Tenebrio Molitor Research Articles

Exploring Tenebrio molitor as a source of low-molecular-weight antimicrobial peptides using a n in silico approach: correlation of molecular features and molecular docking.

Yellow mealworm (Tenebrio molitor) larvae are increasingly recognized as a potential source of bioactive peptides due to their high protein content. Antimicrobial peptides from sustainable sources are a research topic of interest. This study aims to characterize the peptidome of T. molitor flour and an Alcalase-derived hydrolysate, and to explore the potential presence of antimicrobial peptides using in silico analyses, including prediction tools, molecular docking and parameter correlations. T. molitor protein was hydrolysed using Alcalase, resulting in a hydrolysate (TMH10A) with a 10% degree of hydrolysis. The peptidome was analysed using LC-TIMS-MS/MS, yielding over 6000 sequences. These sequences were filtered using the PeptideRanker tool, selecting the top 100 sequences with scores >0.8. Bioactivity predictions indicated that specific peptides, particularly WLNSKGGF and GFIPYEPFLKKMMA, showed significant antimicrobial potential, particularly against bacteria, fungi and viruses. Correlations were found between antifungal activity and physicochemical properties such as net charge, hydrophobicity and isoelectric point. The study identified specific T. molitor-derived peptides with strong predicted antimicrobial activity through in silico analysis. These peptides, particularly WLNSKGGF and GFIPYEPFLKKMMA, might offer potential applications in food safety and healthcare. Further experimental validation is required to confirm their efficacy. © 2024 The Author(s). Journal of the Science of Food and Agriculture published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.

Tenebrio molitor (Mealworm) protein as a sustainable dietary strategy to improve health span in D-galactose-induced aged mice

Aging is an irreversible and continuous biological process involving intricate and interconnected mechanisms. The present work is focused on unravelling the anti-aging mechanisms of mealworm protein and protein-enriched fruit bar and vegetable soup in D-galactose-induced aged mice. Mealworm protein and enriched products significantly enhanced body weight, organ indices, and gut health. Behavioral assessments reflected enhanced neuroprotective effects. Mealworm protein and its enriched products demonstrated protective effects through anti-inflammatory activity with the highest reduction of TNFα (17.1 %), IL-6 (55.5 %), and IL-1β (75.1 %) levels and upregulated the anti-inflammatory marker (IL-4). Gene expression studies confirmed the induction of anti-aging effects by promoting metabolism, reducing cellular senescence, and enhancing anti-oxidant enzyme activity. The treatments extended telomere lengths by 3–4 times, further affirming the potential anti-aging efficacy of mealworm protein and its enriched products. Mealworm protein demonstrated positive effects on weight gain, anti-inflammatory responses, and telomere length; while fruit and vegetable products enhanced antioxidant activity, and positively influenced gut health. Further, a synergistic effect was observed by combining them, which resulted in improved overall anti-aging effect. The present work provides valuable insights into the multifaceted anti-aging mechanisms associated with mealworm protein and enriched products, highlighting their potential as functional foods with significant health-promoting effects.

HPLC-MS/MS and ICP-MS for Evaluation of Mycotoxins and Heavy Metals in Edible Insects and Their Defatted Cakes Resulting from Supercritical Fluid Extraction.

Edible Insects (EIs) are an alternative source of bioactive compounds such as proteins or fatty acids and micronutrients as vitamins or minerals, thus showing potential to replace traditional foodstuffs in an economical and environmentally friendly way. Nonetheless, EIs can accumulate hazardous chemicals such as mycotoxins and heavy metals. The aim of the present study is to determine mycotoxins and heavy metal content in raw insect samples and those resulting products obtained after supercritical fluid extraction (SFE). Insect samples included Acheta domesticus (cricket) meal, Tenebrio molitor (mealworm) meal, Alphitobius diaperinus (buffalo worm), and Locusta migratoria (locust). For this purpose, a QuEChERS method followed by LC-MS/MS analysis was optimized with good results for the analysis of mycotoxins, principally Aflatoxins (AFs), Ochratoxin A (OTA), and Enniatins (ENNs). In contrast, heavy metals (As, Cd, Hg, Pb) were determined by Inductively Coupled Plasma Mass Spectrometry (ICP-MS). The results obtained revealed that Locust was positive for AFG2 at a level of 115.5 μg/kg, and mealworm was only contaminated with OTA at 58.1 μg/kg. Emerging mycotoxins (ENNA, ENNA1, ENNB, and ENNB1) were detected at lower levels < 2.2 µg/Kg. Concerning heavy metals, limits exceeding regulation were detected for Cd in the insect species studied, with levels up to 219 μg/kg, and for Pb in crickets (100.3 μg/kg). Finally, the analysis of the post-extraction solids after SFE processing revealed that heavy metals remained in the resulting SFE cakes, while mycotoxins were detected at negligible levels (up to 1.3 µg/Kg).

