Made available in DSpace on 2014-06-11T19:28:24Z (GMT). No. of bitstreams: 0 Previous issue date: 2010-06-14Bitstream added on 2014-06-13T20:37:15Z : No. of bitstreams: 1 siloto_ev_me_botfmvz.pdf: 809179 bytes, checksum: 7511ba3985111f498b7461c523562d75 (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / Universidade Estadual Paulista (UNESP) / Os efeitos da aflatoxina e fumonisina e sua associação, sobre a produção e a qualidade dos ovos em poedeiras comerciais, foram avaliados bem como a eficácia de um adsorvente glucano em promover a redução e/ou eliminação total destes efeitos. Foram utilizadas 168 poedeiras com 37 semanas de idade, por um período experimental de 56 dias. O delineamento experimental foi inteiramente casualizado em esquema fatorial 3x2 + 1 (3 tratamentos com micotoxinas: aflatoxina (AF), fumonisina (FU) e aflatoxina + fumonisina (AF + FU); 2 tratamentos com e sem adsorvente; e grupo controle sem micotoxinas e adsorvente), totalizando 7 tratamentos e 6 repetições com 4 aves/gaiola. As rações foram contaminadas, isoladamente ou em combinação, com 1ppm de AF e 25ppm de FU e o adsorvente foi incluído na concentração de 2kg/ton ração. Os tratamentos com presença de AF apresentaram as menores porcentagens (p = 0,0594) de postura (76,72% para AF e 77,38% para AF+FU). A massa de ovos obteve a menor média (p<0,05) no tratamento com AF+FU (49,49 g) que foi diferente do grupo controle (64,06 g). O tratamento com AF apresentou maior espessura e resistência de casca comparado ao grupo controle e ao tratamento com FU. O uso do adsorvente no tratamento com AF reduziu a resistência da casca voltando aos valores próximos aos do controle. As alterações observadas neste estudo são indicativas da toxicidade da aflatoxina na concentração de 1 ppm. Os efeitos da fumonisina foram menos evidentes em função da baixa dose utilizada neste estudo (25mg/kg). O uso de glucano na concentração de 2 kg/ton foi efetivo em reverter alguns dos efeitos tóxicos da aflatoxina e, em menor extensão da fumonisina, quando estas micotoxinas estavam separadamente na ração de poedeiras comerciais / The present study was conducted to evaluate the effects of aflatoxin and fumonisin and their association on production and egg quality in laying hens and was also evaluated the effectiveness of an adsorbent glucan to promote the reduction and/or total elimination of these effects. One hundred and sixty-eight 37-wk-old laying hens were used for a trial period of 56 days. The experimental design was a completely randomized with 3x2+ 1 factorial arrangement (three treatments with mycotoxins: aflatoxin (AF), fumonisin (FU) + fumonisin and aflatoxin (AF + FU), two treatments with and without adsorbent, and the control group without mycotoxin and adsorbent), totaling seven treatments, six replicates and four birds per cage. The mycotoxins were added to rations, singly and in combination, at levels of 1 ppm AF and 25 ppm FU and the adsorbent was included in the dosage of 2kg/ton .The treatments with the presence of AF had the lowest percentages (p = 0,0594) of stance (76,72% to AF and 77,38% to AF + FU). The egg mass received the lowest average (p<0,05) in the treatment with AF + FU (49,49 g) which was different from the control group (64,06 g). Treatment with AF showed higher values of thickness and peel strength compared to the control group and treatment with FU. The use of the adsorbent in the treatment with AF reduced the strength of the shell back to values near baseline. The changes observed in this study are indicative of the toxicity of aflatoxin at a concentration of 1mg/kg. The effects of fumonisin were less evident because of the low levels used in this study (25mg/kg). The level of glucan added to the diets was effective to prevent some of the toxic effects of aflatoxins and to a lesser extent of fumonisin, when the mycotoxins were separately in the diet of laying hens

