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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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Djenontin E, Costa JM, Mousavi B, Nguyen LDN, Guillot J, Delhaes L, Botterel F, Dannaoui E. The Molecular Identification and Antifungal Susceptibility of Clinical Isolates of Aspergillus Section Flavi from Three French Hospitals. Microorganisms 2023; 11:2429. [PMID: 37894087 PMCID: PMC10609271 DOI: 10.3390/microorganisms11102429] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2023] [Revised: 09/20/2023] [Accepted: 09/22/2023] [Indexed: 10/29/2023] Open
Abstract
(1) Background: Aspergillus flavus is a cosmopolitan mold with medical, veterinary, and agronomic concerns. Its morphological similarity to other cryptic species of the Flavi section requires molecular identification techniques that are not routinely performed. For clinical isolates of Aspergillus section Flavi, we present the molecular identification, susceptibility to six antifungal agents, and clinical context of source patients. (2) Methods: One hundred forty fungal clinical isolates were included in the study. These isolates, recovered over a 15-year period (2001-2015), were identified based on their morphological characteristics as belonging to section Flavi. After the subculture, sequencing of a part of the β-tubulin and calmodulin genes was performed, and resistance to azole antifungals was screened on agar plates containing itraconazole and voriconazole. Minimum inhibitory concentrations were determined for 120 isolates by the European Committee on Antimicrobial Susceptibility Testing (EUCAST) broth microdilution method. (3) Results: Partial β-tubulin and calmodulin sequences analysis showed that 138/140 isolates were A. flavus sensu stricto, 1 isolate was A. parasiticus/sojae, and 1 was A. nomiae. Many of the isolates came from samples collected in the context of respiratory tract colonization. Among probable or proven aspergillosis, respiratory infections were the most frequent, followed by ENT infections. Antifungal susceptibility testing was available for isolates (n = 120, all A. flavus ss) from one hospital. The MIC range (geometric mean MIC) in mg/L was 0.5-8 (0.77), 0.5-8 (1.03), 0.125-2 (0.25), 0.03-2 (0.22), 0.25-8 (1.91), and 0.03-0.125 (0.061) for voriconazole, isavuconazole, itraconazole, posaconazole, amphotericin B, and caspofungin, respectively. Two (1.67%) isolates showed resistance to isavuconazole according to current EUCAST breakpoints with MICs at 8 mg/L for isavuconazole and voriconazole. One of these two isolates was also resistant to itraconazole with MIC at 2 mg/L. (4) Conclusions: The present characterization of a large collection of Aspergillus belonging to the Flavi section confirmed that A. flavus ss is the predominant species. It is mainly implicated in respiratory and ENT infections. The emergence of resistance highlights the need to perform susceptibility tests on section Flavi isolates.
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Affiliation(s)
- Elie Djenontin
- Dynamyc UPEC, EnvA, USC Anses, Faculté de Médecine de Créteil, 94010 Créteil, France; (E.D.); (B.M.); (F.B.)
- Service de Parasitologie-Mycologie, Hôpital Universitaire Mondor, AP-HP, 8 Rue du Général Sarrail, 94010 Créteil, France
| | - Jean-Marc Costa
- Laboratoire CERBA, 11 Rue de l’Équerre, 95310 Saint-Ouen-l’Aumône, France;
| | - Bita Mousavi
- Dynamyc UPEC, EnvA, USC Anses, Faculté de Médecine de Créteil, 94010 Créteil, France; (E.D.); (B.M.); (F.B.)
| | | | - Jacques Guillot
- Unité pédagogique de Dermatologie, Parasitologie, Mycologie, Ecole Nationale Vétérinaire Agroalimentaire et de l’Alimentation Nantes Atlantique, Oniris, 44300 Nantes, France;
| | - Laurence Delhaes
- Laboratoire de Parasitologie-Mycologie, CNR des Aspergilloses Chroniques—CHU de Bordeaux, INSERM U1045—Univ. Bordeaux, 33000 Bordeaux, France;
| | - Françoise Botterel
- Dynamyc UPEC, EnvA, USC Anses, Faculté de Médecine de Créteil, 94010 Créteil, France; (E.D.); (B.M.); (F.B.)
- Service de Parasitologie-Mycologie, Hôpital Universitaire Mondor, AP-HP, 8 Rue du Général Sarrail, 94010 Créteil, France
| | - Eric Dannaoui
- Dynamyc UPEC, EnvA, USC Anses, Faculté de Médecine de Créteil, 94010 Créteil, France; (E.D.); (B.M.); (F.B.)
- Faculté de Médecine, Université Paris Cité, 75006 Paris, France
- Unité de Parasitologie-Mycologie, Hôpital Necker Enfants Malades, AP-HP, 149 Rue de Sèvres, 75015 Paris, France
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3
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Hatmaker EA, Rangel-Grimaldo M, Raja HA, Pourhadi H, Knowles SL, Fuller K, Adams EM, Lightfoot JD, Bastos RW, Goldman GH, Oberlies NH, Rokas A. Genomic and Phenotypic Trait Variation of the Opportunistic Human Pathogen Aspergillus flavus and Its Close Relatives. Microbiol Spectr 2022; 10:e0306922. [PMID: 36318036 PMCID: PMC9769809 DOI: 10.1128/spectrum.03069-22] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2022] [Accepted: 10/10/2022] [Indexed: 11/16/2022] Open
Abstract
Fungal diseases affect millions of humans annually, yet fungal pathogens remain understudied. The mold Aspergillus flavus can cause both aspergillosis and fungal keratitis infections, but closely related species are not considered clinically relevant. To study the evolution of A. flavus pathogenicity, we examined genomic and phenotypic traits of two strains of A. flavus and three closely related species, Aspergillus arachidicola (two strains), Aspergillus parasiticus (two strains), and Aspergillus nomiae (one strain). We identified >3,000 orthologous proteins unique to A. flavus, including seven biosynthetic gene clusters present in A. flavus strains and absent in the three nonpathogens. We characterized secondary metabolite production for all seven strains under two clinically relevant conditions, temperature and salt concentration. Temperature impacted metabolite production in all species, whereas salinity did not affect production of any species. Strains of the same species produced different metabolites. Growth under stress conditions revealed additional heterogeneity within species. Using the invertebrate fungal disease model Galleria mellonella, we found virulence of strains of the same species varied widely; A. flavus strains were not more virulent than strains of the nonpathogens. In a murine model of fungal keratitis, we observed significantly lower disease severity and corneal thickness for A. arachidicola compared to other species at 48 h postinfection, but not at 72 h. Our work identifies variations in key phenotypic, chemical, and genomic attributes between A. flavus and its nonpathogenic relatives and reveals extensive strain heterogeneity in virulence that does not correspond to the currently established clinical relevance of these species. IMPORTANCE Aspergillus flavus is a filamentous fungus that causes opportunistic human infections, such as aspergillosis and fungal keratitis, but its close relatives are considered nonpathogenic. To begin understanding how this difference in pathogenicity evolved, we characterized variation in infection-relevant genomic, chemical, and phenotypic traits between strains of A. flavus and its relatives. We found extensive variation (or strain heterogeneity) within the pathogenic A. flavus as well as within its close relatives, suggesting that strain-level differences may play a major role in the ability of these fungi to cause disease. Surprisingly, we also found that the virulence of strains from species not considered to be pathogens was similar to that of A. flavus in both invertebrate and murine models of disease. These results contrast with previous studies on Aspergillus fumigatus, another major pathogen in the genus, for which significant differences in infection-relevant chemical and phenotypic traits are observed between closely related pathogenic and nonpathogenic species.
