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Aflatoxin contamination is caused by Aspergillus flavus and closely related fungi. In The Gambia, aflatoxin contamination of groundnut and maize, two staple and economically important crops, is common. Groundnut and maize consumers are chronically exposed to aflatoxins, sometimes at alarming levels, and this has severe consequences on their health and productivity. Aflatoxin contamination also impedes commercialization in local and international premium markets. In neighboring Senegal, an aflatoxin biocontrol product containing four atoxigenic isolates of A. flavus, Aflasafe SN01, has been registered and is approved for commercial use in groundnut and maize. We detected that the four genotypes composing Aflasafe SN01 are also native to The Gambia. The biocontrol product was tested during two years in 129 maize and groundnut fields and compared with corresponding untreated fields cropped by smallholder farmers in The Gambia. Treated crops contained up to 100% less aflatoxins than untreated crops. A large portion of the crops could have been commercialized in premium markets due to the low aflatoxin content (in many cases no detectable aflatoxins), both at harvest and after storage. Substantial aflatoxin reductions were also achieved when commercially produced groundnut received treatment. Here we report for the first time the use and effectiveness of an aflatoxin biocontrol product registered for use in two nations. With the current scale-out and -up efforts of Aflasafe SN01, a large number of farmers, consumers, and traders in The Gambia and Senegal will obtain health, income, and trade benefits. [Formula: see text] Copyright © 2021 The Author(s). This is an open access article distributed under the CC BY 4.0 International license .
Lamine A. Senghor; Alejandro Ortega-Beltran; Joseph Atehnkeng; Patrick Jarju; P. J. Cotty; Ranajit Bandyopadhyay. Aflasafe SN01 is the First Biocontrol Product Approved for Aflatoxin Mitigation in Two Nations, Senegal and The Gambia. Plant Disease 2021, 105, 1461 -1473.
AMA StyleLamine A. Senghor, Alejandro Ortega-Beltran, Joseph Atehnkeng, Patrick Jarju, P. J. Cotty, Ranajit Bandyopadhyay. Aflasafe SN01 is the First Biocontrol Product Approved for Aflatoxin Mitigation in Two Nations, Senegal and The Gambia. Plant Disease. 2021; 105 (5):1461-1473.
Chicago/Turabian StyleLamine A. Senghor; Alejandro Ortega-Beltran; Joseph Atehnkeng; Patrick Jarju; P. J. Cotty; Ranajit Bandyopadhyay. 2021. "Aflasafe SN01 is the First Biocontrol Product Approved for Aflatoxin Mitigation in Two Nations, Senegal and The Gambia." Plant Disease 105, no. 5: 1461-1473.
Aflatoxins are potent Aspergillus mycotoxins that contaminate food and feed, thereby impacting health and trade. Biopesticides with atoxigenic A. flavus as active ingredients are used to reduce aflatoxin contamination in crops. The mechanism of aflatoxin biocontrol is primarily attributed to competitive exclusion but sometimes aflatoxin is reduced by greater amounts than can be explained by displacement of aflatoxin-producing fungi on the crop. Objectives of this study were to 1) evaluate the ability of atoxigenic A. flavus genotypes to degrade aflatoxin B1 (AFB1) and 2) characterize impacts of temperature, time, and nutrient availability on AFB1 degradation by atoxigenic A. flavus. Aflatoxin-contaminated maize was inoculated with atoxigenic isolates in three separate experiments that included different atoxigenic genotypes, temperature, and time as variables. Atoxigenic genotypes varied in aflatoxin degradation, but all degraded AFB1 > 44% after seven days at 30°C. The optimum temperature for AFB1 degradation was 25-30°C which is similar to the optimum range for AFB1 production. In a time-course experiment, atoxigenics degraded 40% of AFB1 within three days, and 80% of aflatoxin was degraded by day 21. Atoxigenic isolates were able to degrade and utilize AFB1 as a sole carbon source in a chemically defined medium, but quantities of AFB1 degraded declined as glucose concentrations increased. Degradation may be an additional mechanism through which atoxigenic A. flavus biocontrol products reduce aflatoxin contamination pre- and/or post-harvest. Thus, selection of optimal atoxigenic active ingredients can include assessment of both competitive ability in agricultural fields and their ability to degrade aflatoxins.
Lourena A Maxwell; Kenneth Callicott; Ranajit Bandyopadhyay; Hillary Laureen Mehl; Marc Joel Orbach; Peter Cotty. Degradation of aflatoxin B1 by atoxigenic Aspergillus flavus biocontrol agents. Plant Disease 2021, 1 .
AMA StyleLourena A Maxwell, Kenneth Callicott, Ranajit Bandyopadhyay, Hillary Laureen Mehl, Marc Joel Orbach, Peter Cotty. Degradation of aflatoxin B1 by atoxigenic Aspergillus flavus biocontrol agents. Plant Disease. 2021; ():1.
Chicago/Turabian StyleLourena A Maxwell; Kenneth Callicott; Ranajit Bandyopadhyay; Hillary Laureen Mehl; Marc Joel Orbach; Peter Cotty. 2021. "Degradation of aflatoxin B1 by atoxigenic Aspergillus flavus biocontrol agents." Plant Disease , no. : 1.
Iron is an essential component for growth and development. Despite relative abundance in the environment, bioavailability of iron is limited due to oxidation by atmospheric oxygen into insoluble ferric iron. Filamentous fungi have developed diverse pathways to uptake and use iron. In the current study, a putative iron utilization gene cluster (IUC) in Aspergillus flavus was identified and characterized. Gene analyses indicate A. flavus may use reductive as well as siderophore-mediated iron uptake and utilization pathways. The ferroxidation and iron permeation process, in which iron transport depends on the coupling of these two activities, mediates the reductive pathway. The IUC identified in this work includes six genes and is located in a highly polymorphic region of the genome. Diversity among A. flavus genotypes is manifested in the structure of the IUC, which ranged from complete deletion to a region disabled by multiple indels. Molecular profiling of A. flavus populations suggests lineage-specific loss of IUC. The observed variation among A. flavus genotypes in iron utilization and the lineage-specific loss of the iron utilization genes in several A. flavus clonal lineages provide insight on evolution of iron acquisition and utilization within Aspergillus section Flavi. The potential divergence in capacity to acquire iron should be taken into account when selecting A. flavus active ingredients for biocontrol in niches where climate change may alter iron availability.