Esta tese apresenta a obtenção de sílica xerogel a partir de carvão de cascas de arroz e a modificação da sua superfície com um ligante orgânico tipo base de Schiff. O objetivo da utilização deste resíduo agroindustrial é a obtenção de um adsorvente capaz de atuar no tratamento de águas contaminadas contendo íons cádmio II, em uma concepção de valorização de resíduos. A sílica contida na biomassa foi obtida na forma de silicato de sódio através de extração química com solução de hidróxido de sódio, seguida de hidrólise e condensação do monômero através do processo solgel. A modificação da superfície da sílica com o ligante salen foi realizada utilizando o 1,2-dicloroetano como espaçador bifuncional. A sílica xerogel modificada foi avaliada através de análises de isotermas de adsorção e dessorção de nitrogênio (BET/BJH), difração de raios-X (DRX), análise química elementar (CHN), espectroscopia de infravermelho com transformada de Fourier (FTIR), microscopia eletrônica de varredura (MEV) e termogravimetria (TG/DTG). A análise elementar indicou que 0,341 mmol/g de 1,2-dicloroetano e 0,095 mmol/g de salen foi ancorado na superfície da sílica, que apresentou estabilidade térmica até 209°C e área de superfície específica de 106,4 m²/g. Foi realizado um estudo sobre a capacidade de adsorção de íons cádmio (II) pela sílica modificada e não modificada. Os resultados indicam a superior capacidade de adsorção de cádmio pela sílica modificada, em soluções com baixa concentração do íon. / This thesis presents the obtainment of silica xerogel by rice husk charcoal and its surface modification using an organic ligand type Schiff-base. The purpose of this agro-industrial residue utilization is the production of an adsorbent capable to remove heavy metals present in contaminated waters. The silica contained in the biomass was obtained by alkaline extraction in sodium silicate with hydrolysis through sol-gel process, and modified with salen, using 1,2-dichloroethane as bi-functional spacer. The modified xerogel silica was evaluated through analysis of nitrogen adsorption/desorption isotherms (BET/BJH), X-ray diffraction (XRD), chemical elementary analysis (CHN), Fourier transform infrared spectroscopy (FTIR), scanning electronic microscopy (SEM) and thermogravimetric analysis (TG/DTG). The elementary analysis pointed that 0,341mmol/g of the 1,2-dichloroethane and 0,095mmol/g of the salen was anchored to the silica surface, that presented thermal stability until 209°C and specific surface area of 106,4 m²/g. An evaluation about the ion cadmium II adsorption capacity of the silica modified and unmodified was performed. The results pointed to the superior cadmium adsorption capacity for the modified silica if low ion concentration solutions.

Submitted by (edna.saturno@ufrpe.br) on 2017-04-10T13:07:53Z No. of bitstreams: 1 Elainy Cristina Lopes.pdf: 328224 bytes, checksum: 6e351f9ac2697618f1bcab616530817e (MD5) / Made available in DSpace on 2017-04-10T13:07:53Z (GMT). No. of bitstreams: 1 Elainy Cristina Lopes.pdf: 328224 bytes, checksum: 6e351f9ac2697618f1bcab616530817e (MD5) Previous issue date: 2012-07-30 / Conselho Nacional de Pesquisa e Desenvolvimento Científico e Tecnológico - CNPq / Two studies were conducted to evaluate the addition of different types of adsorbents in diets containing corn contaminated by mycotoxins (fumonisins B1 and B2 in 721 and 257 ppb total of 978 ppb and 94.7 ppb in Cyclopiazonic acid). Two experiments were occurring simultaneously, a metabolism and another performance with broilers Ross in a randomized design. These experiments occurred in order to test the effect of three types of adsorbents with the treatments distributed as follows: T1: reference diet with corn considered adequate (control), T2: diet