Aflatoxins are known to be highly toxic, as they can have serious health consequences for humans and animals. They are toxic fungal metabolites that can contaminate a wide range of food and feed crops, including peanuts, corn and tree nuts. They are produced by certain species of Aspergillus fungi, which grow on crops before or after harvest, especially under warm, humid conditions. Exposure to aflatoxins has been associated with an increased risk of various cancers, including lung and digestive cancers.
Prevention of aflatoxin contamination is a major challenge for the food and feed industries. Various strategies are used to reduce their occurrence, and understanding the mode of action of laccase is essential.
To evaluate the ability of this enzyme to detoxify aflatoxins, researchers at IRIG conducted a study based on combined experimental and theoretical approaches. First, in vitro experiments showed that laccase was able to efficiently oxidize aflatoxins, leading to their detoxification. Computer simulations were then carried out to study the mechanisms underlying the detoxification process, notably using the BigDFT code. The simulations confirmed that laccase was able to bind to aflatoxins and oxidize them through a radical-based mechanism.
Figure: indication of the oxidation sensitive areas for two different configurations of the aflatoxin molecule by showing the so-called Fukui isosurfaces. Credit CEA
The results of this study suggest that laccase may be a promising enzyme for the detoxification of aflatoxins. Further research will be needed to explore potential applications and deploy laccase-based detoxification strategies in the food industry.
BigDFT is a free software for physicists or chemists, whose main program allows to calculate the total energy and the electronic structure of systems, within density functional theory (DFT) and a wavelet basis.