Submitted by Sandra Pereira (srpereira@ufrrj.br) on 2017-01-10T11:33:17Z No. of bitstreams: 1 2016 - Fernanda Melo Pereira Taran.pdf: 1274160 bytes, checksum: 1abefb4abb6f8800458c7eb63d22a94c (MD5) / Made available in DSpace on 2017-01-10T11:33:17Z (GMT). No. of bitstreams: 1 2016 - Fernanda Melo Pereira Taran.pdf: 1274160 bytes, checksum: 1abefb4abb6f8800458c7eb63d22a94c (MD5) Previous issue date: 2016-01-06 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior - CAPES / This study aimed to evaluate the in vitro adsorption of fumonisin B1 (FB1) through the use of different strains and concentrations of Saccharomyces cerevisiae in conditions simulating the digestive tract of horses. The experimental design was completely randomized in a factorial 4x5 with four yeast strains (1, 2, 3 and 4) and five concentrations for each strain of 1x107, 5x107, 1x108, 5x108 and 1x109 CFU.mL-1 at pH 2 and 6.8 with three replicates per treatment. In vitro adsorption experiments were carried out in microcentrifuge tubes containing buffered solution mycotoxin and yeast at 39 ? C. The concentration of FB1 was 5 ?g.mL-1. The supernatant of samples containing fumonisin not adsorbed were analyzed and quantified by CLAE. The results of the in vitro adsorption were subjected to a regression analysis based on the S. cerevisiae concentration and yeast strains. It was observed at pH 2 and 6.8 a significant interaction between S. cerevisiae concentration and yeast strain (P <0.001). At pH 2, the the amount of FB1 adsorbed by different yeast strains did not differ with 1x107, 5x107, 1x108 CFU.mL-1, only showed effects for the highest concentrations of 5x108 and 1x109 CFU.mL-1 (P<0.001). At pH 6.8, the differences occurred to concentration of 1x108, 5x108 and 1x109 CFU.mL-1 (P<0.001), but had no effect on lower concentrations (5x107 and 1x107 celulas.mL-1). At the highest concentration of 1x109 CFU.mL-1, strain 4 (SC-47) demonstrated a greater capacity to adsorb FB1, 39.4% and 37.5% at pH 2.0 and 6.8, respectively. In addition, linear responses were observed in the adsorption capacity in all strains evaluated under conditions of acidic and neutral pH. The results demonstrate that the ability of S. cerevisiae to adsorb FB1 is strain-dependent and the pH value may influence the amount of FB1 removed from the solution according to the strain used / Avaliou-se a adsor??o in vitro de fumonisina B1 (FB1) atrav?s do uso de diferentes cepas e concentra??es de Saccharomyces cerevisiae em condi??es que simulam o trato digestivo de equinos. O delineamento experimental foi inteiramente casualizado em esquema fatorial 4x5, com quatro cepas de levedura (1, 2, 3 e 4) e cinco concentra??es para cada cepa de 1x107, 5x107, 1x108, 5x108 e 1x109 UFC.mL-1, sob pH 2 e 6,8 com tr?s repeti??es por tratamento. Os ensaios de adsor??o in vitro foram conduzidos em microtubos contendo solu??o tamponada de micotoxina e levedura a 39 ?C. A concentra??o de FB1 foi de 5 ?g.mL-1. As amostras do sobrenadante contendo as fumonisinas n?o adsorvidas foram analisadas e quantificadas por CLAE. Os resultados foram submetidos ? an?lise de regress?o em fun??o da concentra??o de levedura e cepas de levedura. Observou-se, tanto em pH 2 como a 6,8, intera??o significativa entre concentra??o de FB1 e cepa de levedura (P<0,001). No pH 2, as cepas de levedura n?o diferiram em rela??o a quantidade de FB1 adsorvida nas concentra??es de 1x107, 5x107, 1x108 UFC.mL-1, apenas apresentaram efeito significativo para as concentra??es mais elevadas de 5x108 e 1x109 UFC.mL-1 (P<0,001). Em pH 6,8, as diferen?as ocorreram para as concentra??es de 1x108, 5x108 e 1x109 UFC.mL-1 (P<0,001), n?o apresentando efeito significativo nas concentra??es mais baixas (1x107e 5x107 UFC.mL-1). Na concentra??o mais elevada de 1x109 UFC.mL-1, a cepa 4 (SC-47) demonstrou maior capacidade para adsorver FB1, 39,4% e 37,5% em pH 2,0 e 6,8, respectivamente. Al?m disso, foram observadas respostas lineares na capacidade de adsor??o em todas as cepas avaliadas sob condi??es de pH ?cido e neutro. Os resultados demonstram que a capacidade de adsor??o de FB1 pela S. cerevisiae ? cepa-dependente e que o valor de pH pode influenciar na quantidade de FB1 removida da solu??o de acordo a cepa utilizada.