The Edible Insect Gryllus bimaculatus Protects against Gut-Derived Inflammatory Responses and Liver Damage in Mice after Acute Alcohol Exposure

Effects of Gryllus bimaculatus and Oxya chinensis sinuosa extracts on brain damage via blood-brain barrier control and apoptosis in mice with pentylenetetrazol-induced epilepsy

The demand for environmentally friendly foods with high nutritional value and low carbon emissions is increasing with the aging of the global population and the crisis of food resources. Edible insects are becoming increasingly well-known as such foods. This study evaluated the effects and mechanisms of Gryllus bimaculatus (Cricket) (Gb) and Oxya chinensis sinuosa (Grasshopper) (Ocs) extracts on epilepsy. A pentylenetetrazol (PTZ)-induced seizure mouse model was used for the study, and Gb and Ocs extracts were administered for 29 days on alternate days at concentrations of 8 g/kg and 16 g/kg. The integrity of the blood-brain barrier (BBB) and brain edema was measured using the perfusion of Evans blue dye and brain water content. Gb and Ocs extracts prevented BBB permeabilization and cerebral edema through increasing the expression of tight junction-associated proteins in the endothelial cells and reducing water content in PTZ-treated mice. Additionally, Gb and Ocs extracts protected neurons from oxidative stress and apoptosis in different brain areas. These protective effects were demonstrated through the restoration of the expression of neuronal nuclear protein and postsynaptic density protein-95, thus increasing the levels of glutathione and superoxide dismutase, decreasing lipid peroxidation, and recovering apoptosis-associated proteins, such as Bax, cleaved PARP, and cleaved caspase-3, in epileptic mice. In addition, Gb and Ocs extracts rescued PTZ-induced hyperexcitable neurons to control mice level, as supported by the restored expression of gamma-aminobutyric acid (GABA) transporter 1, the metabotropic glutamate receptors-GRM2/3, and BDNF. This study suggested that Gb and Ocs extracts are novel medicinal candidates that can help ameliorate epilepsy by improving BBB health and preventing oxidative stress-mediated apoptosis.

Unraveling the physicochemical attributes of three cricket (Gryllus bimaculatus)-enriched biscuit products and implications on consumers' preference and willingness to pay

Disgust and neophobia elicited by whole insect products, has necessitated the need to mask insect-based food products. The physico-chemical parameters, sensory acceptance, and willingness to pay (WTP) for wheat biscuits supplemented with cricket powder was evaluated. The biscuits' color intensity correlated with the cricket inclusion levels. Spread ration of cricket-enriched-biscuits increased (1.0-1.2-folds), while the hardness and fracturability decreased (1.0-1.3-folds and 1.0-1.2 folds, respectively) compared to the control biscuit. Cricket-biscuits exhibited 1.2-1.7, 1.1-3.7, 1.2-3.0 and 1.1-1.2-folds higher (p < 0.05) protein, ash, fiber, and fat, respectively. Ca, Fe, and Zn were 1.1-3.7, 1.1-1.2 and 1.4-4.0-folds higher, respectively, for cricket-based biscuits. Monounsaturated and polyunsaturated fatty acids proportionally increased with increasing cricket flour. On a likert scale, 71.4%, 71.9%, 38.4% and 57.5% of the caregivers and 38.6%, 58.3%, 40.0% and 34.0% for children (3-5 years) strongly preferred the color, texture, taste and aroma, respectively, of the cricket-based biscuits. Forty-seven (47%) of the caretakers were WTP a premium of 37 Kenyan shillings (0.34 USD) for cricket-based biscuits. Our findings demonstrated that integration of cricket flour into existing market-driven consumer familiar food products significantly increased acceptability and WTP, thus promising potential to contribute to improved food and nutritional security.

Effects of Protein Hydrolysate from Silkworm (Bombyx mori) pupae on the C2C12 Myogenic Differentiation

This study investigated the effects and active compounds of silkworm pupae, an edible insect, on C2C12 muscle differentiation. The protein of silkworm pupae was extracted using sonication after defatting with hexane. Subsequently, the extract was rehydrated using Alcalase to obtain a protein hydrolysate. The silkworm pupae protein hydrolysate effectively promoted C2C12 myogenic differentiation without cytotoxicity. Subsequently, the hydrolysate was fractionated into four subfractions using preparative high-performance liquid chromatography (Prep-HPLC). Subfraction 1 was the most effective in promoting C2C12 myogenic differentiation and significantly upregulated the expression of myoblast transcription factors, 1.5-fold of myoblast determination protein 1 (MyoD), 2-fold of myogenin, and 3-fold of myosin heavy chain (MyHC). Liquid chromatography-tandem mass spectrometry (LC-MS/MS) and multivariate statistical analysis were used to identify the active peptides in silkworm pupae responsible for the observed effects; then, dipeptides and essential amino acids, such as isoleucine (Ile), valine (Val), and methionine (Met), were identified. In addition, Val, Ile, and two dipeptides underwent quantification to determine the potential bioactive peptides that enhanced C2C12 myogenic differentiation. This study suggests that the peptides from silkworm pupae could be used as a nutraceutical to enhance muscle growth.

Insects as food and medicine: a sustainable solution for global health and environmental challenges

Insects are a significant source of food for millions of people worldwide. Since ancient times, insects in medicine have been contributing to the treatment of diseases in humans and animals. Compared to conventional animal farming, the production of insects for food and feed generates significantly less greenhouse gas emissions and uses considerably less land. Edible insects provide many ecosystem services, including pollination, environmental health monitoring, and the decomposition of organic waste materials. Some wild edible insects are pests of cash crops. Thus, harvesting and consuming edible insect pests as food and utilizing them for therapeutic purposes could be a significant progress in the biological control of insect pests. Our review discusses the contribution of edible insects to food and nutritional security. It highlights therapeutic uses of insects and recommends ways to ensure a sustainable insect diet. We stress that the design and implementation of guidelines for producing, harvesting, processing, and consuming edible insects must be prioritized to ensure safe and sustainable use.

Unravelling the potential of insects for medicinal purposes - A comprehensive review

Entomotherapy, the use of insects for medicinal purposes, has been practised for centuries in many countries around the world. More than 2100 edible insect species are eaten by humans, but little is known about the possibility of using these insects as a promising alternative to traditional pharmaceuticals for treating diseases. This review offers a fundamental understanding of the therapeutic applications of insects and how they might be used in medicine. In this review, 235 insect species from 15 orders are reported to be used as medicine. Hymenoptera contains the largest medicinal insect species, followed by Coleoptera, Orthoptera, Lepidoptera, and Blattodea. Scientists have examined and validated the potential uses of insects along with their products and by-products in treating various diseases, and records show that they are primarily used to treat digestive and skin disorders. Insects are known to be rich sources of bioactive compounds, explaining their therapeutic features such as anti-inflammatory, antimicrobial, antiviral, and so on. Challenges associated with the consumption of insects (entomophagy) and their therapeutic uses include regulation barriers and consumer acceptance. Moreover, the overexploitation of medicinal insects in their natural habitat has led to a population crisis, thus necessitating the investigation and development of their mass-rearing procedure. Lastly, this review suggests potential directions for developing insects used in medicine and offers advice for scientists interested in entomotherapy. In future, entomotherapy may become a sustainable and cost-effective solution for treating various ailments and has the potential to revolutionize modern medicine.

