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El-Dawy EGAM, Gherbawy YA, Hussein MA. Characterization of Aspergillus section Flavi associated with stored grains. Mycotoxin Res 2024; 40:187-202. [PMID: 38231446 PMCID: PMC10834605 DOI: 10.1007/s12550-023-00514-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2023] [Revised: 12/12/2023] [Accepted: 12/14/2023] [Indexed: 01/18/2024]
Abstract
Increased frequencies of Aspergillus section Flavi and aflatoxins in cereal grains have been seen in recent years due to changes in climate circumstances, such as high temperatures and drought. To assess the microbiological risks of contamination, it is critical to have a reliable and accurate means of identifying the fungi. The main goal of this study was to characterize Aspergillus species from section Flavi obtained from twenty-three samples of barley and maize grains, gathered from different markets in Qena, Egypt, using morphological and molecular techniques. Twenty-three isolates were chosen, one isolate from each sample; they were identified as A. aflatoxiformans (4 isolates), A. flavus (18), and A. parasiticus (1). The existence of four aflatoxin biosynthesis genes was also investigated in relation to the strains' ability to produce total aflatoxins and aflatoxin B1, focusing on the regulatory gene aflR and the structural genes aflD and aflM. All strains producing aflatoxins were linked to the presence of aflR1 and/or aflR2, except two isolates that exhibited aflatoxins but from which aflR1 or aflR2 were not detected, which may be due to one or more missing or unstudied additional genes involved in aflatoxin production. AflD and aflM genes were amplified by 10 and 9 isolates, respectively. Five samples of barley and maize were contaminated by aflatoxins. Fifteen isolates were positive for producing total aflatoxins in the range of 0.1-240 ppm. Antagonistic activity of Trichoderma viride against A. flavus (F5) was assessed at 31.3%. Trichoderma reduced total aflatoxins in all treated seeds, particularly those subjected to Trichoderma formulation.
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Affiliation(s)
- Eman G A M El-Dawy
- Botany and Microbiology Department, Faculty of Science, South Valley University, Qena, Egypt.
- Applied and Environmental Microbiology Center, South Valley University, Qena, Egypt.
| | - Youssuf A Gherbawy
- Botany and Microbiology Department, Faculty of Science, South Valley University, Qena, Egypt
- Applied and Environmental Microbiology Center, South Valley University, Qena, Egypt
| | - Mohamed A Hussein
- Botany and Microbiology Department, Faculty of Science, South Valley University, Qena, Egypt
- Applied and Environmental Microbiology Center, South Valley University, Qena, Egypt
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2
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Mitema A, Feto NA. Molecular and Vegetative Compatibility Groups Characterization of Aspergillus flavus Isolates from Kenya. AIMS Microbiol 2020; 6:231-249. [PMID: 33134742 PMCID: PMC7595839 DOI: 10.3934/microbiol.2020015] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2020] [Accepted: 07/06/2020] [Indexed: 12/02/2022] Open
Abstract
The genus Aspergillus contains diverse species and the identification is complicated. Vegetative compatibility groups (VCGs) and molecular mechanisms were deployed to study the species. The study was randomly conducted in four counties in Kenya based on the history of aflatoxicosis and maize cultivation. Thirty-seven Aspergillus flavus isolates from Nandi, Kisumu, Homa Bay and Makueni were characterized to determine their taxonomic status based on their VCGs and genotypes. A phylogenetic analysis of ITS1 and ITS2 sequences of the isolates investigated revealed ITS primers discriminating some of the A. flavus isolates as 100% sequence identity to the RefSeq. Nit mutants' complementation test revealed strong heterokaryon incompatibility between isolates of Nandi region (67%) and Makueni (33%). The trend based on VCGs and molecular findings showed high incidence of toxigenic A. flavus in Makueni, which could be the reason why the region frequently experiences chronic aflatoxicosis incidences over the last few decades as compared to other regions. Interestingly, we have discovered all S and L-morphotypes including the rare S/L-morphotypes, which implies that Kenya is home to all morphotypes of A. flavus. Thus, the analysis provides a deeper understanding of the taxonomic relationship between the A. flavus isolates and could help contextualise the data obtained for each isolate with respect to VCG genetic diversity and genotypes. Determining the primary causal agents of aflatoxin contamination is critical for predicting risk of contamination events and designing and implementing effective management strategies.
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Affiliation(s)
- Alfred Mitema
- OMICS Research Group, Department of Biotechnology, Vaal University of Technology, Vanderbijlpark 1911, South Africa.,School of Biological Sciences, University of Nairobi, Nairobi, Kenya
| | - Naser Aliye Feto
- OMICS Research Group, Department of Biotechnology, Vaal University of Technology, Vanderbijlpark 1911, South Africa
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3
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Zhao G, Wang YF, Chen J, Yao Y. Predominant Mycotoxins, Pathogenesis, Control Measures, and Detection Methods in Fermented Pastes. Toxins (Basel) 2020; 12:E78. [PMID: 31979410 PMCID: PMC7076863 DOI: 10.3390/toxins12020078] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/02/2020] [Revised: 01/12/2020] [Accepted: 01/21/2020] [Indexed: 12/19/2022] Open
Abstract
Fermented pastes are some of the most popular traditional products in China. Many studies reported a strong possibility that fermented pastes promote exposure to mycotoxins, including aflatoxins, ochratoxins, and cereulide, which were proven to be carcinogenic and neurotoxic to humans. The primary mechanism of pathogenicity is by inhibiting protein synthesis and inducing oxidative stress using cytochrome P450 (CYP) enzymes. The level of mycotoxin production is dependent on the pre-harvest or post-harvest stage. It is possible to implement methods to control mycotoxins by using appropriate antagonistic microorganisms, such as Aspergillus niger, Lactobacillus plantarum, and Saccharomyces cerevisiae isolated from ordinary foods. Also, drying products as soon as possible to avoid condensation or moisture absorption in order to reduce the water activity to lower than 0.82 during storage is also effective. Furthermore, organic acid treatment during the soaking process reduces toxins by more than 90%. Some novel detection technologies based on magnetic adsorption, aptamer probes, and molecular-based methods were applied to rapidly and accurately detect mycotoxins in fermented pastes.
