenção da umidade de máxima estabilidade do produto final para as temperaturas de 10, 25, 35 e 40°C, o calor isotérico de sorção de água do peixe Pintado em diferentes teores de umidade, e a temperatura máxima da fase primária da liofilização. A liofilização, utilizando os parâmetros obtidos, foi avaliada através da análise do perfil de textura (TPA) e do perfil de ácidos graxos. Os modelos matemáticos de GAB e BET foram aplicados para ajustar as isotermas de sorção de água, possibilitando a obtenção dos valores de umidade na monocamada em todas as temperaturas estudadas. Os tempos de relaxação spin-spin (T2) da água nos filés do peixe Pintado, foram estudados pela utilização do método CPMG por ressonância magnética nuclear de baixa resolução (23 MHz) 1H. Os experimentos avaliaram a variação da temperatura e da umidade utilizando o software MARAN WinDXP. Os resultados obtidos apresentaram espectros de T2 que permitiram visualizar as diferentes mobilidades da água no peixe Pintado, com tempos de relaxação (T2) distintos.Pintado (Pseudoplatystoma corruscans) is a freshwater Fish from the swamp of Mato Grosso, Brazil. Its large size, precocity, and high prolificity make it adequate for the practice of Fish culture. Freeze-drying is the only practical method for the production of high quality dehydrated Fillet Fish with minimal physical and chemical changes. In foods, water is the most important component in the system, because it influences so many process variables, product characteristics, and stability attributes. The molecular mobility is considered as the key to product stability. Availability of water indicates how freely water molecules can participate in reactions. We studied the theoretical and practical applications of the thermodynamics of water sorption to a freeze-dried Pintado Fish, through the isotherms of sorption of water. It were analyzed the texture profile parameters of hardness, cohesiveness, adhesiveness, and chewiness. The mathematical model of GAB and BET was fitted to the data of the sorption isotherms. The temperature had influence on the isotherm, when the temperature increased the amount of water sorbed decrease, resulting in an influence on the distribution of isotherm. Recently, NMR measurements have been considered a faster and more reliable measure of the availability of water in complex systems. We studied the relaxation time (T2) from CPMG experiments in pulsed 1H NMR of the edible portion (Fillets) in the temperatures of -70 up to 60°C and in the freeze-dried Fillets, reconstituted to moisture content of 1 % up to 32%, at 10, 25 and 40ºC. Analysis of the data obtained from CPMG experiments using the MARAN WinDXP software resulted in spectra of T2. As a result of the experiments one to three peaks of water appear on each spectrum. Each of which had a distinct relaxation time (T2) showing a distinct molecular mobility. It was obtained profiles of water fractions with distinct mobility as affected by environments conditions of temperature, moisture and water activity
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Relações entre migração e redistribuição de umidade, sobre a qualidade e estabilidade do peixe pintado (Pseudoplatystoma corruscans) liofilizado
'Universidade de Sao Paulo Agencia USP de Gestao da Informacao Academica (AGUIA)', 2020Co-Authors: Lima, Guilherme Antonio Mercado RibeiroAbstract:A liofilização tem como objetivo estabilizar alimentos, por meio das múltiplas operações, as quais o material é submetido durante o processamento: congelamento, sublimação, secagem a vácuo, além do armazenamento do material seco sob condições controladas. Além disso, obter produtos da mais alta qualidade, com reconstituição instantânea e que ainda possuam longo tempo de vida de prateleira. O Pintado (Pseudoplatystoma corruscans) é um peixe de água doce encontrado no Pantanal do Mato Grosso, Brasil. Seu tamanho, precocidade e alta prolificidade fazem do mesmo uma ótima opção para a piscicultura. A Liofilização é o único método prático para a produção de filés de peixes secos de alta qualidade, com mínimas alterações físicas ou químicas. Em alimentos, a água é o componente mais importante do sistema, pois influencia muitas variáveis do processamento, características do produto e atributos de estabilidade. A mobilidade molecular é considerada a chave para a estabilidade do produto. A disponibilidade da água indica quão livremente as moléculas de água podem participar das reações. O objetivo deste projeto foi estudar as relações entre migração e redistribuição de umidade, sobre a qualidade e estabilidade dos liofilizados. Foi