Decline of phosphorus, copper, and zinc in anaerobic swine lagoon columns receiving pretreated influent

Land application of both anaerobic lagoon liquid and sludge can increase nutrient accumulation beyond the soils assimilative capacity and become a threat to water quality in regions with intensive, confined swine production. In a 15-month meso-scale column study, we evaluated the effect of manure pretreatment on the reduction of total suspended solids (TSS), total phosphorus (TP), soluble reactive P (SRP), and total copper (Cu) and zinc (Zn) in swine lagoons using (i) enhanced solid-liquid separation (SS) and (ii) solid-liquid separation plus biological nitrogen treatment with nitrification-denitrification (SS + NDN). A conventional anaerobic lagoon treatment was included as a control. A mass flow balance revealed that with both pretreatments the net mass input of TP, Cu, and Zn in the lagoon columns declined 80 to 100 % when compared to the control. Even though both pretreatments significantly reduced P in the inflow, TP and SRP were negatively correlated (r = -0.51 to -0.87) with TSS in the liquid fraction because of the dissolution of P from sludge into the overlying lagoon liquid. On the other hand, the removal of solids by both pretreatments effectively reduced Cu and Zn concentrations in the lagoon liquid, and their concentrations were positively correlated (r = 0.79 to 0.90) with TSS. The decline in mass accumulation of TP, Cu, and Zn in sludge as a result of the reduction of input solids can help minimize both the frequency of sludge removal for lagoon maintenance and the land area for its disposal.

Decline of phosphorus, copper, and zinc in anaerobic swine lagoon columns receiving pretreated influent

Land application of both anaerobic lagoon liquid and sludge can increase nutrient accumulation beyond the soils assimilative capacity and become a threat to water quality in regions with intensive, confined swine production. In a 15-month meso-scale column study, we evaluated the effect of manure pretreatment on the reduction of total suspended solids (TSS), total phosphorus (TP), soluble reactive P (SRP), and total copper (Cu) and zinc (Zn) in swine lagoons using (i) enhanced solid-liquid separation (SS) and (ii) solid-liquid separation plus biological nitrogen treatment with nitrification-denitrification (SS + NDN). A conventional anaerobic lagoon treatment was included as a control. A mass flow balance revealed that with both pretreatments the net mass input of TP, Cu, and Zn in the lagoon columns declined 80 to 100 % when compared to the control. Even though both pretreatments significantly reduced P in the inflow, TP and SRP were negatively correlated (r = -0.51 to -0.87) with TSS in the liquid fraction because of the dissolution of P from sludge into the overlying lagoon liquid. On the other hand, the removal of solids by both pretreatments effectively reduced Cu and Zn concentrations in the lagoon liquid, and their concentrations were positively correlated (r = 0.79 to 0.90) with TSS. The decline in mass accumulation of TP, Cu, and Zn in sludge as a result of the reduction of input solids can help minimize both the frequency of sludge removal for lagoon maintenance and the land area for its disposal.(AU)

Phosphorus distribution and availability in untreated and mechanically separated biogas digestates

Biogas digestates contain valuable nutrients but also have high water contents. Di-gestates were sampled from two different biogas facilities before and after solid-liquid separation and were analyzed with regard to their composition and phosphorus (P) fractions. Additionally, to investigate the P fertilizer effects of these digestates in comparison with undigested slurry or TripleSuper-P (TSP), they were applied in a pot experiment (6 kg soil per pot) in an amount corresponding to 200 mg P per pot in combination with various crops (amaranth, maize, maize + beans mixed cropping, sorghum). A separation of digestates resulted in higher P concentrations of the solid fraction in comparison with the liquid fraction. The proportion of the readily soluble P fractions (H2O-P, NaHCO3-P) to the total P was higher than 70 % in all digestates. The digestates increased P uptake of the tested crops and concentrations of bioavailable P in the soil to the same extent as highly soluble TSP. Activities of soil enzymes were lower after application of the digestates in comparison to unfermented slurry. The fertilizer management of digestates can be improved by a solid-liquid separation since the solid fraction showed a relatively high concentration of P resulting in a reduction in application doses required to meet the P demands of crops.

Phosphorus distribution and availability in untreated and mechanically separated biogas digestates

Biogas digestates contain valuable nutrients but also have high water contents. Di-gestates were sampled from two different biogas facilities before and after solid-liquid separation and were analyzed with regard to their composition and phosphorus (P) fractions. Additionally, to investigate the P fertilizer effects of these digestates in comparison with undigested slurry or TripleSuper-P (TSP), they were applied in a pot experiment (6 kg soil per pot) in an amount corresponding to 200 mg P per pot in combination with various crops (amaranth, maize, maize + beans mixed cropping, sorghum). A separation of digestates resulted in higher P concentrations of the solid fraction in comparison with the liquid fraction. The proportion of the readily soluble P fractions (H2O-P, NaHCO3-P) to the total P was higher than 70 % in all digestates. The digestates increased P uptake of the tested crops and concentrations of bioavailable P in the soil to the same extent as highly soluble TSP. Activities of soil enzymes were lower after application of the digestates in comparison to unfermented slurry. The fertilizer management of digestates can be improved by a solid-liquid separation since the solid fraction showed a relatively high concentration of P resulting in a reduction in application doses required to meet the P demands of crops.(AU)

