Part 1: Natural Mitigation of Mycotoxins – the growing options and opportunities

20-05 | |
A holistic approach, starting from prevention in the field through to proper storage and the use of effective mitigation products, will be essential. Photo: Canva
A holistic approach, starting from prevention in the field through to proper storage and the use of effective mitigation products, will be essential. Photo: Canva

Consumers want to be assured that animal products are clean and safe, so there is a growing preference for natural solutions for mycotoxin mitigation. Many manufacturers focus on natural detoxifiers, such as yeast, enzymes, plant extracts and insects.

Mycotoxins from fungal pathogen infection in feed crops are a huge problem in the global feed sector and countless dollars are spent every year to detect, measure and mitigate these compounds from the feed mill to the farm level.

But not all mitigation methods are equal. Toxin binders can contain heavy metals and other compounds that pose risks to livestock health and food safety, for example. Some methods are very energy intensive and can also negatively affect finished feed quality.

Similarly to what’s occurring with crop protection products, there is now a focus on mycotoxin mitigation using natural solutions. As noted in a new report from Reliable Business Insights examining mycotoxin detoxifiers trends to 2031, “there is a growing preference for organic and natural feed mycotoxin detoxifiers as consumers demand clean and safe animal products. Manufacturers are focusing on developing innovative detoxifiers derived from natural sources such as yeast, enzymes and plant extracts.”

Natural mitigation – how does it work?

Microbial methods of mycotoxin mitigation span several fronts. Various organisms can be used to directly absorb and metabolise toxins, adsorb/bind them or secrete enzymes that degrade toxins, as explained in a recent research paper called ‘Remediation strategies for mycotoxins in animal feed.’ A team of scientists from China and Canada list several specific microbes with these capabilities such as Lactobacillus, Bacillus and Sphingomonas species bacteria, Aspergillus fungi and Saccharomyces yeast.

Regarding the potential of fungi, Dr Hamed Abbas, a Research Plant Pathologist with the US Department of Agriculture (USDA), explains that there have not yet been any direct applications of fungi to mitigate mycotoxins that he’s aware of. However, he says “there are fungi whose genes for mycotoxin-metabolising enzymes have been extracted and inserted in bacteria in order to be mass produced.” Abbas also leads the Biological Control of Pests Research Unit at USDA Agriculture Research Service in Stoneville, Mississippi.

Fungi themselves do not get applied to mitigate toxins in grain, he notes, because there is too much uncertainty. In other words, the conditions that are favourable for growth of the mitigation species would probably also be favourable for the growth of the original toxin-producing species. Also, the mitigation species might produce other toxins as it metabolises the original toxin.

Bacteria progress

Dr Ursula Hofstetter-Schähs, Head of Global Product Management for Mycotoxin Risk Management at dsm-firmenich Animal Nutrition & Health, explains that microbial biotransformation and enzymatic degradation of mycotoxins have made promising progress over the past 20 years. Products on the market include one of her company’s offerings, which features a bacterial strain that metabolises deoxynivalenol and trichothecene mycotoxins into non-toxic metabolites.

However, she notes that “while research continues to identify new microbes and enzymes for degrading different mycotoxins, microbial adsorption has been less successful” and stresses that the distinction between adsorption (binding) and absorption (soaking up) is important, as their effectiveness varies due to the structural properties of different mycotoxins, such as polarity.

Indeed, Hofstetter-Schähs notes that adsorption has only been found to be partially effective for mycotoxins such as zearalenone and aflatoxins. “For highly-toxic aflatoxins, carefully selected clay minerals like bentonites remain the most effective binders,” she says.

And even though R&D into microbe mycotoxin mitigation continues, the level of resources required is enormous. “The specificity of these solutions means a significant commitment of time and cost to conduct the necessary research and testing,” says Hofstetter-Schähs. “This becomes particularly intensive when seeking approval from health and safety regulatory bodies, as comprehensive safety and efficacy studies are essential.

The highest potential

Among the various natural methods for mitigating mycotoxin contamination in animal feed, Hofstetter-Schähs considers biotransformation using precision enzymes the most promising.

“What sets enzymatic biotransformation apart is its precision and effectiveness in converting toxic molecules into harmless compounds, thus safeguarding animal health,” she says. She adds that recombinant enzymes derived from natural sources such as soil microbes and intestinal/rumen bacteria have proven efficient and specific in mycotoxin detoxification with measurable activity.

The decade ahead

Looking forward 5 to 10 years, Hofstetter-Schähs anticipates that natural mycotoxin mitigation strategies will probably remain aligned with current approaches, as there may not be significant advancements in ‘natural’ methods beyond what is currently already known.

She adds that “it’s unlikely that natural mycotoxin mitigation alone will become a primary remediation strategy due to increasingly stringent regulatory requirements. Instead, a holistic approach, starting from prevention measures in the field to proper storage and the use of effective mitigation products, will continue to be essential. Enzymatic detoxification remains the key component of successful mycotoxin risk management, offering targeted and measurable solutions alongside broader strategies to ensure animal health and productivity among mycotoxin challenges.”

Abbas also believes that mycotoxin mitigation is best developed with multi-faceted approaches in mind, adding that “cost and time will always be important factors that influence which method is applied and by whom.”

But there is another area of natural mycotoxin remediation that is showing great promise, says Abbas. While he acknowledges that microbe digestion, secreted enzymes and adsorption all offer unique benefits, a recent research project with a colleague has “sold” him on using insects.

“They create a useful product [they are a high-protein feed ingredient] while doing a service of getting rid of mycotoxins,” he says. “We would like to see insect farming as a key component that helps produce safe and sustainable food and feeds that reduce waste and promotes a circular economy.”

Insects, he notes, can also be used to address another mycotoxin issue somewhat outside infected crops: fermentation to produce fuel alcohol. “Yeast effectively concentrates mycotoxins in distiller’s grains, along with proteins and other components,” says Abbas. “They are another potential application for insect-based remediation.”

More research needed

However, Hofstetter-Schähs notes that, while recent studies have shown that certain insects possess the ability to metabolize mycotoxins, particularly fumonisins, the practical application of this approach remains uncertain.

“Questions regarding the efficacy and industrial viability of insect-based mycotoxin detoxification persist,” she explains. “Moreover, consumer acceptance of insect proteins remains a challenge and the cost-effectiveness of insect-derived products compared to traditional protein sources such as soybean meal may hinder widespread adoption in the livestock industry. It’s essential to thoroughly investigate the metabolic pathways of mycotoxin biotransformation in insects to determine their potential as viable mitigation strategies.”

In Part 2 of this story, we further explore the use of insects as a natural method for mycotoxin mitigation. Will go live 24 May

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Treena Hein Correspondent