determinada a influência das variáveis de processo (pressão na câmara de liofilização e temperatura das placas de aquecimento que variaram de 0 a 1200mT e de -10 a 50°C, respectivamente) sobre a qualidade do produto final e tempo de liofilização. Os critérios definidos para avaliar a qualidade do produto foram cor, taxa de reidratação, mobilidade molecular e textura. A otimização das condições de liofilização dos filés de pintado foi determinada pelo uso do método da superfície de resposta. A técnica de ressonância magnética nuclear de baixa resolução CPMG (T2), foi empregada para estudar as relações entre migração e redistribuição de umidade, sobre a qualidade e estabilidade dos liofilizados.Freeze-drying consists in a multistage operation that stabilizes foods through the four main operations: freezing, sublimation or primary drying, desorption stage or secondary drying and storage of the dried material under controlled conditions. Moreover, freeze-drying allows obtaining products of superior quality, which are easily reconstituted and have long shelf-life. This long shelf life eases manufacture, distribution, and storage. Pintado (Pseudoplatystoma corruscans) is a freshwater Fish from the swamp of Mato Grosso, Brazil. Its large size precocíty and high prolificacy make it adequate for the practice of Fish culture. Freeze-drying is the only practical method for the production of high quality dehydrated Fillet Fish with minimal physical and chemical changes. In foods, water is the most important component in the system, because it influences so many process variables, product characteristics, and stability attributes. The molecular mobility is considered as the key to product stability. The objective of this study was to determine the influence of process variables and freeze-drying time on the quality of the products. The criteria defined to evaluate the quality of the product were: calor, hydration rate, moisture migration and texture. The freeze-drying optimization was performed using the surface response method. In this study a pulse nuclear magnetic resonance 1H NMR technique was used to determine the percentage of the signal on relaxation times (T21, T22 and T23) from CPMG experiments on Fillets of freeze dried samples of Pintado (Pseudoplatystoma corruscans) at 5 to 45°C and in the freeze-dried Fillets was rehydrated in a controlled manner in environments chambers (100% relative humidity) at 25°C. Analysis of the data obtained from CPMG experiments using the MARAN WinDXP software resulted in a spectra of T2. It was obtained profiles of water fractions with distinct mobility. These profiles were affected by environments conditions as temperature, moisture and water activity. The resonance magnetic technique using CPMG (T2) method was used to study the water relations in Pintado Fish: migration, redistribution and their influences on quality and stability of the freeze dried products
Jaime Nácher-mestre - One of the best experts on this subject based on the ideXlab platform.
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Gas chromatography-mass spectrometric determination of polybrominated diphenyl ethers in complex fatty matrices from aquaculture activities.
Analytica chimica acta, 2010Co-Authors: Jaime Nácher-mestre, Roque Serrano, Félix Hernández, Laura Benedito-palos, Jaume Pérez-sánchezAbstract:Abstract Gas chromatography coupled to mass spectrometry in negative chemical ionization mode (GC–(NCI)MS) has been applied to the quantification and reliable identification of polybrominated diphenyl ethers (PBDEs) in animal and vegetable samples from aquaculture activities. Matrices analyzed included Fish Fillet, Fish feed, Fish oil and linseed oil, their fat content ranged from 5% to 100%. Solid-phase extraction (SPE) (using Florisil and silica cartridges) and normal-phase high performance liquid chromatography were tested for an efficient clean-up in order to obtain sample extracts free of interfering compounds. Combining sulphuric acid digestion and SPE with Florisil led to the highest efficiency in the elimination of interferences from the extracts. The sample procedure developed, together with the application of GC–(NCI)MS for measurement, led to the satisfactory determination of PBDEs at μg kg −1 levels in complex aquaculture matrices with high lipid content. The use of a short and thin film-thickness fused-silica capillary column allowed to determine the problematic BDE 209 with satisfactory results. Three m/z ions were acquired for each analyte, which ensured a reliable identification of compounds detected in samples.
