Incidence of Aspergillus flavus, Aspergillus parasiticus and aflatoxins in Brazil nuts in the Amazon forest environment

2014 ◽  
Vol 7 (2) ◽  
pp. 199-205 ◽  
Author(s):  
F.M.N. Leite ◽  
Leite de Souza ◽  
J.M.L. de Souza ◽  
C.B. da C. Cartaxo ◽  
V. de S. Álvares ◽  
...  
Keyword(s):  
Water Activity ◽  
Aspergillus Flavus ◽  
Aspergillus Parasiticus ◽  
Amazon Forest ◽  
Forest Environment ◽  
Mean Values ◽  
Brazil Nuts ◽  
Colony Forming Units ◽  
Aflatoxigenic Fungi ◽  
Aflatoxin B

This work aimed to evaluate, in the Amazon Forest environment, the effect of time on contamination of Brazil nuts with Aspergillus flavus, Aspergillus parasiticus and aflatoxins after falling of the pods. Samples were collected at three different times and analysed for water activity, potentially aflatoxigenic fungi A. flavus and A. parasiticus, other fungi and aflatoxins. The mean values for the parameters tested were: water activity 0.98; A. flavus and A. parasiticus 1.3×101 colony forming units (cfu)/g; other fungi 3.2×103 cfu/g; aflatoxin B1 0.073 μg/kg, aflatoxin B2 0.009 μg/kg, aflatoxin G1 0.034 μg/kg and aflatoxin G2 0.007 μg/kg. The incidence of A. flavus and A. parasiticus was not significantly affected by the time, during which the pods were on the forest soil. Moreover, aflatoxins levels were low during the whole study period, suggesting that adverse forest conditions were not the main factor that stimulate the production of aflatoxins.

Aflatoxigenic fungi and aflatoxin B1 in commercial pet food in Brazil

2009 ◽  
Vol 2 (1) ◽  
pp. 85-90 ◽  
Author(s):  
S. Campos ◽  
L. Keller ◽  
L. Cavaglieri ◽  
C. Krüger ◽  
M. Fernández Juri ◽  
...  
Keyword(s):  
Aspergillus Flavus ◽  
Aspergillus Parasiticus ◽  
Storage Conditions ◽  
Pet Food ◽  
Dog Food ◽  
Aflatoxigenic Fungi ◽  
Toxigenic Strains ◽  
Aflatoxin B ◽  
Prevalent Species ◽  
Recommended Level

The aims of this study were to determine the aflatoxigenic mycoflora and the incidence of aflatoxin B1 in commercial samples of ready dog food. This in turn demonstrated the ability of the Aspergillus flavus and Aspergillus parasiticus strains to produce aflatoxin B1. 180 samples (standard, premium and super premium) were collected. Aspergillus was the prevalent genera followed by Penicillium and Fusarium. A. flavus and A. parasiticus were the prevalent species. All A. flavus and A. parasiticus strains from super premium samples were able to produce aflatoxin B1, whereas toxigenic strains isolated from standard and premium samples varied from 80 to 100%. A high percentage of ready pet food contaminated by toxigenic species from section Flavi was found and aflatoxin B1 levels were detected. The fungal counts from the three kinds of feed did not exceed the proposed value (1×104 cfu/g) and none of the samples exceeded the aflatoxin B1 recommended level (20 ng/g). The presence of A. flavus and A. parasiticus with aflatoxigenic ability could be a potential risk for production of AFB1 in feedstuffs when environmental storage conditions are not adequate.

Aflatoxin production by Aspergillus flavus and Aspergillus parasiticus on deoiled ground nyjer seeds

2021 ◽  
Vol 14 (2) ◽  
pp. 213-220
Author(s):  
D. Gizachew ◽  
C.-H. Chang ◽  
B. Szonyi ◽  
W.E. Ting
Keyword(s):  
Water Activity ◽  
Aspergillus Flavus ◽  
Aspergillus Parasiticus ◽  
Animal Feed ◽  
Fungal Growth ◽  
Aflatoxin Production ◽  
Growth Conditions ◽  
Growth Patterns ◽  
Aflatoxin B ◽  
Similar Growth

Nyjer seeds are oil rich (35-40% oil content) seeds of the plant Guizotia abyssinica, which is closely related to sunflower. They are pressed mechanically for cooking oil in Ethiopia and elsewhere. The remaining deoiled cake, which contains approximately 10% oil is commonly used as animal feed. This study investigated the effect of water activity and temperature on the growth and aflatoxin production of the four main forms of aflatoxin (B1, B2, G1 and G2) by Aspergillus flavus and Aspergillus parasiticus on ground nyjer seed with 10% oil. The ground nyjer seeds were adjusted to different water activity aw levels (0.82, 0.86, 0.90, 0.94 and 0.98 aw) and incubated at 20, 27 and 35 °C, up to 30 days. Our results show that A. flavus and A. parasiticus had similar growth patterns in which the slowest fungal growth occurred on ground seeds with 0.86 aw at 20 °C. There was no fungal growth for either A. flavus or A. parasiticus at 0.82 aw. The most rapid growth conditions for A. flavus and A. parasiticus were 0.94 aw at 35 °C, and 0.94 aw at 20 °C, respectively. Aspergillus flavus produced aflatoxins (13 μg/kg aflatoxin B1) only on seeds with 0.94 aw at 27 °C, while A. parasiticus produced high levels of aflatoxins under several conditions; the highest concentrations of aflatoxin B1 (175 μg/kg) and AFG1 (153 μg/kg) were produced on deoiled ground seeds with 0.94 aw at 27 °C. It is likely that storing ground deoiled nyjer seeds with a water activity up to 0.82 aw at 20 °C will reduce fungal growth aflatoxin production.

