Mycotoxin contamination of crops poses a severe threat to global food and feed supply, but biotechnology progress to counter the problem faces “multiple bottlenecks,” according to experts.
In a review of progress in tackling the six most common mycotoxins in food and feed, Chinese researchers laid out the stark scale of the problem: approximately a quarter of global food and feed production is affected by the toxins, with their health effects through the food chain potentially serious.
The contamination, which is caused by the compounds produced by moulds, with aflatoxins perhaps the most notorious among them, can occur throughout the life of crops. It is reported to be particularly high in countries such as China, Algeria and South Africa, with climate change also linked to increased prevalence of the problem.
Promising signs, though limits remain
To date, techniques to counter the problem have fallen into the categories of biological prevention, absorption, transformation and therapy.
In terms of prevention, several fungal strains have been used with some success before harvest or during storage, to compete with toxin-releasing microorganisms. Absorption has been one of the preferred tactics to date, with the residues of crops such as grapes and almonds proving effective, as well as yeasts.
Transformation is a promising approach where the likes of bacteria, fungi and enzymes transform mycotoxins into less toxic or non-toxic products. Further research has show that biological extracts such as those from lemon balm and oregano can provide ‘therapy’ by inhibiting key processes which produce the toxins.
As a result of scientists’ positive observations, work on solutions has gradually become “an important direction of biological control research.” However, despite these efforts, progress has been limited by several factors, they wrote in the journal Animals and Zoonoses.
Key issues to contend with include a lack of long-term ecological risk data and products which can tackle co-contamination, with most current products limited to single toxins. There are also problems with scalability, they said, as in the field, often laboratory results cannot be replicated due to substrates like feeds impeding biological processes. Further, affordability remains a problem, with the cost of high-quality enzyme preparations currently high.
Multiple benefits in prospect
Addressing these roadblocks, they laid out four key ‘research dimensions’ to focus the scientific community working in this area.
These are: making the biological control effects of microbial strains even stronger using screening and gene editing, bringing nanomaterials into absorption products to increase their effectiveness, tapping the potential of multi-enzyme reactions to tackle co-contamination, and biological treatment plans working with gut intestinal microbiota in livestock, the latter which the authors described as “the most revolutionary biological therapy.”
The scientists said that they hoped their review could serve as a reference for those striving to tackle food and feed pollution.
“The integration and innovation of these technical routes will promote the strategic transformation of mycotoxin control from passive treatment to active prevention, from single function to system regulation, and ultimately achieve multi-targeted optimisation of food safety, environmental friendliness, and economic benefits,” they added.
