Interaction of the Emerging Mycotoxins Beauvericin, Cyclopiazonic Acid, and Sterigmatocystin with Human Serum Albumin

Beauvericin (BEA), cyclopiazonic acid (CPA), and sterigmatocystin (STC) are emerging mycotoxins. They appear as contaminants in food and animal feed, leading to economic losses and health risks. Human serum albumin (HSA) forms stable complexes with certain mycotoxins, including ochratoxins, alternariol, citrinin, and zearalenone. HSA binding can influence the toxicokinetics of xenobiotics, and albumin can also be considered and applied as a relatively cheap affinity protein. Therefore, we examined the potential interactions of BEA, CPA, and STC with HSA employing fluorescence spectroscopy, ultracentrifugation, ultrafiltration, and molecular modeling. Spectroscopic and ultracentrifugation studies demonstrated the formation of low-affinity BEA-HSA (K-a approximate to 10(3) L/mol) and moderately strong CPA-HSA and STC-HSA complexes (K-a approximate to 10(4) L/mol). In ultrafiltration experiments, CPA slightly displaced each site marker (warfarin, naproxen, and camptothecin) tested, while BEA and STC did not affect significantly the albumin binding of these drugs. Modeling studies suggest that CPA occupies Sudlow's site I, while STC binds to the Heme site (FA1) on HSA. Considering the interactions of CPA with the site markers, the CPA-HSA interaction may have toxicological importance.

Automated summary

Beauvericin, cyclopiazonic acid, and sterigmatocystin are emerging mycotoxins that can contaminate food and animal feed, resulting in economic losses and health risks. Human serum albumin can form stable complexes with these mycotoxins, influencing their toxicokinetics and potentially serving as a cost-effective affinity protein. This study investigated the interactions of these mycotoxins with human serum albumin using various techniques, revealing the formation of low to moderately strong complexes. The interactions of cyclopiazonic acid with site markers suggest potential toxicological importance.