Pathogenicity of psychrotolerant strains of Antarctic Pseudogmynoascus fungi reveals potential opportunistic profiles

Recent studies have demonstrated the presence of fungal taxa in the extreme ecosystems of Antarctica that are known to opportunistically infect humans and animals. Among these are members of the genus Pseudogymnoascus, including some that are genetically similar to P. destructans, known to be pathogenic to bats. We evaluated the in vitro and in vivo pathogenic potential of 11 Pseudogymnoascus spp. strains recovered from Antarctica. All strains were able to grow at temperatures up to 28 °C and displayed in vitro pathogenicity through hemolytic activity, growth at different pH levels, production of hydrolytic enzymes, spore diameters, tolerance to oxidative stress, hypoxia, and halotolerance. Among them, Pseudogymnoascus sp. UFMG 8532 exhibited strong in vitro pathogenicity and in preliminary in vivo assay killed 100 % of Tenebrio molitor larvae within one day. The pathogenicity of the same strain was also tested using immunosuppressed BALB/c mouse models. Survival of BALB/c mice was affected, with oscillations between weight gain and loss, and impacts on sensory function, reflexes and autonomic function. Histopathological data from the organs of infected mice showed evidence of inflammatory processes, with numerous neutrophils, a small number of macrophages, fluid accumulation inside the lungs and intense hyperemia. Our results indicate that Antarctic Pseudogymnoascus spp. strains obtained from various substrates/habitats in maritime Antarctica may possess intrinsic virulence factors and pathogenic potential for immunosuppressed animals and humans in the region. Given that the Antarctic environment is an important reservoir for Pseudogymnoascus species, which display growth performance across a range of temperatures, it is possible that increasing temperatures in the maritime Antarctic could activate dormant genes or biochemical pathways, select virulent species and/or strains, and facilitate their spread within and beyond the region. The ability of Pseudogymnoascus species to grow slowly even at 28°C, coupled with their potential in vitro and in vivo virulence factors, suggests that these fungi might be undergoing an opportunistic transition due to the effects of climate change on the Antarctic Peninsula.

Auranofin is active against Histoplasma capsulatum and reduces the expression of virulence-related genes.

Auranofin is an approved anti-rheumatic drug that has a broad-range inhibitory action against several microorganisms, including human pathogenic fungi. The auranofin activity against Histoplasma capsulatum, the dimorphic fungus that causes histoplasmosis, has not been properly addressed. Since there are few therapeutic options for this life-threatening systemic mycosis, this study evaluated the effects of auranofin on H. capsulatum growth and expression of virulence factors. Minimal inhibitory and fungicidal concentrations (MIC and MFC, respectively) of auranofin against 15 H. capsulatum strains with distinct genetic backgrounds were determined using the yeast form of the fungus and a microdilution protocol. Auranofin activity was also assessed on a macrophage model of infection and on a Tenebrio molitor invertebrate animal model. Expression of virulence-related genes was compared between auranofin treated and untreated H. capsulatum yeast cells using a quantitative PCR assay. Auranofin affected the growth of different strains of H. capsulatum, with MIC and MFC values ranging from 1.25 to 5.0 μM and from 2.5 to >10 μM, respectively. Auranofin was able to kill intracellular H. capsulatum yeast cells and conferred protection against the fungus in the experimental animal model of infection. Moreover, the expression of catalase A, HSP70, superoxide dismutase, thioredoxin reductase, serine proteinase, cytochrome C peroxidase, histone 2B, formamidase, metallopeptidase, Y20 and YPS3 proteins were reduced after six hours of auranofin treatment. CONCLUSIONS/SIGNIFICANCE: Auranofin is fungicidal against H. capsulatum and reduces the expression of several virulence-related genes, which makes this anti-rheumatic drug a good candidate for new medicines against histoplasmosis.

