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Ahmad MM, Qamar F, Saifi M, Abdin MZ. Natural inhibitors: A sustainable way to combat aflatoxins. Front Microbiol 2022; 13:993834. [PMID: 36569081 PMCID: PMC9773886 DOI: 10.3389/fmicb.2022.993834] [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: 07/14/2022] [Accepted: 10/31/2022] [Indexed: 12/13/2022] Open
Abstract
Among a few hundred mycotoxins, aflatoxins had always posed a major threat to the world. Apart from A. flavus, A. parasiticus, and A. nomius of Aspergillus genus, which are most toxin-producing strains, several fungal bodies including Fusarium, Penicillium, and Alternaria that can biosynthesis aflatoxins. Basically, there are four different types of aflatoxins (Aflatoxin B1 (AFB1), Aflatoxin B2 (AFB2), Aflatoxin G1 (AFG1), Aflatoxin G2 (AFG2)) are produced as secondary metabolites. There are certainly other types of aflatoxins found but they are the by-products of these toxins. The fungal agents generally infect the food crops during harvesting, storing, and/or transporting; making a heavy post-harvest as well as economic loss in both developed and developing countries. And while ingesting the crop products, these toxins get into the dietary system causing aflatoxicosis, liver cirrhosis, etc. Therefore, it is imperative to search for certain ways to control the spread of infections and/or production of these toxins which may also not harm the crop harvest. In this review, we are going to discuss some sustainable methods that can effectively control the spread of infection and inhibit the biosynthesis of aflatoxins.
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Affiliation(s)
- Malik M. Ahmad
- Department of Agriculture, Integral Institute of Agricultural Science and Technology (IIAST), Integral University, Lucknow, India
| | - Firdaus Qamar
- CTPD, Department of Biotechnology, School of Chemical and Life Sciences, New Delhi, India
| | - Monica Saifi
- CTPD, Department of Biotechnology, School of Chemical and Life Sciences, New Delhi, India
| | - Malik Zainul Abdin
- CTPD, Department of Biotechnology, School of Chemical and Life Sciences, New Delhi, India,*Correspondence: Malik Zainul Abdin,
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Evans DA, Beiger JJ, Burch JD, Fuller PH, Glorius F, Kattnig E, Thaisrivongs DA, Trenkle WC, Young JM, Zhang J. Total Synthesis of Aflastatin A. J Am Chem Soc 2022; 144:19953-19972. [PMID: 36269121 DOI: 10.1021/jacs.2c08244] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The total syntheses of aflastatin A and its C3-C48 degradation fragment (6a, R = H) have been accomplished. The syntheses feature several complex diastereoselective fragment couplings, including a Felkin-selective trityl-catalyzed Mukaiyama aldol reaction, a chelate-controlled aldol reaction involving soft enolization with magnesium, and an anti-Felkin-selective boron-mediated oxygenated aldol reaction. Careful comparison of the spectroscopic data for the synthetic C3-C48 degradation fragment to that reported by the isolation group revealed a structural misassignment in the lactol region of the naturally derived degradation product. Ultimately, the data reported for the naturally derived aflastatin A C3-C48 degradation lactol (6a, R = H) were attributed to its derivative lactol trideuteriomethyl ether (6c, R = CD3). Additionally, the revised absolute configurations of six stereogenic centers (C8, C9, and C28-C31) were confirmed.
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Affiliation(s)
- David A Evans
- Department of Chemistry and Chemical Biology, Harvard University, Cambridge, Massachusetts 02138, United States
| | - Jason J Beiger
- Department of Chemistry and Chemical Biology, Harvard University, Cambridge, Massachusetts 02138, United States
| | - Jason D Burch
- Department of Chemistry and Chemical Biology, Harvard University, Cambridge, Massachusetts 02138, United States
| | - Peter H Fuller
- Department of Chemistry and Chemical Biology, Harvard University, Cambridge, Massachusetts 02138, United States
| | - Frank Glorius
- Department of Chemistry and Chemical Biology, Harvard University, Cambridge, Massachusetts 02138, United States
| | - Egmont Kattnig
- Department of Chemistry and Chemical Biology, Harvard University, Cambridge, Massachusetts 02138, United States
| | - David A Thaisrivongs
- Department of Chemistry and Chemical Biology, Harvard University, Cambridge, Massachusetts 02138, United States
| | - William C Trenkle
- Department of Chemistry and Chemical Biology, Harvard University, Cambridge, Massachusetts 02138, United States
| | - Joseph M Young
- Department of Chemistry and Chemical Biology, Harvard University, Cambridge, Massachusetts 02138, United States
| | - Jing Zhang
- Department of Chemistry and Chemical Biology, Harvard University, Cambridge, Massachusetts 02138, United States
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Archer M, Xu J. Current Practices for Reference Gene Selection in RT-qPCR of Aspergillus: Outlook and Recommendations for the Future. Genes (Basel) 2021; 12:genes12070960. [PMID: 34202507 PMCID: PMC8307107 DOI: 10.3390/genes12070960] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2021] [Revised: 06/20/2021] [Accepted: 06/21/2021] [Indexed: 12/21/2022] Open
Abstract
Aspergillus is a genus of filamentous fungi with vast geographic and ecological distributions. Species within this genus are clinically, agriculturally and biotechnologically relevant, leading to increasing interest in elucidating gene expression dynamics of key metabolic and physiological processes. Reverse-transcription quantitative Polymerase Chain Reaction (RT-qPCR) is a sensitive and specific method of quantifying gene expression. A crucial step for comparing RT-qPCR results between strains and experimental conditions is normalisation to experimentally validated reference gene(s). In this review, we provide a critical analysis of current reference gene selection and validation practices for RT-qPCR gene expression analyses of Aspergillus. Of 90 primary research articles obtained through our PubMed query, 17 experimentally validated the reference gene(s) used. Twenty reference genes were used across the 90 studies, with beta-tubulin being the most used reference gene, followed by actin, 18S rRNA and glyceraldehyde 3-phosphate dehydrogenase. Sixteen of the 90 studies used multiple reference genes for normalisation. Failing to experimentally validate the stability of reference genes can lead to conflicting results, as was the case for four studies. Overall, our review highlights the need to experimentally validate reference genes in RT-qPCR studies of Aspergillus.
