Aspergillus section Flavi diversity and the role of A. novoparasiticus in aflatoxin contamination in the sugarcane production chain

2019 ◽  
Vol 293 ◽  
pp. 17-23 ◽  
Author(s):  
Beatriz Thie Iamanaka ◽  
Aline de Souza Lopes ◽  
Ligia Manoel Martins ◽  
Jens Christian Frisvad ◽  
Angel Medina ◽  
...  
Keyword(s):  
Aflatoxin Contamination ◽  
Production Chain ◽  
Sugarcane Production ◽  
Aspergillus Section Flavi ◽  
Aspergillus Section

scholarly journals Postharvest Practices of Maize Farmers in Kaiti District, Kenya and the Impact of Hermetic Storage on Populations of Aspergillus Spp. and Aflatoxin Contamination

2016 ◽  
Vol 5 (6) ◽  
pp. 53 ◽  
Author(s):  
Angeline W Maina ◽  
John M Wagacha ◽  
Francis B Mwaura ◽  
James W Muthomi ◽  
Charles P Woloshuk
Keyword(s):  
Aflatoxin Contamination ◽  
Effective Management ◽  
Hermetic Storage ◽  
Aflatoxin Content ◽  
Aspergillus Section Flavi ◽  
Triple Layer ◽  
Storage Methods ◽  
The Impact ◽  
And Storage ◽  
Aspergillus Section

Aflatoxin contamination in maize by Aspergillus spp. is a major problem causing food, income and health concerns. A study was carried out in Kaiti District in Lower Eastern Kenya to evaluate the effect of three months storage of maize in triple-layer hermetic (PICS™) bags on the population of Aspergillus spp. and levels of aflatoxin. Postharvest practices by maize farmers including time of harvesting, drying and storage methods were obtained with a questionnaire. Aspergillus spp. in soil and maize were isolated by serial dilution-plating and aflatoxin content was measured using Vicam method. Maize was mostly stored in woven polypropylene (PP) and sisal bags within granaries and living houses. Aspergillus flavus L-strain was the most predominant isolate from soil (Mean = 8.4 x102 CFU/g),on the harvested grain (4.1 x 102 CFU/g) and grain sampled after three months of storage (1.1 x 103 CFU/g). The type of storage bag significantly (P ≤ 0.05) influenced the population of members of Aspergillus section Flavi, with A. flavus (S and L strains) and A. parasiticus being 71% higher in PP bags than in PICS bags. Total aflatoxin in maize sampled at harvest and after three months storage ranged from <5 to 42.7 ppb with 55% lower aflatoxin content in PICS bags than in PP bags. After storage, the population of Aspergillus section Flavi was positively correlated with aflatoxin levels. The results of this study demonstrate that PICS bags are an effective management option for reducing population of toxigenic Aspergillus spp. and aflatoxin in stored maize.

scholarly journals Role of Maize Weevil, Sitophilus zeamais Motsch. on Spread of Aspergillus section flavi in Different Nepalese Maize Varieties

2019 ◽  
Vol 2019 ◽  
pp. 1-5
Author(s):  
K. Bhusal ◽  
D. Khanal
Keyword(s):  
Storage Conditions ◽  
Sitophilus Zeamais ◽  
Maize Weevil ◽  
Aspergillus Section Flavi ◽  
Maize Varieties ◽  
Maize Variety ◽  
Sitophilus Zeamais Motsch ◽  
Aspergillus Section ◽  
Plot Design

Experiments were conducted to find out the role of maize weevil, Sitophilus zeamais Motsch. on spread of green fungus, Aspergillus section flavi, in different varieties of stored maize in laboratory in 2016. Lab experiment was conducted to find the role of weevil on spread of A. flavus on five main varieties of maize grown at Nepal in split plot design, namely, Arun-2, Arun-4, Manakamana-1, Manakamana-3, and Rampur composite with three replications at NAST, Khumaltar, from August to September 2016. One hundred grams of each maize variety was exposed to weevil along with fungus and with fungus only to see the spread of the fungus under presence and absence of weevil. Among the tested five maize varieties, the lowest infestation was observed on Rampur Composite (14.99%) while it was the highest on Manakamana-3 (87.70%). The highest mean infestation (75.58%) was found under weevil released condition while it was lower (62.16%) under nonreleased condition. In presence of weevil, the infestation of the fungus increased and in their absence the infestation was low which signifies the role of weevil in fungal spread. All indices indicate that Rampur composite is the best variety among the five tested varieties in terms of storage under the presence of fungus and weevils. This study also indicates ample scope for further study on different varieties of maize under several storage conditions.

