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Search Results: 1 - 10 of 12864 matches for " Otniel Freitas;Fonseca "
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Crescimento in vitro de fungos (Colletotrichum gloeosporioides e Cladosporium cladosporioides) isolados de frutos do mamoeiro, sob atmosfera controlada e refrigera??o
Vieira, Daniela Gouveia;Silva, Roberta Manh?es da;Silva, Otniel Freitas;Fonseca, Marcos José de Oliveira;Soares, Ant?nio Gomes;Costa, Roberto Alexandre;
Revista Brasileira de Fruticultura , 2006, DOI: 10.1590/S0100-29452006000300011
Abstract: the use of these combined technologies in tropical fruits does not present satisfactory results yet, most of the time because of the fruits injury by chilling. this injury could be intensified under atmospheric control conditions. there are evidences that the controlled atmosphere has fungistatic effect. therefore, the objective of this work was verifying, in vitro, the influence of controlled atmosphere and temperature on the two pathogenic fungi from papaya fruit: colletotrichum gloeosporioides and cladosporium cladosporioides. these fungi had been storage under two temperatures, atmospheres and period of incubation patterns (10oc and 25oc; ambient and controlled - 3% o2 and 6% co2; 7 or 14 days. after this period of storage, the contaminated plates had been incubated at 25oc under environment atmosphere for seven days more. it was verified a small growth of colletotrichum gloeosporioides under refrigeration, also after additional period at 25oc. at 25o c, the growth of this fungus was also reduced when stored under controlled atmosphere. on the other hand, it was not verified significant inhibitor effect of the controlled atmosphere at 10oc on the growth of c. gloeosporioides. the growth of cladosporium cladosporioides was reduced at 10oc in both periods of storage. after seven days at 25oc, c. cladosporioides showed a small growth in the plates that had been stored for 14 days, because the influence of the refrigeration and the controlled atmosphere. finally, the controlled atmosphere reduced the growth of the c. cladosporioides at 25oc. this effect was not observed at 10oc for c. gloeosporioides.
Extra??o e fracionamento simultaneo do óleo da castanha-do-Brasil com etanol
Freitas, Suely Pereira;Freitas-Silva, Otniel;Miranda, Iara Concei??o de;Coelho, Maria Alice Zarur;
Ciência e Tecnologia de Alimentos , 2007, DOI: 10.1590/S0101-20612007000500002
Abstract: in this work, the extraction and simultaneous separation of lipids from brazil nuts (bertholletia excelsa h.b.k.) with ethanol were investigated. brazil nuts were dried and triturated prior to oil extraction. the process was carried out at a rate of 4:1 solvent to substrate (v.w -1). the raw material and ethanol were placed in an erlenmeyer flask and maintained in a temperature-controlled bath at 65 °c and 30 rpm. after 1 hour, the mixture was filtered under a vacuum and the resultant miscella was maintained at 10 °c and centrifuged for phase separation. a rich miscella containing 75% oil and 25% ethanol was obtained presenting a gel consistency while a poor miscella, containing 2.4% oil and 97.6% ethanol, was liquid. the rich miscella presented an important potential to partially replace hydrogenate fats in the food industry. scientific studies indicated that the consumption of trans fatty acids promote serious health effects. furthermore, the proposed technology can be extended to different commercial oleaginous by eliminating the use of n-hexane in vegetable oils extraction.
Influência da calagem, da época de colheita e da secagem na incidência de fungos e aflatoxinas em gr?os de amendoim armazenados
Rossetto, Claudia Antonia Vieira;Silva, Otniel Freitas;Araújo, Antonio Edílson da Silva;
Ciência Rural , 2005, DOI: 10.1590/S0103-84782005000200010
Abstract: the objective of this work was to evaluate the effect of the storage on the potential of aflatoxin production by isolates from aspergillus flavus group in peanut (arachis hypogaea l.). these kernels were obtained from a field experiment with two areas (with or without lime), three times of harvest (104, 114 and 124 days after planting) and two types of dryer conditions (ambient and chamber with forced air). after 12 and 18 months of storage, the kernels were treated with sodium hypochloride and incubated in a pda at 20°c during five days. the isolates from aspergillus flavus group were identified after incubation in adm culture medium. the toxigenic potential was analyzed by thin layer chromatography. the genera detected were aspergillus, penicillium and fusarium. the kernels from the first harvest, showed higher contamination by the aspergillus flavus group, but the small proportion with toxigen potential.
