Resistance of maize landraces from Mexico to aflatoxin contamination: influence of aflatoxin-producing fungi genotype and length of incubation

2021 ◽  
Author(s):  
Alejandro Ortega-Beltran ◽  
Ramon Jaime ◽  
Peter J. Cotty
Keyword(s):  
Aflatoxin Contamination ◽  
Maize Landraces

Susceptibility to Aflatoxin Contamination among Maize Landraces from Mexico

2014 ◽  
Vol 77 (9) ◽  
pp. 1554-1562 ◽  
Author(s):  
ALEJANDRO ORTEGA-BELTRAN ◽  
MANUEL D. J. GUERRERO-HERRERA ◽  
ALEJANDRO ORTEGA-CORONA ◽  
VICTOR A. VIDAL-MARTINEZ ◽  
PETER J. COTTY
Keyword(s):  
Hybrid Control ◽  
Aflatoxin Contamination ◽  
Sources Of Resistance ◽  
Maize Cultivars ◽  
Resistance Variation ◽  
Maize Landraces ◽  
Aflatoxin Accumulation ◽  
Beneficial Traits ◽  
Fungal Reproduction ◽  
Maize Kernels

Maize, the critical staple food for billions of people, was domesticated in Mexico about 9,000 YBP. Today, a great array of maize landraces (MLRs) across rural Mexico is harbored in a living library that has been passed among generations since before the establishment of the modern state. MLRs have been selected over hundreds of generations by ethnic groups for adaptation to diverse environmental settings. The genetic diversity of MLRs in Mexico is an outstanding resource for development of maize cultivars with beneficial traits. Maize is frequently contaminated with aflatoxins by Aspergillus flavus, and resistance to accumulation of these potent carcinogens has been sought for over three decades. However, MLRs from Mexico have not been evaluated as potential sources of resistance. Variation in susceptibility to both A. flavus reproduction and aflatoxin contamination was evaluated on viable maize kernels in laboratory experiments that included 74 MLR accessions collected from 2006 to 2008 in the central west and northwest regions of Mexico. Resistant and susceptible MLR accessions were detected in both regions. The most resistant accessions accumulated over 99% less aflatoxin B1 than did the commercial hybrid control Pioneer P33B50. Accessions supporting lower aflatoxin accumulation also supported reduced A. flavus sporulation. Sporulation on the MLRs was positively correlated with aflatoxin accumulation (R = 0.5336, P < 0.0001), suggesting that resistance to fungal reproduction is associated with MLR aflatoxin resistance. Results of the current study indicate that MLRs from Mexico are potentially important sources of aflatoxin resistance that may contribute to the breeding of commercially acceptable and safe maize hybrids and/or open pollinated cultivars for human and animal consumption.

Production of Aflatoxin in Cocoa Beans

1979 ◽  
Vol 62 (5) ◽  
pp. 1076-1079 ◽  
Author(s):  
Lawrence M Lenovich ◽  
W Jeffrey Hurst
Keyword(s):  
High Pressure ◽  
Liquid Chromatography ◽  
Ivory Coast ◽  
Aspergillus Parasiticus ◽  
Aflatoxin Production ◽  
Growth Conditions ◽  
Aflatoxin Contamination ◽  
Cocoa Beans ◽  
Total Aflatoxin ◽  
Substrate Variation

Abstract Aflatoxin was produced in both non-autoclaved and autoclaved Ivory Coast cocoa beans inoculated with Aspergillus parasiticus NRRL 2999 under optimum laboratory growth conditions. Total aflatoxin levels ranged from 213 to 5597 ng/g substrate. Aflatoxin was quantitated by using high pressure liquid chromatography (HPLC). Raw, non-autoclaved cocoa beans, also inoculated with aspergilli, produced 6359 ng aflatoxin/g substrate. Variation in aflatoxin production between bean varieties was observed. Total aflatoxin levels of 10,446 and 23,076 ng/g substrate were obtained on Ivory Coast beans inoculated with A. parasiticus NRRL 2999 and NRRL 3240, respectively. Aflatoxin production on Trinidad and Malaysian beans was 28 and 65 ng aflatoxin/g substrate. These data support previously reported low level natural aflatoxin contamination in cocoa.

scholarly journals Detection of Aflatoxin in Poultry Feed and Feed Materials through Immuno Based Assay from Different Poultry Farms and Feed Factories in Bangladesh

2019 ◽  
Vol 35 (1) ◽  
pp. 75-78 ◽  
Author(s):  
Mahbuba Akter Lubna ◽  
Mita Debnath ◽  
Farzana Hossaini
Keyword(s):  
Health Risk ◽  
Positive Result ◽  
Mean Value ◽  
Aflatoxin Contamination ◽  
Control Measures ◽  
Poultry Feed ◽  
Enzyme Linked Immunosorbent Assay ◽  
Total Aflatoxin ◽  
Poultry Farms ◽  
Aflatoxin Concentration

