Mycotoxin contamination in cereals (original) (raw)
An overview of mycotoxin contamination in foods and its implications for human health
Toxin Reviews, 2010
Mycotoxins are natural contaminants of cereals and other food commodities throughout the world and they significantly impact human and animal health. Mycotoxins are toxic secondary metabolites produced by species of filamentous fungi growing on grains before harvest and in storage. When ingested, inhaled, or absorbed through skin, mycotoxins may reduce appetite and general performance, and cause sickness or death in humans. Mycotoxins subject to government regulation in most countries include aflatoxins, fumonisins, ochratoxins, deoxynivalenol, zearalenone, and patulin, produced by species of Aspergillus, Fusarium, and Penicillium. Aflatoxins, fumonisins, and ochratoxins pose the most serious threats to human health worldwide. This review describes the prevalence of mycotoxins in foods and its implications on human health, which may help in establishing and carrying out proper management strategies. Data from detailed investigations of food mycotoxins worldwide help provide safer food for consumption and help prioritize future research programs.
Occurrence and Co-Occurrence of Mycotoxins in Cereal-Based Feed and Food
Microorganisms
Dietary (co)-exposure to mycotoxins is associated with human and animal health concerns as well as economic losses. This study aims to give a data-based insight from the scientific literature on the (co-)occurrence of mycotoxins (i.e., parent and modified forms) in European core cereals, and to estimate potential patterns of co-exposure in humans and animals. Mycotoxins were mainly reported in wheat and maize showing the highest concentrations of fumonisins (FBs), deoxynivalenol (DON), aflatoxins (AFs), and zearalenone (ZEN). The maximum concentrations of FB1+FB2 were reported in maize both in feed and food and were above legal maximum levels (MLs). Similar results were observed in DON-food, whose max concentrations in wheat, barley, maize, and oat exceeded the MLs. Co-occurrence was reported in 54.9% of total records, meaning that they were co-contaminated with at least two mycotoxins. In the context of parental mycotoxins, co-occurrence of DON was frequently observed with FBs in m...
Mycotoxins in organic and conventional cereals and cereal products grown and marketed in Croatia
Mycotoxin research, 2017
In this study, the levels of aflatoxin B1 (AFB1), ochratoxin A (OTA), zearalenone (ZEN), deoxynivalenol (DON) and fumonisins (FUM) in unprocessed cereals (n = 189) and cereal-based products (n = 61) were determined using validated ELISA methods. All samples originated from either conventional or organic production corresponded to the 2015 harvest in Croatia. Based on the mean mycotoxin concentrations, the risk for the consumer to exceed the tolerable daily intake (TDI) for these toxins by the consumption of both types of cereals and cereal-based products was assessed. Mycotoxin contamination of organic cereals and organic cereal-based products was not significantly different (p > 0.05). Given that the exposure assessment resulted in a small fraction of the TDI (maximum: DON, 12% of TDI), the levels of the investigated mycotoxins in both types of cereals and cereal-based products from the 2015 harvest did not pose a human health hazard.
Toxins
Cereal grains are the most important food staples for human beings and livestock animals. They can be processed into various types of food and feed products such as bread, pasta, breakfast cereals, cake, snacks, beer, complete feed, and pet foods. However, cereal grains are vulnerable to the contamination of soil microorganisms, particularly molds. The toxigenic fungi/molds not only cause quality deterioration and grain loss, but also produce toxic secondary metabolites, mycotoxins, which can cause acute toxicity, death, and chronic diseases such as cancer, immunity suppression, growth impairment, and neural tube defects in humans, livestock animals and pets. To protect human beings and animals from these health risks, many countries have established/adopted regulations to limit exposure to mycotoxins. The purpose of this review is to update the evidence regarding the occurrence and co-occurrence of mycotoxins in cereal grains and cereal-derived food and feed products and their heal...
Bulletin of University of Agricultural Sciences and Veterinary Medicine Cluj-Napoca. Agriculture
The paper aims to emphasize the last decade status of the most frequent mycotoxic contaminants of the common crop cereals: maize, wheat, barley, two row barley, soy, rye, etc. The structure of the main mycotoxins treated in this paper (ochratoxine, zearalenone, aflatoxine, trichotecene, patulin, fumonisine) is presented, mentioning the producing organisms. The limits stipulated by Romanian authorities are comparatively presented with those present in EU. The importance of the environmental factors (clime, temperature, moisture, storage conditions, etc.) on mycotoxic cereal contamination is also treated.
