ORCID Profile
0000-0003-4314-0751
Current Organisation
Universidade de São Paulo
Does something not look right? The information on this page has been harvested from data sources that may not be up to date. We continue to work with information providers to improve coverage and quality. To report an issue, use the Feedback Form.
Publisher: MDPI AG
Date: 24-11-2009
DOI: 10.3390/IJMS10115090
Publisher: Elsevier BV
Date: 03-2017
DOI: 10.1016/J.FOODCHEM.2016.09.062
Abstract: Worldwide, barley is the main source of carbohydrate in the brewing process. However, corn is often used as an adjunct to improve and accelerate the fermentation process. Considering that, these two substrates are susceptible to fungal contamination as well as mycotoxins. The objective of the current study is to determine the incidence of the mycotoxins deoxynivalenol (DON) and fumonisin B
Publisher: MDPI AG
Date: 10-01-2019
Abstract: Fusarium species threaten yield and quality of cereals worldwide due to their ability to produce mycotoxins and cause plant diseases. Trichothecenes and zearalenone are the most economically significant mycotoxins and are of particular concern in barley, maize and wheat. For this reason, the aim of this study was to characterize the Fusarium isolates from brewing barley and to assess deoxynivalenol and zearalenone contamination in grains. Characterization of the Fusarium strains was carried out by the phylogeny based on two loci (EF-1α and RPB2). Mycotoxin detection and quantification were performed by LC-MS. The results show that Fusarium was the predominant genus. Phylogenetic study demonstrated that the majority of the strains clustered within the Fusarium sambucinum species complex followed by the Fusarium tricinctum species complex. The results revealed high incidence of deoxynivalenol (DON) and zearalenone (ZEA) contamination (90.6% and 87.5%, respectively). It was observed that 86% of the s les contaminated with ZEA were above the limits set by the EU and Brazilian regulations. These results may highlight the importance of controlling Fusarium toxins in barley, mainly because of its use in the brewing industry and the resistance of various mycotoxins to food processing treatments.
Publisher: Oxford University Press (OUP)
Date: 14-10-2019
DOI: 10.1093/GBE/EVZ225
Abstract: Fungal genomes encode highly organized gene clusters that underlie the production of specialized (or secondary) metabolites. Gene clusters encode key functions to exploit plant hosts or environmental niches. Promiscuous exchange among species and frequent reconfigurations make gene clusters some of the most dynamic elements of fungal genomes. Despite evidence for high ersity in gene cluster content among closely related strains, the microevolutionary processes driving gene cluster gain, loss, and neofunctionalization are largely unknown. We analyzed the Fusarium graminearum species complex (FGSC) composed of plant pathogens producing potent mycotoxins and causing Fusarium head blight on cereals. We de novo assembled genomes of previously uncharacterized FGSC members (two strains of F. austroamericanum, F. cortaderiae, and F. meridionale). Our analyses of 8 species of the FGSC in addition to 15 other Fusarium species identified a pangenome of 54 gene clusters within FGSC. We found that multiple independent losses were a key factor generating extant cluster ersity within the FGSC and the Fusarium genus. We identified a modular gene cluster conserved among distantly related fungi, which was likely reconfigured to encode different functions. We also found strong evidence that a rare cluster in FGSC was gained through an ancient horizontal transfer between bacteria and fungi. Chromosomal rearrangements underlying cluster loss were often complex and were likely facilitated by an enrichment in specific transposable elements. Our findings identify important transitory stages in the birth and death process of specialized metabolism gene clusters among very closely related species.
