Bioaccessibility of ochratoxin a from red wine in an in vitro dynamic gastrointestinal model

Abstract

Ochratoxin A (OTA) is a mycotoxin produced by Aspergillus and Penicillium species with immunosuppressive, teratogenic, and carcinogenic properties. It has been determined that wine is the second largest source of OTA (10% of total OTA intake) in the European diet and that its presence, even in small doses, can be a problem in terms of long-term toxicity. In this paper, we evaluated the bioaccessibility of OTA in a spiked red wine sample under human fasting conditions using an in vitro dynamic digestion model that includes a continuous-flow dialysis system to simulate intestinal passage. To the best of our knowledge, this report is the first examining the bioaccessibility of OTA in wine. A liquid-liquid method was used to extract the OTA and ochratoxin alpha (OTa) from gastrointestinal juices, and the extracts were analysed by HPLC with a fluorescence detector. The bioaccessibility of OTA from the spiked red wine (1.0, 2.0 and 4 μg/l) was high in the gastric compartment (102.8, 128.3 and 122.3%, respectively), whereas in the simulated intestine, it did not exceed 26%, and the amount of OTA that crossed the dialysis membrane was very low (<3.3%). The amount of OTα in gastric chyme ranged from 5.1 to 19.1% of the spiked OTA, whereas in the intestinal compartment it did not exceed 5%. In conclusion, in the in vitro system assayed, OTA exhibited a high bioaccessibility in the simulated stomach, but it decreased after the intestinal digestion and passage through the dialysis membrane.