Valorization of aflatoxin contaminated peanut into biodiesel through non-catalytic transesterification

Abstract

Aflatoxins (AFs) are the extremely hazardous metabolites (carcinogens) that are sporadically observed in crops, and these toxic chemicals are indeed lethal to the health of living organisms including human beings. Thus, AF contaminated food waste needs to be disposed as an environmentally benign way, not releasing it into the environment. This study offered a sustainable disposal and valorization platform for AF contaminated food. Peanut was used as a model food waste, because AF is readily appeared in the peanut during its harvesting, cultivation, storage, transportation process. As the valorization platform, non-catalytic transesterification of AF contaminated peanut was employed to convert it to biodiesel (BD). From the process, lipid in AF contaminated peanut is converted into BD (95.2 wt% yield) at 365 degrees C for 1 min. Since the boiling points of BD and AF are significantly different, this process could also resolve the separation problem of AF (180 degrees C) from BD (> 330 degrees C) during the transesterification reaction. As a comparison study, alkali-catalyzed reaction was done. The alkalicatalyzed one required a pretreatment process to extract peanut oil for transesterification. The highest yield was 67.8 wt% yield after 6 h of reaction at 65 degrees C.