The status of Fusarium mycotoxins in Sub-Saharan Africa : a review of emerging trends and post-harvest mitigation strategies towards food control

Fusarium fungi are common plant pathogens causing several plant diseases. The presence of these molds in plants exposes crops to toxic secondary metabolites called Fusarium mycotoxins. The most studied Fusarium mycotoxins include fumonisins, zearalenone, and trichothecenes. Studies have highlighted the economic impact of mycotoxins produced by Fusarium. These arrays of toxins have been implicated as the causal agents of wide varieties of toxic health effects in humans and animals ranging from acute to chronic. Global surveillance of Fusarium mycotoxins has recorded significant progress in its control; however, little attention has been paid to Fusarium mycotoxins in sub-Saharan Africa, thus translating to limited occurrence data. In addition, legislative regulation is virtually non-existent. The emergence of modified Fusarium mycotoxins, which may contribute to additional toxic effects, worsens an already precarious situation. This review highlights the status of Fusarium mycotoxins in sub-Saharan Africa, the possible food processing mitigation strategies, as well as future perspectives

Mycotoxin occurrence in maize silage : a neglected risk for bovine gut health?

Forages are important components of dairy cattle rations but might harbor a plethora of mycotoxins. Ruminants are considered to be less susceptible to the adverse health effects of mycotoxins, mainly because the ruminal microflora degrades certain mycotoxins. Yet, impairment of the ruminal degradation capacity or high ruminal stability of toxins can entail that the intestinal epithelium is exposed to significant mycotoxin amounts. The aims of our study were to assess (i) the mycotoxin occurrence in maize silage and (ii) the cytotoxicity of relevant mycotoxins on bovine intestinal cells. In total, 158 maize silage samples were collected from European dairy cattle farms. LC-MS/MS-based analysis of 61 mycotoxins revealed the presence of emerging mycotoxins (e.g., emodin, culmorin, enniatin B1, enniatin B, and beauvericin) in more than 70% of samples. Among the regulated mycotoxins, deoxynivalenol and zearalenone were most frequently detected (67.7%). Overall, 87% of maize silages contained more than five mycotoxins. Using an in vitro model with calf small intestinal epithelial cells B, the cytotoxicity of deoxynivalenol, nivalenol, fumonisin B1 and enniatin B was evaluated (0-200 mu M). Absolute IC50 values varied in dependence of employed assay and were 1.2-3.6 mu M, 0.8-1.0 mu M, 8.6-18.3 mu M, and 4.0-6.7 mu M for deoxynivalenol, nivalenol, fumonisin B1, and enniatin B, respectively. Results highlight the potential relevance of mycotoxins for bovine gut health, a previously neglected target in ruminants

In vitro rumen simulations show a reduced disappearance of deoxynivalenol, nivalenol and enniatin B at conditions of rumen acidosis and lower microbial activity

Ruminants are generally considered to be less susceptible to the effects of mycotoxins than monogastric animals as the rumen microbiota are capable of detoxifying some of these toxins. Despite this potential degradation, mycotoxin-associated subclinical health problems are seen in dairy cows. In this research, the disappearance of several mycotoxins was determined in an in vitro rumen model and the effect of realistic concentrations of those mycotoxins on fermentation was assessed by volatile fatty acid production. In addition, two hypotheses were tested: (1) a lower rumen pH leads to a decreased degradation of mycotoxins and (2) rumen fluid of lactating cows degrade mycotoxins better than rumen fluid of non-lactating cows. Maize silage was spiked with a mixture of deoxynivalenol (DON), nivalenol (NIV), enniatin B (ENN B), mycophenolic acid (MPA), roquefortine C (ROQ-C) and zearalenone (ZEN). Fresh rumen fluid of two lactating cows (L) and two non-lactating cows (N) was added to a buffer of normal pH (6.8) and low pH (5.8), leading to four combinations (L6.8, L5.8, N6.8, N5.8), which were added to the spiked maize substrate. In this study, mycotoxins had no effect on volatile fatty acid production. However, not all mycotoxins fully disappeared during incubation. ENN B and ROQ-C disappeared only partially, whereas MPA showed almost no disappearance. The disappearance of DON, NIV, and ENN B was hampered when pH was low, especially when the inoculum of non-lactating cows was used. For ZEN, a limited transformation of ZEN to alpha-ZEL and beta-ZEL was observed, but only at pH 6.8. In conclusion, based on the type of mycotoxin and the ruminal conditions, mycotoxins can stay intact in the rumen