with naturally contaminated maize considered inappropriate, T3, T4 and T5 were more T2 addition of adsorbents A, B and C, respectively. In the diets were analyzed found fumonisins, the total quantities of 125, 509, 677, 589 and 625 ppb for T1, T2, T3, T4 and T5, respectively. In the first study used 180 birds were housed in metabolic cages divided into five treatments and six replicates to evaluate the apparent metabolizable energy and apparent metabolizable energy corrected for nitrogen balance and metabolizability coefficient of dry matter, crude protein and gross energy. No statistical difference was detected for these variables. In the second study we used 360 broiler chicks during the period 1 to 42 days of age housed in pens with wood shavings bedding, distuibuídos in five treatments and six replications with 12 birds per replicate. We evaluated the feed intake, weight gain, feed conversion, carcass weights and percentages, cuts, offal and serum biochemical parameters. The results showed significant differences in feed conversion in the final period. But the amount of mycotoxins present in feed birds offered was not enough for there to be poisoning birds and incurs a significant effect of supplementation of the diets of these animals adsorbents. / Foram realizados dois estudos com o objetivo de avaliar a adição de diferentes tipos de adsorventes em dietas contendo milho contaminado por micotoxinas (fumonisinas B1 e B2 em 721 e 257 ppb totalizando em 978 ppb e ácido ciclopiazônico em 94,7 ppb). Foram dois experimentos que ocorreram simultaneamente, um de metabolismo e o outro de desempenho com frangos de corte da linhagem Ross em delineamento inteiramente casualizado. Estes experimentos ocorreram com a finalidade de testar o efeito dos três tipos de adsorventes sendo os tratamentos distribuídos da seguinte forma: T1: dieta referência com milho considerado adequado (controle); T2: dieta com milho contaminado naturalmente considerado inadequado; T3, T4 e T5 foram T2 mais adição dos adsorventes A, B e C, respectivamente. Nas rações analisadas foram encontradas as fumonisinas, nas quantidades totais de 125, 509, 677, 589 e 625 ppb para os tratamentos T1, T2, T3, T4 e T5, respectivamente. No primeiro estudo foram utilizadas 180 aves alojadas em gaiolas metabólicas divididas em cinco tratamentos e seis repetições, para avaliar a energia metabolizável aparente e a energia metabolizável aparente corrigida pelo balanço de nitrogênio e os coeficientes de metabolizabilidade da matéria seca, proteína bruta e energia bruta. Não foi detectada diferença estatística para estas variáveis. No segundo estudo utilizaram-se 360 pintos de corte no período de 1 a 42 dias de idade alojados em boxes com cama de maravalha, distuibuídos em cinco tratamentos e seis repetições com 12 aves por repetição. Foram avaliados o consumo de ração, ganho de peso, conversão alimentar, pesos e percentagens da carcaça, dos cortes, vísceras e parâmetros bioquímicos séricos. Os resultados mostraram diferenças significativas para a conversão alimentar no período final. Porém a quantidade de micotoxinas presente na ração ofertada as aves não foi suficiente para que houvesse intoxicação das aves e acarretasse um efeito significativo da suplementação dos adsorventes nas dietas destes animais.

