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Determinação expedita de aminas biogénicas em cogumelos por TLC

Coelho, Susete
Fonte: Instituto Politécnico de Bragança, Escola Superior Agrária Publicador: Instituto Politécnico de Bragança, Escola Superior Agrária
Tipo: Dissertação de Mestrado
POR
Relevância na Pesquisa
47.26%
A presença de aminas biogénicas nos alimentos é um ponto crítico da segurança alimentar pela sua ligação a casos de intoxicações alimentares, sendo por isso importante testar e otimizar novas metodologias analíticas para a deteção e quantificação destes compostos. Neste trabalho, pretendeu-se otimizar uma metodologia baseada na técnica de cromatografia em camada fina para analisar 7 aminas biogénicas: cadaverina, espermina, espermidina, putrescina, tiramina, 2-feniletilamina e histamina. Numa primeira fase, testou-se a eficácia de separação de três eluentes distintos, tendo-se selecionando o eluente clorofórmio: éter diétilico: trietilamina (40:10:10) porque permitiu melhor resolução entre os picos das aminas biogénicas. Posteriormente, avaliou-se o desempenho da metodologia analítica relativamente à calibração de cada amina biogénica para a análise quantitativa. Os coeficientes de correlação (R) obtidos para a maioria das aminas biogénicas foi superior a 0,99, exceto na calibração da 2-fenileilamina cujo R=0,977. Os limites de deteção situaram-se entre 2,6 mg/L (tiramina) e 5,8 mg/L (2-feniletilamina), enquanto os limites de quantificação se situam entre 7,9 mg/L (tiramina) e 17,6mg/L (2-feniletilamina). Finalmente...

Novos dispositivos de microextração e pré-concentração para eletroforese capilar utilizando membranas microporosas ou processos eletroquímicos e sua potencialidade na análise de aminas e metais; New devices to extraction and preconcentration with microporous membranes and electrochemical procedures prior to capillary electrophoresis: some applications to amines and metals analysis

Antunes Junior, Osmar
Fonte: Biblioteca Digitais de Teses e Dissertações da USP Publicador: Biblioteca Digitais de Teses e Dissertações da USP
Tipo: Tese de Doutorado Formato: application/pdf
Publicado em 13/10/2008 PT
Relevância na Pesquisa
56.97%
A eletroforese capilar (CE) é uma técnica de separação eficiente, que tem merecido grande atenção nas últimas duas décadas, e que oferece soluções analíticas alternativas ou complementares à cromatografia líquida num número crescente campos de aplicação, incluindo análises de fármacos, compostos biológicos e biogênicos, dentre outros. Entre as vantagens comparativas da técnica figuram separações mais rápidas com pequeno dispêndio de amostras, solução tampão (e solvente orgânico, se usado), baixo custo de operação e manutenção. Todavia, a exigüidade de amostra no capilar tem como reflexo, via de regra, limites de detecção menos favoráveis que os da HPLC, uma limitação significativa na análise de traços, suplantável por técnicas e procedimentos de extração/acumulação prévia dos analitos. Nesta tese concebeu-se e implementou-se a combinação inédita entre a CE e a préconcentração eletroquímica de metais. Novos dispositivos para extração líquido/gás/líquido mediada por membranas microporosas também foram propostos e aplicados à analise de aminas voláteis, sempre utilizando detector de condutância medida sem contato direto com a solução (C4D, contactless capacitively coupled conductivity detection). Primeiramente...

Perfil antipsicótico de alstonina : ação em modelos de sintomas negativos, alterações em aminas biogênicas e efeitos adversos em camundongos; Antipsychotic profile of alstonine : action in animal models of negative symptoms, alterations in biogenic amines and side effects in mice.