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Affiliation(s)
- E. Anne Hatmaker
- Department of Biological Sciences, Vanderbilt University, Nashville, Tennessee, USA
- Evolutionary Studies Initiative, Vanderbilt University, Nashville, Tennessee, USA
| | - Manuel Rangel-Grimaldo
- Department of Chemistry & Biochemistry, University of North Carolina at Greensboro, Greensboro, North Carolina, USA
| | - Huzefa A. Raja
- Department of Chemistry & Biochemistry, University of North Carolina at Greensboro, Greensboro, North Carolina, USA
| | - Hadi Pourhadi
- Department of Chemistry & Biochemistry, University of North Carolina at Greensboro, Greensboro, North Carolina, USA
| | - Sonja L. Knowles
- Department of Chemistry & Biochemistry, University of North Carolina at Greensboro, Greensboro, North Carolina, USA
| | - Kevin Fuller
- Department of Microbiology and Immunology, University of Oklahoma Health Science Center, Oklahoma City, Oklahoma, USA
| | - Emily M. Adams
- Department of Microbiology and Immunology, University of Oklahoma Health Science Center, Oklahoma City, Oklahoma, USA
| | - Jorge D. Lightfoot
- Department of Microbiology and Immunology, University of Oklahoma Health Science Center, Oklahoma City, Oklahoma, USA
| | - Rafael W. Bastos
- Biosciences Center, Federal University of Rio Grande do Norte, Natal, Brazil
| | - Gustavo H. Goldman
- Faculdade de Ciências Farmacêuticas de Ribeirão Preto, Universidade de São Paulo, Ribeirão Preto, Brazil
| | - Nicholas H. Oberlies
- Department of Chemistry & Biochemistry, University of North Carolina at Greensboro, Greensboro, North Carolina, USA
| | - Antonis Rokas
- Department of Biological Sciences, Vanderbilt University, Nashville, Tennessee, USA
- Evolutionary Studies Initiative, Vanderbilt University, Nashville, Tennessee, USA
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4
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Lima LMS, Okamoto DN, Passarini MRZ, Gonçalves SS, Goldman GH, Silveira MAV, Ramos PL, Cruz JB, Juliano M, Marcondes MFM, Vasconcellos SP. Enzymatic diversity of filamentous fungi isolated from forest soil incremented by sugar cane solid waste. ENVIRONMENTAL TECHNOLOGY 2022; 43:3037-3046. [PMID: 33826477 DOI: 10.1080/09593330.2021.1914179] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/06/2020] [Accepted: 03/30/2021] [Indexed: 06/12/2023]
Abstract
Fungi are natural degraders of organic matter which can produce enzymes for many industrial and biotechnological applications. In this context, crude enzymatic extracts of fungal isolates were evaluated regarding their hydrolytic and ligninolytic abilities. The fungal strains were isolated from soil samples from Atlantic Rain Forest Park incremented with sugar cane biomass (filter cake), which allowed the selection of efficient lignocellulolytic enzymes. A total of 190 fungi were isolated and evaluated by endocellulase screenings. Thirteen fungi were selected about their hydrolytic and ligninolytic abilities. Among them, three isolates showed xylanolytic activity. Eleven of the isolates were selected by their cellulolytic abilities. Proteolytic enzymes were also detected for three fungi, allowing the classification as metalloprotease and serine protease. The isolates SPZPF3_47 (Mucor sp.), SPZPF1_129 (Byssochlamys nivea) and SPZPF1_141 (Paecilomyces saturatus) were selected for further investigation on their lignin peroxidase abilities. KM, Vmax and kcat apparent for lignin peroxidases were also determined. The strain of Mucor sp. (SPZPF3_47) was highlighted since this fungal genus was not well described about its isolation in the adopted conditions in our study, and showing ligninolytic abilities.
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Affiliation(s)
- Lidiane M S Lima
- Institute of Environmental, Chemical and Pharmaceutical Sciences, Universidade Federal de São Paulo, São Paulo, Brazil
| | - Debora N Okamoto
- Institute of Environmental, Chemical and Pharmaceutical Sciences, Universidade Federal de São Paulo, São Paulo, Brazil
| | - Michel R Z Passarini
- Latin American Institute of Life and Natural Sciences, Universidade Federal da Integração Latino-Americana, Foz do Iguaçu, Brazil
| | - Sarah S Gonçalves
- Health Science Center, Universidade Federal do Espírito Santo, Espírito Santo, Brazil
| | - Gustavo H Goldman
- Faculty of Pharmaceutical Sciences of Ribeirão Preto, Universidade de São Paulo, São Paulo, Brazil
| | - Marghuel A V Silveira
- Department of Biophysics, Paulista School of Medicine, Universidade Federal de São Paulo, São Paulo, Brazil
| | | | - João B Cruz
- São Paulo Zoo Park Foundation, São Paulo, Brazil
| | - Maria Juliano
- Department of Biophysics, Paulista School of Medicine, Universidade Federal de São Paulo, São Paulo, Brazil
| | - Marcelo F M Marcondes
- Department of Biophysics, Paulista School of Medicine, Universidade Federal de São Paulo, São Paulo, Brazil
| | - Suzan P Vasconcellos
- Institute of Environmental, Chemical and Pharmaceutical Sciences, Universidade Federal de São Paulo, São Paulo, Brazil
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5
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Silva JJ, Fungaro MHP, Soto TS, Taniwaki MH, Iamanaka BT. Low-cost, specific PCR assays to identify the main aflatoxigenic species of Aspergillus section Flavi. METHODS IN MICROBIOLOGY 2022; 196:106470. [PMID: 35447279 DOI: 10.1016/j.mimet.2022.106470] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/25/2021] [Revised: 03/26/2022] [Accepted: 04/12/2022] [Indexed: 01/10/2023]
Abstract
Aflatoxins are fungal metabolites that are present as contaminants in food globally. Most aflatoxigenic species belong to Aspergillus section Flavi, and the main ones are grouped in the A. flavus clade, where many cryptic species that are difficult to discriminate are found. In this study, we investigated inter- and intraspecific diversity of the A. flavus clade to develop low-cost, species-specific PCR assays for identifying aflatoxigenic species. A total of 269 sequences of the second largest subunit of RNA polymerase II (RPB2) locus were retrieved from GenBank, and primer pairs were designed using data mining to identify A. flavus, A. parasiticus, and A. novoparasiticus. Species-specific amplicons of approximately 620, 350, and 860 bp enabled identification of target species as A. flavus, A. parasiticus, and A. novoparasiticus, respectively.
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Affiliation(s)
- Josué J Silva
- Institute of Food Technology - ITAL, Campinas, SP, Brazil.
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6
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Ben-Dor Cohen E, Ilan M, Yarden O. The Culturable Mycobiome of Mesophotic Agelas oroides: Constituents and Changes Following Sponge Transplantation to Shallow Water. J Fungi (Basel) 2021; 7:jof7070567. [PMID: 34356947 PMCID: PMC8307482 DOI: 10.3390/jof7070567] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2021] [Revised: 06/27/2021] [Accepted: 06/28/2021] [Indexed: 11/16/2022] Open
Abstract
Marine sponges harbor a diverse array of microorganisms and the composition of the microbial community has been suggested to be linked to holo-biont health. Most of the attention concerning sponge mycobiomes has been given to sponges present in shallow depths. Here, we describe the presence of 146 culturable mycobiome taxa isolated from mesophotic niche (100 m depth)-inhabiting samples of Agelas oroides, in the Mediterranean Sea. We identify some potential in vitro interactions between several A. oroides-associated fungi and show that sponge meso-hyl extract, but not its predominantly collagen-rich part, is sufficient to support hyphal growth. We demonstrate that changes in the diversity of culturable mycobiome constituents occur following sponge transplantation from its original mesophotic habitat to shallow (10 m) waters, where historically (60 years ago) this species was found. We conclude that among the 30 fungal genera identified as associated with A. oroides, Aspergillus, Penicillium and Trichoderma constitute the core mycobiome of A. oroides, and that they persist even when the sponge is transplanted to a suboptimal environment, indicative of the presence of constant, as well as dynamic, components of the sponge mycobiome. Other genera seemed more depth-related and appeared or disappeared upon host's transfer from 100 to 10 m.
