What are mycotoxins in food and feed? 

Christina Marantelou

Agriculturalist - Food Scientist, M.Sc. Nanobiotechnology

9 min read
What are mycotoxins in food and feed? 

What are the implications for animal productivity, feed security and human health? 

How can nanotechnology be used to prevent and eliminate mycotoxin contamination in the food and feed supply chain? 

Mycotoxins are a major global concern and a significant challenge for food safety due to their harmful effects. Their prevalence in food crops has been suggested to be in the range of 60–80% and over USD 932 million annual financial losses in agricultural commodities contaminated with mycotoxins reported globally (1),(2). These low molecular weight toxic metabolites originate from mycotoxigenic fungi such as Aspergillus, Alternaria, Fusarium and Penicillium spp.; and contaminate various categories of foods and feeds (3),(4). Over 400 mycotoxins have been classified as toxic, and the harmful effects of mycotoxicosis caused by mycotoxin contamination in humans have been documented, including necrosis, hepatitis, haemorrhage, gynecomastia with testicular atrophy, neurological disorders, cancer and death in extreme cases (1),(5),(6). Likewise, animal feedstuff contaminated with mycotoxins can lead to reductions in available feed nutrients, chronic diseases, damage to animal health, eventual death and reduced production (7). The most toxic types of mycotoxins are aflatoxins (AF) and ochratoxins (OT) (8). AFB1 is a strong hepatocarcinogenic mycotoxin mostly detected in cereals, nuts, grains and feeds, and AFB1 and AFB2 can be converted to hydroxylated AFM1 and AFM2 in lactating cattle after ingestion via contaminated feedstuff. In contrast, OTA with hepatotoxic and nephrotoxic effects is mostly detected in cereals, coffee, wine, grape juice and dried fruits (9),(10). Therefore, there is an urgent need for appropriate approaches and techniques for reducing and/or eliminating the presence of mycotoxins in foods. The chemical structures of the main mycotoxins in foods are presented in Fig. 1, while the classes of mycotoxins based on symptoms and diseases caused to animals and humans are presented in Table 1.

Figure 1. Chemical structures of the main mycotoxins in foods (11).

Table 1. Classes of mycotoxins based on symptoms and diseases caused to animals and humans (11).

What are mycotoxins in food and feed? 

 

The risk of food contamination by mycotoxins can be increased from the environmental, agronomic and socioeconomic points of view and be found in all segments of the animal feed supply chain (Figure 2). 

What are mycotoxins in food and feed? 

Figure 2. Factors affecting mycotoxin occurrence in the human food and animal feed chains. (adapted from Pestka and Casale, 1990) (12)

Factors influencing mycotoxin production and contamination in foods

Mycotoxins can grow on a wide range of agricultural and food products. The most common source of exposure to humans are contaminated cereals, cereal-based products and food produced by animals exposed to mycotoxins. Contamination can occur from pre-harvest to postharvest stages along the food management chain and the presence of fungi does not necessarily translate to mycotoxin contamination, as mycotoxins production conditions are specific and independent of fungal growth conditions. The food safety management system (FSMS) is a preparedness, monitoring, and prevention system for managing food hygiene and safety in food-related businesses. It has been suggested as a potential approach for influencing or preventing mycotoxin production in agricultural products and foods. T The FSMS was seen as a practical tool for controlling the food production process and environment to ensure the safety of the final products for consumption and typically includes procedures and management policies based on good hygiene practices (GHP), good agricultural practices (GAP), good storage practices (GSP), good manufacturing practices (GMP) and hazard analysis and critical control point (HACCP).

Food safety control can be achieved by monitoring at all stages and the implementation of proper processing conditions for reducing mycotoxigenic fungi and by extension controlling the presence of mycotoxins in food products. Implementation of the prerequisite programs like the HACCP-based procedures can reduce mycotoxin contamination, while conventional chemical, biological and physical methods can be employed for detoxification after contamination. A comprehensive manual on the application of the HACCP system for controlling and preventing mycotoxin production identifies stages for monitoring systems and steps in processing where mycotoxins can be prevented or eradicated (13),(14). Due to growing resistance to conventional methods and their difficulties, there is a need to develop new and innovative strategies that can rapidly eliminate mycotoxins with minimal impact on quality and within a short processing time.  (11). The conventional methods i.e., physical, chemical and biological strategies for detoxifying mycotoxins in foods, are shown in Fig. 3. 

Fig. 3. Conventional methods: (A) physical, (B) chemical, and (C) biological for detoxifying mycotoxins in foods (11).

