Search Results (346)

Tenebrio molitor is a common stored grains pest. The conventional way for its management involves the use of synthetic fumigants. Despite their effectiveness, these can cause environmental damage. The use of essential oils has emerged as an alternative for its management. Therefore, the aim of this study was to assess Lantana camara essential oil (EO) and endo-borneol biological activities against T. molitor. Insecticidal activity and weight gain were evaluated through the impregnated paper method against larvae and adults, while repellency was conducted with a Y-tube olfactometer; L. camara EO showed higher mortality for T. molitor adults (LC₅₀ = 7.2 μL EO L⁻¹ air) than for larvae (LC₅₀ = 13.7 μL EO L⁻¹ air) after 30 d. Furthermore, L. camara EO was found to be repellent for T. molitor adults (RC₅₀ = 0.08 μL EO cm⁻²). Regarding the EO composition, endo-borneol was identified by GC-MS as a major compound with 14.24% abundance. Larvae exhibited higher susceptibility (LC₅₀ = 7.8 μL L⁻¹ air) to endo-borneol than adults (LC₅₀ = 46 μL L⁻¹ air) after 72 h. Notably, endo-borneol demonstrated significantly higher repellent activity (RC₅₀ = 0.03 μL cm⁻²) than L. camara EO (RC₅₀ = 0.08 μL EO cm⁻²). These findings suggest that endo-borneol has potential as a natural source alternative for T. molitor management. Full article

Competitive industrial farming of Tenebrio molitor L. requires strategies aimed at reducing production costs and improving overall efficiency. Among variable costs, feed is one of the most significant components. Previous research has mainly focused on the nutritional composition of diets, the use of agri-food by-products, and the optimization of multicomponent formulations, sometimes administered in pelleted form during bioassays. However, knowledge about the influence of the administration form is scarce. This study investigated the effects of different feed forms—finely ground (<0.5 mm), coarsely ground (0.5–2 mm), and assembled (pellets, cookies, and crumbles)—on both adult and larval performance. Three feeds (wheat bran, brewer’s spent grain, and chicken feed) were tested to assess adult productivity and larval growth. The results showed non-significant differences in adult survival between feed forms, whereas finely ground feed significantly increased adult productivity and the survival of newborn larvae. Furthermore, larvae in the growing phase (40–60 days old) were able to effectively utilize assembled feeds, with no significant differences in larval weight compared to those reared on ground diets. These findings suggest that pelleted formulations for T. molitor farming should include a fraction of finely ground material to support early larval stages, thereby optimizing survival and development. Moreover, the different influence of feed form provides useful information for planning evaluation trials of multicomponent assembled diets. Full article

Blarina paralytic peptides (BPPs), neurotoxins from shrew saliva that paralyze mealworms, share high sequence similarity with human synenkephalin [1–53] (hSYN), a peptide released from proenkephalin together with opioid peptides that mediate analgesic and antidepressant effects in the brain. Both synthetic BPP2 and hSYN induce a hyperpolarizing shift in the human T-type voltage-gated calcium channel (hCa_v3.2) at sub-micromolar concentrations, although only BPP2 causes paralysis in insects. To gain insight into the functions of these insectivorous animal-specific neurotoxins and the largely uncharacterized brain peptides, we investigated the structure prediction of BPPs and SYNs and their interactions with hCa_v3.2. AlphaFold 3 modeling complemented available cryo-EM data and accurately reproduced the overall channel architecture; however, this inactivated-state model proved unsuitable for predicting agonistic binding of BPPs and SYNs. In contrast, docking simulations using an activated-state hCa_v3.2 homology model revealed distinct ligand-dependent differences in binding energies, affinity, and conformational flexibility. Notably, the C-terminal tail of BPPs—particularly its variable length and flexibility—was identified as a key determinant for the interactions with the S4 voltage-sensing domain of the channel. These findings provide new insights into the evolutionary adaptation of venom peptides in mammals and into potential therapeutic strategies targeting neurological disorders. Full article