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Affiliation(s)
- Eyal Ben-Dor Cohen
- School of Zoology, George S Wise Faculty of Life Sciences, Tel Aviv University, Tel Aviv 6997801, Israel; (E.B.-D.C.); (M.I.)
- Department of Plant Pathology and Microbiology, The RH Smith Faculty of Agriculture, Food and Environment, The Hebrew University of Jerusalem, Rehovot 7610001, Israel
| | - Micha Ilan
- School of Zoology, George S Wise Faculty of Life Sciences, Tel Aviv University, Tel Aviv 6997801, Israel; (E.B.-D.C.); (M.I.)
| | - Oded Yarden
- Department of Plant Pathology and Microbiology, The RH Smith Faculty of Agriculture, Food and Environment, The Hebrew University of Jerusalem, Rehovot 7610001, Israel
- Correspondence:
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7
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Abdallah MF, Audenaert K, Saeger SD, Houbraken J. Revisiting an Aspergillus flavus Strain Isolated from an Egyptian Sugarcane Field in 1930. Microorganisms 2020; 8:E1633. [PMID: 33105779 PMCID: PMC7690594 DOI: 10.3390/microorganisms8111633] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2020] [Revised: 10/21/2020] [Accepted: 10/21/2020] [Indexed: 11/17/2022] Open
Abstract
The aflatoxin type B and G producer Aspergillus novoparasiticus was described in 2012 and was firstly reported from sputum, hospital air (Brazil), and soil (Colombia). Later, several survey studies reported the occurrence of this species in different foods and other agricultural commodities from several countries worldwide. This short communication reports on an old fungal strain (CBS 108.30), isolated from Pseudococcus sacchari (grey sugarcane mealybug) from an Egyptian sugarcane field in (or before) 1930. This strain was initially identified as Aspergillus flavus; however, using the latest taxonomy schemes, the strain is, in fact, A. novoparasiticus. These data and previous reports indicate that A. novoparasiticus is strongly associated with sugarcane, and pre-harvest biocontrol approaches with non-toxigenic A. novoparasiticus strains are likely to be more successful than those using non-toxigenic A. flavus strains. Further studies on the association between A. novoparasiticus and Pseudococcus sacchari might shed light on the distribution (and aflatoxin contamination) of this species in sugarcane. Additionally, the interaction between A. novoparasiticus, Pseudococcus sacchari, and sugarcane crop under different scenarios of climate change will be critical in order to get more insight into the host-pathogen interaction and host resistance and propose appropriate prevention strategies to decrease mycotoxin contamination and crop loss due to A. novoparasiticus attack.
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Affiliation(s)
- Mohamed F. Abdallah
- Centre of Excellence in Mycotoxicology and Public Health, Department of Bioanalysis, Faculty of Pharmaceutical Sciences, Ghent University, B-9000 Ghent, Belgium;
- Laboratory of Applied Mycology and Phenomics, Department of Plants and Crops, Faculty of Bioscience Engineering, Ghent University, B-9000 Ghent, Belgium;
- Department of Forensic Medicine and Toxicology, Faculty of Veterinary Medicine, Assiut University, Assiut 71515, Egypt
| | - Kris Audenaert
- Laboratory of Applied Mycology and Phenomics, Department of Plants and Crops, Faculty of Bioscience Engineering, Ghent University, B-9000 Ghent, Belgium;
| | - Sarah De Saeger
- Centre of Excellence in Mycotoxicology and Public Health, Department of Bioanalysis, Faculty of Pharmaceutical Sciences, Ghent University, B-9000 Ghent, Belgium;
| | - Jos Houbraken
- Westerdijk Fungal Biodiversity Institute, Uppsalalaan 8, NL-3584 CT Utrecht, The Netherlands;
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M Américo F, P Machado Siqueira L, B Del Negro GM, M Favero Gimenes V, S Trindade MR, L Motta A, Santos de Freitas R, Rossi F, L Colombo A, Benard G, N de Almeida Júnior J. Evaluating VITEK MS for the identification of clinically relevant Aspergillus species. Med Mycol 2020; 58:322-327. [PMID: 31204789 DOI: 10.1093/mmy/myz066] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2019] [Revised: 05/14/2019] [Accepted: 05/24/2019] [Indexed: 12/27/2022] Open
Abstract
Aspergillus spp. identification has become more relevant in clinical practice since azole-resistant cryptic species have been related to invasive fungal infections. Conventional morphologic identification is not able to discriminate Aspergillus species, and DNA sequencing is not feasible for clinical laboratories. MALDI-TOF mass spectrometry is an emergent technology that has been explored to provide fast and accurate identification of microorganisms, including clinically relevant moulds. However, only a few studies have explored the platform VITEK MS for the identification of Aspergillus species. Hence, we provided additional data regarding the performance of the VITEK MS system for the identification of Aspergillus species, including azole-resistant ones. We also improved the RUO system by adding additional spectral profiles from well-identified Aspergillus strains belonging to different noncryptic and cryptic species. The IVD library correctly identified 91.6% of the organisms at genus and section level, and 84.7% at species level, including the azole-resistant Aspergillus lentulus and Aspergillus calidoustus. The organisms belonging to Aspergillus cryptic species had only 31.2% of correct species identification. The RUO library plus our in-house SuperSpectra correctly identified 100% of the organisms at genus and section level and 91.6% at species level. Among organisms belonging to Aspergillus cryptic species, 68.7% had correct species identification. Some closely related Aspergillus cryptic species showed similar spectral profiles and were difficult to be differentiated.
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Affiliation(s)
- Fernanda M Américo
- Laboratorio de Micologia Medica (LIM 53), Instituto de Medicina Tropical, Universidade de São Paulo, São Paulo, Brazil
| | - Lumena P Machado Siqueira
- Laboratorio de Micologia Medica (LIM 53), Instituto de Medicina Tropical, Universidade de São Paulo, São Paulo, Brazil
| | - Gilda Maria B Del Negro
- Laboratorio de Micologia Medica (LIM 53), Instituto de Medicina Tropical, Universidade de São Paulo, São Paulo, Brazil
| | - Viviane M Favero Gimenes
- Laboratorio de Micologia Medica (LIM 53), Instituto de Medicina Tropical, Universidade de São Paulo, São Paulo, Brazil
| | - Mario Roberto S Trindade
- Laboratório Especial de Micologia, Disciplina de Infectologia, Universidade Federal de São Paulo, São Paulo, Brazil
| | - Adriana L Motta
- Laboratorio de Micologia Medica (LIM 53), Instituto de Medicina Tropical, Universidade de São Paulo, São Paulo, Brazil
| | - Roseli Santos de Freitas
- Laboratorio de Micologia Medica (LIM 53), Instituto de Medicina Tropical, Universidade de São Paulo, São Paulo, Brazil
| | - Flavia Rossi
- Laboratório Central (LIM 03), Hospital das Clínicas da Faculdade de Medicina da Universidade de São Paulo, São Paulo, Brazil
| | - Arnaldo L Colombo
- Laboratório Especial de Micologia, Disciplina de Infectologia, Universidade Federal de São Paulo, São Paulo, Brazil
| | - Gil Benard
- Laboratorio de Micologia Medica (LIM 53), Instituto de Medicina Tropical, Universidade de São Paulo, São Paulo, Brazil
| | - João N de Almeida Júnior
- Laboratorio de Micologia Medica (LIM 53), Instituto de Medicina Tropical, Universidade de São Paulo, São Paulo, Brazil.,Laboratório Especial de Micologia, Disciplina de Infectologia, Universidade Federal de São Paulo, São Paulo, Brazil.,Laboratório Central (LIM 03), Hospital das Clínicas da Faculdade de Medicina da Universidade de São Paulo, São Paulo, Brazil
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9
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Barros Correia ACR, Barbosa RN, Frisvad JC, Houbraken J, Souza-Motta CM. The polyphasic re-identification of a Brazilian Aspergillus section Terrei collection led to the discovery of two new species. Mycol Prog 2020. [DOI: 10.1007/s11557-020-01605-4] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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10
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Abstract
The taxonomy and nomenclature of the genus Aspergillus and its associated sexual (teleomorphic) genera have been greatly stabilised over the last decade. This was in large thanks to the accepted species list published in 2014 and associated metadata such as DNA reference sequences released at the time. It had a great impact on the community and it has never been easier to identify, publish and describe the missing Aspergillus diversity. To further stabilise its taxonomy, it is crucial to not only discover and publish new species but also to capture infraspecies variation in the form of DNA sequences. This data will help to better characterise and distinguish existing species and make future identifications more robust. South Africa has diverse fungal communities but remains largely unexplored in terms of Aspergillus with very few sequences available for local strains. In this paper, we re-identify Aspergillus previously accessioned in the PPRI and MRC culture collections using modern taxonomic approaches. In the process, we re-identify strains to 63 species, describe seven new species and release a large number of new DNA reference sequences.
