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In broiler production, numerous feed additives have been utilized to promote growth, feed efficiency, immunity, and antioxidant capacity. Similarly, various techniques, including electric fans, cooling pad systems, and water sprinkling through foggers, have been employed to mitigate heat stress in poultry. However, due to cost constraints, these methods may not always be feasible, and alternative nutritional strategies can be followed, including the use of balancing of nutrients. One such nutritional strategy for reducing stress is the incorporation of Tenebrio molitor (mealworm) as a feed additive. Therefore, this study was designed to investigate the impact of T. molitor as a feed supplement on the performance, immunity, and economics of heat-stressed broilers. A total of 150 (day-old) broilers were randomly allocated to five dietary groups: such as D0 (control), D1, D2, D3, and D4, provided with T. molitor at the rate of 0, 0.5, 1.0, 1.5, and 2 g/kg of feed, respectively. The broilers were exposed to temperatures ranging from 32-38°C during the trial. Results showed the highest significant total weight gain, improved feed conversion ratio, and dressing percentage, and reduced feed intake in the D4 group compared to all other groups. Similarly, the highest antibody titers against the Newcastle disease, and lower mortality rate were calculated in the D4 group than in the remaining groups. Meat quality was not affected. A significant increase in the net profit was observed in the D4 group as compared to the leftover groups. Based on the current findings, it is concluded that T. molitor at the rate of 2.0 g/kg in broiler feed improves the production performance, boosts the immune response against the Newcastle disease, and increases the economic return. [ABSTRACT FROM AUTHOR]

Simple Summary: Research on alternative protein sources is becoming increasingly important in our modern world due to the issue of sustainability and efficiency in food production. Insects are seen as promising alternatives to known animal protein sources due to their attractive nutritional composition and the fact that they can be bred and fattened in a possibly more resource-efficient way. As consumers, especially in Europe, have a certain disgusting feeling towards whole insects (larvae), various research projects are working on the production of hybrid (meat) products in which the insects are mostly processed as dried powders or flour so that they are unrecognizable to the consumer as a whole. In this study, in order to avoid the high-energy and complex steps of pre-processing, such as protein or fat extraction, drying, or hydrolysis, whole larvae of the species Alphitobius (A.) diaperinus (Alphitobius diaperinus, Panzer, 1797) and Tenebrio (T.) molitor (Tenebrio molitor, Linnaeus, 1758) were pulverized and then processed in a meat grinder (without pre-processing) together with the lean meat and other required ingredients. Five batches of two types of cooked sausages (turkey and pork cooked sausages) were produced: in addition to a control sausage without insect content, 10% and 20% of the turkey and pork lean meats were replaced with A. diaperinus and/or T. molitor larvae powder. The replacement with insect larvae had an influence on the color of the sausages, as well as on sensory properties such as smell and appearance. There was no effect on texture and nutritional values (e.g., fat and protein content). The processing of the insect larvae in the meat product also had no effect on the growth of inoculated bacterial species over a storage period. Proteins from insect production represent an interesting (environmentally friendly) option or supplement to commercial livestock farming. At present, however, the larval stages of T. molitor (mealworm) and A. diaperinus (buffalo worm) have been authorized as food for human consumption EU-wide, as have the nymph and adult stages of Locusta (L.) migratoria (Locusta migratoria, Linnaeus, 1758) and Acheta (A.) domesticus (house cricket, Acheta domesticus, Linnaeus, 1758). However, there is the problem that insects that are recognizable as a whole tend to be avoided by consumers, especially in the European region, as they are reminiscent of living things and can cause aversion and disgust in consumers. Against this background, in the present study, five batches of two types of cooked sausages were produced: on the one hand, with turkey, and on the other hand, with pork lean meat as a base. In different formulations, 10% and 20% of the meat contents (turkey or pork) in these meat products were replaced by deep-frozen, pulverized T. molitor and A. diaperinus larvae. The effects of the addition of these insects in the products on the microbiological and physicochemical parameters of these cooked sausages, compared to a product without insect content, directly after heating, were investigated. After production, a storage trial was also carried out to determine whether possible insect ingredients could influence the growth of inoculated bacterial species (Bacillus (B.) cereus, Escherichia (E.) coli, Listeria (L.) monocytogenes, and Campylobacter (C.) jejuni) and how the addition of insect larvae affectsthe sensory and physicochemical properties during storage. The study showed that the products with insects had reduced lightness (turkey p C = 0.025), increased yellowness (pork p S = 0.0009, p C < 0.0001 and turkey p C = 0.0027) and a reduced red color (pork p S < 0.0001, p C = 0.0001) after heating when compared to the cooked sausages without insects. However, no significant differences between the various cooked sausages with or without insects in terms of cooking loss, firmness, and protein, ash, and fat or water contents were found. The microbiological tests showed, on the one hand, that the prior microbial reduction (e.g., in the form of blanching) of the insect larvae was essential in order to guarantee the flawless microbiological quality of the cooked sausages and, on the other hand, that the addition of insects to the cooked sausages did not significantly affect the growth of the inoculated bacterial species and that no sensory differences could be detected during storage. Despite the significant color effects on the product, A. diaperinus and T. molitor larvae would be suitable as protein or meat alternatives in cooked sausages, but they would have to undergo pre-treatment, primarily with regard to microbiological safety. The extent to which a complete replacement of meat is possible has to be investigated in further studies. [ABSTRACT FROM AUTHOR]