scholarly journals The biodiversity of Aspergillus section Flavi and aflatoxins in the Brazilian peanut production chain

2017 ◽  
Vol 94 ◽  
pp. 101-107 ◽  
Author(s):  
Ligia Manoel Martins ◽  
Anderson S. Sant'Ana ◽  
Maria Helena Pelegrinelli Fungaro ◽  
Josué José Silva ◽  
Maristela da Silva do Nascimento ◽  
...  
Keyword(s):  
Production Chain ◽  
Aspergillus Section Flavi ◽  
Peanut Production ◽  
Aspergillus Section

scholarly journals Aflatoxin Contamination of Dried Insects and Fish in Zambia

2018 ◽  
Vol 81 (9) ◽  
pp. 1508-1518 ◽  
Author(s):  
PAUL W. KACHAPULULA ◽  
JULIET AKELLO ◽  
RANAJIT BANDYOPADHYAY ◽  
PETER J. COTTY
Keyword(s):  
Dietary Protein ◽  
Aflatoxin Production ◽  
Aflatoxin Contamination ◽  
Food Contaminants ◽  
Edible Insect ◽  
Aspergillus Section Flavi ◽  
Regulatory Limits ◽  
Data Gaps ◽  
Dried Fish ◽  
Aspergillus Section

ABSTRACT 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 &lt; 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.

scholarly journals Aspergillus parasiticus Communities Associated with Sugarcane in the Rio Grande Valley of Texas: Implications of Global Transport and Host Association Within Aspergillus Section Flavi

2014 ◽  
Vol 104 (5) ◽  
pp. 462-471 ◽  
Author(s):  
N. P. Garber ◽  
P. J. Cotty
Keyword(s):  
Aspergillus Parasiticus ◽  
Agricultural Soils ◽  
Rio Grande Valley ◽  
Rio Grande ◽  
Aflatoxin Contamination ◽  
Cropping Pattern ◽  
Aspergillus Section Flavi ◽  
Global Transport ◽  
Raw Sugar ◽  
Aspergillus Section

In the Rio Grande Valley of Texas (RGV), values of maize and cottonseed crops are significantly reduced by aflatoxin contamination. Aflatoxin contamination of susceptible crops is the product of communities of aflatoxin producers and the average aflatoxin-producing potentials of these communities influence aflatoxin contamination risk. Cropping pattern influences community composition and, thereby, the epidemiology of aflatoxin contamination. In 2004, Aspergillus parasiticus was isolated from two fields previously cropped to sugarcane but not from 23 fields without recent history of sugarcane cultivation. In 2004 and 2005, A. parasiticus composed 18 to 36% of Aspergillus section Flavi resident in agricultural soils within sugarcane-producing counties. A. parasiticus was not detected in counties that do not produce sugarcane. Aspergillus section Flavi soil communities within sugarcane-producing counties differed significantly dependent on sugarcane cropping history. Fields cropped to sugarcane within the previous 5 years had greater quantities of A. parasiticus (mean = 16 CFU/g) than fields not cropped to sugarcane (mean = 0.1 CFU/g). The percentage of Aspergillus section Flavi composed of A. parasiticus increased to 65% under continuous sugarcane cultivation and remained high the first season of rotation out of sugarcane. Section Flavi communities in fields rotated to non-sugarcane crops for 3 to 5 years were composed of <5% A. parasiticus, and fields with no sugarcane history averaged only 0.2% A. parasiticus. The section Flavi community infecting RGV sugarcane stems ranged from 95% A. parasiticus in billets prepared for commercial planting to 52% A. parasiticus in hand-collected sugarcane stems. Vegetative compatibility assays and multilocus phylogenies verified that aflatoxin contamination of raw sugar was previously attributed to similar A. parasiticus in Japan. Association of closely related A. parasiticus genotypes with sugarcane produced in Japan and RGV, frequent infection of billets by these genotypes, and the ephemeral nature of A. parasiticus in RGV soils suggests global transport with sugarcane planting material.