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Affiliation(s)
- C.M. Visagie
- Department of Biochemistry, Genetics and Microbiology, Forestry and Agricultural Biotechnology Institute (FABI), University of Pretoria, Pretoria, South Africa
- Biosystematics Division, Agricultural Research Council – Plant Health and Protection, Private Bag X134, Queenswood, Pretoria, 0121, South Africa
| | - J. Houbraken
- Westerdijk Fungal Biodiversity Institute, Uppsalalaan 8, Utrecht, CT, 3584, Netherlands
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12
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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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Uka V, Moore GG, Arroyo-Manzanares N, Nebija D, De Saeger S, Diana Di Mavungu J. Secondary Metabolite Dereplication and Phylogenetic Analysis Identify Various Emerging Mycotoxins and Reveal the High Intra-Species Diversity in Aspergillus flavus. Front Microbiol 2019; 10:667. [PMID: 31024476 PMCID: PMC6461017 DOI: 10.3389/fmicb.2019.00667] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2018] [Accepted: 03/18/2019] [Indexed: 12/18/2022] Open
Abstract
Aspergillus flavus is one of the most important mycotoxigenic species from the genus Aspergillus, due to its ability to synthesize the potent hepatocarcinogen, aflatoxin B1. Moreover, this fungus is capable of producing several other toxic metabolites from the class of indole-tetramates, non-ribosomal peptides, and indole-diterpenoids. Populations of A. flavus are characterized by considerable diversity in terms of morphological, functional and genetic features. Although for many years A. flavus was considered an asexual fungus, researchers have shown evidence that at best these fungi can exhibit a predominantly asexual existence. We now know that A. flavus contains functional genes for mating, uncovering sexuality as potential contributor for its diversification. Based on our results, we reconfirm that A. flavus is a predominant producer of B-type aflatoxins. Moreover, this fungus can decisively produce AFM1 and AFM2. We did not observe any clear relationship between mating-type genes and particular class of metabolites, probably other parameters such as sexual/asexual ratio should be investigated. A dynamic secondary metabolism was found also in strains intended to be used as biocontrol agents. In addition we succeeded to provide mass spectrometry fragmentation spectra for the most important classes of A. flavus metabolites, which will serve as identification cards for future studies. Both, metabolic and phylogenetic analysis proved a high intra-species diversity for A. flavus. These findings contribute to our understanding about the diversity of Aspergillus section Flavi species, raising the necessity for polyphasic approaches (morphological, metabolic, genetic, etc.) when dealing with this type of complex group of species.
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Affiliation(s)
- Valdet Uka
- Center of Excellence in Mycotoxicology and Public Health, Faculty of Pharmaceutical Sciences, Ghent University, Ghent, Belgium.,Department of Pharmacy, Faculty of Medicine, University of Prishtina, Prishtina, Kosovo†
| | - Geromy G Moore
- Southern Regional Research Center, Agricultural Research Service, United States Department of Agriculture, New Orleans, LA, United States
| | - Natalia Arroyo-Manzanares
- Department of Analytical Chemistry, Faculty of Chemistry, Regional Campus of International Excellence "Campus Mare-Nostrum", University of Murcia, Murcia, Spain
| | - Dashnor Nebija
- Department of Pharmacy, Faculty of Medicine, University of Prishtina, Prishtina, Kosovo†
| | - Sarah De Saeger
- Center of Excellence in Mycotoxicology and Public Health, Faculty of Pharmaceutical Sciences, Ghent University, Ghent, Belgium
| | - José Diana Di Mavungu
- Center of Excellence in Mycotoxicology and Public Health, Faculty of Pharmaceutical Sciences, Ghent University, Ghent, Belgium
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Moore G, Lebar M, Carter‐Wientjes C. The role of extrolites secreted by nonaflatoxigenicAspergillus flavusin biocontrol efficacy. J Appl Microbiol 2019; 126:1257-1264. [DOI: 10.1111/jam.14175] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2018] [Revised: 10/09/2018] [Accepted: 12/06/2018] [Indexed: 11/30/2022]
Affiliation(s)
- G.G. Moore
- US Department of Agriculture Agricultural Research Service, Southern Regional Research Center New Orleans LA USA
| | - M.D. Lebar
- US Department of Agriculture Agricultural Research Service, Southern Regional Research Center New Orleans LA USA
| | - C.H. Carter‐Wientjes
- US Department of Agriculture Agricultural Research Service, Southern Regional Research Center New Orleans LA USA
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Silva JJ, Puel O, Lorber S, Ferranti LS, Ortiz LF, Taniwaki MH, Iamanaka BT, Fungaro MHP. Occurrence and diversity of Aspergillus in commercial yerba mate elaborated for the Brazilian beverage 'chimarrão'. Food Res Int 2019; 121:940-946. [PMID: 31108829 DOI: 10.1016/j.foodres.2019.01.023] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2018] [Revised: 01/08/2019] [Accepted: 01/09/2019] [Indexed: 01/01/2023]
Abstract
Dried leaves and stems of Ilex paraguariensis St. Hil. (yerba mate) are used to make a popular beverage in some countries of South America, commonly known as "chimarrão". The present study was designed to evaluate the occurrence of toxigenic Aspergillus in yerba mate in order to define the mycotoxin risk associated with this foodstuff. All samples tested were positive for fungal contamination, and the fungal load per sample ranged from 2.0 × 102 to 1.6 × 104 CFU/g. Aspergillus section Nigri was found in all samples and represented 76.5% of the total fungi isolated. Aspergillus section Circumdati, Aspergillus section Flavi and Aspergillus section Cremei were found at low frequencies. Thirteen different Aspergillus species were identified. The most common species found was A. luchuensis, which does not produce any harmful toxin for humans. A. niger, A. welwitschiae, A. flavus and A. novoparasiticus, all potentially toxigenic species, were found only in small quantities. The A. niger and A. welwitschiae strains were cultured to test for ochratoxin A and fumonisin B2 production. Only one strain producing ochratoxin A was found, but approximately 29% of the strains were positive for fumonisin B2. The A. flavus and A. novoparasiticus strains were tested for aflatoxins production, and 63% were positive. A. pallidofulvus, recently assigned to A. section Circumdati, was reported for the first time in herbs. All A. pallidofulvus strains analyzed in this study were negative for ochratoxin A production. In conclusion, A. section Nigri occurs with high frequency in yerba mate, and A. luchuensis is the predominant species. Although toxigenic species were found in this herb, the incidence was low.