Physicochemical and functional properties of capsaicin loaded cricket protein isolate and alginate complexes

As people become more aware of the health benefits of foods and their nutritional benefits for preventing diseases and promoting health, the demand for functional foods rich in proteins, fiber, and bioactives like capsaicin (CAP) is constantly rising. This study hypothesized that the electrostatic complexes developed by cricket protein isolate (CPI) and alginate (AL) could be utilized to encapsulate CAP, making it more water-soluble and protecting it at acidic pHs. Quantitative analysis revealed that CAP was efficiently encapsulated into the CPI-AL complexes with a maximum encapsulation efficiency of 91%, improving its aqueous solubility 45-fold. In vitro release tests showed that CAP was retained at acidic pHs (3.0 and 5.0) in CPI-AL complexes but released steadily at neutral pH (7.4), which will protect CAP in the stomach while enabling its release in the small intestine. Moreover, the antioxidant activity of CAP-CPI-AL complexes was superior to that of their individual bare equivalents. The complexes also demonstrated enhanced emulsifying capabilities and stability at acidic pHs (2.0-5.0) as the CPI fraction in the complexes increased. Our findings thus contribute to the growing body of knowledge that validates protein-polysaccharide complexation as a promising strategy for developing edible delivery systems.

Innovation in Alternative Food Sources: A Review of a Technological State-of-the-Art of Insects in Food Products

Insects present great potential for the food industry due to their easier rearing conditions and high nutritional value, in comparison with traditional livestock. However, there is a lack of evaluation of the technological status of food products developed with edible insects. Therefore, this study aims to analyze the emergent technological and scientific applications of edible insects in the food industry through a prospective study of patent documents and research articles. Espacenet was used as a research tool, applying the terms Insect, Pupa, Larva, or Nymph and the codes A23L33 and A23V2002. A total of 1139 documents were found-341 were related to the study. Orbit^® was used to evaluate technological domains and clusters of concepts. Scopus database research was performed to assess the prevalence of insect research, with the term "edible and insect*". The main insects used were silkworms, bees, beetles, mealworms, crickets, and cicadas. Protein isolates were the predominant technology, as they function as an ingredient in food products or supplements. A diverse application possibility for insects was found due to their nutritional composition. The insect market is expected to increase significantly in the next years, representing an opportunity to develop novel high-quality/sustainable products.

The Chemical Composition and Antimitotic, Antioxidant, Antibacterial and Cytotoxic Properties of the Defensive Gland Extract of the Beetle, Luprops tristis Fabricius

The unpredictable invasion of the Mupli beetle, Luprops tristis Fabricius (Coleoptera: Tenebrionidae), makes areas uninhabitable to humans. These beetles produce a strong-smelling, irritating secretion as a defence mechanism, which causes blisters on contact with human skin. In the current study, gas chromatography high-resolution mass spectrometry (GC-HRMS) analysis of the defensive gland extract of the Mupli beetle revealed the presence of compounds such as 2,3,dimethyl-1,4-benzoquinone, 1,3-dihydroxy-2-methylbenzene, 2,5-dimethyl hydroquinone, tetracosane, oleic acid, hexacosane, pentacosane, 7-hexadecenal and tert-hexadecanethiol. The defensive gland extracts showed considerable antibacterial activity on Gram-negative and Gram-positive bacteria in an agar diffusion assay. The chromosomal aberration analysis using root tips of Allium cepa L. exposed to the defensive secretion showed chromosomal aberrations such as disturbed metaphase, sticky chromosomes and chromosomal breakage. The antioxidant activity of the extract was determined using a radical scavenging (DPPH) assay. A cytotoxic assay of the defensive gland extract against Dalton's lymphoma ascites (DLA) cell line showed anticancer properties. In the present study, the defensive gland extract of the Mupli beetle, L. tristis, which is generally perceived as a nuisance insect to humans, was found to have beneficial biological activities.

Protective effects of E Se tea extracts against alcoholic fatty liver disease induced by high fat/alcohol diet: In vivo biological evaluation and molecular docking study

BACKGROUND

With the development of economy and increased workload, chronic a high-fat/alcohol diet intake may lead to alcoholic fatty liver disease (AFLD), which is considered as a crucial health problem worldwide. E Se tea is produced of the leaves and leaf buds of Malus toringoides (Rehd.) Hughes in Tibet and has human health benefits with anti-hyperglycemia, hypertension, and hyperlipidemia effects.

PURPOSE

The objective of this work was to investigate the protective effect of aqueous-ethanol and hot-water extracts of E Se tea against chronic high-fat/alcohol diet induced AFLD rats.

METHODS

Firstly, to determine the chemical profiling of E Se tea extracts, UHPLC-ESI-HRMS analysis was conducted. Secondly, Sprague-Dawley male rats were used to establish the AFLD animal model by feeding with high-fat/alcohol diet. The animals were treated with E Se tea extracts for 12 weeks. Serum parameters were determined, histologic sections were prepared, and activities of enzymes related to inflammatory response and lipid metabolism imbalance were analyzed. The underlying mechanisms of E Se tea extracts alleviating AFLD were analyzed by immunofluorescence staining and Western blotting analysis. Lastly, key targets of 11-MT against AFLD were verified through molecular docking.

RESULTS

In this study, seven main compounds were confirmed or tentatively identified in E Se tea extracts by UHPLC-ESI-HRMS. The results revealed that both the extracts could reverse histopathological steatotic alternation of the liver and reduced the activity of liver damage markers (ALT, AST). E Se tea extracts mitigated oxidative stress by inhibiting CYP2E1 protein and lipid peroxidation parameters (MDA), but enhancing the endogenous antioxidants (CAT, GSH, SOD). Moreover, E Se tea extracts ameliorated inflammation by restraining the activation of NF-κB, consequently releasing the expression of proinflammatory cytokines (TNF-α, IL-6, IL-1β, COX-2 and iNOS). Subsequently, E Se tea extracts reduced hepatocyte apoptosis by increasing capase-9, caspase-3 and Bax protein expression but decreasing Bcl-2 protein expression. Furthermore, E Se tea extracts improved metabolism imbalance by stimulating AMPK/SREBP1/FAS and PPAR-α/CPT1 signaling pathway by regulating lipid metabolism parameters (TC, TG, HDL-C, LHD-C). Furthermore, molecular docking results indicated that 7 chemical constituents of E Se tea extracts had strong docking affinity with 4 key target proteins (AMPK, PPAR-α, NF-кB and Caspase-9).

