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Legan AW, Mack BM, Mehl HL, Wissotski M, Ching’anda C, Maxwell LA, Callicott KA. Complete genome of the toxic mold Aspergillus pseudotamarii isolate NRRL 25517 reveals genomic instability of the aflatoxin biosynthesis cluster. G3 (BETHESDA, MD.) 2023; 13:jkad150. [PMID: 37401423 PMCID: PMC10468309 DOI: 10.1093/g3journal/jkad150] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/24/2023] [Revised: 04/24/2023] [Accepted: 06/21/2023] [Indexed: 07/05/2023]
Abstract
Fungi can synthesize a broad array of secondary metabolite chemicals. The genes underpinning their biosynthesis are typically arranged in tightly linked clusters in the genome. For example, ∼25 genes responsible for the biosynthesis of carcinogenic aflatoxins by Aspergillus section Flavi species are grouped in a ∼70 Kb cluster. Assembly fragmentation prevents assessment of the role of structural genomic variation in secondary metabolite evolution in this clade. More comprehensive analyses of secondary metabolite evolution will be possible by working with more complete and accurate genomes of taxonomically diverse Aspergillus species. Here, we combined short- and long-read DNA sequencing to generate a highly contiguous genome of the aflatoxigenic fungus, Aspergillus pseudotamarii (isolate NRRL 25517 = CBS 766.97; scaffold N50 = 5.5 Mb). The nuclear genome is 39.4 Mb, encompassing 12,639 putative protein-encoding genes and 74-97 candidate secondary metabolite biosynthesis gene clusters. The circular mitogenome is 29.7 Kb and contains 14 protein-encoding genes that are highly conserved across the genus. This highly contiguous A. pseudotamarii genome assembly enables comparisons of genomic rearrangements between Aspergillus section Flavi series Kitamyces and series Flavi. Although the aflatoxin biosynthesis gene cluster of A. pseudotamarii is conserved with Aspergillus flavus, the cluster has an inverted orientation relative to the telomere and occurs on a different chromosome.
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Affiliation(s)
- Andrew W Legan
- US Department of Agriculture, Arid Land Agricultural Research Center, Tucson, AZ 85701, USA
| | - Brian M Mack
- US Department of Agriculture, Food and Feed Safety Research Unit, New Orleans, LA 70124, USA
| | - Hillary L Mehl
- US Department of Agriculture, Arid Land Agricultural Research Center, Tucson, AZ 85701, USA
| | - Marina Wissotski
- School of Plant Sciences, University of Arizona, Tucson, AZ 85721, USA
| | - Connel Ching’anda
- School of Plant Sciences, University of Arizona, Tucson, AZ 85721, USA
| | - Lourena A Maxwell
- School of Plant Sciences, University of Arizona, Tucson, AZ 85721, USA
| | - Kenneth A Callicott
- US Department of Agriculture, Arid Land Agricultural Research Center, Tucson, AZ 85701, USA
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2
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Zhuang Y, Sharif Y, Zeng X, Chen S, Chen H, Zhuang C, Deng Y, Ruan M, Chen S, Weijian Z. Molecular cloning and functional characterization of the promoter of a novel Aspergillus flavus inducible gene ( AhOMT1) from peanut. FRONTIERS IN PLANT SCIENCE 2023; 14:1102181. [PMID: 36844094 PMCID: PMC9947529 DOI: 10.3389/fpls.2023.1102181] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 11/18/2022] [Accepted: 01/06/2023] [Indexed: 06/18/2023]
Abstract
Peanut is an important oil and food legume crop grown in more than one hundred countries, but the yield and quality are often impaired by different pathogens and diseases, especially aflatoxins jeopardizing human health and causing global concerns. For better management of aflatoxin contamination, we report the cloning and characterization of a novel A. flavus inducible promoter of the O-methyltransferase gene (AhOMT1) from peanut. The AhOMT1 gene was identified as the highest inducible gene by A. flavus infection through genome-wide microarray analysis and verified by qRT-PCR analysis. AhOMT1 gene was studied in detail, and its promoter, fussed with the GUS gene, was introduced into Arabidopsis to generate homozygous transgenic lines. Expression of GUS gene was studied in transgenic plants under the infection of A. flavus. The analysis of AhOMT1 gene characterized by in silico assay, RNAseq, and qRT-PCR revealed minute expression in different organs and tissues with trace or no response to low temperature, drought, hormones, Ca2+, and bacterial stresses, but highly induced by A. flavus infection. It contains four exons encoding 297 aa predicted to transfer the methyl group of S-adenosyl-L-methionine (SAM). The promoter contains different cis-elements responsible for its expression characteristics. Functional characterization of AhOMT1P in transgenic Arabidopsis plants demonstrated highly inducible behavior only under A. flavus infection. The transgenic plants did not show GUS expression in any tissue(s) without inoculation of A. flavus spores. However, GUS activity increased significantly after inoculation of A. flavus and maintained a high level of expression after 48 hours of infection. These results provided a novel way for future management of peanut aflatoxins contamination through driving resistance genes in A. flavus inducible manner.
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Affiliation(s)
- Yuhui Zhuang
- Center of Legume Plant Genetics and Systems Biology, College of Agriculture, Fujian Agriculture and Forestry University, Fuzhou, China
- College of Life Sciences, Fujian Agriculture and Forestry University, Fuzhou, China
| | - Yasir Sharif
- Center of Legume Plant Genetics and Systems Biology, College of Agriculture, Fujian Agriculture and Forestry University, Fuzhou, China
| | - Xiaohong Zeng
- Center of Legume Plant Genetics and Systems Biology, College of Agriculture, Fujian Agriculture and Forestry University, Fuzhou, China
| | - Suzheng Chen
- Center of Legume Plant Genetics and Systems Biology, College of Agriculture, Fujian Agriculture and Forestry University, Fuzhou, China
| | - Hua Chen
- Center of Legume Plant Genetics and Systems Biology, College of Agriculture, Fujian Agriculture and Forestry University, Fuzhou, China
| | - Chunhong Zhuang
- Center of Legume Plant Genetics and Systems Biology, College of Agriculture, Fujian Agriculture and Forestry University, Fuzhou, China
| | - Ye Deng
- Center of Legume Plant Genetics and Systems Biology, College of Agriculture, Fujian Agriculture and Forestry University, Fuzhou, China
| | | | | | - Zhuang Weijian
- Center of Legume Plant Genetics and Systems Biology, College of Agriculture, Fujian Agriculture and Forestry University, Fuzhou, China
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Singh AK, Dhiman TK, Lakshmi GBVS, Raj R, Jha SK, Solanki PR. Rapid and label-free detection of Aflatoxin-B1 viamicrofluidic electrochemical biosensor based on manganese (III) oxide (Mn 3O 4) synthesized by co-precipitation route at room temperature. NANOTECHNOLOGY 2022; 33:285501. [PMID: 35299158 DOI: 10.1088/1361-6528/ac5ee2] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/10/2021] [Accepted: 03/17/2022] [Indexed: 06/14/2023]
Abstract
Aflatoxin B1 (AFB1) is the most toxic mycotoxin, naturally occurring in food items, and it causes several types of lethal diseases. Therefore, a rapid and convenient detection method for AFB1 is the first step toward overcoming the effect of AFB1. The current work presents the development of an efficient microfluidic electrochemical-based biosensor using tri-manganese tetroxide nanoparticles (Mn3O4nps) for AFB1 detection. The Mn3O4nps were synthesized at room temperature through the co-precipitation route. Its phase purity, structural and morphological studies have been characterized through x-ray diffraction, Raman spectroscopy, energy-dispersive x-ray, Fourier transform infrared spectroscopy and transmission electron microscopy. The mask-less UV-lithography was carried out to fabricate the three-electrode chip and microfluidic channel of the microfluidic electrochemical biosensing system. The designed microfluidic immunosensor (BSA/Ab-AFB1/Mn3O4/ITO) was fabricated using the three-electrode chip, microfluidic channel in poly-dimethyl siloxane. The fabricated sensor exhibited the 3.4μA ml ng-1cm-2sensitivity and had the lowest lower detection limit of 0.295 pg ml-1with the detection range of 1 pg ml-1to 300 ng ml-1. Additionally, the spiked study was also performed with this immunoelectrode and a recovery rate was obtained of 108.2%.
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Affiliation(s)
- Avinash Kumar Singh
- Special Centre for Nanoscience, Jawaharlal Nehru University (JNU), New Delhi-110067, India
- School of Physical Sciences, JNU, New Delhi-110067, India
| | - Tarun Kumar Dhiman
- Special Centre for Nanoscience, Jawaharlal Nehru University (JNU), New Delhi-110067, India
| | - G B V S Lakshmi
- Special Centre for Nanoscience, Jawaharlal Nehru University (JNU), New Delhi-110067, India
| | - Rishi Raj
- Indian Institute of Technology, New Delhi-110067, India
| | | | - Pratima R Solanki
- Special Centre for Nanoscience, Jawaharlal Nehru University (JNU), New Delhi-110067, India
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4
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Mahata PK, Dass RS, Pan A, Muthusamy B. Substantive Morphological Descriptions, Phylogenetic Analysis and Single Nucleotide Polymorphisms of Aspergillus Species From Foeniculum vulgare. Front Microbiol 2022; 13:832320. [PMID: 35250948 PMCID: PMC8894770 DOI: 10.3389/fmicb.2022.832320] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2021] [Accepted: 01/24/2022] [Indexed: 01/10/2023] Open
Abstract
Ascomycetous fungi are found associated with a wide variety of substrates which range from fresh water to marine ecosystems, tropical to temperate forest soils and deserts, throughout the world over. These demystifying fungi exist as endophytes, pathogens and saprobes. They have been studied due to their ability to contaminate foods and feedstuffs, causing an elaboration of mycotoxins. The objectives of the study included extensive analyses of the morphological features of fungi, especially Aspergilli, which have been presented while studying them on specific mycological media. It is also an elaborate compilation of substantive macro- and micro-morphological characterization of different Aspergilli isolated from the spice Foeniculum vulgare used in India and other countries in the world. Further, a first of its kind attempt has been made to study their relative abundance and frequency of occurrence, molecular phylogeny and genetic relatedness to characterize the Aspergilli into specific sections, groups and clades. Single nucleotide polymorphism (SNP) analysis was carried out to evaluate the functional consequences of nucleotide variations, synonymous and non-synonymous mutations in the protein structure. The study resulted in a total of 3,506 Aspergillus isolates, which were obtained from seventy (70) fennel samples, representing 14 Aspergillus species. The two most frequently found species were A. niger and A. flavus with a relative abundance of 32.24 and 11.63%, respectively. The taxonomy and current placements have been reappraised with suggestions and prospects for future research from six sections namely Terrei, Flavi, Fumigati, Nidulantes, Nigri, and Versicolores. In addition, a total number of 27 isolates were studied and deposited at the National Centre for Biotechnology Information (NCBI) and five Aspergillus species have been identified and are being reported for the first time from the fennel seeds, based on partial sequence analysis of the official fungal barcode namely, Internal Transcribed Spacer (ITS) and a functional gene, beta tubulin gene locus, coupled with phenotypic characterization. SNPs for specific DNA regions have been used to identify variants in Aspergilli obtained from Indian fennel seeds for the first time. The need for a polyphasic approach of morphological identification and genetic characterization of Aspergilli from Foeniculum vulgare is addressed and presented here in adequate detail. Our current work makes extensive use of partial beta-tubulin gene sequences analyses to evaluate the association between SNPs in five Aspergillus species sections.