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Affiliation(s)
- Guozhong Zhao
- State Key Laboratory of Food Nutrition and Safety, Key Laboratory of Food Nutrition and Safety, Ministry of Education, College of Food Science and Engineering, Tianjin University of Science & Technology, 300457 Tianjin, China; (G.Z.); (Y.-F.W.)
| | - Yi-Fei Wang
- State Key Laboratory of Food Nutrition and Safety, Key Laboratory of Food Nutrition and Safety, Ministry of Education, College of Food Science and Engineering, Tianjin University of Science & Technology, 300457 Tianjin, China; (G.Z.); (Y.-F.W.)
| | - Junling Chen
- College of Food and Bioengineering, Henan University of Science and Technology, 471023 Luoyang, China;
| | - Yunping Yao
- State Key Laboratory of Food Nutrition and Safety, Key Laboratory of Food Nutrition and Safety, Ministry of Education, College of Food Science and Engineering, Tianjin University of Science & Technology, 300457 Tianjin, China; (G.Z.); (Y.-F.W.)
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4
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Effect of temperature on growth, gene expression, and aflatoxin production by Aspergillus nomius isolated from Brazil nuts. Mycotoxin Res 2019; 36:173-180. [PMID: 31828531 DOI: 10.1007/s12550-019-00380-w] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2019] [Revised: 11/21/2019] [Accepted: 11/27/2019] [Indexed: 10/25/2022]
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.
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Chang P. Genome‐wide nucleotide variation distinguishesAspergillus flavusfromAspergillus oryzaeand helps to reveal origins of atoxigenicA. flavusbiocontrol strains. J Appl Microbiol 2019; 127:1511-1520. [DOI: 10.1111/jam.14419] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2019] [Revised: 08/13/2019] [Accepted: 08/15/2019] [Indexed: 11/30/2022]
Affiliation(s)
- P.‐K. Chang
- Southern Regional Research Center Agricultural Research Service U. S. Department of Agriculture New Orleans LA USA
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6
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Frisvad J, Hubka V, Ezekiel C, Hong SB, Nováková A, Chen A, Arzanlou M, Larsen T, Sklenář F, Mahakarnchanakul W, Samson R, Houbraken J. Taxonomy of Aspergillus section Flavi and their production of aflatoxins, ochratoxins and other mycotoxins. Stud Mycol 2019; 93:1-63. [PMID: 30108412 PMCID: PMC6080641 DOI: 10.1016/j.simyco.2018.06.001] [Citation(s) in RCA: 270] [Impact Index Per Article: 54.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Aflatoxins and ochratoxins are among the most important mycotoxins of all and producers of both types of mycotoxins are present in Aspergillus section Flavi, albeit never in the same species. Some of the most efficient producers of aflatoxins and ochratoxins have not been described yet. Using a polyphasic approach combining phenotype, physiology, sequence and extrolite data, we describe here eight new species in section Flavi. Phylogenetically, section Flavi is split in eight clades and the section currently contains 33 species. Two species only produce aflatoxin B1 and B2 (A. pseudotamarii and A. togoensis), and 14 species are able to produce aflatoxin B1, B2, G1 and G2: three newly described species A. aflatoxiformans, A. austwickii and A. cerealis in addition to A. arachidicola, A. minisclerotigenes, A. mottae, A. luteovirescens (formerly A. bombycis), A. nomius, A. novoparasiticus, A. parasiticus, A. pseudocaelatus, A. pseudonomius, A. sergii and A. transmontanensis. It is generally accepted that A. flavus is unable to produce type G aflatoxins, but here we report on Korean strains that also produce aflatoxin G1 and G2. One strain of A. bertholletius can produce the immediate aflatoxin precursor 3-O-methylsterigmatocystin, and one strain of Aspergillus sojae and two strains of Aspergillus alliaceus produced versicolorins. Strains of the domesticated forms of A. flavus and A. parasiticus, A. oryzae and A. sojae, respectively, lost their ability to produce aflatoxins, and from the remaining phylogenetically closely related species (belonging to the A. flavus-, A. tamarii-, A. bertholletius- and A. nomius-clades), only A. caelatus, A. subflavus and A. tamarii are unable to produce aflatoxins. With exception of A. togoensis in the A. coremiiformis-clade, all species in the phylogenetically more distant clades (A. alliaceus-, A. coremiiformis-, A. leporis- and A. avenaceus-clade) are unable to produce aflatoxins. Three out of the four species in the A. alliaceus-clade can produce the mycotoxin ochratoxin A: A. alliaceus s. str. and two new species described here as A. neoalliaceus and A. vandermerwei. Eight species produced the mycotoxin tenuazonic acid: A. bertholletius, A. caelatus, A. luteovirescens, A. nomius, A. pseudocaelatus, A. pseudonomius, A. pseudotamarii and A. tamarii while the related mycotoxin cyclopiazonic acid was produced by 13 species: A. aflatoxiformans, A. austwickii, A. bertholletius, A. cerealis, A. flavus, A. minisclerotigenes, A. mottae, A. oryzae, A. pipericola, A. pseudocaelatus, A. pseudotamarii, A. sergii and A. tamarii. Furthermore, A. hancockii produced speradine A, a compound related to cyclopiazonic acid. Selected A. aflatoxiformans, A. austwickii, A. cerealis, A. flavus, A. minisclerotigenes, A. pipericola and A. sergii strains produced small sclerotia containing the mycotoxin aflatrem. Kojic acid has been found in all species in section Flavi, except A. avenaceus and A. coremiiformis. Only six species in the section did not produce any known mycotoxins: A. aspearensis, A. coremiiformis, A. lanosus, A. leporis, A. sojae and A. subflavus. An overview of other small molecule extrolites produced in Aspergillus section Flavi is given.
