Abstract
Aflatoxin B1, a type of highly toxic mycotoxin produced by some species belonging to the Aspergillus genus, such as Aspergillus flavus and Aspergillus parasiticus, is widely distributed in feed matrices. Here, coumarin was used as the sole carbon source to screen microorganism strains that were isolated from types of feed ingredients. Only one isolate (ND-1) was able to degrade aflatoxin B1 after screening. ND-1 isolate, identified as a strain of Aspergillus niger using phylogenetic analysis on the basis of 18S rDNA, could remove 26.3% of aflatoxin B1 after 48 h of fermentation in nutrient broth (NB). Optimization of fermentation conditions for aflatoxin B1 degradation by selected Aspergillus niger was also performed. These results showed that 58.2% of aflatoxin B1 was degraded after 24 h of culture under the optimal fermentation conditions. The aflatoxin B1 degradation activity of Aspergillus niger supernatant was significantly stronger than cells and cell extracts. Furthermore, effects of temperature, heat treatment, pH, and metal ions on aflatoxin B1 degradation by the supernatant were examined. Results indicated that aflatoxin B1 degradation of Aspergillus niger is enzymatic and this process occurs in the extracellular environment.
Highlights
With the growing frequency of food and feed safety issues, there has been an increased focus, on bio-pollution problems, in which fungal toxins are one of the main factors causing food and feed contamination
Isolate ND-1 and ND-2 were inoculated onto aflatoxin B1-containing nutrient agar (NA) to estimate its ability to remove aflatoxin B1
We employed a method using coumarin as a selective agent to search for aflatoxin B1 degradation microorganisms in this study
Summary
With the growing frequency of food and feed safety issues, there has been an increased focus, on bio-pollution problems, in which fungal toxins are one of the main factors causing food and feed contamination. Similar to many microbial secondary metabolites, aflatoxins consist of a family of closely related compounds, which include aflatoxin B1, B2, G1, G2, M1, and M2. On the basis of the severe hypertoxicity and wide distribution demonstrated by aflatoxin B1, many physical and chemical methods have been applied to inactivate and detoxify this compound in feed systems [8,9]. Most physical and chemical detoxification methods have their own limitations, such as a loss of the product organoleptic qualities and feed nutritional value, unknown health effects, and the high cost of specific equipment [10]. It has been reported that bacteria and fungi can contribute to the reduction of aflatoxins via biological degradation [11,12]. Farzaneh et al [14] found that Bacillus subtilis
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
