Thèse de doctorat : Sciences et techniques de l'environnement : Paris 12 : 2005. / Version électronique uniquement consultable au sein de l'Université Paris 12 (Intranet). Titre provenant de l'écran-titre. Bibliogr. : 227 réf.

Aflatoxin is a carcinogenic mycotoxin. Aflatoxin contamination of susceptible crops is the product of communities of Aspergillus section Flavi and average aflatoxin-producing potential of these communities influence aflatoxin contamination risk. In 2004 and 2005, Sugarcane producing counties in the Rio Grande Valley of Texas (RGV) had unique aflatoxin-producing communities containing Aspergillus parasiticus. Sugarcane fields or those rotated for less than two years had Aspergillus section Flavi communities dominated by A. parasiticus. A. parasiticus was rarely detected in long-term rotation fields and not detected in counties without sugarcane crops. Aflatoxin-producing fungi infecting RGV sugarcane stems ranged from 52 - 95% A. parasiticus in hand-collected samples and billets for commercial planting, respectively. Identical A. parasiticus fungi found in Japan caused aflatoxin contamination of raw sugar there. Population genetics and phylogenetics were used to characterize a global sampling of 112 A. parasiticus and identify geographic distributions and crop associations within the species. One population shows clear association with sugarcane and is distributed to Asia, Africa and North America, implicating human involvement in its distribution. A. parasiticus populations from maize and peanut have broad geographic distribution but crop specific lineages and/or populations were not detected. One A. parasiticus population isolated from maize has a distribution limited to Mexico. A phylogeny generated from a partial nitrate reductase gene resolves a lineage that correlates with the sugarcane population and suggests crop association and geographic distribution may drive divergence within A. parasiticus. Crop associations shape fungal communities and must be considered for aflatoxin management. Native food enthusiasts in Arizona conduct public millings of wild- and landscape-collected mesquite pods (Prosopis spp.) to produce mesquite flour, which is often consumed in the same localities where it is produced without conventional food safety inspection. Aflatoxin was found in imported, domestic, and non-commercial mesquite flour batches, with 10% above the FDA action level for human food (>20 ppb), and 95% could not be exported to Europe (>2 ppb). Aflatoxin content in Tucson was largely explained (63%) by harvest date with those harvested later yielding more aflatoxin. Lateral flow aflatoxin assay of mesquite flour proved viable for lab and public testing.

The combined effect of Modified Atmosphere Packaging (MAP) involving gas packaging, oxygen absorbent and other environmental factors to control aflatoxin production by Aspergillus flavus and Aspergillus parasiticus in both synthetic media and peanuts were studied using a process optimization technique termed Response Surface Methodology (RSM). Regression analysis of the data indicated that water activity (a$ sb{ rm w}$), pH, storage temperature, initial concentration of headspace oxygen and inoculum level were all highly significant factors (p 0%). These changes in the barrier characteristics influenced the headspace gas composition within the product and under modified atmospheres hence the level of aflatoxin detected in these stored products. / In conclusion, this study has shown that the combined effect of several "barriers" can be used in conjunction with low oxygen modified atmosphere and high barrier packaging films to inhibit or reduce aflatoxin to safe and acceptable levels, particularly at abusive temperatures encountered during storage.

Thesis (M.Sc. (Biochemistry))--Mahidol Uninversity, 1978.