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Affiliation(s)
- Pranab Kumar Mahata
- Fungal Genetics and Mycotoxicology Laboratory, Department of Microbiology, School of Life Sciences, Pondicherry University, Pondicherry, India
| | - Regina Sharmila Dass
- Fungal Genetics and Mycotoxicology Laboratory, Department of Microbiology, School of Life Sciences, Pondicherry University, Pondicherry, India
- *Correspondence: Regina Sharmila Dass,
| | - Archana Pan
- Centre for Bioinformatics, School of Life Sciences, Pondicherry University, Pondicherry, India
| | - Babylakshmi Muthusamy
- Institute of Bioinformatics, International Tech Park, Bengaluru, India
- Manipal Academy of Higher Education, Manipal, India
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Competency of Clove and Cinnamon Essential Oil Fumigation against Toxigenic and Atoxigenic Aspergillus flavus Isolates. JOURNAL OF PURE AND APPLIED MICROBIOLOGY 2021. [DOI: 10.22207/jpam.15.3.23] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Aspergillus flavus is a frequent contaminant of maize grain. We isolated this fungus, determined the colony morphology and species (by internal transcribed spacer sequencing) and measured the aflatoxin content. The selected A. flavus fungi were placed into two groups, toxigenic and atoxigenic; both appeared similar morphologically, except that the atoxigenic group lacked sclerotia. An essential oil fumigation test with clove and cinnamon oils as antifungal products was performed on fungal conidial discs and fungal colonies in Petri plates. Cinnamon oil at 2.5 to 5.0 μL/plate markedly inhibited the mycelial growth from conidial discs of both strains, whereas clove oil showed less activity. The oils had different effects on fungal mycelia. The higher clove fumigation doses of 10.0 to 20.0 μL/plate controlled fungal growth, while cinnamon oil caused less inhibition. Compared with atoxigenic groups, toxigenic A. flavus responded stably. Within abnormal A. flavus hyphae, the essential oils degenerated the hyphal morphology, resulting in exfoliated flakes and shrinkage, which were related to fungal membrane injury and collapse of vacuoles and phialide. The treatments, especially those with cinnamon oil, increased the electroconductivity, which suggested a weak mycelium membrane structure. Moreover, the treatments with essential oils reduced the ergosterol content in mycelia and the aflatoxin accumulation in the culture broth. The fumigations with clove and cinnamon oils inhibited the development of both conidia and colonies of A. flavus in dose-dependent manners.
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Habibi A, Afzali D. Aspergillus Section Flavi from Four Agricultural Products and Association of Mycotoxin and Sclerotia Production with Isolation Source. Curr Microbiol 2021; 78:3674-3685. [PMID: 34398304 DOI: 10.1007/s00284-021-02620-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2021] [Accepted: 07/26/2021] [Indexed: 11/25/2022]
Abstract
Many agricultural products are susceptible to contamination by aflatoxin-producing species from Aspergillus section Flavi. The objectives of this study were to determine the occurrence of Aspergillus section Flavi in four agricultural products, such as pistachio, walnut, hazelnut, and dried fruits, collected from market and retail shops in various areas of Kerman County and obtain information on the relationships between isolation source and ability to produce sclerotia and potential for aflatoxin production. Aspergillus species were identified based on morphological characteristics as well as subsequent sequencing of the parts of the β-tubulin and calmodulin genes. From 207 isolated strains, the following species were identified: A. flavus, A. tamarii A. nomius, A. parasiticus, A. arachidicola, A. caelatus, A. pseudotamarii, and A. leporis. To the best of our knowledge, this is the first report of A. pseudotamarii and A. arachidicola with the potential to produce aflatoxins from dried apricots and hazelnuts, respectively. Sclerotial type was significantly different between isolates from different isolation sources. From 192 tested isolates, 38% were aflatoxin producer from which 5% were scored as strong aflatoxin producers and 33% as average aflatoxin producers. A significant difference in the population of aflatoxin-producing strains across the isolation sources was observed which may reflect host adaptation and thereby different vulnerabilities to aflatoxin-producing species among the examined products.
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Affiliation(s)
- Azadeh Habibi
- Department of Biodiversity, Institute of Science and High Technology and Environmental Sciences, Graduate University of Advanced Technology, Kerman, Iran.
| | - Daryoush Afzali
- Department of Environment, Institute of Science and High Technology and Environmental Sciences, Graduate University of Advanced Technology, Kerman, Iran
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7
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Navale V, Vamkudoth KR, Ajmera S, Dhuri V. Aspergillus derived mycotoxins in food and the environment: Prevalence, detection, and toxicity. Toxicol Rep 2021; 8:1008-1030. [PMID: 34408970 PMCID: PMC8363598 DOI: 10.1016/j.toxrep.2021.04.013] [Citation(s) in RCA: 55] [Impact Index Per Article: 18.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2020] [Revised: 04/20/2021] [Accepted: 04/27/2021] [Indexed: 12/16/2022] Open
Abstract
Aspergillus species are the paramount ubiquitous fungi that contaminate various food substrates and produce biochemicals known as mycotoxins. Aflatoxins (AFTs), ochratoxin A (OTA), patulin (PAT), citrinin (CIT), aflatrem (AT), secalonic acids (SA), cyclopiazonic acid (CPA), terrein (TR), sterigmatocystin (ST) and gliotoxin (GT), and other toxins produced by species of Aspergillus plays a major role in food and human health. Mycotoxins exhibited wide range of toxicity to the humans and animal models even at nanomolar (nM) concentration. Consumption of detrimental mycotoxins adulterated foodstuffs affects human and animal health even trace amounts. Bioaerosols consisting of spores and hyphal fragments are active elicitors of bronchial irritation and allergy, and challenging to the public health. Aspergillus is the furthermost predominant environmental contaminant unswervingly defile lives with a 40-90 % mortality risk in patients with conceded immunity. Genomics, proteomics, transcriptomics, and metabolomics approaches useful for mycotoxins' detection which are expensive. Antibody based detection of toxins chemotypes may result in cross-reactivity and uncertainty. Aptamers (APT) are single stranded DNA (ssDNA/RNA), are specifically binds to the target molecules can be generated by systematic evolution of ligands through exponential enrichment (SELEX). APT are fast, sensitive, simple, in-expensive, and field-deployable rapid point of care (POC) detection of toxins, and a better alternative to antibodies.
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Affiliation(s)
- Vishwambar Navale
- Biochemical Sciences Division, CSIR-National Chemical Laboratory, Pune, 411008, India
- Academy of Scientific and Innovative Research (AcSIR), Anusandhan Bhawan, New Delhi, India
| | - Koteswara Rao Vamkudoth
- Biochemical Sciences Division, CSIR-National Chemical Laboratory, Pune, 411008, India
- Academy of Scientific and Innovative Research (AcSIR), Anusandhan Bhawan, New Delhi, India
| | | | - Vaibhavi Dhuri
- Biochemical Sciences Division, CSIR-National Chemical Laboratory, Pune, 411008, India
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Brown R, Priest E, Naglik JR, Richardson JP. Fungal Toxins and Host Immune Responses. Front Microbiol 2021; 12:643639. [PMID: 33927703 PMCID: PMC8076518 DOI: 10.3389/fmicb.2021.643639] [Citation(s) in RCA: 31] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2020] [Accepted: 03/08/2021] [Indexed: 12/11/2022] Open
Abstract
Fungi are ubiquitous organisms that thrive in diverse natural environments including soils, plants, animals, and the human body. In response to warmth, humidity, and moisture, certain fungi which grow on crops and harvested foodstuffs can produce mycotoxins; secondary metabolites which when ingested have a deleterious impact on health. Ongoing research indicates that some mycotoxins and, more recently, peptide toxins are also produced during active fungal infection in humans and experimental models. A combination of innate and adaptive immune recognition allows the host to eliminate invading pathogens from the body. However, imbalances in immune homeostasis often facilitate microbial infection. Despite the wide-ranging effects of fungal toxins on health, our understanding of toxin-mediated modulation of immune responses is incomplete. This review will explore the current understanding of fungal toxins and how they contribute to the modulation of host immunity.
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Affiliation(s)
| | | | | | - Jonathan P. Richardson
- Centre for Host-Microbiome Interactions, Faculty of Dentistry, Oral & Craniofacial Sciences, King’s College London, London, United Kingdom
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Moore GG. Practical considerations will ensure the continued success of pre-harvest biocontrol using non-aflatoxigenic Aspergillus flavus strains. Crit Rev Food Sci Nutr 2021; 62:4208-4225. [PMID: 33506687 DOI: 10.1080/10408398.2021.1873731] [Citation(s) in RCA: 22] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
There is an important reason for the accelerated use of non-aflatoxigenic Aspergillus flavus to mitigate pre-harvest aflatoxin contamination… it effectively addresses the imperative need for safer food and feed. Now that we have decades of proof of the effectiveness of A. flavus as biocontrol, it is time to improve several aspects of this strategy. If we are to continue relying heavily on this form of aflatoxin mitigation, there are considerations we must acknowledge, and actions we must take, to ensure that we are best wielding this strategy to our advantage. These include its: (1) potential to produce other mycotoxins, (2) persistence in the field in light of several ecological factors, (3) its reproductive and genetic stability, (4) the mechanism(s) employed that allow it to elicit control over aflatoxigenic strains and species of agricultural importance and (5) supplemental alternatives that increase its effectiveness. There is a need to be consistent, practical and thoughtful when it comes to implementing this method of mycotoxin mitigation since these fungi are living organisms that have been adapting, evolving and surviving on this planet for tens-of-millions of years. This document will serve as a critical review of the literature regarding pre-harvest A. flavus biocontrol and will discuss opportunities for improvements.
