Survey of mycotoxins in Southern Brazilian wheat and evaluation of immunoassay methods
AUTOR(ES)
Duffeck, Maíra Rodrigues, Tibola, Casiane Salete, Guarienti, Eliana Maria, Del Ponte, Emerson Medeiros
FONTE
Sci. agric. (Piracicaba, Braz.)
DATA DE PUBLICAÇÃO
2017-08
RESUMO
ABSTRACT One hundred commercial wheat grain samples were collected during the 2015 sea-son across 78 municipalities in the states of Paraná (PR), Rio Grande do Sul (RS), and São Paulo (SP), Brazil. Separate subsamples were analyzed for the concentration of deoxynivalenol (DON), zearalenona (ZEA) and ochratoxin A (OTA) mycotoxins using two methods: UHPLC-MS/MS (reference method) and a commercial enzyme-linked immunosorbent assay (ELISA) (AgraQuant®). The OTA mycotoxin was not found in the samples by both methods. DON and ZEA were detected in 55 % and 39 % of the samples by the reference method, with overall mean levels of 795.2 μg kg−1 and 79.78 μg kg−1, respectively. There was a significant and positive correlation (Spearman rank) between DON and ZEA estimates by the reference method (r = 0.77, p < 0.001). The DON levels estimated by the immunoassay agreed poorly with the reference, being largely overestimated. Based on a cut-off level of 1000 μg kg−1, the immunoassay correctly classified 57 samples as true negatives and 15 as true positives. Only 28 were classified as false positives. For ZEA, the levels estimated by the two methods were in better agreement than for DON. Using the cut-off level of 200 μg kg−1, 96 % of the samples were classified correctly as true positives and only one sample was classified as false positive. The levels for both mycotoxins were mostly acceptable for human consumption. Further studies should focus on multi-toxin methods compared with immunoassays to understand the reasons of overestimation and the role of immunoassays as a cost-effective solution for fast screening of mycotoxins in the food chain.
Documentos Relacionados
- Folic acid and iron evaluation in Brazilian enriched corn and wheat flours
- Fusarium and Aspergillus mycotoxins contaminating wheat silage for dairy cattle feeding in Uruguay
- Laboratory evaluation of five assay methods for vancomycin: bioassay, high-pressure liquid chromatography, fluorescence polarization immunoassay, radioimmunoassay, and fluorescence immunoassay.
- Mycological survey of Korean cereals and production of mycotoxins by Fusarium isolates.
- Comparison of cytotoxicity and thin-layer chromatography methods for detection of mycotoxins.