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Affiliation(s)
- J.C. Frisvad
- Department of Biotechnology and Biomedicine, DTU-Bioengineering, Technical University of Denmark, 2800 Kongens Lyngby, Denmark
| | - V. Hubka
- Department of Botany, Faculty of Science, Charles University in Prague, Benátská 2, 128 01 Prague 2, Czech Republic
- Institute of Microbiology of the CAS, v.v.i., Vídeňská 1083, 142 20 Prague 4, Czech Republic
| | - C.N. Ezekiel
- Department of Microbiology, Babcock University, Ilishan Rémo, Nigeria
| | - S.-B. Hong
- Korean Agricultural Culture Collection, National Academy of Agricultural Science, RDA, Suwon, South Korea
| | - A. Nováková
- Institute of Microbiology of the CAS, v.v.i., Vídeňská 1083, 142 20 Prague 4, Czech Republic
| | - A.J. Chen
- Institute of Medical Plant Development, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing 100193, PR China
- Westerdijk Fungal Biodiversity Institute, Uppsalalaan 8, 3584 CT Utrecht, the Netherlands
| | - M. Arzanlou
- Department of Plant Protection, University of Tabriz, Tabriz, Iran
| | - T.O. Larsen
- Department of Biotechnology and Biomedicine, DTU-Bioengineering, Technical University of Denmark, 2800 Kongens Lyngby, Denmark
| | - F. Sklenář
- Department of Botany, Faculty of Science, Charles University in Prague, Benátská 2, 128 01 Prague 2, Czech Republic
- Institute of Microbiology of the CAS, v.v.i., Vídeňská 1083, 142 20 Prague 4, Czech Republic
| | - W. Mahakarnchanakul
- Department of Food Science and Technology, Faculty of Agro-Industry, Kasetsart University, Bangkok 10900, Thailand
| | - R.A. Samson
- Westerdijk Fungal Biodiversity Institute, Uppsalalaan 8, 3584 CT Utrecht, the Netherlands
| | - J. Houbraken
- Westerdijk Fungal Biodiversity Institute, Uppsalalaan 8, 3584 CT Utrecht, the Netherlands
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Moore GG, Mack BM, Beltz SB, Puel O. Genome sequence of an aflatoxigenic pathogen of Argentinian peanut, Aspergillus arachidicola. BMC Genomics 2018; 19:189. [PMID: 29523080 PMCID: PMC5845213 DOI: 10.1186/s12864-018-4576-2] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2017] [Accepted: 03/02/2018] [Indexed: 01/06/2023] Open
Abstract
BACKGROUND Aspergillus arachidicola is an aflatoxigenic fungal species, first isolated from the leaves of a wild peanut species native to Argentina. It has since been reported in maize, Brazil nut and human sputum samples. This aflatoxigenic species is capable of secreting both B and G aflatoxins, similar to A. parasiticus and A. nomius. It has other characteristics that may result in its misidentification as one of several other section Flavi species. This study offers a preliminary analysis of the A. arachidicola genome. RESULTS In this study we sequenced the genome of the A. arachidicola type strain (CBS 117610) and found its genome size to be 38.9 Mb, and its number of predicted genes to be 12,091, which are values comparable to those in other sequenced Aspergilli. A comparison of 57 known Aspergillus secondary metabolite gene clusters, among closely-related aflatoxigenic species, revealed nearly half were predicted to exist in the type strain of A. arachidicola. Of its predicted genes, 691 were identified as unique to the species and 60% were assigned Gene Ontology terms using BLAST2GO. Phylogenomic inference shows CBS 117610 sharing a most recent common ancestor with A. parasiticus. Finally, BLAST query of A. flavus mating-type idiomorph sequences to this strain revealed the presence of a single mating-type (MAT1-1) idiomorph. CONCLUSIONS Based on A. arachidicola morphological, genetic and chemotype similarities with A. flavus and A. parasiticus, sequencing the genome of A. arachidicola will contribute to our understanding of the evolutionary relatedness among aflatoxigenic fungi.
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Affiliation(s)
- Geromy G. Moore
- Southern Regional Research Center, Agricultural Research Service, United States Department of Agriculture, 1100 Robert E Lee Blvd, New Orleans, Louisiana, 70124 USA
| | - Brian M. Mack
- Southern Regional Research Center, Agricultural Research Service, United States Department of Agriculture, 1100 Robert E Lee Blvd, New Orleans, Louisiana, 70124 USA
| | - Shannon B. Beltz
- Southern Regional Research Center, Agricultural Research Service, United States Department of Agriculture, 1100 Robert E Lee Blvd, New Orleans, Louisiana, 70124 USA
| | - Olivier Puel
- Toxalim (Research Centre in Food Toxicology), Université de Toulouse, INRA, ENVT, INP-Purpan, UPS, Toulouse, France
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Martins LM, Sant'Ana AS, Fungaro MHP, Silva JJ, Nascimento MDSD, Frisvad JC, Taniwaki MH. The biodiversity of Aspergillus section Flavi and aflatoxins in the Brazilian peanut production chain. Food Res Int 2017; 94:101-107. [PMID: 28290359 DOI: 10.1016/j.foodres.2017.02.006] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2016] [Revised: 02/07/2017] [Accepted: 02/12/2017] [Indexed: 11/17/2022]
Abstract
A total of 119 samples of peanut were collected throughout the peanut production chain in São Paulo State, Brazil. The peanut samples were directly plated for determination of percentages of infection and a polyphasic approach was used to identify Aspergillus section Flavi species. Further, the potential for aflatoxin production by the isolates was tested using the agar plug technique and the presence of aflatoxins in peanuts was assessed using an immunoaffinity column followed by quantification using HPLC with reverse phase column and fluorescence detection. The limit of detection and quantification were 0.05 and 0.17μg/kg for total aflatoxins, respectively. Four species of Aspergillus section Flavi were isolated: A. caelatus (11), A. flavus (515), A. parasiticus (17) and A. tamarii (13). All isolates of A. parasiticus were able to produce aflatoxin B and G whereas aflatoxin B was produced by 50% of A. flavus isolates. Aflatoxins were found in 12 samples at concentrations ranging from 0.3 to 100μg/kg. The data reported in this study add information on the occurrence and biodiversity of fungi in peanuts at several stages of the production chain. The occurrence of aflatoxins is also of major relevance for continuous monitoring and assessment of likely exposure of consumers to aflatoxins through consumption of peanuts.