Efeito da calagem, da colheita e da secagem na qualidade sanitária de amendoim na seca
Rossetto Claudia Antonia Vieira,Lima Tatiana de Moraes,Viegas élson de Carvalho,Silva Otniel Freitas
Pesquisa Agropecuária Brasileira , 2003,
Abstract: O objetivo deste trabalho foi avaliar o efeito da calagem, da época de colheita e do método de secagem na qualidade sanitária do amendoim (Arachis hypogaea L.), cultivar Botutatu, cultivado no campo na época da seca. O delineamento experimental foi o de blocos ao acaso em parcela subsubdividida, com quatro repeti es. As parcelas foram constituídas por ausência e presen a de calcário dolomítico (1,8 t/ha), as subparcelas, por quatro épocas de colheita, a partir de 104 dias após a semeadura, e as subsubparcelas, por duas condi es de secagem (estufa a 30oC e ambiente a 24oC e 60% de umidade relativa do ar). Em cada colheita, foi realizada a avalia o da popula o de fungos no solo, nas sementes e nas vagens, assim como do potencial de produ o de aflatoxina destes isolados. A calagem n o interfere na popula o de Aspergillus spp. no solo e n o previne sua contamina o nas vagens e nas sementes do amendoim; o atraso na época de colheita proporciona aumento da contamina o de Aspergillus flavus nas vagens e da produ o de aflatoxina G1 e G2; as condi es de secagem em ambiente propiciam maior incidência por Rhizopus spp. nas vagens e menor incidência por Aspergillus flavus nas sementes.
Potential of Aqueous Ozone to Control Aflatoxigenic Fungi in Brazil Nuts
Otniel Freitas-Silva,Héctor Morales-Valle,Armando Venancio
ISRN Biotechnology , 2013, DOI: 10.5402/2013/859830
Abstract:
Influência da calagem, da época de colheita e da secagem na incidência de fungos e aflatoxinas em gr os de amendoim armazenados
Rossetto Claudia Antonia Vieira,Silva Otniel Freitas,Araújo Antonio Edílson da Silva
Ciência Rural , 2005,
Abstract: O objetivo deste trabalho foi avaliar a contamina o e o potencial para síntese de aflatoxinas pelos isolados do grupo Aspergillus flavus em gr os armazenados de amendoim (Arachis hypogaea L.), que foram produzidos com distintos procedimentos de calagem, de colheita e de secagem. Para isto, foram avaliadas doze amostras de gr os de amendoim, cv. Botutatu, provenientes de plantas cultivadas em área que recebeu ou n o a aplica o de calcário, colhidas aos 104, 114 e 124 dias após a semeadura e secas em condi es ambientais e em estufa. Aos 12 e 18 meses de armazenamento, os gr os foram tratados com hipoclorito de sódio e incubados em BDA, a 20degreesC, por cinco dias. As espécies do grupo Aspergillus flavus foram identificadas após incuba o em meio ADM. Posteriormente, o potencial toxígeno foi avaliado pelo método da cromatografia de camada delgada. A análise da freqüência de fungos revelou que os gr os de amendoim armazenados estavam contaminados por Aspergillus spp., Penicillium spp. e Fusarium spp. Os gr os de amendoim, provenientes da colheita antecipada, apresentaram maior contamina o pelo grupo Aspergillus flavus, sendo menor a propor o destes com potencial toxígeno.
Potential of Aqueous Ozone to Control Aflatoxigenic Fungi in Brazil Nuts
Otniel Freitas-Silva,Héctor Morales-Valle,Armando Venancio
ISRN Biotechnology , 2013, DOI: 10.5402/2013/859830
Abstract: This study aimed to verify the use of aqueous ozone as alternative technology for fungal control. Brazil nuts sterilized were inoculated with either or ?conidia?mL?1 of Aspergillus flavus (MUM 9201) to determine optimal treatment parameters and different aqueous ozone contact times. These assays showed that the effect of ozone is almost immediate against A. flavus, and the optimum ozone concentration depended on the number of initial viable spores on the shell. The remaining viable spores in the ozone solution were recorded, and the rate of inactivation for each treatment was determined by assessing the ratio between the cfu of each treatment and the control. The ozonized nuts were also cultured to recover the fungal population. Aqueous ozone was effective in reducing the conidia of A. flavus and the natural fungal population associated with Brazil nuts. Aqueous ozone presented a great potential to reduce microorganisms counts in Brazil nuts with a great potential use in packing houses for decontamination step. 1. Introduction The Brazil nut (Bertholietia excelsa) is an important nontimber forest product (NTFP) from the Amazon forest. Brazil produces approximately 24% of the total world supply of this nut. Brazil nuts exploitation is an important social and economic activity for people living in forest areas. Besides this, it is an important factor in forestry conservation and environmental sustainability [1]. Despite the positive nutrition and health-related aspects of Brazil nuts, they are susceptible to colonization by mycotoxin-producing fungi and consequently to contamination with mycotoxins. There are reports of the presence of Aspergillus flavus, and A. nomius, which are the main producers of aflatoxins (AF) [2], and more recently