CONCLUSION

E Se tea ameliorated AFLD through ameliorating inflammatory response, apoptosis, and lipid metabolism imbalance.

The Beneficial Effects of Natural Extracts and Bioactive Compounds on the Gut-Liver Axis: A Promising Intervention for Alcoholic Liver Disease

Alcoholic liver disease (ALD) is a major cause of morbidity and mortality worldwide. It can cause fatty liver (steatosis), steatohepatitis, fibrosis, cirrhosis, and liver cancer. Alcohol consumption can also disturb the composition of gut microbiota, increasing the composition of harmful microbes and decreasing beneficial ones. Restoring eubiosis or preventing dysbiosis after alcohol consumption is an important strategy in treating ALD. Plant natural products and polyphenolic compounds exert beneficial effects on several metabolic disorders associated with ALD. Natural products and related phytochemicals act through multiple pathways, such as modulating gut microbiota, improving redox stress, and anti-inflammation. In the present review article, we gather information on natural extract and bioactive compounds on the gut-liver axis for the possible treatment of ALD. Supplementation with natural extracts and bioactive compounds promoted the intestinal tight junction, protected against the alcohol-induced gut leakiness and inflammation, and reduced endotoxemia in alcohol-exposed animals. Taken together, natural extracts and bioactive compounds have strong potential against ALD; however, further clinical studies are still needed.

Unraveling the phase behavior of cricket protein isolate and alginate in aqueous solution

The associative phase behavior of cricket protein isolate (CPI) and sodium alginate (AL) in aqueous solutions was explored using turbidimetry, methylene blue spectroscopy, zeta potentiometry, dynamic light scattering, and confocal microscopy as a function of pH, biopolymer ratio, total biopolymer concentration (C_T), and ionic strength. When both biopolymers had net-negative charges, soluble complexes formed between pH 6.0 and 8.0, however when both biopolymers had opposing net charges, insoluble complexes formed as complex coacervates below pH 5.5, defined as pH_φ1, followed by precipitates below another critical pH 3.0 (pH_p). Increasing the CPI:AL weight ratio or C_T facilitated complex formation, and the addition of salts (NaCl/KCl) had a salt-enhancement and salt-reduction impact at low and high salt concentrations, respectively. Ionic interactions between oppositely charged CPI and AL were mainly responsible for the formation of their insoluble complexes, while hydrogen bonding and hydrophobic interactions also played significant roles.

Gryllus bimaculatus De Geer hydrolysates alleviate lipid accumulation, inflammation, and endoplasmic reticulum stress in palmitic acid-treated human hepatoma G2 cells

ETHNOPHARMACOLOGICAL RELEVANCE

Nonalcoholic fatty liver disease (NAFLD) is one of the most common hepatic diseases closely intertwined with saturated fatty acids intake. Therefore, various studies are being conducted to find natural substances to prevent either the onset or progression of NAFLD. According to traditional medicinal literature, it has been reported that Gryllus bimaculatus De Geer (GB) has systemic detoxifying activity; however, the preventive effects of GB on NAFLD have not been elucidated to date.

AIM OF STUDY

To evaluate the potential of GB as a material for the mitigation of NAFLD, we investigated the effects of GB hydrolysates on the hepatic lipid accumulation, inflammation, and endoplasmic reticulum (ER) stress in human hepatoma G2 (Hep G2) cells treated with palmitic acid (PA).

METHODS

Steamed and dried GB was defatted, pulverized, and then lyophilized following hydrolyzation using Neutrase® (GB-N) or Flavourzyme® (GB-F). Hep G2 cells were incubated with GB-N or GB-F at various concentrations (0, 0.25, 0.5, and 1 mg/mL) for 24 h, and then PA was treated for another 24 h.

RESULTS

The GB-N and GB-F significantly prevented the PA-induced intracellular lipid accumulation in the human liver cells (p < 0.05). Moreover, the GB-N and GB-F increased the hepatic cellular viability against the PA-treatment (p < 0.05). In addition, the GB-N and GB-F significantly ameliorated the PA-inducible proinflammatory cytokines mRNA expression, such as tumor necrosis factor-α and interleukin-1β, compared to the PA-treated hepatic cells (p < 0.05). Furthermore, the GB-N and GB-F inhibited the PA-inducible lipogenic mRNA expression, such as fatty acid synthase, sterol regulatory element-binding protein 1c, and peroxisome proliferator-activated receptor-γ (p < 0.05). Moreover, the GB-N and GB-F alleviated the ER stress-related mRNA expression, such as glucose regulatory protein 78 and X-box binding protein increased in PA-treated cells (p < 0.05).

CONCLUSIONS

These results indicate that GB-N and GB-F could be used as materials to prevent the NAFLD onset or progression with alleviating hepatic lipid accumulation, inflammation, and ER stress.

Evaluation of the Immunological Activity of Gryllus bimaculatus Water Extract

Edible insects are commonly consumed across the world because of their size, availability, and nutritional benefits. They have also been recommended as a potential solution to food shortage because of their high nutritional value. In this study, we demonstrated the immunological effects of Gryllus bimaculatus on RAW 264.7 cells and splenocytes obtained from mouse. This is the first study to evaluate the immunological effects of G. bimaculatus water extract. Innate and adaptive immunity were evaluated and measured in RAW 264.7 cells and/or mouse splenocytes using a cell viability assay; changes in cytokine abundance, nitric oxide production, and cell surface molecule abundance were determined using flow cytometry; and western blotting analysis was performed for various immune signaling pathways. G. bimaculatus water extract showed no cytotoxicity in cells, and the results suggest that treatment with G. bimaculatus water extract can induce macrophage activation through mitogen-activated protein kinase and nuclear factor-κB signaling, induction of proinflammatory cytokines [interleukin (IL)-6, IL-1β, and tumor necrosis factor-α] and activation of the expression of cell surface molecules [cluster of differentiation (CD)80, CD86, major histocompatibility complex (MHC) class I, and MHC class II]. Treatment with G. bimaculatus water extract increased the production of cytokines (IL-2, IL-4, and interferon-γ) in splenocytes. The results indicate that G. bimaculatus water extract can regulate innate and adaptive immunity via modulation macrophages and splenocytes activation and can serve as an immunological agent. We inferred that G. bimaculatus is a safe and efficient natural material that enhances immunological activity.