Avaliação histomorfológica do tecido testicular de gatos domésticos impúberes após vitrificação / Histomorphological evaluation of testicular tissue from prepubertal cats after vitrification

The aim of this study was to evaluate prepubertal cats testicular tissue histomorphology aftervitrification. Five testicular pairs from five prepubertal cats were used. The fragments were distributed in thecontrol group and vitrification group containing association of the cryoprotectants ethylene glycol and glycerolin a final concentration of 5.6M. Testicular fragments of the control group were fixed in Bouin solution,processed for histomorphological evaluation and stained with hematoxylin-eosin. Then, the fragments ofvitrification group were subjected to a solid surface vitrification and stored in liquid nitrogen. The fragmentswere thawed and processed for histology similarly to the control group. The control group was superior to thevitrification group regarding to the basal membrane separation cell, cell differentiation, visibility of the nucleusand nuclear condensation. Regarding the shrinkage of the basal membrane, there were no differences betweenthe groups. Morphological analysis of prepubertal cats testicular tissue after vitrification can contribute toimprove the reproductive biotechnologies applied to felines.(AU)

Avaliação histomorfológica do tecido testicular de gatos domésticos impúberes após vitrificação / Histomorphological evaluation of testicular tissue from prepubertal cats after vitrification

The aim of this study was to evaluate prepubertal cats’ testicular tissue histomorphology aftervitrification. Five testicular pairs from five prepubertal cats were used. The fragments were distributed in thecontrol group and vitrification group containing association of the cryoprotectants ethylene glycol and glycerolin a final concentration of 5.6M. Testicular fragments of the control group were fixed in Bouin solution,processed for histomorphological evaluation and stained with hematoxylin-eosin. Then, the fragments ofvitrification group were subjected to a solid surface vitrification and stored in liquid nitrogen. The fragmentswere thawed and processed for histology similarly to the control group. The control group was superior to thevitrification group regarding to the basal membrane separation cell, cell differentiation, visibility of the nucleusand nuclear condensation. Regarding the shrinkage of the basal membrane, there were no differences betweenthe groups. Morphological analysis of prepubertal cats’ testicular tissue after vitrification can contribute toimprove the reproductive biotechnologies applied to felines.

Endocrine disruptors in water filters used in the Rio dos Sinos Basin region, Southern Brazil / Disruptores endócrinos em filtros de água utilizados na região da Bacia Hidrográfica do Rio dos Sinos no Sul do Brasil

The activated carbon filter is used in residences as another step in the treatment of drinking water, based on a physical-chemical process to absorb pollutants that are not removed in conventional treatment. Endocrine disruptors (EDCs) are exogenous substances or mixtures of substances that acts on the endocrine system similarly to the endogenously produced hormones, triggering malfunctions and harmful changes to human and animal health. The objective of the present work was to study EDCs through semi-quantitative analysis of residential water filters collected in the region of Rio dos Sinos basin, focusing on two specific classes: hormones and phenols. The solid phase extraction principle was used for the extraction of compounds and gas chromatography coupled with mass spectrometry for the separation and characterization of EDCs. Four samples of residential filters collected from public water distribution and artesian wells, from the cities of Novo Hamburgo and São Leopoldo were analysed. Using the developed methodology, it was possible to detect and comparatively quantify selected EDCs in all studied samples, which indicates the presence of these contaminants in drinking water from different sources.(AU)

O filtro de carvão ativado é utilizado em residências como mais uma etapa no processo de tratamento da água potável, tendo como base um processo físico-químico para adsorção de poluentes presentes na água que não são removidos no tratamento convencional. Os Disruptores Endócrinos (DEs) são substâncias ou misturas exógenas que atuam no sistema endócrino de maneira similar aos hormônios produzidos endogenamente, desencadeando disfunções e alterações nocivas à saúde humana e animal. O objetivo do presente trabalho foi estudar DEs através da análise semi-quantitativa de amostras de filtros de água coletados na região da bacia do Rio dos Sinos focando em duas classes químicas: hormômios estrogênicos e fenóis. Foram utilizados os princípios da técnica de extração em fase sólida (SPE) para a extração dos compostos, e cromatografia gasosa acoplada à espectrometria de massas para a separação e detecção de DEs. Foram analisadas quatro amostras de filtros residenciais provenientes de água tratada e água de poço artesiano, das cidades de Novo Hamburgo e São Leopoldo. Com o método desenvolvido foi possível detectar e quantificar comparativamente DEs selecionados em todas as amostras estudadas, o que indica a presença desses contaminantes na água de consumo humano oriunda de diferentes fontes. (AU)

Viabilidade técnica do emprego de solventes alcoólicos na extração de óleos vegetais: caracterização físico-química do óleo, funcionalidades da fração proteica e recuperação do solvente