Enhancing the insecticidal efficacy of Allium sativum extracts through microencapsulation via complex coacervation

Garlic (Allium sativum L.) has been widely studied for its insecticidal properties. The primary bioactive molecule in garlic extracts include allicin, alliin, S-allylcysteine, diallyl disulfide, diallyl trisulfide, diallyl sulfide and ajoene. However, these compounds degrade under environmental conditions once extracted. This study aimed to enhance the effectiveness of garlic extracts in controlling Tenebrio molitor by optimizing microencapsulation techniques. The garlic extracts were encapsulated using the complex coacervation method, with independent variables including pH levels (3, 6 and 9), whey protein isolate (WPI) (4 %, 6 % and 8 % w/v) and pectin (0.50 %, 0.75 % and 1.00 % w/v). A Taguchi L9 (33) orthogonal array was employed to design 9 treatments, and T. molitor mortality was assessed 72 h after a 10 sec immersion of the insects in the treatments. Statistical analysis revealed that WPI had the most significant influence (24.52 %), followed by pH (18.82 %) and pectin (7.79 %). The interaction between pH and pectin had the greatest effect on the encapsulation process, accounting for 38.65 % of the influence. The optimal microencapsulation conditions were predicted by software to be pH 3, a pectin concentration of 0.75 % w/v and a WPI concentration of 4.00 % w/v, resulting in a signal-to-noise (S/N) ratio of 42.30. Experimental validation of these conditions produced an S/N ratio of 18.54, corresponding to a T. molitor mortality rate of 92 % ± 4.47 %. The resulting microcapsules had diameters ranging from 1–5 ?m. Complex coacervation is a highly promising method for microencapsulating garlic extracts and preserving their insecticidal properties.

Effect of the Addition of Yellow Mealworm (Tenebrio molitor) on the Physicochemical, Antioxidative, and Sensory Properties of Oatmeal Cookies

Edible insects are receiving increased attention as a new food source, although research on their implementation in confectionary products remains scarce. The study analyzed the chemical composition, physical parameters, antioxidative, and sensory characteristics of oatmeal cookies reformulated with yellow mealworm larvae (Tenebrio molitor L.; TM) at 0% (TM0), 10% (TM10), and 30% (TM30). The inclusion of TM in the cookie recipe increased the protein and fat content, improved the ratio of n-6/n-3 acids, and raised oleic acid levels while reducing palmitic acid. Oatmeal cookies were rich in K and P, and including TM significantly increased the content of most minerals, except for Mn and Na. The cookies held significant antioxidant capacity that increased as the concentration of TM increased due to hydrophilic antioxidants. Although lightness decreased with the increase in mealworm substitution, the yellowness, chroma, and hue angle remained similar for TM0 and TM10. The TM30 cookies were significantly darker and softer, which was further confirmed by panelists. The cookie formulation effectively masked the taste and smell of TM since there were no evident differences between the control and TM10 cookies. Cookies with TM30 received high enough ratings to be considered attractive if differentiated sensory characteristics are desired.

The Nutritional Quality of Commercially Bred Yellow Mealworm (Tenebrio molitor) Compared to European Union Nutrition Claims.

Due to its potential as a sustainable protein source, the industrial relevance of Tenebrio molitor, known as yellow mealworm, is set to increase substantially. Given the novelty of its application in the food industry, knowledge is lacking regarding the nutritional quality of commercially farmed mealworms. This study investigated the nutritional composition of larvae from four different rearing facilities in Belgium and specifically investigated whether their nutritional profiles adhered to defined European nutrition claims (Regulation (EC) No. 1924/2006). In particular, the European nutrition claims "high in protein", "high unsaturated fat", "high in fibre" and "rich in P, Mg, K, Zn and Mn" were applicable for all mealworm samples on a dry matter basis. On a fresh matter basis, yellow mealworms were found to be "high in protein", "high unsaturated fat" and "low in sugar".