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Affiliation(s)
- Geromy G Moore
- United States Department of Agriculture, Agricultural Research Service, New Orleans, USA
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10
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Wang L, He L, Zeng H, Fu W, Wang J, Tan Y, Zheng C, Qiu Z, Luo J, Lv C, Huang Y, Shu W. Low-dose microcystin-LR antagonizes aflatoxin B1 induced hepatocarcinogenesis through decreasing cytochrome P450 1A2 expression and aflatoxin B1-DNA adduct generation. CHEMOSPHERE 2020; 248:126036. [PMID: 32045972 DOI: 10.1016/j.chemosphere.2020.126036] [Citation(s) in RCA: 23] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/26/2019] [Revised: 01/24/2020] [Accepted: 01/24/2020] [Indexed: 06/10/2023]
Abstract
Aflatoxin B1 (AFB1) and microcystin-LR (MC-LR) co-existed in food and water, and were associated with hepatocellular carcinoma (HCC). AFB1 induced HCC by activating oxidative stress and generating AFB1-DNA adducts, while MC-LR could promote HCC progression. However, whether they have co-effects in HCC progression remains uncertain. In this study, we found the antagonistic effects of MC-LR on AFB1 induced HCC when they were exposed simultaneously. Compared with single exposure to AFB1, co-exposed to MC-LR significantly repressed the AFB1 induced malignant transformation of human hepatic cells and the glutathione S-transferase Pi positive foci formation in rat livers. MC-LR inhibited AFB1 induced upregulation of cytochrome P450 family 1 subfamily A member 2 (CYP1A2) and reduced the AFB1-DNA adducts generation in both human hepatic cells and rat livers. These results suggest that when co-exposure with AFB1, MC-LR might repress hepatocarcinogenicity of AFB1, which might be associated with its repression on AFB1 induced CYP1A2 upregulation and activation.
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Affiliation(s)
- Lingqiao Wang
- Department of Environmental Hygiene, College of Preventive Medicine, Army Medical University (Third Military Medical University), Chongqing, 400038, China
| | - Lixiong He
- The 8th Medical Center of Chinese PLA General Hospital, Beijing, 100094, China
| | - Hui Zeng
- Department of Environmental Hygiene, College of Preventive Medicine, Army Medical University (Third Military Medical University), Chongqing, 400038, China
| | - Wenjuan Fu
- Institute of Pathology and Southwest Cancer Center, Southwest Hospital, Army Medical University (Third Military Medical University), Chongqing, 400038, China
| | - Jia Wang
- Department of Environmental Hygiene, College of Preventive Medicine, Army Medical University (Third Military Medical University), Chongqing, 400038, China
| | - Yao Tan
- Department of Environmental Hygiene, College of Preventive Medicine, Army Medical University (Third Military Medical University), Chongqing, 400038, China
| | - Chuanfen Zheng
- Department of Health Education, College of Preventive Medicine, Army Medical University (Third Military Medical University), Chongqing, 400038, China
| | - Zhiqun Qiu
- Department of Environmental Hygiene, College of Preventive Medicine, Army Medical University (Third Military Medical University), Chongqing, 400038, China
| | - Jiaohua Luo
- Department of Environmental Hygiene, College of Preventive Medicine, Army Medical University (Third Military Medical University), Chongqing, 400038, China
| | - Chen Lv
- Department of Environmental Hygiene, College of Preventive Medicine, Army Medical University (Third Military Medical University), Chongqing, 400038, China
| | - Yujing Huang
- Department of Environmental Hygiene, College of Preventive Medicine, Army Medical University (Third Military Medical University), Chongqing, 400038, China.
| | - Weiqun Shu
- Department of Environmental Hygiene, College of Preventive Medicine, Army Medical University (Third Military Medical University), Chongqing, 400038, China.
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Norlia M, Jinap S, Nor-Khaizura MAR, Radu S, Chin CK, Samsudin NIP, Farawahida AH. Molecular Characterisation of Aflatoxigenic and Non-Aflatoxigenic Strains of Aspergillus Section Flavi Isolated from Imported Peanuts along the Supply Chain in Malaysia. Toxins (Basel) 2019; 11:E501. [PMID: 31470527 PMCID: PMC6784170 DOI: 10.3390/toxins11090501] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2019] [Revised: 06/25/2019] [Accepted: 07/10/2019] [Indexed: 11/16/2022] Open
Abstract
Peanuts are widely consumed in many local dishes in southeast Asian countries, especially in Malaysia which is one of the major peanut-importing countries in this region. Therefore, Aspergillus spp. and aflatoxin contamination in peanuts during storage are becoming major concerns due to the tropical weather in this region that favours the growth of aflatoxigenic fungi. The present study thus aimed to molecularly identify and characterise the Aspergillus section Flavi isolated from imported peanuts in Malaysia. The internal transcribed spacer (ITS) and β-tubulin sequences were used to confirm the species and determine the phylogenetic relationship among the isolates, while aflatoxin biosynthesis genes (aflR, aflP (omtA), aflD (nor-1), aflM (ver-1), and pksA) were targeted in a multiplex PCR to determine the toxigenic potential. A total of 76 and one isolates were confirmed as A. flavus and A. tamarii, respectively. The Maximum Likelihood (ML) phylogenetic tree resolved the species into two different clades in which all A. flavus (both aflatoxigenic and non-aflatoxigenic) were grouped in the same clade and A. tamarii was grouped in a different clade. The aflatoxin biosynthesis genes were detected in all aflatoxigenic A. flavus while the non-aflatoxigenic A. flavus failed to amplify at least one of the genes. The results indicated that both aflatoxigenic and non-aflatoxigenic A. flavus could survive in imported peanuts and, thus, appropriate storage conditions preferably with low temperature should be considered to avoid the re-emergence of aflatoxigenic A. flavus and the subsequent aflatoxin production in peanuts during storage.
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Affiliation(s)
- Mahror Norlia
- Department of Food Science and Technology, Faculty of Food Science and Technology, Universiti Putra Malaysia, UPM Serdang, Selangor 43400, Malaysia
- School of Industrial Technology, Universiti Sains Malaysia, Minden 11800, Pulau Pinang, Malaysia
| | - Selamat Jinap
- Department of Food Science and Technology, Faculty of Food Science and Technology, Universiti Putra Malaysia, UPM Serdang, Selangor 43400, Malaysia.
- Laboratory of Food Safety and Food Integrity, Institute of Tropical Agriculture and Food Security, Universiti Putra Malaysia, UPM Serdang, Selangor 43400, Malaysia.
| | - Mahmud Ab Rashid Nor-Khaizura
- Department of Food Science and Technology, Faculty of Food Science and Technology, Universiti Putra Malaysia, UPM Serdang, Selangor 43400, Malaysia
| | - Son Radu
- Department of Food Science and Technology, Faculty of Food Science and Technology, Universiti Putra Malaysia, UPM Serdang, Selangor 43400, Malaysia
- Laboratory of Food Safety and Food Integrity, Institute of Tropical Agriculture and Food Security, Universiti Putra Malaysia, UPM Serdang, Selangor 43400, Malaysia
| | - Cheow Keat Chin
- Food Safety and Quality Division, Ministry of Health Malaysia, Putrajaya 62675, Malaysia
| | - Nik Iskandar Putra Samsudin
- Department of Food Science and Technology, Faculty of Food Science and Technology, Universiti Putra Malaysia, UPM Serdang, Selangor 43400, Malaysia
- Laboratory of Food Safety and Food Integrity, Institute of Tropical Agriculture and Food Security, Universiti Putra Malaysia, UPM Serdang, Selangor 43400, Malaysia
| | - Abdul Halim Farawahida
- Department of Food Science and Technology, Faculty of Food Science and Technology, Universiti Putra Malaysia, UPM Serdang, Selangor 43400, Malaysia
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12
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Peterson SW, Ito Y, Horn BW, Goto T. Aspergillus bombycis, a new aflatoxigenic species and genetic variation in its sibling species,A. nomius. Mycologia 2019. [DOI: 10.1080/00275514.2001.12063200] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
Affiliation(s)
- Stephen W. Peterson
- Microbial Properties Research Unit, National Center for Agricultural Utilization Research, Agricultural Research Service, U.S. Department of Agriculture, 1815 N. University St., Peoria, Illinois 61604-3999 USA
| | - Yoko Ito
- National Research Institute for Vegetables, Ornamental Plants and Tea, Ministry of Agriculture Forestry and Fisheries, Ano, Mie, 514-2392 Japan
| | - Bruce W. Horn
- National Peanut Research Laboratory, Agricultural Research Service, U.S. Department of Agriculture, 1011 Forrester Dr. SE, Dawson, Georgia 31742 USA
| | - Tetsuhisa Goto
- National Food Research Institute, Ministry of Agriculture Forestry and Fisheries, Kannondai, Tsukuba, 305-8642 Japan
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13
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Pandey MK, Kumar R, Pandey AK, Soni P, Gangurde SS, Sudini HK, Fountain JC, Liao B, Desmae H, Okori P, Chen X, Jiang H, Mendu V, Falalou H, Njoroge S, Mwololo J, Guo B, Zhuang W, Wang X, Liang X, Varshney RK. Mitigating Aflatoxin Contamination in Groundnut through A Combination of Genetic Resistance and Post-Harvest Management Practices. Toxins (Basel) 2019; 11:E315. [PMID: 31163657 PMCID: PMC6628460 DOI: 10.3390/toxins11060315] [Citation(s) in RCA: 48] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2019] [Revised: 05/19/2019] [Accepted: 05/23/2019] [Indexed: 01/12/2023] Open
Abstract
Aflatoxin is considered a "hidden poison" due to its slow and adverse effect on various biological pathways in humans, particularly among children, in whom it leads to delayed development, stunted growth, liver damage, and liver cancer. Unfortunately, the unpredictable behavior of the fungus as well as climatic conditions pose serious challenges in precise phenotyping, genetic prediction and genetic improvement, leaving the complete onus of preventing aflatoxin contamination in crops on post-harvest management. Equipping popular crop varieties with genetic resistance to aflatoxin is key to effective lowering of infection in farmer's fields. A combination of genetic resistance for in vitro seed colonization (IVSC), pre-harvest aflatoxin contamination (PAC) and aflatoxin production together with pre- and post-harvest management may provide a sustainable solution to aflatoxin contamination. In this context, modern "omics" approaches, including next-generation genomics technologies, can provide improved and decisive information and genetic solutions. Preventing contamination will not only drastically boost the consumption and trade of the crops and products across nations/regions, but more importantly, stave off deleterious health problems among consumers across the globe.
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Affiliation(s)
- Manish K Pandey
- International Crops Research Institute for the Semi-Arid Tropics (ICRISAT), Hyderabad 502324, India.
| | - Rakesh Kumar
- International Crops Research Institute for the Semi-Arid Tropics (ICRISAT), Hyderabad 502324, India.
| | - Arun K Pandey
- International Crops Research Institute for the Semi-Arid Tropics (ICRISAT), Hyderabad 502324, India.
| | - Pooja Soni
- International Crops Research Institute for the Semi-Arid Tropics (ICRISAT), Hyderabad 502324, India.
| | - Sunil S Gangurde
- International Crops Research Institute for the Semi-Arid Tropics (ICRISAT), Hyderabad 502324, India.
| | - Hari K Sudini
- International Crops Research Institute for the Semi-Arid Tropics (ICRISAT), Hyderabad 502324, India.
| | - Jake C Fountain
- Crop Protection and Management Research Unit, United State Department of Agriculture-Agricultural Research Service (USDA-ARS), Tifton, GA 31793, USA.