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Affiliation(s)
- Ligia Manoel Martins
- Food Technology Institute - ITAL, Campinas, SP, Brazil; Faculty of Food Engineering, University of Campinas, Campinas, SP, Brazil.
| | | | | | | | - Maristela da Silva do Nascimento
- Food Technology Institute - ITAL, Campinas, SP, Brazil; Faculty of Food Engineering, University of Campinas, Campinas, SP, Brazil
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9
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Costa DAD, Álvares VDS, Kusdra JF, Nogueira RM, Maciel VT, Miqueloni DP. Quality of in-shell Brazil nuts after drying using a pilot natural convection oven in the state of Acre, Brazil. BRAZILIAN JOURNAL OF FOOD TECHNOLOGY 2017. [DOI: 10.1590/1981-6723.10415] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Abstract The natural drying of in-shell Brazil nuts carried out by the extractivists is not effective in reducing contamination by aflatoxin-producing fungi. Thus the use of an artificial heater could prove to be a favourable method to bring about a rapid reduction in the moisture content of the nuts and thereby prevent fungal growth. Hence the objective of this study was to evaluate the efficiency of a natural convection-type drier with respect to the physical, physicochemical and microbiological quality of nuts after drying for 6 hours at 45 °C. A random block experimental design with two treatments (nuts before and after drying) was used, using 10 replications of 3 kg. The nuts were analysed for their moisture, ash, protein, dietary fibre, total carbohydrates and lipid contents, water activity, total count of filamentous, potentially aflatoxin-producing fungi, and also the quantification of aflatoxins B1, B2, G1, G2 and the total aflatoxins. There was no effect of drying on the Aspergillus flavus and Aspergillus parasiticus counts or on the physicochemical composition of the nuts, except for the ash content. However the moisture content of the nuts was reduced by 39.7% and there was a decrease in the contamination by pre-existing total filamentous fungi. The dryer was effective in reducing the average time taken for drying as compared to the traditional method used by extractivists.
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10
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Taniwaki MH, Frisvad JC, Ferranti LS, de Souza Lopes A, Larsen TO, Fungaro MHP, Iamanaka BT. Biodiversity of mycobiota throughout the Brazil nut supply chain: From rainforest to consumer. Food Microbiol 2016; 61:14-22. [PMID: 27697164 DOI: 10.1016/j.fm.2016.08.002] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2015] [Revised: 08/08/2016] [Accepted: 08/09/2016] [Indexed: 11/29/2022]
Abstract
A total of 172 Brazil nut samples (114 in shell and 58 shelled) from the Amazon rainforest region and São Paulo state, Brazil was collected at different stages of the Brazil nut production chain: rainforest, street markets, processing plants and supermarkets. The mycobiota of the Brazil nut samples were evaluated and also compared in relation to water activity. A huge diversity of Aspergillus and Penicillium species were found, besides Eurotium spp., Zygomycetes and dematiaceous fungi. A polyphasic approach using morphological and physiological characteristics, as well as molecular and extrolite profiles, were studied to distinguish species among the more important toxigenic ones in Aspergillus section Flavi and A. section Nigri. Several metabolites and toxins were found in these two sections. Ochratoxin A (OTA) was found in 3% of A. niger and 100% of A. carbonarius. Production of aflatoxins B and G were found in all isolates of A. arachidicola, A. bombycis, A. nomius, A. pseudocaelatus and A. pseudonomius, while aflatoxin B was found in 38% of A. flavus and all isolates of A. pseudotamarii. Cyclopiazonic acid (CPA) was found in A. bertholletius (94%), A. tamarii (100%), A. caelatus (54%) and A. flavus (41%). Tenuazonic acid, a toxin commonly found in Alternaria species was produced by A. bertholletius (47%), A. caelatus (77%), A. nomius (55%), A. pseudonomius (75%), A. arachidicola (50%) and A. bombycis (100%). This work shows the changes of Brazil nut mycobiota and the potential of mycotoxin production from rainforest to consumer, considering the different environments which exist until the nuts are consumed.
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Affiliation(s)
- Marta H Taniwaki
- Instituto de Tecnologia de Alimentos - ITAL, C.P. 139, CEP 13070-178, Campinas, SP, Brazil.
| | - Jens C Frisvad
- Department of Biotechnology and Biomedicine, Technical University of Denmark, Lyngby, Denmark
| | - Larissa S Ferranti
- Instituto de Tecnologia de Alimentos - ITAL, C.P. 139, CEP 13070-178, Campinas, SP, Brazil
| | - Aline de Souza Lopes
- Instituto de Tecnologia de Alimentos - ITAL, C.P. 139, CEP 13070-178, Campinas, SP, Brazil
| | - Thomas O Larsen
- Department of Biotechnology and Biomedicine, Technical University of Denmark, Lyngby, Denmark
| | | | - Beatriz T Iamanaka
- Instituto de Tecnologia de Alimentos - ITAL, C.P. 139, CEP 13070-178, Campinas, SP, Brazil
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11
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Taniwaki MH, Pitt JI, Iamanaka BT, Massi FP, Fungaro MHP, Frisvad JC. Penicillium excelsum sp. nov from the Brazil Nut Tree Ecosystem in the Amazon Basin'. PLoS One 2015; 10:e0143189. [PMID: 26717519 PMCID: PMC4696661 DOI: 10.1371/journal.pone.0143189] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2015] [Accepted: 11/02/2015] [Indexed: 11/18/2022] Open
Abstract
A new Penicillium species, P. excelsum, is described here using morphological characters, extrolite and partial sequence data from the ITS, β-tubulin and calmodulin genes. It was isolated repeatedly using samples of nut shells and flowers from the brazil nut tree, Bertolletia excelsa, as well as bees and ants from the tree ecosystem in the Amazon rainforest. The species produces andrastin A, curvulic acid, penicillic acid and xanthoepocin, and has unique partial β-tubulin and calmodulin gene sequences. The holotype of P. excelsum is CCT 7772, while ITAL 7572 and IBT 31516 are cultures derived from the holotype.
