Growth of Fungal Cells and the Production of Mycotoxins

Abstract

Some filamentous fungi are able to grow in food and produce toxic metabolites. It occurs mainly in grains, cereals, oilseeds and some by-products. The growth of fungi in a particular food is governed largely by a series of physical and chemical parameters. The production of toxic metabolites is not confined to a single group of molds irrespective of whether they are grouped according to structure, ecology, or phylogenetic relationships. Mycotoxins can be carcinogenic and cause several harmful effects to both human and animal organisms, in addition to generating large economic losses. The major mycotoxins found in food are the aflatoxins, fumonisins, ochratoxins, patulin, zearalenone, and trichothecenes, generally stable at high temperatures and long storage periods. Considering the difficult prevention and control, international organizations for food safety establish safe levels of these toxins in food destined for both human and animal consumption. Good agricultural practices and control of temperature and moisture during storage are factors which contribute significantly to inhibit the production of mycotoxins. The use of some fungistatic products, such as essential oils and antioxidants, as well as physical, mechanical, chemical, or thermal processing, represents important methods to have the concentration of mycotoxins reduced in food.

Screening of Anti-Inflammatory Activity and Metabolomics Analysis of Endophytic Fungal Extracts; Identification and Characterization of Perylenequinones and Terpenoids from the Interesting Active Alternaria Endophyte

“…Most mycotoxins exhibit toxic effects, even at low concentrations, in humans and animals [ 39 ]. Among the various secondary metabolites produced by fungi of the genus Alternaria, alternariol, alternariol 9-methyl ether and other lactones resorcylic acids or resorcylic acids are the main toxic metabolites described [ 42 , 45 , 46 ]. Although their toxicity is low compared to other mycotoxins (e.g., aflatoxins or ochratoxins), Alternaria species cause significant harvest losses of fruits, vegetables, juices and other products and can lead to allergic reactions, skin infections, keratitis and otitis in humans.…”

Fungal Growth and Mycotoxins Production: Types, Toxicities, Control Strategies, and Detoxification

“…Although the pH effect on the production of some mycotoxins has not been fully established for every type of mycotoxins, however acidic conditions are known to promote germination and production of mycotoxin. Production of aflatoxins requires pH 4.0 and the pH has inverse relationship with the level of synthesis [12]. In the same way, OTA levels are higher when Aspergillus ochraceus are at low pH [32].…”

“…In the same way, OTA levels are higher when Aspergillus ochraceus are at low pH [32]. Fumonisin B1 (FB1) is unstable in alkaline medium and requires pH 4.0-5.0 for synthesis; production of trichothecenes is initiated in acidic conditions [12].…”

“…In primary growth, organic compounds are required for the biomass synthesis and production of energy needed to drive chemical reactions to produce the primary metabolites that are essential for growth; secondary growth takes place after the phase of maintained growth and may, sometimes, lead to sporulation and secondary metabolites production [1]. The secondary metabolites, including mycotoxins, have no significant impacts on the fungal growth, but appear to be produced as a result of the excess accumulation of the precursors of primary metabolites, as a means to reduce their concentrations in the fungi [12]. As the fungi that produce mycotoxin and their targeted hosts are diverse in nature, it is difficult to define a single set of conditions which ultimately leads to mycotoxin production.…”

Biocontrol Methods in Avoidance and Downsizing of Mycotoxin Contamination of Food Crops

“…Their impact may be witnessed as early as in the field, and increase during harvesting, drying, and storage [20]. However, mold colonization does not necessarily Processes 2022, 10, 655 3 of 23 result in mycotoxin contamination, since the latter calls for specific and independent prerequisites [21,22]. On the other hand, the removal of molds from food and feed does not vouch for their absence because of their resistant chemical composition [23].…”