Bishwo N. Adhikari; Kenneth A. Callicott; Peter J. Cotty. Conservation and Loss of a Putative Iron Utilization Gene Cluster among Genotypes of Aspergillus flavus. Microorganisms 2021, 9, 137 .
AMA StyleBishwo N. Adhikari, Kenneth A. Callicott, Peter J. Cotty. Conservation and Loss of a Putative Iron Utilization Gene Cluster among Genotypes of Aspergillus flavus. Microorganisms. 2021; 9 (1):137.
Chicago/Turabian StyleBishwo N. Adhikari; Kenneth A. Callicott; Peter J. Cotty. 2021. "Conservation and Loss of a Putative Iron Utilization Gene Cluster among Genotypes of Aspergillus flavus." Microorganisms 9, no. 1: 137.
Human populations in Kenya are repeatedly exposed to dangerous aflatoxin levels through consumption of contaminated crops. Biocontrol with atoxigenic Aspergillus flavus is an effective method for preventing aflatoxin in crops. Although four atoxigenic A. flavus isolates (C6E, E63I, R7H and R7K) recovered from maize produced in Kenya are registered as active ingredients for a biocontrol product (Aflasafe KE01) directed at preventing contamination, natural distributions of these four genotypes prior to initiation of commercial use have not been reported. Distributions of the active ingredients of KE01 based on haplotypes at 17 SSR loci are reported. Incidences of the active ingredients and closely related haplotypes were determined in soil collected from 629 maize fields in consecutive long and short rains seasons of 2012. The four KE01 haplotypes were among the top ten most frequent. Haplotype H‐1467 of active ingredient R7K was the most frequent and widespread haplotype in both seasons and was detected in the most soils (3.8%). The four KE01 haplotypes each belonged to large clonal groups containing 27–46 unique haplotypes distributed across multiple areas and in 21% of soils. Each of the KE01 haplotypes belonged to a distinct vegetative compatibility group (VCG), and all A. flavus with haplotypes matching a KE01 active ingredient belonged to the same VCG as the matching active ingredient as did all A. flavus haplotypes differing at only one SSR locus. Persistence of the KE01 active ingredients in Kenyan agroecosystems is demonstrated by detection of identical SSR haplotypes six years after initial isolation. The data provide baselines for assessing long‐term influences of biocontrol applications in highly vulnerable production areas of Kenya.
Md‐Sajedul Islam; Kenneth A. Callicott; Charity Mutegi; Ranajit Bandyopadhyay; Peter J. Cotty. Distribution of active ingredients of a commercial aflatoxin biocontrol product in naturally occurring fungal communities across Kenya. Microbial Biotechnology 2020, 14, 1331 -1342.
AMA StyleMd‐Sajedul Islam, Kenneth A. Callicott, Charity Mutegi, Ranajit Bandyopadhyay, Peter J. Cotty. Distribution of active ingredients of a commercial aflatoxin biocontrol product in naturally occurring fungal communities across Kenya. Microbial Biotechnology. 2020; 14 (4):1331-1342.
Chicago/Turabian StyleMd‐Sajedul Islam; Kenneth A. Callicott; Charity Mutegi; Ranajit Bandyopadhyay; Peter J. Cotty. 2020. "Distribution of active ingredients of a commercial aflatoxin biocontrol product in naturally occurring fungal communities across Kenya." Microbial Biotechnology 14, no. 4: 1331-1342.
Aflatoxins (AF) are hepatocarcinogenic metabolites produced by several Aspergillus species. Crop infection by these species results in aflatoxin contamination of cereals, nuts, and spices. Etiology of aflatoxin contamination is complicated by mixed infections of multiple species with similar morphology and aflatoxin profiles. The current study investigates variation in aflatoxin production between two morphologically similar species that co-exist in West Africa, A. aflatoxiformans and A. minisclerotigenes. Consistent distinctions in aflatoxin production during liquid fermentation were discovered between these species. The two species produced similar concentrations of AFB1 in defined media with either urea or ammonium as the sole nitrogen source. However, production of both AFB1 and AFG1 were inhibited (p < 0.001) for A. aflatoxiformans in a yeast extract medium with sucrose. Although production of AFG1 by both species was similar in urea, A. minisclerotigenes produced greater concentrations of AFG1 in ammonium (p = 0.039). Based on these differences, a reliable and convenient assay for differentiating the two species was designed. This assay will be useful for identifying specific etiologic agents of aflatoxin contamination episodes in West Africa and other regions where the two species are sympatric, especially when phylogenetic analyses based on multiple gene segments are not practical.
Pummi Singh; Hillary L. Mehl; Marc J. Orbach; Kenneth A. Callicott; Peter J. Cotty. Phenotypic Differentiation of Two Morphologically Similar Aflatoxin-Producing Fungi from West Africa. Toxins 2020, 12, 656 .
AMA StylePummi Singh, Hillary L. Mehl, Marc J. Orbach, Kenneth A. Callicott, Peter J. Cotty. Phenotypic Differentiation of Two Morphologically Similar Aflatoxin-Producing Fungi from West Africa. Toxins. 2020; 12 (10):656.