Durante o desenvolvimento da presente Tese de Doutorado buscou-se como objetivo principal o estudo da viabilidade técnica da substituição do solvente utilizado no processo industrial de extração de óleos vegetais, hexana, por álcoois de cadeia curta, etanol ou isopropanol, com diferentes graus de hidratação, sendo estes considerados mais seguros frente à alta toxicidade e inflamabilidade da hexana. Ainda, estes solventes alcoólicos podem ser parcialmente recuperados após o processo de extração devido apresentarem miscibilidade parcial com óleo à temperatura ambiente. Buscando-se aumentar o rendimento de extração de óleo e agregar valor ao material desengordurado rico em proteínas, a torta de sementes de gergelim foi submetida ao processo de extração alcoólica utilizando-se etanol ou isopropanol, absoluto ou azeotrópico, nas temperaturas de 50 a 90 °C. Resultados mostraram que a hidratação do solvente alcoólico afetou negativamente a eficiência de extração de óleo, enquanto o aumento da temperatura favoreceu este processo, com valores de rendimento de extração de aproximadamente 98 % sendo atingidos para solventes absolutos a 90 °C, considerando um único estágio de contato. O óleo de torta de sementes de gergelim obtido da extração alcoólica mostrou-se rico em sesamina, contendo aproximadamente 4 g/kg deste composto, independentemente do tipo de solvente e temperatura. Isopropanol absoluto exibiu a melhor capacidade de extração de tocoferóis, permitindo obter óleo de torta de sementes de gergelim com 177 mg/kg deste composto minoritário. Em adição, independentemente da condição de processo empregada, o óleo obtido da extração alcoólica apresentou composição típica de óleo de sementes de gergelim. Em relação à fração proteica, a utilização de temperaturas variando de 50 a 80 °C, para todos os solventes alcoólicos estudados, não afetou a solubilidade proteica e a estabilidade térmica dos sólidos desengordurados. Para o farelo de arroz, os baixos valores de índice de solubilidade obtidos, cerca de 10 %, inviabilizaram a produção de concentrados proteicos e, portanto, o impacto das condições de extração sobre as propriedades funcionais dos materiais desengordurados oriundos da extração alcoólica sequencial de óleo de farelo de arroz, a 60 e 80 °C, foi avaliado. Altos valores de capacidade de absorção de água (4 g/g amostra) e óleo (3 g/g amostra) foram obtidos, denotando a possibilidade da aplicação deste material em produtos de panificação e cárneos, respectivamente. Em adição, observou-se que o processo de extração alcoólica não interferiu na estabilidade das espumas produzidas, porém exerceu influência negativa na estabilidade das emulsões. Ademais, no estudo da recuperação do solvente, etapa subsequente ao processo de extração, dados de equilíbrio de fases determinados para sistemas lipídicos compostos por óleo bruto de sementes de gergelim, obtido da prensagem mecânica industrial, e solventes alcoólicos, entre 10 e 60 °C, mostraram que a temperatura influenciou fracamente a solubilidade mútua dos componentes do sistema, enquanto a hidratação do solvente causou uma diminuição desta solubilidade, com consequente redução do coeficiente de partição para o óleo e ácidos graxos livres. Parâmetros do modelo NRTL ajustados aos dados experimentais apresentaram adequada descrição do comportamento dos sistemas lipídicos, com desvios variando de 0,15 a 0,49 %. Em adição, buscando-se associar os resultados obtidos nos experimentos de extração alcoólica de óleo de torta de sementes de gergelim aos dados de equilíbrio líquido-líquido observou-se que os parâmetros estimados para os sistemas lipídicos contendo etanol e isopropanol conseguiram prever adequadamente os teores de sólidos solúveis contidos nas fases extrato oriundas dos experimentos de extração sólido-líquido nos quais Et0 e IPA12 foram utilizados como solventes. Ainda, os parâmetros de interação binários estimados foram utilizados para determinação da proporção mássica mínima de óleo:solvente no extrato que possibilitaria dessolventização parcial, devido à separação de fases com a redução da temperatura, sendo encontrados valores de 1:5 para Et0, 1:3 para IPA0 e 1:1 para os álcoois mais hidratados, Et6 e IPA12.