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A reliable analytical approach based on gas chromatography coupled to triple quadrupole and time-of-flight mass analyzers for the determination and confirmation of polycyclic aromatic hydrocarbons in complex matrices from aquaculture activities.
Rapid communications in mass spectrometry : RCM, 2009Co-Authors: Jaime Nácher-mestre, Roque Serrano, Félix Hernández, Laura Benedito-palos, Tania Portolés-nicolau, Jaume Pérez-sánchezAbstract:The potential of gas chromatography coupled to tandem mass spectrometry (GC/MS/MS) with a triple quadrupole analyzer (QqQ) has been investigated for the quantification and reliable identification of sixteen polycyclic aromatic hydrocarbons (PAHs) from the EPA priority list in animal and vegetable samples from aquaculture activities, whose fat content ranged from 5 to 100%. Matrices analyzed included Fish Fillet, Fish feed, Fish oil and linseed oil. Combining optimized saponification and solid-phase extraction led to high efficiency in the elimination of interfering compounds, mainly fat, from the extracts. The developed procedure minimized the presence of these interfering compounds in the extracts and provided satisfactory recoveries of PAHs. The excellent sensitivity and selectivity of GC/(QqQ)MS/MS in selected reaction monitoring (SRM) allowed to reach limits of detection at pg/g levels. Two SRM transitions were acquired for each analyte to ensure reliable identification of compounds detected in samples. Confirmation of positive findings was performed by GC coupled to high-resolution time-of-flight mass spectrometry (GC/TOFMS). The accurate mass information provided by GC/TOFMS in full acquisition mode together with its high mass resolution makes it a powerful analytical tool for the unequivocal confirmation of PAHs in the matrices tested. The method developed was applied to the analysis of real-world samples of each matrix studied with the result of detecting and confirming the majority of analytes at the microg/kg level by both QqQ and TOF mass spectrometers.
Beth M Cleveland - One of the best experts on this subject based on the ideXlab platform.
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deposition and mobilization of lipids varies across the rainbow trout Fillet during feed deprivation and transition from plant to Fish oil based diets
Aquaculture, 2018Co-Authors: Beth M Cleveland, Susan K Raatz, Benjamin K Hanson, Angelie Wickramaratne, Matthew J. PickloAbstract:Abstract Identifying aquaculture feeding strategies that reduce the consumption of Fish oil without sacrificing the cardioprotective lipid profile of the salmonid Fillet will improve aquafeed economics and sustainability. Transitioning Fish from a plant oil-based diet to a finishing diet rich in Fish oil and long chain n-3 fatty acids (LCn3) for several weeks prior to harvest is effective at boosting the fatty acid profile of the whole salmonid Fillet. This study determined whether the response to short-term feed deprivation and a finishing diet varies across different regions of the triploid rainbow trout Fillet. Fish were placed on one of three feeding treatments: 1) FO: a Fish oil (FO) diet for the entirety of the 20-week study, 2) VO/FO: a vegetable oil (VO) diet between weeks 1–12 then the FO diet for the final eight weeks, or 3) VO/fd/FO: the VO diet between weeks 1–12 followed by a two week period of feed deprivation before transitioning to the FO diet for the final six weeks. Fillets were divided horizontally into three sections (ventral, central, and dorsal) and the fatty acid profile of each was determined. There were unique responses to feed deprivation across Fillet regions; the central region exhibited a loss of fatty acids, the dorsal region gained fatty acids, but there was no net gain or loss of fatty acids in the ventral region. The ventral and dorsal regions responded similarly to a high-FO finishing diet, increasing concentrations of fatty acids and LCn3, although not to levels observed in the FO treatment group. In contrast, the fatty acid profile in the central region remained largely unaffected by the finishing diet, with the exception of LCn3 in the VO/FO group that increased to levels comparable to the FO-treatment group. Expression of genes related to muscle atrophy (fbxo32) and LCn3 metabolism (fads5) also varied across different Fillet regions and in response to dietary treatments. This study provides evidence for spatially distinct regulation of muscle growth and lipid metabolism that support region-specific physiological and metabolic responses to feeding strategies.