- Department of Plant Pathology, University of Georgia, Tifton, GA 31793, USA.
| | - Boshou Liao
- Oil Crops Research Institute (OCRI) of Chinese Academy of Agricultural Sciences (CAAS), Wuhan 430062, China.
| | - Haile Desmae
- International Crops Research Institute for the Semi-Arid Tropics (ICRISAT), Bamako BP 320, Mali.
| | - Patrick Okori
- International Crops Research Institute for the Semi-Arid Tropics (ICRISAT), Lilongwe PB 1096, Malawi.
| | - Xiaoping Chen
- Crops Research Institute (CRI) of Guangdong Academy of Agricultural Sciences (GAAS), Guangzhou 510640, China.
| | - Huifang Jiang
- Oil Crops Research Institute (OCRI) of Chinese Academy of Agricultural Sciences (CAAS), Wuhan 430062, China.
| | - Venugopal Mendu
- Department of Plant and Soil Science, Texas Tech University, Lubbock, TX 79409, USA.
| | - Hamidou Falalou
- International Crops Research Institute for the Semi-Arid Tropics (ICRISAT), Niamey BP 12404, Niger.
| | - Samuel Njoroge
- International Crops Research Institute for the Semi-Arid Tropics (ICRISAT), Lilongwe PB 1096, Malawi.
| | - James Mwololo
- International Crops Research Institute for the Semi-Arid Tropics (ICRISAT), Lilongwe PB 1096, Malawi.
| | - Baozhu Guo
- Crop Protection and Management Research Unit, United State Department of Agriculture-Agricultural Research Service (USDA-ARS), Tifton, GA 31793, USA.
| | - Weijian Zhuang
- Institute of Oil Crops, Fujian Agriculture and Forestry University, Fuzhou 350002, China.
| | - Xingjun Wang
- Shandong Academy of Agricultural Sciences, Jinan 250108, China.
| | - Xuanqiang Liang
- Crops Research Institute (CRI) of Guangdong Academy of Agricultural Sciences (GAAS), Guangzhou 510640, China.
| | - Rajeev K Varshney
- International Crops Research Institute for the Semi-Arid Tropics (ICRISAT), Hyderabad 502324, India.
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14
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Chen Y, Kong Q, Liang Y. Three newly identified peptides from Bacillus megaterium strongly inhibit the growth and aflatoxin B1 production of Aspergillus flavus. Food Control 2019. [DOI: 10.1016/j.foodcont.2018.07.040] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
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15
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Feibelman TP, Cotty PJ, Doster MA, Michailides TJ. A morphologically distinct strain ofAspergillus nomius. Mycologia 2018. [DOI: 10.1080/00275514.1998.12026951] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
Affiliation(s)
- Toby P. Feibelman
- USDA, ARS, Southern Regional Research Center, New Orleans, Louisiana 70124
| | - Peter J. Cotty
- USDA, ARS, Southern Regional Research Center, New Orleans, Louisiana 70124
| | - M. A. Doster
- Univ. of California, Davis, Kearney Agricultural Center, Parlier, California 93648
| | - T. J. Michailides
- Univ. of California, Davis, Kearney Agricultural Center, Parlier, California 93648
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16
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Maragos CM. Complexation of the Mycotoxin Cyclopiazonic Acid with Lanthanides Yields Luminescent Products. Toxins (Basel) 2018; 10:E285. [PMID: 29996475 PMCID: PMC6071049 DOI: 10.3390/toxins10070285] [Citation(s) in RCA: 5] [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: 06/08/2018] [Revised: 06/29/2018] [Accepted: 07/02/2018] [Indexed: 11/29/2022] Open
Abstract
Cycopiazonic acid (CPA) is a neurotoxin that acts through inhibition of the sarco(endo)plasmic reticulum Ca2+-ATPase (SERCA). CPA blocks the calcium access channel of the enzyme. The inhibition may involve the binding of CPA with a divalent cation such as Mg2+. The potential for CPA to act as a chelator also has implications for methods to detect this toxin. Certain of the lanthanide metals undergo a dramatic increase in luminescence upon coordination with small molecules that can transfer excitation energy to the metal. This report is the first to describe the coordination of CPA with lanthanide metals, resulting in a substantial enhancement of their luminescence. The luminescence expressed was dependent upon the type of lanthanide, its concentration, and the environment (solvent, water content, pH). Based upon the phenomenon, a competitive assay was also developed wherein terbium (Tb3+) and a series of metal cations competed for binding with CPA. With increasing cation concentration, the luminescence of the CPA/Tb3+ complex was inhibited. The chlorides of ten metals were tested. Inhibition was best with Cu2+, followed by Co2+, Al3+, Fe3+, Mn2+, Au3+, Mg2+, and Ca2+. Two cations in oxidation state one (Na⁺, K⁺) did not inhibit the interaction significantly. The interaction of CPA with lanthanides provides a novel recognition assay for this toxin. It also provides a novel way to probe the binding of CPA to metals, giving insights into CPA’s mechanism of action.
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Affiliation(s)
- Chris M Maragos
- Mycotoxin Prevention and Applied Microbiology Research Unit, Agricultural Research Service, U.S. Department of Agriculture, Peoria, IL 61604, USA.
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17
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Wielgusz K, Irzykowska L. Occurrence of pathogenic and endophytic fungi and their influence on quality of medicinal plants applied in management of neurological diseases and mental disorders. HERBA POLONICA 2018. [DOI: 10.1515/hepo-2017-0025] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
Summary
Due to increasing demand of medicinal plants (MPs), quality and safety more attention to the plant health should be paid. Among herb pathogens, especially fungi cause serious diseases in these plants decreasing yield and quality of herbal raw material. Some species, i.e. Fusarium sp., Alternaria sp., Penicillium sp. are known as mycotoxin producers. Paradoxically, self-treatment with herbal raw material can expose the patient to mycotoxin activity. In tissues of some MPs species, asymptomatically endophytic fungi residue. It is known that they are able to influence a biosynthesis of secondary metabolites in their host plant or produce biologically active compounds. Until recently these microorganisms have been neglected as a component of MPs, the reason why there have unexplored bioactivity and biodiversity. The paper presents an overview of herbal plants that are used in the treatment of nervous system diseases. Pathogenic fungi that infect these plants are described. It focused mainly on species producing harmful mycotoxins. The publication presents a list of these mycotoxins and a brief description of their effects on human health. The second part of this article provides information on the occurrence of endophytic fungi in herbal plants and their effects on human health. Coexistence of fungi and medicinal plants is not fully understood but can be crucial to ensure health and safety of patients with neurological diseases and mental disorders.
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Affiliation(s)
- Katarzyna Wielgusz
- Institute of Natural Fibers and Medicinal Plants Department of Breeding and Agriculture of Fibrous and Energetic Plants Wojska Polskiego 71b 60-630 Poznań , Poland
| | - Lidia Irzykowska
- Poznan University of Life Sciences Department of Phytopathology, Seed Science and Technology Dąbrowskiego 159 60-594 Poznań , Poland
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18
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Ostry V, Toman J, Grosse Y, Malir F. Cyclopiazonic acid: 50th anniversary of its discovery. WORLD MYCOTOXIN J 2018. [DOI: 10.3920/wmj2017.2243] [Citation(s) in RCA: 35] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
In 1968, the mycotoxin cyclopiazonic acid (CPA) was first discovered and characterised as a chemical substance. Within the following five decades, much has been learned from the results of CPA research. CPA is produced by several Penicillium species (P. griseofulvum, P. camemberti, P. commune, P. dipodomyicola) and Aspergillus species (A. flavus, A. oryzae and A. tamarii). It is widespread on naturally contaminated agricultural raw materials. CPA has been reported to occur in food commodities (e.g. oilseeds, nuts, cereals, dried figs, milk, cheese and meat products) and to possess toxicological significance. CPA is also frequently detected in peanuts and maize; the presence of CPA and aflatoxins in maize and peanuts contaminated with A. flavus suggests that synergism may occur. CPA is toxic to several animal species, such as rats, pigs, guinea pigs, poultry and dogs. After ingesting CPA-contaminated feeds, test animals display severe gastrointestinal upsets and neurological disorders. Organs affected include the liver, kidney, heart, and digestive tract, which show degenerative changes and necrosis. Biologically, CPA is a specific inhibitor of sarco(endo)plasmic reticulum Ca2+-ATPase. Data from toxicological evaluation of aflatoxins and CPA in broiler chickens demonstrate that both aflatoxins and CPA alone and the aflatoxin-CPA combination can adversely affect broiler health. The effects of aflatoxins and CPA combination were additive in most cases.
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Affiliation(s)
- V. Ostry
- National Institute of Public Health, Centre for Health, Nutrition and Food, National Reference Centre for Microfungi and Mycotoxins in Food Chains, Palackeho 3a, 61242 Brno, Czech Republic
| | - J. Toman
- University of Hradec Kralove, Department of Biology, Faculty of Science, Rokitanskeho 62, 50003 Hradec Kralove, Czech Republic
| | - Y. Grosse
- International Agency for Research on Cancer, 150 Cours Albert Thomas, 69372 Lyon Cedex 08, France
| | - F. Malir
- University of Hradec Kralove, Department of Biology, Faculty of Science, Rokitanskeho 62, 50003 Hradec Kralove, Czech Republic
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19
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Liu W, Wang L, Zheng C, Liu L, Wang J, Li D, Tan Y, Zhao X, He L, Shu W. Microcystin-LR increases genotoxicity induced by aflatoxin B1 through oxidative stress and DNA base excision repair genes in human hepatic cell lines. ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2018; 233:455-463. [PMID: 29100183 DOI: 10.1016/j.envpol.2017.10.067] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/08/2016] [Revised: 10/12/2017] [Accepted: 10/16/2017] [Indexed: 06/07/2023]
Abstract
Aflatoxin B1 (AFB1) and microcystin-LR (MC-LR) simultaneously exist in polluted food and water in humid and warm areas, and each has been reported to be genotoxic to liver and associated with hepatocellular carcinoma (HCC). However, the genotoxic effects of the two biotoxins in combination and potential mechanism remain unknown. We treated the human hepatic cell line HL7702 with AFB1 and MC-LR together at different ratios, examined their genotoxic effects using micronuclei and comet assays, and evaluated the possible mechanism by measuring oxidative stress markers and DNA base excision repair (BER) genes. Our data show that co-exposure to AFB1 and MC-LR significantly increased DNA damage compared with AFB1 or MC-LR alone as measured by the levels of both micronuclei and tail DNA. Meanwhile, AFB1 and MC-LR co-exposure showed biphasic effects on ROS production, and a gradual trend towards increased Glutathione (GSH) levels and activity of Catalase (CAT) and Superoxide Dismutase (SOD). Furthermore, MC-LR, with or without AFB1, significantly down-regulated the expression of the base excision repair (BER) genes 8-oxoguanine glycosylase-1 (OGG1) and X-ray repair cross complementing group 1 (XRCC1). AFB1 and MC-LR in combination upregulated the expression of the BER gene apurinic/apyrimidinic endonuclease 1 (APE1), whereas either agent alone had no effect. In conclusion, our studies show that MC-LR exacerbates AFB1-induced genotoxicity and we report for the first time that this occurs through effects on oxidative stress and the deregulation of DNA base excision repair genes.