During the development of this Ph.D. Thesis, the main objective was to study the technical feasibility of replacing the solvent used in the industrial process of vegetable oils extraction, hexane, by short chain alcohols, ethanol or isopropanol, with different degrees of hydration, which are considered safer due to the hexane high toxicity and flammability. Also, these alcoholic solvents can be partially recovered after the extraction process due to partial miscibility with oil at room temperature. In order to increase the oil extraction yield and add value to the protein-rich defatted meal, sesame seed cake was submitted to the alcoholic extraction process using ethanol or isopropanol, absolute or azeotropic, at temperatures from 50 to 90 °C. Results showed that the hydration of the alcoholic solvent negatively affected the oil extraction efficiency, while the increase in temperature favored this process, with extraction yield values of approximately 98 % being reached for absolute solvents at 90 °C, considering a single stage of contact. The sesame seed cake oil obtained from alcoholic extraction was rich in sesamin, containing approximately 4 g/kg of this compound, regardless of the alcohol hydration and temperature. Absolute isopropanol exhibited the best tocopherol extraction capacity, enabling to obtain sesame seed cake oil with 177 mg/kg of this minor compound. In addition, regardless of the process condition employed, the oil obtained from the alcoholic extraction showed a typical composition of sesame seed oil. Regarding the protein fraction, the use of temperatures ranging from 50 to 80 °C, for all alcoholic solvents studied, did not affect the protein solubility and the thermal stability of the defatted meals. For the rice bran, the low values of solubility index obtained, about 10 %, made the production of protein concentrates unfeasible and, therefore, the impact of the extraction conditions on the functional properties of the defatted meals from the sequential alcoholic extraction of rice bran oil, at 60 and 80 °C, was evaluated. High values of water (4 g/g sample) and oil (3 g / g sample) absorption capacities were obtained, denoting the possibility of applying this material to bakery and meat products, respectively. In addition, it was observed that the alcoholic extraction process did not interfere in the stability of the foams produced, but had a negative influence on the stability of the emulsions. Furthermore, in the solvent recovery study, a subsequent step from the extraction process, phase equilibrium data determined for lipid systems composed of crude sesame seed oil, obtained from industrial mechanical pressing, and alcoholic solvents, at temperatures of 10 to 60 °C, showed that the temperature weakly influenced the mutual solubility of the system components, while the solvent hydration caused a decrease of this solubility, with consequent reduction of the partition coefficient for the oil and free fatty acids. NRTL model parameters adjusted to the experimental data presented an adequate description of the lipid systems behavior, with deviations varying from 0.15 to 0.49 %. In addition, looking for associate the results obtained in the alcoholic extraction of sesame seed cake oil with the liquid-liquid equilibrium data, it was observed that the parameters estimated for the lipid systems containing ethanol and isopropanol were able to adequately predict the contents of soluble solids in the extract phases from the solid-liquid extraction experiments in which Et0 and IPA12 were used as solvents. Moreover, the estimated binary interaction parameters were used to determine the minimum oil:solvent mass ratio in the extract that would allow partial desolventization, due to the phase separation with the reduction of temperature, with values of 1:5 being found for Et0, 1:3 for IPA0 and 1:1 for the more hydrated alcohols, Et6 and IPA12.

Estudo dos equilíbrios sólido-líquido presentes na síntese enzimática de antibióticos -lactâmicos

Os antibióticos -lactâmicos constituem a classe de medicamentos mais prescrita na medicina humana e veterinária. No Brasil, destacam-se entre eles, a amoxicilina e ampicilina, como sendo os dois antibióticos mais consumidos e importados pelo país. A dependência do Brasil por países produtores destes fármacos é decorrente dos inconvenientes causados pela rota química convencional de síntese, que utiliza grande quantidade de solventes tóxicos gerando resíduos não biodegradáveis. Diante disso, a síntese enzimática vem se destacando como uma rota alternativa e limpa. Contudo, para esta rota tornar-se economicamente viável e competitiva, é necessário estudar a separação do antibiótico do meio reacional, visto que o mesmo depois de formado encontra-se disponível à degradação hidrolítica, reduzindo o rendimento do processo. A escolha de um agente adequado de separação requer o conhecimento do comportamento dos constituintes nas fases envolvidas em diferente s condições operacionais. Baseado nisso, este trabalho focou na determinação da solubilidade da amoxicilina, ampicilina e seus respectivos subprodutos da síntese enzimática em diferentes condições de temperatura (10 25 °C), pH (3 8) e concentração de etanol (0 70% m/m), usando o método analítico com espectroscopia. Para melhor entendimento destes compostos em solução, foram determinadas as constantes de dissociação de cada um a partir de curvas potenciométricas. Com isso, novos dados de equilíbrio químico e de fases foram apresentados. Os resultados obtidos concordaram com os fundamentos que regem o equilíbrio sólido-líquido entre biomoléculas no que diz respeito à influência do pH, temperatura e solventes orgânicos, e destacam a influência das cargas elétricas em suas propriedades. Além disso, os parâmetros termodinâmicos (H, S e G) das reações de dissociação destes compostos em solução foram determinados, indicando que as moléculas protonadas são mais estáveis. Por fim, um modelo termodinâmico considerando a idealidade da solução, e uma modificação do mesmo aplicando a não idealidade foram aplicados para descrever matematicamente as curvas de solubilidade obtidas experimentalmente. Ambos os modelos concordaram com precisão a solubilidade dos compostos nas condições estudadas, exceto nas condições em que a ampicilina apresentou polimorfismo, indicando que em alguns casos a abordagem ideal pode fornecer informações satisfatórias de determinados sistemas, sem a necessidade da estimação de parâmetros. Solubilidade, antibiótico -lactâmico, constante de dissociação, modelagem