Marine Bacillus pumilus substances exhibit antimicrobial effect on multidrug-resistant Staphylococcus aureus.

This study aimed to assess the antimicrobial potential of Bp1-AdE, produced by Bacillus pumilus 64-1, and to investigate its mode of action against Staphylococcus aureus and methicillin-resistant S. aureus (MRSA). Bp-1AdE, derived from sponge-associated B. pumilus, exhibited bactericidal activity at 1 550µg ml-1 against S. aureus ATCC29213 and MRSA strains. Light and fluorescence microscopy revealed drastic cell lysis of S. aureus treated with Bp-1AdE. Scanning and transmission electron microscopy suggested that Bp-1AdE disrupts the cytoplasmic membrane. Toxicity assays showed that Bp-1AdE was non-toxic to Tenebrio molitor larvae. Liquid chromatography-mass spectrometry and Global Natural Product Social spectral libraries identified four substances within Bp-1AdE, including aliphatic alcohols [3,4-dipentylhexane-2,5-diol and 1,1'-(4,5-dibutyl-3,6-dimethylcyclohexane-1,2-diyl)bis(ethan-1-one)] and terpenoids (cholic acid and canrenone). Bp-1AdE demonstrated selective toxicity and bactericidal activity, highlighting its potential for controlling infections caused by multidrug-resistant S. aureus strains.

Eco-friendly technologies for obtaining antioxidant compounds and protein hydrolysates from edible insect Tenebrio molitor beetles

The functional properties of edible insects can be explored by a joint use of novel technologies. This work applied varied pre-treatments (ultra-sound-assisted extraction, UAE; microwave-assisted extraction, MAE; temperature-assisted extraction, TAE; CO2-assisted extraction) and solvents (water, ethanol, water:ethanol) in Tenebrio molitor beetles to enhance the extraction of phenolic compounds with antioxidant activity. An enzymatic hydrolysis (EH) was performed in wet and treated biomasses to determine the protein hydrolysis. Higher phenolic compounds and antioxidant activity was released after MAE using water as solvent compared to the other treatments and solvents. Treatments decreased 32 %, 19 % and 30 % the protein, chitin and lipids content. EH improved protein and amino acids hydrolysis in the MAE-treated insects, followed by UAE and TAE treatments. In conclusion, MAE was the most effective to release phenolics and antioxidant activity from T. molitor beetles, while using MAE followed by EH improved protein and amino acids hydrolysis, envisioning valuable applications for this insect biomass.

A tomato a day keeps the beetle away - the impact of Solanaceae glycoalkaloids on energy management in the mealworm Tenebrio molitor.

Solanine (SOL), chaconine (CHA), and tomatine (TOM) are plant secondary metabolites produced mainly by the species of Solanaceae family, such as tomato Solanum lycopersicum L. These glycoalkaloids (GAs) have a wide range of biological activity, also in insects. However, their mechanisms of action are not precisely understood. The purpose of the study was to investigate how pure GAs and tomato leaf extract (EXT) affect glycolysis, Krebs cycle and β-oxidation of fatty acid pathways in Tenebrio molitor L. beetle. For this purpose, the larvae were injected with SOL, CHA, TOM, and EXT at two concentrations (10-8 and 10-5M). For experiments, fat body, gut, and heamolymph samples were collected 2 and 24h after injection. Then, the changes in the expression level of phosphofructokinase, citrate synthase, and β-hydroxyacyl-CoA dehydrogenase were measured using the RT-qPCR technique. The catalytic activity of these enzymes and the carbohydrate level in insects after GA treatment were determined by spectrophotometric method. Furthermore, the analysis of the amount of amino acids in tissues was performed with a GC-MS technique. The results obtained show that the GAs changed the activity and expression of the genes encoding key enzymes of crucial metabolic pathways. The effect depends on the type of GA compound, the tissue tested, and the incubation time after treatment. Furthermore, TOM and EXT affected trehalose concentration in the insect hemolymph and led to accumulation of amino acids in the fat body. The observed changes may indicate a protein degradation and/or enhanced catabolism reactions for the production of ATP used in detoxification processes. These results suggest that GAs alter energy metabolism in the mealworm T. molitor. The study contributes to our understanding of the mechanisms of action of secondary metabolites of plants in insects. This knowledge may allow the design of new natural biopesticides against insect pests because proper energy metabolism is necessary for the survival of the organism.