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Affiliation(s)
| | - Jianping Xu
- Correspondence: ; Tel.: +1-905-525-9140 (ext. 27934); Fax: +1-905-522-6066
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Montalbano S, Degola F, Bartoli J, Bisceglie F, Buschini A, Carcelli M, Feretti D, Galati S, Marchi L, Orsoni N, Pelosi G, Pioli M, Restivo FM, Rogolino D, Scaccaglia M, Serra O, Spadola G, Viola GCV, Zerbini I, Zani C. The AFLATOX ® Project: Approaching the Development of New Generation, Natural-Based Compounds for the Containment of the Mycotoxigenic Phytopathogen Aspergillus flavus and Aflatoxin Contamination. Int J Mol Sci 2021; 22:4520. [PMID: 33926042 PMCID: PMC8123576 DOI: 10.3390/ijms22094520] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2021] [Revised: 04/20/2021] [Accepted: 04/22/2021] [Indexed: 12/14/2022] Open
Abstract
The control of the fungal contamination on crops is considered a priority by the sanitary authorities of an increasing number of countries, and this is also due to the fact that the geographic areas interested in mycotoxin outbreaks are widening. Among the different pre- and post-harvest strategies that may be applied to prevent fungal and/or aflatoxin contamination, fungicides still play a prominent role; however, despite of countless efforts, to date the problem of food and feed contamination remains unsolved, since the essential factors that affect aflatoxins production are various and hardly to handle as a whole. In this scenario, the exploitation of bioactive natural sources to obtain new agents presenting novel mechanisms of action may represent a successful strategy to minimize, at the same time, aflatoxin contamination and the use of toxic pesticides. The Aflatox® Project was aimed at the development of new-generation inhibitors of aflatoxigenic Aspergillus spp. proliferation and toxin production, through the modification of naturally occurring molecules: a panel of 177 compounds, belonging to the thiosemicarbazones class, have been synthesized and screened for their antifungal and anti-aflatoxigenic potential. The most effective compounds, selected as the best candidates as aflatoxin containment agents, were also evaluated in terms of cytotoxicity, genotoxicity and epi-genotoxicity to exclude potential harmful effect on the human health, the plants on which fungi grow and the whole ecosystem.
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Affiliation(s)
- Serena Montalbano
- Department of Chemistry, Life Sciences and Environmental Sustainability, University of Parma, Parco Area delle Scienze 11/A, 43124 Parma, PR, Italy; (S.M.); (J.B.); (F.B.); (A.B.); (M.C.); (N.O.); (G.P.); (M.P.); (F.M.R.); (D.R.); (M.S.); (G.S.)
| | - Francesca Degola
- Department of Chemistry, Life Sciences and Environmental Sustainability, University of Parma, Parco Area delle Scienze 11/A, 43124 Parma, PR, Italy; (S.M.); (J.B.); (F.B.); (A.B.); (M.C.); (N.O.); (G.P.); (M.P.); (F.M.R.); (D.R.); (M.S.); (G.S.)
| | - Jennifer Bartoli
- Department of Chemistry, Life Sciences and Environmental Sustainability, University of Parma, Parco Area delle Scienze 11/A, 43124 Parma, PR, Italy; (S.M.); (J.B.); (F.B.); (A.B.); (M.C.); (N.O.); (G.P.); (M.P.); (F.M.R.); (D.R.); (M.S.); (G.S.)
| | - Franco Bisceglie
- Department of Chemistry, Life Sciences and Environmental Sustainability, University of Parma, Parco Area delle Scienze 11/A, 43124 Parma, PR, Italy; (S.M.); (J.B.); (F.B.); (A.B.); (M.C.); (N.O.); (G.P.); (M.P.); (F.M.R.); (D.R.); (M.S.); (G.S.)
| | - Annamaria Buschini
- Department of Chemistry, Life Sciences and Environmental Sustainability, University of Parma, Parco Area delle Scienze 11/A, 43124 Parma, PR, Italy; (S.M.); (J.B.); (F.B.); (A.B.); (M.C.); (N.O.); (G.P.); (M.P.); (F.M.R.); (D.R.); (M.S.); (G.S.)
- Interdepartmental Centre for Molecular and Translational Oncology COMT, University of Parma, 43124 Parma, PR, Italy;
| | - Mauro Carcelli
- Department of Chemistry, Life Sciences and Environmental Sustainability, University of Parma, Parco Area delle Scienze 11/A, 43124 Parma, PR, Italy; (S.M.); (J.B.); (F.B.); (A.B.); (M.C.); (N.O.); (G.P.); (M.P.); (F.M.R.); (D.R.); (M.S.); (G.S.)
| | - Donatella Feretti
- Department of Medical and Surgical Specialties, Radiological Sciences and Public Health, University of Brescia, 11 Viale Europa, 25123 Brescia, BS, Italy; (D.F.); (G.C.V.V.); (I.Z.); (C.Z.)
| | - Serena Galati
- Interdepartmental Centre for Molecular and Translational Oncology COMT, University of Parma, 43124 Parma, PR, Italy;
| | - Laura Marchi
- Department of Medicine and Surgery, Respiratory Disease and Lung Function Unit, University of Parma, Via Gramsci 14, 43125 Parma, PR, Italy;
| | - Nicolò Orsoni
- Department of Chemistry, Life Sciences and Environmental Sustainability, University of Parma, Parco Area delle Scienze 11/A, 43124 Parma, PR, Italy; (S.M.); (J.B.); (F.B.); (A.B.); (M.C.); (N.O.); (G.P.); (M.P.); (F.M.R.); (D.R.); (M.S.); (G.S.)
