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Pozebon D.,Federal University of Rio Grande do Sul | Dressler V.L.,Federal University of Santa Maria | Marcelo M.C.A.,Federal University of Rio Grande do Sul | de Oliveira T.C.,Laboratorio Nacional Agropecuario LANAGRO | Ferrao M.F.,Federal University of Rio Grande do Sul
Food Additives and Contaminants: Part B Surveillance | Year: 2015

Toxic and nutrient elements were investigated in yerba mate (Ilex paraguariensis) from South America. Fifty-four brands of commercialised yerba mate from Argentina, Brazil, Paraguay and Uruguay were analysed for Al, Ba, Ca, Cu, Fe, K, Mg, Mn, P, Sr, and Zn, using inductively coupled plasma optical emission spectrometry (ICP-OES), and Li, Be, Ti, V, Cr, Ni, Co, As, Se, Rb, Mo, Ag, Cd, Sb, La, Ce, Pb, Bi and U using inductively coupled plasma mass spectrometry (ICP-MS). Antimony, Se, Ag and Bi were not detected in any sample whereas the limits of detection (LODs) of these elements were 0.19, 0.40, 0.003 and 0.001 μg g−1, respectively. Analysis of variance (ANOVA) revealed that the concentrations of Cd, Ti, Ni, As, Mo, U, Li and Be in yerba mate were not statistically different with regard to the country of origin, while those of the other investigated elements differed. © 2015 Taylor & Francis. Source

Ascari J.,Laboratorio Nacional Agropecuario LANAGRO | Dracz S.,Laboratorio Of Residuos Of Medicamento Veterinarios | Santos F.A.,Laboratorio Of Residuos Of Medicamento Veterinarios | Lima J.A.,Laboratorio Of Residuos Of Medicamento Veterinarios | And 2 more authors.
Food Additives and Contaminants - Part A Chemistry, Analysis, Control, Exposure and Risk Assessment | Year: 2012

A quantitative liquid chromatography-tandem mass spectrometry (LC-MS/MS) method for the simultaneous analyses of malachite green (MG), crystal violet (CV) and its major metabolites, leucomalachite green (LMG) and leucocrystal violet (LCV) residues in fish and shrimp samples has been validated. Fish and shrimp samples were extracted with citrate buffer/acetonitrile, and the extracts were purified on strong cation-exchange (SCX) solid-phase extraction (SPE) cartridge. After conversion of LMG into MG using a post column oxidation reactor containing lead (IV) oxide (PbO2), the effluents were analysed. Residues were analysed using positive-ion electrospray ionisation (ESI). Identification and quantification of analytes were based on the ion transitions monitored by multiple reaction monitoring (MRM). Validation of the method was carried out in accordance with the Decision 2002/657/EC, which establishes criteria and procedures for the validation of methods. The following parameters were determined: decision limit (CCα), detection capability (CCβ), linearity, accuracy, precision, selectivity, specificity and matrix effect. The decision limits (CCα) for MG, LMG, CV and LCV were 0.164, 0.161, 0.248 and 0.860 μg kg-1. The respective detection capabilities (CCβ) were 0.222, 0.218, 0.355 and 1.162 μg kg-1. Typical recoveries (intermediate precision) in shrimp, for MG, CV, LMG and LCV for 2.0 μg kg-1 level fortified samples using the optimised procedure were in the range 69%, 97%, 80.3% and 71.8%, respectively. The findings demonstrate the suitability of the method to detect simultaneously MG, CV and its metabolite (LMG and LCV) in fish and shrimp. © 2012 Taylor & Francis. Source

Gouvea R.,Federal University of Fluminense | Santos F.F.,Federal University of Fluminense | Machado L.S.,Federal University of Fluminense | Panzenhagen P.H.N.,Federal University of Fluminense | And 4 more authors.
Arquivo Brasileiro de Medicina Veterinaria e Zootecnia | Year: 2014