This study aimed to assess the effects of partially replacing lean beef with Tenebrio molitor powder at different levels on the physicochemical and microbiological properties of beef patties throughout refrigerated storage. Four treatments were prepared: Control (beef), HT50 (5% T. molitor powder), HT75 (7.5% T. molitor powder), and HT100 (10% T. molitor powder). The inclusion of T. molitor powder significantly increased (p < 0.05) the protein content while reducing cooking loss and diameter reduction (p < 0.05). Color analyses revealed a darker appearance in reformulated patties throughout storage (L* = 36.8–41.2; a* = 6.3–9.3; ΔE* = 4.7–10.4), particularly in HT75 and HT100, compared with control (L* = 43.4–45.5; a* = 10.0–13.7). Kramer shear force values remained comparable (p > 0.05) to the control in HT50 but increased (p < 0.05) in HT75 and HT100 during storage. Lipid oxidation increased (p < 0.05) over time in reformulated treatments; however, initial TBARS values were lower than those of the control. Microbiological analysis showed significantly reduced (p < 0.05) mesophilic and Enterobacteriaceae counts in T. molitor powder formulations. The presence of Bacillus cereus was attributed to T. molitor powder, as no growth was detected in the control. Among reformulated treatments, HT50 proved to be the most suitable beef patty formulation, as it maintained key physicochemical attributes such as color stability, texture, and oxidative stability, while providing nutritional benefits. Full article

The aim of our study was to make one step further to verify a method that can turn back mycotoxin-contaminated crops into the circular economy. Thus, the possibility of utilizing aflatoxin B1 (AfB1)-contaminated corn by yellow mealworms (Tenebrio molitor) was investigated to be used as fish feed components. Four different self-contaminated corn samples were used in our study, of which one was below and three were above the threshold limit (20 µg/kg) regulated by the European Union. The highest applied AfB1 concentration in our study for insect feeding was 415 µg/kg (more than twenty times higher than the threshold). After a five-week feeding period insect mortality was not increased, even in the highly contaminated group, compared to the negative control. The mycotoxin in the dried and ground insects was only detected in the case of feeding with the highest-concentration corn, however it remained as low as 2.2 µg/kg. For studying the possible physiology effects, insect grounds were used in feeding experiments of common carp (Cyprinus carpio) fries. Results showed that insect meal, even if originated from a highly mycotoxin-contaminated crop, did not have a significant effect on the examined fish fries, compared with the control groups. The AfB1 concentrations of the leftover frass after insect rearing were also measured, and in the case of the highest concentration mealworm group, it was 157.6 µg/kg (other groups were under 20 µg/kg). Toxicity of frass extracts from different contaminated groups was also studied using microinjected zebrafish (Danio rerio) embryos. Extracts of the highly contaminated frass samples caused 91.67 ± 3.33% mortality and led to numerous phenotypic changes, which highlights the need for responsible usage of the by-product. However, the effects of injected frass samples, originating from corn with lower and more environmentally relevant AfB1 concentrations, were significantly lower. Full article

Deoxynivalenol (DON) is one of the most common trichothecene mycotoxins found in cereals, posing a significant hazard to food and feed safety. Insects, especially the yellow mealworm (Tenebrio molitor), offer promising alternative protein sources; however, their capacity to metabolise mycotoxins and the nutritional implications are still not fully understood. In this study, T. molitor larvae were reared for two weeks on diets containing DON at 663 or 913 µg/kg, and their biomass was analysed using Liquid Chromatography–Quadrupole Time-of-Flight Mass Spectrometry (LC-QTOF) for DON metabolites and free amino acids, as well as Gas Chromatography–Flame Ionization Detector (GC-FID) for fatty acid profiles. Larvae metabolised DON via multiple pathways, including sulfonation, glucuronidation, sulfation, glucosylation, and de-epoxidation, with a time- and dose-dependent shift towards glucosylation and de-epoxidation. DON exposure significantly reduced the levels of essential amino acids such as methionine, lysine, phenylalanine, and isoleucine, and lowered metabolic intermediates like aspartic and glutamic acid. Conversely, prolonged DON exposure increased linoleic acid levels in larval fat, indicating altered lipid metabolism. These findings demonstrate that T. molitor larvae detoxify DON but incur measurable metabolic costs, leading to changes in amino acid and fatty acid profiles. The dual effect—reduction of toxin levels and nutritional shifts—highlights both the potential and the challenges of using insects for sustainable feed production. Full article