| | - Giorgio Pelosi
- Department of Chemistry, Life Sciences and Environmental Sustainability, University of Parma, Parco Area delle Scienze 11/A, 43124 Parma, PR, Italy; (S.M.); (J.B.); (F.B.); (A.B.); (M.C.); (N.O.); (G.P.); (M.P.); (F.M.R.); (D.R.); (M.S.); (G.S.)
| | - Marianna Pioli
- Department of Chemistry, Life Sciences and Environmental Sustainability, University of Parma, Parco Area delle Scienze 11/A, 43124 Parma, PR, Italy; (S.M.); (J.B.); (F.B.); (A.B.); (M.C.); (N.O.); (G.P.); (M.P.); (F.M.R.); (D.R.); (M.S.); (G.S.)
| | - Francesco M. Restivo
- Department of Chemistry, Life Sciences and Environmental Sustainability, University of Parma, Parco Area delle Scienze 11/A, 43124 Parma, PR, Italy; (S.M.); (J.B.); (F.B.); (A.B.); (M.C.); (N.O.); (G.P.); (M.P.); (F.M.R.); (D.R.); (M.S.); (G.S.)
| | - Dominga Rogolino
- Department of Chemistry, Life Sciences and Environmental Sustainability, University of Parma, Parco Area delle Scienze 11/A, 43124 Parma, PR, Italy; (S.M.); (J.B.); (F.B.); (A.B.); (M.C.); (N.O.); (G.P.); (M.P.); (F.M.R.); (D.R.); (M.S.); (G.S.)
| | - Mirco Scaccaglia
- Department of Chemistry, Life Sciences and Environmental Sustainability, University of Parma, Parco Area delle Scienze 11/A, 43124 Parma, PR, Italy; (S.M.); (J.B.); (F.B.); (A.B.); (M.C.); (N.O.); (G.P.); (M.P.); (F.M.R.); (D.R.); (M.S.); (G.S.)
| | - Olga Serra
- Medical Oncology and Breast Unit, Department of Medicine and Surgery, University of Parma, Via Gramsci 14, 43125 Parma, PR, Italy;
| | - Giorgio Spadola
- Department of Chemistry, Life Sciences and Environmental Sustainability, University of Parma, Parco Area delle Scienze 11/A, 43124 Parma, PR, Italy; (S.M.); (J.B.); (F.B.); (A.B.); (M.C.); (N.O.); (G.P.); (M.P.); (F.M.R.); (D.R.); (M.S.); (G.S.)
| | - Gaia C. V. Viola
- Department of Medical and Surgical Specialties, Radiological Sciences and Public Health, University of Brescia, 11 Viale Europa, 25123 Brescia, BS, Italy; (D.F.); (G.C.V.V.); (I.Z.); (C.Z.)
| | - Ilaria Zerbini
- Department of Medical and Surgical Specialties, Radiological Sciences and Public Health, University of Brescia, 11 Viale Europa, 25123 Brescia, BS, Italy; (D.F.); (G.C.V.V.); (I.Z.); (C.Z.)
| | - Claudia Zani
- Department of Medical and Surgical Specialties, Radiological Sciences and Public Health, University of Brescia, 11 Viale Europa, 25123 Brescia, BS, Italy; (D.F.); (G.C.V.V.); (I.Z.); (C.Z.)
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Investigating Useful Properties of Four Streptomyces Strains Active against Fusarium graminearum Growth and Deoxynivalenol Production on Wheat Grains by qPCR. Toxins (Basel) 2020; 12:toxins12090560. [PMID: 32878002 PMCID: PMC7551252 DOI: 10.3390/toxins12090560] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2020] [Revised: 08/20/2020] [Accepted: 08/26/2020] [Indexed: 12/12/2022] Open
Abstract
Streptomyces spp. can be exploited as biocontrol agents (BCAs) against plant pathogens such as Fusarium graminearum, the main causal agent of Fusarium head blight (FHB) and against the contamination of grains with deoxynivalenol (DON). In the present research, four Streptomyces strains active against F. graminearum in dual plate assays were characterized for their ability to colonize detached wheat grains in the presence of F. graminearum and to limit DON production. The pathogen and BCA abundance were assessed by a quantitative real-time PCR, while DON production was assessed by HPLC quantification and compared to ergosterol to correlate the toxin production to the amount of fungal mycelium. Fungal growth and mycotoxin production were assessed with both co-inoculation and late inoculation of the BCAs in vitro (three days post-Fusarium inoculation) to test the interaction between the fungus and the bacteria. The level of inhibition of the pathogen and the toxin production were strain-specific. Overall, a higher level of DON inhibition (up to 99%) and a strong reduction in fungal biomass (up to 71%) were achieved when streptomycetes were co-inoculated with the fungus. This research enabled studying the antifungal efficacy of the four Streptomyces strains and monitoring their development in DON-inducing conditions.