Chicago/Turabian StylePummi Singh; Hillary L. Mehl; Marc J. Orbach; Kenneth A. Callicott; Peter J. Cotty. 2020. "Phenotypic Differentiation of Two Morphologically Similar Aflatoxin-Producing Fungi from West Africa." Toxins 12, no. 10: 656.
Contamination of key staples with aflatoxins compromises the quality of food and feed, impedes trade, and negatively affects the health of consumers whereas acute exposure can be fatal. This study used the Contingent Valuation Method (CVM) on a sample of 480 farmers in counties prone to aflatoxin contamination to assess the willingness to pay (WTP) by farmers for Aflasafe KE01, a promising biological control product for the management of aflatoxin contamination of key staples in Kenya, compare its cost with that of a similar product in use in Nigeria, and determine factors likely to affect its adoption. Four hundred and eighty households from four counties identified as aflatoxin hotspots in Kenya were purposively selected and interviewed using a semi-structured questionnaire. The mean WTP per kilogram of Aflasafe KE01, using Contingent Valuation Method in the four counties ranged from Kenya Shillings (Ksh) 113 to 152/kg compared to a cost of Ksh. 130/kg, the price of a similar product, AflasafeTM, in Nigeria. Factors that positively influenced farmers' WTP included information from crop extension services and access to credit. To facilitate the adoption of Aflasafe KE01 or any other biocontrol product in Kenya and elsewhere, there is a need for increased education efforts through extension services to farmers about aflatoxins. Strategies to ensure that the biocontrol product is integrated into the credit scheme of the technological packages to farmers need to be considered.
Bernard Migwi; Charity Mutegi; John Mburu; John Wagacha; Peter Cotty; Ranajit Bandyopadhyay; Victor M. Manyong. Assessment of willingness-to-pay for Aflasafe KE01, a native biological control product for aflatoxin management in Kenya. Food Additives & Contaminants: Part A 2020, 37, 1951 -1962.
AMA StyleBernard Migwi, Charity Mutegi, John Mburu, John Wagacha, Peter Cotty, Ranajit Bandyopadhyay, Victor M. Manyong. Assessment of willingness-to-pay for Aflasafe KE01, a native biological control product for aflatoxin management in Kenya. Food Additives & Contaminants: Part A. 2020; 37 (11):1951-1962.
Chicago/Turabian StyleBernard Migwi; Charity Mutegi; John Mburu; John Wagacha; Peter Cotty; Ranajit Bandyopadhyay; Victor M. Manyong. 2020. "Assessment of willingness-to-pay for Aflasafe KE01, a native biological control product for aflatoxin management in Kenya." Food Additives & Contaminants: Part A 37, no. 11: 1951-1962.
Lactobacillus helveticus FAM22155 was the most efficient among five lactic acid bacteria at removing aflatoxin B1 (AFB1) during solid-state fermentation on wheat bran substrate. The mechanism of removal was explored by comparing different fermentation modes. Liquid fermentation had little effect on the breakdown of AFB1. However, a protein extract from the fermented bran was equally effective at degrading aflatoxin B1 as living cell digestion. After treatment with heat and protease K, the degrading capacity of the protein extract was significantly reduced. Taken together, the observed biotransformation of AFB1 was mainly associated with proteins produced during bran fermentation. Four products of U-[13C17]-AFB1 were found by mass spectrometry, including Ⅱ-1 (C11H10O4), Ⅱ-2 (C11H10O4), III (C15H12O5), and IV (C14H10O4). These products all lack the lactone ring indicating lower toxicity than aflatoxin B1.
Yingchao Zhang; Peng Wang; Qing Kong; Peter J. Cotty. Biotransformation of Aflatoxin B1 by Lactobacillus helviticus FAM22155 in Wheat Bran by Solid-state Fermentation. Food Chemistry 2020, 341, 128180 .
AMA StyleYingchao Zhang, Peng Wang, Qing Kong, Peter J. Cotty. Biotransformation of Aflatoxin B1 by Lactobacillus helviticus FAM22155 in Wheat Bran by Solid-state Fermentation. Food Chemistry. 2020; 341 ():128180.
Chicago/Turabian StyleYingchao Zhang; Peng Wang; Qing Kong; Peter J. Cotty. 2020. "Biotransformation of Aflatoxin B1 by Lactobacillus helviticus FAM22155 in Wheat Bran by Solid-state Fermentation." Food Chemistry 341, no. : 128180.
Aflatoxins are highly toxic carcinogens that detrimentally influence profitability of agriculture and the health of humans and domestic animals. Several phylogenetically distinct fungi within Aspergillus section Flavi have S-morphology (average sclerotial size < 400 μm), and consistently produce high concentrations of aflatoxins in crops. S-morphology fungi have been implicated as important etiologic agents of aflatoxin contamination in the United States (US), but little is known about the diversity of these fungi. The current study characterized S-morphology fungi (n = 494) collected between 2002 and 2017, from soil and maize samples, in US regions where aflatoxin contamination is a perennial problem. Phylogenetic analyses based on sequences of the calmodulin (1.9 kb) and nitrate reductase (2.1 kb) genes resolved S-morphology isolates from the US into four distinct clades: (1) Aspergillus flavus S-morphotype (89.7%); (2) Aspergillus agricola sp. nov. (2.4%); (3) Aspergillus texensis (2.2%); and (4) Aspergillus toxicus sp. nov. (5.7%). All four S-morphology species produced high concentrations of aflatoxins in maize at 25, 30, and 35°C, but only the A. flavus S-morphotype produced unacceptable aflatoxin concentrations at 40°C. Genetic typing of A. flavus S isolates using 17 simple sequence repeat markers revealed high genetic diversity, with 202 haplotypes from 443 isolates. Knowledge of the occurrence of distinct species and haplotypes of S-morphology fungi that are highly aflatoxigenic under a range of environmental conditions may provide insights into the etiology, epidemiology, and management of aflatoxin contamination in North America.