O objetivo do presente trabalho foi determinar resíduos de aflatoxinas M1 (AFM1), aflatoxicol (AFL), B1 (AFB1), B2 (AFB2), G1 (AFG1) e G2 (AFG2) não metabolizadas no fígado e rim de frangos de corte, com a finalidade de verificar sua aplicabilidade na avaliação da eficiência de um adsorvente comercial à base de aluminossilicato de cálcio e sódio (HSCAS) incorporado na dieta, bem como determinar o percentual de ligação do adsorvente com a AFB1em ensaios in vitro. Cem frangos de corte (Ross 708), machos, de 1 dia de idade, foram mantidos em baterias metálicas, com acesso ad libitum à ração e água. Utilizou-se um delineamento inteiramente casualizado com 4 tratamentos, sendo cada tratamento composto por 5 gaiolas contendo 5 frangos em cada uma. Os tratamentos foram os seguintes: A) dieta basal (DB), sem adição de HSCAS ou AFB1; B) DB com adição de 0,5% de HSCAS; C) DB com adição de 2,5 mg/kg de AFB1; e D) DB com adição de 2,5 mg/kg de AFB1 e 0,5% de HSCAS. As rações experimentais foram administradas de 1 a 21 dias de vida. No dia 21, 5 frangos de cada tratamento foram insensibilizados com dióxido de carbono, mortos por deslocamento cervical e amostras de fígado e rim foram coletadas para análise de resíduos de AFB1. O HSCAS foi efetivo em se ligar, in vitro, à AFB1, cujos percentuais de ligação variaram de 8,8 a 99,5%, para concentrações do adsorvente entre 0,05 e 100 mg/10 mL. Apesar de o HSCAS ter melhorado, numericamente, o desempenho dos frangos no estudo in vivo, estatisticamente não houve diferença significativa entre os tratamentos C e D. As concentrações de AFB1, AFL, AFG1 e AFB2 foram menores (P&lt;0,05) nos fígados das aves alimentadas com AFB1 adicionado de HSCAS (dieta D), quando comparado com aves alimentadas somente com AFB1 (dieta C). As concentrações de AFB1 também foram menores (P&lt;0,05) nos rins das aves alimentadas com AFB1 adicionado de HSCAS (dieta D) quando comparado com aves alimentadas somente com AFB1 (dieta C). A determinação de resíduos de aflatoxinas no fígado e rins não é aplicável para avaliar a proteção do adsorvente contra efeitos tóxicos das aflatoxinas em frangos de corte, sendo, porém, de grande utilidade para verificar a capacidade do adsorvente em reduzir as concentrações das aflatoxinas residuais nas vísceras de frangos destinadas ao consumo humano. / The objective of the study was to determine residues of aflatoxin M1 (AFM1), aflatoxicol (AFL), B1 (AFB1), B2 (AFB2), G1 (AFG1) and G2 (AFG2) non-metabolized in liver and kidney of broiler chicks, aiming to verify its applicability for evaluation of a commercial adsorbent based-HSCAS efficacy incorporated into the diet, aswell as to determine the binding capacity of a HSCAS for AFB1 in an in vitro testing. One hundred day-old male broilers (Ross 708) were maintained in chick batteries and allowed libitum access to feed and water. A completely randomized design was used with 5 replicate pens of5 chicks assigned to each of 4 dietary treatments from hatch to 21 days. Dietary treatments included: A) basal diet (BD), with no HSCAS or AFB1; B) BD supplemented with 0.5% HSCAS only; C) BD supplemented with 2.5 mg AFB1/kg of feed; and D) BD supplemented with 2.5 mg AFB1/kg of feed and 0.5% HSCAS. On day 21, 5 chicks from each treatment wereinsensibilized with carbon dioxide, killed by cervical dislocation and samples of liverand kidney collected for analysis of AFB1 residues. The HSCAS was effective to binding AFB1 in vitro, with percentage of AFB1 bound varying from 8.8 to 99.5% for adsorbent concentrations between 0.05 and 100 mg/10mL. Although HSCAS has improved numerically the performance of broilers on the in vivostudy, there was no statistically significant difference between treatments C and D. Concentrations of AFB1, AFL, AFG1 and AFB2 were lower (P&lt;0.05) in livers of birds fed AFB1 plus HSCAS (diet D), when compared to birds fed AFB1 alone (diet C). Concentrations of AFB1 were also lower (P&lt;0.05) in kidneys of birds fed AFB1 plus HSCAS (diet D) compared to those fed AFB1 only (diet C). The determination of aflatoxin residues in liver and kidney is not applicable for evaluation of the adsorbent protection against the toxic effects of aflatoxins in broiler chicks, being, however, very useful to verify the adsorbentcapacity to reduce the concentration of aflatoxin residues in the organs of chickens intended for human consumption.