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Dallabona C, Pioli M, Spadola G, Orsoni N, Bisceglie F, Lodi T, Pelosi G, Restivo FM, Degola F. Sabotage at the Powerhouse? Unraveling the Molecular Target of 2-Isopropylbenzaldehyde Thiosemicarbazone, a Specific Inhibitor of Aflatoxin Biosynthesis and Sclerotia Development in Aspergillus flavus, Using Yeast as a Model System. Molecules 2019; 24:molecules24162971. [PMID: 31426298 PMCID: PMC6719062 DOI: 10.3390/molecules24162971] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2019] [Revised: 08/11/2019] [Accepted: 08/14/2019] [Indexed: 11/16/2022] Open
Abstract
Amongst the various approaches to contain aflatoxin contamination of feed and food commodities, the use of inhibitors of fungal growth and/or toxin biosynthesis is showing great promise for the implementation or the replacement of conventional pesticide-based strategies. Several inhibition mechanisms were found taking place at different levels in the biology of the aflatoxin-producing fungal species such as Aspergillus flavus: compounds that influence aflatoxin production may block the biosynthetic pathway through the direct control of genes belonging to the aflatoxin gene cluster, or interfere with one or more of the several steps involved in the aflatoxin metabolism upstream. Recent findings pointed to mitochondrial functionality as one of the potential targets of some aflatoxin inhibitors. Additionally, we have recently reported that the effect of a compound belonging to the class of thiosemicarbazones might be related to the energy generation/carbon flow and redox homeostasis control by the fungal cell. Here, we report our investigation about a putative molecular target of the 3-isopropylbenzaldehyde thiosemicarbazone (mHtcum), using the yeast Saccharomyces cerevisiae as model system, to demonstrate how the compound can actually interfere with the mitochondrial respiratory chain.
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Affiliation(s)
- Cristina Dallabona
- Department of Chemistry, Life Sciences and Environmental Sustainability, University of Parma, Parco Area delle Scienze 11/A, 43123 Parma, Italy
| | - Marianna Pioli
- Department of Chemistry, Life Sciences and Environmental Sustainability, University of Parma, Parco Area delle Scienze 11/A, 43123 Parma, Italy
| | - Giorgio Spadola
- Department of Chemistry, Life Sciences and Environmental Sustainability, University of Parma, Parco Area delle Scienze 11/A, 43123 Parma, Italy
| | - Nicolò Orsoni
- Department of Chemistry, Life Sciences and Environmental Sustainability, University of Parma, Parco Area delle Scienze 11/A, 43123 Parma, Italy
| | - Franco Bisceglie
- Department of Chemistry, Life Sciences and Environmental Sustainability, University of Parma, Parco Area delle Scienze 11/A, 43123 Parma, Italy
| | - Tiziana Lodi
- Department of Chemistry, Life Sciences and Environmental Sustainability, University of Parma, Parco Area delle Scienze 11/A, 43123 Parma, Italy
| | - Giorgio Pelosi
- Department of Chemistry, Life Sciences and Environmental Sustainability, University of Parma, Parco Area delle Scienze 11/A, 43123 Parma, Italy
| | - Francesco Maria Restivo
- Department of Chemistry, Life Sciences and Environmental Sustainability, University of Parma, Parco Area delle Scienze 11/A, 43123 Parma, Italy
| | - Francesca Degola
- Department of Chemistry, Life Sciences and Environmental Sustainability, University of Parma, Parco Area delle Scienze 11/A, 43123 Parma, Italy.
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El Sheikha AF. Molecular Detection of Mycotoxigenic Fungi in Foods: The Case for Using PCR-DGGE. FOOD BIOTECHNOL 2019. [DOI: 10.1080/08905436.2018.1547644] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Affiliation(s)
- Aly Farag El Sheikha
- Jiangxi Key Laboratory for Conservation and Utilization of Fungal Resources, Jiangxi Agricultural University, Nanchang, China
- Department of Biology, McMaster University, Hamilton, Ontario, Canada
- Department of Food Science and Technology, Faculty of Agriculture, Minufiya University, Shibin El Kom, Minufiya Government, Egypt
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8
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Identification of Antifungal Targets Based on Computer Modeling. J Fungi (Basel) 2018; 4:jof4030081. [PMID: 29973534 PMCID: PMC6162656 DOI: 10.3390/jof4030081] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2018] [Revised: 06/24/2018] [Accepted: 06/29/2018] [Indexed: 01/07/2023] Open
Abstract
Aspergillus fumigatus is a saprophytic, cosmopolitan fungus that attacks patients with a weak immune system. A rational solution against fungal infection aims to manipulate fungal metabolism or to block enzymes essential for Aspergillus survival. Here we discuss and compare different bioinformatics approaches to analyze possible targeting strategies on fungal-unique pathways. For instance, phylogenetic analysis reveals fungal targets, while domain analysis allows us to spot minor differences in protein composition between the host and fungi. Moreover, protein networks between host and fungi can be systematically compared by looking at orthologs and exploiting information from host⁻pathogen interaction databases. Further data—such as knowledge of a three-dimensional structure, gene expression data, or information from calculated metabolic fluxes—refine the search and rapidly put a focus on the best targets for antimycotics. We analyzed several of the best targets for application to structure-based drug design. Finally, we discuss general advantages and limitations in identification of unique fungal pathways and protein targets when applying bioinformatics tools.
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Structural modification of cuminaldehyde thiosemicarbazone increases inhibition specificity toward aflatoxin biosynthesis and sclerotia development in Aspergillus flavus. Appl Microbiol Biotechnol 2017; 101:6683-6696. [PMID: 28725928 DOI: 10.1007/s00253-017-8426-y] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2017] [Revised: 06/29/2017] [Accepted: 07/02/2017] [Indexed: 01/18/2023]
Abstract
Aspergillus flavus is an opportunistic mold that represents a serious threat for human and animal health due to its ability to synthesize and release, on food and feed commodities, different toxic secondary metabolites. Among them, aflatoxin B1 is one of the most dangerous since it is provided with a strong cancerogenic and mutagenic activity. Controlling fungal contamination on the different crops that may host A. flavus is considered a priority by sanitary authorities of an increasing number of countries due also to the fact that, owing to global temperature increase, the geographic areas that are expected to be prone to experience sudden A. flavus outbreaks are widening. Among the different pre- and post-harvest strategies that may be put forward in order to prevent fungal and/or mycotoxin contamination, fungicides are still considered a prominent weapon. We have here analyzed different structural modifications of a natural-derived compound (cuminaldehyde thiosemicarbazone) for their fungistatic and anti-aflatoxigenic activity. In particular, we have focused our attention on one of the compound that presented a prominent anti-aflatoxin specificity, and performed a set of physiological and molecular analyses, taking also advantage of yeast (Saccharomyces cerevisiae) cell as an experimental model.
