Commercially available mycotoxin adsorbents often focus only on binding the ‘common’ mycotoxins, while data on the binding efficacy for the emerging mycotoxins remains limited. Many of the emerging mycotoxins are not yet standardized and are therefore difficult to include in analysis, even though it is important to know the effects of mycotoxin adsorbents against these toxins. Orffa continues to focus on fighting the threat of emerging mycotoxins, by performing trials to study the binding capacity of Orffa’s mycotoxin adsorbents Excential Toxin A and Excential Toxin Plus for the emerging mycotoxins alternariol, enniatin B, fusaric acid, beauvericin and sterigmatocystin.
The emerging mycotoxin threat; little information but high prevalence
Alternariol, one of the members of the emerging mycotoxins group, is produced by Alternaria fungi. Data on alternariol toxicity in animals is still limited and mostly originates from in vitro trials. It was suggested that this mycotoxin possesses genotoxic, cytotoxic and mutagenic properties. Alternariol has been shown to interact with the DNA and induce several DNA damage responses. Besides, it affects macrophages and reduces immune functioning. In 2021, alternariol was already shown to have a global prevalence of 35% in feed. This indicates the importance of more research into alternariol.
Another emerging mycotoxin is enniatin B, produced by Fusarium fungi. The main toxicity mechanism is hypothesized to be related to enniatin B’s ionophoric properties. Also, it depolarizes mitochondria and has negative effects on cellular metabolism. Mycotoxin analysis from 2021 shows that approximately 74% of the tested feed samples were contaminated with enniatin B.
Fusaric acid is a toxic metabolite of Fusarium fungi and also for this mycotoxin, relevant in vivo data on toxicity is scarce. It is expected that fusaric acid toxicity is related to oxidative stress, mitochondrial disfunction, and inhibition of cell proliferation, DNA synthesis and dopamine beta hydroxylase. Also for this mycotoxin, the prevalence in 2021 was shown to be already quite high with the occurrence of approximately 97%, 6% and 95% in corn, forage or grain samples respectively.
Beauveria bassiana and several Fusarium fungi are producers of beauvericin. Again, the toxicity mechanism is not yet fully understood but it is likely related to its functioning as a potassium-specific ionophore, inducing reactive oxygen species (ROS) and increasing oxidative stress which can result in apoptosis of cells. Also, beauvericin has been shown to activate various cellular signalling pathways, such as mitogen-activated protein kinase (MAPK), internal mitochondrial pathway, NF-κB, and p53, which can also result in apoptosis. However, besides some toxic effects, beauvericin has also been shown to have some antibacterial and antifungal properties. In 2021, the occurrence of beauvericin was already high, with a level of around 70% in the tested feed samples.
Sterigmatocystin is a metabolite of Aspergillus fungi. This emerging mycotoxin is considered to be closely related to aflatoxins and its toxic effects seem to resemble those of aflatoxin B1; carcinogenicity, mutagenicity and cytotoxicity. Information on toxicity is based on both in vitro and in vivo trials, which show toxic effects across species, with the liver and kidney being the most affected. The occurrence of this mycotoxin seems to be around 19%, based on analysis in 2021.