Edible insects, particularly Tenebrio molitor (Linnaeus) (mealworm) and Zophobas morio (Fabricius) (superworm), have drawn increasing attention as alternative protein sources. This study aims to develop an accurate molecular detection method for T. molitor, an EU-approved food species, and to differentiate it from Z. morio, which remains unapproved for human consumption in the EU. The process enables precise and sensitive identification methods by optimizing singleplex and duplex PCR techniques targeting 16S rRNA and COI gene regions. The DNA of T. molitor was detected in various food matrices, including pastries, chocolate, and porridge, while avoiding cross-reactivity with Z. morio, Gryllus asimilis, and Locusta migratoria. The detection limit for both singleplex and duplex PCR was 10 pg of DNA, ensuring robustness against inhibitory effects from complex food matrices. The developed approach ensures reliable detection and compliance with EU regulations regarding insect-based foods, providing a critical tool for food authentication and preventing adulteration. The key advancements of this approach lie in its improved specificity and sensitivity, allowing for the ability to detect complex food matrices. An applied perspective was evaluated using real commercial food products. Full article

Plastic pollution from polyethylene-based materials is a critical environmental concern due to their high persistence. Here, we report the first proof-of-concept application of a multitechnique analytical framework for quantifying linear low-density polyethylene (LLDPE) in Tenebrio molitor frass. Artificially enriched frass–LLDPE mixtures were analyzed using thermogravimetric analysis (TGA), TGA coupled with Fourier-Transform Infrared Spectroscopy (FTIR) and Mass Spectrometry (MS), TGA under inert atmosphere, and solid-state ¹³C nuclear magnetic resonance spectroscopy with Cross-Polarization and Magic Angle Spinning (CP-MAS NMR) ¹³C CP-MAS NMR combined with interval Partial Least Squares (iPLS) modeling. Thermal methods provided insight into decomposition pathways but showed reduced specificity at <1% w/w due to matrix interference. CP-MAS NMR offered matrix-independent quantification, with characteristic signals in the 10–45 ppm region and a calculated LOD and LOQ of 0.173% and 0.525% w/w, respectively. The LOQ lies within the reported ingestion range for T. molitor (0.8–3.2% w/w in frass), confirming biological relevance. This validated workflow establishes CP-MAS NMR as the most robust tool for quantifying polyethylene residues in complex matrices and provides a foundation for in vivo biodegradation studies and environmental monitoring. Full article

Due to their high nutritional value and a lower environmental impact, Tenebrio molitor (T. molitor) larvae are regarded as an alternative protein and lipid source in food industries, animal husbandry, and fishery. This study aimed to investigate the effect of ω-3 PUFA intake on the nutritional value and gut microbiota of T. molitor larvae. Tenebrio molitor (T. molitor) larvae were reared with wheat bran at 20–32 °C for 4 weeks to screen for a suitable temperature. EPA ethyl esters (EE), DHA ethyl esters (ED), DHA triglycerides (TG), and krill oil (KO) were supplemented in wheat bran to rear larvae for 4 weeks, and the compositions including moisture, carbohydrates, crude protein, and crude fats were analyzed. Gut microbiome was analyzed using 16S rRNA amplicon sequencing. Larvae reared on wheat bran showed optimal growth at 28 °C. ω-3 PUFA supplements increased crude protein (1.07–1.16 fold) and crude fat (1.12–1.22 fold) contents without affecting survival. Gut microbiota composition shifted significantly in all ω-3 supplemented groups, altering over 10 genera. Bacteria with changed abundance (e.g., Clostridium), known for roles in protein/lipid metabolism, likely contributed to the enhanced nutritional contents. These findings demonstrate the benefits of ω-3 PUFA supplementation in T. molitor rearing and identify associated gut bacteria. Full article

