Detoxification of ochratoxin A and zearalenone by Pleurotus ostreatus during in vitro gastrointestinal digestion

Powdered Pleurotus ostreatus (PO) was tested for the detoxification of ochratoxin A (OTA) and zearalenone (ZEN) through in vitro gastrointestinal digestion in the absence and presence of ground feed and cornmeal. Ochratoxin alpha was detected in the chromatograms after OTA elimination, suggesting the presence of an OTA-hydrolytic enzyme in the PO, whereas ZEN was adsorbed by PO. OTA was totally eliminated at pH 5 and 7, while ZEN was better adsorbed at pH 3. In simulated gastrointestinal conditions conducted without feed matrices, PO eliminated OTA by 85% and ZEN by 23% at the end of the intestinal phase. When digestions were conducted with ground feed and cornmeal, PO eliminated OTA by 13 and 34%, and ZEN by 20 and 2%, respectively. PO demonstrated great potential for OTA detoxification, but the feed matrices adsorbed the mycotoxins, reducing their bioaccessibility considerably in the oral and gastric phases and negatively influencing PO detoxification capacity.

Automated summary

In this study, it was found that powdered Pleurotus ostreatus has the potential to detoxify ochratoxin A and zearalenone through in vitro gastrointestinal digestion. The presence of an OTA-hydrolytic enzyme in the PO was observed, which could eliminate OTA, while ZEN was adsorbed by PO. However, the presence of feed matrices significantly reduced the bioaccessibility of mycotoxins and negatively affected the detoxification capacity of PO.