Major mycotoxins occurrence, prevention and control approaches

A review on mycotoxins and mycotoxicoses in ruminants and Equidae in South America

Of the mycotoxicoses caused by molds contaminating grains or their byproducts, leukoencephalomalacia of horses and less frequently aflatoxicosis in cattle have been reported in South America. However, the most important group of mycotoxins in the region are those caused by fungi that infect forages and other types of plants and have regional distribution. In this group, ergotism is important, both caused by Claviceps purpurea infecting grains or by Epichloë coenophiala infecting Schedonorus arundinaceus. Other important mycotoxicoses are those caused by indole-diterpenes produced by Clavicipitaceous fungi including Claviceps paspali in Paspalum spp., Claviceps cynodontes in Cynodon dactylon, and by Periglandula a seed transmitted symbiont associated with the tremorgenic plant Ipomoea asarifolia. The latter is an important poisoning in the northeastern and northern Brazil. Other important mycotoxicoses are those caused by swainsonine containing plants. It was demonstrated that swainsonine contained in Ipomoea carnea var. fistulosa is produced by an epibiotic fungus of the order Chaetothyriales whose mycelia develop on the adaxial surface of the leaves. Swainsonine is also produced by the symbiotic, endobiotic fungi Alternaria section Undifilum spp., which is associated with Astragalus spp. in the Argentinian Patagonia causing poisoning. Another form of mycotoxicosis occurs in poisoning by Baccharis spp., mainly B. coridifolia, a very important toxic plant in South America that contains macrocyclic trichothecenes probably produced by an endophytic fungus that has not yet been identified. Pithomycotoxicosis caused by Pithomyces chartarum used to be an important mycotoxicosis in the region, mainly in cattle grazing improved pastures of legumes and grasses. Slaframine poisoning, diplodiosis and poisoning by barley contaminated by Aspergillus clavatus has been rarely diagnosed in Brazil, Uruguay and Argentina.

Response of broilers to dietary inclusion of atoxigenic Aspergillus flavus strain as a biocontrol strategy of aflatoxin

The objective of this trial was to evaluate how broilers responded to Aspergillus flavus strains that are toxigenic and atoxigenic. The study included four treatments in a 2 × 2 factorial design, with six replicates of 10 birds each. As a result of this study measuring feed intake (FI), weight gain (WG), feed conversion ratio (FCR), crude protein, ether extract, and crude fibre, the interaction was insignificant between the toxigenic and atoxigenic diets (P > 0.05). Consumption of toxigenic aflatoxin B1-500 ppb diet decreased FI and WG but increased FCR, and cost to produce live broiler weight (P < 0.05) compared to the control diets. The addition of atoxigenic strains to contaminated diets significantly offset (P < 0.05) the effects. Diets with or without 500 ppb toxigenic and atoxigenic A. flavus did not affect the relative weight g/100gBW of pancreas, gizzard and bursa of Fabricius. Dietary inclusion of 500 ppb toxigenic Aspergillus spp. increased the relative weight (P < 0.05) of the kidney, liver, spleen and thymus while atoxigenic dietary addition reduced the relative weight of the same organs (P < 0.05). Dietary inclusion of toxigenic and atoxigenic Aspergillus spp. did not significantly affect the haematological parameters measured (P < 0.05). Dietary inclusion of 500 ppb toxigenic Aspergillus elevated the urea, creatine, alanine aminotransferase (ALT), aspartate aminotransferase (AST) and alkaline phosphatase (ALP) in the serum of the broilers (P < 0.05). A decrease was observed when atox igenic A. flavus was used in the intervention for urea, creatinine and AST (P < 0.05), whereas an insignificant reduction was observed for ALT and ALP (P ≤ 0.05). This study concluded that dietary atoxigenic strain improved broiler performance, digestibility, and blood parameters.