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Affiliation(s)
- Josué José Silva
- Centro de Ciências Biológicas, Universidade Estadual de Londrina, P. O. Box 6001, Londrina 86051-990, Brazil
| | - Olivier Puel
- Toxalim (Research Centre in Food Toxicology), Université de Toulouse, INRA, ENVT, INP-Purpan, UPS, 31027 Toulouse, France
| | - Sophie Lorber
- Toxalim (Research Centre in Food Toxicology), Université de Toulouse, INRA, ENVT, INP-Purpan, UPS, 31027 Toulouse, France
| | - Larissa S Ferranti
- Instituto de Tecnologia de Alimentos, P.O. Box 139, Campinas 13070-178, Brazil
| | - Luryan F Ortiz
- Centro de Ciências Biológicas, Universidade Estadual de Londrina, P. O. Box 6001, Londrina 86051-990, Brazil
| | - Marta H Taniwaki
- Instituto de Tecnologia de Alimentos, P.O. Box 139, Campinas 13070-178, Brazil
| | - Beatriz T Iamanaka
- Instituto de Tecnologia de Alimentos, P.O. Box 139, Campinas 13070-178, Brazil
| | - Maria Helena P Fungaro
- Centro de Ciências Biológicas, Universidade Estadual de Londrina, P. O. Box 6001, Londrina 86051-990, Brazil.
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Iamanaka BT, de Souza Lopes A, Martins LM, Frisvad JC, Medina A, Magan N, Sartori D, Massi FP, Fungaro MHP, Taniwaki MH. Aspergillus section Flavi diversity and the role of A. novoparasiticus in aflatoxin contamination in the sugarcane production chain. Int J Food Microbiol 2018; 293:17-23. [PMID: 30634067 DOI: 10.1016/j.ijfoodmicro.2018.12.024] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2018] [Revised: 12/12/2018] [Accepted: 12/22/2018] [Indexed: 10/27/2022]
Abstract
The presence of Aspergillus section Flavi and aflatoxins in sugarcane as well as in by-products, such as molasses, sugar, yeast cream and dried yeast, collected from different fields and processing plants in São Paulo state, were investigated throughout the sugarcane production chain. A total of 246 samples was collected and analyzed and 226 isolates of Aspergillus section Flavi were isolated. Aspergillus section Flavi strains were found in sugarcane juice, milled sugarcane, stalk, soil and dried yeast samples. Among the isolates of Aspergillus section Flavi submitted to polyphasic identification (n = 57), Aspergillus novoparasiticus and Aspergillus arachidicola were predominantly found. A significant proportion of the isolates (84.5%) were found to have morphological and physiological characteristics of A. novoparasiticus. Most samples, with the exception of sugar, showed some aflatoxin contamination. The highest level was in dried yeast with an average of 2.55 μg/kg and maximum value of 10.19 μg/kg. This is the first report of contamination of sugarcane by A. novoparasiticus.
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Affiliation(s)
| | - Aline de Souza Lopes
- Faculty of Food Engineering, University of Campinas - UNICAMP, Campinas, SP, Brazil
| | - Ligia Manoel Martins
- Microbiology Laboratory, Food Technology Institute - ITAL, Campinas, SP, Brazil; Faculty of Food Engineering, University of Campinas - UNICAMP, Campinas, SP, Brazil
| | | | - Angel Medina
- Cranfield University, Applied Mycology Group, Beds. MK43 0Al, United Kingdom
| | - Naresh Magan
- Cranfield University, Applied Mycology Group, Beds. MK43 0Al, United Kingdom
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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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19
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Katsurayama AM, Martins LM, Iamanaka BT, Fungaro MHP, Silva JJ, Frisvad JC, Pitt JI, Taniwaki MH. Occurrence of Aspergillus section Flavi and aflatoxins in Brazilian rice: From field to market. Int J Food Microbiol 2018; 266:213-221. [DOI: 10.1016/j.ijfoodmicro.2017.12.008] [Citation(s) in RCA: 33] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2017] [Revised: 12/05/2017] [Accepted: 12/08/2017] [Indexed: 11/29/2022]
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20
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LAMP-based group specific detection of aflatoxin producers within Aspergillus section Flavi in food raw materials, spices, and dried fruit using neutral red for visible-light signal detection. Int J Food Microbiol 2017; 266:241-250. [PMID: 29272724 DOI: 10.1016/j.ijfoodmicro.2017.12.013] [Citation(s) in RCA: 30] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2017] [Revised: 12/13/2017] [Accepted: 12/14/2017] [Indexed: 01/10/2023]
Abstract
Aflatoxins can be produced by 21 species within sections Flavi (16 species), Ochraceorosei (2), and Nidulantes (3) of the fungal genus Aspergillus. They pose risks to human and animal health due to high toxicity and carcinogenicity. Detecting aflatoxin producers can help to assess toxicological risks associated with contaminated commodities. Species specific molecular assays (PCR and LAMP) are available for detection of major producers, but fail to detect species of minor importance. To enable rapid and sensitive detection of several aflatoxin producing species in a single analysis, a nor1 gene-specific LAMP assay was developed. Specificity testing showed that among 128 fungal species from 28 genera, 15 aflatoxigenic species in section Flavi were detected, including synonyms of A. flavus and A. parasiticus. No cross reactions were found with other tested species. The detection limit of the assay was 9.03pg of A. parasiticus genomic DNA per reaction. Visual detection of positive LAMP reactions under daylight conditions was facilitated using neutral red to allow unambiguous distinction between positive and negative assay results. Application of the assay to the detection of A. parasiticus conidia revealed a detection limit of 211 conidia per reaction after minimal sample preparation. The usefulness of the assay was demonstrated in the analysis of aflatoxinogenic species in samples of rice, nuts, raisins, dried figs, as well as powdered spices. Comparison of LAMP results with presence/absence of aflatoxins and aflatoxin producing fungi in 50 rice samples showed good correlation between these parameters. Our study suggests that the developed LAMP assay is a rapid, sensitive and user-friendly tool for surveillance and quality control in our food industry.
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Carvajal-Campos A, Manizan AL, Tadrist S, Akaki DK, Koffi-Nevry R, Moore GG, Fapohunda SO, Bailly S, Montet D, Oswald IP, Lorber S, Brabet C, Puel O. Aspergillus korhogoensis, a Novel Aflatoxin Producing Species from the Côte d'Ivoire. Toxins (Basel) 2017; 9:E353. [PMID: 29088078 PMCID: PMC5705968 DOI: 10.3390/toxins9110353] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2017] [Revised: 10/13/2017] [Accepted: 10/26/2017] [Indexed: 12/12/2022] Open
Abstract
Several strains of a new aflatoxigenic species of Aspergillus, A. korhogoensis, were isolated in the course of a screening study involving species from section Flavi found contaminating peanuts (Arachis hypogaea) and peanut paste in the Côte d'Ivoire. Based on examination of four isolates, this new species is described using a polyphasic approach. A concatenated alignment comprised of nine genes (ITS, benA, cmdA, mcm7, amdS, rpb1, preB, ppgA, and preA) was subjected to phylogenetic analysis, and resulted in all four strains being inferred as a distinct clade. Characterization of mating type for each strain revealed A. korhogoensis as a heterothallic species, since three isolates exhibited a singular MAT1-1 locus and one isolate exhibited a singular MAT1-2 locus. Morphological and physiological characterizations were also performed based on their growth on various types of media. Their respective extrolite profiles were characterized using LC/HRMS, and showed that this new species is capable of producing B- and G-aflatoxins, aspergillic acid, cyclopiazonic acid, aflavarins, and asparasones, as well as other metabolites. Altogether, our results confirm the monophyly of A. korhogoensis, and strengthen its position in the A. flavus clade, as the sister taxon of A. parvisclerotigenus.
