Aflatoxin B Metabolism of Reared in Different Life-Stages

The presence of carcinogenic aflatoxins in food and feed is a major issue. In prior studies, aflatoxin B (AfB) and known primary metabolites were absent from Lesser Mealworm (LMW, ) reared on contaminated diets. LMW is a promising alternative protein source. The objectives of this stu\dy were to determine whether LMW can be reared on AfB-contaminated feed in each life-stage, and to gather more insight into potential metabolites formed. Results suggested no adverse effects in terms of survival/growth when three stages of LMW (larvae, pre-pupae, beetles) were exposed to feed containing AfB concentrations of 200 and 600 µg/kg for 48 h. Insect and frass samples were analyzed by LC-MS/MS and high-resolution MS to, respectively, quantify concentrations of AfB and its major metabolites, and determine secondary metabolites. No AfB or major metabolites were quantified in the insect samples. Mass balance calculations showed that up to 40% of spiked AfB could be recovered in the frass, in the form of AfB, aflatoxicol and AfM. HRMS results suggested the presence of additional metabolites in the frass, but, due to lack of commercially available reference standards for these compounds, exact identification and quantification was not possible. More research is needed to verify the absence of toxicity.