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Verheecke C, Liboz T, Anson P, Zhu Y, Mathieu F. Streptomyces-Aspergillus flavus interactions: impact on aflatoxin B accumulation. Food Addit Contam Part A Chem Anal Control Expo Risk Assess 2015; 32:572-6. [PMID: 25632796 DOI: 10.1080/19440049.2014.1003336] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
Abstract
The aim of this work was to investigate the potential of Streptomyces sp. as biocontrol agents against aflatoxins in maize. As such, we assumed that Streptomyces sp. could provide a complementary approach to current biocontrol systems such as Afla-guard(®) and we focused on biocontrol that was able to have an antagonistic contact with A. flavus. A previous study showed that 27 (out of 38) Streptomyces sp. had mutual antagonism in contact with A. flavus. Among these, 16 Streptomyces sp. were able to reduce aflatoxin content to below 17% of the residual concentration. We selected six strains to understand the mechanisms involved in the prevention of aflatoxin accumulation. Thus, in interaction with A. flavus, we monitored by RT-qPCR the gene expression of aflD, aflM, aflP, aflR and aflS. All the Streptomyces sp. were able to reduce aflatoxin concentration (24.0-0.2% residual aflatoxin B1). They all impacted on gene expression, but only S35 and S38 were able to repress expression significantly. Indeed, S35 significantly repressed aflM expression and S38 significantly repressed aflR, aflM and aflP. S6 reduced aflatoxin concentrations (2.3% residual aflatoxin B1) and repressed aflS, aflM and enhanced aflR expression. In addition, the S6 strain (previously identified as the most reducing pure aflatoxin B1) was further tested to determine a potential adsorption mechanism. We did not observe any adsorption phenomenon. In conclusion, this study showed that Streptomyces sp. prevent the production of (aflatoxin gene expression) and decontamination of (aflatoxin B1 reduction) aflatoxins in vitro.
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Affiliation(s)
- C Verheecke
- a Laboratoire de Génie Chimique , Université de Toulouse , Castanet-Tolosan , France
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11
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Tan YY, Hsu WH, Shih TW, Lin CH, Pan TM. Proteomic insight into the effect of ethanol on citrinin biosynthesis pathway in Monascus purpureus NTU 568. Food Res Int 2014; 64:733-742. [DOI: 10.1016/j.foodres.2014.08.004] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2014] [Revised: 07/30/2014] [Accepted: 08/14/2014] [Indexed: 01/07/2023]
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12
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Wang K, Yan PS, Cao LX, Ding QL, Shao C, Zhao TF. Potential of chitinolytic Serratia marcescens strain JPP1 for biological control of Aspergillus parasiticus and aflatoxin. BIOMED RESEARCH INTERNATIONAL 2013; 2013:397142. [PMID: 23865052 PMCID: PMC3705848 DOI: 10.1155/2013/397142] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/26/2013] [Revised: 06/08/2013] [Accepted: 06/09/2013] [Indexed: 11/17/2022]
Abstract
Serratia marcescens strain JPP1 was isolated from peanut hulls in Huai'an city, Jiangsu Province, China. Its potential to inhibit the mycelial growth of Aspergillus parasiticus and the subsequent aflatoxin production was evaluated. The strain JPP1 could produce chitinase to degrade fungal cell walls, which was the main mechanism of strain JPP1 for biocontrol. Scanning electron microscopy of fungi treated with the crude chitinase revealed abnormal morphological changes. While the strain was grown in the peanut hulls-based medium, the chitinase activity reached 7.39 units. RT-PCR analysis showed that the crude chitinase repressed the transcription of genes involved in the aflatoxin gene cluster, such as aflR, aflC (pksL1), and aflO (dmtA) genes. By visual agar plate assay and tip culture method, the strain JPP1 exhibited remarkable inhibitory effect on mycelia growth (antifungal ratio >95%) and subsequent aflatoxin production (antiaflatoxigenic ratio >98%). An in vitro assay with seed coating agent of bacterial suspension showed that strain JPP1 effectively reduced fungal growth and subsequent aflatoxin production on peanut seeds, and its antagonistic effect was superior to the common agricultural fungicide of carbendazim. These characteristics suggest that S. marcescens JPP1 strain could potentially be utilized for the biological control of phytopathogenic fungi and aflatoxin in Chinese peanut main producing areas.
