Abstract
Mycotoxins are secondary metabolites produced by several fungi contaminating crops. In several countries, the maximum permitted levels of mycotoxins are found in foodstuffs and feedstuffs. The common strategy of mycotoxin analysis involves extraction, clean-up and quantification by chromatography. In this paper, we analyzed the reasons of underestimation of ochratoxin A (OTA) content in wine, and overestimation of OTA in wheat, depending on the pH of the clean-up step and the simultaneous presence of citrinin (CIT). We demonstrated that the increase of pH by adding polyethylene glycol (PEG) to wine led to an underestimation of OTA by conversion of OTA into open ring ochratoxin A OP-OA. In comparing three methods of extraction and clean-up for the determination of OTA and CIT in wheat—(i) an inter-laboratory validated method for OTA in cereals using immunoaffinity column clean-up (IAC) and extraction by acetonitrile/water; (ii) a validated method using IAC and extraction with 1% bicarbonate Na; and (iii) an in-house validated method based on acid liquid/liquid extraction—we observed an overestimation of OTA after immunoaffinity clean-up when CIT is also present in the sample, whereas an underestimation was observed when OTA was alone. Under neutral and alkaline conditions, CIT was partially recognized by OTA antibodies.
Highlights
Aspergillus, Penicillium and Fusarium are fungi often found in crops
16% of ochratoxin A (OTA) was lost after PVPP, whereas the proportion of OTA apparently lost during polyethylene glycol (PEG) treatment is over 80%, but simultaneously a new peak appears at 380 nm
When we analyzed the quantity of OTA bound to PEG, we did not find more than 10% of OTA
Summary
After a period of balanced growth followed by stress conditions, fungi produce a large variety of toxic secondary metabolites called mycotoxins [1]. Aspergillus ochraceus and Penicillium citrinum are the main producers of ochratoxin A (OTA) and citrinin (CIT), respectively. OTA is found in different animal tissues [7], as well as in human blood and breast milk [8]. This mycotoxin is a powerful nephrotoxin, teratogen, immunosuppressive agent [9,10].
Sign-in/Register to view highlights & summary Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