Road to The Red Carpet of Edible Crickets through Integration into the Human Food Chain with Biofunctions and Sustainability: A Review

The Food and Agriculture Organization of the United Nations (FAO) estimates that more than 500 million people, especially in Asia and Africa, are suffering from malnutrition. Recently, livestock farming has increased to supply high-quality protein, with consequent impact on the global environment. Alternative food sources with high nutritive values that can substitute livestock demands are urgently required. Recently, edible crickets have been promoted by the FAO to ameliorate the food crisis. In this review, the distribution, nutritive values, health-promoting properties (antioxidant, anti-inflammatory, anti-diabetic and anti-obesity), safety, allergenicity as well as the potential hazards and risks for human consumption are summarized. Cricket farming may help to realize the United Nations sustainable development goal No. 2 Zero Hunger. The sustainability of cricket farming is also discussed in comparison with other livestock. The findings imply that edible crickets are safe for daily intake as a healthy alternative diet due to their high protein content and health-promoting properties. Appropriate use of edible crickets in the food and nutraceutical industries represents a global business potential. However, people who are allergic to shellfish should pay attention on cricket allergy. Thus, the objective of this review was to present in-depth and up-to-date information on edible crickets to advocate and enhance public perception of cricket-based food.

Evaluation of Anti-Cancer Activity of Gryllus bimaculatus Water Extract on Non-Small Cancer Lung Cell via Apoptosis

Gryllus bimaculatus, traditionally used in oriental medicine, demonstrates functional and pharmacological potential through demonstrating immunomodulatory, hepato-protective properties, anti-inflammatory, antioxidant, and neuroprotective effects. In this study, we examined the effect of G. bimaculatus on cell proliferation and apoptosis in lung cancer cells. This is the first study to examine the anti-cancer effects of G. bimaculatus extracts on non-small cell lung cancer. Frozen G. bimaculatus was obtained, homogenized, and dissolved in distilled water. Using a freeze dryer, samples were concentrated until almost all the water was removed, and extracts were diluted in solutions of phosphate buffered saline. Anti-cancer effects of extracts on human non-small cancer lung cells were estimated based on cell cytotoxicity, western blot, and flow cytometry, using lipopolysaccharides as a positive control. H460 and A549 human non-small cell cancer lung cells were treated with G. bimaculatus water extracts of various concentrations, with lipopolysaccharide used as a pos-itive control. The results showed that treatment with the extract for 24 or 48 h inhibited H460 proliferation, demonstrated by reduced cell numbers with morphological changes. Furthermore, flow cytometry analysis demonstrated that the extracts induced cell death on H460. However, extracts did not show cytotoxic effects on A549 cells. In conclusion, the extract induced apoptosis of lung cancer cells, possibly via caspase, Bcl-2 family signaling pathways. Therefore, G. bimaculatus water extracts are safe and efficient natural materials that may have great potential in the treatment of lung cancer.

Lactoferrin Alleviates Acute Alcoholic Liver Injury by Improving Redox-Stress Response Capacity in Female C57BL/6J Mice

Lactoferrin (Lf) can attenuate alcoholic liver injury (ALI) in male mice; however, the effects of Lf on acute ALI in female mice are still unknown. Female C57BL/6J mice were randomly divided into four groups and fed with different diets for 4 weeks: an AIN-93G diet for control (CON) and ethanol (EtOH) groups; an AIN-93G diet with 0.4 and 4% casein replaced by Lf for low-dose Lf (LLf) and high-dose Lf (HLf) groups. Acute ALI was induced by intragastric administration of ethanol (4.8 g/kgbw) every 12 h continuously for three times. HLf had obvious alleviating effects on acute ALI. Lf pretreatment did not affect hepatic alcohol metabolism key enzymes. Meanwhile, the ethanol-induced hepatic reactive oxygen species level increase was not ameliorated by Lf. Metabolomics and bioinformatics analysis results suggested an important role of redox-stress response capacity (RRC). Western blots showed HLf-promoted AKT and AMP-activated protein kinase activations and upregulated Nrf2 and LC3-II expressions, which was associated with RRC improvement. In summary, HLf could prevent acute ALI in female mice, and RRC likely played an important role.

Functional properties of edible insects: a systematic review

Consumption of edible insects has been widely suggested as an environmentally sustainable substitute for meat to reduce GHG emissions. However, the novel research field for edible insects rely on the content of bioactive ingredients and on the ability to induce a functional effect in humans. The goal of this manuscript was to review the available body of evidence on the properties of edible insects in modulating oxidative and inflammatory stress, platelet aggregation, lipid and glucose metabolism and weight control. A search for literature investigating the functional role of edible insects was carried out in the PUBMED database using specific keywords. A total of 55 studies, meeting inclusion criteria after screening, were divided on the basis of the experimental approach: in vitro studies, cellular models/ex vivo studies or in vivo studies. In the majority of the studies, insects demonstrated the ability to reduce oxidative stress, modulate antioxidant status, restore the impaired activity of antioxidant enzymes and reduce markers of oxidative damage. Edible insects displayed anti-inflammatory activity reducing cytokines and modulating specific transcription factors. Results from animal studies suggest that edible insects can modulate lipid and glucose metabolism. The limited number of studies focused on the assessment of anticoagulation activity of edible insects make it difficult to draw conclusions. More evidence from dietary intervention studies in humans is needed to support the promising evidence from in vitro and animal models about the functional role of edible insects consumption.

Digestibility of insect meals for Pacific white shrimp (Litopenaeus vannamei) and their performance for growth, feed utilization and immune responses

This study was conducted to examine digestibility of insect meals for Pacific white shrimp (Litopenaeus vannamei) and their utilization as fish meal substitutes. The tested insect meals were mealworm, silkworm, black soldier fly, rice grasshopper, two-spotted cricket, dynastid beetle and white-spotted flower chafer. Apparent digestibility coefficients of the tested insect meals were 83-89% for protein, 91-98% for lipid, 84-90% for energy, 77-81% for dry matter, 28-36% for chitin, 76-96% for amino acids and 89-93% for fatty acids. The amino acid availability of insect meals was high in taurine (93-96%), arginine (91-95%) and lysine (90-95%). Availability of fatty acids were 89-93% for saturated fatty acids, 90-93% for monounsaturated fatty acids and 88-93% for polyunsaturated fatty acids. For a feeding trial, a control diet was formulated using 27% tuna byproduct meal as a fish meal source and seven other diets were prepared replacing 10% tuna byproduct meal in the control diet with each insect meal. Triplicate groups of shrimp (initial body weight: 0.17 g) were fed the diets for 65 days. The growth performance was significantly improved when the shrimp were fed black soldier fly or dynastid beetle included diet. Dietary supplementation of insect meals significantly improved non-specific immune responses and antioxidant enzyme activity in the shrimp. These results indicate that the tested insect meals have high potentials to be used as a protein source that could replace fish meal in diets for the shrimp.