Linck, Viviane de Moura
Fonte: Universidade Federal do Rio Grande do Sul Publicador: Universidade Federal do Rio Grande do Sul
Tipo: Dissertação Formato: application/pdf
POR
Relevância na Pesquisa
66.83%
A esquizofrenia é um transtorno psiquiátrico grave, caracterizado por distúrbios do pensamento, prejuízo da lógica, alterações cognitivas e emocionais, e/ou isolamento social. Apesar da introdução de novos antipsicóticos, um grupo considerável de pacientes ainda é refratário aos tratamentos disponíveis. Além disso, a alta incidência de efeitos adversos leva à baixa adesão ao tratamento em esquizofrênicos. O desenvolvimento de tratamentos mais eficazes e com menor incidência de efeitos adversos, que aumentem a adesão ao tratamento e melhorem a qualidade de vida destes pacientes, é assim altamente desejável. Em uma expedição etnofarmacológica entre os Igbo na Nigéria identificou-se uma preparação a base de plantas usada no tratamento de pacientes com distúrbios mentais. O alcalóide indólico alstonina é o componente majoritário desta preparação, e possui um claro perfil comportamental de antipsicótico atípico em modelos animais de sintomas positivos, com aparentes vantagens em relação à clozapina. Este trabalho teve o objetivo principal de dar continuidade à caracterização de alstonina como fármaco antipsicótico. Demonstramos que este alcalóide aumenta a interação social e previne o déficit de interação social induzido por MK801 em camundongos...

Aminas biogenicas, aminas volateis, triptofano livre e ureia como indices quimicos de qualidade e frescor do pescado.; Biogenic amines, volatile amines, free tryptophan and urea as chemical indices for quality and freshness evaluation of fish and sellfish.

Judite Lapa Guimarães
Fonte: Biblioteca Digital da Unicamp Publicador: Biblioteca Digital da Unicamp
Tipo: Tese de Doutorado Formato: application/pdf
Publicado em 12/08/2005 PT
Relevância na Pesquisa
67.26%
Em função da alta perecibilidade do pescado, a avaliação do frescor e qualidade deste alimento deve ser precisa e baseada em métodos consolidados. Bases nitrogenadas voláteis (BNV), trimetilamina (TMA), aminas biogênicas, nucleotídeos, uréia e triptofano livre têm sido propostos como índices de frescor para pescado e podem ser efetivos ou não dependendo da espécie de pescado, microbiota contaminante e condições de armazenamento. A quantificação dos teores de aminas biogênicas é também importante devido ao seu potencial tóxico. Os objetivos deste estudo foram avaliar a utilidade das aminas biogênicas, BNV, TMA, triptofano livre e uréia como índices de qualidade e frescor em peixes e moluscos cefalópodes, desenvolver e avaliar sistemas de solventes para separação de aminas biogênicas por cromatografia de camada delgada e avaliar o efeito do tempo e temperatura de derivatização sobre a conversão das aminas biogênicas em seus derivados dansilados. Derivados dansilados de agmatina (AGM), putrescina (PUT), triptamina (TRY), cadaverina (CAD), histamina (HIS), espermidina (SPD), espermina (SPM), tiramina (TYR) e feniletilamina (PHE) foram separados utilizando-se o sistema de solventes clorofórmio: éter dietílico: trietilamina (6:4:1 - v/v) seguido de clorofórmio: trietilamina (6:1 - v/v). A melhor condição para derivatização das aminas biogênicas com cloreto de dansila foi 1h a 40oC. AGM permaneceu no local de aplicação (RF=0...

Free amino acids and biogenic amines in wines and musts from

Herbert, Paulo; Cabrita, Maria João; Ratola, Nuno; Laureano, Olga; Alves, Arminda
Fonte: Universidade de Évora Publicador: Universidade de Évora
Tipo: Artigo de Revista Científica Formato: 306271 bytes; application/pdf
ENG
Relevância na Pesquisa
56.78%
Characterization of musts and wines from different Alentejo sub-regions, varieties and vintages was made in terms of amino acid and amine contents, by HPLC with fluorescence detection of OPA/FMOC derivatives. The evolution of volatile and biogenic amines was also studied throughout 10 microvinifications. No significant increase in the levels of total volatile amines was observed during alcoholic or spontaneous malolactic fermentation. While higher histamine levels were only found during the storage period, an increase in the concentration of tyramine was confirmed in red wines immediately after malolactic fermentation, which seems to be also the main origin of putrescine. It was noticed that grape variety, region of production, and vintage can influence free amino acid and amine contents of musts and wines, although alcoholic and malolactic fermentations can override that effect.