Micotoxinas são metabólitos secundários produzidos por fungos filamentosos que podem contaminar os grãos em diferentes períodos de pré e pós-colheita. O objetivo desse trabalho foi avaliar a contaminação fúngica e por micotoxinas em diferentes períodos do cultivo do amendoim no Rio Grande o Sul, considerando diferentes regiões e cultivares, durante as safras 2006/2007 e 2007/2008 e, ainda, desenvolver um método eficiente de quantificação de aflatoxina B1, baseado na cromatografia em camada delgada com detector de carga acoplada. Foram coletadas nas regiões de Augusto Pestana e Ivorá, amostras dos cultivares Tatu e Paraguaio, em diferentes períodos da cultura: (1) solo pré-plantio, (2) enchimento dos grãos, (3) colheita, (4) pós-secagem e (5) solo pós-colheita. Os fungos contaminantes do solo foram quantificados pela técnica de diluição seriada e nos grãos, o percentual de incidência foi determinado pela técnica de plaqueamento direto. O potencial toxigênico de Aspergillus seção Flavi e Aspergillus seção Nigri foi verificado em Agar Coco e Agar Extrato de Levedura Sacarose, respectivamente. Aflatoxina B1 e ocratoxina A foram determinadas por cromatografia em camada delgada com detector de carga acoplada. As espécies predominantes em todas as amostras foram Aspergillus flavus e Aspergillus niger var. niger. Entre as espécies de A. flavus e A. parasiticus, 89,3% e 39,2%, se mostraram produtoras de aflatoxina B1, respectivamente. Nenhum dos isolados de A. niger var. niger produziu ocratoxina nas condições testadas. Aflatoxina B1 foi detectada em 50% das amostras, com níveis entre 16 μg/Kg e 115 μg/Kg. Ocratoxina A foi detectada em 25% das amostras, com níveis entre 12,2 μg/Kg e 76,9 μg/Kg. Foi observada a ocorrência simultânea das duas micotoxinas em amostras do período pós-colheita. O método desenvolvido para quantificação de aflatoxina B1, baseado em procedimentos de fotometria fotográfica, se mostrou sensível, eficiente e prático, apresentando um limite de detecção de 0,4 ng por mancha, um limite de quantificação de 1,2 μg/kg e média de recuperação de 92%. / Mycotoxins are secondary metabolites produce by filamentous fungi that can contaminate grains in different stages of pre and postharvest management. The objective of this study was to investigate the occurrence of fungi and mycotoxins at different maturation stages of peanut produced in different regions of south of Brazil during 2006/2007 and 2007/2008 harvests. Moreover, to develop an efficient quantification method of aflatoxin B1, based on thin-layer chromatography and charged coupled device detector. Peanut samples, Tatu and Paraguaio varieties, were obtained in regions of Augusto Pestana and Ivorá, in different stages of cultura: (1) soil before planting, (2) pod filling, (3) at harvest, (4) after drying, (5) soil after harvest. The soil contamination was quantified by serial dilution technique and the fungi incidence on grains was determinate by direct planting technique. The toxigenic potential of Aspergillus section Flavi and Aspergillus section Nigri was verified in Coco Medium Ágar and Yeast Extract Sucrose agar medium, respectively. Aflatoxin B1 and ochratoxin A were determinate by on thin-layer chromatography and charged coupled device detector. The predominant species in all samples were Aspergillus flavus and Aspergillus niger var. niger. Among the species of A. flavus and A. parasiticus, 89,3% e 39,2%, produced aflatoxin B1, respectively. None of A. section Nigri isolates were ochratoxin A producers in the conditions tested. Aflatoxin B1 was detected in 50% of samples, with levels of 16.0 μg/Kg to 115.0 μg/Kg. Ochratoxin A was detected in 25% of samples, with levels of 12.2 μg/Kg to 76.9 μg/Kg. It was observed the co-occurrence of both mycotoxins in samples of postharvest. The method developed for aflatoxin B1 quantification was sensitive, efficient and practical, with a detection limit of 0.4 ng per spot, a limit of quantification of 1.2 μg/kg and average recovery of 92%.

The relationship between a pathogen and its host is a complex series of events that occurs at the molecular level and is controlled by transcriptional and protein interactions. To facilitate the understanding of these mechanisms in Aspergillus flavus and Zea mays, three approaches were taken: 1) the development of a predicted interactome for Z. mays (PiZeaM), 2) the development of co-expression networks for Z. mays and A. flavus from RNA-seq data, and 3) the development of causal inference networks depicting interactions between the host and the pathogen. PiZeaM is the genome-wide roadmap of protein-protein interactions that occur within Z. mays. PiZeaM helps create a novel map of the interactions in Z. mays in response to biotic and abiotic stresses. To further support the predicted interactions, an analysis of microarray-based gene expression was used to produce a gene co-expression network. PiZeaM was able to capture conserved resistance pathways involved involved in the response to pathogens, abiotic stress and development. Gene Co-expression networks were developed by the simultaneous use of correlations to develop networks for differentially expressed genes, resistance marker genes, pathogenicity genes, and genes involved is secondary metabolism in Z. mays and A. flavus. From these networks, correlation and anti-correlation of host and pathogen gene expression was detected, revealing genes that potentially interact at different stages of pathogenesis. Finally, causal gene regulatory relationships were inferred using partial correlation analysis of Z. mays infected with A. flavus over a 3 day period. The gene regulatory network (GRN) sheds light on the specifics of the mechanisms of pathogenesis and resistance that govern the Z. mays-A. flavus interaction. The direct product of this research is the understanding of key transcription factors and signaling genes involved in resistance. This body of research highlights how PPIs and GRNs can be utilized to identify biomarkers and gene functions in both Z. mays and A. flavus.

