What is the Difference Between Mycotoxins and Aflatoxins

The main difference between mycotoxins and aflatoxins is that mycotoxins are toxic substances produced by fungi whereas aflatoxins are a type of mycotoxin, genotoxic, and cause DNA damage and cause cancer.

So, briefly, both mycotoxins and aflatoxins are two types of toxins in fungi. Moreover, they are secondary metabolites of fungi. And importantly, they cause diseases in humans and animals.

Key Areas Covered

1. What are Mycotoxins
   • Definition, Characteristics, Importance
2. What are Aflatoxins
   • Definition, Characteristics, Importance
3. Similarities Between Mycotoxins and Aflatoxins
   • Outline of Common Features
4. Difference Between Mycotoxins and Aflatoxins
   • Comparison of Key Differences

Key Terms

Aflatoxins, Mycotoxins

What are Mycotoxins

Mycotoxins are secondary metabolites of the kingdom of Fungi. They are toxic to humans and animals and can cause diseases and death. Aflatoxin, citrinin, fumonisins, ochratoxin A, patulin, trichothecenes, zearalenone, and ergot alkaloids such as ergotamine are examples of such disease-causing mycotoxins. Furthermore, one mold species may produce many different mycotoxins, and several species may produce the same mycotoxin.

Figure 1: Aspergillus parasiticus

Most fungi are aerobic and therefore, they use oxygen as the final electron acceptor during cellular respiration. They occur almost everywhere in extremely small quantities due to the minute size of their spores. Also, under normal conditions such as humidity and temperature, they consume organic matter for their cellular respiration. Moreover, they proliferate under the right conditions and form colonies, increasing the production of mycotoxins. However, mycotoxins are secondary metabolites and they are not necessary for the growth of the fungi. But, mycotoxins weaken the receiving host. In addition, the production of toxins depends on the surrounding intrinsic and extrinsic environments, and these substances vary greatly in their toxicity, depending on the organism infected and its susceptibility, metabolism, and defense mechanisms.

What are Aflatoxins

Aflatoxins are a type of mycotoxin produced by Aspergillus species of fungi, such as A. flavus and A. parasiticus. Aspergillus is a fungus that grows in soil, decaying vegetation, and various staple foodstuffs and commodities such as hay, sweetcorn, wheat, millet, sorghum, cassava, rice, chili peppers, cottonseed, peanuts, tree nuts, sesame seeds, sunflower seeds, and various spices. In short, this fungus can grow on almost any crop or food. When contaminated food is consumed, the aflatoxins enter the body through the gastrointestinal tract. Moreover, the animals that eat this contaminated food can pass aflatoxin transformation products into eggs, milk products, and meat.

Figure 2: Alfatoxin B1

Aflatoxins are very poisonous, and carcinogenic, and they are mutagens that cause DNA damage. In addition, there are four types of aflatoxins: aflatoxin B1, B2, G1, and G2. Here, the most toxic aflatoxin is the aflatoxin B1. Usually, it is a carcinogen and can generate adverse effects such as liver cancer.

Similarities Between Mycotoxins and Aflatoxins

• Mycotoxins and aflatoxins are two types of toxic substances produced by fungi.
• They are secondary metabolites of fungi.
• They can cause diseases and death in humans and other animals.

Difference Between Mycotoxins and Aflatoxins

Definition

Mycotoxins refer to a toxic secondary metabolite produced by organisms of the kingdom Fungi and is capable of causing disease and death in both humans and other animals while aflatoxins refer to various poisonous carcinogens and mutagens that are produced by certain molds, particularly Aspergillus species.

Type

Usually, mycotoxins are toxic secondary metabolites of fungi while aflatoxins are a type of mycotoxins.

Produced by

Mycotoxins are produced by fungi while aflatoxins are produced by Aspergillus.

Toxicity

Mycotoxins can be poisonous, carcinogenic, and mutagenic while aflatoxins are carcinogenic and can cause liver cancer.

Conclusion

In brief, mycotoxins and aflatoxins are two types of poisonous substances in fungi. Mycotoxins are also carcinogenic and mutagenic. Aflatoxin, citrinin, fumonisins, ochratoxin A, and patulin some examples of mycotoxins. In contrast, aflatoxin is a type of mycotoxin that is carcinogenic. Aspergillus produces aflatoxins. Therefore, the main difference between mycotoxin and aflatoxin is their toxicity.

References:

1. Bennett JW, Klich M. Mycotoxins. Clin Microbiol Rev. 2003 Jul;16(3):497-516. doi: 10.1128/CMR.16.3.497-516.2003. PMID: 12857779; PMCID: PMC164220.

Image Courtesy:

1. “Aspergillus parasiticus UAMH3108” By Medmyco – Own work (CC BY-SA 4.0) via Commons Wikimedia
2. “(–)-Aflatoxin B1 Structural Formulae V ” By Ju – Own Work (Public Domain) via Commons Wikimedia