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Affiliation(s)
- Wenyi Liu
- Department of Environmental Hygiene, College of Preventive Medicine, Third Military Medical University, Chongqing 400038, China; Center for Disease Control and Prevention of Guangzhou Military Command, Dongguanzhuang Road NO.91, Tianhe District, Guangzhou 510507, China
| | - Lingqiao Wang
- Department of Environmental Hygiene, College of Preventive Medicine, Third Military Medical University, Chongqing 400038, China
| | - Chuanfen Zheng
- Department of Environmental Hygiene, College of Preventive Medicine, Third Military Medical University, Chongqing 400038, China
| | - Lebin Liu
- Center for Disease Control and Prevention of Guangzhou Military Command, Dongguanzhuang Road NO.91, Tianhe District, Guangzhou 510507, China
| | - Jia Wang
- Department of Environmental Hygiene, College of Preventive Medicine, Third Military Medical University, Chongqing 400038, China
| | - Daibo Li
- Center for Disease Control and Prevention of Guangzhou Military Command, Dongguanzhuang Road NO.91, Tianhe District, Guangzhou 510507, China
| | - Yao Tan
- Department of Environmental Hygiene, College of Preventive Medicine, Third Military Medical University, Chongqing 400038, China
| | - Xilong Zhao
- Kunming General Hospital of Chengdu Military Command, Kunming 650032, China
| | - Lixiong He
- Department of Environmental Hygiene, College of Preventive Medicine, Third Military Medical University, Chongqing 400038, China
| | - Weiqun Shu
- Department of Environmental Hygiene, College of Preventive Medicine, Third Military Medical University, Chongqing 400038, China.
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20
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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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21
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Lee H, Nguyen-Viet H, Lindahl J, Thanh H, Khanh T, Hien L, Grace D. A survey of aflatoxin B1 in maize and awareness of aflatoxins in Vietnam. WORLD MYCOTOXIN J 2017. [DOI: 10.3920/wmj2016.2144] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Vietnam is a tropical country with high temperature and precipitation, which may provide good conditions for fungal growth. A few limited studies have been conducted to evaluate the level of aflatoxin B1 in maize in Vietnam. In addition, no studies have been conducted to evaluate the perception and knowledge of aflatoxins in Vietnam. Therefore, the main objective of this study was to determine the levels of aflatoxin B1 for human and animal consumption in maize and evaluate perceptions and knowledge of aflatoxins among people across the country. A total of 2,370 samples were collected from six provinces and analysed using ELISA. Among collected samples, 799 samples (33.71%, 95% confidence interval (CI): 31.81-35.66%) and 687 samples (28.98%, 95%CI: 27.17-30.86%) had levels above 2 µg/kg and 5 µg/kg, respectively [range from below limit of detection (LOD) to 34.8 µg/kg; of the samples above LOD, the mean was 13.1 µg/kg and median was 11.2 µg/kg]. A total of 551 people were interviewed from 6 provinces. The survey showed that awareness of aflatoxins (question: Have you heard about aflatoxins?) in southern Vietnam [An Giang (25%), Dak Lak (23.23%) and Dong Nai (6%)] was relatively higher than in provinces in northern Vietnam. We believe that this analysed information can be useful to better understand the epidemiology of aflatoxins in different provinces. This study also produces evidence on potential risk to humans and animals in Vietnam as well as demographic factors (such as gender and level of education) significantly influencing knowledge of aflatoxins. In conclusion, this paper points to the importance of raising the awareness of the risks with aflatoxins, bearing in mind the gender aspect during capacity development.
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Affiliation(s)
- H.S. Lee
- International Livestock Research Institute (ILRI), Dept. of Food Safety and Zoonoses, Room 301-302, B1 Building, Van Phuc Diplomatic Compound, 298 Kim Ma Street, Ba Dinh District, Hanoi 00100, Vietnam
| | - H. Nguyen-Viet
- International Livestock Research Institute (ILRI), Dept. of Food Safety and Zoonoses, Room 301-302, B1 Building, Van Phuc Diplomatic Compound, 298 Kim Ma Street, Ba Dinh District, Hanoi 00100, Vietnam
| | - J. Lindahl
- International Livestock Research Institute (ILRI), Dept. of Food Safety and Zoonoses, 30709 Naivasha Rd, Nairobi, Kenya
- Swedish University of Agricultural Sciences, Institutionen för kliniska vetenskaper, P.O. Box 7054, 750 07 Uppsala, Sweden
| | - H.M. Thanh
- Plant Protection Research Institute (PPRI), Duc thang commune, Dong Ngac, Tu Liem District, Hanoi 084, Vietnam
| | - T.N. Khanh
- Plant Protection Research Institute (PPRI), Duc thang commune, Dong Ngac, Tu Liem District, Hanoi 084, Vietnam
| | - L.T.T. Hien
- Plant Protection Research Institute (PPRI), Duc thang commune, Dong Ngac, Tu Liem District, Hanoi 084, Vietnam
| | - D. Grace
- International Livestock Research Institute (ILRI), Dept. of Food Safety and Zoonoses, 30709 Naivasha Rd, Nairobi, Kenya
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22
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Detection of cyclopiazonic acid (CPA) in maize by immunoassay. Mycotoxin Res 2017; 33:157-165. [DOI: 10.1007/s12550-017-0275-0] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2017] [Revised: 03/23/2017] [Accepted: 03/27/2017] [Indexed: 11/26/2022]
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23
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Ahmed Adam MA, Tabana YM, Musa KB, Sandai DA. Effects of different mycotoxins on humans, cell genome and their involvement in cancer (Review). Oncol Rep 2017; 37:1321-1336. [PMID: 28184933 DOI: 10.3892/or.2017.5424] [Citation(s) in RCA: 57] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2016] [Accepted: 01/16/2017] [Indexed: 11/06/2022] Open
Abstract
The chemical nature of most of the mycotoxins makes them highly liposoluble compounds that can be absorbed from the site of exposure such as from the gastrointestinal and respiratory tract to the blood stream where it can be dissimilated throughout the body and reach different organs such as the liver and kidneys. Mycotoxins have a strong tendency and ability to penetrate the human and animal cells and reach the cellular genome where it causes a major mutagenic change in the nucleotide sequence which leads to strong and permanent defects in the genome. This defect will eventually be transcribed, translated and lead to the development of cancer. In this review, the chemical and physical nature of mycotoxins, the action of mycotoxins on the cellular genome and its effect on humans, mycotoxins and their carcinogenicity and mycotoxins research gaps are discussed, and new research areas are suggested. The research review posed various questions. What are the different mycotoxins that can cause cancer, what is the role of mycotoxins in causing cancer and what types of cancers can be caused by mycotoxins? These questions have been selected due to the significant increase in the mycotoxin contamination and the cancer incidence rate in the contemporary world. By revealing and understanding the role of mycotoxins in developing cancer, measures to reduce the risks and incidents of cancer could be taken.
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Affiliation(s)
- Mowaffaq Adam Ahmed Adam
- Infectomics Cluster, Advanced Medical and Dental Institute, Universiti Sains Malaysia, Penang, Malaysia
| | - Yasser M Tabana
- Infectomics Cluster, Advanced Medical and Dental Institute, Universiti Sains Malaysia, Penang, Malaysia
| | - Khirun Binti Musa
- Infectomics Cluster, Advanced Medical and Dental Institute, Universiti Sains Malaysia, Penang, Malaysia
| | - Doblin Anak Sandai
- Infectomics Cluster, Advanced Medical and Dental Institute, Universiti Sains Malaysia, Penang, Malaysia
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Wang Y, Zhao C, Zhang D, Zhao M, Zheng D, Lyu Y, Cheng W, Guo P, Cui Z. Effective degradation of aflatoxin B 1 using a novel thermophilic microbial consortium TADC7. BIORESOURCE TECHNOLOGY 2017; 224:166-173. [PMID: 27866802 DOI: 10.1016/j.biortech.2016.11.033] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/15/2016] [Revised: 11/06/2016] [Accepted: 11/07/2016] [Indexed: 06/06/2023]
Abstract
We constructed a novel thermophilic microbial consortium, TADC7, with stable and efficient aflatoxin B1 (AFB1) degradation activity. The microbial consortium degraded more than 95% of the toxin within 72h when cultured with AFB1, and the optimum temperature was 55-60°C. TADC7 tolerated high doses of AFB1, with no inhibitory effects up to 5000μgL-1 AFB1; moreover, the degradation kinetics fit well with the Monod model. The proteins or enzymes in the TADC7 cell-free supernatant played a major role in AFB1 degradation. AFB1 degradation by the cell-free supernatant was stable up to 90°C, with an optimal pH of 8-10. We performed 16S rRNA sequencing to determine TADC7 community structure dynamics; the results indicated that Geobacillus and Tepidimicrobium played major roles in AFB1 degradation.