Nannocystis exedens: A Potential Biocompetitive Agent against Aspergillus flavus and Aspergillus parasiticus

2001 ◽  
Vol 64 (7) ◽  
pp. 1030-1034 ◽  
Author(s):  
WILLIE J. TAYLOR ◽  
FRANCES A. DRAUGHON
Keyword(s):  
Aspergillus Flavus ◽  
Yeast Extract ◽  
Biocontrol Agent ◽  
Aspergillus Parasiticus ◽  
Extract Agar ◽  
Potential Biocontrol Agent ◽  
Aflatoxigenic Fungi ◽  
Close Proximity ◽  
Zones Of Inhibition ◽  
Yeast Extract Agar

This study examined the potential for controlling toxigenic Aspergillus flavus and Aspergillus parasiticus by biological means using a myxobacterium commonly found in soil. The ability of Nannocystis exedens to antagonize A. flavus ATCC 16875, A. flavus ATCC 26946, and A. parasiticus NRRL 3145 was discovered. Cultures of aflatoxigenic fungi were grown on 0.3% Trypticase peptone yeast extract agar for 14 days at 28°C. When N. exedens was grown in close proximity with an aflatoxigenic mold, zones of inhibition (10 to 20 mm) developed between the bacterium and mold colony. A flattening of the mold colony on the sides nearest N. exedens and general stunting of growth of the mold colony were also observed. When N. exedens was added to the center of the cross-streak of a mold colony, lysis of the colony by the bacterium was observed after 24 h. Microscopic observations revealed that N. exedens grew on spores, germinating spores, hyphae, and sclerotia of the molds. These results indicate that N. exedens may be a potential biocontrol agent against A. flavus and A. parasiticus.

scholarly journals Does manufacturers' size affect the prevalence of mycobiota and occurrence of mycotoxins in spices and spice-based products?

2020 ◽  
Vol 13 (1) ◽  
pp. 83-95 ◽  
Author(s):  
A.I. Ahmad-Zaidi ◽  
M.A.A. Ghazali ◽  
N.A. Nik-Muhammad ◽  
N.S. Sazali ◽  
N. Mahror ◽  
...  
Keyword(s):  
Food Safety ◽  
Correlation Analysis ◽  
Ochratoxin A ◽  
Aspergillus Flavus ◽  
Large Scale ◽  
Aspergillus Parasiticus ◽  
Small Scale ◽  
Quality Level ◽  
Aflatoxin B ◽  
Food Safety And Quality

The present work aimed to establish the prevalence of mycobiota and occurrence of mycotoxins (aflatoxins and ochratoxin A) in spices and spice-based products, and correlate these to their manufacturers’ sizes. A total of 90 spice, sauce and paste samples were purchased; 3 manufacturer sizes (small, medium, large) × 3 types of samples (spices, sauces, pastes) × 5 brands × 2 replicates. The prevalence of mycobiota was assessed with dichloran rose bengal chloramphenicol (DRBC) and Aspergillus flavus and Aspergillus parasiticus (AFPA) medium, while the occurrence of mycotoxins was quantified with HPLC-FLD. Large-scale manufacturers were found to adopt a greater number of safety and quality certifications. Small-scale manufacturers significantly yielded the highest total fungal loads on DRBC (log 5.084±0.417 cfu/g paste, log 6.253±0.407 cfu/g sauce, log 6.662±0.222 cfu/g spice) and AFPA (log 4.461±0.451 cfu/g paste, log 5.661±0.395 cfu/g sauce, and log 6.269±0.432 cfu/g spice). Correlation analysis (Pearson’s r) revealed that manufacturers’ sizes positively influenced (DRBC r=0.781; AFPA r=0.702) the prevalence of mycobiota. Aflatoxin B1 was present in 6/30 (20%) paste samples, 1/30 sauce samples (3.33%) and 12/30 spice samples (40%). Aflatoxin B2 was only present in 2/30 sauce samples (6.67%). Aflatoxin G1 and G2 were absent from all samples. Ochratoxin A was present in 11/30 (36.67%) paste samples, 5/30 sauce samples (16.67%) and 21/30 spice samples (70%). It was found that, to a certain extent, the size of and certification adopted by manufacturers affected the prevalence of mycobiota and the occurrence of mycotoxins in spices and spice-based products analysed in the present work. Nevertheless, it is henceforth recommended that a surveillance study of this nature be extended and widened in terms of number of samples as well as type of spices, sauces and pastes to obtain a more thorough and significant profile of the products’ food safety and quality level.

scholarly journals Interactions between water activity and temperature on the Aspergillus flavus transcriptome and aflatoxin B 1 production

2017 ◽  
Vol 256 ◽  
pp. 36-44 ◽  
Author(s):  
Angel Medina ◽  
Matthew K. Gilbert ◽  
Brian M. Mack ◽  
Gregory R. OBrian ◽  
Alicia Rodríguez ◽  
...  
Keyword(s):  
Water Activity ◽  
Aspergillus Flavus ◽  
Aflatoxin B

Aspergillus nomius, an important aflatoxin producer in Brazil nuts?