The -lactam antibiotics constitute the class of most prescribed drugs in human and veterinary medicine. In Brazil, it stands out among them, amoxicillin and ampicillin, as the two most consumed antibiotics and imported by the country. The dependence of Brazil by producing countries of these drugs is due to the disruption caused by conventional chemical synthesis, which uses large amounts of toxic solvents generating non-biodegradable waste. Thus, the enzymatic synthesis has been highlighted as an alternative and "clean" route. However, this route to become economically viable and competitive, it is necessary to consider the separation of the antibiotic from the reaction medium, since even after formed it is subject to hydrolytic degradation, reducing process yield. The choice of a suitable separation agent requires the knowledge of the constituents behavior in the phases involved at different operating conditions. Based on this, this work has focused on determining the solubility of amoxicillin, ampicillin and their by-products of enzymatic synthesis under different temperature (10 25 °C), pH (2 8) and ethanol concentration conditions (0 70% wt) using the spectroscopic analytical method. For a better understanding of these compounds in solution were determined dissociation constants of each from potentiometric curves. Therefore, new chemical and phase data were presented. The results obtained agreed with the fundamentals governing the solid-liquid equilibrium among biomolecules regarding the influence of pH, temperature and organic solvents, and highlight the influence of the electric charges on their properties. Furthermore, the thermodynamic parameters (H, S e G) of dissociation reactions of these compounds in solution were determined, indicating that the protonated molecules are more stable. Finally, a thermodynamic model considering the ideal solution, and a modification one thereof by applying the non-ideality were. Both models agreed with accuracy the solubility of the compounds under the conditions studied, except the conditions in which ampicillin showed polymorphism. This means that the ideal approach can provide satisfactory information in some systems, without the need of estimating parameters.

Methodological optimization for determination of benzo(a)pyrene in cachaças by HPLC with fluorescence detection and evaluation of its occurrence / Otimização de metodologia para determinação de benzo(a)pireno em cachaças por CLAE com detecção de fluorescência e avaliação de sua ocorrência

The objectives of the present study were to compare, to adapt and to validate analytical methodology for identification, and quantification of benzo(a)pyrene (BaP) in cachaça samples by HPLC-DFl and confirmation by GC/MS; also, to evaluate the BaP levels in cachaças commercialized in São Paulos market, and to verify which stages of one production of still cachaça could contribute for BaP contamination. Three distinct methods for BaP extraction were studied: solid phase extraction (SFE), liquid-liquid extraction with cyclohexane (LLE-CHX) and liquid-liquid extraction with N,N dimethyllformamideand cyclohexane (LLE-DMF/CHX). SFE extraction used a C18 cartridge in silica base (500mg, 6 mL) and cyclohexane, while the LLE consisted on sample partition in appropriate solvent and purification by column chromatography on silica gel. The extracts obtained from all extractions were evaporated to dryness, reconstituted in acetonitrile and analyzed by HPLC-DFl. Chromatography separation was carried out on a column C18 (25 cm; 0.45 m; 4.6 mm) using acetonitrile/water (70:30) as mobile phase at a flow rate of 1mL/min. The response of fluorescence detector was linear for BaP standard solutions ranging from 0.05 to 30 ppb (R2=0.9995). The detection and quantification limits were 0.03 ppb and 0.1 ppb for all methods. Recoveries values at 3 concentration levels (0.1, 1.0, 3.0 ppb) (n=3) ranged

iptesenta resumo em inglês.

Desenvolvimento de um sistema para o pré-processamento da cama de frangos de corte destinada a biodigestão anaeróbia e compostagem "in-vessel"

Objetivou-se avaliar o desempenho de um equipamento de préprocessamento de cama de frangos de corte (CF), para avaliar as diluições de CF + água, em relação a teor de sólidos e o efeito da CF, da fração líquida (FL), da fração sólida (FS) na biodigestão anaeróbia (BA) utilizando biodigestores batelada e contínuos em diferentes tempos de retenção hidráulica. O desempenho da CF, da FS do préprocessamento e da carcaça de aves, foram avaliadas (produção de biogás e adubo orgânico) em um protótipo de compostagem ?in-vessel?. Foram dimensionados plantas de biogás, para análise de viabilidade econômica de unidades de tratamento e aproveitamento energético de resíduos avícolas. O pré-processamento se mostrou adequado para utilização em unidades de tratamento e aproveitamento energético da cama de frangos de corte, concentrando alguns nutrientes, em especial o nitrogênio e o carbono, apresentando resultados de sólidos totais interessantes para BA da FL, nas diluições de 1:5 a 1:10 (CF+Água). O pré-processamento proporciona 0,418 m3/kg SVadic, caso seja realizado a separação de sólidos e a BA das FL e FS separadas, o que representa 55,3 % acima do valor obtido sem a separação de frações (0,231 m3/kg SV). O tempo de retenção hidráulica de 24 dias apresentou maiores produções de biogás (0,443 m3/kgST ou 0,504 m3/kgSVadic), indicando que quanto menor o tempo de retenção hidráulica da fração líquida nos biodigestores continuos, maiores serão os ganhos com biogás. O protótipo foi eficiente no tratamento acelerado dos resíduos de carcaça de aves, cama de frango e fração sólida. A inclusão de passos anaeróbios no processo de compostagem aumentou a velocidade de degradação da matéria orgânica (82,88 % ST), diminuindo o tempo de tratamento do resíduo, o qual pode ser tratado em 30 dia, horas de...

