EQA - Escola de Química e Alimentos
URI permanente desta comunidadehttps://rihomolog.furg.br/handle/1/1610
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- ItemEffect of particle size and ammonium sulfate concentration on rice bran fermentation with the fungus Rhizopus oryzae(Elsevier, 2012) Schmidt, Cristiano Gautério; Furlong, Eliana BadialeThe effects of rice bran particle size (0.18–0.39 mm) and ammonium sulfate concentration in the nutrient solution (2–8 g/L) on biomass production, protein and phenolic content generated by solid state fermentation with the fungus Rhizopus oryzae (CCT 1217) were studied. Particle size had a positive effect on biomass production and a negative effect (p 6 0.05) on protein and phenolic contents. Ammonium sulfate concentration had a positive effect (p 6 0.05) on biomass and phenolic content gain. Cultivation of fungus in rice bran with particle size of 0.18 mm and in the presence of 8 g/L ammonium sulfate, resulted in protein levels of 20 g/100 g dry wt and phenolics content of 4 mg/g dry wt. These values were 53 and 65% higher than those achieved with unfermented rice bran. The results demonstrate that the fermentation process increased the value of compounds recovered for potential use in food formulations.
- ItemMigration of mycotoxins into rice starchy endosperm during the parboiling process(Elsevier, 2009) Dors, Giniani Carla; Pinto, Luiz Antonio de Almeida; Furlong, Eliana BadialeConsidering the occurrence of rice contamination by mycotoxins and the increase in rice consumption, the present work had the objective of assessing the migration of mycotoxins into the starchy endosperm during the parboiling process, as to propose conditions that provide lower contamination levels. The newly harvested rice grain sample was examined for the natural occurrence of mycotoxins (aflatoxin B1, aflatoxin B2, deoxynivalenol, ochratoxin A, and zearalenone); only the presence of aflatoxin B1 was found (17 ng/g). The samples were then artificially contaminated with deoxynivalenol and zearalenone, and the parboiling process was conducted according to a 23 factorial planning with central point, having as variables the contamination level deoxynivalenol 720, 1440, and 2160 ng/g, and zearalenone 476, 952, and 1428 ng/g the soaking time (4, 5, and 6 h) and autoclave time (15, 22.5, and 30 min). Mycotoxins aflatoxin B1 (AFA B1), deoxynivalenol (DON), and zearalenone (ZEA) were confirmed and determined through gas chromatography. Findings showed a lower migration trend for AFA B1 under 6 h of soaking and 30 min of autoclaving, for DON under 6 h of soaking regardless of the autoclaving time, and for ZEA under 4 h of soaking and 15 min of autoclaving. This information can contribute to the choice of process parameters that limit the migration of these mycotoxins if they happen in the raw material.
- ItemEndoglucanase and total cellulase from newly isolated Rhizopus oryzae and Trichoderma reesei: production, characterization, and thermal stability(2014) Kupski, Larine; Pagnussatt, Fernanda Arnhold; Buffon, Jaqueline Garda; Furlong, Eliana BadialeA multienzymatic complex production was evaluated, as well as endoglucanase and total cellulase characterization, during solid-state fermentation of rice industry wastes with Rhizopus oryzae CCT 7560 (newly isolated microorganism) and Trichoderma reesei QM 9414 (control). R. oryzae produced enzymes with higher activity at 15 h of fermentation (5.1 and 2.3 U g−1 to endoglucanase and total cellulase), while T. reesei produced them at 55 h (15.3 and 2.8 U g−1 to endoglucanase and total cellulase). The optimum temperature for total cellulase and endoglucanase was 60 °C. For Trichoderma and Rhizopus, the optimum pH was 5.0 and 6.0 for total cellulase and 6.0 and 5.0 for endoglucanase, respectively. The enzymes produced by Rhizopus presented higher stability at the temperature range evaluated (25–100 °C); the endoglucanase KM value was 20 times lower than the one found for Trichoderma. The characterization of the cellulolytic enzymes from the fungal species native of rice husk revealed that they can be more efficient than the genetically modified enzymes when rice husk and rice bran are used as substrates.