Publisher: Elsevier BV
Date: 04-2018
DOI: 10.1016/J.IJFOODMICRO.2018.02.004
Abstract: Rice (Oryza sativa L.) is one of the most important food crops worldwide. In Brazil, the southern region is the area with the highest production of rice in the country and also has a high average daily intake of rice by the population. The mycoflora, mainly toxigenic Aspergillus and Fusarium species, the presence of AFB
Publisher: Elsevier BV
Date: 31-01-2011
DOI: 10.1016/J.IJFOODMICRO.2010.11.001
Abstract: Gibberella moniliformis is most commonly associated with maize worldwide and produces high levels of fumonisins, some of the most agriculturally important mycotoxins. Studies demonstrate that molecular methods can be helpful for a rapid identification of Fusarium species and their levels of toxin production. The purpose of this research was to apply molecular methods (AFLP, TEF-1α partial gene sequencing and PCR based on MAT alleles) for the identification of Fusarium species isolated from Brazilian corn and to verify if real time RT-PCR technique based on FUM1 and FUM19 genes is appropriated to estimate fumonisins B(1) and B(2) production levels. Among the isolated strains, 96 were identified as Fusarium verticillioides, and four as other Fusarium species. Concordant phylogenies were obtained by AFLP and TEF-1α sequencing, permitting the classification of the different species into distinct clades. Concerning MAT alleles, 70% of the F. verticillioides isolates carried the MAT-1 and 30% MAT-2. A significant correlation was observed between the expression of the genes and toxin production r = 0.95 and r = 0.79 (correlation of FUM1 with FB(1) and FB(2), respectively, P < 0.0001) r = 0.93 and r = 0.78 (correlation of FUM19 with FB(1) and FB(2), respectively, P < 0.0001). Molecular methods used in this study were found to be useful for the rapid identification of Fusarium species. The high and significant correlation between FUM1 and FUM19 expression and fumonisins production suggests that real time RT-PCR is suitable for studies considering the influence of abiotic and biotic factors on expression of these genes. This is the first report concerning the expression of fumonisin biosynthetic genes in Fusarium strains isolated from Brazilian agricultural commodity.
Publisher: Springer Science and Business Media LLC
Date: 09-03-2018
DOI: 10.1007/S12550-018-0311-8
Abstract: Barley (Hordeum vulgare L.) is an important cereal crop for food and represents one of the main ingredients in beer production. Considering the importance of barley and its derived products, the knowledge about the mycotoxin contamination in the barley production is essential in order to assess its safety. In this study, the levels of deoxynivalenol (DON) and zearalenone (ZEN) in brewing barley were determined using a LC-MS/MS method. A survey was conducted in 2015 to estimate the mycotoxin levels in these products (n = 76) from four crop regions in Brazil. The results showed high levels of DON and ZEN in the analyzed s les, with contamination levels of 94 and 73.6%, respectively. The mean levels of DON and ZEN ranged from 1700 to 7500 μg/kg and from 300 to 630 μg/kg, respectively. Barley s les from regions 1 and 2 presented higher levels of ZEN and DON, respectively, and those from region 4 presented lower levels of both. Co-occurrence of DON and ZEN was seen in the majority of the barley grain s les, and the mycotoxin content was above the maximum levels established by the Brazilian and European regulations.
Publisher: Public Library of Science (PLoS)
Date: 2014
Publisher: Public Library of Science (PLoS)
Date: 21-10-2015
Publisher: Elsevier BV
Date: 05-2021
Publisher: Elsevier BV
Date: 08-2012
Publisher: Elsevier BV
Date: 2008
Publisher: Springer Science and Business Media LLC
Date: 11-12-2019
DOI: 10.1007/S12550-019-00380-W
Abstract: Aspergillus nomius is a potent producer of aflatoxins B and G and is one of the most common species of fungi found in Brazil nuts. Temperature is considered a major abiotic factor that influences fungal colonization and aflatoxin production in nuts during pre- and post-harvest. Therefore, assessment of the response of aflatoxigenic species to different temperatures is important to add information about the understanding of aflatoxin production by Aspergillus nomius and may help in the development of new strategies to prevent aflatoxin contamination. The aim of this study was to evaluate the effect of temperature (25, 30, and 35 °C) on the radial growth, aflatoxin production (B and G), and aflatoxin gene expression of seven A. nomius strains isolated from Brazil nuts. The optimal temperature for growth was 30 °C and was also the best condition for the expression of the aflR, aflD, and aflQ genes. However, maximum production of aflatoxins B and G occurred at 25 °C. Interestingly, high expression of the structural gene aflQ was observed in the maximum aflatoxin production condition (25 °C). The present study demonstrates that temperature may influence aflatoxin production by A. nomius. The combination of molecular and physiological data aids the understanding of the aflatoxigenic species response to different temperatures and can assist in predicting the driving environmental factors that influence aflatoxin contamination of Brazil nuts.