Abstract Tenebrio molitor, which is rich in various nutrients, and its polysaccharides, as significant bioactive substances, exhibit strong antioxidant effects. This study utilized defatted T. molitor as raw material and employed an ultrasound-assisted extraction method. The factors considered include extraction temperature, time, ultrasound power, and liquid-to-feed ratio, with the yield of T. molitor polysaccharides as the response value. Based on single-factor experiments and response surface methodology, the optimal extraction parameters for T. molitor polysaccharides were determined. Following purification, protein removal, and dialysis to eliminate impurities, the structure of the extracted polysaccharides was preliminarily investigated using infrared spectroscopy. Their antioxidant activities were explored by measuring their DPPH·, OH·, and ABTS+· radical scavenging abilities and Fe3+ reducing power. The results indicated that the optimal conditions for ultrasound-assisted extraction were an extraction temperature of 75 °C, an extraction time of 150 min, an ultrasound power of 270 W, and a liquid-to-feed ratio of 15:1 mL/g, yielding a polysaccharide extraction rate of 9.513%. Infrared spectroscopy analysis revealed the presence of pyranose sugars with main functional groups including C-O, C=O, and O-H. Antioxidant activity tests showed that within a certain concentration range, the higher the polysaccharide concentration, the stronger its radical scavenging abilities. Compared with Vitamin C(Vc), the polysaccharides had stronger scavenging abilities for DPPH· and OH·, some scavenging ability for ABTS+·, and Fe3+ reduction ability, and corresponding to IC50 values of 0.9625, 9.1909, and 235.69 mg/mL respectively. The Fe3+ reducing power reached a maximum absorbance of 0.38899 at a concentration of 1.6 mg/mL. T. molitor polysaccharides demonstrate promising antioxidant activity and potential as functional ingredients in food, health products, and pharmaceuticals, providing new technical references for the development and utilization of T. molitor resources.

The objective of this study was to explore the impacts of various ultrasonic powers (0, 300, 500, 700, and 900 W) on the structure and functional attributes of the myofibrillar protein (MP) of Tenebrio molitor. As the ultrasonic intensity escalated, the extraction efficiency and yield of the MP rose, while the particle size and turbidity decreased correspondingly. The reduction in sulfhydryl group content and the increase in carbonyl group content both suggested that ultrasonic treatment promoted the oxidation of the MP to a certain extent, which was conducive to the formation of a denser and more stable gel network structure. This was also affirmed by SEM images. Additionally, the findings of intrinsic fluorescence and FTIR indicated that high-intensity ultrasound significantly altered the secondary structure of the protein. The unfolding of the MP exposed more amino acid residues, the α-helix decreased, and the β-helix improved, thereby resulting in a looser and more flexible conformation. Along with the structural alteration, the surface hydrophobicity and emulsification properties were also significantly enhanced. Besides that, SDS–PAGE demonstrated that the MP of T. molitor was primarily composed of myosin heavy chain (MHC), actin, myosin light chain (MLC), paramyosin, and tropomyosin. The aforementioned results confirmed that ultrasonic treatment could, to a certain extent, enhance the structure and function of mealworm MP, thereby providing a theoretical reference for the utilization of edible insect proteins in the future, deep-processing proteins produced by T. molitor, and the development of new technologies. [ABSTRACT FROM AUTHOR]

The objective of this study was to explore the impacts of various ultrasonic powers (0, 300, 500, 700, and 900 W) on the structure and functional attributes of the myofibrillar protein (MP) of Tenebrio molitor. As the ultrasonic intensity escalated, the extraction efficiency and yield of the MP rose, while the particle size and turbidity decreased correspondingly. The reduction in sulfhydryl group content and the increase in carbonyl group content both suggested that ultrasonic treatment promoted the oxidation of the MP to a certain extent, which was conducive to the formation of a denser and more stable gel network structure. This was also affirmed by SEM images. Additionally, the findings of intrinsic fluorescence and FTIR indicated that high-intensity ultrasound significantly altered the secondary structure of the protein. The unfolding of the MP exposed more amino acid residues, the α-helix decreased, and the β-helix improved, thereby resulting in a looser and more flexible conformation. Along with the structural alteration, the surface hydrophobicity and emulsification properties were also significantly enhanced. Besides that, SDS–PAGE demonstrated that the MP of T. molitor was primarily composed of myosin heavy chain (MHC), actin, myosin light chain (MLC), paramyosin, and tropomyosin. The aforementioned results confirmed that ultrasonic treatment could, to a certain extent, enhance the structure and function of mealworm MP, thereby providing a theoretical reference for the utilization of edible insect proteins in the future, deep-processing proteins produced by T. molitor, and the development of new technologies.

