Physiological and behavioral effects of the mycotoxin deoxynivalenol in Tenebrio molitor larvae

Abstract

Deoxynivalenol (DON) is one of the most prevalent type B trichothecene mycotoxins present in cereals such as: wheat, rye, barley, oats and corn. It initiates a wide range of toxic effects on human and animal health. As an edible insect species for the growing human population, Tenebrio molitor is typically fed on cereal bran or flour. In the present study T. molitor L. larvae were grown for two weeks on wheat bran artificially contaminated with DON at four concentrations: 4.9 μg/g, 8 μg/g, 16 μg/g and 25 μg/g. The effects of DON intake on survival, growth, activity of the antioxidant enzymes - superoxide dismutase (SOD) and catalase (CAT) and the phase II biotransformation enzyme - glutathione-S-transferase (GST), protein content and locomotor activity were monitored in two-month-old T. molitor larvae. The study revealed that DON at concentrations ranging from 4.9 to 25 μg/g wheat bran reduced larval body weight and protein content. Furthermore, it increased SOD and GST activity, had no effect on CAT activity. Also, this study showed that presence of DON in these concentrations has no direct detrimental effects on larval survival, but reduced locomotor activity. The observed effects were particularly pronounced in the larvae given the highest DON concentration 25 μg/g. These finding reveals that DON in artificially contaminated wheat bran at concentrations up to 25 μg/g is able to induce dose-dependent physiological and behavioral changes in T. molitor larvae.