Novel Feruloyl Esterase for the Degradation of Polyethylene Terephthalate (PET) Screened from the Gut Microbiome of Plastic-Degrading Mealworms (Tenebrio Molitor Larvae).

Mealworms (Tenebrio molitor) larvae can degrade both plastics and lignocellulose through synergistic biological activities of their gut microbiota because they share similarities in chemical and physical properties. Here, a total of 428 genes encoding lignocellulose-degrading enzymes were screened from the gut microbiome of T. molitor larvae to identify poly(ethylene terephthalate) (PET)-degrading activities. Five genes were successfully expressed in E. coli, among which a feruloyl esterase-like enzyme named TmFae-PETase demonstrated the highest PET degradation activity, converting PET into MHET (0.7 mgMHETeq ·h-1·mgenzyme-1) and TPA (0.2 mgTPAeq ·h-1·mgenzyme-1) at 50 °C. TmFae-PETase showed a preference for the hydrolysis of ferulic acid methyl ester (MFA) in the presence of both PET and MFA. Site-directed mutagenesis and molecular dynamics simulations of TmFae-PETase revealed similar catalytic mechanisms for both PET and MFA. TmFae-PETase effectively depolymerized commercial PET, making it a promising candidate for application. Additionally, the known PET hydrolases IsPETase, FsC, and LCC also hydrolyzed MFA, indicating a potential origin of PET hydrolytic activity from its lignocellulosic-degrading abilities. This study provides an innovative strategy for screening PET-degrading enzymes identified from lignocellulose degradation-related enzymes within the gut microbiome of plastic-degrading mealworms. This discovery expands the existing pool of plastic-degrading enzymes available for resource recovery and bioremediation applications.

Interactions between feed protein source and feeding frequency on growth performance and health status of largemouth bass (Micropterus salmoides).

In order to evaluate the effects of the interaction between different proteins and feeding frequency on largemouth bass (Micropterus salmoides) and to provide scientific guidance for the application of novel proteins and the corresponding optimal feeding strategy, a two-factorial design (5 × 3) with five protein feeds (fishmeal (FM), Clostridium autoethanogenum protein (CAP), Tenebrio molitor (TM), Chlorella meal (ChM), cottonseed protein concentrate (CPC)), and three feeding frequency (1, 2, and 3 times/d; FF1, FF2, FF3) was designed in culturing largemouth bass (initial weight, 2.98 ± 0.22g/fish) for 8weeks. Z-score combined with cluster analysis was used to analyze and compare the effects of different treatments on different indicators, such as growth performance, feed utilization, antioxidant capacity, and immune response to draw a general picture of the relationship among all these massive biomarkers. The results showed that different protein sources and feeding frequencies had significant interactive effects on growth performance, feed utilization efficiency, body lipid, and health status of largemouth bass. Fish fed with ChM feed showed similar performance to that in FM group, implying its potential for complete replacement of fishmeal in largemouth bass. Fish fed with CAP, TM, and CPC feeds showed worse performance compared to FM and ChM groups, characterized by poor growth and feed utilization, enhanced stress, chronic inflammation, and varying symptoms of histological changes in the liver and intestine, which demonstrated the adverse effects of the complete replacement of fishmeal by these three proteins. In terms of feeding frequency, fish fed with FM feed in FF3 group led to liver hypertrophy, fat accumulation, and the risk of fatty liver, while inducing liver inflammation. In addition, the TM and CAP group had the higher expression levels of inflammatory factors at FF3 group, which displayed that the interactions between FM, CAP, TM feeds and feeding frequency at FF3 might aggravate the occurrence of liver inflammation and oxidative damage of hepatocytes. Overall, FF2 had higher feed efficiency, protein efficiency, antioxidant enzyme and lysozyme activities, lower MDA content, and lower gene expression of inflammatory cytokines and could be considered as the optimum feeding frequency for largemouth bass fed with different protein feeds.