Pummi Singh; Kenneth A. Callicott; Marc J. Orbach; Peter J. Cotty. Molecular Analysis of S-morphology Aflatoxin Producers From the United States Reveals Previously Unknown Diversity and Two New Taxa. Frontiers in Microbiology 2020, 11, 1236 .
AMA StylePummi Singh, Kenneth A. Callicott, Marc J. Orbach, Peter J. Cotty. Molecular Analysis of S-morphology Aflatoxin Producers From the United States Reveals Previously Unknown Diversity and Two New Taxa. Frontiers in Microbiology. 2020; 11 ():1236.
Chicago/Turabian StylePummi Singh; Kenneth A. Callicott; Marc J. Orbach; Peter J. Cotty. 2020. "Molecular Analysis of S-morphology Aflatoxin Producers From the United States Reveals Previously Unknown Diversity and Two New Taxa." Frontiers in Microbiology 11, no. : 1236.
In warm regions, agricultural fields are occupied by complex Aspergillus flavus communities composed of isolates in many vegetative compatibility groups (VCGs) with varying abilities to produce highly toxic, carcinogenic aflatoxins. Aflatoxin contamination is reduced with biocontrol products that enable atoxigenic isolates from atoxigenic VCGs to dominate the population. Shifts in VCG frequencies similar to those caused by the introduction of biocontrol isolates were detected in Sonora, Mexico, where biocontrol is not currently practiced. The shifts were attributed to founder events. Although VCGs reproduce clonally, significant diversity exists within VCGs. Simple sequence repeat (SSR) fingerprinting revealed that increased frequencies of VCG YV150 involved a single haplotype. This is consistent with a founder event. Additionally, great diversity was detected among 82 YV150 isolates collected over 20 years across Mexico and the United States. Thirty-six YV150 haplotypes were separated into two populations by Structure and SplitsTree analyses. Sixty-five percent of isolates had MAT1-1 and belonged to one population. The remaining had MAT1-2 and belonged to the second population. SSR alleles varied within populations, but recombination between populations was not detected despite co-occurrence at some locations. Results suggest that YV150 isolates with opposite mating-type have either strongly restrained or lost sexual reproduction among themselves.
Alejandro Ortega‐Beltran; Kenneth A. Callicott; Peter J. Cotty. Founder events influence structures of Aspergillus flavus populations. Environmental Microbiology 2020, 22, 3522 -3534.
AMA StyleAlejandro Ortega‐Beltran, Kenneth A. Callicott, Peter J. Cotty. Founder events influence structures of Aspergillus flavus populations. Environmental Microbiology. 2020; 22 (8):3522-3534.
Chicago/Turabian StyleAlejandro Ortega‐Beltran; Kenneth A. Callicott; Peter J. Cotty. 2020. "Founder events influence structures of Aspergillus flavus populations." Environmental Microbiology 22, no. 8: 3522-3534.
Aflatoxins pose significant food security and public health risks, decrease productivity and profitability of animal industries, and hamper trade. To minimize aflatoxin contamination in several crops, a biocontrol technology based on atoxigenic strains of Aspergillus flavus is commercially used in the United States and some African countries. Significant efforts are underway to popularize the use of biocontrol in Africa by various means including incentives. The purpose of this study was to develop quantitative pyrosequencing assays for rapid, simultaneous quantification of proportions of four A. flavus biocontrol genotypes within complex populations of A. flavus associated with maize crops in Nigeria to facilitate payment of farmer incentives for Aflasafe (a biocontrol product) use. Protocols were developed to confirm use of Aflasafe by small scale farmers in Nigeria. Nested PCR amplifications followed by sequence by synthesis pyrosequencing assays were required to quantify frequencies of the active ingredients and, in so doing, confirm successful use of biocontrol by participating farmers. The entire verification process could be completed in 3–4 days proving a savings over other monitoring methods in both time and costs and providing data in a time frame that could work with the commercial agriculture scheme. Quantitative pyrosequencing assays represent a reliable tool for rapid detection, quantification, and monitoring of multiple A. flavus genotypes within complex fungal communities, satisfying the requirements of the regulatory community and crop end-users that wish to determine which purchased crops were treated with the biocontrol product. Techniques developed in the current study can be modified for monitoring other crop-associated fungi.
Kenneth C. Shenge; Bishwo N. Adhikari; Adebowale Akande; Kenneth A. Callicott; Joseph Atehnkeng; Alejandro Ortega-Beltran; P. Lava Kumar; Ranajit Bandyopadhyay; Peter J. Cotty. Monitoring Aspergillus flavus Genotypes in a Multi-Genotype Aflatoxin Biocontrol Product With Quantitative Pyrosequencing. Frontiers in Microbiology 2019, 10, 2529 .
AMA StyleKenneth C. Shenge, Bishwo N. Adhikari, Adebowale Akande, Kenneth A. Callicott, Joseph Atehnkeng, Alejandro Ortega-Beltran, P. Lava Kumar, Ranajit Bandyopadhyay, Peter J. Cotty. Monitoring Aspergillus flavus Genotypes in a Multi-Genotype Aflatoxin Biocontrol Product With Quantitative Pyrosequencing. Frontiers in Microbiology. 2019; 10 ():2529.
Chicago/Turabian StyleKenneth C. Shenge; Bishwo N. Adhikari; Adebowale Akande; Kenneth A. Callicott; Joseph Atehnkeng; Alejandro Ortega-Beltran; P. Lava Kumar; Ranajit Bandyopadhyay; Peter J. Cotty. 2019. "Monitoring Aspergillus flavus Genotypes in a Multi-Genotype Aflatoxin Biocontrol Product With Quantitative Pyrosequencing." Frontiers in Microbiology 10, no. : 2529.
