Negative Effects of Occurrence of Mycotoxins in Animal Feed and Biological Methods of Their Detoxification: A Review

Secondary metabolic products of molds, called mycotoxins, negatively affect animal health and production. They constitute a significant problem in veterinary and medical sciences, and their presence has been confirmed in feed all over the world. Applying appropriate agricultural practices and ensuring proper storage conditions significantly reduces the contamination of agricultural products with mycotoxins. However, this does not guarantee that raw materials are completely free from contamination. Many detoxification methods are currently used, but their insufficient effectiveness and negative impact on the quality of the raw material subjected to them significantly limits their usefulness. The positive results of eliminating mycotoxins from many products have been proven by the specific properties of microorganisms (bacteria, yeast, and fungi) and the enzymes they produce. Biological detoxification methods seem to offer the most promising opportunities to solve the problem of the presence of mycotoxins in animal food. This work, based on literature data, presents the health risks to farm animals consuming mycotoxins with feed and discusses the biological methods of their purification.

Research progress on the application of different preservation methods for controlling fungi and toxins in fruit and vegetable

Fruits and vegetables are susceptible to fungal infections during picking, transportation, storage and processing, which have a high potential to produce toxins. Fungi and toxins can cause acute or chronic poisoning after entering the body. In the field of fruit and vegetable preservation, technologies such as temperature control, modified atmosphere, irradiation, application of natural or chemical preservatives, and edible films are commonly used. In practical applications, according to the types, physiological differences and actual needs of fruits and vegetables, suitable preservation methods can be selected to achieve the effect of preservation and control of fungi and toxins. The starting point of fresh-keeping technology is to delay post-harvest senescence of fruits and vegetables, inhibit the respiratory intensity, and control the reproduction of microorganisms, which is important to control the reproduction of fungi and the production of toxins. From the three directions of physical, chemical and biological means, the article analyses and explores the effects of different external factors on the production of toxins and the effects of different preservation techniques on fungal growth and toxin production in fruits and vegetables, in order to provide new ideas for the preservation of fruits and vegetables and the control of harmful substances in food.

Influence of Biotreatment on Hordeum vulgare L. Cereal Wholemeal Contamination and Enzymatic Activities

Crop contamination with mycotoxins is a global problem with a negative impact on human and animal health as well as causing economical losses in food and feed chains. This study was focused on the evaluation of the effect of lactic acid bacteria (LAB) strain (Levilactobacillus brevis-LUHS173, Liquorilactobacillus uvarum-LUHS245, Lactiplantibacillus plantarum-LUHS135, Lacticaseibacillus paracasei-LUHS244 and Lacticaseibacillus casei-LUHS210) fermentation on the changes in the level of deoxynivalenol (DON) and its conjugates in Fusarium spp.-contaminated barley wholemeal (BWP). Samples, with different contamination of DON and its conjugates, were treated separately (for 48 h). In addition to mycotoxin content, enzymatic activities (amylolytic, xylanolytic, and proteolytic) of BWP (before and after fermentation) were evaluated. It was established that the effect of decontamination depends on the LAB strain used, and a significant reduction in DON and the concentration of its conjugates in Lc. casei fermented samples was achieved: the amount of DON decreased on average by 47%, and the amount of D3G, 15-ADON and 3-ADON decreased by 82.4, 46.1, and 55.0%, respectively. Lc. casei also showed viability in the contaminated fermentation medium and an effective production of organic acids was obtained. Additionally, it was found that enzymes are involved to the detoxification mechanism of DON and its conjugates in BWP. These findings indicate that fermentation with selected LAB strains could be applied for contaminated barley treatment in order to significantly reduce Fusarium spp. mycotoxin levels in BWP and improve the sustainability of grain production.

T-2 Toxin-The Most Toxic Trichothecene Mycotoxin: Metabolism, Toxicity, and Decontamination Strategies

Among trichothecenes, T-2 toxin is the most toxic fungal secondary metabolite produced by different Fusarium species. Moreover, T-2 is the most common cause of poisoning that results from the consumption of contaminated cereal-based food and feed reported among humans and animals. The food and feed most contaminated with T-2 toxin is made from wheat, barley, rye, oats, and maize. After exposition or ingestion, T-2 is immediately absorbed from the alimentary tract or through the respiratory mucosal membranes and transported to the liver as a primary organ responsible for toxin's metabolism. Depending on the age, way of exposure, and dosage, intoxication manifests by vomiting, feed refusal, stomach necrosis, and skin irritation, which is rarely observed in case of mycotoxins intoxication. In order to eliminate T-2 toxin, various decontamination techniques have been found to mitigate the concentration of T-2 toxin in agricultural commodities. However, it is believed that 100% degradation of this toxin could be not possible. In this review, T-2 toxin toxicity, metabolism, and decontamination strategies are presented and discussed.

Does the treatment of dried herbs with ozone as a fungal decontaminating agent affect the active constituents?

