Influence of Maturation Stages in Different Varieties of Wine Grapes (Vitis vinifera) on the Production of Ochratoxin A and Its Modified Forms by Aspergillus carbonarius and Aspergillus niger

Abstract

Ochratoxin A is the main contaminant mycotoxin of grapes produced mainly by Aspergillus niger and Aspergillus carbonarius. Besides, it is possible that the formation of modified mycotoxin occurs through the plant defense mechanism or also by fungus actions itself. The objective of this study was to evaluate the influence of grape variety and maturation stage on the formation of OTA and modified mycotoxin. The determination of OTA was performed by high-performance liquid chromatography, and a high-resolution mass spectrometry was used for the detection of modified ochratoxin. A positive correlation was observed between the following grapes physicochemical parameters: pH, total soluble solids, total glycosides in glucose, total anthocyanin, and OTA levels produced by A. niger and A. carbonarius. Therefore, the higher the concentrations of these parameters, the greater the production of mycotoxin in grapes. Among the elected targets, we identified the 14-decarboxy-ochratoxin A in Muscat Italia variety at veraison and 15 days after the beginning of veraison stages; and ethylamide-ochratoxin A as a biomarker in the Syrah variety at the ripeness stage.

β-Fructofuranosidase andβ–D-Fructosyltransferase from NewAspergillus carbonariusPC-4 Strain Isolated from Canned Peach Syrup: Effect of Carbon and Nitrogen Sources on Enzyme Production

“…Therefore, the isolated strain was referred to in this work as Aspergillus carbonarius PC-4. A. carbonarius strains have been extensively studied for ochratoxin A production in fruits and beverages [32–34]. Regarding enzyme production, A. carbonarius have been studied for cell plant polysaccharides degradation [35], polygalacturonase and pectinase production [36–38], and also β -Xylosidase [39], among other biotechnological studies.…”

Alimentary Risk of Mycotoxins for Humans and Animals

“…In some cases, they are formed during food processing. The different processing steps influence the levels of mycotoxins present in the final product [60]. Research indicates that some modified mycotoxins can be converted into parent mycotoxins as a consequence of digestive processes in humans and animals, which can lead to adverse health effects.…”

“…Although the toxicological data are scarce, the possibility of converting a modified mycotoxin to its free form can pose a potential health risk, not only to humans but also to animals [2]. Masked mycotoxins are derivatives of mycotoxins that are undetectable by conventional analytical techniques due to the fact that their structures changed in the plant [60]. Conventional methods, for example ELISA, respond to masked forms, while this is unlikely with HPLC-based methods.…”

Ochratoxins in Wines: A Review of Their Occurrence in the Last Decade, Toxicity, and Exposure Risk in Humans

“…According to some research, OTA contamination occurs when grapes are still on the vine, during the ripening period when fungal infections are more active [ 16 , 17 ]. Aspergillus carbonarius, A. ochraceus, A. niger, Penicillium verrucosum, and P. nordicum are the main fungal species responsible for producing this toxin in grapes [ 18 ], with Aspergillus species being more frequent [ 19 ].…”

“…The presence of these modified metabolites in wines could represent three possible scenarios: (1) a decrease in or elimination of toxicity occurs for the primary molecule [ 7 , 8 ]; (2) these compounds could be as toxic or more toxic than the original molecule due to their structural similarities [ 8 , 17 ]; or (3) when ingested in wine, through human metabolism, these molecules can be reconverted into the original toxin [ 95 ]. It should not be ruled out that synergism occurs between modified OTAs and free OTA or other molecules present in this matrix.…”