In recent years, insect meal has attracted increasing interest as an innovative protein source to replace fish meal in feed formulations due to its valuable nutritional profile. This research aimed to compare the effects of different levels of dietary inclusion of the yellow mealworm beetle (T. molitor) larvae meal on the sensory quality of rainbow trout (Oncorhynchus mykiss) fillets and retrospectively on the acceptability of this protein source to consumers. The results showed that the inclusion of T. molitor larvae meal did not induce sensory changes in the trout fillets, while regarding consumer acceptability and willingness to buy and pay, it was shown that a certain level of rejection towards this alternative protein still exists. The work described in this scientific manuscript adds more knowledge on the study of consumer acceptability of this protein source. [ABSTRACT FROM AUTHOR]

In the study of fungal pathogenesis, alternative methods have gained prominence due to recent global legislation restricting the use of mammalian animals in research. The principle of the 3 Rs (replacement, reduction, and refinement) is integrated into regulations and guidelines governing animal experimentation in nearly all countries. This principle advocates substituting vertebrate animals with other invertebrate organisms, embryos, microorganisms, or cell cultures. This review addresses host–fungus interactions by employing three-dimensional (3D) cultures, which offer more faithful replication of the in vivo environment, and by utilizing alternative animal models to replace traditional mammals. Among these alternative models, species like Caenorhabditis elegans and Danio rerio share approximately 75% of their genes with humans. Furthermore, models such as Galleria mellonella and Tenebrio molitor demonstrate similarities in their innate immune systems as well as anatomical and physiological barriers, resembling those found in mammalian organisms. [ABSTRACT FROM AUTHOR]

Larva dari Tenebrio molitor belum dimanfaatkan secara maksimal, sementara secara alami memiliki manfaat sebagai pengurai senyawa organik dan anorganik di ekosistem. Penelitian ini bertujuan untuk menghitung rerata pertambahan panjang dan bobot, laju degradasi,dan nilai indeks reduksi (WRI) beberapa jernis paper pulp menggunakan larva T. molitor. Penelitian menggunakan Rancangan Acak Lengkap (RAL) dengan 10 larva T. molitor instar 8. Pakan yang diberikan terdiri dari tisu makan, tisu basah, dan puntung rokok. Larva kontrol diberi pakan dedak. Masing-masing pakan diberikan sebanyak 1 gram dan diulang lima kali. Larva diukur pertambahan panjang dan beratnya 3 hari sekali. Pergantian pakan dilakukan dalam 3 hari, apabila sebelum 3 hari pakan yang diberikan habis, maka larva diberi pakan sebanyak 1 gram. Analisis data yang digunakan pada penelitian ini adalah analisis inferensial dengan taraf kepercayaan 5%. Nilai tertinggi pertambahan panjang didapatkan pada pakan tisu basah dan putung rokok sebesar 1.58 gr sedangkan terendah pakan tisu makan sebesar 1.41 gr. Nilai tertinggi pertambahan bobot larva pada pakan tisu basah (0.06 gr), sedangkan terendah pakan tisu makan dan putung rokok (0.05 gr). Nilai tertinggi laju degradasi pada pakan tisu makan (0.88), sedangkan terendah pada pakan tisu basah (0.45). Nilai tertinggi WRI pada pakan putung rokok (0.49), sedangakn terendah pada pakan tisu makan (0.23). Kesimpulan dari penelitian ini bahwasanya penggunaan larva T. molitor bisa mendegradasi berbagai olahan paper pulp.

In recent years, insect meal has attracted increasing interest as an innovative protein source to replace fish meal in feed formulations due to its valuable nutritional profile. This research aimed to compare the effects of different levels of dietary inclusion of the yellow mealworm beetle (T. molitor) larvae meal on the sensory quality of rainbow trout (Oncorhynchus mykiss) fillets and retrospectively on the acceptability of this protein source to consumers. The results showed that the inclusion of T. molitor larvae meal did not induce sensory changes in the trout fillets, while regarding consumer acceptability and willingness to buy and pay, it was shown that a certain level of rejection towards this alternative protein still exists. The work described in this scientific manuscript adds more knowledge on the study of consumer acceptability of this protein source.