scholarly journals The Role of Aflatoxins in Aspergillus flavus Resistance to Stress

2021 ◽  
Author(s):  
Massimo Reverberi ◽  
Marzia Beccaccioli ◽  
Marco Zaccaria
Keyword(s):  
Reactive Oxygen Species ◽  
Secondary Metabolites ◽  
Natural Population ◽  
Aspergillus Flavus ◽  
Opportunistic Pathogens ◽  
Aspergillus Section Flavi ◽  
Resistance To Stress ◽  
Niche Competition ◽  
Aspergillus Section

Aspergillus section Flavi produce the aflatoxins, secondary metabolites toxic to humans and animals. Why do these fungi produce aflatoxins? They do not have a clear role in pathogenicity or in niche competition. Aspergillus employs a considerable amount of energy to synthesize them: more than 20 enzymatic catalyzes are needed. Within the A. flavus species, all opportunistic pathogens of maize, more than half of the natural population are atoxigenic, indicating that aflatoxins are not so obviously linked to an enhancement of population fitness. The perspective changes in A. parasiticus, pathogen to peanuts, where more than 90% of the natural population produce the four aflatoxins. In this chapter, we aim to discuss our recent hypothesis that aflatoxins act as antioxidants providing more time to Aspergillus to “escape” an exploited substrate, that in the meanwhile is “fully charged” with reactive oxygen species and oxylipins.

scholarly journals Molecular Characterisation of Aflatoxigenic and Non-Aflatoxigenic Strains of Aspergillus Section Flavi Isolated from Imported Peanuts along the Supply Chain in Malaysia

Toxins ◽  
2019 ◽  
Vol 11 (9) ◽  
pp. 501 ◽  
Author(s):  
Mahror Norlia ◽  
Selamat Jinap ◽  
Mahmud Ab Rashid Nor-Khaizura ◽  
Son Radu ◽  
Cheow Keat Chin ◽  
...  
Keyword(s):  
Aflatoxin Production ◽  
Storage Conditions ◽  
Aflatoxin Contamination ◽  
Aflatoxin Biosynthesis ◽  
Asian Countries ◽  
Aspergillus Section Flavi ◽  
Aflatoxigenic Fungi ◽  
Tropical Weather ◽  
Southeast Asian Countries ◽  
Aspergillus Section

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.

scholarly journals The Role of Fungi in the Cocoa Production Chain and the Challenge of Climate Change

2021 ◽  
Vol 7 (3) ◽  
pp. 202
Author(s):  
Johannes Delgado-Ospina ◽  
Junior Bernardo Molina-Hernández ◽  
Clemencia Chaves-López ◽  
Gianfranco Romanazzi ◽  
Antonello Paparella
Keyword(s):  
Climate Change ◽  
Fungal Infections ◽  
Close Association ◽  
Pathogenic Fungi ◽  
Fungal Species ◽  
Mitigation Strategies ◽  
Plant Diseases ◽  
Production Chain ◽  
Cocoa Production

Background: The role of fungi in cocoa crops is mainly associated with plant diseases and contamination of harvest with unwanted metabolites such as mycotoxins that can reach the final consumer. However, in recent years there has been interest in discovering other existing interactions in the environment that may be beneficial, such as antagonism, commensalism, and the production of specific enzymes, among others. Scope and approach: This review summarizes the different fungi species involved in cocoa production and the cocoa supply chain. In particular, it examines the presence of fungal species during cultivation, harvest, fermentation, drying, and storage, emphasizing the factors that possibly influence their prevalence in the different stages of production and the health risks associated with the production of mycotoxins in the light of recent literature. Key findings and conclusion: Fungi associated with the cocoa production chain have many different roles. They have evolved in a varied range of ecosystems in close association with plants and various habitats, affecting nearly all the cocoa chain steps. Reports of the isolation of 60 genera of fungi were found, of which only 19 were involved in several stages. Although endophytic fungi can help control some diseases caused by pathogenic fungi, climate change, with increased rain and temperatures, together with intensified exchanges, can favour most of these fungal infections, and the presence of highly aggressive new fungal genotypes increasing the concern of mycotoxin production. For this reason, mitigation strategies need to be determined to prevent the spread of disease-causing fungi and preserve beneficial ones.

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