- ItemDeoxynivalenol and nivalenol in commercial wheat grain related to Fusarium head blight epidemics in southern Brazil(2012) Del Ponte, Emerson Medeiros; Buffon, Jaqueline Garda; Furlong, Eliana BadialeA three-year (2006–2008) survey on commercial wheat grain was conducted aimed at quantifying the intensity of Fusarium head blight epidemics related to kernel quality and levels of deoxynivalenol (DON) and nivalenol (NIV). Grain samples, obtained from 38 municipalities throughout the state of Rio Grande do Sul, Brazil, were assessed visually for Fusarium-damaged kernels (FDK) and chemically using liquid chromatography–mass spectrometry (LC–MS/MS). Overall FDK mean levels were 15.5%, not differing among the years. Co-contamination was predominant (59/66) across samples and overall mean levels of DON and NIV were 540 and 337 lg/kg, respectively. When the levels of both mycotoxins were added together (DON + NIV), a higher correlation with FDK was found (R = 0.36, P < 0.01), compared to single toxin data. For the first time, the presence of NIV in levels comparable to DON is reported from a multi-year regional epidemiological survey in the country which should be of concern to the small grains industry.
- ItemAplicação de carboxipeptidase obtida de Rhizopus na degradação de ocratoxina A(2013) Kupski, Larine; Alves, Chiara Leal; Buffon, Jaqueline Garda; Furlong, Eliana BadialeMicotoxinas são metabólitos secundários produzidos por fungos filamentosos em diferentes etapas da cadeia produtiva de alimentos. Entre micotoxinas, ocratoxina A (OTA) é de grande importância, e apresenta efeitos carcinogênicos, nefrotóxicos e teratogênicos. Estes efeitos vêm motivando o desenvolvimento de métodos capazes de diminuir esta contaminação aos níveis permitidos pela legislação. Os métodos biológicos envolvendo o uso de enzimas e microorganismos para degradação da OTA tem se destacado, em função da especificidade reacional e das condições brandas para a detoxificação. Neste trabalho foram estabelecidas condições de extração de carboxipeptidase A a partir de biomassa fermentada por Rhizopus oryzae para empregá-la na degradação de OTA, tendo pancreatina como controle. A metodologia padronizada para extração enzimática consistiu em agitação ultrassônica durante 30 minutos numa potencia fixa de 150 W e 40kHz. O extrato enzimático do microorganismo apresentou uma capacidade de degradação de 19,4%, que ocasionou uma degradação 49% superior a ação da pancreatina. Este resultado confirma a vantagem da utilização de enzimas microbianas em detrimento as de origem vegetal inclusive para processos de biodegradação micotoxicologica.
- ItemActivity of rice bran proteic extracts against Fusarium graminearum(2013) Pagnussatt, Fernanda Arnhold; Bretanha, Cristiana Costa; Meza, Silvia Leticia Rivero; Buffon, Jaqueline Garda; Furlong, Eliana BadialeThe application of natural antifungal substances is motivated by the need for alternatives to existing methods that are not always applicable, efficient, or that do not pose risk to consumers or the environment. Furthermore, studies on the behaviour of toxigenic species in the presence of natural fungicides have enabled their safe application in the food chain. This study aimed to identify the fraction of the rice grain with greater inhibitory activity of amylase and related to its antifungal and antimycotoxigenic potential against Fusarium graminearum CQ 244 biomass. The greatest inhibitory effect was observed in extracts of bran, which inhibited by 90% the fungal amylase activity. The primary fractionation of the rice bran extract was more efficient when ethanolic extracts was precipitated by acetone, resulting in a specific inhibition estimated at 20 μg min-1mg protein1, PF 45 and recovery 61%. The rice bran protein extracts showed fungistatic activity against F. graminearum, with MIC50 of 419 μg ml-1 and 168 mg ml-1 estimated from glucosamine and amylase inhibition, respectively, which cause 63% biomass inhibition and 40% of the nivalenol (NIV) production.