A Systematic Review on Viruses in Mass-Reared Edible Insect Species

Edible insects are expected to become an important nutrient source for animals and humans in the Western world in the near future. Only a few studies on viruses in edible insects with potential for industrial rearing have been published and concern only some edible insect species. Viral pathogens that can infect insects could be non-pathogenic, or pathogenic to the insects themselves, or to humans and animals. The objective of this systematic review is to provide an overview of the viruses detected in edible insects currently considered for use in food and/or feed in the European Union or appropriate for mass rearing, and to collect information on clinical symptoms in insects and on the vector role of insects themselves. Many different virus species have been detected in edible insect species showing promise for mass production systems. These viruses could be a risk for mass insect rearing systems causing acute high mortality, a drastic decline in growth in juvenile stages and in the reproductive performance of adults. Furthermore, some viruses could pose a risk to human and animal health where insects are used for food and feed.

Gryllus bimaculatus Extract Protects against Lipopolysaccharide-Derived Inflammatory Response in Human Colon Epithelial Caco-2 Cells

Simple Summary

Inflammatory bowel disease (IBD), a potentially life-threatening disease, is characterized by increased tight junction permeability and overproduction of proinflammatory cytokines. The long-term administration of recognized chemotherapeutic agents can cause serious potential side effects. As such, increasing attention has been paid to natural, low-toxicity products with anti-inflammatory properties for treating IBD. We assessed the potential utility of the edible cricket species Gryllus bimaculatus for anti-inflammatory and cytoprotective effects in the human epithelial cell line Caco-2, following treatment with an inflammatory lipopolysaccharide stimulus. We found that aqueous ethanolic G. bimaculatus extract (AE-GBE) treatment increased cell viability and significantly reduced inflammatory mediators. Moreover, AE-GBE significantly reduced inflammatory cytokine expression levels, intestinal epithelial permeability, and related tight junction protein expression levels. In conclusion, AE-GBE can protect epithelial cells from lipopolysaccharide-induced impaired barrier integrity by increasing tight junction proteins and preventing various inflammatory mediators. These results may be used to pursue further use of natural insect extracts in treating IBD.

Abstract

Increased tight junction permeability and overproduction of proinflammatory cytokines are crucial pathophysiological mechanisms in inflammatory bowel disease (IBD). This study evaluated anti-inflammatory effects of aqueous ethanolic Gryllus bimaculatus extract (AE-GBE) against intestinal permeability on lipopolysaccharide (LPS)-treated Caco-2 cells. Treatment with AE-GBE increased cell viability and significantly reduced inflammatory mediators such as nitric oxide and LPS-induced reactive oxidative stress. LPS increased the expression levels of iNOS, Cox-2, and 4-hydroxylnonenal; however, these levels were attenuated by AE-GBE treatment. Moreover, the mRNA and protein expression levels of the inflammatory cytokines TNFα, IL-6, IL-1β, and IFNγ were increased by LPS, but were significantly reduced by AE-GBE treatment. Intestinal epithelial permeability and the related expression of the proteins Zoula ocludence-1, occludin, and claudin-1 was increased by LPS treatment, and this effect was significantly reduced by AE-GBE treatment. The reduction in AMPK phosphorylation in LPS-treated Caco-2 cells was reversed in activation by co-treatment with AE-GBE. In conclusion, AE-GBE can protect epithelial cells from LPS-induced impaired barrier integrity by increasing tight junction proteins and preventing various inflammatory mediators. Thus, AE-GBE has the potential to improve inflammation-related diseases, including IBD, by inhibiting excessive production of inflammation-inducing mediators.

Effect of Defatting and Extraction Solvent on the Antioxidant and Pancreatic Lipase Inhibitory Activities of Extracts from Hermetia illucens and Tenebrio molitor

Simple Summary

The food industry is notably investing more resources on the production of nutritious, healthy, safe and sustainable products derived from edible insects. In this sense, natural extracts (or concentrated forms of compounds from natural sources) are usually food ingredients with added value for human health. This is due to their intrinsic beneficious biological activities; however, bioactive extracts from edible insects have been scarcely explored. Due to that and considering that the bioactivities of extracts might be conditioned by parameters of the technological process, we assessed how different extraction conditions, such as the defatting of the raw insect flours or the extraction solvents employed, affected two bioactivities of the resulting extracts from insects: the blocking of the digestion of fats from the diet by evaluating the inhibition of the responsible enzyme (pancreatic lipase), as well as their antioxidant activity. T. molitor and H. illucens were used, as they are two of the most known edible species for both feed and food. We observed a multibioactivity for all the extracts. Both tested processing factors differentially modulated the bioactivity of extracts from both species. We also analysed the composition of the H. illucens extracts and detected amino acids, lipids, carbohydrates, sterols and organic acids.

Abstract

The production of specific insect extracts with bioactive properties for human health is an emerging and innovative field for the edible insects industry, but there are unexplored extraction factors that might modulate the bioactivity of the extracts. Ultrasound-assisted extracts from T. molitor and H. illucens were produced. Effects of defatting pre-treatment and extraction solvent were evaluated on extraction yield, antioxidant activity and pancreatic lipase inhibitory effect. Chemical characterisation of defatted extracts from H. illucens was performed by GC-MS-FID. Non-defatted extracts showed higher extraction yields. Defatted extracts had similar extraction yields (around 3%). Defatted extracts had higher antioxidant activity, T. molitor being stronger than H. illucens. Antioxidant activity of T. molitor methanol extract was higher than the rest of solvents. Aqueous ethanol improved the antioxidant activity of H. illucens extracts. All extracts inhibited lipase, but no significant effect of defatting and solvent was observed for T. molitor. A significant higher inhibitory activity was observed for H. illucens, the strongest being defatted 100% and 70% ethanol H. illucens extracts. H. illucens extracts contained free amino acids and disaccharides, together with minor fractions of lipids, sterols and organic acids. These results evidence the potential of extracts obtained from edible insects as antioxidants and inhibitors of the pancreatic lipase, a simultaneous multibioactivity that might be favoured by the defatting pre-treatment of the samples and the solvent of extraction.

Effect of Three Defatting Solvents on the Techno-Functional Properties of an Edible Insect (Gryllus bimaculatus) Protein Concentrate

Edible insects have received global attention as an alternative protein-rich food. However, their structural characteristics make them difficult to digest. To overcome this obstacle, we assessed the techno-functional properties of three protein concentrates from the cricket Gryllus bimaculatus. Freeze-dried G. bimaculatus powder was defatted using ethanol, hexene, or acetone as solvents, and the techno-functional properties (protein solubility, water and oil holding capacity, foaming properties, emulsion capacity, and gel formation) of the protein concentrates were determined. Freeze-dried G. bimaculatus powder comprised approximately 17.3% crude fat and 51.3% crude protein based on dry weight. Ethanol was the most effective solvent for reducing the fat content (from 17.30% to 0.73%) and increasing the protein content (from 51.3% to 62.5%) of the concentrate. Techno-functionality properties drastically differed according to the defatting solvent used and foaming properties were most affected. Thus, the techno-functional and whole properties must be considered for proper application of edible insects to achieve global food sustainability.