Relationship Between Biogenic Amines and Free Amino Acid Contents of Winesand Musts from Alentejo (Portugal)

Herbert, Paulo; Cabrita, Maria Joao; Ratola, Nuno; Laureano, Olga; Alves, Arminda
Fonte: Taylor & Francis Publicador: Taylor & Francis
Tipo: Artigo de Revista Científica
ENG
Relevância na Pesquisa
57.01%
The concentration of biogenic amines and free amino acids was studied in 102 Portuguese wines and 18 musts from Alentejo demarcated (D.O.C.) regions. Most wines were commercial, except for 38 monovarietals obtained by micro vinification. Musts from the varieties used to produce the latter wines were also studied. Both biogenic amines and free amino acids were analyzed by HPLC using fluorescence detection for their o-phthalaldehyde/fluorenylmethyl chloroformate (OPA/FMOC) derivatives. The most significant amines (average 10.8 mg/L for histamine+tyramine in red, and 7.4 mg/L for white wines) were found to be present at low levels and, although no important relationship between each individual biogenic amine could be obtained, the total amine content depends significantly on the assimilable amino acid content in wine.

Biogenic amines in wine: gene transcription as a tool for selection of Oenococcus oeni starter strains

Marques, Ana Paula Gomes
Fonte: Universidade Nova de Lisboa. Instituto de Tecnologia Química e Biológica Publicador: Universidade Nova de Lisboa. Instituto de Tecnologia Química e Biológica
Tipo: Tese de Doutorado
Publicado em /01/2012 ENG
Relevância na Pesquisa
47.13%
Dissertation presented to obtain the Ph.D degree in Biology; Wine is a complex environment where the microbial flora can have both a positive (e.g. malolactic fermentation) and a negative (e.g. production of biogenic amines) impact on the quality of wine. Biogenic amines are nitrogenous compounds of low molecular weight that can be found in fermented food and beverages, including wine. Biogenic amines are formed primarily by decarboxylation of the corresponding amino acids by microorganisms through substrate-specific decarboxylases. Some authors consider the presence of biogenic amines to be a fundamental parameter for detriment of alcoholic beverages. These compounds can have adverse health effects on sensitive individuals at high concentrations. The role of microorganisms in wine involves two important fermentation processes, the alcoholic fermentation conducted by yeasts and the malolactic fermentation conducted by lactic acid bacteria. The malolactic fermentation refers to the conversion of L-malic acid into L-lactic acid and CO2, catalysed by the malolactic enzyme. This mechanism contributes for deacidification, bacterial stability and flavour changes in wine. Oenococcus oeni is the leading lactic acid bacteria responsible for malolactic fermentation...

Detection of biogenic amines in urine and plasma by liquid chromatography coupled to electrochemical detection HPLC-ED using microextraction in packed syringe MEPS

Oppolzer, David Jerónimo
Fonte: Universidade da Beira Interior Publicador: Universidade da Beira Interior
Tipo: Dissertação de Mestrado
Publicado em //2012 ENG
Relevância na Pesquisa
67.13%
Biogenic amines are neurotransmitters involved in several physiological processes. Changes and disturbs in their function are associated to several neurological disorders or diseases, as well as consumption of psychotherapeutic or psychotropic drugs. The detection of these compounds in biological fluids is therefore of clinical and neurochemical interest. The goal of this work was to develop and validate and analytical method for the detection and quantification of the biogenic amines serotonin (5-HT), dopamine (DA) and norepinephrine (NE), using microextraction in packed syringe (MEPS) and liquid chromatography coupled to electrochemical detection (HPLC-ED) in both urine and plasma samples. The internal standard used was 3,4-dihydroxybenzylamine (DHBA). The MEPS extraction procedure was optimized using the design of experiments (DOE) tool, and the final conditions of 8 strokes, no washing, and two elutions of 100 FL methanol were chosen. The method was fully validated according to internationally accepted guidelines from the Food and Drug Administration. Linearity was established between 50-1000 ng/mL for 5-HT and between 5-1000 ng/mL for DA and NE, with determination coefficients (R2) higher than 0.99 for all compounds. The limits of detection and quantification were respectively 20 and 50 ng/mL for 5-HT...

The influences of fish infusion broth on the biogenic amines formation by lactic acid bacteria

