Animal Feed Testing

Li, Hui, et al. Talanta 270 (2024): 125569.

Aflatoxins come in several different forms, including aflatoxin B1, B2, G1, G2, M1, and M2. Among these, aflatoxin B1 (AFB1) is considered the most toxic and carcinogenic. In fact, the International Agency for Research on Cancer (IARC) has classified AFB1 as a Group 1 carcinogen, meaning it is known to cause cancer in humans. According to U.S. federal law, the total aflatoxin content in dairy cattle feed must not exceed 20 ppb, and the total aflatoxin content in other animal feeds must not exceed 300 ppb.

Eu-doped nanobeads were conjugated with anti-AFB1 antibodies to prepare Eu-anti-AFB1 mAb, which can specifically recognize AFB1 in the samples. Then, AFB1-BSA antigen-modified Fe₃O₄ magnetic beads (Fe₃O₄-BSA-AFB1) were added to the above solution, and through a homogeneous competitive immunoassay, they bound to the excess Eu-anti-AFB1 mAb, forming Eu-anti-AFB1 mAb-AFB1-BSA-Fe₃O₄. Subsequently, the Eu-anti-AFB1 mAb-AFB1-BSA-Fe₃O₄ complex was separated from the solution by magnetic separation, redispersed in PBS buffer, and the fluorescence intensity was measured. It was found that as the AFB1 concentration increased, the logarithm of the AFB1 concentration showed a linear relationship with the decrease in the fluorescence of Eu-anti-AFB1 mAb-AFB1-BSA-Fe₃O₄, enabling the quantitative detection of AFB1 in feed samples.

Dzuman, Zbynek, et al. Talanta 121 (2014): 263-272.

Currently, legislation has only regulated the concentrations of selected mycotoxins in animal feeds - the European Commission Directive 2002/32/EC sets the maximum content of aflatoxin B1, and the European Commission Recommendation 2006/576/EC recommends limits for ochratoxin A, deoxynivalenol, zearalenone, fumonisins B1 and B2. However, the range of mycotoxins that can potentially contaminate animal feeds is quite extensive.

Using high-throughput methods, a reliable detection and quantification of 56 mycotoxins from Fusarium, Aspergillus, Penicillium, and Claviceps species were performed in various animal feed samples, including grains, compound feeds, extracted oilcakes, fermented silages, malted grains or dried distiller's grains with solubles (DDGS).

Wu, Bing, et al. Microchemical Journal 202 (2024): 110757.

Deoxynivalenol (DON), also known as vomitoxin, is a type B trichothecene mycotoxin primarily produced by fungi including Fusarium graminearum, F. culmorum, F. cerealis, F. crookwellense, and F. pseudograminearum. Contamination of feed ingredients by DON causes significant losses each year, rendering large amounts of feed unusable and severely impacting livestock production.

Nanozymes, with their simple synthesis, high stability, and tunable enzyme activity, have proven to be a valuable tool in colorimetric analysis due to their effectiveness in inducing substrate color changes. In this study, iron-copper nanozymes with laccase-like activity were synthesized using terephthalic acid as an organic ligand via a one-pot hydrothermal method. Interestingly, the introduction of deoxynivalenol (DON) enhanced the laccase activity, resulting in a significant intensification of the substrate color.