In warm agricultural areas across the globe, maize, groundnut, and other crops become frequently contaminated with aflatoxins produced primarily by the fungus Aspergillus flavus. Crop contamination with those highly toxic and carcinogenic compounds impacts both human and animal health, as well as the income of farmers and trade. In Nigeria, poultry productivity is hindered by high prevalence of aflatoxins in feeds. A practical solution to decrease crop aflatoxin content is to use aflatoxin biocontrol products based on non-toxin-producing strains of A. flavus. The biocontrol product Aflasafe® was registered in 2014 for use in maize and groundnut grown in Nigeria. Its use allows the production of aflatoxin-safe maize and groundnut. A portion of the maize treated with Aflasafe in Nigeria is being used to manufacture feeds used by the poultry industry, and productivity is improving. One of the conditions to register Aflasafe with the national regulator was to demonstrate both the safety of Aflasafe-treated maize to avian species and the impact of Aflasafe as a public good. Results presented here demonstrate that the use of maize colonized by an atoxigenic strain of Aflasafe resulted in superior (p < 0.05) broiler performance in all evaluated parameters in comparison to broilers fed with toxigenic maize. Use of an aflatoxin-sequestering agent (ASA) was not sufficient to counteract the harmful effects of aflatoxins. Both the safety and public good value of Aflasafe were demonstrated during our study. In Nigeria, the availability of aflatoxin-safe crops as a result of using Aflasafe allows poultry producers to improve their productivity, their income, and the health of consumers of poultry products.
M. O. Samuel Aikore; Alejandro Ortega-Beltran; Daisy Eruvbetine; Joseph Atehnkeng; Titilayo D. O. Falade; Peter J. Cotty; Ranajit Bandyopadhyay. Performance of Broilers Fed with Maize Colonized by Either Toxigenic or Atoxigenic Strains of Aspergillus flavus with and without an Aflatoxin-Sequestering Agent. Toxins 2019, 11, 565 .
AMA StyleM. O. Samuel Aikore, Alejandro Ortega-Beltran, Daisy Eruvbetine, Joseph Atehnkeng, Titilayo D. O. Falade, Peter J. Cotty, Ranajit Bandyopadhyay. Performance of Broilers Fed with Maize Colonized by Either Toxigenic or Atoxigenic Strains of Aspergillus flavus with and without an Aflatoxin-Sequestering Agent. Toxins. 2019; 11 (10):565.
Chicago/Turabian StyleM. O. Samuel Aikore; Alejandro Ortega-Beltran; Daisy Eruvbetine; Joseph Atehnkeng; Titilayo D. O. Falade; Peter J. Cotty; Ranajit Bandyopadhyay. 2019. "Performance of Broilers Fed with Maize Colonized by Either Toxigenic or Atoxigenic Strains of Aspergillus flavus with and without an Aflatoxin-Sequestering Agent." Toxins 11, no. 10: 565.
Wild fruits are an important food and income source for many households in Zambia. Non-cultivated plants may be as susceptible as crops to aflatoxin contamination. Concentrations of aflatoxins in commonly consumed wild fruits from markets and characteristics of associated aflatoxin-producers need to be determined to assess the aflatoxin risk posed by handling, processing, storage, and consumption. Samples of Schinziophyton rautanenii (n = 22), Vangueriopsis lanciflora (n = 7), Thespesia garckeana (n = 17), Parinari curatellifolia (n = 17), Ziziphus spp. (n = 10), Adansonia digitata (n = 9), and Tamarindus indica (n = 23) were assayed for aflatoxin using lateral-flow immunochromatography from 2016 to 2017. Aflatoxins were above Zambia’s regulatory limit (10 μg/kg) in S. rautanenii (average = 57 μg/kg), V. lanciflora (average = 12 μg/kg), and T. garckeana (average = 11 μg/kg). The L strain morphotype of Aspergillus flavus was the most frequent member of Aspergillus section Flavi in market samples, although Aspergillus parasiticus and fungi with S morphology were also found. All fruits except T. indica supported both growth (mean = 3.1 × 108 CFU/g) and aflatoxin production (mean = 35,375 μg/kg) by aflatoxigenic Aspergillus section Flavi. Innate resistance to aflatoxin producers was displayed by T. indica. For the other fruits, environment and infecting fungi appeared to have the greatest potential to influence aflatoxin concentrations in markets. This is the first report of aflatoxins and aflatoxin-producers on native fruits in Zambia and suggests mitigation is required.
Paul W. Kachapulula; Ranajit Bandyopadhyay; Peter J. Cotty. Aflatoxin Contamination of Non-cultivated Fruits in Zambia. Frontiers in Microbiology 2019, 10, 1840 .
AMA StylePaul W. Kachapulula, Ranajit Bandyopadhyay, Peter J. Cotty. Aflatoxin Contamination of Non-cultivated Fruits in Zambia. Frontiers in Microbiology. 2019; 10 ():1840.
Chicago/Turabian StylePaul W. Kachapulula; Ranajit Bandyopadhyay; Peter J. Cotty. 2019. "Aflatoxin Contamination of Non-cultivated Fruits in Zambia." Frontiers in Microbiology 10, no. : 1840.
Across sub-Saharan Africa, chili peppers are fundamental ingredients of many traditional dishes. However, chili peppers may contain unsafe aflatoxin concentrations produced by Aspergillus section Flavi fungi. Aflatoxin levels were determined in chili peppers from three states in Nigeria. A total of 70 samples were collected from farmers’ stores and local markets. Over 25% of the samples contained unsafe aflatoxin concentrations. The chili peppers were associated with both aflatoxin producers and atoxigenic Aspergillus flavus genotypes. Efficacy of an atoxigenic biocontrol product, Aflasafe, registered in Nigeria for use on maize and groundnut, was tested for chili peppers grown in three states. Chili peppers treated with Aflasafe accumulated significantly less aflatoxins than nontreated chili peppers. The results suggest that Aflasafe is a valuable tool for the production of safe chili peppers. Use of Aflasafe in chili peppers could reduce human exposure to aflatoxins and increase chances to commercialize chili peppers in premium local and international markets. This is the first report of the efficacy of any atoxigenic biocontrol product for controlling aflatoxin in a spice crop.