Previous studies have shown that larvae of the yellow mealworm, Tenebrio molitor L. (Coleoptera: Tenebrionidae), need a source of moisture to grow and perform well. Currently, much research has been oriented towards the effect of dry feed on larval growth and performance. The effect of different wet feeds as moisture source on the performance traits of T. molitor larvae has not been thoroughly investigated yet. This study aims to investigate in laboratory trials the effect of various gelling agents (agar, carrageenans, guar gum, xanthan gum, sodium alginate, modified starch, and pectin) on the growth and performance of T. molitor larvae. A number of 50 newly emerged larvae obtained from the rearings of the LEAZ were inserted in plastic vials together with 4 g of wheat bran as dry feed. Additionally, 1 g of gelling agents was provided 3 times per week as moisture sources. Carrot slices served as control. Larval survival and weight were recorded weekly until the appearance of the first pupa. Dry feed was replenished when depleted. Our data showed that gelling agents efficiently supported the growth of T. molitor larvae, in terms of larval survival and weight, as well as feed utilization expressed as FCR. Interestingly, carrageenans seem to be the most appropriate gelling agent for T. molitor larvae rearing as it can enhance their weight and is also able to reduce their development time and their specific growth rate. [Display omitted] • Gelling agents were used as a moisture source for the rearing of T. molitor larvae. • Gelling agents were a suitable moisture source that did not impact larvae growth. • Carrot slices were the most suitable moisture source. • Carrageenan reduced development time of the larvae. [ABSTRACT FROM AUTHOR]

This paper presents the effect of insecticides on the composition of the surface compounds of one of the most harmful insects, Tenebrio molitor, by analysis using GC–MS. As a result of the use of insecticides, the composition of the chemical compounds on the surface of insects changes, depending on the insecticides used. The most numerous groups of the marked compounds were fatty acids, alkanes, esters and sterols. The content of the identified compounds in the larvae increased at both 24 and 48 h after the application of insecticides, in comparison with the control samples. The content of identified compounds in the samples taken from the females increased 24, 48 and 72 h after the application of insecticides in comparison with the control samples. By contrast, in samples prepared from males, the content of identified compounds decreased 24 h after the application of insecticides, compared with the control samples. The highest content of chemical compounds was for fatty acids and alkanes after the use of insecticides. The content of fatty acids after the application of the insecticide with deltamethrin was 62.1 ± 3.3–466.9 ± 5.9 μg/g, and after the application of the insecticide with cyfluthrin was 49.9 ± 1.9–458.3 ± 4.2 μg/g. However, the content of alkanes after the use of deltamethrin was 115.6 ± 4.2–4672.0 ± 32.1 μg/g, and after the use of cyfluthrin was 189.4 ± 3.8–3975.0 ± 10.2 μg/g. [ABSTRACT FROM AUTHOR]

Abstract In the case of Tenebrionidae family insects, studies focus on larval stage, leaving a lack of information regarding other stages. Therefore, this study was performed in order to understand the differences between the nutritional composition and the bioactivity of two species of this family in their adult stage, fed with a specific diet. Adult beetles of both species were defatted, lyophilized and protein extracted with buffer. Proximal and phytochemical analysis of the extracts of each insect were performed, along with protein extract and hydrolysis analysis by Tris-Tricine and Tris Glycine SDS PAGE. This analysis showed that T. molitor contained more protein and fat than U. dermestoides but contained less crude fiber. The protein extraction was made with PBS, where 130 and 45 kDa bands showed predominant for U. dermestoides, and less protein was present for T. molitor. Antioxidant and antimicrobial activities of the enzymatic protein hydrolysates and protein crude extracts were determined. Presence of protein associated with the antioxidant activity were found in both insects. Nonetheless U. dermestoides had a higher antioxidant activity with the protein extract in contrast with the higher antioxidant activity shown by U. dermestoides once the extracts were digested. After proteolysis, protein extracts showed an increasing antioxidant activity, plus, the ability to inhibit microbial growth of Proteus, Shigella and Bacillus. Insect protein hydrolysates with protease open the possibility for the use of these beetles as new sources of encrypted peptides for microbiological control once characterized.

Innate immunity is the ultimate line of defense against invading pathogens in insects. Unlike in the mammalian model, in the insect model, invading pathogens are recognized by extracellular receptors, which activate the Toll signaling pathway through an extracellular serine protease cascade. In the Toll-NF-κB pathway, the extracellular spätzle protein acts as a downstream ligand for Toll receptors in insects. In this study, we identified a novel Spätzle isoform (Tm Spz1b) from RNA sequencing database of Tenebrio molitor. Tm Spz1b was bioinformatically analyzed, and functionally characterized for the antimicrobial function by RNA interference (RNAi). The 702 bp open reading frame of Tm Spz1b encoded a putative protein of 233 amino acid residues. A conserved cystine-knot domain with seven cysteine residues in Tm Spz1b was involved in three disulfide bridges and the formation of a spätzle dimer. TmSpz1b was mostly expressed in the hemocytes of T. molitor late instar larvae. The mRNA expression of TmSpz1b was highly induced in the hemocytes after Escherichia coli , Staphylococcus aureus , and Candida albicans stimulation of T. molitor larvae. TmSpz1b silenced larvae were significantly more susceptible to E. coli infection. In addition, RNAi-based functional assay characterized Tm Spz1b to be involved in the positive regulation of antimicrobial peptide genes in hemocytes and fat bodies. Further, the TmDorX2 transcripts were downregulated in TmSpz1b silenced individuals upon E. coli challenge suggesting the relationship to Toll signaling pathway. These results indicate that Tm Spz1b is involved in the T. molitor innate immunity, causes the sequestration of Gram-negative bacteria by the regulatory action of antimicrobial peptides, and enhances the survival of T. molitor larvae. [ABSTRACT FROM AUTHOR]