2008 ◽  
Vol 1 (2) ◽  
pp. 123-126 ◽  
Author(s):  
M. Olsen ◽  
P. Johnsson ◽  
T. Möller ◽  
R. Paladino ◽  
M. Lindblad
Keyword(s):  
Aspergillus Flavus ◽  
Prevention And Control ◽  
Influence Strategies ◽  
Fungal Strains ◽  
Brazil Nuts ◽  
Aspergillus Nomius ◽  
Aflatoxin B ◽  
And Control ◽  
The Relationship

The relationship between aflatoxin B1 and G1 was examined in samples from 199 aflatoxin contaminated lots of inshell Brazil nuts imported to Europe. In most of the samples, the relationship between B1 and G1 were approximately 50/50 indicating that the major responsible aflatoxin producing fungi cannot be Aspergillus flavus, which produces solely B aflatoxins. Fungal strains were isolated from two batches of Brazil nuts and isolates of both A. nomius and A. flavus could be identified. The A. nomius isolates were good producers of both B and G aflatoxins, while the A. flavus strains only produced B aflatoxins. In conclusion, this study suggests that A. nomius is an important producer of aflatoxins in Brazil nuts and that its occurrence, and possibly other B and G aflatoxin producers, should be further examined since this may influence strategies for prevention and control of aflatoxins in Brazil nuts.

scholarly journals Potential of Aqueous Ozone to Control Aflatoxigenic Fungi in Brazil Nuts

2013 ◽  
Vol 2013 ◽  
pp. 1-6 ◽  
Author(s):  
Otniel Freitas-Silva ◽  
Héctor Morales-Valle ◽  
Armando Venâncio
Keyword(s):  
Aspergillus Flavus ◽  
Ozone Concentration ◽  
Optimal Treatment ◽  
Fungal Population ◽  
Alternative Technology ◽  
Brazil Nuts ◽  
Aflatoxigenic Fungi ◽  
Potential Use

This study aimed to verify the use of aqueous ozone as alternative technology for fungal control. Brazil nuts sterilized were inoculated with either 1×106 or 1×107 conidia mL−1 of Aspergillus flavus (MUM 9201) to determine optimal treatment parameters and different aqueous ozone contact times. These assays showed that the effect of ozone is almost immediate against A. flavus, and the optimum ozone concentration depended on the number of initial viable spores on the shell. The remaining viable spores in the ozone solution were recorded, and the rate of inactivation for each treatment was determined by assessing the ratio between the cfu of each treatment and the control. The ozonized nuts were also cultured to recover the fungal population. Aqueous ozone was effective in reducing the conidia of A. flavus and the natural fungal population associated with Brazil nuts. Aqueous ozone presented a great potential to reduce microorganisms counts in Brazil nuts with a great potential use in packing houses for decontamination step.

scholarly journals Fungi and Mycotoxins from Pre- and Poststorage Brewer's Grain Intended for Bovine Intensive Rearing

2012 ◽  
Vol 2012 ◽  
pp. 1-6 ◽  
Author(s):  
L. A. M. Keller ◽  
C. M. Pereyra ◽  
L. R. Cavaglieri ◽  
A. M. Dalcero ◽  
C. A. R. Rosa
Keyword(s):  
Ochratoxin A ◽  
Aspergillus Flavus ◽  
High Frequencies ◽  
Regular Monitoring ◽  
Colony Forming Units ◽  
Intensive Rearing ◽  
Natural Contamination ◽  
Contamination Levels ◽  
Aflatoxin B ◽  
Isolated Species

The aim of the study was to determine the mycobiota and natural levels of mycotoxins such as aflatoxin B1 (AFB1), ochratoxin A (OTA), fumonisin B1 (FB1), and deoxynivalenol (DON) present in brewers grains pre- and poststored intended for bovine intensive rearing. Poststored (80%) samples had counts higher than 1×104 colony-forming units (CFU/g). Cladosporium spp. and Aspergillus spp. were isolated at high frequencies. Aspergillus flavus was the prevalent isolated species. Prestored (70%) and poststored (100%) samples showed AFB1 levels over the recommended limits (20 μg/Kg), and OTA levels were below the recommended limits (50 μg/Kg) while pre- and poststored samples did not show FB1 and DON natural contamination levels. The presence of mycotoxins in this substrate indicates the existence of contamination. Regular monitoring of feeds is required in order to prevent chronic and acute toxic syndromes related to this kind of contamination.

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