Küley,Esmeray; Özogul,Fatih; Balikçi,Esra; Durmus,Mustafa; Ayas,Deniz
Fonte: Sociedade Brasileira de Microbiologia Publicador: Sociedade Brasileira de Microbiologia
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/01/2013 EN
Relevância na Pesquisa
66.89%
The influences of fish infusion decarboxylase broth (IDB) on biogenic amines (BA) formation by lactic acid bacteria (LAB) were investigated. BA productions by single LAB strains were tested in five different fish (anchovy, mackerel, white shark, sardine and gilthead seabream) IDB. The result of the study showed that significant differences in ammonia (AMN) and BA production were observed among the LAB strains in fish IDB (p < 0.05). The highest AMN and TMA production by LAB strains were observed for white shark IDB. The all tested bacteria had decarboxylation activity in fish IDB. The uppermost accumulated amines by LAB strains were tyramine (TYM), dopamine, serotonin and spermidine. The maximum histamine production was observed in sardine (101.69 mg/L) and mackerel (100.84 mg/L) IDB by Leuconostoc mesenteroides subsp. cremoris and Pediococcus acidophilus, respectively. Lactobacillus delbrueckii subsp. lactis and Pediococcus acidophilus had a high TYM producing capability (2943 mg/L and 1157 mg/L) in sardine IDB.

Multiplexe Immunoassays zur Quantifizierung von biogenen Aminen; Multiplex immunoassays for the quantification of biogenic amines

Baur, Nadja
Fonte: Universidade de Tubinga Publicador: Universidade de Tubinga
Tipo: Dissertação
DE
Relevância na Pesquisa
66.83%
Biogenic amines, among them catecholamines and serotonin, play a pivotal role in a multitude of physiological processes in the human body like neurotransmission, the regulation of the cardiovascular system, and the regulation of many metabolic processes. As a result of their manifold functions, catecholamines and their inactive metabolites, the metanephrines, as well as serotonin play also an important role in different diseases as changes in their concentrations in human body fluids like plasma and urine can provide important information about the underlying disease. Among these diseases, tumor diseases like the pheochromocytoma, neurodegenerative diseases as well as degenerative heart diseases are of great importance. In an aging society, diseases like Alzheimer’s disease, Parkinson’s disease or tumor diseases occur more and more often and there is an increasing need for the fast, safe, efficient and precise diagnosis of these diseases. Determination of plasma and urinary catecholamines and metanephrines is generally considered as a principal test for the clinical chemical diagnosis of these diseases. Therefore, there is great interest to measure these analytes in an efficient and cost-effective multiplex format. Multiplex immunoassays allow the determination of multiple parameters in a single sample and only low sample volumes are needed. Furthermore...

Detection of biogenic amines in urine and plasma by liquid chromatography coupled to electrochemical detection HPLC-ED using microextraction in packed syringe MEPS

Oppolzer, David Jerónimo
Fonte: Universidade da Beira Interior Publicador: Universidade da Beira Interior
Tipo: Dissertação de Mestrado
Publicado em //2012 ENG
Relevância na Pesquisa
67.13%
Biogenic amines are neurotransmitters involved in several physiological processes. Changes and disturbs in their function are associated to several neurological disorders or diseases, as well as consumption of psychotherapeutic or psychotropic drugs. The detection of these compounds in biological fluids is therefore of clinical and neurochemical interest. The goal of this work was to develop and validate and analytical method for the detection and quantification of the biogenic amines serotonin (5-HT), dopamine (DA) and norepinephrine (NE), using microextraction in packed syringe (MEPS) and liquid chromatography coupled to electrochemical detection (HPLC-ED) in both urine and plasma samples. The internal standard used was 3,4-dihydroxybenzylamine (DHBA). The MEPS extraction procedure was optimized using the design of experiments (DOE) tool, and the final conditions of 8 strokes, no washing, and two elutions of 100 FL methanol were chosen. The method was fully validated according to internationally accepted guidelines from the Food and Drug Administration. Linearity was established between 50-1000 ng/mL for 5-HT and between 5-1000 ng/mL for DA and NE, with determination coefficients (R2) higher than 0.99 for all compounds. The limits of detection and quantification were respectively 20 and 50 ng/mL for 5-HT...

Validation of an HPLC Analytical Method for Determination of Biogenic Amines in Agricultural Products and Monitoring of Biogenic Amines in Korean Fermented Agricultural Products

