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.

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.

scholarly journals Streptomyces roseolus, A Promising Biocontrol Agent Against Aspergillus flavus, the Main Aflatoxin B1 Producer

Toxins ◽  
2018 ◽  
Vol 10 (11) ◽  
pp. 442 ◽  
Author(s):  
Isaura Caceres ◽  
Selma Snini ◽  
Olivier Puel ◽  
Florence Mathieu
Keyword(s):  
Aspergillus Flavus ◽  
Aflatoxin B1 ◽  
Biocontrol Agent ◽  
Cyclopiazonic Acid ◽  
Over Expression ◽  
Expression Of Genes ◽  
B1 Gene ◽  
Genes Encoding ◽  
Molecular Mechanism Of Action ◽  
Potential Use

Crop contamination by aflatoxin B1 is a current problem in tropical and subtropical regions. In the future, this contamination risk may be expanded to European countries due to climate change. The development of alternative strategies to prevent mycotoxin contamination that further contribute to the substitution of phytopharmaceutical products are thus needed. For this, a promising method resides in the use of biocontrol agents. Several actinobacteria strains have demonstrated to effectively reduce the aflatoxin B1 concentration. Nevertheless, the molecular mechanism of action by which these biological agents reduce the mycotoxin concentration has not been determined. The aim of the present study was to test the potential use of Streptomyces roseolus as a biocontrol agent against aflatoxin B1 contamination. Co-cultures with Aspergillus flavus were conducted, and the molecular fungal response was investigated through analyzing the q-PCR expression of 65 genes encoding relevant fungal functions. Moreover, kojic and cyclopiazonic acid concentrations, as well as morphological fungal changes were also analyzed. The results demonstrated that reduced concentrations of aflatoxin B1 and kojic acid were respectively correlated with the down-regulation of the aflatoxin B1 gene cluster and kojR gene expression. Moreover, a fungal hypersporulated phenotype and a general over-expression of genes involved in fungal development were observed in the co-culture condition.

Soil-Borne Pests of Peanut in Growers' Fields with Different Cropping Histories in Alabama1

1996 ◽  
Vol 23 (1) ◽  
pp. 36-42 ◽  
Author(s):  
K. L. Bowen ◽  
A. K. Hagan ◽  
J. R. Weeks
Keyword(s):  
Aspergillus Flavus ◽  
Meloidogyne Incognita ◽  
Leaf Spot ◽  
Sclerotium Rolfsii ◽  
Stem Rot ◽  
Peanut Seed ◽  
Control Programs ◽  
Aflatoxigenic Fungi ◽  
Peanut Production ◽  
Seed Invasion

Abstract Pest levels and yields of peanut were monitored in growers' fields in 1991 through 1993. Yields ranged from 2085 to 6440 kg/ha and averaged 3947 kg/ha over the 3 yr. Incidence of southern stem rot (SSR) (caused by Sclerotium rolfsii) averaged 7.6 foci (up to 30 cm in length) per 30.5 m row and ranged from 0 to 31.0 foci. Peanut yield tended to be inversely related to incidence of SSR and directly related to the number of years between peanut crops. Incidence of SSR was inversely related to number of years between peanut crops and was consistently greater in fields cropped to peanut every other year compared to other fields with less intensive peanut production. Yields obtained from irrigated fields averaged 11.4% greater than those without irrigation. Leaf spot control programs used by growers provided consistent levels of control. Peanut seed invasion by aflatoxigenic fungi and plant damage by larvae of the lesser cornstalk borer (Elasmopalus lignosellus) generally were low. Seed invasion by Aspergillus flavus-type fungi was positively correlated (P < 0.05) with damage due to lesser cornstalk borer in 1993. Juvenile populations of root knot nematodes (Meloidogyne incognita) were positively correlated (P < 0.001) with incidence of SSR in 1992.

scholarly journals Effect of kebar grass (Biophytum petersianum Klotzsch) leaf extract on the growth and morphological structure of aflatoxigenic Aspergillus flavus

Food Research ◽  
2019 ◽  
Vol 4 (1) ◽  
pp. 234-243
Author(s):  
M.M. Lisangan ◽  
R. Syarief ◽  
W.P. Rahayu ◽  
O.S. Dharmaputra
Keyword(s):  
Aspergillus Flavus ◽  
Mycelial Growth ◽  
Morphological Structure ◽  
Fungal Growth ◽  
Morphological Alterations ◽  
Extract Concentration ◽  
Growth Inhibitory ◽  
Aflatoxigenic Fungi ◽  
Biophytum Petersianum ◽  
Observation Results