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Affiliation(s)
- Marta Hiromi Taniwaki
- Centro de Ciência e Qualidade de Alimentos, Instituto de Tecnologia de Alimentos, Campinas, São Paulo, Brazil
- * E-mail:
| | - John I. Pitt
- CSIRO Food and Nutrition, North Ryde, New South Wales, Australia
| | - Beatriz T. Iamanaka
- Centro de Ciência e Qualidade de Alimentos, Instituto de Tecnologia de Alimentos, Campinas, São Paulo, Brazil
| | - Fernanda P. Massi
- Centro de Ciências Biológicas, Universidade Estadual de Londrina, Londrina, Paraná, Brazil
| | | | - Jens C. Frisvad
- Department of Systems Biology, Technical University of Denmark, Lyngby, Denmark
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12
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Divakara ST, Aiyaz M, Moore GG, Venkataramana M, Hariprasad P, Nayaka SC, Niranjana SR. Analysis of genetic and aflatoxin diversity amongAspergillus flavusisolates collected from sorghum seeds. J Basic Microbiol 2015; 55:1255-64. [DOI: 10.1002/jobm.201400951] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2014] [Accepted: 05/30/2015] [Indexed: 11/07/2022]
Affiliation(s)
- S. T. Divakara
- Department of Studies in Biotechnology; University of Mysore; Mysore Karnataka India
| | - M. Aiyaz
- Department of Studies in Biotechnology; University of Mysore; Mysore Karnataka India
| | - G. G. Moore
- Southern Regional Research Center; Agricultural Research Service; United States Department of Agriculture; New Orleans USA
| | - M. Venkataramana
- DRDO-BU-Centre for Life Sciences; Bharathiar University Campus; Coimbatore Tamil Nadu India
| | - P. Hariprasad
- Centre for Rural Development and Technology; Indian Institute of Technology; New Delhi India
| | - S. Chandra Nayaka
- Department of Studies in Biotechnology; University of Mysore; Mysore Karnataka India
| | - S. R. Niranjana
- Department of Studies in Biotechnology; University of Mysore; Mysore Karnataka India
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Massi FP, Penha RES, Cavalcante MC, Viaro HP, da Silva JJ, de Souza Ferranti L, Fungaro MHP. Identification of Aspergillus nomius in Bees Visiting Brazil Nut Flowers. Microbes Environ 2015; 30:273-5. [PMID: 26063353 PMCID: PMC4567567 DOI: 10.1264/jsme2.me14146] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
We designed a primer pair (BtubNomF/BtubNomR) specifically for amplifying Aspergillus nomius DNA. In vitro assays confirmed BtubNomF/BtubNomR specificity, corroborating its usefulness in detecting and identifying A. nomius. We then investigated the occurrence of A. nomius in floral visitors of Bertholletia excelsa trees by means of PCR, and A. nomius was detected in the following bees: Xylocopa frontalis, Bombus transversalis, Centris denudans, C. ferruginea, and Epicharis flava. The presence of A. nomius in bees visiting Brazil nuts opens up new avenues for obtaining novel insights into the process whereby Brazil nuts are contaminated by aflatoxin-producing fungi.
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Affiliation(s)
- Fernanda Pelisson Massi
- Centro de Ciências Biológicas, Departamento de Biologia Geral, Universidade Estadual de Londrina
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Ehrlich K, Moore G, Mellon J, Bhatnagar D. Challenges facing the biological control strategy for eliminating aflatoxin contamination. WORLD MYCOTOXIN J 2015. [DOI: 10.3920/wmj2014.1696] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Competition with Aspergillus flavus isolates incapable of aflatoxin production is currently the most widely used biocontrol method for reducing aflatoxin contamination in maize and cottonseed where aflatoxin contamination is a persistent problem for human and animal health. The method involves spreading non-aflatoxigenic A. flavus spores onto the field prior to harvest. How competition works is not fully understood. Current theories suggest that atoxigenic A. flavus either simply displaces aflatoxin-producing isolates or that competition is an active inhibition process that occurs when the fungi occupy the same locus on the plant. In this paper we describe several challenges that the biocontrol strategy should address before this practice is introduced worldwide. These include the need to better understand the diversity of A. flavus populations in the agricultural soil, the effects of climate change on both this diversity and on plant susceptibility, the ability of the introduced biocontrol strain to outcross with existing aflatoxin-producing A. flavus, the adaptation of certain A. flavus isolates for predominant growth on the plant rather than in the soil, the difficulty in timing the application or controlling the stability of the inoculum, the effect of the introduction of the biocontrol strain on the soil microenvironment, the potential damage to the plant from the introduced strain, and the overall need to better understand the entire A. flavus toxin burden, beyond that of aflatoxin, that may result from A. flavus contamination. In addition, the cost/benefit ratio for the biocontrol method should be considered in comparing this method to other methods for reducing food and feed contamination with aflatoxins.