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Affiliation(s)
- Kai Wang
- School of Marine Science and Technology, Harbin Institute of Technology, Weihai 264209, China
| | - Pei-sheng Yan
- School of Marine Science and Technology, Harbin Institute of Technology, Weihai 264209, China
| | - Li-xin Cao
- School of Marine Science and Technology, Harbin Institute of Technology, Weihai 264209, China
| | - Qing-long Ding
- School of Marine Science and Technology, Harbin Institute of Technology, Weihai 264209, China
| | - Chi Shao
- School of Marine Science and Technology, Harbin Institute of Technology, Weihai 264209, China
| | - Teng-fei Zhao
- School of Marine Science and Technology, Harbin Institute of Technology, Weihai 264209, China
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Wang K, Yan PS, Ding QL, Wu QX, Wang ZB, Peng J. Diversity of culturable root-associated/endophytic bacteria and their chitinolytic and aflatoxin inhibition activity of peanut plant in China. World J Microbiol Biotechnol 2012; 29:1-10. [PMID: 23108663 DOI: 10.1007/s11274-012-1135-x] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2012] [Accepted: 07/14/2012] [Indexed: 10/27/2022]
Abstract
A total of 72 isolates of root-associated/endophytic (RAE) bacteria were isolated from peanut plants grown in the main producing areas of 6 provinces in China. The 16S rRNA gene sequences of these isolates were determined and phylogenetic analyses revealed that 72 isolates belonged to the classes Bacilli (49 isolates) and Gammaproteobacteria (23 isolates). The majority of RAE bacteria in Bacilli belonged to 2 genera, Bacillus and Lysinibacillus (48 and 1) while those in Gammaproteobacteria belonged to the genera Enterobacter, Serratia, Stenotrophomonas, and Pseudomonas (7, 11, 3 and 2 isolates, respectively). This is the first report of Lysinibacillus xylanilyticus isolate as biocontrol agent against AFs. All of the selected RAE bacteria showed inhibitory activities against Aspergillus parasiticus (A. parasiticus) growth and/or aflatoxins (AFs) production by visual agar plate assay and tip culture method. Most of the RAE bacteria strains (96 % strains) were determined to have decreased mycelia growth or AFs production levels by >50 % (p < 0.05). Bacterial isolates were further characterized for chitinolytic activity and 22 strains (30 % strains) of identified RAE bacteria degraded colloidal chitin on the chitin medium plate. Ten selected chitinolytic RAE bacteria were tested for antifungal activity on peanuts and most of them significantly decreased mycelial growth and AFs production levels by >90 %. These results showed a wide distribution of biological control bacteria against AFs in Chinese peanut main producing areas and the selected RAE bacteria could potentially be utilized for the biocontrol of toxicogenic fungi.
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Affiliation(s)
- Kai Wang
- School of Municipal & Environmental Engineering, Harbin Institute of Technology, 150090 Harbin, China.
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Jermnak U, Yoshinari T, Sugiyama Y, Tsuyuki R, Nagasawa H, Sakuda S. Isolation of methyl syringate as a specific aflatoxin production inhibitor from the essential oil of Betula alba and aflatoxin production inhibitory activities of its related compounds. Int J Food Microbiol 2011; 153:339-44. [PMID: 22177852 DOI: 10.1016/j.ijfoodmicro.2011.11.023] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2011] [Revised: 11/21/2011] [Accepted: 11/26/2011] [Indexed: 12/14/2022]
Abstract
Methyl syringate was isolated from the essential oil of Betula alba as an aflatoxin production inhibitor. It inhibited aflatoxin production of Aspergillus parasiticus and Aspergillus flavus with IC(50) values of 0.9 and 0.8 mM, respectively, without significantly inhibiting fungal growth. Methyl syringate reduced mRNA levels of genes (aflR, pksA, and omtB) [corrected] encoding proteins required for aflatoxin biosynthesis. Methyl gallate, methyl 3,4,5-trimethoxybenzoate, and methyl 3-O-methylgallate inhibited both aflatoxin production and fungal growth of A. parasiticus and A. flavus. However, their acids and syringic acid did not inhibit aflatoxin production and growth of A. parasiticus significantly, although gallic acid inhibited aflatoxin production of A. flavus with selectivity. The 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging activity of methyl syringate was much weaker than that of gallic acid. These results showed that methyl syringate has a unique inhibitory activity toward aflatoxin production with a different mode of action from that of gallic acid.
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Affiliation(s)
- Usuma Jermnak
- Department of Applied Biological Chemistry, The University of Tokyo, 1-1-1 Yayoi, Bunkyo-ku, Tokyo 113-8657, Japan
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Roze LV, Chanda A, Laivenieks M, Beaudry RM, Artymovich KA, Koptina AV, Awad DW, Valeeva D, Jones AD, Linz JE. Volatile profiling reveals intracellular metabolic changes in Aspergillus parasiticus: veA regulates branched chain amino acid and ethanol metabolism. BMC BIOCHEMISTRY 2010; 11:33. [PMID: 20735852 PMCID: PMC2939540 DOI: 10.1186/1471-2091-11-33] [Citation(s) in RCA: 52] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/02/2010] [Accepted: 08/24/2010] [Indexed: 01/17/2023]
Abstract
Background Filamentous fungi in the genus Aspergillus produce a variety of natural products, including aflatoxin, the most potent naturally occurring carcinogen known. Aflatoxin biosynthesis, one of the most highly characterized secondary metabolic pathways, offers a model system to study secondary metabolism in eukaryotes. To control or customize biosynthesis of natural products we must understand how secondary metabolism integrates into the overall cellular metabolic network. By applying a metabolomics approach we analyzed volatile compounds synthesized by Aspergillus parasiticus in an attempt to define the association of secondary metabolism with other metabolic and cellular processes. Results Volatile compounds were examined using solid phase microextraction - gas chromatography/mass spectrometry. In the wild type strain Aspergillus parasiticus SU-1, the largest group of volatiles included compounds derived from catabolism of branched chain amino acids (leucine, isoleucine, and valine); we also identified alcohols, esters, aldehydes, and lipid-derived volatiles. The number and quantity of the volatiles produced depended on media composition, time of incubation, and light-dark status. A block in aflatoxin biosynthesis or disruption of the global regulator veA affected the volatile profile. In addition to its multiple functions in secondary metabolism and development, VeA negatively regulated catabolism of branched chain amino acids and synthesis of ethanol at the transcriptional level thus playing a role in controlling carbon flow within the cell. Finally, we demonstrated that volatiles generated by a veA disruption mutant are part of the complex regulatory machinery that mediates the effects of VeA on asexual conidiation and sclerotia formation. Conclusions 1) Volatile profiling provides a rapid, effective, and powerful approach to identify changes in intracellular metabolic networks in filamentous fungi. 2) VeA coordinates the biosynthesis of secondary metabolites with catabolism of branched chain amino acids, alcohol biosynthesis, and β-oxidation of fatty acids. 3) Intracellular chemical development in A. parasiticus is linked to morphological development. 4) Understanding carbon flow through secondary metabolic pathways and catabolism of branched chain amino acids is essential for controlling and customizing production of natural products.