PLSR-colorimetric simultaneous determination of L-Tyrosine and L-Tryptophan in different pharmaceutical and biological samples using one-pot synthesized leaf shape Ag@Ag2O core-shell nanocomposites modified by β-CD

In the present study, a simple, innovative, and economically beneficial method has been proposed for the synthesis of Ag@Ag2O core-shell nanocomposites using Acanthophora muscoides algae extract. The host-guest recognition of targets was performed by modification of the Ag@Ag2O surface using β-CD. The Ag@Ag2O- β-CD NCs were used as a colorimetric sensor to determine L-Tryptophan and L-Tyrosine using a partial least square (PLS) approach. A crystalline hybrid structure of Ag core and an Ag2O shell was confirmed by XRD, FTIR, TEM and AFM research. Also, DLS analysis and surface zeta potential spectra illustrated the aggregated nature of nanocomposites in the presence of analytes. The literature review shows that the colorimetric simultaneous determination of L-Tryptophan (L-Try) and L-Tyrosine (L-Tyr) has not been reported. The Ag@Ag2O- β-CD sensor exhibited outstanding sensing capability in a broad linear range of 2.0 -200 μM for both amino acids and low detection limit of 0.32 and 0.51 μM, for L-Try and L-Tyr, respectively. The good sensitivity and excellent selectivity regarding possible interfering species, originated from the synergistic effect of host-guest recognition in combination with colorimetric sensing. Additionally, determination of analytes in various pharmaceutical, supplement and urine samples, approved the practical applicability of the constructed sensor. The computed results confirmed that colorimetric sensing in conjunction with a PLS technique was appropriate for the precise and accurate simultaneous determination of target amino acids in complex mixtures with RMSEP less than 2.5% and recovery in the range of 103-108% with R.S.D. values less than 3%.

Mycotoxin contamination and control strategy in human, domestic animal and poultry: A review

Mycotoxins are secondary metabolites produced mainly by fungi belonging to the genera Aspergillus, Fusarium, Penicillium, Claviceps, and Alternaria that contaminate basic food products throughout the world, where developing countries are becoming predominantly affected. Currently, more than 500 mycotoxins are reported in which the most important concern to public health and agriculture include AFB1, OTA, TCTs (especially DON, T-2, HT-2), FB1, ZEN, PAT, CT, and EAs. The presence of mycotoxin in significant quantities poses health risks varying from allergic reactions to death on both humans and animals. This review brings attention to the present status of mycotoxin contamination of food products and recommended control strategies for mycotoxin mitigation. Humans are exposed to mycotoxins directly through the consumption of contaminated foods while, indirectly through carryover of toxins and their metabolites into animal tissues, milk, meat and eggs after ingestion of contaminated feeds. Pre-harvest (field) control of mycotoxin production and post-harvest (storage) mitigation of contamination represent the most effective approach to limit mycotoxins in food and feed. Compared with chemical and physical approaches, biological detoxification methods regarding biotransformation of mycotoxins into less toxic metabolites, are generally more unique, productive and eco-friendly. Along with the biological detoxification method, genetic improvement and application of nanotechnology show tremendous potential in reducing mycotoxin production thereby improving food safety and food quality for extended shelf life. This review will primarily describe the latest developments in the formation and detoxification of the most important mycotoxins by biological degradation and other alternative approaches, thereby reducing the potential adverse effects of mycotoxins.

Advances in Occurrence, Importance, and Mycotoxin Control Strategies: Prevention and Detoxification in Foods

Mycotoxins are toxic substances that can infect many foods with carcinogenic, genotoxic, teratogenic, nephrotoxic, and hepatotoxic effects. Mycotoxin contamination of foodstuffs causes diseases worldwide. The major classes of mycotoxins that are of the greatest agroeconomic importance are aflatoxins, ochratoxins, fumonisins, trichothecenes, emerging Fusarium mycotoxins, enniatins, ergot alkaloids, Alternaria toxins, and patulin. Thus, in order to mitigate mycotoxin contamination of foods, many control approaches are used. Prevention, detoxification, and decontamination of mycotoxins can contribute in this purpose in the pre-harvest and post-harvest stages. Therefore, the purpose of the review is to elaborate on the recent advances regarding the occurrence of main mycotoxins in many types of important agricultural products, as well as the methods of inactivation and detoxification of foods from mycotoxins in order to reduce or fully eliminate them.