Purpose: Global food production needs to increase to provide enough food for over 9 billion people living by 2050. Traditional animal production is among the leading causes for climate change and occupation of land. Edible insects might be a sustainable protein supply to humans, but environmental life cycle assessment (LCA) studies on them are scarce. This study performs an LCA of a small-scale production system of yellow mealworms (Tenebrio molitor) in Central Europe that are supplied with organic feedstuff. Methods: A combined ReCiPe midpoint (H) and CED method is used to estimate the potential environmental impacts from cradle-to-gate. Impact categories include global warming potential (GWP), non-renewable energy use (NREU), agricultural land occupation (ALOP), terrestrial acidification potential (TAP) and freshwater eutrophication potential (FEP). The robustness of the results is tested via sensitivity analyses and Monte Carlo simulations. Results and discussion: Impacts related to the production of 1 kg of edible mealworm protein amount to 20.4 kg CO2-eq (GWP), 213.66 MJ-eq (NREU), 22.38 m2 (ALOP), 159.52 g SO2-eq (TAP) and 12.41 g P-eq (FEP). Upstream feed production and on-farm energy demand related to the heating of the facilities are identified as environmental hot-spots: Depending on the impact category, feed supply contributes up to 90% and on-farm heating accounts for up to 65% of overall impacts. The organic mealworm production system is contrasted with a selected Austrian organic broiler production system, to which it compares favourably (18–72% lower impacts per category), with the exception of freshwater eutrophication (6% higher impacts). Conclusions: This case study shows that the Austrian mealworm production system compares favourably to traditional livestock systems. Compared to LCAs from large-scale T. molitor rearing facilities in France and in the Netherlands, however, the Austrian production system cannot compete for the reasons of production scale, feed conversion efficiency and type of production system. Nevertheless, the investigated mealworms represent a sustainable protein alternative that should be added to the Western diet. [ABSTRACT FROM AUTHOR]

Innate immunity is the ultimate line of defense against invading pathogens in insects. Unlike in the mammalian model, in the insect model, invading pathogens are recognized by extracellular receptors, which activate the Toll signaling pathway through an extracellular serine protease cascade. In the Toll-NF-κB pathway, the extracellular spätzle protein acts as a downstream ligand for Toll receptors in insects. In this study, we identified a novel Spätzle isoform (TmSpz1b) from RNA sequencing database of Tenebrio molitor. TmSpz1b was bioinformatically analyzed, and functionally characterized for the antimicrobial function by RNA interference (RNAi). The 702 bp open reading frame of TmSpz1b encoded a putative protein of 233 amino acid residues. A conserved cystine-knot domain with seven cysteine residues in TmSpz1b was involved in three disulfide bridges and the formation of a spätzle dimer. TmSpz1b was mostly expressed in the hemocytes of T. molitor late instar larvae. The mRNA expression of TmSpz1b was highly induced in the hemocytes after Escherichia coli, Staphylococcus aureus, and Candida albicans stimulation of T. molitor larvae. TmSpz1b silenced larvae were significantly more susceptible to E. coli infection. In addition, RNAi-based functional assay characterized TmSpz1b to be involved in the positive regulation of antimicrobial peptide genes in hemocytes and fat bodies. Further, the TmDorX2 transcripts were downregulated in TmSpz1b silenced individuals upon E. coli challenge suggesting the relationship to Toll signaling pathway. These results indicate that TmSpz1b is involved in the T. molitor innate immunity, causes the sequestration of Gram-negative bacteria by the regulatory action of antimicrobial peptides, and enhances the survival of T. molitor larvae.

Being rich in nutrients insects are potential nutraceutical resources. In the present study, we have selected the 8th instar larval stages of Tenebrio molitor and 5th instar nymphal stages of Sphenarium purpurascens, because these are the most sought after stages in the edible insect market in various states of the Mexican Republic. We have estimated their proximate composition and mineral contents and compared them with red meat and white meat. S. purpurascens has been found to be rich in protein and energy, whereas T. molitor contains maximum amount of fat and energy that are even better than that of red and white meat. Both of them also contain higher amount of minerals compared to red and white meat. It has been further observed that only 500g of insect flour can provide almost all the minerals in question, whereas the same amount of red and white meat can provide merely three of them. Thus, insects should be exploited as a source of nutraceuticals, more in depth study is necessary in this aspect though. [ABSTRACT FROM AUTHOR]