Yoon, Hyeock; Park, Jung Hyuck; Choi, Ari; Hwang, Han-Joon; Mah, Jae-Hyung
Fonte: The Korean Society Of Toxicology Publicador: The Korean Society Of Toxicology
Tipo: Artigo de Revista Científica
Publicado em /09/2015 EN
Relevância na Pesquisa
47.21%
An HPLC analytical method was validated for the quantitative determination of biogenic amines in agricultural products. Four agricultural foods, including apple juice, Juk, corn oil and peanut butter, were selected as food matrices based on their water and fat contents (i.e., non-fatty liquid, non-fatty solid, fatty liquid and fatty solid, respectively). The precision, accuracy, recovery, limit of detection (LOD) and quantification (LOQ) were determined to test the validity of an HPLC procedure for the determination of biogenic amines, including tryptamine, β-phenylethylamine, putrescine, cadaverine, histamine, tyramine, spermidine and spermine, in each matrix. The LODs and LOQs for the biogenic amines were within the range of 0.01~0.10 mg/kg and 0.02~0.31 mg/kg, respectively. The relative standard deviation (RSD) of intraday for biogenic amine concentrations ranged from 1.86 to 5.95%, whereas the RSD of interday ranged from 2.08 to 5.96%. Of the matrices spiked with biogenic amines, corn oil with tyramine and Juk with putrescine exhibited the least accuracy of 84.85% and recovery rate of 89.63%, respectively, at the lowest concentration (10 mg/kg). Therefore, the validation results fulfilled AOAC criteria and recommendations. Subsequently...

Ion-trap versus time-of-flight mass spectrometry coupled to capillary electrophoresis to analyze biogenic amines in wine

Simó, Carolina; Moreno-Arribas, M. Victoria; Cifuentes, Alejandro
Fonte: Elsevier Publicador: Elsevier
Tipo: Artículo Formato: 24064 bytes; application/msword
ENG
Relevância na Pesquisa
57.26%
In this work, two different capillary electrophoresis-mass spectrometry (CE-MS) methods, namely, capillary electrophoresis-ion-trap mass spectrometry (CE-IT-MS) and capillary electrophoresis-time-of-flight mass spectrometry (CE-TOF-MS), applied to analyze biogenic amines in wine samples are investigated. A group of five amines was selected as case study (namely, putrescine, cadaverine, histamine, phenylethylamine and tyramine) since they are the most frequently biogenic amines found in wines. The possibilities of both instruments in terms of sensitivity, selectivity and quantitation. during the determination of the mentioned biogenic amines in wine samples was studied and their results corroborated by HPLC. After optimization of the analytical conditions, CE-IT-MS and CE-TOF-MS allowed the identification of biogenic amines in wines without any previous treatment except diluting 1:1 with water and filtering. Biogenic amines were determined in three red wines and one white wine showing, as expected, a higher concentration in red wines. Moreover, CE-IT-MS and CE-TOF-MIS were compared regarding their capacity to detect other biogenic amines different to the selected ones in wine samples, showing CE-TOF-MS a much better capability (i.e....

Occurrence of lactic acid bacteria and biogenic amines in biologically aged wines

Moreno-Arribas, M. Victoria; Polo, María Carmen
Fonte: Elsevier Publicador: Elsevier
Tipo: Artículo Formato: 24064 bytes; application/msword
ENG
Relevância na Pesquisa
66.95%
Biologically aged sherry-type wines are elaborated by the so-called 'criadera and solera' system, which essentially involves development of the yeast on the wine surface forming a film velum for several years. Lactic acid bacteria can also develop and contribute to sherry-type wine quality, although their presence and role in this enological process have received very little attention. In this study, lactic acid bacteria microbiota and the presence of biogenic amines were investigated throughout the manufacture and biological aging of 36 samples of sherry wines. Malolactic fermentation was found to mainly take place during the first stage of biological ageing. The incidence and populations of lactic acid bacteria in sherry wines were low. The diversity of bacterial species isolated from the wines was greater than previously reported and included species of Lactobacillus, with prevailing Lactobacillus hilgardii, Lactobacillus plantarum and Lactobacillus zeae and Leuconostoc mesenteroides. The biogenic amine-producing capacity of the isolates was also determined. Five strains were putrescine producers, while another strain was shown to produce tyramine and phenylethylamine, simultaneously. L zeae was one of the predominant species in wines during the biological aging and seemed to be one of the main putrescine producers. The biogenic amine composition of the wines investigated was similar to that reported for other types of wines. Putrescine was the major amine...