The objective of this study was to investigate the antifungal activity of kebar grass (Biophytum petersianum Klotzsch) extract (KGE) on the mycelial growth, conidiation and morphological structure of two types of aflatoxigenic fungus, which are Aspergillus flavus BCCF 0219 and A. flavus BIO 2236. They were isolated in the three types of model media, namely carbohydrate-enriched medium, fat-enriched medium and protein-enriched medium with five concentrations of KGE (12, 14, 16, 18, and 20 mg/mL) on each media. The best extract concentration of that inhibits the growth of A. flavus BCCF 0219 was found in the carbohydrate-enriched medium (95.7%), which was 12 mg/mL, whereas at A. flavus BIO 2236 was found in the fat-enriched medium (100%), which was 16 mg/mL. Based on SEM observation results, it was found that the mechanisms involved in fungal growth inhibitory by the KGE were by morphological alterations of the hyphal development, and the collapse of the entire hyphae. These findings indicated that KGE as a potential natural antifungal agent, particularly against aflatoxigenic fungi.

Ozonation of Brazil Nuts in Aqueous Media at Different pH Levels: Ozone Decomposition, Aspergillus flavus Inactivation, and Effects on Nut Color and Crude Oil Lipid Profile

2020 ◽  
pp. 1-12
Author(s):  
Wallas Felippe de Souza Ferreira ◽  
Ernandes Rodrigues de Alencar ◽  
Luiz Eduardo Bassay Blum ◽  
Márcia de Aguiar Ferreira ◽  
Marcio Antônio Mendonça ◽  
...  
Keyword(s):  
Crude Oil ◽  
Lipid Profile ◽  
Aspergillus Flavus ◽  
Aqueous Media ◽  
Ozone Decomposition ◽  
Brazil Nuts

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.

The control of Aspergillus flavus with Cinnamomum jensenianum Hand.-Mazz essential oil and its potential use as a food preservative

2012 ◽  
Vol 130 (3) ◽  
pp. 520-527 ◽  
Author(s):  
Jun Tian ◽  
Bo Huang ◽  
Xiuli Luo ◽  
Hong Zeng ◽  
Xiaoquan Ban ◽  
...  
Keyword(s):  
Essential Oil ◽  
Aspergillus Flavus ◽  
Food Preservative ◽  
Potential Use

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.

scholarly journals Antifungal Activity of Metabolites from the Marine Sponges Amphimedon sp. and Monanchora arbuscula against Aspergillus flavus Strains Isolated from Peanuts (Arachis hypogaea)

2014 ◽  
Vol 9 (1) ◽  
pp. 1934578X1400900 ◽  
Author(s):  
Cynthia Arevabini ◽  
Yasmin D. Crivelenti ◽  
Mariana H. de Abreu ◽  
Tamires A. Bitencourt ◽  
Mário F. C. Santos ◽  
...  
Keyword(s):  
Antifungal Activity ◽  
Arachis Hypogaea ◽  
Aspergillus Flavus ◽  
Biosynthetic Pathway ◽  
Its Region ◽  
Marine Sponges ◽  
Marine Alkaloids ◽  
Lead Compounds ◽  
Arachis Hypogaea L ◽  
Aflatoxigenic Fungi

Contamination of preharvest and stored peanuts ( Arachis hypogaea L.) by aflatoxigenic strains of Aspergillus flavus is an important economical and food safety problem in many tropical and subtropical areas of the world. The present investigation reports the antifungal activity of a halitoxins/amphitoxins enriched extract obtained from the sponge Amphimedon sp. (HAEEAsp), and of batzelladine L isolated from the sponge Monanchora arbuscula on Aspergillus flavus isolated from stored peanuts. A PCR system directed against the ITS region and aflatoxin biosynthetic pathway genes of A. flavus was applied for identification of aflatoxin producing strains. The HAEEAsp extract and batzelladine L showed minimal inhibitory concentration (MIC) in the range between 1.9 to 15.6 μg/mL and between 1.9 to 7.8 μg/mL, respectively. The minimal fungicide concentration (MFC) of HAEEAsp extract and batzelladine L was in the range between 3.9 to 31.3 μg/mL and 3.9 to 15.6 μg/mL, respectively. These results indicate that these marine alkaloids may be further explored for the development of potential lead compounds active against aflatoxigenic fungi.

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