Made available in DSpace on 2015-09-17T15:24:54Z (GMT). No. of bitstreams: 0 Previous issue date: 2015. Added 1 bitstream(s) on 2015-09-17T15:47:03Z : No. of bitstreams: 1 000844265_20160216.pdf: 1037286 bytes, checksum: 2d34cb446cc67885f158101473477c9d (MD5) Bitstreams deleted on 2016-02-18T10:00:23Z: 000844265_20160216.pdf,. Added 1 bitstream(s) on 2016-02-18T10:01:05Z : No. of bitstreams: 1 000844265.pdf: 1992846 bytes, checksum: e982fa28a44e80071f8508bc440c112d (MD5) / Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) / O presente trabalho descreve a síntese, caracterização e estudo das propriedades antimicrobianas de derivados anfifílicos de quitosana contra o fungo Aspergillus flavus. A quitosana utilizada nas sínteses foi obtida a partir da reação de desacetilação heterogênea de quitosana comercial. O grau médio de desacetilação foi determinado por Ressonância Magnética Nuclear de Hidrogênio, cujo resultado foi de 97,3%. As massas moleculares das quitosanas comercial e desacetilada foram determinadas por cromatografia de permeação em gel e os resultados obtidos foram 338,46 kDa e 137,12 kDa, respectivamente. Os derivados anfifílicos foram sintetizados em um processo de duas etapas: inicialmente realizou-se a alquilação da quitosana desacetilada pela inserção de uma proporção fixa de grupos dodecila (4%) na cadeia polimérica com posterior redução da base de Schiff empregando-se borocianohidreto de sódio. Em seguida foram inseridas proporções crescentes do grupo quaternário pentiltrimetilamônio. Os graus de substituição com grupos dodecila (GSDD) e grupos pentiltrimetilamônio (GDPE) foram determinados por RMN de 1H. O GSDD obtido foi de 4,0%, enquanto que os GDPE foram de 4,8; 12,7 e 46,3%. Todos os derivados sintetizados foram testados in vitro contra o fungo Aspergillus flavus em concentrações crescentes. Os ensaios microbiológicos mostraram que os derivados modificados com grupos dodecila e pentiltrimetilamônio são mais eficientes em inibir o crescimento do fungo Aspergillus flavus quando comparado à quitosana desacetilada e que a presença de grupos hidrofóbicos na cadeia do polímero proporciona uma interação mais forte com a membrana celular. Os resultados dos estudos utilizando modelos de membranas corroboraram com os dos ensaios microbiológicos, evidenciando que a presença de grupos dodecila na cadeia da quitosana aumenta a interação com as vesículas, resultando em... / In this work is described the synthesis, characterization and study of antimicrobial properties of amphiphilic derivatives of chitosan against Aspergillus flavus. Deacetylated chitosan was obtained from the heterogeneous deacetylation of the commercial chitosan. The degree of deacetylation was determined by Hydrogen Nuclear Magnetic Resonance and the result was 97.3%. Molecular weights of commercial and deacetylated chitosans were determined by gel permeation chromatography and the obtained values were 338.46 kDa and 137.12 kDa, respectively. The hydrophobic derivatives were synthesized by a reductive amination reaction with dodecylaldehyde followed by reduction with sodium cyanoborohydride. Next increasing proportions of the quaternary group pentyltrimethylammonium was inserted on hydrophobic derivative. The degrees of substitution by dodecyl (4.0%) and pentyltrimethylammonium groups (4.8, 12.7 and 46.3%) were determined by Hydrogen Nuclear Magnetic Resonance. All synthesized derivatives were tested in vitro against Aspergillus flavus at increasing concentrations. The results showed that the modified derivatives with pentyltrimethylamonnium and dodecyl groups are more effective in inhibiting the growth of the fungus Aspergillus flavus when compared to deacetylated chitosan and the presence of hydrophobic groups in the polymer chain provides a stronger interaction with the cell membrane. The results of studies with model membranes agreed with the results of microbiological tests, showing that the presence of hydrophobic groups in chitosan backbone increases the interaction with lipid vesicles resulting in an increase in vesicles diameter and zeta potential. At first, it can be postulated that the mechanism of chitosan action against fungi is favored by hydrophobic interactions between chitosan derivatives and membrane lipids and may involve the adsorption on the cell wall and cell membrane disruption...

