Co-Occurrence of Regulated and Emerging Mycotoxins in Corn Silage: Relationships with Fermentation Quality and Bacterial Communities

Abstract

Sixty-four corn silages were characterized for chemicals, bacterial community, and concentrations of several fungal metabolites. Silages were grouped in five clusters, based on detected mycotoxins, and they were characterized for being contaminated by (1) low levels of Aspergillus- and Penicillium-mycotoxins; (2) low levels of fumonisins and other Fusarium-mycotoxins; (3) high levels of Aspergillus-mycotoxins; (4) high levels of non-regulated Fusarium-mycotoxins; (5) high levels of fumonisins and their metabolites. Altersetin was detected in clusters 1, 3, and 5. Rugulusovin or brevianamide F were detected in several samples, with the highest concentration in cluster 3. Emodin was detected in more than 50.0% of samples of clusters 1, 3 and 5, respectively. Kojic acid occurred mainly in clusters 1 and 2 at very low concentrations. Regarding Fusarium mycotoxins, high occurrences were observed for FB3, FB4, FA1, whereas the average concentrations of FB6 and FA2 were lower than 12.4 µg/kg dry matter. Emerging Fusarium-produced mycotoxins, such as siccanol, moniliformin, equisetin, epiequisetin and bikaverin were detected in the majority of analyzed corn silages. Pestalotin, oxaline, phenopirrozin and questiomycin A were detected at high incidences. Concluding, this work highlighted that corn silages could be contaminated by a high number of regulated and emerging mycotoxins.

Changes of Milk Metabolomic Profiles Resulting from a Mycotoxins-Contaminated Corn Silage Intake by Dairy Cows

“…Interestingly, some fungal metabolites were detected, such as alpha-zearalenol, beauvericin, cyclopenin, and tentoxin ( Table S1 ). Some of the fungal metabolites have been detected also in the corn silages previously analyzed by Gallo et al [ 10 ] for their mycotoxins’ contamination profile, thus revealing potential carry-over phenomena that deserve future ad-hoc studies. Besides, the analysis of pooled quality control samples allowed to confirm the identity of 325 milk metabolites structurally also, according to spectral MS/MS marching and/or in silico annotations ( Table S1 ).…”

“…Going into details, ruminants can be less severely affected by certain mycotoxins compared to monogastrics, which is attributed to the microbial activity in the rumen that can modify mycotoxins into less toxic compounds [ 8 , 9 ]. In the last years, several works have deepened the co-occurrence of regulated and emerging mycotoxins in corn silages, by focusing on different parameters, such as fermentation quality and bacterial communities [ 7 , 10 , 11 ]. Regarding the available literature describing cow milk as a function of the mycotoxins’ contamination of corn silage, Signorini et al [ 12 ] developed a simulation model to carry out a risk exposure assessment of the mycotoxin level (namely aflatoxin B1, deoxynivalenol, and zearalenone) in cow’s milk produced in Argentina.…”

“…Based on this, untargeted metabolomics based on UHPLC-Orbitrap mass spectrometry was used in this work to examine milk samples collected from dairy farms using a corn silage feeding systems. The corn silages were previously classified in five main clusters according to the mycotoxins’ contamination [ 10 ]. Therefore, metabolomics followed by multivariate statistics are expected to provide new insights into the chemical perturbations of milk metabolome, as induced by both high- and low-mycotoxins contaminated corn silages feeding systems.…”

Mycotoxins, Phytoestrogens and Other Secondary Metabolites in Austrian Pastures: Occurrences, Contamination Levels and Implications of Geo-Climatic Factors

“…The pasture samples contained 17 compounds considered emerging mycotoxins [ 37 , 38 , 39 ]. The majority of these emerging mycotoxins were derived from the genera Fusarium (in total 14 classified as emerging toxins) and, to a lesser extent, from Alternaria (2) and Aspergillus (1) ( Table 1 ).…”

“… 1 n = 18 pastures, samples with values > limit of detection (LOD); 2 Excluding data < LOD. In case values > LOD and <limit of quantification (LOQ), LOQ/2 was used for calculation; 3 emerging mycotoxins [ 37 , 38 , 39 ], 4 accumulative values of occurrences and concentrations of all the metabolites belonging to the group, 5 regulated mycotoxins (European Commission, 2002, 2006, 2012) [ 18 , 19 , 20 ] and 6 modified mycotoxins [ 21 ]. …”