Polyphasic approach to the identification of Aspergillus section Flavi isolated from Brazil nuts

Brazil nut is an Amazonian raw material with a fundamental role in the socioeconomic organization of the extractive areas of the Legal Amazon Brazil's largest socio-geographical division, composed of nine states are part of the Amazon basin. However, due to the precarious conditions of storage and processing, the nut is frequently subjected to contamination by aflatoxigenic fungi. These fungal species have high similarity, which makes it difficult to identify them only by traditional methods. This research had as objective the identification of a species of Aspergillus Flavi isolated from Brazil nut samples, through the polyphase approach. To identify the fungal isolate, macromorphological and micromorphological characterization techniques by microcultive in a slide were used; The molecular identification followed by sequencing compared the nucleotide sequences with the GenBank database, the aflatoxigenic potential of the strain was evaluated by HPLC. According to the results, the macromorphological and micromorphological analysis showed color characteristics and reproductive structures typical of the genus Aspergillus and the Flavi section. However, only from the results of molecular identification in which the strain showed 100% similarity with Aspergillus nomius and the metabolic production profile in which the species was producing the 4 types of aflatoxins (AFG2= 1177,23, AFG1 = 2458, 90, AFB2 = 860,23, AFB1 = 2370,06) it was possible to carry out the correct identification of the fungus as Aspergillus nomius. The combination of different techniques for identification of the strain Aspergillus section Flavi allowed a more accurate characterization. The identification of strain as Aspergillus nomius with aflatoxigenic potential in Brazil nuts confirms the affinity of these microorganisms for this substrate.

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The biodiversity of Aspergillus section Flavi in brazil nuts: From rainforest to consumer

International Journal of Food Microbiology ◽

10.1016/j.ijfoodmicro.2012.10.018 ◽

2013 ◽

Vol 160 (3) ◽

pp. 267-272 ◽

Cited By ~ 34

Author(s):

Thaiane O. Calderari ◽

Beatriz T. Iamanaka ◽

Jens C. Frisvad ◽

John I. Pitt ◽

Daniele Sartori ◽

...

Keyword(s):

Brazil Nuts ◽

Aspergillus Section Flavi ◽

Aspergillus Section

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Use of a polyphasic approach including MALDI-TOF MS for identification of Aspergillus section Flavi strains isolated from food commodities in Brazil

Annals of Microbiology ◽

10.1007/s13213-015-1050-0 ◽

2015 ◽

Vol 65 (4) ◽

pp. 2119-2129 ◽

Cited By ~ 9

Author(s):

Fernanda Chaves da Silva ◽

Sara Maria Chalfoun ◽

Luis Roberto Batista ◽

Cledir Santos ◽

Nelson Lima

Keyword(s):

Polyphasic Approach ◽

Maldi Tof Ms ◽

Aspergillus Section Flavi ◽

Maldi Tof ◽

Food Commodities ◽

Aspergillus Section ◽

Tof Ms

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Polyphasic approach to the identification and characterization of aflatoxigenic strains of Aspergillus section Flavi isolated from peanuts and peanut-based products marketed in Malaysia

International Journal of Food Microbiology ◽

10.1016/j.ijfoodmicro.2018.05.030 ◽

2018 ◽

Vol 282 ◽

pp. 9-15 ◽

Cited By ~ 10

Author(s):

M. Norlia ◽

S. Jinap ◽

M.A.R. Nor-Khaizura ◽

R. Son ◽

C.K. Chin ◽

...

Keyword(s):

Polyphasic Approach ◽

Aspergillus Section Flavi ◽

Identification And Characterization ◽

Aspergillus Section

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A Polyphasic Approach to Compare the Genomic Profiles of Aflatoxigenic and Non-Aflatoxigenic Isolates of Aspergillus Section Flavi

Toxins ◽

10.3390/toxins12010056 ◽

2020 ◽

Vol 12 (1) ◽

pp. 56

Author(s):

Asmaa Abbas ◽

Taha Hussien ◽

Tapani Yli-Mattila

Keyword(s):