This study aimed to evaluate the performance of a hardware preprocessor litter poultry (CF) to evaluate the water dilutions + CF, compared to solids and the effect of CF, the liquid fraction (FL ), the solid fraction (SF) in anaerobic digestion (BA) using continuous and batch digesters at different hydraulic retention times. The performance of CF, the FS preprocessing and poultry carcasses were evaluated (biogas and organic fertilizer) in a prototype composting "in-vessel". Were sized biogas plants, to analyze the economic feasibility of treatment units and energy recovery from poultry waste. The preprocessing is adequate for use in treatment units and energy recovery bed of broilers, concentrating some nutrients, especially nitrogen and carbon, presenting results of total solids of interest to BA FL, at dilutions of 1:5 to 1:10 (CF + water). The preprocessor provides 0.418 m3/kg SVadic, if carried out the separation of solids and BA separate FL and FS, which is 55.3% above the value obtained without separation of fractions (0.231 m3/kg VS). The hydraulic retention time of 24 days showed higher biogas production (0.443 m3/kgST or 0.504 m3/kgSVadic), indicating that the lower the hydraulic retention time of the liquid fraction in continuous digesters, the greater the gains from biogas. The prototype was effective in the treatment of accelerated waste of poultry carcasses, poultry litter and solid fraction. The inclusion of steps anaerobic in the composting process increased the rate of degradation of organic matter (82.88% ST), decreasing the treatment time of residue, which can be treated on 30 days, hours of operation (22.95% methane). Finally, there is the economic feasibility for installation of biogas plants on farms with two and four broiler sheds, with "payback" at 6.2 and 3.6 years, respectively. The values of the digester...

Desenvolvimento de métodos analíticos visando atender aos princípios da química verde na análise de resíduos de medicamentos veterinários em leite bovino / Development of analytical methods to attend the green chemistry principles in the analysis of veterinary medicines in bovine milk

A utilização de medicamentos veterinários é de grande importância na produção animal, porém também pode trazer conseqüências negativas, como a presença de resíduos em alimentos, como o leite bovino. As sulfonamidas são uma classe de antibióticos utilizados no tratamento veterinário e humano, sendo de grande importância sua análise em alimentos de origem animal, como o leite, uma vez que podem provocar resistência bacteriana, reações alérgicas e intoxicações, comprometendo a segurança alimentar da população e prejudicando a fabricação de derivados lácteos. A maioria dos estudos vem utilizando a extração em fase sólida (SPE), na extração das sulfonamidas e no clean up da amostra. Entretanto, o método QuEChERS, introduzido em 2003, vem sendo considerado promissor na extração de diversos compostos em matrizes alimentícias. Assim, a presente pesquisa teve o objetivo de desenvolver e validar métodos analíticos, comparando os métodos de extração SPE e QuEChERS, com posterior análise por cromatografia líquida de alta eficiência com detecção de arranjo de diodos, para a determinação de sulfonamidas (sulfatiazol, sulfametazina e sulfadimetoxina) em leite bovino. Na otimização das condições cromatográficas e do método de extração QuEChERS, utilizou-se planejamentos experimentais. Primeiramente, foram otimizadas as condições cromatográficas, selecionando-se coluna C18 Luna (100 x 4,6 mm, 5 µm), 17 µL de volume de injeção, comprimento de onda de 290 nm, vazão de 0,50 mL min-1, temperatura de 20 °C e eluição gradiente com os solventes água e etanol. No método de extração QuEChERS, o procedimento otimizado utilizou 6 g de leite, 3 mL de água, 6 mL de acetonitrila contendo 1% de ácido acético, 2,4 g de MgSO4 e 0,6 g de acetato de sódio, sendo que na etapa de clean up da amostra utilizou-se 37,5 mg de amina primária e secundária, 25 mg de octadecilsilano e 150 mg de MgSO4. O planejamento experimental foi considerado eficiente na otimização das condições cromatográficas e no procedimento de extração QuEChERS, obtendo-se boa separação entre os picos e valores de recuperação entre 95 e 98%, com desvio padrão relativo inferior a 8,25% para os analitos na concentração de 0,05 mg kg-1. No desenvolvimento do método de extração SPE não foi possível obter boa recuperação dos analitos e clean up da amostra. Acredita-se que as sulfonamidas estudadas sejam perdidas na etapa de pré-tratamento do leite, a qual é importante para a realização da SPE. Desse modo, a extração usando o QuEChERS foi selecionada para a análises das sulfonamidas em leite bovino. Os ensaios de validação demonstraram que o método é adequado para a análise das sulfonamidas, dentro do limite máximo de resíduos (0,1 mg kg-1), estabelecido pela Agencia Nacional de Vigilância Sanitária, com exatidão e precisão dentro da faixa aceitável pelos guias de validação seguidos. Além disso, foi possível utilizar apenas etanol e água como fase móvel cromatográfica, o que é uma vantagem em relação a métodos tradicionais, pois utiliza um solvente orgânico menos tóxico e renovável. A vazão de fase móvel é relativamente baixa, o que contribui para a diminuição do volume de solvente orgânico consumido e de resíduos gerados