Submitted by Rosangela Silva (rosangela.silva3@unioeste.br) on 2017-09-01T20:08:13Z No. of bitstreams: 2 Lara Talita Schnider.pdf: 2363196 bytes, checksum: a42ab4a15a037ec5a51b66bd1f354f33 (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) / Made available in DSpace on 2017-09-01T20:08:13Z (GMT). No. of bitstreams: 2 Lara Talita Schnider.pdf: 2363196 bytes, checksum: a42ab4a15a037ec5a51b66bd1f354f33 (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Previous issue date: 2017-02-17 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / The development of technologies that reuse wastes from the agricultural, industrial and urban activities is essential, mainly at the environmental point of view, since high amounts of toxic materials and pollutants are incorrectly disposed on the environment, practice that tends to grow concurrently with the industrial expansion. The waste cooking oil is generated in large volumes in urban centers due to the high consumption of refined oils in food cooking. This is considered as a potential alternative feedstock for biodiesel synthesis, one of the country’s mainly used biofuels. However, the low and inconstant quality of this residual feedstock is one of the barriers for its use at homogeneous alkaline transesterification, route commonly used in the biodiesel production thus requiring pretreatment steps of the waste cooking oil before this process. In this context, the objective of this work was the treatment of waste cooking oil by adsorption process, using the in natura rice husk, biomass from agricultural sector, and actived carbon as adsorbent materials. From an experimental planning of the rotational central composite design, it was searched the best experimental conditions for the waste cooking oil treatment in relation to the temperature, adsorbent mass and agitation speed, thus evaluating the influence of these operational parameters on the reduction of the acidity value and peroxide value, and aiming the simultaneous maximization of analyzed variables at the intervals tested. Using the activated carbon (commercial adsorbent) average reductions of acidity and peroxides of 47 and 29 %, respectively. Observed using the rice husk, the reductions was 40 and 24 % for acidity and peroxides, respectively. In order to minimize process costs, in addition to the use of residual materials, the use of rice husk as an alternative adsorbent in the residual treatment is advantageous, since it is a low cost material, available on a large scale and gave results close to those obtained with the activated carbon. / O desenvolvimento de tecnologias que reaproveitem resíduos oriundos das atividades agrícolas, industriais e urbanas é essencial, principalmente do ponto de vista ambiental, uma vez que elevadas quantidades de materiais tóxicos e poluentes são dispostos de maneira incorreta no meio ambiente, prática que tende a crescer concomitantemente à expansão industrial. O óleo residual é gerado em grandes volumes nos centros urbanos em virtude do elevado consumo de óleo refinado na cocção de alimentos. Este é considerado como uma alternativa promissora de matéria-prima para a síntese de biodiesel, um dos principais biocombustíveis do país. Porém, a baixa e inconstante qualidade deste resíduo é um dos entraves para sua utilização na transesterificação homogênea alcalina, rota comumente empregada na produção de biodiesel, fazendo-se necessário a aplicação de pré-tratamento do óleo residual. Neste contexto, o objetivo deste trabalho foi o tratamento de óleo residual por meio do processo de adsorção, empregando a casca de arroz in natura, biomassa advinda do setor agrícola, e o carvão ativado como materiais adsorventes. A partir de um planejamento experimental do tipo delineamento composto central rotacional, buscaram-se as melhores condições experimentais para o tratamento do óleo residual em relação à temperatura, massa de adsorvente e agitação, avaliando a influência desses parâmetros operacionais na redução do índice de acidez e índice de peróxido, objetivando a maximização simultânea das variáveis respostas analisadas, nos intervalos testados. Utilizando o carvão ativado (adsorvente comercial) atingiram-se reduções médias de acidez e peróxidos de 47 e 29 %, respectivamente. Já nos tratamentos com o emprego da casca de arroz, as reduções foram de 40 e 24 % para acidez e peróxidos, respectivamente. Tendo em vista a minimização de custos do processo, além do aproveitamento de materiais de cunho residual, a utilização da casca de arroz como adsorvente alternativo no tratamento residual mostra-se vantajosa, uma vez que é um material de baixo custo, disponível em larga escala e que proporcionou resultados próximos aos obtidos com o carvão ativado.