Herbs and spices are food crops susceptible to contamination by toxigenic fungi. Ozone, as a decontamination approach in the industry, has attractive benefits over traditional food preservation practices. A contribution to the studying of ozone as an antifungal and anti-mycotoxigenic agent in herbs and spices storage processes is achieved in this research. Nine powdered sun-dried herbs and spices were analyzed for their fungal contamination. The results indicate that licorice root and peppermint leaves were found to have the highest population of fungi while black cumin and fennel record the lowest population. The most dominant fungal genera are Aspergillus, Penicillium, Fusarium, and Rhizopus. Ozone treatment was performed at a concentration of 3 ppm applied for exposure times of 0, 30, 90, 150, 210, and 280 min. After 280 min of exposure to ozone, the reduction of fungal count ranged from 96.39 to 98.26%. The maximum reduction in spore production was achieved in the case of A. humicola and Trichderma viride exposed for 210 min ozone gas. There was a remarkable reduction in the production of the total mycotoxin, reaching 24.15% in aflatoxins for the 150 min-treated inoculum in the case of A. flavus. The total volume of essential oil of chamomile and peppermint was reduced by 57.14 and 26.67%, respectively, when exposed to 3 ppm. For 280 min. In conclusion, fumigation with ozone gas can be used as a suitable method for achieving sanitation and decreasing microbial load in herbs and spices. Still, it is crucial to provide precautions on ozone's effect on major active constituents before recommending this method for industrial application.

Mycotoxins in Feed and Food and the Role of Ozone in Their Detoxification and Degradation: An Update

Mycotoxins are secondary metabolites produced by some filamentous fungi, which can cause toxicity in animal species, including humans. Because of their high toxicological impacts, mycotoxins have received significant consideration, leading to the definition of strict legislative thresholds and limits in many areas of the world. Mycotoxins can reduce farm profits not only through reduced crop quality and product refusal, but also through a reduction in animal productivity and health. This paper briefly addresses the impacts of mycotoxin contamination of feed and food on animal and human health, and describes the main pre- and post-harvest systems to control their levels, including genetic, agronomic, biological, chemical, and physical methods. It so highlights (i) the lack of effective and straightforward solutions to control mycotoxin contamination in the field, at pre-harvest, as well as later post-harvest; and (ii) the increasing demand for novel methods to control mycotoxin infections, intoxications, and diseases, without leaving toxic chemical residues in the food and feed chain. Thus, the broad objective of the present study was to review the literature on the use of ozone for mycotoxin decontamination, proposing this gaseous air pollutant as a powerful tool to detoxify mycotoxins from feed and food.

Acoustic-Based Screening Method for the Detection of Total Aflatoxin in Corn and Biological Detoxification in Bioethanol Production

Aspergillus spp. are widely occurring fungi in nature; they produce toxic compounds such as aflatoxins (AFs) and mainly target plant products such as corn and nuts. The development of prevention strategies is challenging because AFs are highly toxic and have been regulated to small concentrations. This study proposes a new strategy of AF prevention through the application of rapid methods using acoustic techniques in combination with fermentation for the elimination of contaminated corn from bioethanol production processes. An acoustic device was used for the analysis of model systems consisting of corn and nuts (hazelnuts and peanuts) contaminated with different amounts of AFs. High correlations were obtained between penetrated acoustic signal amplitude (Ap) and corn sample density, and between Ap and AF content. Also, relationships were found between changes in Ap values and AF contamination in the nuts model systems. The results of biotreatment of contaminated corn during bioethanol production confirmed that AFs cannot be completely eliminated in dried distiller’s grains with solubles, a valuable by-product for animal feed. Microbially, contamination of the raw material has a negative impact on bioethanol quality by increasing the content of volatile compounds. Therefore, the application of methods such as acoustic screening is a promising alternative for rapid AF detection in corn and nuts (it can handle multi-layers of grain). With the application of acoustic techniques, the prevention of AFs in contaminated raw plant materials could be achieved.

Fusarium head blight and mycotoxins in wheat: prevention and control strategies across the food chain

With 744 million metric tons produced in 2017/2018, bread wheat (Triticum aestivum) and durum wheat (Triticum durum) are the second most widely produced cereal on a global basis. Prevention or control of wheat diseases may have an enormous impact on global food security and safety. Fusarium head blight is an economically debilitating disease of wheat that reduces the quantity and quality of grain harvested, and may lead to contamination with the mycotoxin deoxynivalenol, which affects the health of humans and domesticated animals. Current climate change scenarios predict an increase in the number of epidemics caused by this disease. Multiple strategies are available for managing the disease including cultural practices, planting less-susceptible cultivars, crop rotation, and chemical and biological controls. None of these strategies, however, is completely effective by itself, and an integrated approach incorporating multiple controls simultaneously is the only effective strategy to limit the disease and reduce deoxynivalenol contamination in human food and animal feed chains. This review identifies the available tools and strategies for mitigating the damage that can result from Fusarium head blight.