Study of the effect of feeding Tenebrio molitor larvae during their rearing on their growth, nutritional profile, value and safety of the produced flour

Science and food industry must strive to ensure and improve edible insect's benefits, and especially their safety and nutritional value. This study investigated how various food substrates used in the rearing of Tenebrio molitor larvae influence their growth, the safety of the larvae, and the nutritional quality of the resulting flour. The main findings indicate that all samples showed significant differences in their nutritional profile, larval characteristics, and heavy metal content. Regarding the content of protein, fat and fiber it ranges from 44.1 to 51.8 %, 28.6–34.8 % and 10.5–14.9 %, respectively. These results suggest that insect diet is a very crucial parameter that can affect all that factors and must be taken into account, especially when they are intended as raw materials to be used for food production.

A Comparative Analysis of Different Xenorhabdus Strains Reveals a Virulent Factor, Cyclic Pro-Phe, Using a Differential Expression Profile Analysis of Non-Ribosomal Peptide Synthetases.

Entomopathogenic bacteria, classified into the genus Xenorhabdus, exhibit a dual lifestyle as mutualistic symbionts to Steinernema nematodes and as pathogens to a broad range of insects. Bacterial virulence depends on toxin proteins that induce toxemia and various immunosuppressive secondary metabolites that cause septicemia. Particularly, the immunosuppressive properties of Xenorhabdus bacteria determine the variability of their insecticidal activities. This study explored the role of peptide metabolites in virulence and its variation among six bacterial strains across three species: X. nematophila, X. bovienii, and X. hominickii. Initially, their virulence significantly varied against a susceptible lepidopteran host, Maruca vitrata, but showed less variation against a tolerant coleopteran host, Tenebrio molitor, with high median lethal bacterial doses. In M. vitrata, virulence was strongly correlated with bacterial growth rate and inhibitory activity against phospholipase A2. Secondly, the six strains differed in the compositions of their secreted secondary metabolites, analyzed by GC-MS following ethyl acetate extraction. Notably, there was significant variation in the production of di- or tetra-peptides. Highly virulent strains commonly produced the cyclic Pro-Phe (cPF). Thirdly, the expression of non-ribosomal peptide synthetase (NRPS) genes varied greatly among the strains. NRPS genes were minimally expressed in the tolerant T. molitor and highly expressed in the susceptible M. vitrata. In M. vitrata, specific NRPS genes were markedly expressed in the virulent strains. Finally, cPF demonstrated potent immunosuppressive activity against the cellular and humoral responses of M. vitrata. The addition of cPF significantly enhanced the virulence against the tolerant T. molitor. These findings suggest that immunosuppression is necessary for the pathogenicity of Xenorhabdus bacteria, wherein NRPS products play a critical role in suppressing immune-associated factors in target insects.

Goal-directed behavior in Tenebrio molitor larvae

Can signs of intentional behavior be traced in an insect larva, traditionally thought to be driven only by mere reflexes? We trained Tenebrio molitor coleoptera larvae in a uniform Y-maze to prefer one target branch to get access to food, observing their ability to learn and retain access to the reward-associated side for up to 24 h. During reward devaluation, the reward food (experimental group) and a different food (control group) were paired with an aversive stimulus in a new environment. When tested again in the Y-maze, mealworms of the experimental group significantly reduced their visits to the target branch, whereas mealworms of the control group did not. Importantly, we found that the larvae did not have to experience the unpleasant consequences directly in the target branch to halt their behavior, as the exposure to the aversive taste occurred in a separate unfamiliar context. This is evidence that the mealworms formed a mental representation of action-consequence relationships, demonstrating flexible control of their actions to achieve desired outcomes at an early stage of their development.

Actinomycin D reduces virulence factors and biofilms against Aeromonas hydrophila.