Chibundu N. Ezekiel; Alejandro Ortega-Beltran; Eniola O. Oyedeji; Joseph Atehnkeng; Philip Kössler; Folasade Tairu; Irmgard Hoeschle-Zeledon; Petr Karlovsky; Peter J. Cotty; Ranajit Bandyopadhyay. Aflatoxin in Chili Peppers in Nigeria: Extent of Contamination and Control Using Atoxigenic Aspergillus flavus Genotypes as Biocontrol Agents. Toxins 2019, 11, 429 .
AMA StyleChibundu N. Ezekiel, Alejandro Ortega-Beltran, Eniola O. Oyedeji, Joseph Atehnkeng, Philip Kössler, Folasade Tairu, Irmgard Hoeschle-Zeledon, Petr Karlovsky, Peter J. Cotty, Ranajit Bandyopadhyay. Aflatoxin in Chili Peppers in Nigeria: Extent of Contamination and Control Using Atoxigenic Aspergillus flavus Genotypes as Biocontrol Agents. Toxins. 2019; 11 (7):429.
Chicago/Turabian StyleChibundu N. Ezekiel; Alejandro Ortega-Beltran; Eniola O. Oyedeji; Joseph Atehnkeng; Philip Kössler; Folasade Tairu; Irmgard Hoeschle-Zeledon; Petr Karlovsky; Peter J. Cotty; Ranajit Bandyopadhyay. 2019. "Aflatoxin in Chili Peppers in Nigeria: Extent of Contamination and Control Using Atoxigenic Aspergillus flavus Genotypes as Biocontrol Agents." Toxins 11, no. 7: 429.
The authors wish to make the following correction to their paper
Antonio Mauro; Esther Garcia-Cela; Amedeo Pietri; Peter J. Cotty; Paola Battilani. Correction: Mauro, A., et al. Biological Control Products for Aflatoxin Prevention in Italy: Commercial Field Evaluation of Atoxigenic Aspergillus flavus Active Ingredients. Toxins 2018, 10, 30. Toxins 2019, 11, 117 .
AMA StyleAntonio Mauro, Esther Garcia-Cela, Amedeo Pietri, Peter J. Cotty, Paola Battilani. Correction: Mauro, A., et al. Biological Control Products for Aflatoxin Prevention in Italy: Commercial Field Evaluation of Atoxigenic Aspergillus flavus Active Ingredients. Toxins 2018, 10, 30. Toxins. 2019; 11 (2):117.
Chicago/Turabian StyleAntonio Mauro; Esther Garcia-Cela; Amedeo Pietri; Peter J. Cotty; Paola Battilani. 2019. "Correction: Mauro, A., et al. Biological Control Products for Aflatoxin Prevention in Italy: Commercial Field Evaluation of Atoxigenic Aspergillus flavus Active Ingredients. Toxins 2018, 10, 30." Toxins 11, no. 2: 117.
Aflatoxins are carcinogenic metabolites produced primarily by fungi within Aspergillus section Flavi. These fungi infect a wide range of crops in warm regions. Molecular phylogenetic analyses of fungi with S morphology (average sclerotium size < 400 µm) within section Flavi collected from across the United States (US) resulted in the discovery of a novel aflatoxin-producing species, Aspergillus texensis. Aspergillus texensis was isolated from maize grown in Arkansas, Louisiana, and Texas, and from soils cropped to maize in Texas. Aspergillus texensis produces sparse conidia and abundant sclerotia on various culture media, and on maize. Physiological studies have revealed optimal growth on culture media at 35 °C. All isolates of A. texensis produced B and G aflatoxins, cyclopiazonic acid and aspergillic acid. Aspergillus texensis and A. flavus S strain morphotypes produced similar concentrations of total aflatoxins on maize (p > 0.05). Phylogenetic analyses of aflatoxin-producers based on partial gene sequences of the β-tubulin (0.9 kb), calmodulin (1.2 kb), and nitrate reductase (2.1 kb) genes placed A. texensis in a highly supported monophyletic clade closely related to A. minisclerotigenes and a previously reported unnamed lineage designated Lethal Aflatoxicosis Fungus.
Pummi Singh; Marc J. Orbach; Peter J. Cotty. Aspergillus texensis: A Novel Aflatoxin Producer with S Morphology from the United States. Toxins 2018, 10, 513 .
AMA StylePummi Singh, Marc J. Orbach, Peter J. Cotty. Aspergillus texensis: A Novel Aflatoxin Producer with S Morphology from the United States. Toxins. 2018; 10 (12):513.
Chicago/Turabian StylePummi Singh; Marc J. Orbach; Peter J. Cotty. 2018. "Aspergillus texensis: A Novel Aflatoxin Producer with S Morphology from the United States." Toxins 10, no. 12: 513.