HPLC quantification of biogenic amines in cheeses: correlation with PCR-detection of tyramine-producing microorganisms

Fernández García, María; Martínez Linares, Daniel; Río Lagar, Beatriz del; Ladero Losada, Víctor Manuel; Álvarez-González, Miguel Ángel
Fonte: Cambridge University Press Publicador: Cambridge University Press
Tipo: Artículo Formato: 22195 bytes; application/pdf
ENG
Relevância na Pesquisa
66.83%
The consumption of food and beverages containing high amounts of biogenic amines (BA) can have toxicological effects. BA found in foods and beverages are synthesized by the microbial decarboxylation of certain amino acids. This paper reports the concentrations of BAs in a number of commercial cheeses, as determined by HPLC. The cheeses studied were made from raw and pasteurized milk of different origin, and were subjected to different ripening periods. BA concentrations were lower in short ripening period than in long ripening period cheeses, and higher in cheeses made from raw milk than in those made from pasteurized milk. The highest BA concentrations were recorded in blue cheeses made from raw milk. Tyramine was the most commonly recorded and abundant BA. The presence of tyramine-producing bacteria was determined by PCR, and a good correlation obtained between the results of this method and tyramine detection by HPLC. These methods could be used to complement one another in the detection and quantification of tyramine in cheese prevention of tyramine accumulation in cheese.; Peer reviewed

Malolactic bacterial starters in winemaking study of implantation and biogenic amines during malolactic fermentation and storage, and their role in ochratoxin A reduction

Olmos Rizzo, Paola Daniela
Fonte: [Barcelona] : Universitat Autònoma de Barcelona, Publicador: [Barcelona] : Universitat Autònoma de Barcelona,
Tipo: Tesis i dissertacions electròniques; info:eu-repo/semantics/doctoralThesis Formato: application/pdf
Publicado em //2013 ENG; ENG
Relevância na Pesquisa
47.23%
La utilización de bacterias iniciadoras de fermentación maloláctica es de fundamental importancia para los elaboradores de vino comprometidos con la producción de vinos de alta calidad y sin riesgos para la salud, ya que estas bacterias han sido seleccionadas como poco productoras de aminas biógenas. Sin embargo, en ciertas condiciones se obtienen vinos con altos niveles de aminas biógenas, aun cuando estos vinos han sido inoculados con bacterias seleccionadas. En el presente trabajo, con la tipificación de bacterias aisladas de la fermentación maloláctica usando un método basado en RAPD-PCR, se demostró que el estárter maloláctico puede tener diferentes niveles de implantación y que a su vez, esto se correlaciona con la producción de aminas biógenas durante la fermentación maloláctica, lo cual explicaría los altos niveles de aminas obtenidos en vinos inoculados con estárteres malolácticos. Para entender como las diferentes prácticas enológicas afectan la implantación del estárter maloláctico, lisozima, nutrientes, co-inoculación con levaduras, o siembra del estárter por diferentes métodos (inoculación directa o pie de cuba) fueron estudiados respecto al nivel de implantación y producción de aminas biógenas. Luego de la fermentación maloláctica...

Biogenic amines on diet. Analysis by chromatographic techniques

Ortega de Sande, David
Fonte: Universidade Autônoma de Barcelona Publicador: Universidade Autônoma de Barcelona
Tipo: info:eu-repo/semantics/bachelorThesis; Text Formato: application/pdf
Publicado em //2014 ENG
Relevância na Pesquisa
56.71%
Póster; This paper is caring of the harm caused by biogenic amines really being in the diet with a high incidence in minor illnesses. Also will be mentioned in which foods are present, its origin, its detrimental effect and how determined and quantified analytically, giving his interest in f.safety.

Métodos cromatográficos para determinar aminas biogênicas em alimentos de origem animal; Chromatographic methods for biogenic amines determination in foods of animal origin

Lázaro de la Torre, César Aquiles; Conte-Júnior, Carlos Adam
Fonte: Universidade de São Paulo. Faculdade de Medicina Veterinária e Zootecnia Publicador: Universidade de São Paulo. Faculdade de Medicina Veterinária e Zootecnia
Tipo: info:eu-repo/semantics/article; info:eu-repo/semantics/publishedVersion; ; ; ; Formato: application/pdf
Publicado em 09/12/2013 ENG
Relevância na Pesquisa
67.18%
Aminas biogenicas sao formadas como resultado da descarboxilacao de aminoacidos livres especificos. A analise desses metabolitos e de grande importancia na determinacao da qualidade e monitoramento de biogenicas como histamina e tiramina relacionadas com episodios de intoxicacao em humanos. A cromatografia e uma tecnica de separacao química usada para caracterizar aminas biogenicas. Variacoes da tecnica (cromatografia liquida, em camada delgada e gasosa) tem sido amplamente usadas, porem a complexidade da matriz alimentar faz com que sejam realizadas mudancas nos processos de extracao, derivatizacao e deteccao em concordancia com cada grupo de alimento. A cromatografia liquida de alta eficiencia (CLAE) e o metodo mais utilizado na determinacao de aminas biogenicas em alimentos. Contudo, devido a importancia das aminas biogenicas no controle da qualidade e a seguranca do consumidor, os pesquisadores tentam desenvolver novos metodos com o intuito de uma analise mais rapida e precisa para o controle de alimentos no mercado. O objetivo da revisao e apresentar algumas tecnicas cromatograficas aplicadas no monitoramento de aminas biogenicas em produtos de origem animal.; Biogenic amines (BAs) are formed as a result of specific free amino acid decarboxylation. Analysis of these metabolites may be of great importance to determine food quality and for monitoring the levels of biogenic amines such as histamine and tyramine related to intoxication episodes in humans. Chromatography is a chemistry separation technique used to characterize biogenic amines in foods. Variations of this technique (liquid...

