Study of some citrus flavanones against zearalenone accumulation by Fusarium graminearum

Abstract

Zearalenone (ZEA) is produced by Fusarium fungi in grains, in particular by Fusarium graminearum. ZEA is a non-steroidal estrogenic mycotoxin widely distributed. The flavanones naringin (NAR), hesperidin (HES) and neohesperidin (NEO) were extracted from citrus industry wastes, such as immature fruits, and tested against ZEA accumulation by F. graminearumin rice. Response Surace Methodology (RSM) was applied in order to optimize flavanones concentrations to achieve total ZEA reduction. Using this methodology, the optimal combinations obtained were HES -NAR: 0.232-0.299, HES-NEO: 0.400-0.001 and NAR-NEO: 0.423-0.001 mmol/kg rice in dry basis. However, NEO seems to have no effect on ZEA inhibition. When it is mixed with other flavanones, they need to be used in higher concentrations than when used alone. These theoretical concentrations obtained by RSM were assayed to verify the results, achieving total inhibition of ZEA accumulation in rice media. The use of the studied flavanones, obtained inexpensively from the residues of citrus industry, would tend to reduce food waste, improve profitability of these industries and diminish ZEA occurrence in rice.