Current study investigated the occurrence of aflatoxin contamination in poultry feed and feed materials in different poultry farms and feed factories in Bangladesh. A total of 100 samples of finished feed and raw feed materials were collected and tested through direct competitive Enzyme-Linked Immunosorbent Assay (ELISA) for total aflatoxin detection. Overall, 97% samples (n=97/100) in our study, were found positive for aflatoxin contamination. Among finished feed categories, layer grower feed contained highest level of aflatoxin with a mean value of 21.64 ppb whereas layer feed was less susceptible for aflatoxin contamination (mean value 9.49 ppb). Between raw feed materials, maize samples were highly contaminated (n=15/15, 100%) with aflatoxin while 86.67% soybean samples showed positive result. Twenty one percent (21%) of the samples in our study contained aflatoxin concentration more than the acceptable limit employed by USFDA and many other countries which might pose severe health risk to poultry and human consumer. Proper surveillance and immediate control measures should be taken to ensure safe poultry feed and feed materials. Bangladesh J Microbiol, Volume 35 Number 1 June 2018, pp 75-78

scholarly journals Aflatoxin contamination in food crops: causes, detection, and management: a review

2021 ◽  
Vol 3 (1) ◽  
Author(s):  
Abhishek Kumar ◽  
Hardik Pathak ◽  
Seema Bhadauria ◽  
Jebi Sudan
Keyword(s):  
High Temperature ◽  
Aspergillus Parasiticus ◽  
Fungal Species ◽  
Aflatoxin Contamination ◽  
Food Crops ◽  
Farming Practices ◽  
Resistant Varieties ◽  
Food Commodities ◽  
Post Harvesting ◽  
Favorable Conditions

AbstractMycotoxins are secondary metabolites produced by several fungal species and molds. Under favorable conditions like high temperature and moisture, they contaminate a large number of food commodities and regional crops during pre and post-harvesting. Aflatoxin is the main mycotoxin that harm animal and human health due to its carcinogenic nature. Aflatoxins are mainly released by Aspergillus flavus and Aspergillus parasiticus. AFB1 constitutes the most harmful type of aflatoxins and is a potent hepato-carcinogenic, mutagenic, teratogenic and it suppresses the immune system. To maintain food safety and to prevent aflatoxin contamination in food crops, combined approaches of using resistant varieties along with recommended farming practices should be followed. This review concentrates on various aspects of mycotoxin contamination in crops and recent methods to prevent or minimize the contamination.

A Phytoalexin and Aflatoxin Producing Peanut Seed Culture System

1994 ◽  
Vol 21 (2) ◽  
pp. 130-134 ◽  
Author(s):  
S. M. Basha ◽  
R. J. Cole ◽  
S. K. Pancholy
Keyword(s):  
Water Stress ◽  
Culture System ◽  
Fungal Growth ◽  
Aflatoxin Contamination ◽  
Peanut Seed ◽  
Seed Culture ◽  
Murashige And Skoog Medium ◽  
Yellow Orange ◽  
Increased Susceptibility

Abstract An in vitro seed culture system was established to grow peanut seed of different maturities viz. white, yellow, orange, brown and black, using a modified Murashige and Skoog medium. Under this system peanut seed of yellow, orange, brown and black maturity categories grew to maturity as measured by increase in their size and germinability. In vitro cultured seeds produced significant amounts of phytoalexins and were contaminated with aflatoxins following their inoculation with Aspergillus spp. while the noninoculated sterile controls did not produce any phytoalexins. Exposure of seed cultures to water stress using various concentrations of mannitol (0 to 1 M) and polyethylene glycol 8000 (0-30% w/v) caused a significant decrease in their phytoalexin producing ability, and enhanced fungal growth compared to the nonstressed controls. The seeds that were stressed with mannitol and subsequently inoculated with A. flavus and A. parasiticus showed a significant increase in the aflatoxin contamination of stressed seed compared to the unstressed control. This would indicate that in vitro grown seeds responded to water stress similar to the field grown peanuts by loosing their ability to produce phytoalexins and increased susceptibility to aflatoxin contamination. Hence, this system has a potential application in evaluating peanut genotypes for aflatoxin resistance under water stress.

scholarly journals Determining future aflatoxin contamination risk scenarios for corn in Southern Georgia, USA using spatio-temporal modelling and future climate simulations

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Ruth Kerry ◽  
Ben Ingram ◽  
Esther Garcia-Cela ◽  
Naresh Magan ◽  
Brenda V. Ortiz ◽  
...  
Keyword(s):  
Strong Association ◽  
Growth Period ◽  
Aflatoxin Contamination ◽  
Adaptation Strategies ◽  
Future Climate ◽  
Climate Data ◽  
Emissions Scenarios ◽  
Rcp 8.5 ◽  
Maximum Temperatures ◽  
Southern Georgia

AbstractAflatoxins (AFs) are produced by fungi in crops and can cause liver cancer. Permitted levels are legislated and batches of grain are rejected based on average concentrations. Corn grown in Southern Georgia (GA), USA, which experiences drought during the mid-silk growth period in June, is particularly susceptible to infection by Aspergillus section Flavi species which produce AFs. Previous studies showed strong association between AFs and June weather. Risk factors were developed: June maximum temperatures > 33 °C and June rainfall < 50 mm, the 30-year normals for the region. Future climate data were estimated for each year (2000–2100) and county in southern GA using the RCP 4.5 and RCP 8.5 emissions scenarios. The number of counties with June maximum temperatures > 33 °C and rainfall < 50 mm increased and then plateaued for both emissions scenarios. The percentage of years thresholds were exceeded was greater for RCP 8.5 than RCP 4.5. The spatial distribution of high-risk counties changed over time. Results suggest corn growth distribution should be changed or adaptation strategies employed like planting resistant varieties, irrigating and planting earlier. There were significantly more counties exceeding thresholds in 2010–2040 compared to 2000–2030 suggesting that adaptation strategies should be employed as soon as possible.

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