Ellagic Acid Prevents Binge Alcohol-Induced Leaky Gut and Liver Injury through Inhibiting Gut Dysbiosis and Oxidative Stress

Alcoholic liver disease (ALD) is a major liver disease worldwide and can range from simple steatosis or inflammation to fibrosis/cirrhosis, possibly through leaky gut and systemic endotoxemia. Many patients with alcoholic steatohepatitis (ASH) die within 60 days after clinical diagnosis due to the lack of an approved drug, and thus, synthetic and/or dietary agents to prevent ASH and premature deaths are urgently needed. We recently reported that a pharmacologically high dose of pomegranate extract prevented binge alcohol-induced gut leakiness and hepatic inflammation by suppressing oxidative and nitrative stress. Herein, we investigate whether a dietary antioxidant ellagic acid (EA) contained in many fruits, including pomegranate and vegetables, can protect against binge alcohol-induced leaky gut, endotoxemia, and liver inflammation. Pretreatment with a physiologically-relevant dose of EA for 14 days significantly reduced the binge alcohol-induced gut barrier dysfunction, endotoxemia, and inflammatory liver injury in mice by inhibiting gut dysbiosis and the elevated oxidative stress and apoptosis marker proteins. Pretreatment with EA significantly prevented the decreased amounts of gut tight junction/adherent junction proteins and the elevated gut leakiness in alcohol-exposed mice. Taken together, our results suggest that EA could be used as a dietary supplement for alcoholic hepatitis patients.

Insights into the genomic evolution of insects from cricket genomes

Most of our knowledge of insect genomes comes from Holometabolous species, which undergo complete metamorphosis and have genomes typically under 2 Gb with little signs of DNA methylation. In contrast, Hemimetabolous insects undergo the presumed ancestral process of incomplete metamorphosis, and have larger genomes with high levels of DNA methylation. Hemimetabolous species from the Orthopteran order (grasshoppers and crickets) have some of the largest known insect genomes. What drives the evolution of these unusual insect genome sizes, remains unknown. Here we report the sequencing, assembly and annotation of the 1.66-Gb genome of the Mediterranean field cricket Gryllus bimaculatus, and the annotation of the 1.60-Gb genome of the Hawaiian cricket Laupala kohalensis. We compare these two cricket genomes with those of 14 additional insects and find evidence that hemimetabolous genomes expanded due to transposable element activity. Based on the ratio of observed to expected CpG sites, we find higher conservation and stronger purifying selection of methylated genes than non-methylated genes. Finally, our analysis suggests an expansion of the pickpocket class V gene family in crickets, which we speculate might play a role in the evolution of cricket courtship, including their characteristic chirping.

Ylla, Extavour et al. use genomic data from crickets to investigate the evolution of large genome sizes and DNA methylation events in insects. Their findings indicate that transposable element activity drove genome expansion in hemimetabolous insects, such as crickets and grasshoppers, and that DNA methylation is predominant in conserved genes.

Anti-Apoptotic Role of Sanhuang Xiexin Decoction and Anisodamine in Endotoxemia

Endotoxemia is characterized by initial uncontrollable inflammation, terminal immune paralysis, significant cell apoptosis and tissue injury, which can aggravate or induce multiple diseases and become one of the complications of many diseases. Therefore, anti-inflammatory and anti-apoptotic therapy is a valuable strategy for the treatment of endotoxemia-induced tissue injury. Traditional Chinese medicine exhibits great advantages in the treatment of endotoxemia. In this review, we have analyzed and summarized the active ingredients and their metabolites of Sanhuang Xiexin Decoction, a famous formula in endotoxemia therapy. We then have summarized the mechanisms of Sanhuang Xiexin Decoction against endotoxemia and its mediated tissue injury. Furthermore, silico strategy was used to evaluate the anti-apoptotic mechanism of anisodamine, a well-known natural product that widely used to improve survival in patients with septic shock. Finally, we also have summarized other anti-apoptotic natural products as well as their therapeutic effects on endotoxemia and its mediated tissue injury.

Translational Approaches with Antioxidant Phytochemicals against Alcohol-Mediated Oxidative Stress, Gut Dysbiosis, Intestinal Barrier Dysfunction, and Fatty Liver Disease

Emerging data demonstrate the important roles of altered gut microbiomes (dysbiosis) in many disease states in the peripheral tissues and the central nervous system. Gut dysbiosis with decreased ratios of Bacteroidetes/Firmicutes and other changes are reported to be caused by many disease states and various environmental factors, such as ethanol (e.g., alcohol drinking), Western-style high-fat diets, high fructose, etc. It is also caused by genetic factors, including genetic polymorphisms and epigenetic changes in different individuals. Gut dysbiosis, impaired intestinal barrier function, and elevated serum endotoxin levels can be observed in human patients and/or experimental rodent models exposed to these factors or with certain disease states. However, gut dysbiosis and leaky gut can be normalized through lifestyle alterations such as increased consumption of healthy diets with various fruits and vegetables containing many different kinds of antioxidant phytochemicals. In this review, we describe the mechanisms of gut dysbiosis, leaky gut, endotoxemia, and fatty liver disease with a specific focus on the alcohol-associated pathways. We also mention translational approaches by discussing the benefits of many antioxidant phytochemicals and/or their metabolites against alcohol-mediated oxidative stress, gut dysbiosis, intestinal barrier dysfunction, and fatty liver disease.

Dietary Modulation of Oxidative Stress From Edible Insects: A Mini-Review

Edible insects are proposed as a nutritious and environmentally sustainable alternative source to animal proteins, due to their numerous advantages in terms of reduced ecological impact and high nutritional value. However, the novelty for edible insects relies on the content of bioactive ingredients potentially able to induce a functional effect in the body. The present review summarizes the main findings on the antioxidant properties of edible insects available in the literature. A total of 30 studies involving animals, cell cultures, or in vitro experimental studies evaluating the antioxidant effect of edible insects are presented in this work. When the antioxidant activity was investigated, using a wide variety of in vitro tests and in cellular models, positive results were shown. Dietary supplementation with edible insects was also able to counteract dietary oxidative stress in animal models, restoring the balance of antioxidant enzymes and reducing the formation of oxidation damage markers. On the basis of the reviewed evidences, edible insects might represent a source of novel redox ingredients at low ecological impact able to modulate oxidative stress. However, due to the fact that majority of these evidences have been obtained in vitro and in cellular and animal models, dietary intervention trials are needed to assess the efficacy of edible insect consumption to modulate redox status in humans.