Aeromonas hydrophila, a Gram-negative bacterium, is ubiquitously found in many aquatic habitats, causing septicemia in humans and fishes. Attributed to abuse or misuse of conventional antimicrobial drug usage, antimicrobial resistance is at an alarming rise. There is an available alternative strategy to bacterial resistance to antimicrobials, which is inhibition of virulence and pathogenicity employing quorum sensing inhibitors (QSIs). Hence, actinomycin D's effectiveness against A. hydrophila SHAe 115 as a QSI was investigated in decreasing virulence factors and preventing biofilm formation. Actinomycin D, belongs to the QSI combating Pseudomonas aeruginosa PAO1 originally isolated from an entophytic actinomycete (Streptomyces cyaneochromogenes RC1) in Areca catechu L. In the present work, further investigations were carried out to assess the effect of actinomycin D at subminimal inhibitory concentrations (sub-MICs), QS-regulated virulence factors, and biofilm inhibition strategies. Intrinsic properties encompassing inhibition of the production of protease and hemolysin and subsequent activities on biofilm formation and eradication of mature biofilm were established along with weakened swimming and swarming motilities in A. hydrophila SHAe 115. In the Tenebrio molitor survival assay, actinomycin D effectively reduced the virulence and pathogenicity of A. hydrophila, resulting in elimination of mortality. However, the hydrolysate of actinomycin D, 2-hydroxy-4,6-dimethyl-3-oxo-3H-phenoxazine-1,9-dicarboxylic acid (HDPD), had lost the QSI activity in A. hydrophila. Actinomycin D was proved as a viable QSI in lessening A. hydrophila's the virulence and pathogenicity, as evident from our research findings.

Tenebrio molitor flour as a partial fish replacer and its effect on the quality of hake sausages

Tenebrio molitor flour as a partial fish replacer and its effect on the quality of hake sausages

Effects of plastic aging on biodegradation of polystyrene by Tenebrio molitor larvae: Insights into gut microbiome and bacterial metabolism

Plastics aging reduces resistance to microbial degradation. Plastivore Tenebrio molitor rapidly biodegrades polystyrene (PS, size: < 80 μm), but the effects of aging on PS biodegradation by T. molitor remain uncharacterized. This study examined PS biodegradation over 24 days following three pre-treatments: freezing with UV exposure (PS1), UV exposure (PS2), and freezing (PS3), compared to pristine PS (PSv) microplastic. The pretreatments deteriorated PS polymers, resulting in slightly higher specific PS consumption (602.8, 586.1, 566.7, and 563.9 mg PS·100 larvae−1·d−1, respectively) and mass reduction rates (49.6 %, 49.5 %, 49.2 %, and 48.7 %, respectively) in PS1, PS2, and PS3 compared to PSv. Improved biodegradation correlated with reduced molecular weights and the formation of oxidized functional groups. Larvae fed more aged PS exhibited greater gut microbial diversity, with microbial community and metabolic pathways shaped by PS aging, as supported by co-occurrence network analysis. These findings indicated that the aging treatments enhanced PS biodegradation by only limited extent but impacted greater on gut microbiome and bacterial metabolic genes, indicating that the T. molitor host have highly predominant capability to digest PS plastics and alters gut microbiome to adapt the PS polymers fed to them.

Chromosome-level genome assembly of the medicinal insect Blaps rhynchopetera using Nanopore and Hi-C technologies.

Blaps rhynchopetera Fairmaire is a significant medicinal resource in southwestern China. We utilized Nanopore and Hi-C technologies in combination to generate a high-quality, chromosome-level assembly of the B. rhynchopetera genome and described its genetic features. Genome surveys revealed that B. rhynchopetera is a highly heterozygous species. The assembled genome was 379.24Mb in size, of which 96.03% was assigned to 20 pseudochromosomes. A total of 212.93Mb of repeat sequences were annotated, and 26,824 protein-coding genes and 837 noncoding RNAs were identified. Phylogenetic analysis indicated the divergence of the ancestors of B. rhynchopetera and its closely related species Tenebrio molitor at about 85.6 million years ago. The colinearity analysis showed that some chromosomes of B. rhynchopetera may have had fission events, and it has a good synteny relationship with Tribolium castaneum. Furthermore, in the enrichment analyses, the gene families related to detoxification and immunity of B. rhynchopetera facilitated the understanding of its environmental adaptations, which will serve as a valuable research resource for pest control strategies and conservation efforts of beneficial insects. This high-quality reference genome will also contribute to the conservation of insect species diversity and genetic resources.