Enrofloxacin is one of the most used antibiotics in the poultry industry and the deposition of residues in poultry products, such as eggs, are of great concern to public health. In Brazilian law there is no standard withdrawal period for enrofloxacin in eggs and there is no Maximum Residue Limit (MRL) established for this antimicrobial in eggs. In this study, (Bioo Scientific®) commercial ELISA kit and LC-MS/MS were used to investigate enrofloxacin in eggs of 30 hens pretreated via drinking water at 10mg/kg of enrofloxacin for five days. Six eggs were collected daily and analyzed during treatment and after the end of treatment, for 15 days. Residues obtained maximum levels on the fifth day of treatment, declined gradually and were no longer detected from the ninth day to the end of treatment. Based on the MRL of 100mg/kg established for edible tissues of poultry by Brazillian law and for muscle, fat and skin, by the European Union, after six days of treatment withdrawal, the residue levels were below that limit, with the average of 37.43mg/kg in LC-MS/MS and 14.731mg/kg in ELISA. Within the conditions of this study, a withdrawal period of six days would be more appropriate to use the eggs for human consumption. The values obtained by ELISA for residues in eggs were lower than those obtained in LC-MS/MS for the same sample, however both methods showed statistical agreement. LC-MS/MS is the recommended method by Brazilian legislation for analysis of residues in food, however, according to the results the ELISA kit used can also be applied to the detection of enrofloxacin residues in eggs, with the advantages of speed and simplicity. Source

Magenis R.B.,Federal University of Santa Catarina | Prudencio E.S.,Federal University of Santa Catarina | Fritzen-Freire C.B.,Federal University of Santa Catarina | Stephan M.P.,EMBRAPA - Empresa Brasileira de Pesquisa Agropecuaria | And 2 more authors.
Food Control | Year: 2014

This study was carried out to assess physicochemical (color, moisture, protein and fat content) and rheological properties (fracture stress, fracture strain, degree of solidity and stress decay), as well as to assess the authenticity (using SDS-PAGE) of Minas Frescal cheese in 21 commercial samples acquired in Southern Brazil. Large differences among the samples, which tended to present a yellowish white color were observed. Moisture and protein influenced on the rheological properties and cheeses showed a tendency to being viscous and firm. SDS-PAGE revealed a wide unexpected variability in their proteins profiles and a densitometric casein/β-lactoglobulin ratio allowed to distinguish authentic cheese from adulterated ones. The profiles suggest the irregular presence of whey in the composition of these products, contrary to the enzymatic process legally required. These results emphasize the need for a more effective control, mainly in the selection of raw material, aiming to offer consumers authentic products. © 2014 Elsevier Ltd. Source

Bezerra D.A.M.,Instituto Evandro Chagas | da Silva R.R.,Laboratorio Nacional Agropecuario LANAGRO | Kaiano J.H.L.,Instituto Evandro Chagas | de Souza Oliveira D.,Instituto Evandro Chagas | And 2 more authors.
Avian Pathology | Year: 2014

Rotaviruses infect humans and animals and are classified into eight groups (A to H). Group D rotavirus (RVD) has been described in birds, although relatively few reports are available. The present study focused on RVD, including epidemiological and molecular aspects of samples collected from broiler chickens in the state of Pará, Brazil. A total of 85 faecal samples were collected between 2008 and 2011 from 37 chicken farms located in eight different municipalities. The viral double-stranded RNA was extracted from faecal suspensions and analysed using polyacrylamide gel electrophoresis (PAGE), followed by reverse transcriptase-polymerase chain reaction (RT-PCR) and nucleotide sequencing of the VP6 and VP7 genes. Comparing the positive results, 16.5% (14/85) were obtained by PAGE and 35.3% (30/85) by RT-PCR. Samples from seven of eight municipalities were positive for RVD and infections were recorded in 17 (45.9%) of 37 chicken farms. The RVD infection rate was significantly higher in the 16-day to 30-day age group (62.2%; 23/37) compared with other ages. No consistent relationship was found between the infection rate and either the population density in poultry houses or the climatic conditions. The nucleotide sequences of the VP6 gene were 89.9 to 90.9% similar to the prototype strain 05V0049 and were 88.3 to 100% similar among themselves; VP7 gene nucleotide sequences were 84.3 to 85.4% similar to the prototype strain 05V0049 and 93.8 to 100% similar among themselves. Overall, this study provides new insights into the epidemiology and genome characterization of group D rotaviruses. © 2014 Houghton Trust Ltd. Source

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