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Affiliation(s)
- Ludmila V Roze
- Department of Food Science and Human Nutrition, Michigan State University, East Lansing, MI, USA.
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Inhibitory activity of blasticidin A, a strong aflatoxin production inhibitor, on protein synthesis of yeast: selective inhibition of aflatoxin production by protein synthesis inhibitors. J Antibiot (Tokyo) 2010; 63:309-14. [PMID: 20414321 DOI: 10.1038/ja.2010.36] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Blasticidin A (BcA), an antibiotic produced by Streptomyces, inhibits aflatoxin production without strong growth inhibition toward aflatoxin-producing fungi. During the course of our study on the mode of action of BcA by two-dimensional differential gel electrophoresis (2D-DIGE), we found a decrease in the abundances of ribosomal proteins in Saccharomyces cerevisiae after exposure to BcA. This phenomenon was also observed by treatment with blasticidin S (BcS) or cycloheximide. BcA inhibited protein synthesis in a galactose-induced expression system in S. cerevisiae similar to BcS and cycloheximide. BcS, but not cycloheximide, inhibited aflatoxin production in Aspergillus parasiticus without inhibition of fungal growth, similar to BcA. A decrease in the abundances of aflatoxin biosynthetic enzymes was observed in 2D-DIGE experiments with Aspergillus flavus after exposure to BcA or BcS. These results suggested that protein synthesis inhibitors are useful to control aflatoxin production.
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Holmes RA, Boston RS, Payne GA. Diverse inhibitors of aflatoxin biosynthesis. Appl Microbiol Biotechnol 2008; 78:559-72. [DOI: 10.1007/s00253-008-1362-0] [Citation(s) in RCA: 90] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2007] [Revised: 01/09/2008] [Accepted: 01/10/2008] [Indexed: 10/22/2022]
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Yoshinari T, Akiyama T, Nakamura K, Kondo T, Takahashi Y, Muraoka Y, Nonomura Y, Nagasawa H, Sakuda S. Dioctatin A is a strong inhibitor of aflatoxin production by Aspergillus parasiticus. MICROBIOLOGY-SGM 2007; 153:2774-2780. [PMID: 17660441 DOI: 10.1099/mic.0.2006/005629-0] [Citation(s) in RCA: 56] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
Dioctatin A (DotA), a metabolite of Streptomyces, is known to be an inhibitor of human dipeptidyl aminopeptidase II. Here, it was found that DotA strongly inhibited aflatoxin production by Aspergillus parasiticus, with an IC50 value of 4.0 microM. The mycelial growth of the fungus was not affected by the addition of DotA at a concentration of 50 microM, but inhibition of conidiation was observed at the same concentration. DotA inhibited production of norsolorinic acid, an early biosynthetic intermediate of aflatoxin, and it strongly reduced the mRNA levels of genes encoding aflatoxin biosynthetic enzymes, and significantly decreased the mRNA level of aflR, which encodes a key regulatory protein for aflatoxin biosynthesis. In addition to these genes, the mRNA level of brlA, which encodes a conidiation-specific transcription factor, was also reduced by the addition of DotA. It was also found that DotA dramatically enhanced kojic acid production by the fungus. Furthermore, DotA inhibited production of sterigmatocystin, which is a toxic aflatoxin biosynthetic intermediate, and it also inhibited conidiation in Aspergillus nidulans. These results indicate that DotA has pleiotropic effects on regulatory mechanisms of fungal secondary metabolite production and differentiation, leading to inhibition of aflatoxin production.
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Affiliation(s)
- Tomoya Yoshinari
- Department of Applied Biological Chemistry, The University of Tokyo, Bunkyo-ku, Tokyo 113-8657, Japan
| | - Tetsuo Akiyama
- Microbial Chemistry Research Center, 3-14-23 Kamiosaki, Shinagawa-ku, Tokyo 141-0021, Japan
| | - Keita Nakamura
- Department of Applied Biological Chemistry, The University of Tokyo, Bunkyo-ku, Tokyo 113-8657, Japan
| | - Tatsuhiko Kondo
- Department of Applied Bioscience, Nagoya University, Chikusa-ku, Nagoya 464-8601, Japan
| | - Yoshikazu Takahashi
- Microbial Chemistry Research Center, 3-14-23 Kamiosaki, Shinagawa-ku, Tokyo 141-0021, Japan
| | - Yasuhiko Muraoka
- Microbial Chemistry Research Center, 3-14-23 Kamiosaki, Shinagawa-ku, Tokyo 141-0021, Japan
| | - Yoshiaki Nonomura
- Microbial Chemistry Research Center, 3-14-23 Kamiosaki, Shinagawa-ku, Tokyo 141-0021, Japan
| | - Hiromichi Nagasawa
- Department of Applied Biological Chemistry, The University of Tokyo, Bunkyo-ku, Tokyo 113-8657, Japan
| | - Shohei Sakuda
- Department of Applied Biological Chemistry, The University of Tokyo, Bunkyo-ku, Tokyo 113-8657, Japan
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Ghorbanian M, Razzaghi-Abyaneh M, Allameh A, Shams-Ghahfarokhi M, Qorbani M. Study on the effect of neem (Azadirachta indica A. juss) leaf extract on the growth of Aspergillus parasiticus and production of aflatoxin by it at different incubation times. Mycoses 2007; 51:35-9. [DOI: 10.1111/j.1439-0507.2007.01440.x] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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Sakuda S, Matsumori N, Furihata K, Nagasawa H. Assignment of the absolute configuration of blasticidin A and revision of that of aflastatin A. Tetrahedron Lett 2007. [DOI: 10.1016/j.tetlet.2007.02.024] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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Palumbo JD, Baker JL, Mahoney NE. Isolation of bacterial antagonists of Aspergillus flavus from almonds. MICROBIAL ECOLOGY 2006; 52:45-52. [PMID: 16767519 DOI: 10.1007/s00248-006-9096-y] [Citation(s) in RCA: 44] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/12/2006] [Revised: 04/12/2006] [Accepted: 04/17/2006] [Indexed: 05/10/2023]