Defensins are a major family of antimicrobial peptides that serve as the innate immune defense of both vertebrates and invertebrates. Due to their antimicrobial, chemotactic, and regulatory activities, Defensins have been exploited for their therapeutic potential. Insect Defensins are cysteine‐rich and contain an N‐terminal loop, α‐helix, and antiparallel β‐sheet, forming a "cysteine‐stabilized alpha beta (CSαβ)" or "loop–helix‐sheet" structure. In this study, we identified the full‐length open reading frame (ORF) sequences of Defensin (TmDef) and Defensin‐like (TmDef‐like) genes from the mealworm beetle Tenebrio molitor using in silico methods. TmDef and TmDef‐like genes encode the peptides of 72 and 71 amino acid residues, respectively. TmDefensin is comprised of a Defensin domain and the TmDefensin‐like is comprised of a signal peptide of 21 amino acid residues. Phylogenetic analysis revealed close similarities of TmDefensin with the Defensin of Acalolepta luxuriosa of the longhorn beetle family. The expression of TmDef mRNA was found to be greater than that of TmDef‐like mRNA and was mostly expressed in the pupal and adult stages. Tissue distribution showed high expression of TmDef‐like mRNA in larval hemocytes, gut, integument, and fat body, while in adults, the expression was high in gut and hemocytes. Following bacterial and fungal stimulation in vivo, TmDef was upregulated at 24 h post‐infection in whole body, fat body, and hemocytes of the larvae. Even TmDef‐like mRNA was upregulated in the gut and hemocytes at 12 and 9 h post‐infection respectively. These results suggest that TmDef and TmDef‐like genes play important roles in protecting T. molitor from microbial contact. [ABSTRACT FROM AUTHOR]

Sulfakinins (SKs) are pleiotropic neuropeptides commonly found in insects, structurally and functionally homologous to the mammalian gastrin/cholecystokinin (CCK) neuropeptides. SKs together with sulfakinin receptors (SKRs) are involved in sulfakinin signaling responsible for variety of biological functions, including food intake or fatty acid metabolism. In the present study, we determined the distribution of SKRs in Tenebrio molitor larvae and characterized the impact of nonsulfated and sulfated SKs on carbohydrates and insulin-like peptides (ILPs) level in beetle hemolymph. Our results indicate the presence of both sulfakinin receptors, SKR1 and SKR2, in the nervous system of T. molitor. The distribution of SKR2 in peripheral tissues was more widespread than SKR1, and their transcripts have been found in fat body, gut and hemolymph. This is also the first evidence for SKRs presence in insect hemocytes indicating immunotropic activity of SKs. Moreover, in the present study, we have demonstrated that SKs regulate ILPs and carbohydrates level in insect hemolymph, and that sulfation is not crucial for peptides activity. Our study confirms the role of SKs in maintaining energy homeostasis in beetles. [ABSTRACT FROM AUTHOR]

The industrial farming of edible insects for food and feed generally employs cultivated plants and derivatives as rearing diets. These feed substrates may contain toxins produced by different species of fungi which cause adverse health effects to consumers. Frequently found in cereals and cereal products, mycotoxins aflatoxins, ochratoxins and fumonisins are harmful to human and animal health. In this study the uptake of aflatoxin B1 (AFB1), ochratoxin A (OTA) and fumonisin B1 (FB1) and their elimination rates were investigated in T. molitor larvae fed on cereal-based diets contaminated with two concentration levels for each mycotoxin. New analytical methods for extraction and quantification of AFB1, OTA and FB1 residues in larvae were developed and validated. It has been demonstrated that T. molitor larvae did not accumulate in detectable or dangerous concentrations the three tested mycotoxins at the two tested concentration levels and that a fasting period of 24 hours ensured a sufficient elimination rate of AFB1, OTA and FB1 residues. These results represent a preliminary investigation to define an appropriate quality control procedure to assess the safe use of T. molitor for food and feed purposes. [ABSTRACT FROM AUTHOR]

Developing good microbial pesticides depends on isolating and knowing their pathogenicity. For this purpose, entomopathogenic Metarhizium anisopliae fungi were isolated from soils in Erzincan province and galleria bait method was used. Molecular identification of the isolates was performed by using ITS rDNA analysis. As a test organism, Galleria mellonella and Tenebrio molitor larvae were used and suspensions of 2x107 conidia ml-1 were prepared adding Tween 80®. Bioassays were performed by dipping technique and mortality was recorded daily for 12 days. Each assay consisted of 3 replicates with 10 insects larvae. Ten fungal isolates were obtained from the bait method. Based on classical and molecular methods, all fungal isolates were identified as M. anisopliae and deposited into GenBank database with MH104853 - MH104862 accession numbers. All isolates of M. anisopliae were pathogenic to G. mellonella and T. molitor with a mortality rate of 63.3±3.3% - 83.3±3.3% and 30±5.8% - 66.7±3.3%, respectively 12 days after application. As a result, MaEMR1a and MaEO3 isolates can be applied as good biological control agents for pest insects. [ABSTRACT FROM AUTHOR]