Simultaneous analysis of free amino acids and biogenic amines in honey and wine samples using in loop orthophthalaldeyde derivatization procedure

Pereira, V.; Pontes, M.; Câmara, J. S.; Marques, J. C.
Fonte: Elsevier Publicador: Elsevier
Tipo: Artigo de Revista Científica
Publicado em /05/2008 ENG
Relevância na Pesquisa
67.01%
This work presents a RP-HPLC method for the simultaneous quantification of free amino acids and biogenic amines in liquid food matrices and the results of the application to honey and wine samples obtained from different production processes and geographic origins. The developed methodology is based on a pre-column derivatization with o-phthaldialdehyde carried out in the sample injection loop. The compounds were separated in a Nova-Pack RP-C18 column (150 mm × 3.9 mm, 4 μm) at 35 °C. The mobile phase used was a mixture of phase A: 10 mM sodium phosphate buffer (pH 7.3), methanol and tetrahydrofuran (91:8:1); and phase B: methanol and phosphate buffer (80:20), with a flow rate of 1.0 ml/min. Fluorescence detection was used at an excitation wavelength of 335 nm and an emission wavelength of 440 nm. The separation and quantification of 19 amino acids and 6 amines was carried out in a single run as their OPA/MCE derivatives elute within 80 min, ensuring a reproducible quantification. The method showed to be adequate for the purpose, with an average RSD of 2% for the different amino acids; detection limits varying between 0.71 mg/l (Asn) and 8.26 mg/l (Lys) and recovery rates between 63.0% (Cad) and 98.0% (Asp). The amino acids present at the highest concentration in honey and wine samples were phenylalanine and arginine...

Aminas Biogênicas: Um Problema de Saúde Pública; Biogenic Amines: A Public Health Problem

Monique Cardozo; Instituto Militar de Engenharia; Keila S. C. Lima; Instituto Militar de Engenharia; Tanos C. C. Franca; Instituto Militar de Engenharia; Antônio Luiz S. Lima; Instituto Militar de Engenharia
Fonte: Revista Virtual de Química Publicador: Revista Virtual de Química
Tipo: ; Formato: binary/octet-stream
Publicado em 06/05/2013 PT
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Aminas biogênicas (AB) são bases orgânicas tóxicas de baixo peso molecular com estruturas alifáticas, aromáticas ou heterocíclicas, que podem ser encontradas em vários alimentos. Elas são, normalmente, produzidas através da descarboxilação de aminoácidos promovida por micro-organismos (MO). O consumo de alimentos contendo grandes quantidades de AB pode resultar em reações alérgicas caracterizadas por dificuldade de respirar, urticária, vômito e hipertensão. Elas são também conhecidas como possíveis precursores de carcinógenos tais como as N-nitrosaminas. As AB são frequentemente encontradas em altas concentrações nos alimentos e o seu conteúdo não pode ser reduzido por tratamentos térmicos, fato que dificulta a sua redução através dos métodos convencionais de preservação. Uma alternativa para a redução do teor destas substâncias é aplicar a irradiação para induzir a radiólise das AB levando a subprodutos menos tóxicos. DOI: 10.5935/1984-6835.20130018; Biogenic amines (BA) are toxic low molecular weight organic bases with aliphatic, aromatic or heterocyclic structures that can be found in several foods and are mainly produced by microbial decarboxylation of amino acids. The consumption of food containing large amounts of BA can result in allergic reactions...