Micotoxinas são metabólitos secundários produzidos por fungos filamentosos que podem contaminar os grãos em diferentes períodos de pré e pós-colheita. O objetivo desse trabalho foi avaliar a contaminação fúngica e por micotoxinas em diferentes períodos do cultivo do amendoim no Rio Grande o Sul, considerando diferentes regiões e cultivares, durante as safras 2006/2007 e 2007/2008 e, ainda, desenvolver um método eficiente de quantificação de aflatoxina B1, baseado na cromatografia em camada delgada com detector de carga acoplada. Foram coletadas nas regiões de Augusto Pestana e Ivorá, amostras dos cultivares Tatu e Paraguaio, em diferentes períodos da cultura: (1) solo pré-plantio, (2) enchimento dos grãos, (3) colheita, (4) pós-secagem e (5) solo pós-colheita. Os fungos contaminantes do solo foram quantificados pela técnica de diluição seriada e nos grãos, o percentual de incidência foi determinado pela técnica de plaqueamento direto. O potencial toxigênico de Aspergillus seção Flavi e Aspergillus seção Nigri foi verificado em Agar Coco e Agar Extrato de Levedura Sacarose, respectivamente. Aflatoxina B1 e ocratoxina A foram determinadas por cromatografia em camada delgada com detector de carga acoplada. As espécies predominantes em todas as amostras foram Aspergillus flavus e Aspergillus niger var. niger. Entre as espécies de A. flavus e A. parasiticus, 89,3% e 39,2%, se mostraram produtoras de aflatoxina B1, respectivamente. Nenhum dos isolados de A. niger var. niger produziu ocratoxina nas condições testadas. Aflatoxina B1 foi detectada em 50% das amostras, com níveis entre 16 μg/Kg e 115 μg/Kg. Ocratoxina A foi detectada em 25% das amostras, com níveis entre 12,2 μg/Kg e 76,9 μg/Kg. Foi observada a ocorrência simultânea das duas micotoxinas em amostras do período pós-colheita. O método desenvolvido para quantificação de aflatoxina B1, baseado em procedimentos de fotometria fotográfica, se mostrou sensível, eficiente e prático, apresentando um limite de detecção de 0,4 ng por mancha, um limite de quantificação de 1,2 μg/kg e média de recuperação de 92%. / Mycotoxins are secondary metabolites produce by filamentous fungi that can contaminate grains in different stages of pre and postharvest management. The objective of this study was to investigate the occurrence of fungi and mycotoxins at different maturation stages of peanut produced in different regions of south of Brazil during 2006/2007 and 2007/2008 harvests. Moreover, to develop an efficient quantification method of aflatoxin B1, based on thin-layer chromatography and charged coupled device detector. Peanut samples, Tatu and Paraguaio varieties, were obtained in regions of Augusto Pestana and Ivorá, in different stages of cultura: (1) soil before planting, (2) pod filling, (3) at harvest, (4) after drying, (5) soil after harvest. The soil contamination was quantified by serial dilution technique and the fungi incidence on grains was determinate by direct planting technique. The toxigenic potential of Aspergillus section Flavi and Aspergillus section Nigri was verified in Coco Medium Ágar and Yeast Extract Sucrose agar medium, respectively. Aflatoxin B1 and ochratoxin A were determinate by on thin-layer chromatography and charged coupled device detector. The predominant species in all samples were Aspergillus flavus and Aspergillus niger var. niger. Among the species of A. flavus and A. parasiticus, 89,3% e 39,2%, produced aflatoxin B1, respectively. None of A. section Nigri isolates were ochratoxin A producers in the conditions tested. Aflatoxin B1 was detected in 50% of samples, with levels of 16.0 μg/Kg to 115.0 μg/Kg. Ochratoxin A was detected in 25% of samples, with levels of 12.2 μg/Kg to 76.9 μg/Kg. It was observed the co-occurrence of both mycotoxins in samples of postharvest. The method developed for aflatoxin B1 quantification was sensitive, efficient and practical, with a detection limit of 0.4 ng per spot, a limit of quantification of 1.2 μg/kg and average recovery of 92%.

