Métodos cromatográficos para determinar aminas biogênicas em alimentos 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, thin layer and gas chromatography) have been widely applied; however, the food matrix complex requires that changes in the methodology of extraction, derivatization and detection must be performed according to each group of foods. High-performance liquid chromatography is the most widely used chromatographic method applied for biogenic amines in foods. However, due to the current importance of biogenic amines in quality control and consumer safety, researchers try to develop new methods for a fast, reliable analysis of foods in the market. This review presents some chromatographic techniques applied to monitoring BAs in different foods of animal origin.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

Desempenho produtivo e composição da fração proteica do leite de vacas leiteiras sob suplementação com fontes de gordura

The objective of this study was to evaluate the use of fat sources in rations for lactating cows on the productive performance and composition of milk protein fraction. Twelve Holstein cows were used, grouped in three balanced 4 × 4 Latin squares, fed with the following rations: control; refined soybean oil; whole raw soybean; and calcium salts of unsaturated fatty acid (Megalac-E). Dry matter and nutrient intake, and daily milk production were evaluated. The samples used to analyze milk composition were collected in two alternate days and were obtained from two daily milking. Milk composition and total nitrogen, non-protein nitrogen and non-casein nitrogen ratios were analyzed. The casein, serum protein and true protein ratios were obtained by difference. Dry matter and nutrient intakes were lower when cows received the diet containing calcium salts of fatty acids, in relation to the control diet. Among the diets with fat sources, the one with whole raw soybean and calcium salts decreased milk production. There was no effect of fat sources added to the diet on crude protein, non-protein nitrogen, non-casein nitrogen, true protein, casein, casein/milk true protein ratio and serum protein. Similarly, the experimental diets did not influence the protein fractions when expressed in percentage of milk crude protein. The utilization of fat sources in diets changes milk production and composition of lactating cows, but does not influence the composition of milk protein fractions.Objetivou-se com este estudo avaliar a utilização de fontes de gordura em rações para vacas em lactação sobre o desempenho produtivo e a composição da fração proteica do leite. Foram utilizadas 12 vacas da raça Holandesa, agrupadas em três quadrados latinos balanceados 4 × 4, alimentadas com as seguintes rações: controle; óleo de soja refinado; grão de soja in natura; e sais de cálcio de ácidos graxos insaturados (Megalac-E). Avaliaram-se o consumo de matéria seca e de nutrientes, e a produção diária de leite. As amostras utilizadas para análise da composição do leite foram coletadas em dois dias alternados e foram provenientes das duas ordenhas diárias. Foram analisados a composição do leite e os teores de nitrogênio total, nitrogênio não-proteico e nitrogênio não-caseinoso. Por diferença, foram obtidos os teores de caseína, proteína do soro e proteína verdadeira. O consumo de matéria seca e de nutrientes foi menor quando as vacas receberam a ração contendo sais de cálcio de ácidos graxos em relação à ração controle. Entre as rações com fontes de gordura, aquela com grão de soja e sais de cálcio diminuiu a produção de leite. Não houve efeito das fontes de gordura adicionadas nas rações sobre os teores de proteína bruta, nitrogênio não-proteico, nitrogênio não-caseinoso, proteína verdadeira, caseína, relação caseína/proteína verdadeira no leite e proteína do soro. De forma semelhante, as rações experimentais não influenciaram as frações proteicas expressas em porcentagem da proteína bruta do leite. A utilização de fontes de gordura nas rações altera a produção e a composição do leite de vacas em lactação, mas não influencia a composição das frações proteicas do leite

UV-Ozone reactor with modified high pressure mercury vapor lamp for surface treatment of transparent conductive oxides used in electroluminescent polymeric devices

An UV-Ozone reactor was developed with an ignition tube extracted into HID mercury lamp used to irradiation on zinc oxide (ZnO) and fluorinated tin oxide (FTO) films for PLEDs devices. Different exposures times were used. In contact angle measurements revealed better results for ZnO and FTO by 15 and 5 min, respectively. In Diffuse Reflectance Infra-red Fourier Transformed (DRIFT) spectroscopy allowed the observation of water, hydrocarbon and carbon dioxide adsorbed on the untreated TCO surfaces. After the UV-Ozone treatment the contaminants were significantly reduced or eliminated and the PLEDs devices decreased threshold voltages in comparison with respectively untreated TCOs

Evaluation of the Milk Fatty Acid Profile from Mediterranean Buffalo Cows in the First Eight Weeks of Lactation

The aim of this study was to evaluate the fatty acid composition of buffalo milk in the first eight weeks oflactation. It was used 18 cows multiparous Buffaloes of Mediterranean race, the data collection starting four weeksbefore of the calving provided by the 8th week of lactation. The animals were mechanically milked once daily in themorning. The milk samples used for composition analysis were collected weekly from parturition to eight weeks oflactation. There was effect of weeks during the transition period and early lactation for fat yield (kg/day) and for bodyweight of the buffalo cows in lactation (kg).There was effect of weeks of lactation on the fatty acid composition of milkfat.Variations in levels of unsaturated fatty acids of milk fat of buffaloes are similar to those found in dairy cows of thepartum to eighth week of lactation