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Affiliation(s)
- K.C. Ehrlich
- Southern Regional Research Center, USDA-ARS, 1100 RE Lee Blvd, New Orleans, LA 70124, USA
| | - G.G. Moore
- Southern Regional Research Center, USDA-ARS, 1100 RE Lee Blvd, New Orleans, LA 70124, USA
| | - J.E. Mellon
- Southern Regional Research Center, USDA-ARS, 1100 RE Lee Blvd, New Orleans, LA 70124, USA
| | - D. Bhatnagar
- Southern Regional Research Center, USDA-ARS, 1100 RE Lee Blvd, New Orleans, LA 70124, USA
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15
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Massi FP, Vieira MLC, Sartori D, Penha RES, de Freitas Munhoz C, Ferreira JM, Iamanaka BT, Taniwaki MH, Frisvad JC, Fungaro MHP. Brazil nuts are subject to infection with B and G aflatoxin-producing fungus, Aspergillus pseudonomius. Int J Food Microbiol 2014; 186:14-21. [PMID: 24974275 DOI: 10.1016/j.ijfoodmicro.2014.06.006] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2014] [Revised: 05/15/2014] [Accepted: 06/09/2014] [Indexed: 11/19/2022]
Abstract
The exploitation of the Brazil nut is one of the most important activities of the extractive communities of the Amazon rainforest. However, its commercialization can be affected by the presence of aflatoxins produced by fungi, namely Aspergillus section Flavi. In the present study, we investigated a collection of Aspergillus nomius strains isolated from Brazil nuts using different approaches, including morphological characters, RAPD and AFLP profiles, partial β-tubulin and calmodulin nucleotide sequences, aflatoxin patterns, as well as tolerance to low water activity in cultured media. Results showed that most of the isolates do belong to A. nomius species, but a few were re-identified as Aspergillus pseudonomius, a very recently described species. The results of the analyses of molecular variance, as well as the high pairwise FST values between A. nomius and A. pseudonomius suggested the isolation between these two species and the inexistence of gene flow. Fixed interspecific nucleotide polymorphisms at β-tubulin and calmodulin loci are presented. All A. pseudonomius strains analyzed produced aflatoxins AFB1, AFB2, AFG1 and AFG2. This study contains the first-ever report on the occurrence in Brazil nuts of A. pseudonomius. The G-type aflatoxins and the mycotoxin tenuazonic acid are reported here for the first time in A. pseudonomius.
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Affiliation(s)
- Fernanda Pelisson Massi
- Centro de Ciências Biológicas, Universidade Estadual de Londrina, P.O. Box 6001, Londrina 86051-990, Brazil.
| | - Maria Lúcia Carneiro Vieira
- Departamento de Genética, Escola Superior de Agricultura "Luiz de Queiroz" USP, P.O. Box 83, Piracicaba 13400-970, Brazil.
| | - Daniele Sartori
- Centro de Ciências Biológicas, Universidade Estadual de Londrina, P.O. Box 6001, Londrina 86051-990, Brazil.
| | - Rafael Elias Silva Penha
- Centro de Ciências Biológicas, Universidade Estadual de Londrina, P.O. Box 6001, Londrina 86051-990, Brazil.
| | - Carla de Freitas Munhoz
- Departamento de Genética, Escola Superior de Agricultura "Luiz de Queiroz" USP, P.O. Box 83, Piracicaba 13400-970, Brazil.
| | - Josué Maldonado Ferreira
- Centro de Ciências Biológicas, Universidade Estadual de Londrina, P.O. Box 6001, Londrina 86051-990, Brazil.
| | | | | | - Jens C Frisvad
- Department of Systems Biology, Technical University of Denmark, Lyngby, Denmark.
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16
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Midorikawa GEO, de Sousa MDLM, Freitas Silva O, Dias JDSA, Kanzaki LIB, Hanada RE, Mesquita RMLC, Gonçalves RC, Alvares VS, Bittencourt DMC, Miller RNG. Characterization of Aspergillus species on Brazil nut from the Brazilian Amazonian region and development of a PCR assay for identification at the genus level. BMC Microbiol 2014; 14:138. [PMID: 24885088 PMCID: PMC4051963 DOI: 10.1186/1471-2180-14-138] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2013] [Accepted: 05/23/2014] [Indexed: 01/29/2023] Open
Abstract
Background Brazil nut is a protein-rich extractivist tree crop in the Amazon region. Fungal contamination of shells and kernel material frequently includes the presence of aflatoxigenic Aspergillus species from the section Flavi. Aflatoxins are polyketide secondary metabolites, which are hepatotoxic carcinogens in mammals. The objectives of this study were to identify Aspergillus species occurring on Brazil nut grown in different states in the Brazilian Amazon region and develop a specific PCR method for collective identification of member species of the genus Aspergillus. Results Polyphasic identification of 137 Aspergillus strains isolated from Brazil nut shell material from cooperatives across the Brazilian Amazon states of Acre, Amapá and Amazonas revealed five species, with Aspergillus section Flavi species A. nomius and A. flavus the most abundant. PCR primers ASP_GEN_MTSSU_F1 and ASP_GEN_MTSSU_R1 were designed for the genus Aspergillus, targeting a portion of the mitochondrial small subunit ribosomal RNA gene. Primer specificity was validated through both electronic PCR against target gene sequences at Genbank and in PCR reactions against DNA from Aspergillus species and other fungal genera common on Brazil nut. Collective differentiation of the observed section Flavi species A. flavus, A. nomius and A. tamarii from other Aspergillus species was possible on the basis of RFLP polymorphism. Conclusions Given the abundance of Aspergillus section Flavi species A. nomius and A. flavus observed on Brazil nut, and associated risk of mycotoxin accumulation, simple identification methods for such mycotoxigenic species are of importance for Hazard Analysis Critical Control Point system implementation. The assay for the genus Aspergillus represents progress towards specific PCR identification and detection of mycotoxigenic species.
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Affiliation(s)
| | | | | | | | | | | | | | | | | | | | - Robert N G Miller
- Departamento de Biologia Celular, Instituto de Ciências Biológicas, Universidade de Brasília, Campus Universitário Darcy Ribeiro, CEP 70,910-900 Brasília D,F,, Brazil.