Case study reducing mycotoxins in Brazilian crops

"Mycotoxins are toxic chemical compounds produced by molds, which can have important consequences in human and animal health... The economic consequences of the presence of mycotoxins in food, feed, and agricultural crops can be severe. In fact, mycotoxins jeopardize the safety and availability of the food supply in many countries... Both the public and private sectors in Brazil are making a concerted effort to control mycotoxins in foods consumed by both humans and animals." from TextFood safety ,food security ,Public health ,

A rapid magnetic solid phase extraction method followed by liquid chromatography-tandem mass spectrometry analysis for the determination of mycotoxins in cereals

Mycotoxins can contaminate various food commodities, including cereals. Moreover, mycotoxins of different classes can co-contaminate food, increasing human health risk. Several analytical methods have been published in the literature dealing with mycotoxins determination in cereals. Nevertheless, in the present work, the aim was to propose an easy and effective system for the extraction of six of the main mycotoxins from corn meal and durum wheat flour, i.e., the main four aflatoxins, ochratoxin A, and the mycoestrogen zearalenone. The developed method exploited magnetic solid phase extraction (SPE), a technique that is attracting an increasing interest as an alternative to classical SPE. Therefore, the use of magnetic graphitized carbon black as a suitable extracting material was tested. The same magnetic material proved to be effective in the extraction of mycoestrogens from milk, but has never been applied to complex matrices as cereals. Ultra high-performance liquid chromatography tandem mass spectrometry was used for detection. Recoveries were > 60% in both cereals, even if the matrix effects were not negligible. The limits of quantification of the method results were comparable to those obtained by other two magnetic SPE-based methods applied to cereals, which were limited to one or two mycotoxins, whereas in this work the investigated mycotoxins belonged to three different chemical classes

Assessment of dried blood spots for multi-mycotoxin biomarker analysis in pigs and broiler chickens

Dried blood spots (DBSs), a micro-sampling technique whereby a drop of blood is collected on filter paper has multiple advantages over conventional blood sampling regarding the sampling itself, as well as transportation and storage. This is the first paper describing the development and validation of a method for the determination of 23 mycotoxins and phase I metabolites in DBSs from pigs and broiler chickens using liquid chromatography-tandem mass spectrometry (LC-MS/MS). The targeted mycotoxins belong to groups for which the occurrence in feed is regulated by the European Union, namely, aflatoxins, ochratoxin A and several Fusarium mycotoxins, and to two groups of unregulated mycotoxins, namely Alternaria mycotoxins and Fusarium mycotoxins (enniatins and beauvericin). The impact of blood haematocrit, DBS sampling volume and size of the analysed DBS disk on the validation results was assessed. No effects of variation in size of the analysed disk, haematocrit and spotted blood volume were observed for most mycotoxins, except for the aflatoxins and beta-zearalanol (BZAL) at the lowest haematocrit (26%) level and for the enniatins (ENNs) at the lowest volume (40 mu L). The developed method was transferred to an LC-high resolution mass spectrometry instrument to determine phase II metabolites. Then, the DBS technique was applied in a proof-of-concept toxicokinetic study including a comparison with LC-MS/MS data from plasma obtained with conventional venous blood sampling. A strong correlation (r > 0.947) was observed between plasma and DBS concentrations. Finally, DBSs were also applied in a pilot exposure assessment study to test their applicability under field conditions