Background: As edible insects gain importance as sustainable protein sources, their integration into the food system requires that they meet the same safety standards as conventional animal products. This includes systematic testing for residues of pharmacologically active substances, such as antibiotics. To enable such monitoring, validated analytical methods for insect matrices are essential—but currently lacking. This study evaluates whether LC-MS/MS methods already validated for conventional animal products are suitable for detecting antibiotics in edible insects. Methods:Tenebrio molitor larvae were fed wheat flour containing 10 mg of tiamulin or chloramphenicol and 31.3 mg erythromycin per 100 g flour. The antibiotics were mixed into the feed, and their homogeneity and stability were confirmed. After seven days of feeding and a 24-h fasting period, larval samples were analyzed by LC-MS/MS. Results: All three antibiotics were detected in the insects. After seven days, mealworms contained 6.8 ± 0.3 mg/kg tiamulin, 1.4 ± 0.2 mg/kg chloramphenicol, and 224.5 ± 111 mg/kg erythromycin. Following the 24-hour fasting period, concentrations declined markedly to 0.6 ± 0.03 mg/kg, 0.2 ± 0.002 mg/kg, and 130.5 ± 0.7 mg/kg, respectively. Conclusions: The detection of all three antibiotics demonstrates that existing LC-MS/MS methods can be applied to insect matrices. Owing to the small number of replicates and the exploratory nature of the trial, these residue levels should be interpreted qualitatively as a proof of concept. The study provides a reproducible model for further feeding trials and underscores the need for more comprehensive validation. Potential drivers of antibiotic misuse in insect farming are discussed as a basis for developing and expanding testing methods to ensure the food safety of edible insects. Full article

As demand for sustainable protein sources grows, edible insects like Tenebrio molitor (yellow mealworm) are gaining attention as functional feed ingredients. This study investigated how dietary inclusion of T. molitor meal affects gut microbiota composition and diversity in laboratory rats. Wistar rats were divided into three diet groups: standard feed, 35% chicken meal, and 35% T. molitor meal. Fecal samples were collected at weeks 4, 6, and 8. Microbial populations were assessed using culture-based methods, and community structure was analyzed at week 9 via Illumina MiSeq 16S rRNA sequencing. Bioinformatic analyses evaluated microbial diversity and predicted functions. Rats fed T. molitor meal showed significantly reduced counts of total aerobic/anaerobic bacteria, fungi, and coagulase-positive staphylococci. Metagenomics revealed a Firmicutes-dominated microbiota, with enrichment of protein- and cholesterol-metabolizing taxa (e.g., Eubacterium coprostanoligenes, Oscillospiraceae, Ruminococcaceae), and a decline in fiber- and mucin-degrading bacteria like Akkermansia and Muribaculaceae. Functional predictions indicated upregulated amino acid metabolism and chitin degradation. Despite compositional shifts, microbial diversity remained stable, with no signs of dysbiosis. These findings suggest that T. molitor meal supports a safe, functional adaptation of gut microbiota to high-protein, chitin-rich diets, supporting its potential use in monogastric animal nutrition. Full article

Mealworm (Tenebrio molitor, LINNAEUS, 1758) is a protein-rich edible insect. In this study, low-gluten wheat flour was formulated with mealworm protein powder at various concentrations (0%, 5%, 10%, 15%, and 20%) to investigate its influence on the pasting, farinographic, and extensographic properties of low-gluten wheat flour, as well as the changes in the overall quality of the resulting biscuits (soda crackers and cookies). The viscosity of the composite flour decreased with an increasing substitution level of mealworm protein powder, and the setback significantly decreased from 69.31 ± 0.16 RVU (M0) to 19.00 ± 0.71 RVU (M20), indicating enhanced resistance to starch retrogradation. Farinographic and extensographic analyses revealed that the addition of mealworm protein powder reduced dough water absorption, significantly prolonged dough development time and stability time, and enhanced overall dough stability. However, extensibility gradually decreased, with a further reduction observed as the proofing time increased. Concurrently, the baking expansion ratio and hardness of the biscuits decreased. Specifically, for soda crackers, the baking expansion ratio decreased from 198.96 ± 3.88% (M0) to 135.74 ± 1.28% (M20), and hardness dropped from 26.40 ± 1.53 N (M0) to 6.32 ± 0.08 N (M20). For cookies, the baking expansion ratio and hardness decreased from 93.77 ± 0.72% (M0) to 86.06 ± 1.08% (M20) and from 1.76 ± 0.06 N (M0) to 1.10 ± 0.16 N (M20), respectively. The impact of mealworm protein powder (5–20%) was relatively minor in cookies but more pronounced in soda crackers, likely due to differences in formulation and processing methods. Additionally, the crunchiness of soda crackers was 3.42 times greater than that of cookies, whereas resilience was only 0.15 times that of cookies under controlled conditions. Pearson correlation analysis and principal component analysis (PCA) further elucidated the relationships between the dough properties and final product quality. Furthermore, the substitution of mealworm protein powder affected the sensory properties of the product but significantly enhanced its nutritional value, confirming the feasibility of replacing low-gluten wheat flour with mealworm protein powder and offering a theoretical foundation for its development and application in diverse biscuit formulations. Full article