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Affiliation(s)
- Amaranta Carvajal-Campos
- Toxalim (Research Centre in Food Toxicology), Université de Toulouse, INRA, ENVT, INP-Purpan, UPS, 31027 Toulouse, France.
| | - Ama Lethicia Manizan
- Laboratoire de Biotechnologie et Microbiologie des Aliments, UFR des Sciences et Technologie des Aliments, Université Nangui Abrogoua, 02 BP 801 Abidjan, Côte d'Ivoire.
| | - Souria Tadrist
- Toxalim (Research Centre in Food Toxicology), Université de Toulouse, INRA, ENVT, INP-Purpan, UPS, 31027 Toulouse, France.
| | - David Koffi Akaki
- Laboratoire des Procédés Industriels de Synthèse, de l'Environnement et des Energies Nouvelles, Département Génie Chimique et Agro-alimentaire, Institut National Polytechnique Félix Houphouët-Boigny, BP 1313 Yamoussoukro, Côte d'Ivoire.
| | - Rose Koffi-Nevry
- Laboratoire de Biotechnologie et Microbiologie des Aliments, UFR des Sciences et Technologie des Aliments, Université Nangui Abrogoua, 02 BP 801 Abidjan, Côte d'Ivoire.
| | - Geromy G Moore
- Southern Regional Research Center, Agricultural Research Service, United States Department of Agriculture, New Orleans, LA 70179, USA.
| | - Stephen O Fapohunda
- Department of Microbiology, Babcock University, 23401 Ilishan Remo, Nigeria.
| | - Sylviane Bailly
- Toxalim (Research Centre in Food Toxicology), Université de Toulouse, INRA, ENVT, INP-Purpan, UPS, 31027 Toulouse, France.
| | - Didier Montet
- Centre de Coopération Internationale en Recherche Agronomique pour le Développement (CIRAD)-Département PERSYST-UMR QualiSud, 34398 Montpellier, France.
| | - Isabelle P Oswald
- Toxalim (Research Centre in Food Toxicology), Université de Toulouse, INRA, ENVT, INP-Purpan, UPS, 31027 Toulouse, France.
| | - Sophie Lorber
- Toxalim (Research Centre in Food Toxicology), Université de Toulouse, INRA, ENVT, INP-Purpan, UPS, 31027 Toulouse, France.
| | - Catherine Brabet
- Centre de Coopération Internationale en Recherche Agronomique pour le Développement (CIRAD)-Département PERSYST-UMR QualiSud, 34398 Montpellier, France.
| | - Olivier Puel
- Toxalim (Research Centre in Food Toxicology), Université de Toulouse, INRA, ENVT, INP-Purpan, UPS, 31027 Toulouse, France.
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Paulussen C, Hallsworth JE, Álvarez‐Pérez S, Nierman WC, Hamill PG, Blain D, Rediers H, Lievens B. Ecology of aspergillosis: insights into the pathogenic potency of Aspergillus fumigatus and some other Aspergillus species. Microb Biotechnol 2017; 10:296-322. [PMID: 27273822 PMCID: PMC5328810 DOI: 10.1111/1751-7915.12367] [Citation(s) in RCA: 179] [Impact Index Per Article: 25.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2015] [Revised: 04/08/2016] [Accepted: 04/18/2016] [Indexed: 01/26/2023] Open
Abstract
Fungi of the genus Aspergillus are widespread in the environment. Some Aspergillus species, most commonly Aspergillus fumigatus, may lead to a variety of allergic reactions and life-threatening systemic infections in humans. Invasive aspergillosis occurs primarily in patients with severe immunodeficiency, and has dramatically increased in recent years. There are several factors at play that contribute to aspergillosis, including both fungus and host-related factors such as strain virulence and host pulmonary structure/immune status, respectively. The environmental tenacity of Aspergilllus, its dominance in diverse microbial communities/habitats, and its ability to navigate the ecophysiological and biophysical challenges of host infection are attributable, in large part, to a robust stress-tolerance biology and exceptional capacity to generate cell-available energy. Aspects of its stress metabolism, ecology, interactions with diverse animal hosts, clinical presentations and treatment regimens have been well-studied over the past years. Here, we synthesize these findings in relation to the way in which some Aspergillus species have become successful opportunistic pathogens of human- and other animal hosts. We focus on the biophysical capabilities of Aspergillus pathogens, key aspects of their ecophysiology and the flexibility to undergo a sexual cycle or form cryptic species. Additionally, recent advances in diagnosis of the disease are discussed as well as implications in relation to questions that have yet to be resolved.
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Affiliation(s)
- Caroline Paulussen
- Laboratory for Process Microbial Ecology and Bioinspirational Management (PME&BIM)Department of Microbial and Molecular Systems (M2S)KU LeuvenCampus De NayerSint‐Katelijne‐WaverB‐2860Belgium
| | - John E. Hallsworth
- Institute for Global Food SecuritySchool of Biological SciencesMedical Biology CentreQueen's University BelfastBelfastBT9 7BLUK
| | - Sergio Álvarez‐Pérez
- Faculty of Veterinary MedicineDepartment of Animal HealthUniversidad Complutense de MadridMadridE‐28040Spain
| | | | - Philip G. Hamill
- Institute for Global Food SecuritySchool of Biological SciencesMedical Biology CentreQueen's University BelfastBelfastBT9 7BLUK
| | - David Blain
- Institute for Global Food SecuritySchool of Biological SciencesMedical Biology CentreQueen's University BelfastBelfastBT9 7BLUK
| | - Hans Rediers
- Laboratory for Process Microbial Ecology and Bioinspirational Management (PME&BIM)Department of Microbial and Molecular Systems (M2S)KU LeuvenCampus De NayerSint‐Katelijne‐WaverB‐2860Belgium
| | - Bart Lievens
- Laboratory for Process Microbial Ecology and Bioinspirational Management (PME&BIM)Department of Microbial and Molecular Systems (M2S)KU LeuvenCampus De NayerSint‐Katelijne‐WaverB‐2860Belgium
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Viaro HP, da Silva JJ, de Souza Ferranti L, Bordini JG, Massi FP, Fungaro MHP. The first report of A. novoparasiticus , A. arachidicola and A. pseudocaelatus in Brazilian corn kernels. Int J Food Microbiol 2017; 243:46-51. [DOI: 10.1016/j.ijfoodmicro.2016.12.002] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2016] [Revised: 11/20/2016] [Accepted: 12/09/2016] [Indexed: 11/26/2022]
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24
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Katsurayama AM, Taniwaki MH. Fungos e aflatoxinas no arroz: ocorrência e significado na saúde do consumidor. BRAZILIAN JOURNAL OF FOOD TECHNOLOGY 2017. [DOI: 10.1590/1981-6723.0617] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Resumo O arroz é um dos cereais mais consumidos no Brasil e no mundo. Devido ao grande impacto do consumo de arroz na população, estudos sobre a qualidade deste produto são de grande importância. É um ótimo substrato para a produção de micotoxinas e, quando os fungos toxigênicos encontram condições de crescer e produzir toxinas, estes as produzem em grandes quantidades. Embora não seja comum a presença de micotoxinas, existem alguns relatos sobre a ocorrência de aflatoxinas e fungos aflatoxigênicos no arroz. O presente artigo é uma revisão sobre os aspectos gerais do arroz, sua produção, ocorrência de fungos, aflatoxinas e micotoxinas no Brasil e no mundo, bem como sobre a redução de aflatoxinas durante o processamento do arroz.