The use of veterinary medicines is of great importance in animal production, but also can have negative consequences, such as the occurrence of residues in food of animal origin, among which bovine milk stands out. Sulfonamides are an antibiotic class used in animal and human treatments, so it is important to analyze this kind of residue in food of animal origin, such as milk, because it can cause allergic reactions and poisoning, affecting food safety and damaging the manufactory of dairy products. Most of the studies have used solid-phase extraction (SPE) in the extraction of sulfonamides and clean up of the sample. However, the QuEChERS method, introduced in 2003, has been considered promising in the extraction of various compounds in food matrices. Thereby, this research aimed to develop and validate analytical methods comparing the extraction methods SPE and QuEChERS, followed by high performance liquid chromatography with diode array detection for the analysis of sulfonamides (sulfathiazole, sulfamethazine and sulfadimethoxine) in bovine milk. In the optimization of the chromatographic conditions and QuEChERS method, we used experimental design. Chromatographic conditions were optimized, selecting column C18 Luna (100 x 4.6 mm, 5 µm), injection volume of 17 µL, wavelength of 290 nm, flow rate of 0.5 mL min-1, temperature of 20 °C and gradient mode, using water and ethanol as mobile phase. In the QuEChERS method, the optimized procedure used 6 g of milk, 3 mL of water, 6 mL of acetonitrile with 1% of acetic acid, 2.4 g of MgSO4 and 0.6 g of sodium acetate, and in the clean up step it was used 37.5 mg of primary and secondary amine, 25 mg of octadecylsilane and 150 mg of MgSO4. Experimental design was considered efficient in the optimization, since it was obtained good separation of the chromatographic peaks and recovery between 95 and 98% with relative standard deviation below 8.25% for the analytes in the concentration of 0.050 mg kg-1. In the development of the extraction method SPE, it was not possible to obtain good recovery for the analytes and clean up of the sample. It is believed sulfonamides are lost in the sample pre-treatment step, which is important in performing SPE. Therefore, the QuEChERS method was selected for this analysis. The validation tests demonstrate the method is appropriate, within the maximum limit residue (0.1 mg kg-1), established by the National Health Surveillance Agency, with accuracy and precision within the accepted limit, according to the followed validation guides. Moreover, it was possible to use just water and ethanol as mobile phase, what is an advantage in relation to traditional methods, because it uses an organic solvent less toxicant and renewable. Rate flow is also relatively low, which contributes to decrease the required volume of organic solvent and the amount of waste produced

Desempenho de um hidrociclione de geometria "rietema" como pré filtro para sistemas de irrigação

Os hidrociclones são equipamentos amplamente utilizados pela indústria em processos envolvendo separação sólido-líquido, porém, ainda, pouco divulgados na agricultura irrigada brasileira. Buscou-se neste trabalho determinar a perda de carga e avaliar o desempenho de um hidrociclone de geometria ?Rietema? como pré-filtro de partículas sólidas. Os testes foram realizados no Centro Federal de Educação Tecnológica de Uberaba - MG - Brasil utilizando um hidrociclone de geometria ?Rietema?. Este equipamento possui um diâmetro de 19,20 cm na parte cilíndrica e opera com vazões variando entre 10 m3 h-1 e 27 m3 h-1. Os materiais particulados usados em suspensão foram: solo franco-argiloso e areia de rio. Os resultados mostraram que a perda de carga máxima média foi de 52 kPa e 47 kPa para as suspensões aquosas de areia e solo, respectivamente. Seu melhor desempenho ocorreu operando com suspensão aquosa de areia, apresentando eficiência total de 92,31% para a vazão de 26,97 m3 h-1. Dentre as conclusões pode-se inferir que o equipamento avaliado é eficiente para remoção de partículas de areia, podendo ser utilizado como pré-filtro em sistemas de irrigação

The hydrocyclones are equipments widely used by industry in cases involving solid-liquid separation, but still, little reported in brazilian irrigated agriculture. The proposal of this research was to determining the head loss and evaluate the performance of a hydrocyclone of geometry ?Rietema? as a pre-filter of solid particles. The tests were performed in the Centro Federal de Educação Tenológica de Uberaba - MG - Brazil using a hydrocyclone of Rietema geometry. This equipment has a diameter of 19.20 cm at the cylindrical part and operates with flows ranging between 10 m3 h-1 and 27 m3 h-1. The materials used in particulate suspension were: clay loam soil and sand from river. The results showed that the average maximum head loss was 52 kPa and 47 kPa of aqueous suspensions of sand and soil, respectively. Its best performance occurred operating with slurry of sand, presenting total efficiency of 92.31% for flow rate of 26.97 m3 h-1. Among the conclusions can be inferred that the equipment is judged effective at removing particles of sand and can be used as pre-filter in irrigation systems

Methodological optimization for determination of benzo(a)pyrene in cachaças by HPLC with fluorescence detection and evaluation of its occurrence / Otimização de metodologia para determinação de benzo(a)pireno em cachaças por CLAE com detecção de fluorescência e avaliação de sua ocorrência