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Leite F, de Souza L, de Souza J, da C. Cartaxo C, de S. Álvares V, da Cunha C. Incidence of Aspergillus flavus, Aspergillus parasiticus and aflatoxins in Brazil nuts in the Amazon forest environment. WORLD MYCOTOXIN J 2014. [DOI: 10.3920/wmj2012.1488] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
This work aimed to evaluate, in the Amazon Forest environment, the effect of time on contamination of Brazil nuts with Aspergillus flavus, Aspergillus parasiticus and aflatoxins after falling of the pods. Samples were collected at three different times and analysed for water activity, potentially aflatoxigenic fungi A. flavus and A. parasiticus, other fungi and aflatoxins. The mean values for the parameters tested were: water activity 0.98; A. flavus and A. parasiticus 1.3×101 colony forming units (cfu)/g; other fungi 3.2×103 cfu/g; aflatoxin B1 0.073 μg/kg, aflatoxin B2 0.009 μg/kg, aflatoxin G1 0.034 μg/kg and aflatoxin G2 0.007 μg/kg. The incidence of A. flavus and A. parasiticus was not significantly affected by the time, during which the pods were on the forest soil. Moreover, aflatoxins levels were low during the whole study period, suggesting that adverse forest conditions were not the main factor that stimulate the production of aflatoxins.
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Affiliation(s)
- F.M.N. Leite
- State Secretariat for Agronomic and Forestry Extension and Small Scale Production, Rua Izaura Parente, Rio Branco, AC, 69912-000, Brazil
| | - Leite de Souza
- Federal University of Acre, Center for Biological and Nature Sciences, BR 364 km 4, Rio Branco, AC, 69915-900, Brazil
| | - J.M.L. de Souza
- Brazilian Agricultural Research Corporation, Embrapa Acre, BR 364 km 14, Rio Branco, AC, 69908-970, Brazil
| | - C.B. da C. Cartaxo
- Brazilian Agricultural Research Corporation, Embrapa Acre, BR 364 km 14, Rio Branco, AC, 69908-970, Brazil
| | - V. de S. Álvares
- Brazilian Agricultural Research Corporation, Embrapa Acre, BR 364 km 14, Rio Branco, AC, 69908-970, Brazil
| | - C.R. da Cunha
- Brazilian Agricultural Research Corporation, Embrapa Acre, BR 364 km 14, Rio Branco, AC, 69908-970, Brazil
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Luo J, Taniwaki MH, Iamanaka BT, Vogel RF, Niessen L. Application of loop-mediated isothermal amplification assays for direct identification of pure cultures of Aspergillus flavus, A. nomius, and A. caelatus and for their rapid detection in shelled Brazil nuts. Int J Food Microbiol 2013; 172:5-12. [PMID: 24361827 DOI: 10.1016/j.ijfoodmicro.2013.12.001] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2013] [Revised: 11/21/2013] [Accepted: 12/02/2013] [Indexed: 11/28/2022]
Abstract
Brazil nuts have a high nutritional content and are a very important trade commodity for some Latin American countries. Aflatoxins are carcinogenic fungal secondary metabolites. In Brazil nuts they are produced predominantly by Aspergillus (A.) nomius and A. flavus. In the present study we applied and evaluated two sets of primers previously published for the specific detection of the two species using loop-mediated isothermal amplification (LAMP) technology. Moreover, a primer set specific for A. caelatus as a frequently occurring non-aflatoxigenic member of Aspergillus section Flavi in Brazil nuts was newly developed. LAMP assays were combined with a simplified DNA release method and used for rapid identification of pure cultures and rapid detection of A. nomius and A. flavus from samples of shelled Brazil nuts. An analysis of pure cultures of 68 isolates representing the major Aspergillus species occurring on Brazil nuts showed that the three LAMP assays had individual accuracies of 61.5%, 84.4%, and 93.3% for A. flavus, A. nomius, and A. caelatus, respectively when morphological identification was used as a reference. The detection limits for conidia added directly to the individual LAMP reactions were found to be 10⁵ conidia per reaction with the primer set ID9 for A. nomius and 10⁴ conidia per reaction with the primer set ID58 for A. flavus. Sensitivity was increased to 10¹ and 10² conidia per reaction for A. nomius and A. flavus, respectively, when sample preparation included a spore disruption step. The results of LAMP assays obtained during the analysis of 32 Brazil nut samples from different regions of Brazil and from different steps in the production process of the commodity were compared with results obtained from mycological analysis and aflatoxin analysis of corresponding samples. Compared with mycological analysis of the samples, the Negative Predictive Values of LAMP assays were 42.1% and 12.5% while the Positive Predictive Values were 61.5% and 66.7% for A. nomius and A. flavus, respectively. When LAMP results were compared with the presence of aflatoxins in corresponding samples, the Negative Predictive Values were 22.2% and 44.4% and the Positive Predictive Values were 52.2% and 78.3% for aflatoxins produced by A. nomius and A. flavus, respectively. The LAMP assays described in this study have been demonstrated to be a specific, sensitive and easy to use tool for the survey of Brazil nuts for contaminations with potential aflatoxin-producing A. nomius and A. flavus in low tech environments where resources may be limited.
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Affiliation(s)
- Jie Luo
- Technische Universität München, Lehrstuhl für Technische Mikrobiologie, Gregor-Mendel-Straße 4, 85354 Freising, Germany
| | - Marta H Taniwaki
- Instituto de Tecnologia de Alimentos, C.P. 139, CEP 13070-178, Campinas, SP, Brazil
| | - Beatriz T Iamanaka
- Instituto de Tecnologia de Alimentos, C.P. 139, CEP 13070-178, Campinas, SP, Brazil
| | - Rudi F Vogel
- Technische Universität München, Lehrstuhl für Technische Mikrobiologie, Gregor-Mendel-Straße 4, 85354 Freising, Germany
| | - Ludwig Niessen
- Technische Universität München, Lehrstuhl für Technische Mikrobiologie, Gregor-Mendel-Straße 4, 85354 Freising, Germany.