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Affiliation(s)
- Yi Wang
- Institute of Agricultural Products Processing and Nuclear Agriculture Technology Research, Hubei Academy of Agricultural Sciences, Wuhan 430064, China; College of Biology and Pharmacy, Three Gorges University, Yichang 443002, China
| | - Chunxia Zhao
- Institute of Agricultural Products Processing and Nuclear Agriculture Technology Research, Hubei Academy of Agricultural Sciences, Wuhan 430064, China; College of Biology and Pharmacy, Three Gorges University, Yichang 443002, China
| | - Dongdong Zhang
- Institute of Marine Biology, Ocean College, Zhejiang University, Zhoushan 316021, Zhejiang, China
| | - Mingming Zhao
- Institute of Agricultural Products Processing and Nuclear Agriculture Technology Research, Hubei Academy of Agricultural Sciences, Wuhan 430064, China
| | - Dan Zheng
- Institute of Agricultural Products Processing and Nuclear Agriculture Technology Research, Hubei Academy of Agricultural Sciences, Wuhan 430064, China
| | - Yucai Lyu
- College of Biology and Pharmacy, Three Gorges University, Yichang 443002, China
| | - Wei Cheng
- Institute of Agricultural Products Processing and Nuclear Agriculture Technology Research, Hubei Academy of Agricultural Sciences, Wuhan 430064, China
| | - Peng Guo
- Institute of Agricultural Products Processing and Nuclear Agriculture Technology Research, Hubei Academy of Agricultural Sciences, Wuhan 430064, China.
| | - Zongjun Cui
- College of Agronomy and Biotechnology, China Agricultural University, Beijing 100193, China
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Abstract
Cyclopiazonic acid (CPA) is an indol-tetramic acid mycotoxin and is produced by the nearly ubiquitous molds, Aspergillus and Penicillium. CPA produced by these molds has been identified in a number of food sources (including, but not limited to, grain, legumes, meat, milk, and cheese) and from parasitic infections of man and other animals. Few incidents of CPA mycotoxicoses have been reported because of the benign nature of the intoxication, the small amounts present, and its effects may be disguised with concurrent aflatoxicosis (some toxicity data may have been generated using aflatoxin-contaminated CPA). CPA is absorbed in the gastrointestinal tract and following oral administration; it has a half-life of approximately 30 hours and is excreted largely unchanged in the urine and feces. Cyclopiazonic acid is not considered to be a potent acute toxin as its oral LD50 in rodents is in the range of 30 to 70 mg/kg. Multiple dose studies also show a range of effects in several species and among mammalian models, the pig appears to be the most sensitive with a no-observable-effect level (NOEL) in the range of 1.0 mg/kg/day. The preponderance of evidence from the rat and other test animals supports this dose as a defensible estimate of a no effect level. The target organs of CPA toxicity appear to be muscle, hepatic tissue, and spleen, with a localization in the former, although a more apparent toxic change in the latter two. The toxicity and symptoms of CPA poisoning can be attributed to its ability to alter normal intracellular calcium flux through its inhibition of the reticular form of the Ca2+-ATPase pump. CPA was not teratogenic in mice. CPA is not considered a carcinogen and the weight of evidence militates against its characterization as a mutagen. Despite CPA-induced pathological changes ascribed to the spleen or bursa of Fabricius, there does not appear to be an effect on the immune system. In vitro studies imply a potential immunomodulatory effect of CPA, but in all of those reports very high concentrations of CPA were required and none of these findings have been supported with in vivo studies. Therefore, based on a NOEL of 1 mg/kg/day and accounting for species variation, an appropriate acceptable daily intake (ADI) would be approximately 10 μg/kg/day or 700 μg/day. In the context of human exposure, if the uppermost limit of CPA found in cheese is 4 μg/g and the average individual consumes 50 g of cheese daily, this allows an intake of 200 μg, less than one third of a traditionally established ADI.
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Affiliation(s)
- G. A. Burdock
- Burdock and Associates, Inc., Vero Beach, Florida, USA
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Pandey AK, Sonker N, Singh P. Efficacy of Some Essential Oils AgainstAspergillus flavuswith Special Reference toLippia albaOil an Inhibitor of Fungal Proliferation and Aflatoxin B1Production in Green Gram Seeds during Storage. J Food Sci 2016; 81:M928-34. [DOI: 10.1111/1750-3841.13254] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2015] [Accepted: 01/26/2016] [Indexed: 11/30/2022]
Affiliation(s)
- Abhay K. Pandey
- Bacteriology and Natural Pesticide Laboratory, Dept. of Botany; DDU Gorakhpur Univ; Gorakhpur -273009 U.P India
- Plant Health Management Div; Natl. Inst. of Plant Health Management; Rajendra Nagar Hyderabad -500030 India
| | - Nivedita Sonker
- Bacteriology and Natural Pesticide Laboratory, Dept. of Botany; DDU Gorakhpur Univ; Gorakhpur -273009 U.P India
| | - Pooja Singh
- Bacteriology and Natural Pesticide Laboratory, Dept. of Botany; DDU Gorakhpur Univ; Gorakhpur -273009 U.P India
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Aflatoxigenic Fungi in Food Grains: Detection, Its Impact on Handlers and Management Strategies. Fungal Biol 2016. [DOI: 10.1007/978-3-319-27312-9_20] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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Raiola A, Tenore GC, Manyes L, Meca G, Ritieni A. Risk analysis of main mycotoxins occurring in food for children: An overview. Food Chem Toxicol 2015; 84:169-80. [PMID: 26327433 DOI: 10.1016/j.fct.2015.08.023] [Citation(s) in RCA: 91] [Impact Index Per Article: 10.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2015] [Revised: 08/22/2015] [Accepted: 08/24/2015] [Indexed: 01/11/2023]
Abstract
Mycotoxins are secondary metabolites produced by fungi contaminating the food chain that are toxic to animals and humans. Children up to 12 years old are recognized as a potentially vulnerable subgroup with respect to consumption of these contaminants. Apart from having a higher exposure per kg body weight, they have a different physiology from that of adults. Therefore they may be more sensitive to neurotoxic, endocrine and immunological effects. For these reasons, a specific and up-to-date risk analysis for this category is of great interest. In this review, an accurate analysis of the main mycotoxins occurring in food intended for children (deoxynivalenol, aflatoxins, ochratoxins, patulin and fumonisins) is presented. In particular, known mechanisms of toxicity and levels of exposure and bioaccessibility in children are shown. In addition, recent discoveries about the strategies of mycotoxins managing are discussed.
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Affiliation(s)
- Assunta Raiola
- Department of Agriculture, Faculty of Agriculture, University of Naples "Federico II", Via Universitá 100, 80055, Portici, Napoli, Italy.
| | - Gian Carlo Tenore
- Department of Pharmacy, Faculty of Pharmacy, University of Naples "Federico II", Via Domenico Montesano 49, 80131, Napoli, Italy
| | - Lara Manyes
- Laboratory of Food Chemistry and Toxicology, Faculty of Pharmacy, University of Valencia, Avenue Vicent Andrés Estellés s/n, 46100 Burjassot, Spain
| | - Giuseppe Meca
- Laboratory of Food Chemistry and Toxicology, Faculty of Pharmacy, University of Valencia, Avenue Vicent Andrés Estellés s/n, 46100 Burjassot, Spain
| | - Alberto Ritieni
- Department of Pharmacy, Faculty of Pharmacy, University of Naples "Federico II", Via Domenico Montesano 49, 80131, Napoli, Italy
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30
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Mohammadi Kouchesfahani M, Alimohammadi M, Jahed Khaniki G, Nabizadeh Nodehi R, Aghamohseni Z, Moazeni M, Rezaie S. Antifungal Effects of Ozonated Water on A
spergillus parasiticus
: A New Approach to Prevent Wheat Contamination. J Food Saf 2015. [DOI: 10.1111/jfs.12159] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- M. Mohammadi Kouchesfahani
- Department of Environmental Health Engineering; School of Public Health; Tehran University of Medical Sciences; Sari Iran
| | - M. Alimohammadi
- Department of Environmental Health Engineering; School of Public Health; Tehran University of Medical Sciences; Sari Iran
| | - G. Jahed Khaniki
- Department of Environmental Health Engineering; School of Public Health; Tehran University of Medical Sciences; Sari Iran
| | - R. Nabizadeh Nodehi
- Department of Environmental Health Engineering; School of Public Health; Tehran University of Medical Sciences; Sari Iran
| | - Z. Aghamohseni
- Department of Environmental Health Engineering; School of Public Health; Tehran University of Medical Sciences; Sari Iran
| | - M. Moazeni
- Invasive Fungi Research Centre; Department of Medical Mycology and Parasitology; School of Medicine; Mazandaran University of Medical Sciences; Sari Iran
| | - S. Rezaie
- Department of Medical Biotechnology; School of Advanced Technologies in Medicine; Tehran University of Medical Sciences; Sari Iran
- Department of Medical Parasitology and Mycology; School of Public Health; Tehran University of Medical Sciences; Sari Iran
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31
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da Silva FC, Chalfoun SM, Batista LR, Santos C, Lima N. Use of a polyphasic approach including MALDI-TOF MS for identification of Aspergillus section Flavi strains isolated from food commodities in Brazil. ANN MICROBIOL 2015. [DOI: 10.1007/s13213-015-1050-0] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023] Open
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32
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El-Bahr SM. Effect of curcumin on hepatic antioxidant enzymes activities and gene expressions in rats intoxicated with aflatoxin B1. Phytother Res 2014; 29:134-40. [PMID: 25639897 DOI: 10.1002/ptr.5239] [Citation(s) in RCA: 87] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2014] [Revised: 09/04/2014] [Accepted: 09/10/2014] [Indexed: 01/09/2023]
Abstract
Twenty-eight rats were examined in a 5-week experiment to investigate the effect of curcumin on gene expression and activities of hepatic antioxidant enzymes in rats intoxicated with aflatoxin B1 (AFB1 ). The rats were divided into four groups. Rats in 1-4 groups served as control, oral curcumin treated (15 mg/kg body weight), single i.p. dose of AFB1 (3 mg/kg body weight) and combination of single i.p. dose of AFB1 with oral curcumin treated, respectively. AFB1 Liver damage and oxidative stress were evident in untreated AFB1 -intoxicated rats as indicated by a significant elevation in hepatic transaminases, elevation in lipid peroxide biomarkers (thiobarbituric acid reactive substances; TBARS), reduction of reduced glutathione (GSH) concentration, reduction in the activities of antioxidant enzymes namely catalase (CAT), total superoxide dismutase (SOD), glutathione peroxidase (GPX) and glutathione-S-transferase (GST) and down-regulation of gene expression of these antioxidant enzymes compared to control. Liver sections of rats intoxicated with AFB1 showed a disrupted lobular architecture, scattered necrotic cells and biliary proliferation. Administration of curcumin with AFB1 resulted in amelioration of AFB1 -induced effects compared to untreated AFB1 -intoxicated rats via an up-regulation of antioxidant enzyme gene expression, activation of the expressed genes and increase in the availability of GSH.