Aflatoxins are toxic carcinogens produced by several species of Aspergillus section Flavi, with some aflatoxin producers associated with specific crops. Red chilies (Capsicum spp.) are grown in warm regions that also favor aflatoxin-producers. Aflatoxins in red chilies may result in serious health concerns and severe economic losses. The current study sought to gain insight on causal agents of aflatoxin contamination in red chilies. Naturally contaminated chilies from markets in Nigeria (n = 55) and the United States (US) (n = 169) were examined. The A. flavus L strain was the predominant member of Aspergillus section Flavi (84%) in chilies. Highly toxigenic fungi with S strain morphology were also detected in chilies from both countries (11%), followed by A. tamarii (4.6%) and A. parasiticus (0.4%). Fungi with L morphology produced significantly lower quantities of aflatoxins (mean = 43 μg g−1) compared to S morphology fungi (mean = 667 μg g−1; p < 0.01) in liquid fermentation. Eighty-one percent of S morphology fungi from chilies in US markets produced only B aflatoxins, whereas 20%, all imported from Nigeria, produced both B and G aflatoxins; all S morphology fungi from Nigerian chilies produced both B and G aflatoxins. Multi-gene phylogenetic analyses of partial gene sequences for nitrate reductase (niaD, 2.1 kb) and the aflatoxin pathway transcription factor (aflR, 1.9 kb) resolved Aspergilli recovered from chilies into five highly supported distinct clades: 1) A. parasiticus; 2) A. flavus with either L or S morphology; 3) A. minisclerotigenes; 4) previously reported unnamed taxon SBG erected as A. occiafricanus sp. nov., and 5) a novel taxon erected as A. cicutus sp. nov. Aspergillus cicutus and A. occiafricanus produced the highest concentrations of total aflatoxins in chilies, whereas A. flavus L strains produced the least. The results suggest etiology of aflatoxin contamination of chili is complex and may vary with region. Knowledge of causal agents of aflatoxin contamination of chilies will be helpful in developing mitigation strategies to prevent human exposure.
Pummi Singh; Peter J. Cotty. Characterization of Aspergilli from dried red chilies (Capsicum spp.): Insights into the etiology of aflatoxin contamination. International Journal of Food Microbiology 2018, 289, 145 -153.
AMA StylePummi Singh, Peter J. Cotty. Characterization of Aspergilli from dried red chilies (Capsicum spp.): Insights into the etiology of aflatoxin contamination. International Journal of Food Microbiology. 2018; 289 ():145-153.
Chicago/Turabian StylePummi Singh; Peter J. Cotty. 2018. "Characterization of Aspergilli from dried red chilies (Capsicum spp.): Insights into the etiology of aflatoxin contamination." International Journal of Food Microbiology 289, no. : 145-153.
Dried insects and fish are important sources of income and dietary protein in Zambia. Some aflatoxin-producing fungi are entomopathogenic and also colonize insects and fish after harvest and processing. Aflatoxins are carcinogenic, immune-suppressing mycotoxins that are frequent food contaminants worldwide. Several species within Aspergillus section Flavi have been implicated as causal agents of aflatoxin contamination of crops in Africa. However, aflatoxin producers associated with dried fish and edible insects in Zambia remain unknown, and aflatoxin concentrations in these foods have been inadequately evaluated. The current study sought to address these data gaps to assess potential human vulnerability through the dried fish and edible insect routes of aflatoxin exposure. Caterpillars (n = 97), termites (n = 4), and dried fish (n = 66) sampled in 2016 and 2017 were assayed for aflatoxin by using lateral flow immunochromatography. Average aflatoxin concentrations exceeded regulatory limits for Zambia (10 μg/kg) in the moth Gynanisa maja (11 μg/kg), the moth Gonimbrasia zambesina (Walker) (12 μg/kg), and the termite Macrotermes falciger (Gerstacker) (24 μg/kg). When samples were subjected to simulated poor storage, aflatoxins increased (P < 0.001) to unsafe levels in caterpillars (mean, 4,800 μg/kg) and fish (Oreochromis) (mean, 23 μg/kg). The L strain morphotype of A. flavus was the most common aflatoxin producer on dried fish (88% of Aspergillus section Flavi), termites (68%), and caterpillars (61%), with the exception of Gynanisa maja, for which A. parasiticus was the most common (44%). Dried fish and insects supported growth (mean, 1.3 × 109 CFU/g) and aflatoxin production (mean, 63,620 μg/kg) by previously characterized toxigenic Aspergillus section Flavi species, although the extent of growth and aflatoxigenicity depended on specific fungus-host combinations. The current study shows the need for proper storage and testing of dried insects and fish before consumption as measures to mitigate human exposure to aflatoxins through consumption in Zambia.
Paul W. Kachapulula; Juliet Akello; Ranajit Bandyopadhyay; Peter J. Cotty. Aflatoxin Contamination of Dried Insects and Fish in Zambia. Journal of Food Protection 2018, 81, 1508 -1518.
AMA StylePaul W. Kachapulula, Juliet Akello, Ranajit Bandyopadhyay, Peter J. Cotty. Aflatoxin Contamination of Dried Insects and Fish in Zambia. Journal of Food Protection. 2018; 81 (9):1508-1518.
Chicago/Turabian StylePaul W. Kachapulula; Juliet Akello; Ranajit Bandyopadhyay; Peter J. Cotty. 2018. "Aflatoxin Contamination of Dried Insects and Fish in Zambia." Journal of Food Protection 81, no. 9: 1508-1518.
Aspergillus flavus has long been considered to be an asexual species. Although a sexual stage was recently reported for this species from in vitro studies, the amount of recombination ongoing in natural populations and the genetic distance across which meiosis occurs is largely unknown. In the current study, genetic diversity, reproduction and evolution of natural A. flavus populations endemic to Kenya were examined. A total of 2744 isolates recovered from 629 maize-field soils across southern Kenya in two consecutive seasons were characterized at 17 SSR loci, revealing high genetic diversity (9-72 alleles/locus and 2140 haplotypes). Clonal reproduction and persistence of clonal lineages predominated, with many identical haplotypes occurring in multiple soil samples and both seasons. Genetic analyses predicted three distinct lineages with linkage disequilibrium and evolutionary relationships among haplotypes within each lineage suggesting mutation-driven evolution followed by clonal reproduction. Low genetic differentiation among adjacent communities reflected frequent short distance dispersal.