Feeding especially those of protein sources is the main input in the total cost-price of poultry production. This fact is also valid for meat type quail populations which are subjected to the genetic breeding program. It is a subject of research that T. molitor can be a good alternative protein source. This research elucidated the effects of 10% T. molitor addition as protein resource to quail diet on weight gains, feed intake and feed consumptions on weekly basis by comparing with control (soybean meal as main protein resource in diet). In addition, genetic parameters were estimated for weight gain and feed conversion rate characteristics. Total of 294 Japanese quails obtained from 50 full-sib families were used in this study. The overall mean weight gain was 27.7, 44.7, 60.7, 54.9 and 39.3 g at 1, 2, 3, 4 and 5 weeks of age, respectively. The overall average feed intake in the end of 1, 2, 3, 4 and 5 weeks were 50.5, 109.7, 112.0, 138.7 and 198.7 g per week, respectively, whereas the feed conversion rates for respective growth periods were 1.90, 2.52, 1.90, 2.59 and 6.04. T. molitor added 10% to the ration, resulted in a lower weight gain in the first three weeks of experiment comparing to the control group. However, this event does not apply to the later stages of growth period. The T. molitor addition into the ration led to a decrease in feed consumption after 3 weeks of age without any loss of growth performance. In this case, the feed conversion rates of birds at 4 and 5 weeks of age were lower for the T. molitor group. The heritability estimates for weight gain at 1, 2, 3, 4 and 5 weeks were 0.78, 0.55, 0.74, 0.53 and 0.21 respectively whereas those of the feed conversion rates were 0.64, 0.50, 0.69, 0.43 and 0.06. Instead of soybean meal in meat type quail diets, as an alternative dietary protein source, use of 10% T. molitor was found to have negligible effects on genetic parameter estimates for weight gain and feed conversion rate traits. [ABSTRACT FROM AUTHOR]

The discovery that insect larvae can feed on kinds of foam plastics opened new avenues and provided a potential solution for plastic wastes biodegradation. This study aimed to investigate whether plastic polymerization types had regular impacts on larvae growth, gut microbial communities and functional microbes, foam plastics of polypropylene (PP), polyurethane (PU) and ethylene vinyl acetate (EVA) were selected as the representatives of different polymerized plastic and sole diets for yellow mealworms of Tenebrio molitor larvae for 45 days, with sole bran diet as control. Our findings showed that although slightly weight gains were obtained in plastic-fed groups, the larval survival rates decreased to 61.33 %, 59.67 % and 24.00 % in PP-, PU- and EVA-fed groups, respectively. The EVA-fed group was even lower than the starvation group, indicating that the more complex polymers diet had worse adverse effects on larval survival. The gut bacterial- and fungal-microbiomes assessed by Illumina MiSeq indicated that both gut bacterial and fungal communities shifted upon diets of different polymerization types compared to the control. The gut dominant abundances of Spiroplasma , Acinetobacter and Pseudomonas in PP-fed group were significantly different from that of unclassified Enterobacteriaceae in both PU- and EVA-fed groups. In contrast, all gut fungal communities in plastics-fed groups were similar with the dominants of Rhodotorula and Cryptococcus , but more abundances that had been reported with plastics degradation ability were obtained, such as Aspergillus and Cladosporium. In summary, T. molitor could efficiently degrade complex polymers, albeit with adverse effects. Core gut microbiomes were strongly associated with polymerization types of plastic diet, especially gut fungi. [Display omitted] • Polymerization types influence plastics ingestion and degradation by yellow mealworm. • The first-time report on the EVA plastic biodegradation by yellow mealworms. • Complex polymers diets have significant adverse effects on yellow mealworms. • Gut bacteria of polyolefin-fed group show significant difference from other polymer types. • Gut fungal diversity is strongly associated with polymerization types of plastic diet. [ABSTRACT FROM AUTHOR]

Purpose: There is considerable concern about potential effects associated with exposure to magnetic fields on organisms. Therefore, duration of pupa-adult development and motor behaviour of adults were analyzed in Tenebrio obscursus and T. molitor after exposure to static magnetic field (50 mT). Material and methods: The experimental groups were: Control (kept 5 m from the magnets), groups which pupae and adults were placed closer to the North pole, or closer to the South pole of magnetic dipole. The pupae were exposed to the magnetic field until the moment of adult eclosion. The pupa-adult development dynamics were recorded daily. Subsequently, behaviour (distance travelled, average speed and immobility) of adults exposed to the magnetic field was monitored in a circular open field arena. Results: Static magnetic field did not affect pupa-adult developmental dynamic of examined Tenebrio species. Exposure to magnetic field did not significantly change motor behaviour of T. obscurus adults. The changes in the motor behaviour of T. molitor induced by static magnetic field were opposite in two experimental groups developed closer to the North pole or closer to the South pole of magnetic dipole. Conclusion: Static magnetic field (50 mT) did not affect on pupa-adult development dynamic of two examined Tenebrio species, but modulated their motor behaviour. [ABSTRACT FROM AUTHOR]