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Abstract
The genus Aspergillus is among the most abundant and widely distributed organism on earth, and at the moment comprises 339 known species. It is one of the most important economically fungal genus and the biotechnological use of Aspergillus species is related to production of soy sauce, of different hydrolytic enzymes (amylases, lipases) and organic acid (citric acid, gluconic acid), as well as biologically active metabolites such as lovastatin. Although they are not considered to be major cause of plant diseases, Aspergillus species are responsible for several disorders in various plants and plant products, especially as opportunistic storage moulds. The notable consequence of their presence is contamination of foods and feeds by mycotoxins, among which the most important are aflatoxins, ochratoxin A, and, at a less extent, fumonisins. Aflatoxins B1, B2, G1, G2 are the most toxic and carcinogenic mycotoxins, due to their extreme hepatocarcinogenicity; ochratoxin A is a potent nephrotoxin, it is also carcinogenic, teratogenic, and immunotoxic in rats and possibly in humans; fumonisins are hepatotoxic and nephrotoxic with potential carcinogenic effects on rat and mice. In this chapter we summarize the main aspects of morphology, ecology, epidemiology, and toxigenicity of Aspergillus foodborne pathogens which belong to sections Flavi, Circumdati, and Nigri, occurring in several agricultural products and responsible of aflatoxin, ochratoxin A, and fumonisins contamination of food and feed.
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Affiliation(s)
- Giancarlo Perrone
- Institute of Sciences of Food Production (ISPA), National Research Council (CNR), Via Amendola 122/O, Bari, 70126, Italy.
| | - Antonia Gallo
- Institute of Sciences of Food Production (ISPA), National Research Council (CNR), via Provinciale Lecce-Monteroni, Lecce, 73100, Italy
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26
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Abstract
This article lists proposed new or revised species names and classification changes associated with fungi of medical importance for the years 2012 through 2015. While many of the revised names listed have been widely adopted without further discussion, some may take longer to achieve more general usage.
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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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Houbraken J, de Vries RP, Samson RA. Modern taxonomy of biotechnologically important Aspergillus and Penicillium species. ADVANCES IN APPLIED MICROBIOLOGY 2014; 86:199-249. [PMID: 24377856 DOI: 10.1016/b978-0-12-800262-9.00004-4] [Citation(s) in RCA: 130] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Taxonomy is a dynamic discipline and name changes of fungi with biotechnological, industrial, or medical importance are often difficult to understand for researchers in the applied field. Species belonging to the genera Aspergillus and Penicillium are commonly used or isolated, and inadequate taxonomy or uncertain nomenclature of these genera can therefore lead to tremendous confusion. Misidentification of strains used in biotechnology can be traced back to (1) recent changes in nomenclature, (2) new taxonomic insights, including description of new species, and/or (3) incorrect identifications. Changes in the recent published International Code of Nomenclature for Algae, Fungi and Plants will lead to numerous name changes of existing Aspergillus and Penicillium species and an overview of the current names of biotechnological important species is given. Furthermore, in (biotechnological) literature old and invalid names are still used, such as Aspergillus awamori, A. foetidus, A. kawachii, Talaromyces emersonii, Acremonium cellulolyticus, and Penicillium funiculosum. An overview of these and other species with their correct names is presented. Furthermore, the biotechnologically important species Talaromyces thermophilus is here combined in Thermomyces as Th. dupontii. The importance of Aspergillus, Penicillium, and related genera is also illustrated by the high number of undertaken genome sequencing projects. A number of these strains are incorrectly identified or atypical strains are selected for these projects. Recommendations for correct strain selection are given here. Phylogenetic analysis shows a close relationship between the genome-sequenced strains of Aspergillus, Penicillium, and Monascus. Talaromyces stipitatus and T. marneffei (syn. Penicillium marneffei) are closely related to Thermomyces lanuginosus and Th. dupontii (syn. Talaromyces thermophilus), and these species appear to be distantly related to Aspergillus and Penicillium. In the last part of this review, an overview of heterothallic reproduction in Aspergillus and Penicillium is given. The new insights in the taxonomy of Aspergillus, Penicillium, and related genera will help to interpret the results generated with comparative genomics studies or other studies dealing with evolution of, for example, enzymes, mating-type loci, virulence genes, and secondary metabolite biosynthetic gene clusters.
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Affiliation(s)
- Jos Houbraken
- CBS-KNAW Fungal Biodiversity Centre, Utrecht, The Netherlands.
| | | | - Robert A Samson
- CBS-KNAW Fungal Biodiversity Centre, Utrecht, The Netherlands
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Iamanaka BT, Nakano F, Lemes DP, Ferranti LS, Taniwaki MH. Aflatoxin evaluation in ready-to-eat brazil nuts using reversed-phase liquid chromatography and post-column derivatisation. Food Addit Contam Part A Chem Anal Control Expo Risk Assess 2014; 31:917-23. [PMID: 24552594 DOI: 10.1080/19440049.2014.895857] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
Abstract
A high-performance liquid chromatography-fluorescence (HPLC-FD) method for aflatoxin quantification in brazil nuts was developed. Samples of brazil nuts collected in Brazilian markets were extracted with methanol:water and cleaned using an immunoaffinity column. Aflatoxins were eluted with methanol and a post-column derivatisation was performed with bromine, using a Kobra Cell system. The optimised method for total aflatoxins was sensitive, with detection and quantification limits of 0.05 and 0.25 µg kg⁻¹, respectively. The method was accurate, with recovery values of 87.6%; 85.3% and 85.0% for 0.5, 5.0 and 14.6 µg kg⁻¹ spiked levels, respectively. It was shown that the method was applicable to brazil nuts. From a total of 95 brazil nut samples analysed from 21 São Paulo supermarket samples and 51 Manaus and 23 Belém street markets samples, 37.9% showed detectable levels of aflatoxins and three exceeded the recommended Codex Alimentarius limit of 10 µg kg⁻¹ for ready-to-eat brazil nuts.
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Adjovi YCS, Bailly S, Gnonlonfin BJG, Tadrist S, Querin A, Sanni A, Oswald IP, Puel O, Bailly JD. Analysis of the contrast between natural occurrence of toxigenic Aspergilli of the Flavi section and aflatoxin B1 in cassava. Food Microbiol 2013; 38:151-9. [PMID: 24290638 DOI: 10.1016/j.fm.2013.08.005] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2013] [Revised: 07/31/2013] [Accepted: 08/14/2013] [Indexed: 12/29/2022]
Abstract
Aflatoxin B1 (AFB1) is a carcinogenic mycotoxin produced by Aspergilli of the section Flavi that may contaminate food, in the field or during storage. Cassava represents an important staple food in sub-Saharan Africa. The analysis of aflatoxigenic fungi in 36 cassava samples obtained from producers in Benin indicated that 40% were contaminated by Aspergilli of the section Flavi. Upon morphological and molecular characterization of the 20 isolates, 16 belonged to Aspergillus flavus, 2 to Aspergillus parvisclerotigenus and 2 to Aspergillus novoparasiticus. This is the first time that this latter species is isolated from food. Although most of these isolates were toxigenic on synthetic media, no AFB1 contamination was observed in these cassava samples. In order to determine the action of cassava on AFB1 synthesis, a highly toxigenic strain of A. flavus, was inoculated onto fresh cassava and despite a rapid development, no AFB1 was produced. The anti-aflatoxin property was observed with cassava from different geographical origins and on other aflatoxigenic strains of the section Flavi, but it was lost after heating, sun drying and freezing. Our data suggest that fresh cassava is safe regarding AFB1 contamination, however, processing may alter its ability to block toxinogenesis leading to secondary contamination.