two other aflatoxigenic species A. bombycis and A. arachidicola [3] and a new nonaflatoxigenic species A. bertholletius [4], all of them from this same section, were isolated and identified in Brazil nut samples. EU countries and the United States have been the major importers of in-shell and shelled Brazil nuts, respectively. AF contamination constitutes not only an economic problem for Brazil nut producing countries but also a serious health risk for consumers all over the world [5]. Both industries and producers have been making considerable efforts in the past 15 years to minimize fungal growth and AF contamination of tree nuts. Particularly in the case of Brazil nuts, the climate conditions in the Amazon environment and the characteristics of the exploitation activity (collecting and primary handling) cannot be
The Role and the Effects of Risk Management in IT Projects Success
Otniel DIDRAGA
Informatica Economica Journal , 2013, DOI: 10.12948/issn14531305/17.1.2013.08
Abstract: The success of IT projects is influenced by risk and risk management according to the existing project management literature. The paper emphasizes the role of risk management and its contribution to projects success in the existing literature. The methodology applied is based on documentary study review and analysis of the concepts used by the literature. We analyzed the literature published between 1978 and 2012 from the main IT project management journals and publications. The results are that risk management is a very important component of the project management process and it is assumed implicitly to work in favour of project success. We also performed a quantitative analysis of how risk management processes affect the subjective and objective performance of IT projects in Romanian IT companies.
Efeito da calagem, da colheita e da secagem na qualidade sanitária de amendoim na seca
Rossetto, Claudia Antonia Vieira;Lima, Tatiana de Moraes;Viegas, élson de Carvalho;Silva, Otniel Freitas;Bittencourt, Anna Maria;
Pesquisa Agropecuária Brasileira , 2003, DOI: 10.1590/S0100-204X2003000500003
Abstract: the objective of this work was to evaluate the effect of liming, harvest period and drying method on the sanitary quality of peanut (arachis hypogaea l.) cv. botutatu, cultivated in the field in the dry season. the experimental design was a split split plot replicated four times in completely randomized blocks. lime levels (0.0 and 1.8 ton/ha) were applied in the plots, four different harvesting periods starting at 104 days after planting were assigned to the split plots and two conditions of drying (forced air oven at 30oc and ambient at 24oc and 60% of relative humidity) were attributed to the split split plots. populations of soil fungus and fungus associated to the seeds and to the pods and aflatoxin production potential were evaluated at each harvest. there was no effect of liming on the aspergillus spp. population in soil as well as on the pods and seeds. the delay at the time of harvest provides contamination increase of aspergillus flavus in the pods and in g1 and g2 aflatoxin production; the drying conditions in ambient propitiate larger incidence for rhizopus spp. in the pods and smaller incidence for aspergillus flavus in the seeds.
Qualitative and quantitative assessment of genetically modified soy in enteral nutrition formulas by polymerase chain reaction based methods
Barros, Natália Eudes Fagundes de;Oliveira, Edna Maria Morais;Silva, Otniel Freitas;Silva, Joab Trajano;Paschoalin, Vania Margaret Flosi;
Revista de Nutri??o , 2010, DOI: 10.1590/S1415-52732010000100006
Abstract: objective: the aim of this work was to investigate the occurrence of roundup ready soybean in enteral nutrition formulas sold in brazil. methods: a duplex polymerase chain reaction based on the amplification of the lectin gene and the construction of the recombinant deoxyribonucleic acid of transgenic glyphosate-tolerant soybean (35s promoter and chloroplast transit peptide gene) was performed in order to analyze the deoxyribonucleic acid obtained from nine soy protein isolate-containing formulas. results: despite the highly processed nature of the food matrices, amplifiable deoxyribonucleic acid templates were obtained from all tested samples, as judged by the amplification of the lectin gene sequence. however, amplicons relative to the presence of roundup ready soybean were restricted to one of the nine enteral nutrition formulas analyzed as well as to the soybean reference powder, as expected. quantitative analysis of the genetically modified formula by real-time polymerase chain reaction showed a content of approximately 0.3% (w/w) of recombinant deoxyribonucleic acid from the roundup ready soybean. conclusion: the results show that one of the formulas contained genetically modified soy, pointing to the need of regulating the use of transgenic substances and of specific labeling in this product category.
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