Biopolymers have gained significant attention due to their environmental advantages, with insects emerging as a promising but underutilized source of chitin and chitosan. In this study, chitosan was extracted from the larval exuviae of Tenebrio molitor through sequential demineralization, deproteinization, and deacetylation steps. For selected analyses, the extracted chitosan was further purified via reprecipitation from an acid solution using a basic precipitant (1 M NaOH). Chitosan was then characterized using chemical and instrumental methods. The results indicated that the chitosan had a medium degree of deacetylation (72.27%) and viscosity-average molecular weight (612 kDa), along with minimal ash (0.33%) and amino acid (0.14%) content, suggesting high product quality. FTIR analysis identified characteristic functional groups present, and SEM analysis highlighted a fibrous and porous microstructure in the purified chitosan. The prepared films exhibited favorable properties, including low thickness (0.0197 mm), high swelling degree (335.07%), moderate water solubility (46.99%), and moisture content of 32.39%, supporting their practical applicability. T. molitor exuviae thus represents a sustainable and environmentally friendly source of high-quality chitosan, with beneficial structural and functional properties, supporting its use in a wide array of value-added applications. Full article

Fermentation, a traditional method for enhancing nutritional value and functionality, has significant potential for improving the quality, safety and acceptability of farmed insect products. In this study, yellow mealworm, house cricket and migratory locust were fermented using Lactobacillus plantarum and a commercial starter culture for 48 h. Samples were analyzed for proximate composition, amino and fatty acid profiles, elemental composition and oxidation stability. Fermentation reduced total dietary fiber in yellow mealworm (33%) and house cricket (12%), and increased non-protein nitrogen (38% and 16%), while total and protein nitrogen remained unaffected. Fatty acid profiles also remained unchanged, whereas the amino acid composition varied depending on the species and fermentation culture. Essential mineral concentrations varied depending on species and fermentation culture Fe (19–23%), K (25%), Mg (12–23%), Mn (36–378%), Na (20–49%) and P (22%) increased, levels of Se (15%), and Cu (16%) decreased, while Zn levels showed inconsistent trends among treatments. Oxidation stability of yellow mealworm (41–42%) and migratory locust (21–29%) decreased, but improved for house cricket (153–167%). Overall, fermentation enhanced the nutritional value of edible insects, although the extent of improvement varied by species and fermentation culture. Full article

Deoxynivalenol (DON) is a prevalent mycotoxin in feed, raising concerns about its impact on animal health and feed safety. Insects such as yellow mealworm (Tenebrio molitor) may play a role in the biodegradation of DON-contaminated feed. This study presents the results of a two-week rearing experiment, where 19-week-old yellow mealworm larvae were fed diets with varying concentrations of DON. The larvae were divided into three groups (C, A, and B) that differed in the amount of mycotoxin added to the feed. Larval survival, body mass, and DON accumulation in larvae and their frass were evaluated. A statistical analysis revealed no significant differences in larval survival or body mass gain between the groups. The results point to the low accumulation of DON in larvae, reaching 13.13 ± 2.06 µg/kg (A) and 32.18 ± 4.20 µg/kg (B) after two weeks of feeding. Moreover, at the end of the experiment, DON was detected in larval frass at high concentrations of 507.65 ± 15.31 µg/kg (A) and 862.61 ± 18.53 µg/kg (B), suggesting that larvae are capable of effectively excreting this mycotoxin. The analyzed mycotoxin had no significant effect on larval survival or growth. Deoxynivalenol did not accumulate in the larval biomass and was excreted with frass. These findings enhance our understanding of the interactions between DON and yellow mealworm larvae and have potential implications for using insects in feed production and mycotoxin neutralization within ecosystems. Tenebrio molitor larvae tolerate DON-contaminated feed and effectively excrete the toxin, making them potential candidates for feed detoxification systems. Full article