Gryllus bimaculatus extract protects against lipopolysaccharide and palmitate-induced production of proinflammatory cytokines and inflammasome formation

Inflammation and the inflammasome complex formation are associated with numerous diseases, and palmitates or lipopolysaccharides (LPS) have been identified as potential links between these disorders. Recently, edible insects such as the Gryllus bimaculatus (GB) and the larva of Tenebrio molitor have emerged as alternative food sources. In the present study, the effect of GB on LPS- or palmitate-induced production of inflammatory cytokines, the formation of the inflammasome complex, reactive oxygen species (ROS) generation, endoplasmic reticulum (ER) stress and cell death was investigated in RAW264.7 cells. The results revealed that GB extract downregulated the production of inflammatory cytokines (such as TNF-α, IL-1β and IL-6). Since the role of the MAP kinase and NF-κB signalling pathways in the production of inflammatory cytokines is well established, the translocation of p65 into the nucleus and the phosphorylation of IκB and MAP kinases were further examined. Both these processes were upregulated following LPS and palmitate treatment, but they were inhibited by the GB extract. Moreover, GB extract decreased LPS/palmitate-induced inflammasome complex formation (assessed via analysing the levels of the apoptosis-associated speck-like protein containing a caspase-recruitment domain, NOD-like receptor family pyrin domain containing 3, cleaved caspase-1 and IL-1β), the generation of ROS, ER stress and cell death. Treatment with SB203580 (a p38 inhibitor), SP600125 (a JNK inhibitor) and pyrrolidinedithiocarbamate ammonium (an NF-κB inhibitor) decreased the production of inflammatory cytokines, as well as helped in the recovery of LPS/palmitate-induced cell death. Overall, GB extract served an inhibitory role in LPS/palmitate-induced inflammation via inhibiting the MAP kinase and NF-κB signalling pathways, inflammasome complex formation, ROS generation, ER stress and cell death.

Edible Crickets (Orthoptera) Around the World: Distribution, Nutritional Value, and Other Benefits-A Review

Edible crickets are among the praised insects that are gaining recognition as human food and livestock feed with a potential of contributing to food security and reduction of malnutrition. Globally, the sustainable use of crickets as food or feed is undermined by lack of information on the number of the edible crickets, the country where they are consumed, and the developmental stages consumed. Furthermore, lack of data on their nutritional content and the potential risks to potential consumers limits their consumption or inclusion into other food sources. We reviewed published literature on edible cricket species, countries where they are consumed, and the stage at which they are consumed. We further reviewed information on their nutritional content, the safety of cricket consumption, and the sensory qualities of the edible crickets. We also looked at other benefits derived from the crickets, which include ethnomedicine, livestock feed, pest management strategies, contribution to economic development, and livelihood improvement, particularly in terms of use as food preservatives and use within music, sports, and cultural entomology. Lastly, we reviewed information on the farming of edible crickets. In this review, we report over 60 cricket species that are consumed in 49 countries globally. Nutritionally, crickets are reported to be rich in proteins, ranging from 55 to 73%, and lipids, which range from 4.30 to 33.44% of dry matter. The reported amount of polyunsaturated fatty acids (PUFA) is 58% of the total fatty acids. Edible crickets contain an appreciable amount of macro- and micro-mineral elements such as calcium, potassium, magnesium, phosphorus, sodium, iron, zinc, manganese, and copper. Also, the crickets are rich in the required amount of vitamins such as B group vitamins and vitamins A, C, D, E, and K. Overall, the cricket species examined in this review are safe to be consumed, and they display high proximate content that can replace plant and livestock products. The crickets play valuable roles in contributing to the economies of many countries and livelihoods, and they have medicinal and social benefits. This review is expected to promote greater recognition of crickets as a source of food, feed, and other benefits in the world and encourage up-scaling by farming them for sustainable utilization.

Gui-A-Gra Attenuates Testicular Dysfunction in Varicocele-Induced Rats via Oxidative Stress, ER Stress and Mitochondrial Apoptosis Pathway

Gui-A-Gra, a commercial insect powder from Gryllus bimaculatus, is registered as an edible insect by the Korean food and drug administration. The aim of this study was to investigate the effect of Gui-A-Gra on testicular damage induced by experimental left varicocele in male Sprague Dawley rats. A total of 72 rats were randomly divided into the following six groups (12 rats in each group): a normal control group (CTR), a group administrated with Gui-A-Gra 1.63 gm/kg (G1.63), a group administrated with Gui-A-Gra 6.5 gm/kg (G6.5), a varicocele (VC)-induced control group (VC), a VC-induced group administrated with Gui-A-Gra 1.63 gm/kg (VC + G1.63), and a VC-induced group administrated with Gui-A-Gra 6.5 gm/kg (VC + G6.5). Rats were administrated 1.63 or 6.5 gm/kg Gui-A-Gra once daily for 42 days. Indicators of sperm parameters, histopathology, reproductive hormones, oxidative stress, endoplasmic reticulum (ER) stress, inflammation, and mitochondrial apoptosis were analyzed to evaluate effects of Gui-A-Gra on VC-induced testicular dysfunction. Gui-A-Gra administration to VC-induced rats significantly (p < 0.05) increased sperm count and sperm motility, Johnsen score, spermatogenic cell density, serum testosterone, testicular superoxide dismutase (SOD), glutathione peroxidase (GPx), catalase, GPx4, and steroidogenic acute regulatory protein (StAR) level. Moreover, pretreatment with Gui-A-Gra significantly (p < 0.05) decreased terminal deoxynucleotidyl transferase-mediated dUTP nick-end labeling (TUNEL) positive cells/tubules, serum luteinizing hormone (LH), serum follicle-stimulating hormone (FSH), testicular tumor necrosis factor-α (TNF-α), interleukin-6 (IL-6), malondialdehyde (MDA), reactive oxygen species (ROS)/reactive nitrogen species (RNS) level, glucose-regulated protein-78 (Grp-78), phosphorylated c-Jun-N-terminal kinase (p-JNK), phosphorylated inositol-requiring transmembrane kinase/endoribonuclease 1α (p-IRE1α), cleaved caspase-3, and BCL2 associated X protein: B-cell lymphoma 2 (Bax: Bcl2) ratio in VC rats. These results suggest that protective effects of Gui-A-Gra on VC-induced testicular injury might be due to its antioxidant, anti-inflammatory, and androgenic activities that might be mediated via crosstalk of oxidative stress, ER stress, and mitochondrial apoptosis pathway.