Mycotoxin occurrence and contamination along the agricultural produce, food and animal feedstuff management chain are of global concern owing to their toxicity,the danger they pose to both human and animal health, and the associated economic losses. Even with the implementation of the prerequisite programs of the food management systems like GAP, GMP, GSP, GHP and HACCP-based procedures at the appropriate stages of pre-harvest, postharvest and processing, mycotoxin contamination is unavoidable (14). Early and swift detection is therefore vital for elimination, the overall safety of foods, and preventing related health problems. Increasing consumer awareness of food safety, regulatory issues, the potential formation of carcinogenic by-products, limited efficiency and possible alterations in quality have limited the applications of conventional chemical, biological and physical detoxifying methods. Besides, increasing resistance, especially by new strains to the conventional methods has geared research towards innovative strategies for the rapid control, reduction and elimination of mycotoxins in foods with short processing time and negligible impact on morphological, physicochemical, textural and structural properties of food and the environment as well.

Magnetic materials and nanoparticles present great potential in various aspects of the food, agriculture and livestock industries. Their adsorbent capability on mycotoxins is a great addition. However, like the phytochemical inhibitors, the application is still in infancy. Studies have recently emerged to support the eco-friendly, low-cost and effective means of controlling mycotoxins through the use of magnetic materials and nanoparticles. For example, magnetic particles ( Fe₃O₄) that were coated with chitosan were shown to be effective for the adsorption of patulin from fruit juice. The conjugation of nanocellulose with retinoic acid could adsorb AFB1 from a variety of food items without any trace of toxicity, depending on the concentration and pH (15), (16). Magnetic nanoparticles like nano-clay, nano-gel, surface-active maghemite, nanomaterials like zinc oxide nanoparticles (ZON), silver nanoparticles (SLN), copper nanoparticles and selenium nanoparticles (SEN) were effective for removing and binding mycotoxins in agricultural feedstuff and foods (17), (18). Scientists  (19) reviewed the key properties of carbon nanoparticles such as fullerenes, carbon nanotubes and graphene (native graphene (G), graphene oxide (GO) and reduced graphene (rGO)) and the possible binding interaction with mycotoxins (Fig. 4). Mycotoxins can be bound to the surface, bundles, grooves, or channels between these nanoparticles through different binding interaction, but so far, the interaction of NPs with the individual components of the fungi cells is still lacking and yet to be investigated.

Figure 4. Binding interactions of carbon nanoparticles with mycotoxins, i.e., (A) fullerenes, (B) carbon nanotubes and (C) grapheme.

Mycotoxins pose a significant risk to the health and well-being of humans and animals and are a significant food safety issue. Despite the research effort that has attempted to delineate the multiple aspects of mycotoxin contamination of the human food and animal feed supply chains, many questions still need to be answered. Although mycotoxicoses have been known for centuries, it is only in the last 50 years that we have achieved an understanding of the production, chemistry and biological effects of these natural feed contaminants (20). In that time, strategies have been developed, including agronomic practices, plant breeding and transgenics, biotechnology, toxin binding and deactivating feed additives, and education of feed suppliers and animal producers to reduce mycotoxin contamination and exposure (21). Nevertheless, it has proven difficult to control the exposure of man and animals to these natural environmental compounds. This is a significant global issue of food and feed security and we will have to live with some degree of risk. The situation is further complicated when it is appreciated that there are many thousand secondary fungal metabolites (22), the vast majority of which have not been tested for toxicity or associated with disease outbreaks or reduced animal productivity. However, with increased awareness and ongoing surveillance for mycotoxins, the feed industry and animal producers will produce better and safer products.

References:

  1. Adebo, O. A., Molelekoa, T., Makhuvele, R., Adebiyi, J. A., Oyedeji, A. B., Gbashi, S., et al. (2021). A review on novel non-thermal food processing techniques formycotoxin reduction. International Journal of Food Science and Technology, 56 (1), 13–27. https://doi.org/10.1111/ijfs.147344
  2. Moretti, A., Pascale, M., & Logrieco, A. F. (2019). Mycotoxin risks under a climate change scenario in Europe. Trends in Food Science & Technology, 84, 38–40. https://doi.org/10.1016/j.tifs.2018.03.008
  3. Emmanuel, K. T., Els, V. P., Bart, H., Evelyne, D., Els, V. H., & Els, D. (2020). Carry-over of some Fusarium mycotoxins in tissues and eggs of chickens fed experimentally mycotoxin-contaminated diets. Food and Chemical Toxicology, 145, Article 111715. https://doi.org/10.1016/j.fct.2020.111715
  4. Gavahian, M., Sheu, S. C., Magnani, M., & Mousavi Khaneghah, A. (2021). Emerging technologies for mycotoxins removal from foods: Recent advances, roles in sustainable food consumption, and strategies for industrial applications. Journal of Food Processing and Preservation. , Article e15922. https://doi.org/10.1111/jfpp.15922
  5. Atanda, S. A. (2011). Fungi and mycotoxins in stored foods. African Journal of Microbiology Research, 5(25), 4373–4382. https://doi.org/10.5897/ajmr11.487
  6. Milicevic, D., Nesic, K., & Jaksic, S. (2015). Mycotoxin contamination of the food supply chain - implications for one health programme. Procedia Food Science, 5, 187–190. https://doi.org/10.1016/j.profoo.2015.09.053
  7. Luo, Y., Liu, X., & Li, J. (2018). Updating techniques on controlling mycotoxins – a review. Food Control, 89, 123–132. https://doi.org/10.1016/j.foodcont.2018.01.016
  8. Hamad, G. M., El-Makarem, H. A., Elaziz, A. A., Amer, A. A., El-Nogoumy, B. A., & Abou-Alella, S. A. (2022). Adsorption efficiency of sodium & calcium bentonite for ochratoxin A in some Egyptian cheeses: An innovative fortification model, in vitro and in vivo experiments. World Mycotoxin Journal, 15(3), 285–300. https://doi.org/10.3920/WMJ2021.2682
  9. Bangar, S. P., Sharma, N., Kumar, M., Ozogul, F., Purewal, S. S., & Trif, M. (2021). Recent developments in applications of lactic acid bacteria against mycotoxin production and fungal contamination. Food Bioscience, 44, Article 101444. https://doi.org/10.1016/j.fbio.2021.101444
  10. Smith, M. C., Madec, S., Coton, E., & Hymery, N. (2016). Natural Co-occurrence of mycotoxins in foods and feeds and their in vitro combined toxicological effects. Toxins, 8(4), 94. https://doi.org/10.3390/toxins8040094
  11. Hamad G. M., A., Mehany T., Gandara, J.-S., Abou-Alella S., Esua, O. J., Abdel-Wahhab M.A., Hafez E.E. (2023) A review of recent innovative strategies for controlling mycotoxins in foods. Food Control  144, Article 109350.
  12. Pestka, J.J., Casale, W.L., 1990. Naturally occurring fungal toxins. Adv Environ. Sci. Technol. 23, 613–638.
  13. FAO. (2001). Manual on the application of the HACCP system in mycotoxin prevention and control. FAO Food and Nutrition Paper 73. Joint FAO/WHO Food Standards Programme FAO http://books.google.com/books?hl=en&lr=&id=kUjDSC5NVkUC&oi=fnd&pg=PR3&dq=Manual+on+the+application+of+the+HACCP+ystem+in+Mycotoxin+prevention+and+control&ots=wmRA7j479c&sig=COKalIkuJ5JCSBQTe-aXXQNfTFk
  14. Nada, S., Nikola, T., Bozidar, U., Ilija, D., & Andreja, R. (2022). Prevention and practical strategies to control mycotoxins in the wheat and maize chain. Food Control, 136, Article 108855. https://doi.org/10.1016/j.foodcont.2022.108855
  15. Jebali, A., Yasini Ardakani, S. A., Sedighi, N., & Hekmatimoghaddam, S. (2015). Nanocellulose conjugated with retinoic acid: Its capability to adsorb aflatoxin B1. Cellulose, 22(1), 363–372. https://doi.org/10.1007/s10570-014-0475-0
  16. Luo, Y., Zhou, Z., & Yue, T. (2017). Synthesis and characterization of nontoxic chitosancoated Fe3O4 particles for patulin adsorption in a juice-pH simulation aqueous. Food Chemistry, 221, 317–323. https://doi.org/10.1016/j.foodchem.2016.09.008
  17. Abd-Elsalam, K. A., Hashim, A. F., Alghuthaymi, M. A., & Said-Galiev, E. (2017). Nanobiotechnological strategies for toxigenic fungi and mycotoxin control. In A. M. Grumezescu (Ed.), Food preservation (pp. 337–364). Elsevier Academic Press. https://doi.org/10.1016/b978-0-12-804303-5.00010-9
  18. Magro, M., Moritz, D. E., Bonaiuto, E., Baratella, D., Terzo, M., Jakubec, P., et al. (2016). Citrinin mycotoxin recognition and removal by naked magnetic nanoparticles. Food Chemistry, 203, 505–512. https://doi.org/10.1016/j.foodchem.2016.01.147
  19. Horky, P., Skalickova, S., Baholet, D., & Skladanka, J. (2018). Nanoparticles as a solution for eliminating the risk of mycotoxins. Nanomaterials, 8(9), 727. https://doi.org/10.3390/nano8090727
  20. Richard, J.L., 2007. Some major mycotoxins and their mycotoxicoses; An overview. Int. J. Food Microbiol. 119, 3–10.
  21. Bryden, W.L., 2009. Mycotoxins and mycotoxicoses: significance, occurrence and mitigation in the food chain. In: Ballantyne, B., Marrs, T., Syversen, T. (Eds.), General and Applied Toxicology. , third ed. John Wiley & Sons Ltd, Chichester, UK, pp. 3529–3553.
  22. Cole, R.J., Scheweikert, M.A., Jarvis, B.B., 2003. Handbook of Secondary Fungal Metabolites, Vols. I–III. Academic Press, CA, USA.