Made available in DSpace on 2014-08-20T14:38:43Z (GMT). No. of bitstreams: 1 Dissertacao_Lorena_Lacava_Lopes.pdf: 962849 bytes, checksum: 4c8404df3636ba5dbe748e4c8b688430 (MD5) Previous issue date: 2011-02-28 / This study aimed to investigate the use of sterified glucomannan adsorbent on the productive performance of broilers of broilers fed mouldy corn.. A total of 1440 dayold broilers were allocated in pens, ten replications per treatment. Treatments were: T1 non-mouldy corn, without adsorbent (control); T2- non-mouldy corn with adsorbent; T3- mouldy corn without adsorbent and T4- mouldy corn with adsorbent. Weekly, birds and diets were evaluated for weight gain, feed intake, feed conversion, viability and efficiency factor. No significant interaction between corn and adsorbent was observed. Mouldy corn brought about a decrease in feed consumption, feed efficiency and viability. However, birds fed mycotoxin adsorbent showed better feed efficiency, viability and efficiency factor. These results indicate that the use of mouldy corn in broilers diets has negative effects on performance and the addition of absorbent improves feed conversion, efficiency factor and viability of the birds. / Objetivou-se avaliar os efeitos de um adsorvente à base de glucomanano esterificado, em dietas contendo milho naturalmente fungado para frangos de corte, sobre o desempenho zootécnico. O estudo foi realizado durante 42 dias experimentais, utilizando-se 1440 frangos de corte com um dia de idade. Os animais foram submetidos a quatro tratamentos, com 10 repetições cada, sendo: T1 ração com milho com baixa contaminação, sem adsorvente (controle); T2 ração com milho com baixa contaminação, com adsorvente; T3 ração com milho com alta contaminação, sem adsorvente e T4 ração milho com alta contaminação, com adsorvente. As aves e a ração foram pesadas semanalmente para a avaliação do ganho de peso corporal, consumo de ração, conversão alimentar, viabilidade e índice de eficiência produtiva. Não houve interação significativa entre os fatores milho e adsorvente. As aves que receberam dietas contendo milho fungado tiveram uma redução significativa no consumo de ração e na viabilidade e piora na conversão alimentar. Em contrapartida, as aves que receberam dietas contendo adsorvente, apresentaram melhora na conversão alimentar, viabilidade e índice de eficiência produtiva. Conclui-se que a utilização de milho fungado na dieta de frangos de corte afeta negativamente o desempenho dos animais, sendo que o uso de adsorvente nestas dietas melhora a conversão alimentar, índice de eficiência produtiva e a viabilidade das aves.

Conselho Nacional de Desenvolvimento Científico e Tecnológico / The objective of this dissertation was to evaluate the impacts of aflatoxin in a concentration of 2,8mg/kg, and sodic montmorillonite on performance, enzyme activity and liver function in broilers from 1 to 21 days, as well as compare to other products already on the market. Were utilize 540 chickens housed in cages. Experimental design was completely randomized, with 9 treatments and 6 replications. The treatments were: Control (basal diet), Ads0,50 (basal diet + 0,50% Test adsorbent), Afla (basal diet + 2,8mg/kg of Aflatoxin), Ads0,25 + Afla (basal diet + 0,25% Test adsorbent + 2,8mg/kg of Aflatoxin), Ads0,50 + Afla (basal diet + 0,50% Test adsorbent + 2,8mg/kg of Aflatoxin), AdsA + Afla (basal diet + 0,50% A adsorbent + 2,8mg/kg of Aflatoxin), AdsB + Afla(basal diet + 0,50% B adsorbent + 2,8mg/kg of Aflatoxin), AdsC + Afla (basal diet + 0,50% C adsorbent + 2,8mg/kg of Aflatoxin), AdsD + Afla (basal diet + 0,50% D adsorbent + 2,8mg/kg of Aflatoxin). The adsorbents A, B, C, D are based sodic montmorillonite, but come from different companies. The data collected were subjected to analysis of variance and comparison of means by Tukey test (P ≤ 0.05). It is concluded that the test adsorbent in a concentration of 0,50% was effectively promoted and a reduction of toxic effects of aflatoxin on performance of broilers at 21 days of age but did not avoided changes in liver function and liver enzymes. And gave results similar to the products C and D, and higher than product B. / O objetivo desta dissertação foi avaliar os impactos da aflatoxina, na concentração de 2,8mg/kg, e da montmorilonita sódica sobre o desempenho, atividade enzimática e função do fígado em frangos de corte de 1 aos 21 dias, bem como comparar o produto à outros já existentes no mercado. Foram utilizados 540 frangos, alojados em baterias metálicas. O delineamento experimental foi inteiramente casualizado, composto por 9 tratamentos e 6 repetições. Os tratamentos utilizados foram: Controle (dieta basal), Ads0,50 (dieta basal + 0,50% adsorvente Teste), Afla (dieta basal + 2,8mg/kg de