Journal of Stored Products Research 102 (2023) 102113 Available online 28 March 2023 0022-474X/© 2023 Elsevier Ltd. All rights reserved. Changes in antioxidant enzymes and locomotor activity of yellow mealworm larvae fed the mycotoxin zearalenone supplemented diet Milena Jankovi´ c-Tomani´ c a, * , Branka Petkovi´ c b , Jelena Vrankovi´ c c , Vesna Peri´ c-Mataruga a a Institute for Biological Research “Sini ˇ sa Stankovic” – National Institute of the Republic of Serbia, University of Belgrade, Department of Insects Physiology and Biochemistry, Despot Stefan Blvd. 142, 11060, Belgrade, Serbia b Institute for Biological Research “Sini ˇ sa Stankovic” – National Institute of the Republic of Serbia, University of Belgrade, Department of Neurophysiology, Despot Stefan Blvd. 142, 11060, Belgrade, Serbia c Institute for Biological Research “Sini ˇ sa Stankovic” – National Institute of the Republic of Serbia, University of Belgrade, Department of Hydroecology and Water Protection, Despot Stefan Blvd. 142, 11060, Belgrade, Serbia A R T I C L E INFO Handling Editor: Dr Christos Athanassiou Keywords: Mycotoxin Zearalenone Tenebrio molitor larvae Antioxidant enzymes Locomotor activity ABSTRACT The larvae of the yellow mealworm Tenebrio molitor represent a new sustainable source of protein and nutrients for animal and human nutrition. To ensure safe insect-based foods, the risks of mycotoxins and other chemicals must be elucidated. Since oxidative stress is known to underlie many mycotoxin-induced disorders, the present work investigates the effects of the mycotoxin zearalenone (ZEA) on the responses of some oxidative stress biomarkers, superoxide dismutase (SOD), catalase (CAT), and glutathione S-transferase (GST) in the whole body of mealworm, as well as the effects on larval survival, body weight, and locomotor activity, and some aspects of mycotoxin accumulation. Larvae were fed artifcially contaminated wheat bran containing approximately 0.1 mg/kg, 0.5 mg/kg, 2 mg/kg, and 5 mg/kg ZEA for two weeks. The results of the current study showed that ZEA- contaminated wheat bran at a concentration of 0.5 mg/kg was correlated with increased SOD, CAT, and GST enzyme activities and decreased locomotor activity. Higher concentrations of ZEA, i.e., 2 and 5 mg/kg caused enzymes and locomotor activity to return to control levels. The presence of ZEA in the diet for two weeks did not affect survival but resulted in lower weight gain in T. molitor larvae. The concentration of ZEA in the residual material was 21.1–37.6%, while in the larvae it accounted for 0.38–0.51% of the mycotoxin in the feed. The selected concentrations were in accordance with the EU limits for the presence of ZEA in food and with the levels found in naturally contaminated cereals. Our results suggest that ZEA at the tested concentration induces physiological, biochemical, and behavioral changes in larvae that could potentially serve as early markers of mycotoxin contamination. 1. Introduction Mycotoxins are ubiquitous secondary fungal metabolites. They are found in a wide range of crops and foods so contamination of animal feed and human food with mycotoxins is inevitable (Gruber-Dorninger et al., 2019). Zearalenone (ZEA; formerly F2 toxin) is a β-resorcylic acid lactone (Kuiper-Goodman et al., 1987) produced mainly by Fusarium graminearum and F. culmorum (Bennett and Klich, 2003). ZEA contami- nates corn and cereal crops, mainly wheat (D’Mello et al., 1998). In Europe and several transcontinental countries, ZEA has a wide distri- bution, especially in regions with mild and humid climates (Gruber-Dorninger et al., 2019; Ropejko and Twaru´ zek, 2019). Contamination is largely confned to the outer layers of the wheat grain and is thus present in the bran fraction (Edwards, 2011). ZEA is persistent and thermally stable, making it diffcult to eliminate from food chains (Schaarschmidt and Fauhl-Hassek, 2018). Although ZEA has low acute toxicity (Zinedine et al., 2007), long-term exposure at low doses can cause endocrine and metabolic disorders in both animals and humans (Hann et al., 2022). The presence of modifed forms of ZEA in food and feed should also not be underestimated. Tenebrio molitor (L.) is considered a pest of stored grains and grain- based products worldwide (De Souza et al., 2018; Ochoa Sanabria * Corresponding author. Institute for Biological Research “Sini ˇ sa Stankovic” – National Institute of the Republic of Serbia, University of Belgrade, Department of Insect Physiology and Biochemistry, Despot Stefan Blvd. 142, 11060, Belgrade, Serbia. E-mail addresses: miljan@ibiss.bg.ac.rs (M. Jankovi´ c-Tomani´ c), janac@ibiss.bg.ac.rs (B. Petkovi´ c), jeca.s@ibiss.bg.ac.rs (J. Vrankovi´ c), vesper@ibiss.bg.ac.rs (V. Peri´ c-Mataruga). Contents lists available at ScienceDirect Journal of Stored Products Research journal homepage: www.elsevier.com/locate/jspr https://doi.org/10.1016/j.jspr.2023.102113 Received 10 January 2023; Received in revised form 21 March 2023; Accepted 21 March 2023