The cystine knot protein Spätzle is a Toll receptor ligand that modulates the intracellular signaling cascade involved in the nuclear factor kappa B (NF-κB)-mediated regulation of antimicrobial peptide (AMP)-encoding genes. Spätzle-mediated activation of the Toll pathway is critical for the innate immune responses of insects against Gram-positive bacteria and fungi. In this study, the open reading frame (ORF) sequence of Spätzle-like from T. molitor (TmSpz-like) identified from the RNA sequencing dataset was cloned and sequenced. The 885-bp TmSpz-like ORF encoded a polypeptide of 294 amino acid residues. TmSpz-like comprised a cystine knot domain with six conserved cysteine residues that formed three disulfide bonds. Additionally, TmSpz-like exhibited the highest amino acid sequence similarity with T. castaneum Spätzle (TcSpz). In the phylogenetic tree, TmSpz-like and TcSpz were located within a single cluster. The expression of TmSpz-like was upregulated in the Malpighian tubules and gut tissues of T. molitor. Additionally, the expression of TmSpz-like in the whole body and gut of the larvae was upregulated at 24 h post-E. coli infection. The results of RNA interference experiments revealed that TmSpz-like is critical for the viability of E. coli-infected T. molitor larvae. Eleven AMP-encoding genes were downregulated in the E. coli-infected TmSpz-like knockdown larvae, which suggested that TmSpz-like positively regulated these genes. Additionally, the NF-κB-encoding genes (TmDorX1, TmDorX2, and TmRelish) were downregulated in the E. coli-infected TmSpz-like knockdown larvae. Thus, TmSpz-like plays a critical role in the regulation of AMP production in T. molitor in response to E. coli infection. [ABSTRACT FROM AUTHOR]

• Potential of yellow mealworm (YMW) oil in hummus and crackers was examined. • Comparison between crude and deodorized YMW oil was made. • Deodorized YMW oil could replace 100% of vegetable oil without changing acceptance. • Crude oil lead to different perception of certain flavor attributes. • Vegetable oil and YMW oil blends improves the flavor of this insect oil. Introducing processed insects in food products is seen as a way to lower the barrier for insect consumption by Western consumers. Prior research indicated that crude insect lipids could partially replace butter in bakery products without influencing consumer's perception, but a complete substitution remained a challenge due to the presence of off-flavors. This study proposes oil deodorization as a means to reduce insect oil off-flavors and increase insect oil replacement in food products. We compared the effect of deodorization of yellow mealworm (YMW, Tenebrio molitor) oil on the partial and total replacement of vegetable oil in crackers and hummus. In total 253 participants joined the study (127 crackers study, 126 hummus study). Each participant evaluated 5 samples, 100% vegetable oil, 100% crude YMW oil, 100% deodorized YMW oil, 50% vegetable & 50% crude YMW oil and 50% vegetable & 50% deodorized YMW oil. Results showed that deodorized YMW oil could replace vegetable oil in both products without changing the overall food experience, liking and visual appearance in the products. In contrast, using crude YMW oil impacted the overall liking and certain sensory attributes, mostly related to flavor. Moreover, the use of deodorized YMW eliminated visual differences amongst the products. When YMW oil was used in a dispersion-like food, such as hummus, a less firm, more spreadable and less sticky hummus was obtained. Crude YMW oil also reduced hardness in low-moisture solid foods, such as crackers but further studies are necessary to fully understand this effect. [ABSTRACT FROM AUTHOR]

In the case of Tenebrionidae family insects, studies focus on larval stage, leaving a lack of information regarding other stages. Therefore, this study was performed in order to understand the differences between the nutritional composition and the bioactivity of two species of this family in their adult stage, fed with a specific diet. Adult beetles of both species were defatted, lyophilized and protein extracted with buffer. Proximal and phytochemical analysis of the extracts of each insect were performed, along with protein extract and hydrolysis analysis by Tris-Tricine and Tris Glycine SDS PAGE. This analysis showed that T. molitor contained more protein and fat than U. dermestoides but contained less crude fiber. The protein extraction was made with PBS, where 130 and 45 kDa bands showed predominant for U. dermestoides, and less protein was present for T. molitor. Antioxidant and antimicrobial activities of the enzymatic protein hydrolysates and protein crude extracts were determined. Presence of protein associated with the antioxidant activity were found in both insects. Nonetheless U. dermestoides had a higher antioxidant activity with the protein extract in contrast with the higher antioxidant activity shown by U. dermestoides once the extracts were digested. After proteolysis, protein extracts showed an increasing antioxidant activity, plus, the ability to inhibit microbial growth of Proteus, Shigella and Bacillus. Insect protein hydrolysates with protease open the possibility for the use of these beetles as new sources of encrypted peptides for microbiological control once characterized. [ABSTRACT FROM AUTHOR]