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The phenolic extracts obtained from rice bran cultivated with Rhizopus oryzae were evaluated about their abitily to inhibit the production of trichotecenes and emerging mycotoxins by Fusarium strains on sweet corn cobs (Zea mays L.). The rice bran was cultured with R. oryzae for 48 h at 30 °C. The phenolic compounds were extracted, clarified, lyophilized and ressuspend as water solution with different concentrations. The phenolic acid extracts were applied on sweet corn inoculated by F. cerealis, F. graminearum and F. poae incubated by 15 days at 25 °C and afterward the fermented corn was autoclaved and frozen. The mycotoxins were quantified by LC-MS/MS. The mycotoxin production by all Fusarium strains evaluated was reduced in relation to the control. F. poae was the most sensitive, because its production of the toxins T-2 and HT-2 and BEA was inhibited by phenolic extract 0,5% (p/v), while extract 1% (p/v) inhibited 96% of the DON production. DON, 3ADON and 15ADON production by F. graminearum and F. cerealis was also reduced. Therefore, the extract is a promising antimicotoxinogenic against Fusarium toxins production on sweet corn cobs and should be a good alternative to reuse wastes from agroindustry.

In this study the antifungal potential of a phenolic extract obtained from rice bran fermented with Rhizopus oryzae CECT 7560 and its application in the elaboration of bread was assessed.; Results: Eighteen compounds with antifungal potential were identified by LC-ESI-qTOF-MS in the extract: organic acids, gallates and gallotannins, flavonoids, ellagic acid and benzophenone derivatives. The extract was active against strains of Fusarium, Aspergillus and Penicillium, with minimum inhibitory concentration ranging from 390 to 3100 µg mL-1 and minimum fungicidal concentration variable from 780 to 6300 µg mL-1 . The strains that were most sensitive to the phenolic extract were F. graminearum, F. culmorum, F. poae, P. roqueforti, P. expansum and A. niger. The phenolic extract added at 5 and 1 g kg-1 concentrations in the preparation of bread loaves contaminated with P. expansum produced a reduction of 0.6 and 0.7 log CFU g-1 . The bread loaves treated with calcium propionate and 10 g kg-1 of the phenolic extract evidenced an improvement in their shelf lives of 3 days.; Conclusion: The phenolic extract assessed in this study could be considered as an alternative for inhibiting toxigenic fungi and as a substitute for synthetic compounds in food preservation. © 2018 Society of Chemical Industry.; © 2018 Society of Chemical Industry.