Genetic Diversity ◽

Phylogenetic Relationships ◽

Random Amplified Polymorphic Dna ◽

Issr Markers ◽

The Philippines ◽

Polyphasic Approach ◽

Group Method ◽

Aspergillus Section Flavi ◽

Aspergillus Section ◽

Issr Primers

Aflatoxins (AF) are highly toxic compounds produced by Aspergillus section Flavi. They spoil food crops and present a serious global health hazard to humans and livestock. The aim of this study was to examine the phylogenetic relationships among aflatoxigenic and non-aflatoxigenic Aspergillus isolates. A polyphasic approach combining phylogenetic, sequence, and toxin analyses was applied to 40 Aspergillus section Flavi isolates collected from eight countries around the world (USA, Philippines, Egypt, India, Australia, Indonesia, China, and Uganda). This allows one to pinpoint the key genomic features that distinguish AF producing and non-producing isolates. Based on molecular identification, 32 (80%) were identified as A. flavus, three (7.5%) as A. parasiticus, three (7.5%) as A. nomius and one (2.5%) as A. tamarii. Toxin analysis showed that 22 (55%) Aspergillus isolates were aflatoxigenic. The majority of the toxic isolates (62.5%) originated from Egypt. The highest aflatoxin production potential was observed in an A. nomius isolate which is originally isolated from the Philippines. DNA-based molecular markers such as random amplified polymorphic DNA (RAPD) and inter-simple sequence repeats (ISSR) were used to evaluate the genetic diversity and phylogenetic relationships among these 40 Aspergillus isolates, which were originally selected from 80 isolates. The percentage of polymorphic bands in three RAPD and three ISSR primers was 81.9% and 79.37%, respectively. Analysis of molecular variance showed significant diversity within the populations, 92% for RAPD and 85% for ISSR primers. The average of Polymorphism Information Content (PIC), Marker Index (MI), Nei’s gene diversity (H) and Shannon’s diversity index (I) in ISSR markers are higher than those in RAPD markers. Based on banding patterns and gene diversities values, we observed that the ISSR-PCR provides clearer data and is more successful in genetic diversity analyses than RAPD-PCR. Dendrograms generated from UPGMA (Unweighted Pair Group Method with Arithmetic Mean) cluster analyses for RAPD and ISSR markers were related to the geographic origin.

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Monitoring and Determination of Fungi and Mycotoxins in Stored Brazil Nuts

Journal of Food Protection ◽

10.4315/0362-028x.jfp-13-005 ◽

2013 ◽

Vol 76 (8) ◽

pp. 1414-1420 ◽

Cited By ~ 7

Author(s):

ARIANNE COSTA BAQUIÃO ◽

MAITÊ M. M. DE OLIVEIRA ◽

TATIANA A. REIS ◽

PATRÍCIA ZORZETE ◽

DANIELLE D. ATAYDE ◽

...

Keyword(s):

High Performance ◽

Management Practices ◽

Cyclopiazonic Acid ◽

Aflatoxin Production ◽

Brazil Nut ◽

Brazil Nuts ◽

Aspergillus Section Flavi ◽

Penicillium Spp ◽

Aspergillus Section

Brazil nut (Bertholletia excelsa) is an important commodity from the Brazilian Amazon, and approximately 37,000 tons (3.36 × 107 kg) of Brazil nuts are harvested each year. However, substantial nut contamination by Aspergillus section Flavi occurs, with subsequent production of mycotoxins. In this context, the objective of the present investigation was to evaluate the presence of fungi and mycotoxins (aflatoxins and cyclopiazonic acid) in 110 stored samples of cultivated Brazil nut (55 samples of nuts and 55 samples of shells) collected monthly for 11 months in Itacoatiara, State of Amazonas, Brazil. The samples were inoculated in duplicate onto Aspergillus flavus and Aspergillus parasiticus agar and potato dextrose agar for the detection of fungi, and the presence of mycotoxins was determined by high-performance liquid chromatography. The most prevalent fungi in nuts and shells were Aspergillus spp., Fusarium spp., and Penicillium spp. A polyphasic approach was used for identification of Aspergillus species. Aflatoxins and cyclopiazonic acid were not detected in any of the samples analyzed. The low water activity of the substrate was a determinant factor for the presence of fungi and the absence of aflatoxin in Brazil nut samples. The high frequency of isolation of aflatoxigenic Aspergillus section Flavi strains, mainly A. flavus, and their persistence during storage increase the chances of aflatoxin production on these substrates and indicates the need for good management practices to prevent mycotoxin contamination in Brazil nuts.

