Ministry of Agriculture

About: Ministry of Agriculture is a government organization based out in Rio de Janeiro, Brazil. It is known for research contribution in the topics: Biology & Chemistry. The organization has 1153 authors who have published 1189 publications receiving 14442 citations.

Method development for the control determination of mercury in seafood by solid-sampling thermal decomposition amalgamation atomic absorption spectrometry (TDA AAS).

Abstract: A very simple and rapid method for the determination of total mercury in fish samples using the Direct Mercury Analyser DMA-80 was developed. In this system, a previously weighted portion of fresh fish is combusted and the released mercury is selectively trapped in a gold amalgamator. Upon heating, mercury is desorbed from the amalgamator, an atomic absorption measurement is performed and the mercury concentration is calculated. Some experimental parameters have been studied and optimised. In this study the sample mass was about 100.0 mg. The relative standard deviation was lower than 8.0% for all measurements of solid samples. Two calibration curves against aqueous standard solutions were prepared through the low linear range from 2.5 to 20.0 ng of Hg, and the high linear range from 25.0 to 200.0 ng of Hg, for which a correlation coefficient better than 0.997 was achieved, as well as a normal distribution of the residuals. Mercury reference solutions were prepared in 5.0% v/v nitric acid medium. Lyophilised fish tissues were also analysed; however, the additional procedure had no advantage over the direct analysis of the fresh fish, and additionally increased the total analytical process time. A fish tissue reference material, IAEA-407, was analysed and the mercury concentration was in agreement with the certified value, according to the t-test at a 95% confidence level. The limit of quantification (LOQ), based on a mercury-free sample, was 3.0 µg kg(-1). This LOQ is in accordance with performance criteria required by the Commission Regulation No. 333/2007. Simplicity and high efficiency, without the need for any sample preparation procedure, are some of the qualities of the proposed method.

Época de colheita e secagem na qualidade de sementes de pimenta Habanero Yellow

Abstract: As pimentas constituem um dos principais produtos da olericultura brasileira. O interesse das industrias por especies picantes, como a pimenta Habanero, tem crescido a cada ano, sobretudo para a producao de molhos e preparados desidratados, o que aumentou a demanda no mercado por sementes de qualidade. O autor teve, atraves desta pesquisa, por objetivo avaliar os efeitos das epocas de colheita das sementes e da secagem na qualidade das sementes de pimenta Habanero Yellow. Foram utilizadas sementes extraidas de frutos em quatro epocas de colheita (E1 - 50, E2 - 60, E3 - 67 e E4 - 67 DAA e mantidos em repouso por 7 dias apos a colheita). As sementes extraidas dos frutos em diferentes epocas de colheita foram submetidas a quatro metodos de secagem: secagem artificial, aos 45 °C, ate 8% de teor de agua; secagem artificial, aos 35 °C, ate 20% de teor de agua, seguida de secagem aos 45 °C, ate 8% de teor de agua; secagem artificial, aos 35 °C, ate 8% de teor de agua; e secagem natural a sombra ate 8% de teor de agua). A qualidade fisiologica das sementes antes da secagem foi avaliada por meio dos testes de germinacao, emergencia e envelhecimento acelerado, alem da analise das isoenzimas esterase, superoxido dismutase, peroxidase, malato desidrogenase, alcool desidrogenase e da endo-β-mananase. Apos a secagem, a qualidade fisiologica das sementes foi avaliada por meio dos testes de germinacao, emergencia e deterioracao controlada. A qualidade fisiologica das sementes e maxima aos 67 DAA, quando os frutos estao completamente maduros. Maiores valores de germinacao e vigor sao observados em sementes secadas aos 35 oC.

HoBi-like is the most prevalent ruminant pestivirus in Northeastern Brazil

Abstract: The ruminant pestiviral species BVDV-1, BVDV-2 and BDV, along with the putative species HoBi-like, may cause substantial economic losses in cattle, sheep and goats. Brazil's large size, variable biomes and wide range of ruminant animal production within different geographic regions suggest that the presence and prevalence of ruminant pestivirus may differ by regions within Brazil. This study investigated the genetic diversity of ruminant pestiviruses and determined the frequency of active infections within two states of the Northeast Region of Brazil, Maranhao and Rio Grande do Norte. Serum samples from 16,621 cattle and 2,672 small ruminants from 569 different herds residing in this region were tested by RT-PCR followed by DNA sequencing. Seventeen positive cattle were detected (0.1%) from fifteen different herds (2.64%). All isolates were classified as HoBi-like pestiviruses based on phylogenetic analysis. All small ruminant samples tested negative. The findings presented herein suggest that the Northeast Region of Brazil has a uniquely high prevalence of HoBi-like viruses. The increasing reports of HoBi-like viruses detected in cattle in the field suggest that natural infection with these viruses may be more widespread than previously thought. The identification of HoBi-like viruses as the most prevalent type of ruminant pestivirus circulating in the Northeast Region of Brazil indicates the need for both continued monitoring and determination of the extent of economic losses associated with HoBi-like virus infections. In addition, it must be taken into account in the choice of diagnostic tests and in vaccine formulations.

Wide-Scope Determination of Pharmaceuticals and Pesticides in Water Samples: Qualitative and Confirmatory Screening Method Using LC-qTOF-MS

Abstract: Aquatic system contamination is a subject of concern due to the high number of contaminants with the potential to be hazardous for plant and animal species, including humans. A large number of analytical methods have been developed to evaluate the extension of water resource pollution, most of them focused on target residue analysis. Screening methods for potential target and non-target compounds are a potential alternative and could be used for a comprehensive evaluation of samples composition. Liquid chromatography coupled to time of flight mass spectrometry (LC-qTOF-MS/MS) was developed to provide full-spectrum data and high mass resolution with appropriate selectivity and sensitivity for monitoring of 300 pharmaceuticals and pesticides in environmental water samples. The validation was based on anti-doping analysis validation protocols, using three different concentration levels (0.01, 0.1, and 1.0 μg L−1). Confirmation analysis was achieved using two fragment ions monitoring for each analyte. Samples were extracted by solid-phase extraction and analyzed by LC-qTOF-MS/MS. The final method was able to detect 170 chemicals in wastewater treatment plant effluent and 198 chemicals in surface water. The advantage of using post-acquisition data processing provided by a qTOF-MS/MS system allowed for non-target analysis for an illicit drug metabolite determination. The method was successfully applied to real samples of wastewater and surface water.