Md-Sajedul Islam; Kenneth A. Callicott; Charity Mutegi; Ranajit Bandyopadhyay; Peter J. Cotty. Aspergillus flavus resident in Kenya: High genetic diversity in an ancient population primarily shaped by clonal reproduction and mutation-driven evolution. Fungal Ecology 2018, 35, 20 -33.
AMA StyleMd-Sajedul Islam, Kenneth A. Callicott, Charity Mutegi, Ranajit Bandyopadhyay, Peter J. Cotty. Aspergillus flavus resident in Kenya: High genetic diversity in an ancient population primarily shaped by clonal reproduction and mutation-driven evolution. Fungal Ecology. 2018; 35 ():20-33.
Chicago/Turabian StyleMd-Sajedul Islam; Kenneth A. Callicott; Charity Mutegi; Ranajit Bandyopadhyay; Peter J. Cotty. 2018. "Aspergillus flavus resident in Kenya: High genetic diversity in an ancient population primarily shaped by clonal reproduction and mutation-driven evolution." Fungal Ecology 35, no. : 20-33.
Aflatoxin contamination in maize and groundnut is perennial in Ghana with substantial health and economic burden on the population. The present study examined for the first time the prevalence of aflatoxin contamination in maize and groundnut in major producing regions across three agroecological zones (AEZs) in Ghana. Furthermore, the distribution and aflatoxin-producing potential of Aspergillus species associated with both crops were studied. Out of 509 samples (326 of maize and 183 of groundnut), 35% had detectable levels of aflatoxins. Over 15% of maize and 11% of groundnut samples exceeded the aflatoxin threshold limits set by the Ghana Standards Authority of 15 and 20 ppb, respectively. Mycoflora analyses revealed various species and morphotypes within the Aspergillus section Flavi. A total of 5,083 isolates were recovered from both crops. The L morphotype of Aspergillus flavus dominated communities with 93.3% of the population, followed by Aspergillus spp. with S morphotype (6%), A. tamarii (0.4%), and A. parasiticus (0.3%). Within the L morphotype, the proportion of toxigenic members was significantly (P < 0.05) higher than that of atoxigenic members across AEZs. Observed and potential aflatoxin concentrations indicate that on-field aflatoxin management strategies need to be implemented throughout Ghana. The recovered atoxigenic L morphotype fungi are genetic resources that can be employed as biocontrol agents to limit aflatoxin contamination of maize and groundnut in Ghana. [Formula: see text] Copyright © 2018 The Author(s). This is an open access article distributed under the CC BY 4.0 International license .
D. Agbetiameh; A. Ortega-Beltran; R. T. Awuah; J. Atehnkeng; P. J. Cotty; R. Bandyopadhyay. Prevalence of Aflatoxin Contamination in Maize and Groundnut in Ghana: Population Structure, Distribution, and Toxigenicity of the Causal Agents. Plant Disease 2018, 102, 764 -772.
AMA StyleD. Agbetiameh, A. Ortega-Beltran, R. T. Awuah, J. Atehnkeng, P. J. Cotty, R. Bandyopadhyay. Prevalence of Aflatoxin Contamination in Maize and Groundnut in Ghana: Population Structure, Distribution, and Toxigenicity of the Causal Agents. Plant Disease. 2018; 102 (4):764-772.
Chicago/Turabian StyleD. Agbetiameh; A. Ortega-Beltran; R. T. Awuah; J. Atehnkeng; P. J. Cotty; R. Bandyopadhyay. 2018. "Prevalence of Aflatoxin Contamination in Maize and Groundnut in Ghana: Population Structure, Distribution, and Toxigenicity of the Causal Agents." Plant Disease 102, no. 4: 764-772.
Since 2003, non-compliant aflatoxin concentrations have been detected in maize produced in Italy. The most successful worldwide experiments in aflatoxin prevention resulted from distribution of atoxigenic strains of Aspergillus flavus to displace aflatoxin-producers during crop development. The displacement results in lower aflatoxin concentrations in harvested grain. The current study evaluated in field performances of two atoxigenic strains of A. flavus endemic to Italy in artificially inoculated maize ears and in naturally contaminated maize. Co-inoculation of atoxigenic strains with aflatoxin producers resulted in highly significant reductions in aflatoxin concentrations (>90%) in both years only with atoxigenic strain A2085. The average percent reduction in aflatoxin B1 concentration in naturally contaminated maize fields was 92.3%, without significant differences in fumonisins between treated and control maize. The vegetative compatibility group of A2085 was the most frequently recovered A. flavus in both treated and control plots (average 61.9% and 53.5% of the A. flavus, respectively). A2085 was therefore selected as an active ingredient for biocontrol products and deposited under provisions of the Budapest Treaty in the Belgian Co-Ordinated Collections of Micro-Organisms (BCCM/MUCL) collection (accession MUCL54911). Further work on development of A2085 as a tool for preventing aflatoxin contamination in maize produced in Italy is ongoing with the commercial product named AF-X1™.
Antonio Mauro; Esther Garcia-Cela; Amedeo Pietri; Peter J. Cotty; Paola Battilani. Biological Control Products for Aflatoxin Prevention in Italy: Commercial Field Evaluation of Atoxigenic Aspergillus flavus Active Ingredients. Toxins 2018, 10, 30 .
AMA StyleAntonio Mauro, Esther Garcia-Cela, Amedeo Pietri, Peter J. Cotty, Paola Battilani. Biological Control Products for Aflatoxin Prevention in Italy: Commercial Field Evaluation of Atoxigenic Aspergillus flavus Active Ingredients. Toxins. 2018; 10 (1):30.
Chicago/Turabian StyleAntonio Mauro; Esther Garcia-Cela; Amedeo Pietri; Peter J. Cotty; Paola Battilani. 2018. "Biological Control Products for Aflatoxin Prevention in Italy: Commercial Field Evaluation of Atoxigenic Aspergillus flavus Active Ingredients." Toxins 10, no. 1: 30.