Related Experiment Videos
Production of sterigmatocystin by Aspergillus versicolor isolated from roughage
1Academy of Agricultural Sciences of the German Democratic Republic, Institute of Forage Production Paulinenaue.
Abstract:
A total of 69 samples of hay and straw collected during the winter period of 1984/85 were surveyed for their contamination by Aspergillus versicolor. The percentage of A. versicolor-positive samples was 14.5%. Nineteen A. versicolor strains mainly isolated from roughage were tested for the production of sterigmatocystin. All of the isolates examined were capable of producing different levels of sterigmatocystin on a cracked corn substrate. The majority of these strains were highly toxigenic; 53% of the isolates produced more than 500 mg/kg of sterigmatocystin. These findings suggest that corn is a very suitable substrate for sterigmatocystin production and that particularly in the surface layers of feed stocks and corn silos such toxigenic strains of A. versicolor can produce considerable growth and possibly sterigmatocystin, too.
Insights
Aspergillus versicolor contamination was found in 14.5% of hay and straw samples. Most isolated strains produced high levels of sterigmatocystin on corn, indicating a risk in feed storage.
Area of Science:
- Mycology
- Food Safety
- Toxicology
Background:
- Aspergillus versicolor is a common fungus found in agricultural environments.
- Contamination of feedstuffs with toxigenic fungi poses a risk to animal health.
- Sterigmatocystin is a mycotoxin produced by Aspergillus species with potential health implications.
Purpose of the Study:
- To assess the prevalence of Aspergillus versicolor in hay and straw samples.
- To evaluate the sterigmatocystin-producing capability of Aspergillus versicolor strains isolated from roughage.
- To determine the suitability of corn as a substrate for sterigmatocystin production by Aspergillus versicolor.
Main Methods:
- Survey of 69 hay and straw samples for Aspergillus versicolor.
- Isolation and identification of Aspergillus versicolor strains.
- Testing of 19 Aspergillus versicolor isolates for sterigmatocystin production on a cracked corn substrate.
Main Results:
- 14.5% of the surveyed samples were positive for Aspergillus versicolor.
- All 19 tested Aspergillus versicolor strains produced sterigmatocystin on cracked corn.
- 53% of the isolates were highly toxigenic, producing over 500 mg/kg of sterigmatocystin.
Conclusions:
- Aspergillus versicolor is prevalent in hay and straw, posing a contamination risk.
- Corn is a highly suitable substrate for sterigmatocystin production by toxigenic Aspergillus versicolor strains.
- Toxigenic Aspergillus versicolor strains can proliferate and produce sterigmatocystin in feed stocks, especially on corn surfaces.