Micotoxinas são metabólitos secundários produzidos por fungos filamentosos que podem contaminar os grãos em diferentes períodos de pré e pós-colheita. O objetivo desse trabalho foi avaliar a contaminação fúngica e por micotoxinas em diferentes períodos do cultivo do amendoim no Rio Grande o Sul, considerando diferentes regiões e cultivares, durante as safras 2006/2007 e 2007/2008 e, ainda, desenvolver um método eficiente de quantificação de aflatoxina B1, baseado na cromatografia em camada delgada com detector de carga acoplada. Foram coletadas nas regiões de Augusto Pestana e Ivorá, amostras dos cultivares Tatu e Paraguaio, em diferentes períodos da cultura: (1) solo pré-plantio, (2) enchimento dos grãos, (3) colheita, (4) pós-secagem e (5) solo pós-colheita. Os fungos contaminantes do solo foram quantificados pela técnica de diluição seriada e nos grãos, o percentual de incidência foi determinado pela técnica de plaqueamento direto. O potencial toxigênico de Aspergillus seção Flavi e Aspergillus seção Nigri foi verificado em Agar Coco e Agar Extrato de Levedura Sacarose, respectivamente. Aflatoxina B1 e ocratoxina A foram determinadas por cromatografia em camada delgada com detector de carga acoplada. As espécies predominantes em todas as amostras foram Aspergillus flavus e Aspergillus niger var. niger. Entre as espécies de A. flavus e A. parasiticus, 89,3% e 39,2%, se mostraram produtoras de aflatoxina B1, respectivamente. Nenhum dos isolados de A. niger var. niger produziu ocratoxina nas condições testadas. Aflatoxina B1 foi detectada em 50% das amostras, com níveis entre 16 μg/Kg e 115 μg/Kg. Ocratoxina A foi detectada em 25% das amostras, com níveis entre 12,2 μg/Kg e 76,9 μg/Kg. Foi observada a ocorrência simultânea das duas micotoxinas em amostras do período pós-colheita. O método desenvolvido para quantificação de aflatoxina B1, baseado em procedimentos de fotometria fotográfica, se mostrou sensível, eficiente e prático, apresentando um limite de detecção de 0,4 ng por mancha, um limite de quantificação de 1,2 μg/kg e média de recuperação de 92%. / Mycotoxins are secondary metabolites produce by filamentous fungi that can contaminate grains in different stages of pre and postharvest management. The objective of this study was to investigate the occurrence of fungi and mycotoxins at different maturation stages of peanut produced in different regions of south of Brazil during 2006/2007 and 2007/2008 harvests. Moreover, to develop an efficient quantification method of aflatoxin B1, based on thin-layer chromatography and charged coupled device detector. Peanut samples, Tatu and Paraguaio varieties, were obtained in regions of Augusto Pestana and Ivorá, in different stages of cultura: (1) soil before planting, (2) pod filling, (3) at harvest, (4) after drying, (5) soil after harvest. The soil contamination was quantified by serial dilution technique and the fungi incidence on grains was determinate by direct planting technique. The toxigenic potential of Aspergillus section Flavi and Aspergillus section Nigri was verified in Coco Medium Ágar and Yeast Extract Sucrose agar medium, respectively. Aflatoxin B1 and ochratoxin A were determinate by on thin-layer chromatography and charged coupled device detector. The predominant species in all samples were Aspergillus flavus and Aspergillus niger var. niger. Among the species of A. flavus and A. parasiticus, 89,3% e 39,2%, produced aflatoxin B1, respectively. None of A. section Nigri isolates were ochratoxin A producers in the conditions tested. Aflatoxin B1 was detected in 50% of samples, with levels of 16.0 μg/Kg to 115.0 μg/Kg. Ochratoxin A was detected in 25% of samples, with levels of 12.2 μg/Kg to 76.9 μg/Kg. It was observed the co-occurrence of both mycotoxins in samples of postharvest. The method developed for aflatoxin B1 quantification was sensitive, efficient and practical, with a detection limit of 0.4 ng per spot, a limit of quantification of 1.2 μg/kg and average recovery of 92%.

