Otniel Freitas-Silva

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The objective of this study was to quantitatively evaluate mycotoxins in samples of maize and poultry feed produced in Brazil. A multimycotoxin method based on HPLC-MS/MS was applied to investigate the occurrence of toxical fungal metabolites in 119 samples collected from poultry feed factory integrated poultry farms: maize grain (74), poultry feed (36),(More)
Ozone, a powerful oxidant, may be used for the inactivation of various microorganisms and the degradation of chemical contaminants. Although there are not many reports on the use of ozone against filamentous fungi or their mycotoxins, promising results have been reported. With a short half-time, at neutral pH and ambient temperature, ozone is able to(More)
This screening aimed to evaluate quantitatively the occurrence of fungal metabolites in Brazil nuts. Nuts were collected from Agroforest production areas in Amazon basin region. A total of 235 mycotoxins (including the most prominent ones) was screened by a multi-mycotoxin method based on HPLC-MS/MS. The recovery of metabolites by the method was between 56(More)
The Brazil nut (Bertholletia excelsa) is an economically important product to the Brazilian Amazon. Currently, its marketing is being affected by the high incidence of aflatoxins (AF) produced by potentially aflatoxigenic fungi associated with its seeds. In this context, the purpose of this study was to determine which part of the nut contributes to(More)
In the recent years the way of thinking about human health necessarily passes by human food. Recent discoveries are not only concerned about valuable biomolecules but also contaminants. Thus, the screening of substances in animal and vegetable matrices by analytical techniques is focused on the presence and absence of target substance. In both cases, the(More)
Microcrystalline cellulose (MCC) can provide improved properties when the aim is the development of biodegradable packaging materials. In this work the physicochemical properties of polysaccharide-based films (chitosan and starch) with the incorporation of MCC and the application of moderate electric field (MEF) and ultrasonic bath (UB) as treatments, were(More)
This study aimed to verify the use of aqueous ozone as alternative technology for fungal control. Brazil nuts sterilized were inoculated with either 1 × 10(6) or 1 × 10(7) 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(More)
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