Remoção de ocratoxina A por leveduras

Abstract

Ochratoxin A (OTA) is a toxin highly harmful to human health, produced by fungi of the genus Aspergillus spp. and Penicillium spp. Ochratoxin A contamination in grapes and derived products is frequently reported. Thus, to prevent contamination and detoxify several control methods have been proposed, such as biological, chemical and physical control. The objective of this study was to evaluate the potential removal of ochratoxin A by yeasts isolated from wine. Since the wine industry widely uses sufitos in its process and this chemical additive has an antimicrobial function, the yeasts that obtained the best results in the OTA removal test were submitted to the sodium metabisulfite tolerance test. Two OTA removal tests were performed for 96 hours, with the yeasts MW01, MW06, MW09, PL3, PL8, L1, L2, L3, and L4. Where in the test the only carbon source of the yeasts was OTA. The detection of ochratoxin A in the samples was done by thin layer chromatography (TLC). Only yeast 4 showed potential for OTA removal and proceeded to the sodium metabisulfite resistance test. In the three different concentrations tested of sodium metabisulfite: 0.0225 g/mL, 0.030 g/mL and 0.0375 g/mL, the concentration that had the least impact on cell growth was 0.030 g/L. In this proposed methodology, it was possible to assess that L4 has potential for OTA removal.