Food Industrial Processes - Methods and Equipment, 2012
The term mycotoxin was used for the first time in 1961 in the aftermath of a veterinary crisis in England, during which thousands of animals died. The disease was linked to a peanut meal, incorporated in the diet, contaminated with a toxin produced by the filamentous fungus Aspergillus flavus (Bennet & Klich, 2003; Richard, 2007). In general, mycotoxins are low-molecular-weight compounds that are synthetized during secondary metabolism by filamentous fungi; their chemical structure may range from simple C4 compounds to complex substances (Paterson & Lima, 2010). Mycotoxins are natural contaminants in raw materials, food and feeds. Mould species that produce mycotoxins are extremely common, and they can grow on a wide range of substrates under a wide range of environmental conditions; they occur in agricultural products all around the world (Bennet & Klich, 2003). Many mycotoxins may be toxic to vertebrates and other animal groups and, in low concentrations, some of them can cause autoimmune illnesses, and have allergenic properties, while others are teratogenic, carcinogenic, and mutagenic (Bennet & Klich, 2003; Council for Agricultural Science and Technology [CAST], 2003). Apparently, mycotoxins have no biochemical significance on fungal growth; they may have developed to provide a defense system against insects, microorganisms, nematodes, animals and humans (Etzel, 2002). Exposure to mycotoxins may occur through ingestion, inhalation, and dermal contact, and it is almost always accidental. Most cases of mycotoxicoses (animals and humans) result from eating contaminated food. Human exposure can be direct via cereals or indirect via animal products (e.g. meat, milk and eggs) (CAST, 2003). Most mycotoxins are relatively heat-stable within the conventional food processing temperature range (80-121°C), therefore so little or no destruction occurs under normal cooking conditions, such as boiling and frying, or even following pasteurization (Milicevic et al., 2010). The stability of mycotoxins during food processing has been reviewed in the work by Bullerman & Bianchini (2007). In general, the application of a food process reduces mycotoxin concentrations significantly, but does not eliminate them completely. The food processes that have been examined include physical treatments (cleaning and milling) and thermal processing (e.g. cooking, baking, frying, roasting and extrusion). The different treatments have various effects on mycotoxins, and those that utilize the highest temperatures have the greatest effects: roasting or cooking at high temperatures (above 150 °C) appear to reduce mycotoxin concentrations significantly (Bullerman & Bianchini, 2007). www.intechopen.com Food Industrial Processes-Methods and Equipment 170 It has been estimated that 25% of the world's crops are affected by fungal growth, and commodities may be, both pre-and post-harvest, contaminated with mycotoxins. The mycotoxins that can be expected in food differ from country to country in relation to the different crops, agronomic practices and climatic conditions (Bryden, 2007). Since climate changes affect the growth of mycotoxigenic fungi, mycotoxin production is also influenced (Magan et al., 2003). Currently, more than 400 mycotoxins are known. Scientific attention has mainly focused on those that have proven to be carcinogenic and/or toxic in humans and animals. Five classes of mycotoxins are considered the most significant in agriculture and in the food industry: aflatoxins (aflatoxin B1), ochratoxins (ochratoxin A), fumonisins (fumonisin B1), zearalenone, and patulin which are derived from polyketide (PK) metabolism, and trichothecenes (deoxynivalenol), whose biosynthetic pathway is of terpenoid origin. PKs are metabolites that are derived from the repetitive condensation of acetate units or other short carboxylic acids, via an enzymatic mechanism that is similar to that responsible for fatty acid synthesis (Huffman et al., 2010). Aflatoxin, ochratoxin, fumonisin, trichothecene, zearalenone and patulin are the most widespread mycotoxins in animal feed and human food. The chemical structure, biosynthetic pathway, mycotoxigenic fungi, the influence of environmental factors and toxicology will be briefly described for each class. Zearalenone will not be dealth with in the present work as, because of its hormonal activity, there is considerable knowledge about ZEA and its derivatives which can be found in the literature on growth hormones. 1.1 Toxigenic fungi Aspergillus, Alternaria, Claviceps, Fusarium, Penicillium and Stachybotrys are the recognized genera of mycotoxigenic fungi (Milicevic et al., 2010; Reddy et al., 2010). Many of these genera are ubiquitous and, in some cases, apparently have a strong ecological link with human food supplies. The natural fungal flora associated with food production is dominated by the Aspergillus, Fusarium and Penicillium genera (Sweeney & Dobson, 1998). Fusarium species are pathogens that are found on cereal crops and other commodities, and they produce mycotoxins before, or immediately after, the harvest. Some species of Aspergillus and Penicillium are also plant pathogens or commensals, but these genera are more commonly associated with commodities and food during drying and storage (Pitt, 2000). Toxigenic moulds are known to produce one or more of these toxic secondary metabolites. However, not all moulds are toxigenic and not all secondary metabolites from moulds are toxic. Many fungi produce several mycotoxins simultaneously, especially Fusarium species. Moreover, recent studies have demonstrated that the necrotrophic pathogens of wheat, Stagonospora nodorum, Pyrenophora tritiirepentis and Alternaria alternata, are also capable of synthesizing an array of mycotoxic compounds during disease development (Solomon, 2011). Nowadays, the identification and quantification of mycotoginenic fungi are carried out by PCR. Diagnostic PCR-based systems are now available for all of the most relevant toxigenic fungi: producers of aflatoxins, trichotecenes, fumonisins and patulin (Niessen, 2007; Paterson, 2006). The primers for mycotoxin pathway sequences have been reviewed in the work by Paterson (2006). 