Publisher: Public Library of Science (PLoS)
Date: 09-05-2019
Publisher: Elsevier BV
Date: 09-2009
DOI: 10.1016/J.APRADISO.2009.03.004
Abstract: The objective of this study was to evaluate the effects of different gamma-radiation doses on the growth of Alternaria alternata in artificially inoculated cereal s les. Seeds and grains were ided into four groups: Control Group (not irradiated), and Groups 1, 2 and 3, inoculated with an A. alternata spore suspension (1 x 10(6) spores/mL) and exposed to 2, 5 and 10 kGy, respectively. Serial dilutions of the s les were prepared and seeded on DRBC (dichloran rose bengal chlor henicol agar) and DCMA (dichloran chlor henicol malt extract agar) media, after which the number of colony-forming units per gram was determined in each group. In addition, fungal morphology after irradiation was analyzed by scanning electron microscopy (SEM). The results showed that ionizing radiation at a dose of 5 kGy was effective in reducing the growth of A. alternata. However, a dose of 10 kGy was necessary to inhibit fungal growth completely. SEM made it possible to visualize structural alterations induced by the different gamma-radiation doses used.
Publisher: Cold Spring Harbor Laboratory
Date: 07-07-2020
DOI: 10.1101/2020.07.06.190306
Abstract: We assessed the mycobiota ersity and mycotoxin levels present in wild rice ( Oryza latifolia ) from the Pantanal region of Brazil fundamental aspects of which are severely understudied as an edible plant from a natural ecosystem. We found a variety of fungal species contaminating the rice s les the most frequent genera being Fusarium, Nigrospora and Cladosporium (35.9%, 26.1% and 15%, respectively). Within the Fusarium genus, the wild rice s les were mostly contaminated by the Fusarium incarnatum-equiseti species complex (FIESC) (80%) along with Fusarium fujikuroi species complex (20%). Phylogenetic analysis supported multiple FIESC species and gave strong support to the presence of two previously uncharacterized lineages within the complex (LN1 and LN2). Deoxynivalenol (DON) and zearalenone (ZEA) chemical analysis showed that most of the isolates were DON/ZEA producers and some were defined as high ZEA producers, displaying abundant ZEA levels over DON (over 19 times more). Suggesting that ZEA likely has a key adaptive role for FIESC in wild rice ( O. latifolia ). Mycotoxin determination in the rice s les revealed high frequency of ZEA, and 85% of rice s les had levels μg/kg the recommended limit set by regulatory agencies. DON was only detected in 5.2% of the s les. Our data shows that FIESC species are the main source of ZEA contamination in wild rice and the excessive levels of ZEA found in the rice s les raises considerable safety concerns regarding wild rice consumption by humans and animals.
Publisher: Springer Science and Business Media LLC
Date: 06-03-2017
DOI: 10.1007/S12550-017-0271-4
Abstract: Fusarium verticillioides is one of the main pathogens of maize, causing ear and stalk rots. This fungus is also able to produce high levels of fumonisins, which have been linked to various illnesses in humans and animals. Previous studies have shown that maize hybrids genetically modified with the cry genes from the bacterium Bacillus thuringiensis (Bt) presented lower incidence of F. verticillioides and fumonisin levels, presumably through the reduction of insects, which could act as vectors of fungi. The aim of this study was to assess the incidence of F. verticillioides and the concentration of fumonisins in Bt and isogenic non-Bt hybrids (2B710Hx, 30F35YG, 2B710, and 30F35, respectively). The s les of 2B710Hx and 30F35YG presented lower F. verticillioides frequency than 2B710 and 30F35 s les. However, there was no statistical difference between fumonisin contamination when Bt and non-Bt s les were compared (P > 0.05). The results suggest that other environmental parameters could possibly trigger fumonisin production during plant development in the field consequently, other management strategies should be applied to aid controlling fumonisin contamination in maize.