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Affiliation(s)
- Y C S Adjovi
- INRA, UMR1331, Toxalim, Research Centre in Food Toxicology, F-31027 Toulouse, France; Université de Toulouse III, INP, Toxalim, F-31076 Toulouse, France; Laboratoire de Biochimie et de Biologie Moléculaire, 04 P.O. Box 0320, Cotonou, Benin
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31
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In vitro antifungal susceptibility of clinically relevant species belonging to Aspergillus section Flavi. Antimicrob Agents Chemother 2013; 57:1944-7. [PMID: 23335742 DOI: 10.1128/aac.01902-12] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The in vitro antifungal susceptibility of 77 isolates belonging to different clinically relevant species of Aspergillus section Flavi, including those of different phylogenetic clades of A. flavus, was tested for nine antifungal agents using a microdilution reference method (CLSI, M38-A2). Terbinafine and the echinocandins demonstrated lower MICs/MECs for all species evaluated, followed by posaconazole. Amphotericin B showed MICs ≥ 2 μg/ml for 38 (49.4%) of the 77 isolates tested.
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Santos DWCL, Padovan ACB, Melo ASA, Gonçalves SS, Azevedo VR, Ogawa MM, Freitas TVS, Colombo AL. Molecular identification of melanised non-sporulating moulds: a useful tool for studying the epidemiology of phaeohyphomycosis. Mycopathologia 2013; 175:445-54. [PMID: 23288581 DOI: 10.1007/s11046-012-9608-x] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2012] [Accepted: 12/11/2012] [Indexed: 10/27/2022]
Abstract
Subcutaneous infections caused by melanised fungi have been increasingly reported among transplant patients, and these infections have the potential for blood and visceral dissemination. Some moulds, such as Mycelia sterilia, cannot grow and sporulate on different media, making their identification impossible by conventional methods. The fast and accurate identification of melanised fungi at the species level is important because species may have tropism to different organs and different susceptibilities to antifungal agents. Molecular tools have been reported to be helpful for the species identification of non-sporulating moulds. Our goal was to identify the species of M. sterilia isolates obtained from clinical samples of transplant patients using sequences of ITS and the D1/D2 regions of rDNA. Clinical samples were obtained from eight kidney transplant recipients who developed subcutaneous fungal infections. The diagnosis was confirmed by histopathology and conventional culture. Histopathology showed septated, melanised hyphae, and the cultures identified non-sporulating fungi. Therefore, the DNA from the M. sterilia isolates was subjected to PCR amplification and sequencing of the ITS and D1/D2 regions. Genus/species identification was obtained by comparison with gene banks. We obtained the following identifications: Alternaria sp. (2), Cochliobolus lunatus/Curvularia lunata (2), Cochliobolus hawaiiensis/Bipolaris hawaiiensis (1), Ochroconis sp. (1), Medicocopsis romeroi/Pyrenochaeta romeroi (1) and Nigrograna mackinnonii/Pyrenochaeta mackinnonii (1).
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Affiliation(s)
- Daniel W C L Santos
- Special Mycology Laboratory-LEMI, Department of Medicine, Federal University of São Paulo, São Paulo, SP, Brazil
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de Carvalho Parahym AMR, da Silva CM, Domingos IDF, Gonçalves SS, de Melo Rodrigues M, de Morais VLL, Neves RP. Pulmonary infection due to Pseudozyma aphidis in a patient with burkitt lymphoma: first case report. Diagn Microbiol Infect Dis 2013. [DOI: 10.1016/j.diagmicrobio.2012.09.010] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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Gonçalves SS, Cano JF, Stchigel AM, Melo AS, Godoy-Martinez PC, Correa B, Guarro J. Molecular phylogeny and phenotypic variability of clinical and environmental strains of Aspergillus flavus. Fungal Biol 2012; 116:1146-55. [PMID: 23153805 DOI: 10.1016/j.funbio.2012.08.006] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2012] [Revised: 08/13/2012] [Accepted: 08/27/2012] [Indexed: 01/07/2023]
Abstract
Aspergillus flavus is the second most common cause of aspergillosis infection in immunocompromised patients and is responsible for the production of aflatoxins. Little is known about the population structure of A. flavus, although recent molecular and phenotypic data seem to demonstrate that different genetic lineages exist within this species. The aim of this study was to carry out a morphological, physiological, and molecular analysis of a set of clinical and environmental isolates to determine whether this variability is due to species divergence or intraspecific diversity, and to assess whether the clinical isolates form a separate group. The amdS and omtA genes were more phylogenetically informative than the other tested genes and their combined analysis inferred three main clades, with no clear distinction between clinical and environmental isolates. No important morphological and physiological differences were found between the members of the different clades, with the exception of the assimilation of d-glucosamine, which differentiates the members of the clade II from the others.
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Affiliation(s)
- Sarah S Gonçalves
- Department of Medicine, Division of Infectious Diseases, Federal University of São Paulo, Brazil
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Accurate identification of Candida parapsilosis (sensu lato) by use of mitochondrial DNA and real-time PCR. J Clin Microbiol 2012; 50:2310-4. [PMID: 22535986 DOI: 10.1128/jcm.00303-12] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023] Open
Abstract
Candida parapsilosis is the Candida species isolated the second most frequently from blood cultures in South America and some European countries, such as Spain. Since 2005, this species has been considered a complex of 3 closely related species: C. parapsilosis, Candida metapsilosis, and Candida orthopsilosis. Here, we describe a real-time TaqMan-MGB PCR assay, using mitochondrial DNA (mtDNA) as the target, which readily distinguishes these 3 species. We first used comparative genomics to locate syntenic regions between these 3 mitochondrial genomes and then selected NADH5 as the target for the real-time PCR assay. Probes were designed to include a combination of different single-nucleotide polymorphisms that are able to differentiate each species within the C. parapsilosis complex. This new methodology was first tested using mtDNA and then genomic DNA from 4 reference and 5 clinical strains. For assay validation, a total of 96 clinical isolates and 4 American Type Culture Collection (ATCC) isolates previously identified by internal transcribed spacer (ITS) ribosomal DNA (rDNA) sequencing were tested. Real-time PCR using genomic DNA was able to differentiate the 3 species with 100% accuracy. No amplification was observed when DNA from other species was used as the template. We observed 100% congruence with ITS rDNA sequencing identification, including for 30 strains used in blind testing. This novel method allows a quick and accurate intracomplex identification of C. parapsilosis and saves time compared with sequencing, which so far has been considered the "gold standard" for Candida yeast identification. In addition, this assay provides a useful tool for epidemiological and clinical studies of these emergent species.
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36
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Soares C, Rodrigues P, Peterson SW, Lima N, Venâncio A. Three new species of Aspergillus section Flavi isolated from almonds and maize in Portugal. Mycologia 2011; 104:682-97. [PMID: 22123651 DOI: 10.3852/11-088] [Citation(s) in RCA: 51] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
Three new aflatoxin-producing species belonging to Aspergillus section Flavi are described. They are Aspergillus mottae, A. sergii and A. transmontanensis. These species were isolated from Portuguese almonds and maize. An investigation examined morphology, extrolite production and DNA sequence data to characterize these isolates and describe the new species. Phylogenetic analysis showed that A. transmontanensis and A. sergii form a clade with A. parasiticus whereas A. mottae shares a most recent common ancestor with the combined A. flavus and A. parasiticus clade.
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Affiliation(s)
- Célia Soares
- University of Minho, Campus Gualtar, Braga, Portugal
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