Effect of an active label based on benzyl isothiocyanate on the morphology and ochratoxins production of Aspergillus ochraceus

- Active labels based on BITC have demonstrated to have antimycotoxigenic activity.
- Active labels caused a decrease on Ochratoxins production, especially on Ochratoxin A.
- Active label modified other secondary metabolites production in A. ochraceus.
- SEM was successfully used to demonstrate the mode of action of BITC on A. ochraceus.
- The active label is an economic and easy approach to improve food safety.

The aim of this work was the study of the main effects of benzyl isothiocyanate (BITC) on A. ochraceus morphology and on its production metabolism of ochratoxins. This compound was evaluated as active agent of an antimicrobial label in food packaging. Microbiological studies showed a slowdown in mould growth when the active material was applied to A. ochraceus and the presence of three different areas of growth. Scanning electron microscopy was successfully used to demonstrate the mode of action of BITC on this strain. A. ochraceus exhibited modifications in morphology compared to the control samples such as the disappearance of sclerotia or cleistothecia An extraction protocol and an analytical method by UPLC-MS/MS to determine ochratoxins (OTs) was developed. The results showed that all these morphological changes were related to a decrease on OTs production, both ochratoxin A (OTA) and ochratoxin B (OTB). The presence of BITC caused a great decrease on OTA that modified the OTA/OTB ratio, increasing the OTB proportion. Furthermore, the active packaging also modified the production of other secondary metabolites. The morphological and metabolic effects observed, as well as the relationship between them, are of great interest since they have not been reported before for A. ochraceus.

161