1.2 Influence of environmental factors on mycototoxin production The production of mycotoxins is highly susceptible to temperature, moisture, water activity (a w), pH and oxygen concentration, the same environmental factors that affect the growth of www.intechopen.com Mycotoxins in Food 171 toxygenic fungi. Moisture and temperature are two factors that have a crucial effect on fungal proliferation and toxin biosynthesis (Bryden, 2007; Paterson & Lima, 2010). The incidence and level of mycotoxin contamination are closely related to the geographic position and to seasonal factors as well as to the cultivation, harvesting, stocking, and transport conditions (Milicevic et al., 2010). Mycotoxin contaminations can be divided into the one that occurs in the developing crop (preharvest) and the one that develops after maturation (post-harvest). In the pre-harvest period, preventive measures are included in good agronomic practices, such as the careful use of insecticides and fungicides, irrigation to avoid moisture stress, harvesting at maturity and improvement by genetic resistance to fungal attack. During the post-harvest period, the control of the moisture and temperature of the stored commodity will largely determine the degree of fungal activity and consequently the mycotoxin synthesis (Bryden, 2007). Treatments with chemicals, including sodium bisulfite, ozone, and ammonia, acids and bases, represent an opportunity to control fungal growth and mycotoxin biosynthesis in stored grains (Bozoglu, 2009; Magan, 2006; Magan & Aldred, 2007). In recent years, a good control of mycotoxigenic fungi has been achieved using plant products (e.g. extracts and essential oils) as environmental friendly fungicides (Nguefacka et al., 2004; Reddy et al., 2010; Thembo et al., 2010). Moreover, biological control represents a new opportunity in control strategies: there is evidence that Bacillus sp., propionic acid bacteria and lactic acid bacteria (LAB) are able to inhibit fungal growth and mycotoxin production (Bianchini & Bullerman, 2010). 1.3 Toxicology and health Mycotoxins are toxic to vertebrates and humans at low concentrations. Mycotoxicoses in humans or animals have been characterized as food or feed related, non-contagious, nontransferable, and non-infectious (Zain, 2011). Mycotoxins have various acute and chronic effects on humans and animals, depending on the species. Within a given species, the impact of mycotoxins on health is influenced by age, sex, weight, diet, exposure to infectious agents, and the presence of other mycotoxins (synergistic effects) and pharmacologically active substances (Milicevic et al., 2010; Zain, 2011). The majority of mycotoxins currently known are grouped, according to their toxic activity, under chronic conditions as mutagenic, carcinogenic or teratogenic. Grouping according to their site of action results in hemo-, hepato-, nephron-, dermato-, neuro-or immunotoxins (Niessen, 2007). The most important mycotoxins worldwide are aflatoxins, fumonisins, ochratoxins, deoxinyvalenol and zearalenone. Carcinogenic properties have been recognized with regard to aflatoxin and fumonisins (Mazzoni et al., 2011; Wogan, 1992). Aflatoxin B1 (AFB1) has been linked to human primary liver cancer, in which it acts synergistically with HBV infection and it has been classified as a carcinogen in humans (Group 1 carcinogen). Fumonisin B1, the most abundant of the numerous fumonisin analogues, was classified as a Group 2B carcinogen (possibly carcinogenic to humans) (Zain, 2011; Wild & Gong, 2010). The potential role of dietary factors to counteract the toxic effects of mycotoxins has been reviewed by Galvano et al. (2001): the effect of antioxidants, food components and additives on reducing toxicity, by...
Mycotoxins in cereal-based products during 24 years (1983–2017): A global systematic review
Trends in Food Science & Technology, 2019
Background: Cereal and cereal-based products are used as an important sources of energy and minerals as well as vitamins in all of the world. However, their contamination with mycotoxins reserved huge concerns due to adverse effects of mycotoxin on human health. Scope and approach: The present research was undertaken to evaluate published studies regarding the identification of mycotoxins zearalenone (ZEN), ochratoxin A (OTA), deoxynivalenol (DON), and total aflatoxin (TAF) in the cereal-based products between 1
Exposure estimates to Fusarium mycotoxins through cereals intake
Chemosphere, 2013
Screening of ten mycotoxins in 159 cereal-based products was carried out by GC-MS/MS. 65.4% of samples showed contamination by one mycotoxin and 15.7% co-occurrence. Probable daily intake were below tolerable daily intake for average consumers. Infants, children and high consumers could exceed the safety limits of some mycotoxin. A vigilant attitude to minimize human intake of mycotoxins is required.