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Molecular analysis of Aspergillus section Flavi isolated from Brazil nuts

World Journal of Microbiology and Biotechnology ◽

10.1007/s11274-011-0956-3 ◽

2011 ◽

Vol 28 (4) ◽

pp. 1817-1825 ◽

Cited By ~ 23

Author(s):

Juliana Soares Gonçalves ◽

Lara Munique Ferracin ◽

Maria Lucia Carneiro Vieira ◽

Beatriz Thie Iamanaka ◽

Marta Hiromi Taniwaki ◽

...

Keyword(s):

Molecular Analysis ◽

Brazil Nuts ◽

Aspergillus Section Flavi ◽

Aspergillus Section

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A polyphasic approach to the identification of aflatoxigenic and non-aflatoxigenic strains of Aspergillus Section Flavi isolated from Portuguese almonds

International Journal of Food Microbiology ◽

10.1016/j.ijfoodmicro.2008.11.023 ◽

2009 ◽

Vol 129 (2) ◽

pp. 187-193 ◽

Cited By ~ 103

Author(s):

Paula Rodrigues ◽

Armando Venâncio ◽

Zofia Kozakiewicz ◽

Nelson Lima

Keyword(s):

Polyphasic Approach ◽

Aspergillus Section Flavi ◽

Aspergillus Section

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Prevalence of Aspergillus species on selected Colombian animal feedstuffs and ability of Aspergillus section Flavi to produce aflatoxins

World Mycotoxin Journal ◽

10.3920/wmj2008.1041 ◽

2009 ◽

Vol 2 (1) ◽

pp. 31-34 ◽

Cited By ~ 3

Author(s):

G. Diaz ◽

M. Lozano ◽

A. Acuña

Keyword(s):

Liquid Chromatography ◽

Cottonseed Meal ◽

Sunflower Seed ◽

Seed Meal ◽

Aspergillus Section Flavi ◽

Wheat Middlings ◽

Highperformance Liquid Chromatography ◽

Animal Feedstuffs ◽

Aflatoxin B ◽

Aspergillus Section

A total of 57 samples of feedstuffs commonly used for animal nutrition in Colombia (maize, soybean, sorghum, cottonseed meal, sunflower seed meal, wheat middlings and rice) were analysed for Aspergillus contamination. Aspergillus fungi were identified at species level and their ability to produce aflatoxins was determined by highperformance liquid chromatography. A total of 31 of the feedstuffs analysed (54.4%) were found to contain Aspergillus spp. The most contaminated substrate was maize (100%) followed by cottonseed meal (80%), sorghum (60%) and wheat middlings (60%). Soybean showed lower levels of contamination (10%). No Aspergillus spp. could be isolated from rice or sunflower seed meal. Total Aspergillus strains isolated were 50, with 28 belonging to section Flavi (56%), 17 to section Nigri (34%), 4 to section Circumdati (8%) and 1 to section Fumigati (2%). Among section Flavi, 17 isolates were identified as A. flavus, seven as A. parasiticus, two as A. oryzae and two as A. tamarii. Production of aflatoxins by Aspergillus section Flavi was screened by liquid chromatography. About three quarters of the A. flavus strains (76.5%) produced aflatoxin B1 (0.2 to 240.4 µg/g) and aflatoxin B2 (0.2 to 1.6 µg/g), while all A. parasiticus strains produced the four naturally occurring aflatoxins (aflatoxin B1 from 0.6 to 83.5 µg/g, aflatoxin B2 from 0.3 to 4.8 µg/g, aflatoxin G1 from 0.4 to 19.3 µg/g and aflatoxin G2 from 0.1 to 1.0 µg/g). This is the first study demonstrating the presence of highly toxigenic Aspergillus fungi in Colombian animal feedstuffs.

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