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Affiliation(s)
- S M El-Bahr
- Department of Physiology, Biochemistry and Pharmacology (Biochemistry), College of Veterinary Medicine and Animal Resources, King Faisal University, P.O. Box 400, Al-Hufof, 31982, Saudi Arabia; Department of Biochemistry, Faculty of Veterinary Medicine, Alexandria University, Egypt
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Upadhyay A, Upadhyaya I, Kollanoor-Johny A, Venkitanarayanan K. Combating pathogenic microorganisms using plant-derived antimicrobials: a minireview of the mechanistic basis. BIOMED RESEARCH INTERNATIONAL 2014; 2014:761741. [PMID: 25298964 PMCID: PMC4178913 DOI: 10.1155/2014/761741] [Citation(s) in RCA: 92] [Impact Index Per Article: 9.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/25/2014] [Revised: 08/05/2014] [Accepted: 08/08/2014] [Indexed: 12/19/2022]
Abstract
The emergence of antibiotic resistance in pathogenic bacteria has led to renewed interest in exploring the potential of plant-derived antimicrobials (PDAs) as an alternative therapeutic strategy to combat microbial infections. Historically, plant extracts have been used as a safe, effective, and natural remedy for ailments and diseases in traditional medicine. Extensive research in the last two decades has identified a plethora of PDAs with a wide spectrum of activity against a variety of fungal and bacterial pathogens causing infections in humans and animals. Active components of many plant extracts have been characterized and are commercially available; however, research delineating the mechanistic basis of their antimicrobial action is scanty. This review highlights the potential of various plant-derived compounds to control pathogenic bacteria, especially the diverse effects exerted by plant compounds on various virulence factors that are critical for pathogenicity inside the host. In addition, the potential effect of PDAs on gut microbiota is discussed.
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Affiliation(s)
- Abhinav Upadhyay
- Department of Animal Science, University of Connecticut, 3636 Horsebarn Hill Road Extension, Unit 4040, Storrs, CT 06269, USA
| | - Indu Upadhyaya
- Department of Animal Science, University of Connecticut, 3636 Horsebarn Hill Road Extension, Unit 4040, Storrs, CT 06269, USA
| | - Anup Kollanoor-Johny
- Department of Animal Science, University of Connecticut, 3636 Horsebarn Hill Road Extension, Unit 4040, Storrs, CT 06269, USA
| | - Kumar Venkitanarayanan
- Department of Animal Science, University of Connecticut, 3636 Horsebarn Hill Road Extension, Unit 4040, Storrs, CT 06269, USA
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Doi K, Uetsuka K. Mechanisms of Mycotoxin-induced Dermal Toxicity and Tumorigenesis Through Oxidative Stress-related Pathways. J Toxicol Pathol 2014; 27:1-10. [PMID: 24791061 PMCID: PMC4000067 DOI: 10.1293/tox.2013-0062] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2013] [Accepted: 11/24/2013] [Indexed: 12/17/2022] Open
Abstract
Among the many mycotoxins, T-2 toxin, citrinin (CTN), patulin (PAT), aflatoxin B1 (AFB1) and ochratoxin A (OTA) are known to have the potential to induce dermal toxicity and/or tumorigenesis in rodent models. T-2 toxin, CTN, PAT and OTA induce apoptosis in mouse or rat skin. PAT, AFB1 and OTA have tumor initiating properties, and OTA is also a tumor promoter in mouse skin. This paper reviews the molecular mechanisms of dermal toxicity and tumorigenesis induced in rodent models by these mycotoxins especially from the viewpoint of oxidative stress-mediated pathways.
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Affiliation(s)
- Kunio Doi
- Bozo Research Center Inc., 8 Ohkubo, Tsukuba, Ibaraki 300-2611, Japan ; Graduate School of Agricultural and Life Sciences, The University of Tokyo, 1-1-1 Yayoi, Bunkyo, Tokyo 113-8657, Japan
| | - Koji Uetsuka
- Animal Health Laboratory, College of Agriculture, Ibaraki University, 3-21-1, Ami-machi, Inashiki-gun, Ibaraki 300-0393, Japan
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35
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Afsah-Hejri L, Jinap S, Hajeb P, Radu S, Shakibazadeh S. A Review on Mycotoxins in Food and Feed: Malaysia Case Study. Compr Rev Food Sci Food Saf 2013; 12:629-651. [DOI: 10.1111/1541-4337.12029] [Citation(s) in RCA: 112] [Impact Index Per Article: 10.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2013] [Accepted: 06/17/2013] [Indexed: 01/15/2023]
Affiliation(s)
- L. Afsah-Hejri
- Food Safety Research Centre (FOSREC); Faculty of Food Science and Technology, Univ. Putra Malaysia; 43400 UPM; Serdang; Selangor; Malaysia
| | - S. Jinap
- Food Safety Research Centre (FOSREC); Faculty of Food Science and Technology, Univ. Putra Malaysia; 43400 UPM; Serdang; Selangor; Malaysia
| | - P. Hajeb
- Food Safety Research Centre (FOSREC); Faculty of Food Science and Technology, Univ. Putra Malaysia; 43400 UPM; Serdang; Selangor; Malaysia
| | - S. Radu
- Food Safety Research Centre (FOSREC); Faculty of Food Science and Technology, Univ. Putra Malaysia; 43400 UPM; Serdang; Selangor; Malaysia
| | - Sh. Shakibazadeh
- Dept. of Aquaculture, Faculty of Agriculture; Univ. Putra Malaysia; 43400, UPM Serdang; Selangor; Malaysia
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36
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Silambarasan S, Abraham J. Mycoremediation of endosulfan and its metabolites in aqueous medium and soil by Botryosphaeria laricina JAS6 and Aspergillus tamarii JAS9. PLoS One 2013; 8:e77170. [PMID: 24130848 PMCID: PMC3795002 DOI: 10.1371/journal.pone.0077170] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2013] [Accepted: 08/30/2013] [Indexed: 11/26/2022] Open
Abstract
Microbial degradation offers an efficient and ecofriendly approach to remove toxicants from the contaminated environments. Botryosphaeria laricina JAS6 and Aspergillus tamarii JAS9 were capable of degrading endosulfan and their metabolites which were isolated through enrichment technique. Both the strains were able to withstand an exposure of 1300 mg/L and showed luxuriant growth at 1000 mg/L of endosulfan. The change in pH in the culture broth was from 6.8 to 3.4 and 3.8 during growth kinetic studies of JAS6 and JAS9 strains, respectively upon biological degradation of endosulfan. The degradation of endosulfan by JAS6 and JAS9 strains were examined by HPLC. The biodegradation rate constant (k) and the initial concentration were reduced by 50% (DT50) which was determined by first and pseudo first order kinetic models. In the present investigation it has been revealed that Botryosphaeria laricina JAS6 and Aspergillus tamarii JAS9 possessing endosulfan degrading capability are being reported for the first time. These findings confirm the degradation of endosulfan by JAS6 and JAS9 strains which were accompanied by significant reduction in the toxicity and could be used as remedial measure in contaminated environments.
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Affiliation(s)
- Sivagnanam Silambarasan
- Microbial Biotechnology Laboratory, School of Biosciences and Technology, VIT University, Vellore, Tamil Nadu, India
| | - Jayanthi Abraham
- Microbial Biotechnology Laboratory, School of Biosciences and Technology, VIT University, Vellore, Tamil Nadu, India
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37
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Effects of sodium selenite on the decreased percentage of T cell subsets, contents of serum IL-2 and IFN-γ induced by aflatoxin B1 in broilers. Res Vet Sci 2013; 95:143-5. [DOI: 10.1016/j.rvsc.2013.02.019] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2012] [Revised: 02/20/2013] [Accepted: 02/27/2013] [Indexed: 11/21/2022]
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38
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Keratitis caused by Aspergillus pseudotamarii. Med Mycol Case Rep 2013; 2:91-4. [PMID: 24432226 DOI: 10.1016/j.mmcr.2013.04.002] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2013] [Revised: 04/05/2013] [Accepted: 04/05/2013] [Indexed: 11/22/2022] Open
Abstract
A male patient presented with complaints of redness, pain and defective vision in the left eye. The infiltrate healed completely after two weeks of topical natamycin administration. A polyphasic approach was used to identify the isolate as Aspergillus pseudotamarii, which produced aflatoxins in inducing medium.
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40
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Gifford DR, Schoustra SE. Modelling colony population growth in the filamentous fungus Aspergillus nidulans. J Theor Biol 2012; 320:124-30. [PMID: 23246716 DOI: 10.1016/j.jtbi.2012.12.003] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2012] [Revised: 09/28/2012] [Accepted: 12/05/2012] [Indexed: 12/25/2022]
Abstract
Filamentous fungi are ubiquitous in nature and have high societal significance, being both major (food-borne) pathogens and important industrial organisms in the production of antibiotics and enzymes. In addition, fungi are important model organisms for fundamental research, such as studies in genetics and evolutionary biology. However, mechanistic models for population growth that would help understand fungal biology and fundamental processes are almost entirely missing. Here we present such a mechanistic model for the species Aspergillus nidulans as an exemplar of models for other filamentous fungi. The model is based on physiological parameters that influence colony growth, namely mycelial growth rate and sporulation rate, to predict the number of individual nuclei present in a colony through time. Using population size data for colonies of differing ages, we find that our mechanistic model accurately predicts the number of nuclei for two growth environments, and show that fungal population size is most dependent on changes in mycelial growth rate.
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41
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Endophytic fungus Aspergillus tamarii from Ficus carica L., a new source of indolyl diketopiperazines. BIOCHEM SYST ECOL 2012. [DOI: 10.1016/j.bse.2012.07.020] [Citation(s) in RCA: 16] [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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42
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Ahmad M, Ahmad MM, Hamid R, Abdin MZ, Javed S. Use of response surface methodology to study the effect of media composition on aflatoxin production by Aspergillus flavus. Mycotoxin Res 2012; 29:39-45. [DOI: 10.1007/s12550-012-0151-x] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2012] [Revised: 10/15/2012] [Accepted: 10/17/2012] [Indexed: 11/24/2022]
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43
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Yu J. Current understanding on aflatoxin biosynthesis and future perspective in reducing aflatoxin contamination. Toxins (Basel) 2012; 4:1024-57. [PMID: 23202305 PMCID: PMC3509697 DOI: 10.3390/toxins4111024] [Citation(s) in RCA: 197] [Impact Index Per Article: 16.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2012] [Revised: 10/08/2012] [Accepted: 10/09/2012] [Indexed: 01/20/2023] Open
Abstract
Traditional molecular techniques have been used in research in discovering the genes and enzymes that are involved in aflatoxin formation and genetic regulation. We cloned most, if not all, of the aflatoxin pathway genes. A consensus gene cluster for aflatoxin biosynthesis was discovered in 2005. The factors that affect aflatoxin formation have been studied. In this report, the author summarized the current status of research progress and future possibilities that may be used for solving aflatoxin contamination.
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Affiliation(s)
- Jiujiang Yu
- Southern Regional Research Center, Agricultural Research Service, United States Department of Agriculture (USDA/ARS), New Orleans, LA 70112, USA.