The objectives of the present study were to compare, to adapt and to validate analytical methodology for identification, and quantification of benzo(a)pyrene (BaP) in cachaça samples by HPLC-DFl and confirmation by GC/MS; also, to evaluate the BaP levels in cachaças commercialized in São Paulos market, and to verify which stages of one production of still cachaça could contribute for BaP contamination. Three distinct methods for BaP extraction were studied: solid phase extraction (SFE), liquid-liquid extraction with cyclohexane (LLE-CHX) and liquid-liquid extraction with N,N dimethyllformamideand cyclohexane (LLE-DMF/CHX). SFE extraction used a C18 cartridge in silica base (500mg, 6 mL) and cyclohexane, while the LLE consisted on sample partition in appropriate solvent and purification by column chromatography on silica gel. The extracts obtained from all extractions were evaporated to dryness, reconstituted in acetonitrile and analyzed by HPLC-DFl. Chromatography separation was carried out on a column C18 (25 cm; 0.45 m; 4.6 mm) using acetonitrile/water (70:30) as mobile phase at a flow rate of 1mL/min. The response of fluorescence detector was linear for BaP standard solutions ranging from 0.05 to 30 ppb (R2=0.9995). The detection and quantification limits were 0.03 ppb and 0.1 ppb for all methods. Recoveries values at 3 concentration levels (0.1, 1.0, 3.0 ppb) (n=3) ranged

iptesenta resumo em inglês.

Residuos de antimicrobianos em peixe : depleção residual e desenvolvimento de metodos analiticos / Antimicrobials residues in fish : residual depletion and development of analytical methods

Os antimicrobianos são largamente empregados na medicina veterinária, e resíduos destes podem permanecer nos alimentos de origem animal, acima de valores considerados seguros, quando não são respeitadas as boas práticas veterinárias. Este trabalho teve por objetivos: (i) desenvolver e validar métodos analíticos para a determinação de multi-resíduos de quinolonas (enrofloxacina, ciprofloxacina, danofloxacina, sarafloxacina, ácido oxolínico e flumequina) em carne de peixe, usando a cromatografia líquida de alta eficiência associada a detecção por fluorescência (HPLC-FL) e cromatografia líquida associada a espectrometria de massas em tandem por interface de ionização por electrospray e (LC-ESI-MS/MS Q-ToF); (ii) desenvolver e validar métodos analíticos para a determinação de oxitetraciclina (OTC) em ração e carne de tilápias por HPLC-DAD e HPLC-FL, respectivamente e (iii) realizar um ensaio com tilápias (Oreochromis niloticus) para avaliar a depleção da OTC na carne desses peixes. De modo geral, a extração das quinolonas e da OTC da carne de peixes foi conduzida por extração sólido líquido seguida da limpeza do extrato em cartuchos de extração em fase sólida. A separação cromatográfica dos antimicrobianos foi realizada em coluna de fase reversa octadecil híbrida. Os métodos foram validados mediante avaliação dos seguintes parâmetros: faixa linear, linearidade, sensibilidade, seletividade, limites de detecção e quantificação, precisão intra e inter-ensaios e exatidão. Para o método LC-MS/MS foi também avaliado o efeito matriz. Todos os métodos foram considerados adequados aos objetivos propostos neste trabalho. Para avaliar a depleção de OTC na carne de tilápias, os peixes (peso médio de 93 a 115 g) receberam o fármaco via ração na dose de 80 mg OTC/kg peso vivo/dia, por cinco dias consecutivos. A temperatura da água durante o ensaio variou de 16,5 a 24,5 °C. A curva de depleção se ajustou a um modelo exponencial de primeira ordem. O tempo de meia vida de eliminação foi de 2,5 dias e o período de carência estimado foi de 5 dias

Antimicrobials are widely employed in veterinary medicine, and their residues could remain in food of animal origin above values considered safe if good veterinary practices are not followed. The aim of this work is to address (i) the development and validation of analytical methods using high performance liquid chromatography with fluorescence detection (HPLC-FL) and liquid chromatography electrospray ionization tandem mass spectrometry (LC-ESI-MS/MS Q-Tof) for the determination of multi residues of quinolones (enrofloxacin, ciprofloxacin, danofloxacin, sarafloxacin, oxolinic acid and flumequine) in fish; (ii) the development and validation of analytical methods for the determination of oxytetracycline (OTC) in fish feed and tilapia fish fillets using HPLC-DAD and HPLC-FL, respectively, and (iii) the study of tilapias (Oreochromis niloticus) in order to evaluate the depletion of OTC from the fish fillet. In general, the extraction of the quinolones and OTC from the fish matrix was conducted by solid-liquid extraction followed by clean-up on solid phase extraction cartridges. The antimicrobials chromatographic separation was performed on a reverse phase octadecyl hybrid column. The methods were validated through the following parameters: linear range, linearity, sensitivity, selectivity, detection limit, quantitation limit, intra- and inter-assay precision and accuracy. For the LC-MS/MS method, the matrix effect was also evaluated. All methods were adequate to the proposed objectives. In order to evaluate the depletion of OTC in the tilapia fillets, the fish (weight range 93 ¿ 115 g) were given medicated feed in a concentration of 80 mg OTC/kg body weight/day for five consecutive days. The water temperature was between 16.5 to 24.5 °C during the treatment. The depletion curve was fitted to an exponential first order model. The elimination half-life was 2.5 days and the withdrawal period was estimated as five days