- ItemEvaluation of the composition of culture medium for yeast biomass production using raw glycerol from biodiesel synthesis(2012) Santos, Elisane Odriosolla dos; Michelon, Mariano; Furlong, Eliana Badiale; Burkert, Janaina Fernandes de Medeiros; Kalil, Susana Juliano; Burkert, Carlos André VeigaThe work herewith investigated the production of yeast biomass as a source of protein, using Yarrowia lipolytica NRRL YB-423 and raw glycerol from biodiesel synthesis as the main carbon source. A significant influence of glycerol concentration, initial pH and yeast extract concentration on biomass and protein content was observed according to the 2v5-1 fractional design. These factors were further evaluated using a central composite design and response surface methodology, and an empirical model for protein content was established and validated. The biomass of Yarrowia lipolytica NRRL YB-423 reached 19.5 ± 1.0 g/L in shaken flasks cultivation, with a protein content of 20.1 ± 0.6% (w/w).
- ItemProfile of the Alcohols Produced in Fermentations with Malt Contaminated with Trichothecenes(2003) Reinehr, Christian Oliveira; Furlong, Eliana BadialeIn order to study the influence of mycotoxins on the production of alcohols, a fermentative process on a laboratorial scale was simulated. Malt was contaminated with deoxynivalenol and T-2 in different ratios (up to 500 ppb), according to a 32 factorial design, and the alcohols obtained after the fermentation were determined through gas chromatography. The results showed that trichothecenes influenced the profile of the alcohols produced by Saccharomyces cerevisiae during the fermentative process of malt, especially the profile of methyl and isoamyl alcohols.
- ItemArroz comercializado na região sul do Brasil: Aspectos Micotoxicologicos e Microscopicos(2003) Nunes, Itaciara Larroza; Magagnin, Glênio; Bertolin, Telma Elita; Furlong, Eliana BadialeFoi realizado um levantamento de características micotoxicológicas e microscópicas em arroz destinado ao consumo humano, comercializado nas cidades de Pelotas e Rio Grande, RS. As amostras, arroz integral [16], arroz parboilizado [16] e arroz branco polido [24] foram coletadas em supermercados, no período de maio a setembro de 2000. A avaliação de ocorrência de aflatoxinas B1, B2, G1, G2, ocratoxina A, zearalenona, desoxinivalenol e toxina T-2 foi realizada pela técnica de cromatografia de camada delgada (ccd). As duas últimas toxinas foram avaliadas também pela técnica de cromatografia gasosa (cg). A micoflora foi determinada através de plaqueamento em superfície em Ágar Batata Dextrose Acidificado, com incubação a 25ºC por 5 dias. As colônias mais freqüentes foram identificadas através da técnica de microcultivo. Dentre as amostras analisadas, duas apresentaram contaminação por ocratoxina A (104 e 128mg.Kg-1), três por zearalenona (559, 1117 e 1955mg.Kg-1), sendo uma co-contaminação com a primeira. Uma das amostras estava contaminada com desoxinivalenol (266 e 300mg.Kg-1), este quantificado por CCD e CG. Quanto à enumeração de bolores e leveduras, os resultados mostraram que 3,6% das amostras apresentaram valores superiores a 10 4 UFC.g -1 e 11% valores próximos deste. Sujidades microscópicas, acima dos limites da legislação (0,25%), foi detectada em uma amostra de arroz integral.
- ItemAvaliação Nutricional de multimisturas - Efeito de um processo fermentativo(2006) Sacchet, Fernanda Scheunemann; Machado, Adelia Ferreira de Faria; Vasconcellos, Daniele Guimarães Vasques; Soares, Leonor Almeida de Souza; Furlong, Eliana BadialeNo presente trabalho foi estudado em ratos o efeito da alteração de componentes na formulação e na fermentação por Saccharomyces cerevisae de multimistura na digestibilidade in vivo, utilização líquida de nitrogênio (NPU) e valor biológico. Com os resultados obtidos podese observar que a digestibilidade verdadeira (43,9%), o índice glicêmico (101,71mg/dL) e o ganho de peso (24,8%) indicaram que a multimistura sem folha de mandioca fermentada seria a mais indicada ao consumo humano, quando comparada às demais formulações estudadas. Sendo que, para o grupo que recebeu a dieta caseína (grupo controle) foram obtidos digestibilidade verdadeira de 97,5%, índice glicêmico de 110,29mg/dL e ganho de peso de 42,2%.