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44
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Kumeda Y, Asao T, Takahashi H, Ichinoe M. High prevalence of B and G aflatoxin-producing fungi in sugarcane field soil in Japan: heteroduplex panel analysis identifies a new genotype within Aspergillus Section Flavi and Aspergillus nomius. FEMS Microbiol Ecol 2012; 45:229-38. [PMID: 19719592 DOI: 10.1016/s0168-6496(03)00154-5] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022] Open
Abstract
Heteroduplex panel analysis (HPA) was previously developed for genetic identification of Aspergillus Section Flavi strains, utilizing polymerase chain reaction-amplified fragments of the internal transcribed spacer (ITS) regions of the rRNA gene. Application of HPA to a field study demonstrated that a new type of FP-1 strains belonging to Section Flavi is predominantly distributed throughout sugarcane field soil in the southernmost islands of Japan, and such a trend may also be the case in Vietnam. All of the 71 tested isolates of type FP-1 were able to produce aflatoxins B and G. The morphological observations of the type FP-1 isolates showed that a major part of them had broad interfaces with Aspergillus parasiticus and the remainder with Aspergillus flavus. Phylogenetic analysis based on the ITS sequences indicated that type FP-1 formed an independent clade positioned between A. parasiticus and A. flavus, and was more closely related to the former species. This is also the first report on the distribution of Aspergillus nomius in sugarcane field soil and/or sugarcane stems in Japan and Vietnam.
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Affiliation(s)
- Yuko Kumeda
- Osaka Prefectural Institute of Public Health, Nakamichi, Osaka 537-0025, Japan.
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45
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Niknejad F, Zaini F, Faramarzi MA, Amini M, Kordbacheh P, Mahmoudi M, Safara M. Candida parapsilosis as a Potent Biocontrol Agent against Growth and Aflatoxin Production by Aspergillus Species. IRANIAN JOURNAL OF PUBLIC HEALTH 2012; 41:72-80. [PMID: 23308351 PMCID: PMC3494234] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Subscribe] [Scholar Register] [Received: 02/28/2012] [Accepted: 08/15/2012] [Indexed: 11/01/2022]
Abstract
BACKGROUND Aflatoxin contamination of food and feed stuff is a serious health problem and significant economic concerns. In the present study, the inhibitory effect of Candida parapsilosis IP1698 on mycelial growth and aflatoxin production in aflatoxigenic strains of Aspergillus species was investigated. METHODS Mycelial growth inhibitions of nine strains of aflatoxigenic and non-aflatoxigenic Aspergillus species in the presence of C. parapsilosis investigated by pour plate technique at different pH, temperature and time of incubation. Reduction of aflatoxin was evaluated in co-cultured fungi in yeast extract sucrose broth after seven days of incubation using HPLC method. The data were analyzed by SPSS 11.5. RESULTS The presence of the C. parapsilosis at different pH did not affect significantly the growth rate of Aspergillus isolates. On the other hand, temperature and time of incubation showed to be significantly effective when compared to controls without C. parapsilosis (P≤0.05). In aflatoxigenic strains, minimum percentage of reductions in total aflatoxin and B1, B2, G1, G2 fractions were 92.98, 92.54, 77.48, 54.54 and 72.22 and maximum percentage of reductions were 99.59, not detectable, 94.42, and not detectable in both G1 and G2, respectively. CONCLUSION C. parapsilosis might employ as a good biocontrol agent against growth and aflatoxin production by aflatoxigenic Aspergillus species.
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Affiliation(s)
- F Niknejad
- Dept. of Medical Mycology and Parasitology, School of Public Health, Tehran University of Medical Sciences, Iran,Corresponding Author: Tel: +98-21-88951585; E-mail
| | - F Zaini
- Dept. of Medical Mycology and Parasitology, School of Public Health, Tehran University of Medical Sciences, Iran
| | - MA Faramarzi
- Dept. of Pharmaceutical Biotechnology, School of Pharmacy and Biotechnology Research Center, Tehran University of Medical Sciences, Iran
| | - M Amini
- Dept. of Medicinal Chemistry, School of Pharmacy, Tehran University of Medical Sciences, Tehran, Iran
| | - P Kordbacheh
- Dept. of Medical Mycology and Parasitology, School of Public Health, Tehran University of Medical Sciences, Iran
| | - M Mahmoudi
- Dept. of Epidemiology and Biostatistics, School of Public Health, Tehran University of Medical Sciences, Iran
| | - M Safara
- Dept. of Medical Mycology and Parasitology, School of Public Health, Tehran University of Medical Sciences, Iran
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Rodrigues P, Santos C, Venâncio A, Lima N. Species identification of Aspergillus section Flavi isolates from Portuguese almonds using phenotypic, including MALDI-TOF ICMS, and molecular approaches. J Appl Microbiol 2011; 111:877-92. [DOI: 10.1111/j.1365-2672.2011.05116.x] [Citation(s) in RCA: 68] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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Yildirim K, Uzuner A, Gulcuoglu EY. Baeyer–Villiger oxidation of some steroids by Aspergillus tamarii MRC 72400. ACTA ACUST UNITED AC 2011. [DOI: 10.1135/cccc2011008] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
Biotransformations of epiandrosterone (1), dehydroepiandrosterone (2), testosterone (3), progesterone (4) and pregnenolone (5) byAspergillus tamariiMRC 72400 for 5 days have been reported and the results of these incubations have been compared with previously published data obtained withAspergillus tamariiQM 1223.A. tamariiMRC 72400 showed higher Bayer–Villiger monooxygenase activities thanA. tamariiQM 1223 did. Apart from pregnenolone (5),A. tamariiMRC 72400 metabolized these steroids in different ways. Incubation of epiandrosterone (1) afforded 3β,11β-dihydroxy-5α-androstan-17-one (6) (3%) and 3β-hydroxy-17a-oxa-D-homo-5α-androstan-17-one (7) (9.5%). Incubation of dehydroepiandrosterone (2) afforded 3β-hydroxy-17a-oxa-D-homoandrost-5-en-17-one (8) (28%), testolactone (9) (6%), 3β,7β-dihydroxyandrost-5-en-17-one (10) (13%) and 3β,7α-dihydroxy- androst-5-en-17-one (11) (24%). Incubation of testosterone (3) afforded testolactone (9) (58%). Incubation of progesterone (4) also afforded testolactone (9), however in higher yield (86%). Incubation of pregnenolone (5) afforded 3β-hydroxy-17a-oxa-D-homoandrost-5-en-17-one (8) (25%) and testolactone (9) (27%).
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Sheijooni-Fumani N, Hassan J, Yousefi SR. Determination of aflatoxin B1 in cereals by homogeneous liquid-liquid extraction coupled to high performance liquid chromatography-fluorescence detection. J Sep Sci 2011; 34:1333-7. [DOI: 10.1002/jssc.201000882] [Citation(s) in RCA: 71] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2010] [Revised: 03/03/2011] [Accepted: 03/03/2011] [Indexed: 11/12/2022]
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Rank C, Nielsen KF, Larsen TO, Varga J, Samson RA, Frisvad JC. Distribution of sterigmatocystin in filamentous fungi. Fungal Biol 2011; 115:406-20. [PMID: 21530923 DOI: 10.1016/j.funbio.2011.02.013] [Citation(s) in RCA: 87] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2010] [Revised: 01/28/2011] [Accepted: 02/16/2011] [Indexed: 10/18/2022]
Abstract
During the last 50y, the carcinogenic mycotoxin sterigmatocystin (ST) has been reported in several phylogenetically and phenotypically different genera: Aschersonia, Aspergillus, Bipolaris, Botryotrichum, Chaetomium, Emericella, Eurotium, Farrowia, Fusarium, Humicola, Moelleriella, Monocillium and Podospora. We have reexamined all available strains of the original producers, in addition to ex type and further strains of each species reported to produce ST and the biosynthetically derived aflatoxins. We also screened strains of all available species in Penicillium and Aspergillus for ST and aflatoxin. Six new ST producing fungi were discovered: Aspergillus asperescens, Aspergillus aureolatus, Aspergillus eburneocremeus, Aspergillus protuberus, Aspergillus tardus, and Penicillium inflatum and one new aflatoxin producer: Aspergillus togoensis (=Stilbothamnium togoense). ST was confirmed in 23 Emericella, four Aspergillus, five Chaetomium, one Botryotrichum and one Humicola species grown on a selection of secondary metabolite inducing media, and using multiple detection methods: HPLC-UV/Vis DAD, - HRMS and - MS/MS. The immediate precursor for aflatoxin, O-methylsterigmatocystin was found in Chaetomium cellulolyticum, Chaetomium longicolleum, Chaetomium malaysiense and Chaetomium virescens, but aflatoxin was not detected from any Chaetomium species. In all 55 species, representing more than 11 clades throughout the Pezizomycotina, can be reliably claimed to be ST producers and 13 of these can also produce aflatoxins. It is not known yet whether the ST/aflatoxin pathway has been developed independently 11 times, or is the result of partial horizontal gene transfer.
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Affiliation(s)
- Christian Rank
- Technical University of Denmark, Department of Systems Biology, Center for Microbial Biotechnology, Søltofts Plads Building 221, DK-2800 Kongens Lyngby, Denmark
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Yabe K, Matsushima K, Koyama T, Hamasaki T. Purification and Characterization of O-Methyltransferase I Involved in Conversion of Demethylsterigmatocystin to Sterigmatocystin and of Dihydrodemethylsterigmatocystin to Dihydrosterigmatocystin during Aflatoxin Biosynthesis. Appl Environ Microbiol 2010; 64:166-71. [PMID: 16349476 PMCID: PMC124688 DOI: 10.1128/aem.64.1.166-171.1998] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
O-Methyltransferase I, which catalyzes conversions both of demethylsterigmatocystin (DMST) to sterigmatocystin (ST) and of dihydrodemethylsterigmatocystin (DHDMST) to dihydrosterigmatocystin (DHST) during aflatoxin biosynthesis, was purified to apparent homogeneity from the cytosol fraction of the mycelia of Aspergillus parasiticus NIAH-26 through the following chromatography series: phenyl-Sepharose, DEAE-Sepharose, phenyl-Sepharose, Sephacryl S-300, and Matrex gel Green A. The apparent molecular mass was estimated at 150 kDa based on Sephacryl S-300 gel filtration chromatography, and the denaturing molecular mass was 43 kDa based on sodium dodecyl sulfate-polyacrylamide gel electrophoresis. The pI of the enzyme was 4.4, and the optimal pH for activity was broad, from 6.5 to 9.0. In competition experiments using the purified enzyme, the formation of ST from DMST was suppressed when DHDMST was added to the reaction mixture and DHST was newly formed. These results indicate that DMST and DHDMST commonly serve as substrates for the enzyme. The K(m) of the enzyme for DMST was 0.94 muM, and that for DHDMST was 2.5 muM. Interestingly, MT-I kinetics deviated substantially from standard Michaelis-Menten kinetics, demonstrating substrate inhibition at a higher substrate concentration.
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Affiliation(s)
- K Yabe
- National Institute of Animal Health, Tsukuba, Ibaraki 305, and Faculty of Agriculture, Tottori University, Tottori 680, Japan
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