Publisher: Springer Science and Business Media LLC
Date: 05-11-2016
DOI: 10.1007/S12550-016-0262-X
Abstract: Bertholletia excelsa is the tree that produces Brazil nuts which have vast economic importance in the Amazon region and as an export commodity. The aim of this study was to assess the presence of Aspergillus section Nigri in Brazil nut s les at different stages of its production chain and to verify the toxigenic potential for fumonisin B
Publisher: Brill
Date: 05-2012
DOI: 10.3920/WMJ2011.1350
Abstract: Brazil contributes substantially to the global peanut production, and the state of São Paulo is the largest producer in the country. Peanut crops can be contaminated by Aspergillus flavus strains producing aflatoxins, which are highly toxic and carcinogenic. Thus, the production of high-quality peanuts is crucial both for the commercial peanut industry and as a matter of public health. In this study, we used lified fragment length polymorphism analysis (AFLP) to investigate the genetic variability among A. flavus strains isolated from fresh peanuts harvested in four different regions in the state of São Paulo, and to determine whether the molecular genetic profiles correlated with aflatoxin production or sclerotia formation. AFLP analysis generated 78 fragments ranging from 27 to 365 base pairs in length. Thirteen percent were not polymorphic. Genotyping identified twelve groups of A. flavus. On the basis of the polymorphisms identified, similarity between the isolates ranged from 37% to 100%. Of all isolates collected, 91.7% produced aflatoxins and 83.9% produced small sclerotia. Statistical analysis failed to suggest any relationship between the presence of sclerotia and mean levels of aflatoxins B 1 and B 2 . Furthermore, a dendrogram based on AFLP data revealed substantial genetic variability among the A. flavus strains, but showed no correlation between dendrogram groups separated by molecular genetic features and production of aflatoxins B 1 or B 2 or the formation of sclerotia.
Publisher: MDPI AG
Date: 12-2021
Abstract: The current study investigated the fungal ersity in freshly harvested oat s les from the two largest production regions in Brazil, Paraná (PR) and Rio Grande do Sul (RS), focusing primarily on the Fusarium genus and the presence of type B trichothecenes. The majority of the isolates belonged to the Fusarium sambucinum species complex, and were identified as F. graminearum sensu stricto (s.s.), F. meridionale, and F. poae. In the RS region, F. poae was the most frequent fungus, while F. graminearum s.s. was the most frequent in the PR region. The F. graminearum s.s. isolates were 15-ADON genotype, while F. meridionale and F. poae were NIV genotype. Mycotoxin analysis revealed that 92% and 100% of the s les from PR and RS were contaminated with type B trichothecenes, respectively. Oat grains from PR were predominantly contaminated with DON, whereas NIV was predominant in oats from RS. Twenty-four percent of the s les were contaminated with DON at levels higher than Brazilian regulations. Co-contamination of DON, its derivatives, and NIV was observed in 84% and 57.7% of the s les from PR and RS, respectively. The results provide new information on Fusarium contamination in Brazilian oats, highlighting the importance of further studies on mycotoxins.
Publisher: MDPI AG
Date: 07-05-2019
Abstract: Mycotoxins are widely studied by many research groups in all aspects, but the stability of these compounds needs further research for clarification. The objective of this study is to evaluate deoxynivalenol and zearalenone stability during all steps of the malting and brewing processes. The levels of these compounds decreased significantly during the production process (barley to beer). During the malting process, the DON levels decreased significantly in the steeping, germination, and malting steps (62%, 51.5%, and 68%, respectively). Considering ZEN, when the levels were compared between barley and the last step of the process, a significant decrease was observed. Most of the mycotoxins produced were transferred to the rootlets and spent grains, which is advantageous considering the final product. Furthermore, the mycotoxin dietary intake estimation was included in this study. The results proved that if the concentrations of target mycotoxins in raw material are under the limits established by the regulations, the levels decrease during the malting and brewing processes and make the beer secure for consumers. The quality of the five commodities involved in the beer process plays a decisive role in the creation of a safe final product.