aflatoxina), Ads0,25+Afla (dieta basal + 0,25% adsorvente Teste + 2,8mg/kg de aflatoxina), Ads0,50+Afla (dieta basal + 0,50% adsorvente Teste + 2,8mg/kg de aflatoxina), AdsA+Afla (dieta basal + 0,50% adsorvente A + 2,8mg/kg de aflatoxina), AdsB+Afla (dieta basal + 0,50% adsorvente B + 2,8mg/kg de aflatoxina), AdsC+Afla (dieta basal + 0,50% adsorvente C + 2,8mg/kg de aflatoxina), AdsD + Afla (dieta basal + 0,50% adsorvente D + 2,8mg/kg de aflatoxina). Os adsorventes A, B, C, D são à base de montmorilonita sódica, porém oriundos de diferentes empresas. Os dados coletados foram submetidos à análise de variância, e a comparação entre médias pelo teste de Tukey (P≤0,05). Conclui-se que o adsorvente Teste na concentração de 0,50% foi eficaz e promoveu uma redução dos efeitos tóxicos da aflatoxina sobre o desempenho zootécnico de frangos de corte aos 21 dias de idade, porém não evitou alterações nas enzimas e função hepática. E ainda, apresentou resultados semelhantes aos produtos C e D, e superior ao produto B.

Alkaloid toxicities negatively impact livestock health and production and are of serious economic concern to animal industries. To date, few strategies have been developed to evaluate alkaloid levels in feed or to counteract alkaloid toxicities. The present research evaluated the applicability of imprinting technology to synthesize polymers that have potential to interact with ergot alkaloids and therefore reduce their bioavailability in the GIT. The studies also evaluated applicability of synthesized polymers for use in the ruminal environment using an in vitro ruminal fermentation model, and for the ability to ameliorate vasoconstriction using ex vivo myographic evaluations. In the first experiment, styrene-based molecularly imprinted polymer (MIP) was synthesized using ergotamine as the imprinting template and evaluated for specificity of adsorption to various ergot alkaloids. Cross reactivity with related alkaloids exists due to similarities in structure and functional groups. Both polymers (MIP and NIP) showed strong adsorption intensity and no difference was observed for estimated maximum adsorption capacity between MIP and NIP. Morphologically, MIP was highly porous with greater surface area than NIP. Solid phase extraction indicated stronger adsorption of MIP than NIP to ergot alkaloids suggesting the potential for MIP as a sorbent material for solid phase extraction (SPE) columns used for sample clean-up prior to HPLC or LC-MS/MS analysis of complex samples. In Experiment 2, methacrylic acid-based polymers were synthesized with ergotamine as a template. Among the 4 alkaloids evaluated for selectivity, adsorption difference between MIP and NIP interacted with alkaloid concentration, although differences were generally consistent across concentrations. Imprinting did not affect lysergol and bromocriptine adsorption, but resulted in higher adsorption to methylergonovine. However, there was no difference between MIP and NIP for adsorption of ergotamine. Hydrophobic interactions and H-bonding were the primary interactive forces between polymers and alkaloid adsorbents. Morphologically, MIP had greater surface area and porosity implying a larger surface for adsorption. In addition to its application as SPE sorbent, this MIP was a suitable candidate for application as a feed adsorbent to reduce the bioavailability of certain alkaloid in the gut. In experiment 3, methacrylic acid-based polymers were evaluated for their effect on in vitro ruminal fermentation. There were no interactions between polymer type and inclusion level, and no differences between polymer types for cumulative gas production or rate of gas production. Total gas production and rate of gas production were unaffected by inclusion level. Polymers did not affect total or individual VFA concentrations, ammonia-N or methane concentration at any inclusion level. However, a logarithmic increase in polymer dose level decreased the pH linearly with maximum depression of 0.24 units. This study indicated that, within the range of expected use levels, polymers were essentially inert and would not be expected to affect ruminal fermentation. In experiment 4, ex vivo myographic bioassays were used to determine the impact of polymers on ergotamine bioavailability. Responses measured in the ex vivo myographic studies had similar trend as the responses generated from in vitro isothermal adsorption studies. Results of that study also showed that ex vivo myographic responses could be predicted from in vitro isothermal adsorption studies with more than 80% accuracy. These studies indicate that synthetic polymers are potentially effective adsorbents to mitigate ergot toxicity with little evidence of substantial differences between MIP and NIP.