Submitted by Mario BC (mario@bc.ufrpe.br) on 2018-05-07T16:14:12Z No. of bitstreams: 1 Steliane Lima Santos.pdf: 758334 bytes, checksum: 78af35be32365e055393819b7a1092ab (MD5) / Made available in DSpace on 2018-05-07T16:15:42Z (GMT). No. of bitstreams: 1 Steliane Lima Santos.pdf: 758334 bytes, checksum: 78af35be32365e055393819b7a1092ab (MD5) Previous issue date: 2018-02-26 / Frutosiltransferase (FTase) is an enzyme that catalyzes the breakdown of the glycosidic bonds of the sucrose molecule by transferring the fructosyl group to another molecule, which can be sucrose or fructooligosaccharides (FOS), resulting in the release of glucose. FOS is a conventional prebiotic that has a low calorimetric value and promotes the selective stimulation of the intestinal microbial growth, especially of bifidobacteria and lactobacilli, reducing the risks of cardiovascular disease, colon cancer and obesity. However to obtain the use of enzymatic processes is more expensive due to the high cost of production. However, these factors can be overcome with the use of microorganisms and agroindustrial residues as a culture medium for a solid fermentation, making the procedure more economical and feasible. The objective of this work was the production of the enzyme fructosyltransferase in solid fermentation using coffee grounds from Aspergillus flavus, where it was possible to verify that 72h of growth presented higher production of the enzyme with specific activity of 31.5 U / mg in the following conditions, 60% moisture, spore concentration 106 spores / mL at 30 ° C for 120 hours. The crude extract containing the enzyme was subjected to a precipitation selection between ketone, ammonium sulfate and ethanol, where the highest enzymatic activity was given using the precipitation with acetone 161.85 U / mL and relatively high purification factor of 10.70. Subsequently the sample was purified by DEAE SEPHADEX A50 and SUPERDEX AKTA ion exchange chromatography systems on the DEAE-sephadex system haithap and superdex 75 columns being carried out in sequence. The purified enzyme had 57 kDa molecular weight in Superdex G-75. Regarding the characterization, it presented optimum temperature of 60ºC respectively, obtaining thermo stability at 50ºC. The purification results showed a fraction with enzymatic activity for pure fructosyltransferase in which it obtained a purification factor of 86.16. When observed its enzymatic synthesis it was verified that the enzyme can produce fructooligosaccharides, being kestose and nystose. The results obtained in the present study show the promising potential of the fructosyltransferase produced by Aspergillus flavus and its use for the production of fructooligosaccharides. / Frutosiltransferase (FTase) é uma enzima que catalisa a quebra de ligações glicosídicas da molécula de sacarose transferência do grupo frutosil para uma outra molécula, podendo ser sacarose ou frutooligossacarídeos (FOS), ocorrendo a liberação de 6 glicose. O FOS é um prebiótico convencional que apresenta um baixo valor calorimétrico e promove a estimulação seletiva do crescimento microbiano intestinal, especialmente de bifidobactérias e lactobacilos, reduzindo os riscos de doenças cardiovasculares, câncer de cólon e obesidade. No entanto para obtenção a utilização de processos enzimáticos é mais caro devido ao alto custo de produção e baixa estabilidade das enzimas. Contudo esses fatores podem ser contornados com a utilização de microrganismos e resíduos agroindustriais como um meio de cultivo para uma fermentação solida, tornando o procedimento mais econômico e viável. O objetivo desse trabalho foi à produção da enzima frutosiltransferase em fermentação solida utilizando borra de café a partir de Aspergillus flavus, onde foi possível ainda verificar que 72h de crescimento apresentou maior produção da enzima com atividade especifica de 31,5 U/mg nas seguintes condições, 60% de umidade, concentração de esporos 106 esporos/mL a 30°C durante 120 horas. O extrato bruto contendo a enzima foi submetido a uma seleção de precipitação entre a cetona, sulfato de amônia e etanol, onde a maior atividade enzimática se deu utilizando a precipitação com acetona 161,85 U/mL e fator de purificação relativamente alto de 10,70. Posteriormente a amostra foi purificada através de sistema de cromatografia de troca iônica DEAE SEPHADEX A50 e SUPERDEX AKTA nas colunas DEAE-sephadex sistema haithap e superdex 75 sendo realizadas em sequência. A enzima purificada apresentou peso molecular de 57 kDa em Superdex G-75. Quanto a caracterização, apresentou temperatura ótima de 60ºC respectivamente, obtendo termo estabilidade a 50ºC. Os resultados da purificação mostraram uma fração com atividade enzimática para frutosiltransferase pura na qual obtive um fator de purificação de 86,16. Quando observado sua síntese enzimática foi constatado que a enzima consegue produzir frutooligossacarideos, sendo eles kestose e nistose. Os resultados obtidos no presente estudo mostram o potencial promissor da frutosiltransferase produzida por Aspergillus flavus e na sua utilização para produção de frutooligossacarideos.