Mycotoxin food safety risk in developing countries

"Mycotoxins are produced by fungi, commonly known as mold. These toxins can develop during production, harvesting, or storage of grains, nuts, and other crops. Mycotoxins are among the most potent mutagenic and carcinogenic substances known. They pose chronic health risks: prolonged exposure through diet has been linked to cancer and kidney, liver, and immune-system disease. Because mycotoxins occur more frequently under tropical conditions and diets in many developing countries are more heavily concentrated in crops susceptible to mycotoxins, these chronic health risks are particularly prevalent in developing countries." from TextFood safety ,food security ,Public health ,

The role of mycotoxins in pig reproduction : a review

Mycotoxins are commonly present in feed for farm animals. Sows and gilts are highly susceptible to mycotoxins. This article presents a review describing the main mycotoxins encountered in pig feed which have a negative impact on sow fertility and reproduction. Consumption of feed that is contaminated with these mycotoxins may cause a variety of symptoms, depending on the type of mycotoxin, quantity and duration of exposure, as well as the health status and condition of the animal at the time of exposure. Two types of fungi are recognized, field fungi and storage fungi. Field fungi such as Fusarium spp., Aspergillus spp. and Claviceps spp. may produce toxins that lead to disturbed reproductive performance. Storage fungi occur if the humidity during storage is too high. In daily practice, the symptoms related to mycotoxicosis can occur at toxin concentrations below the detection limit. Knowledge of the effects of mycotoxins is expanding rapidly. Mycotoxins may still be present in feedstuffs despite negative analytical findings and because of the presence of hot spots in feed and or feedstuffs. Clinical symptoms can be very pronounced, making the diagnosis for the practitioner quite easy but in many cases the symptoms are vague and not at all present at herd level on a regular basis. The practitioner is in the first line of raising awareness in all parties whenever the first indication exists of a possible mycotoxicosis problem causing reproductive failure in breeding pigs. The problems can be resolved only if all parties involved in pig herd health take the necessary preventive measures and actions. The main toxins causing reproductive failure discussed in this article are aflatoxins, ergot alkaloids, trichothecenes and zearalenone

Managing mycotoxins in on farm swine feeds in the northeastern U.S.

Master of AgribusinessDepartment of Agricultural EconomicsDaniel M. O'BrienThe purpose of this thesis is to explore the possible affect that mycotoxins have on the aspects of hog production in the northeast region of the United States. Analyzing the impact of the most prevalent mycotoxins on hog health can show how a mycotoxin binder can be a positive influence on hog health and producers’ pocket. Through profiles of both mycotoxins and commonly used binders it can be shown how these unseen toxins have a lengthy and costly harmful impact on the profitability of hog production if not effectively managed. Using a partial budget economic analysis approach, demonstrates how costs associated with mycotoxins can be mitigated. This study compares the economic impact of mycotoxins in swine feed rations that contain a binder on a regular basis verses rations including binders on an as needed basis. A literary review aspect of this thesis will look at how economic models can estimate the overall economic impact of mycotoxins in the hog and livestock industries

Alternaria in food: Ecophysiology, mycotoxin production and toxicology

Alternaria species are common saprophytes or pathogens of a wide range of plants pre- and post-harvest. This review considers the relative importance of Alternaria species, their ecology, competitiveness, production of mycotoxins and the prevalence of the predominant mycotoxins in different food products. The available toxicity data on these toxins and the potential future impacts of Alternaria species and their toxicity in food products pre- and post-harvest are discussed. The growth of Alternaria species is influenced by interacting abiotic factors, especially water activity (a w ), temperature and pH. The boundary conditions which allow growth and toxin production have been identified in relation to different matrices including cereal grain, sorghum, cottonseed, tomato, and soya beans. The competitiveness of Alternaria species is related to their water stress tolerance, hydrolytic enzyme production and ability to produce mycotoxins. The relationship between A. tenuissima and other phyllosphere fungi has been examined and the relative competitiveness determined using both an Index of Dominance (I D ) and the Niche Overlap Index (NOI) based on carbon-utilisation patterns. The toxicology of some of the Alternaria mycotoxins have been studied; however, some data are still lacking. The isolation of Alternaria toxins in different food products including processed products is reviewed. The future implications of Alternaria colonization/infection and the role of their mycotoxins in food production chains pre- and post-harvest are discussed