Mycotoxin Determination in Animal Feed: An LC-FLD Method for Simultaneous Quantification of Aflatoxins, Ochratoxins and Zearelanone in This Matrix

Abstract

Mycotoxins are toxic compounds for humans and animals that are produced by fungi. Mycotoxin contamination in feed is a global safety concern and effective control of these compounds in this matrix is needed. This study proposes a simple, cost-effective analytical method based on liquid chromatography coupled with a fluorescence detector, which is suitable for the routine monitoring of some of the most important mycotoxins in feed: aflatoxins (G2, G1, B2, and B1), zearalenone, and ochratoxins A and B. Mycotoxin extraction, chromatographic separation and quantification are carried out simultaneously for all mycotoxins. The extraction procedure is performed using acetonitrile, water and orthophosphoric acid (80:19:1). Purification of the extract is carried out using an OASIS PRIME HLB solid-phase extraction cartridge followed by a dispersive liquid–liquid microextraction procedure. Aflatoxins G1 and B1 are derivatized post-column (photochemical reactor at 254 nm) to increase their signal. The method has been validated in feed for pigs, cows, sheep, and poultry with very satisfactory results. The detection limits are 2 μg/kg for aflatoxins B1 and G1, 0.64 μg/kg for aflatoxins B2 and G2, 42 μg/kg for zearalenone, and 5 μg/kg for ochratoxins A and B. These values are low enough to allow for monitoring of these mycotoxins in feed. Global recovery values were between 73.6% and 88.0% for all toxins with a relative standard deviation (RSD) % < 7%. This methodology will facilitate laboratory control and analysis of mycotoxins in feed.

Occurrence of Zearalenone and Its Metabolites in the Blood of High-Yielding Dairy Cows at Selected Collection Sites in Various Disease States

“…In the present study, ZEN and its metabolites were not detected in asymptomatic cows ( Figure 1 and Figure 3 ), which could be attributed to the rapid biotransformation of mycotoxins by ruminal microbiota or very low concentrations of ZEN in unspecified feed transmission vectors [ 6 ]. Similar results were reported in vitro by Debevere et al [ 23 ] who observed that the biotransformation of ZEN to α -ZEL and β -ZEL (only in the rumen) is highly limited at normal ruminal pH.…”

“…The evaluated herd was probably exposed to ZEN for a long period of time or continuously. In laboratory analyses, ZEN is very often detected in maize silage, green fodder and hay [ 6 , 37 ], which indicates that this mycotoxin is present in feed throughout the year. The present results point to dysfunctions of ruminal microbiota or the liver, a unique immunological site that protects the body against mycotoxins.…”

“…In dairy cows, the risk of exposure to ZEN can be assessed directly by identifying mycotoxins in the feed matrix [ 6 ], or indirectly by analyzing the respective biomarkers in biological fluids and tissues. Feed matrices are widely applied to evaluate the risk [ 7 ] resulting from e.g., the presence of ZEN and its metabolites.…”

“…However, the influence of very low, measurable concentrations of ZEN on the health status of dairy cows has never been investigated. Such mycotoxin concentrations are frequently encountered in plant materials that are used in the production of feed for dairy cattle [ 6 , 7 , 8 ].…”

Worldwide aflatoxin contamination of agricultural products and foods: From occurrence to control

“…They obtained an LOD of 0.003 µg/kg in milk, 0.07 µg/kg in yogurt, and 0.05 µg/kg in cheese, and an overall recovery rate of 83%. In another work, Muñoz‐Solano and González‐Peñas (2020) reported developing an LC‐FLD‐based method suitable for the determination of aflatoxins in animal feed. The technique's analytical characteristics were an LOD of 2 µg/kg for aflatoxins B1 and G1 and 0.64 µg/kg for aflatoxins B2 and G2 and a recovery rate of 73.6% and 88.0% for all toxins.…”