M. Tech (Department of Chemistry, Faculty of Applied and Computer Sciences) Vaal University of Technology. / Persisting challenges associated with remediation of heavy metals from aqueous media have stirred the need for enhancement of current technologies. Cellulosic agro waste materials (AWM) as well as ion-imprinted polymers (IIP) have received ardent attention from researchers. These materials are often employed in the following industries: water and wastewater treatment, medical, pharmaceutical and packaging. Applications in water and wastewater treatment have gained significant interest due to desirable features they possess. In the case of AWM, these features include a tuneable surface area and poor porosity, basic surface functional groups and chemical stability. Some desired features in IIP include adsorption sites compatible for the ion imprint obtained after leaching with suitable reagents, rigidity and reusability. The efficacy of employing AWM and IIP for the remediation of toxic chromium from aqueous solution was explored. The current study is made up of part A and B. In part A, Macadamia nutshell powder was treated using HNO3, NaOH, as well as Fenton’s reagent. The three materials underwent a new modification which involved reacting treated adsorbents with cetyltrimethylammonium chloride (CTAC), followed by immobilization of 1,5' diphenylcarbazide (DPC) ligand. The adsorbents were ultimately washed, dried and stored for Cr(VI) batch adsorption experiments. Part B involved a synthesis of IIP and their non-imprinted polymer counterpart (NIP) for Cr(VI) sequestration in aqueous solution. This was done by precipitation polymerization of functional monomers, crosslinker and DPC-Cr(VI) complex as a template. Non-imprinted polymers were fashioned in a manner like that of IIP but with the exclusion of Cr(VI) ion template. Characterizations of the adsorbents were done using Fourier transform infrared spectroscopy (FTIR), thermogravimetric analysis (TGA), scanning electron microscopy (SEM), X-ray fluorescence (XRF), and carbon, hydrogen, nitrogen and sulphur (CHNS) analyzer. Batch adsorption experiments were done and parameters such as solution pH, adsorbent dosage, initial Cr(VI) concentration and contact time were optimized. Working solutions were analyzed using ultraviolet-visible (UV-Vis) and atomic absorption (AA) spectroscopy. Adsorption parameters found to be optimum for DPC immobilized cellulosic adsorbents were pH 1.4, adsorbent mass of 0.1 g, 100 mg/L initial concentration and 125 minutes of contact time. The adsorption parameters determined to be optimum for IIP and NIP were pH 2.6, 0.2 g adsorbent mass, 80 mg/L initial concentration and 240 minutes of contact time. Reusability studies demonstrated the potential of adsorbents to remove Cr(VI) ions from aqueous media after successive adsorption-desorption cycles. Selectivity studies indicated that DPC immobilized adsorbents as well as IIP were able to selectively adsorb Cr(VI) ions from aqueous media in the presence of Zn(II), Cu(II), Co(II) and NI(II) ions. Kinetic models revealed that DPC immobilized cellulosic adsorbents and synthetic IIP were most fitting for pseudo-second order and pseudo first order, respectively. On the other hand, adsorption isotherm studies demonstrated that DPC immobilized cellulosic adsorbents and synthetic polymers were best fit for Freundlich and Langmuir adsorption isotherm, respectively.

京都大学 / 新制・課程博士 / 博士(工学) / 甲第23181号 / 工博第4825号 / 新制||工||1754(附属図書館) / 京都大学大学院工学研究科都市環境工学専攻 / (主査)教授 高岡 昌輝, 教授 橋本 訓, 准教授 大下 和徹 / 学位規則第4条第1項該当 / Doctor of Philosophy (Engineering) / Kyoto University / DFAM