Publisher: Cold Spring Harbor Laboratory
Date: 17-05-2019
DOI: 10.1101/639641
Abstract: Fungal genomes encode highly organized gene clusters that underlie the production of specialized (or secondary) metabolites. Gene clusters encode key functions to exploit plant hosts or environmental niches. Promiscuous exchange among species and frequent reconfigurations make gene clusters some of the most dynamic elements of fungal genomes. Despite evidence for high ersity in gene cluster content among closely related strains, the microevolutionary processes driving gene cluster gain, loss and neofunctionalization are largely unknown. We analyzed the Fusarium graminearum species complex (FGSC) composed of plant pathogens producing potent mycotoxins and causing Fusarium head blight on cereals. We de novo assembled genomes of previously uncharacterized FGSC members (two strains of F. austroamericanum , F. cortaderiae and F. meridionale ). Our analyses of eight species of the FGSC in addition to 15 other Fusarium species identified a pangenome of 54 gene clusters within FGSC. We found that multiple independent losses were a key factor generating extant cluster ersity within the FGSC and the Fusarium genus. We identified a modular gene cluster conserved among distantly related fungi, which was likely reconfigured to encode different functions. We also found strong evidence that a rare cluster in FGSC was gained through an ancient horizontal transfer between bacteria and fungi. Chromosomal rearrangements underlying cluster loss were often complex and were likely facilitated by an enrichment in specific transposable elements. Our findings identify important transitory stages in the birth and death process of specialized metabolism gene clusters among very closely related species.
Publisher: Elsevier BV
Date: 04-2017
Publisher: Frontiers Media SA
Date: 06-01-2016
Publisher: Elsevier BV
Date: 12-2009
Abstract: The objective of the present study was to evaluate the effects of different gamma radiation doses on the growth of Alternaria alternata and on the production of toxins alternariol (AOH), and alternariol monomethyl ether (AME) in sunflower seed s les. After irradiation with 2, 5 and 7 kGy, the spore mass was resuspended in sterile distilled water and the suspension was inoculated into sunflower seeds. The number of colony-forming units per gram (CFU/g) was determined after culture on Dichloran Rose Bengal Chlor henicol and Dichloran Chlor henicol Malt Extract Agar. The presence of AOH and AME was investigated by liquid chromatography coupled to mass spectrometry. The radiation doses used resulted in a reduction of the number of A. alternata CFU/g and of AOH and AME levels when compared to the nonirradiated control group. Maximum reduction of the fungus (98.5%) and toxins (99.9%) was observed at a dose of 7 and 5 kGy, respectively. Under the present conditions, gamma radiation was found to be an alternative for the control of A. alternata and, consequently, of AOH and AME production in sunflower seeds.
Publisher: Springer Science and Business Media LLC
Date: 22-11-2011
Publisher: Elsevier BV
Date: 05-2009
DOI: 10.1016/J.CBI.2009.01.005
Abstract: The aim of this study was to determine the clinical, pathological and mycotoxicological effects of oral administration of fumonisin B1 (FB1) in rabbits. Eighteen rabbits were randomly assigned to two experimental groups: control group, 0 mg FB1 fumonisin group, 31.5 mg FB1/kg body weight, corresponding to about 630 mg FB1/kg diet. Fumonisin administered as a single oral dose to rabbits resulted in acute toxicity, significantly interfering with body and liver weight. Serum biochemical analysis revealed a significant increase of total protein, alkaline phosphatase (AP), aspartate aminotransferase (AST), alanine aminotransferase (ALT), gamma-glutamyltransferase (GGT), urea and creatinine in the group receiving FB1 compared to control animals, a finding characterizing hepatic and renal injury in this group. Urinary protein concentrations were markedly elevated at 12, 24, 48 and 72 h after dosing, although visible pathological abnormalities were not observed, probably because of rapid repair of the damage. FB1 was detected in feces, with a maximum concentration at 24 h after administration, indicating that the enterohepatic circulation is important in rabbits. FB1 concentrations found in urine were low, with peak elimination at 12 h after intoxication. The highest FB1 concentrations were observed in feces compared to urine and liver, demonstrating that feces are the main routes of excretion.
No related grants have been discovered for Benedito Correa.