Abstract
Bacteria were isolated from California almond orchard samples to evaluate their potential antifungal activity against aflatoxin-producing Aspergillus flavus. Fungal populations from the same samples were examined to determine the incidence of aflatoxigenic Aspergillus species. Antagonistic activities of the isolated bacterial strains were screened against a nonaflatoxigenic nor mutant of A. flavus, which accumulates the pigmented aflatoxin precursor norsolorinic acid (NOR) under conditions conducive to aflatoxin production. Using solid and liquid media in coculture assays, 171 bacteria isolated from almond flowers, immature nut fruits, and mature nut fruits showed inhibition of A. flavus growth and/or inhibition of NOR accumulation. Bacterial isolates were further characterized for production of extracellular enzymes capable of hydrolyzing chitin or yeast cell walls. Molecular and physiological identification of the bacterial strains indicated that the predominant genera isolated were Bacillus, Pseudomonas, Ralstonia, and Burkholderia, as well as several plant-associated enteric and nonenteric bacteria. A set of 20 isolates was selected for further study based on their species identification, antifungal phenotypes, and extracellular enzyme production. Quantitative assays using these isolates in liquid coculture with a wild-type, aflatoxin-producing A. flavus strain showed that a number of strains completely inhibited fungal growth in three different media. These results indicate the potential for development of bacterial antagonists as biological control agents against aflatoxigenic aspergilli on almonds.
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Affiliation(s)
- Jeffrey D Palumbo
- Plant Mycotoxin Research Unit, Western Regional Research Center, Agricultural Research Service, U.S. Department of Agriculture, 800 Buchanan St., Albany, CA 94710, USA.
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Evans DA, Trenkle WC, Zhang J, Burch JD. Synthesis and Confirmation of the Absolute Stereochemistry of the (−)-Aflastatin A C9−C27 Degradation Polyol. Org Lett 2005; 7:3335-8. [PMID: 16018654 DOI: 10.1021/ol051225n] [Citation(s) in RCA: 36] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
[reaction: see text]. The C(8)-C(18) ethyl ketone and C(19)-C(28) aldehyde aflastatin A fragments were synthesized and coupled using a diastereoselective anti aldol reaction. This adduct was successfully converted into the C(9)-C(27) polyol degradation product of (-)-aflastatin A to confirm the relative and absolute stereochemistry of this region of the natural product.
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Affiliation(s)
- David A Evans
- Department of Chemistry and Chemical Biology, Harvard University, Cambridge, Massachusetts 02138, USA.
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Yan PS, Song Y, Sakuno E, Nakajima H, Nakagawa H, Yabe K. Cyclo(L-leucyl-L-prolyl) produced by Achromobacter xylosoxidans inhibits aflatoxin production by Aspergillus parasiticus. Appl Environ Microbiol 2005; 70:7466-73. [PMID: 15574949 PMCID: PMC535151 DOI: 10.1128/aem.70.12.7466-7473.2004] [Citation(s) in RCA: 130] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Aflatoxins are potent carcinogenic and toxic substances that are produced primarily by Aspergillus flavus and Aspergillus parasiticus. We found that a bacterium remarkably inhibited production of norsolorinic acid, a precursor of aflatoxin, by A. parasiticus. This bacterium was identified as Achromobacter xylosoxidans based on its 16S ribosomal DNA sequence and was designated A. xylosoxidans NFRI-A1. A. xylosoxidans strains commonly showed similar inhibition. The inhibitory substance(s) was excreted into the medium and was stable after heat, acid, or alkaline treatment. Although the bacterium appeared to produce several inhibitory substances, we finally succeeded in purifying a major inhibitory substance from the culture medium using Diaion HP20 column chromatography, thin-layer chromatography, and high-performance liquid chromatography. The purified inhibitory substance was identified as cyclo(L-leucyl-L-prolyl) based on physicochemical methods. The 50% inhibitory concentration for aflatoxin production by A. parasiticus SYS-4 (= NRRL2999) was 0.20 mg ml(-1), as determined by the tip culture method. High concentrations (more than 6.0 mg ml(-1)) of cyclo(L-leucyl-L-prolyl) further inhibited fungal growth. Similar inhibitory activities were observed with cyclo(D-leucyl-D-prolyl) and cyclo(L-valyl-L-prolyl), whereas cyclo(D-prolyl-L-leucyl) and cyclo(L-prolyl-D-leucyl) showed weaker activities. Reverse transcription-PCR analyses showed that cyclo(L-leucyl-L-prolyl) repressed transcription of the aflatoxin-related genes aflR, hexB, pksL1, and dmtA. This is the first report of a cyclodipeptide that affects aflatoxin production.
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Affiliation(s)
- Pei-Sheng Yan
- National Food Research Institute, Tsukuba, Ibaraki 305-8642, Japan
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SAKUDA S. Studies on the mode of action of aflastain A, an inhibitor of aflatoxin production. ACTA ACUST UNITED AC 2002. [DOI: 10.2520/myco.52.153] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
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