SISTEMAS DE CULTIVOS NO DESENVOLVIMENTO RADICULAR DA SOJA

One of the characteristics most important in the development ofa culture is the study of the system to root, that ally the different forms ofhandling of the ground, will be able to reflect aspects important of itsperformance. That an experiment with different system of culture in thesoybean was carried through. The treatments had been: conventional system(SC), direct sowing during 5 years (DS5) and direct sowing during 10 years(DS10). Opened 2 trenches for each system and collected the samples of thesoil the culture in full flowering. Each trench had 100 cm of length in theline, enclosing of 10 and 12 plants, with 80 cm of width until reaching toanother line of plantation, consequently eliminating plantation line, withpurpose to inside facilitate to the work of the trench and depth of 60 cm. Theroots had been evaluated by the System Integrated for Analysis of Root deOverture of the Soil. To the long one of the profile of the ground 10 cm andevaluated had been collected samples to each: text of water, density of theground and porosity. The results had allowed to conclude that in theconventional system the roots, in its majority, had been superficial and thatin the system direct plantation, independent of the time, did not havedifferences in the distribution of the roots to the long one of the profile ofthe ground. The density of the ground in the superficial layer was lesser inthe conventional system. The conventional system presented the biggestmacroporosity and small microporosity, being that in the direct independentplantation of the time of this practical it had greater microporosity and lesservalues of macroporosity.Uma das características mais importantes no desenvolvimento deuma cultura é o estudo do sistema radicular, que aliado as formas de manejodo solo, poderá refletir aspectos importantes de seu desempenho. Assim, foirealizado um experimento com alguns sistemas de cultivo na cultura da soja.Os tratamentos foram: sistema convencional (SC), plantio direto durantecinco anos (PD5) e plantio direto durante 10 anos (PD10). Foram abertasduas trincheiras para cada sistema e coletadas amostras de solo com a culturaem pleno florescimento. Cada trincheira tinha 100 cm de comprimentona linha, abrangendo de 10-12 plantas, com 80 cm de largura até alcançar aoutra linha de semeadura, conseqüentemente eliminando linha de semeadura,com finalidade de facilitar o trabalho dentro da trincheira e profundidadede 60 cm. As raízes foram avaliadas pelo Sistema Integrado para Análisede Raízes de Cobertura do Solo (SIARCS). Ao longo do perfil do solo foramcoletadas amostras a cada 10 cm e avaliado: teor de água, densidade do soloe porosidade. Os resultados permitiram concluir que no sistema convencionalas raízes, na sua maioria, foram superficiais e que no sistema plantiodireto, independente do tempo, não houve diferenças na distribuição dasraízes ao longo do perfil do solo. A densidade do solo na camada superficialfoi menor no sistema convencional. O sistema convencional apresentou maiormacroporosidade e menor microporosidade, sendo que no plantio direto, independente do tempo dessa prática, a microporosidade foi maior e menor amacroporosidade

TUBERCULOSE CEREBRAL BOVINA NO OESTE DO PARANÁ – RELATO DE CASO

Uma novilha da raça holandesa foi atendida em Palotina/PR por estar em decúbito lateral e com inapetência, excitabilidade, nistagmo, trismo, opistótono, exoftalmia bilateral, opacidade da córnea direita, prolapso de terceira pálpebra, congestão dos vasos da esclera, espasticidade dos quatro membros e aumento de volume da articulação carpiana e metacarpofalangeana bilateral. Foi realizada eutanásia e o exame macroscópico revelou lesões principalmente na base do tronco encefálico, pequenos nódulos nos ventrículos e espessamento de meninges. À microscopia notou-se infiltrado inflamatório granulomatoso com células gigantes tipo Langhans e vários focos de mineralização. O exame de coloração para bacilos álcool-ácido resistentes Ziehl-Nielsen teve resultado positivo e confirmou a tuberculose cerebral, sendo este o primeiro relato desta forma da doença no oeste do Paraná

The hepatoprotective effect of jaboticaba peel powder in a rat model of type 2 Diabetes Mellitus involves the modulation of thiol/disulfide redox state through the upregulation of glutathione synthesis

Jaboticaba peel powder (JPP) is rich in bioactive compounds, mainly soluble and insoluble polyphenols with great antioxidant properties. ,e aim of this study is to evaluate the effects of JPP supplementation on the oxidative stress and hepatic damage in a rat model of type 2 diabetes mellitus (T2DM). Diabetic rats received vehicle or JPP at 2.7 (JPP-I), 5.4 (JPP-II), or 10.8 (JPP-III) g/L in drinking water during 8 weeks. JPP-III attenuated hyperglycaemia and dyslipidemia increased by 86% the liver content of nonprotein thiol groups and by 90% the GSH/GSSG ratio by activating glutathione synthesis. Accordingly, JPP supplementation prevented the loss of activity of the sulfhydryl-dependent enzyme δ-aminolaevulinic acid dehydratase and attenuated hepatic injury assessed by the reduction of serum aspartate aminotransferase activity and liver hypertrophy. Our results support that JPP supplementation to T2DM rats decreases hepatic damage most likely by increasing glutathione synthesis and modulating the thiol/disulfide redox balance