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Baquião AC, de Oliveira MMM, Reis TA, Zorzete P, Diniz Atayde D, Correa B. Polyphasic approach to the identification of Aspergillus section Flavi isolated from Brazil nuts. Food Chem 2013; 139:1127-32. [DOI: 10.1016/j.foodchem.2013.01.007] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2012] [Revised: 12/28/2012] [Accepted: 01/03/2013] [Indexed: 11/16/2022]
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20
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Baquião AC, De Oliveira MMM, Reis TA, Zorzete P, Atayde DD, Corrêa B. Monitoring and determination of fungi and mycotoxins in stored Brazil nuts. J Food Prot 2013; 76:1414-20. [PMID: 23905798 DOI: 10.4315/0362-028x.jfp-13-005] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Brazil nut (Bertholletia excelsa) is an important commodity from the Brazilian Amazon, and approximately 37,000 tons (3.36 × 10⁷ kg) of Brazil nuts are harvested each year. However, substantial nut contamination by Aspergillus section Flavi occurs, with subsequent production of mycotoxins. In this context, the objective of the present investigation was to evaluate the presence of fungi and mycotoxins (aflatoxins and cyclopiazonic acid) in 110 stored samples of cultivated Brazil nut (55 samples of nuts and 55 samples of shells) collected monthly for 11 months in Itacoatiara, State of Amazonas, Brazil. The samples were inoculated in duplicate onto Aspergillus flavus and Aspergillus parasiticus agar and potato dextrose agar for the detection of fungi, and the presence of mycotoxins was determined by high-performance liquid chromatography. The most prevalent fungi in nuts and shells were Aspergillus spp., Fusarium spp., and Penicillium spp. A polyphasic approach was used for identification of Aspergillus species. Aflatoxins and cyclopiazonic acid were not detected in any of the samples analyzed. The low water activity of the substrate was a determinant factor for the presence of fungi and the absence of aflatoxin in Brazil nut samples. The high frequency of isolation of aflatoxigenic Aspergillus section Flavi strains, mainly A. flavus, and their persistence during storage increase the chances of aflatoxin production on these substrates and indicates the need for good management practices to prevent mycotoxin contamination in Brazil nuts.
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Affiliation(s)
- Arianne Costa Baquião
- Departamento de Microbiologia, Instituto de Ciências Biomédicas, Universidade de São Paulo, 05508-000 São Paulo, Brazil.
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Freitas-Silva O, Morales-Valle H, Venâncio A. Potential of aqueous ozone to control aflatoxigenic fungi in Brazil nuts. ISRN BIOTECHNOLOGY 2013; 2013:859830. [PMID: 25937982 PMCID: PMC4393033 DOI: 10.5402/2013/859830] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/31/2013] [Accepted: 06/26/2013] [Indexed: 11/23/2022]
Abstract
This study aimed to verify the use of aqueous ozone as alternative technology for fungal control. Brazil nuts sterilized were inoculated with either 1 × 106 or 1 × 107 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.
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Affiliation(s)
- Otniel Freitas-Silva
- Institute for Biotechnology and Bioengineering IBB, Centre of Biological Engineering, Universidade do Minho, Campus de Gualtar, 4710-057 Braga, Portugal ; EMBRAPA Food Technology, Avenida das Américas 29501, 23020-470 Rio de Janeiro, RJ, Brazil
| | - Héctor Morales-Valle
- Institute for Biotechnology and Bioengineering IBB, Centre of Biological Engineering, Universidade do Minho, Campus de Gualtar, 4710-057 Braga, Portugal
| | - Armando Venâncio
- Institute for Biotechnology and Bioengineering IBB, Centre of Biological Engineering, Universidade do Minho, Campus de Gualtar, 4710-057 Braga, Portugal
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22
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The biodiversity of Aspergillus section Flavi in brazil nuts: From rainforest to consumer. Int J Food Microbiol 2013; 160:267-72. [DOI: 10.1016/j.ijfoodmicro.2012.10.018] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2012] [Revised: 10/04/2012] [Accepted: 10/09/2012] [Indexed: 11/23/2022]
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23
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Reis T, Oliveira T, Baquião A, Gonçalves S, Zorzete P, Corrêa B. Mycobiota and mycotoxins in Brazil nut samples from different states of the Brazilian Amazon region. Int J Food Microbiol 2012; 159:61-8. [DOI: 10.1016/j.ijfoodmicro.2012.08.005] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2012] [Revised: 07/14/2012] [Accepted: 08/06/2012] [Indexed: 11/30/2022]
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Taniwaki MH, Pitt JI, Iamanaka BT, Sartori D, Copetti MV, Balajee A, Fungaro MHP, Frisvad JC. Aspergillus bertholletius sp. nov. from Brazil nuts. PLoS One 2012; 7:e42480. [PMID: 22952594 PMCID: PMC3428331 DOI: 10.1371/journal.pone.0042480] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2012] [Accepted: 07/06/2012] [Indexed: 11/19/2022] Open
Abstract
During a study on the mycobiota of brazil nuts (Bertholletia excelsa) in Brazil, a new Aspergillus species, A. bertholletius, was found, and is described here. A polyphasic approach was applied using morphological characters, extrolite data as well as partial β-tubulin, calmodulin and ITS sequences to characterize this taxon. A. bertholletius is represented by nineteen isolates from samples of brazil nuts at various stages of production and soil close to Bertholletia excelsa trees. The following extrolites were produced by this species: aflavinin, cyclopiazonic acid, kojic acid, tenuazonic acid and ustilaginoidin C. Phylogenetic analysis using partial β-tubulin and camodulin gene sequences showed that A. bertholletius represents a new phylogenetic clade in Aspergillus section Flavi. The type strain of A. bertholletius is CCT 7615 ( = ITAL 270/06 = IBT 29228).
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Affiliation(s)
- Marta H Taniwaki
- Centro de Ciência e Qualidade de Alimentos, Instituto de Tecnologia de Alimentos, Campinas, São Paulo, Brazil.
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