Natural Product-Based Nanomedicine in Treatment of Inflammatory Bowel Disease

: Many synthetic drugs and monoclonal antibodies are currently in use to treat Inflammatory Bowel Disease (IBD). However, they all are implicated in causing severe side effects and long-term use results in many complications. Numerous in vitro and in vivo experiments demonstrate that phytochemicals and natural macromolecules from plants and animals reduce IBD-related complications with encouraging results. Additionally, many of them modify enzymatic activity, alleviate oxidative stress, and downregulate pro-inflammatory transcriptional factors and cytokine secretion. Translational significance of natural nanomedicine and strategies to investigate future natural product-based nanomedicine is discussed. Our focus in this review is to summarize the use of phytochemicals and macromolecules encapsulated in nanoparticles for the treatment of IBD and IBD-associated colorectal cancer.

Defatted Tenebrio molitor Larva Fermentation Extract Modifies Steatosis, Inflammation and Intestinal Microflora in Chronic Alcohol-Fed Rats

This study examined the effects of defatted mealworm fermentation extract (MWF) on alcoholic liver injury in rats. The rats were fed either a Lieber-DeCarli control (Con) or alcohol liquid diet (EtOH). The alcohol-fed rats were administered MWF (50, 100, or 200 mg/kg/day) and silymarin (200 mg/kg/day) orally for eight weeks. MWF prevented alcohol-induced hepatocellular damage by decreasing their serum aspartate transaminase, alanine transaminase, and gamma-glutamyl transpeptidase levels significantly compared to the EtOH group. MWF effectively reduced the relative hepatic weight, lipid contents, and fat deposition, along with the down-regulation of transcriptional factors and genes involved in lipogenesis compared to the EtOH group. It also enhanced the antioxidant defense system by elevating the glutathione level and glutathione reductase activity. MWF attenuated the alcohol-induced inflammatory response by down-regulating hepatic inflammation-associated proteins expression, such as phosphorylated-inhibitor of nuclear factor-kappa B-alpha and tumor necrosis factor-alpha, in chronic alcohol-fed rats. Furthermore, sequencing analysis in the colonic microbiota showed that MWF tended to increase Lactobacillus johnsonii reduced by chronic alcohol consumption. These findings suggest that MWF can attenuate alcoholic liver injury by regulating the lipogenic and inflammatory pathway and antioxidant defense system, as well as by partially altering the microbial composition.

Fermented Edible Insects for Promoting Food Security in Africa

Efforts to attain sustainable nutritional diets in sub-Saharan Africa (SSA) are still below par. The continent is envisaged to face more impending food crises. This review presents an overview of common edible insects in Africa, their nutritional composition, health benefits and utilization in connection with fermentation to enrich the inherent composition of insect-based products and offer foods related to existing and generally preferred culinary practice. Attempts to explore fermentation treatments involving insects showed fermentation affected secondary metabolites to induce antimicrobial, nutritional and therapeutic properties. Available value-added fermented edible insect products like paste, powder, sauces, and insect containing fermented foods have been developed with potential for more. Novel fermented edible insect-based products could effectively fit in the continent's food mix and therefore mitigate ongoing food insecurity, as well as to balance nutrition with health risk concerns limiting edible insects' product acceptability in SSA.

28-day repeated oral dose toxicity study of an aqueous extract of Gryllus bimaculatus in sprague-dawley rat

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Gryllus bimaculatus, edible insects, is the best alternative food source.

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Evaluation of Gryllus bimaculatus extracts with water in Sprague Dawley rats for its safety.

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No Observed Adverse Effect Level for Gryllus bimaculatus is considered to be 3000 mg/kg in rats.

This study was performed to demonstrate a No Observed Adverse Effect Level (NOAEL) for an aqueous extract of Gryllus bimaculatus. According to other studies, using dried material or extract with ethanol or methanol determined a NOAEL dose of 1000 mg/kg or 5000 mg/kg in rats. Therefore, the Gryllus bimaculatus groups were administered orally at doses of 0, 1000, 2000, and 3000 mg/kg for four weeks. Two-week recovery groups were administered at doses of 0, and 3000 mg/kg. During administration and recovery period, the animals were observed for clinical signs, change of body weight, food consumption, hematology, and clinical chemistry. Rats in each group were periodically sacrificed, and organs were weighed and examined histologically. No difference arose between any of the dosage groups and the control group in clinical signs, histopathological examination, hematology, or clinical chemistry. In conclusion, 3000 mg/kg is a NOAEL dose for Gryllus bimaculatus extracts in Sprague Dawley rats.

Novel hepatoprotective peptides derived from protein hydrolysates of mealworm (Tenebrio molitor)

In the present study, we hypothesized that protein hydrolysates of mealworm (Tenebrio molitor) which is known to exert significant scavenging activity toward reactive oxygen species (ROS) might protect liver cells against ROS-induced cytotoxicity. Therefore, hepatoprotective effects of protein hydrolysates of mealworm and their underlying mechanisms were investigated in AML12 mouse liver cells and the responsible peptides were further identified. Pretreatment with the mealworm alcalase hydrolysate (MAH; <1 kDa) showed the highest protective effect against H₂O₂-induced cytotoxicity in AML12 cells among three mealworm hydrolysates produced by different proteases (alcalase, flavourzyme, and neutrase). Further mechanistic studies demonstrated that MAH reduces ROS levels through increasing NF-E2-related factor 2-mediated expression of catalase, heme oxygenase-1, and genes involved in glutathione synthesis. Moreover, two novel hepatoprotective peptides, Ala-Lys-Lys-His-Lys-Glu and Leu-Glu, which shared similar mechanisms of action with MAH were identified. These results suggest that MAH and the two peptides represent potential sources of natural hepatoprotective agents.

Characterization, antioxidant activity, and inhibitory effect on pancreatic lipase of extracts from the edible insects Acheta domesticus and Tenebrio molitor

Extracts from the edible insects Acheta domesticus and Tenebrio molitor were obtained by ultrasound-assisted extraction (UAE) and pressurized-liquid extraction (PLE) using ethanol (E) or ethanol:water (E:W). Characterization by GC-MS was performed and total phenolic compounds (TPC), antioxidant activity (DPPH) and pancreatic lipase inhibitory capacity were assayed. Most extracts, mainly ethanolic extracts, predominantly presented lipids as free fatty acids, followed by aminoacids, organic acids, carbohydrates, hydrocarbons and sterols. The UAE-E:W extracts were different, being characterized by organic acids for A. domesticus, or aminoacids for T. molitor. All the extracts exhibited antioxidant activity, which correlated with TPC values, being the E:W extracts the most effective. All the extracts showed inhibitory activity of lipase, although those from T. molitor and extracted by PLE were the most effective. Therefore, bioactive insect extracts can be selectively obtained by advanced methods of extraction, being aqueous ethanol preferred for antioxidant activity and PLE for inhibitory lipase activity.

Beneficial role of insect-derived bioactive components against inflammation and its associated complications (colitis and arthritis) and cancer

Insect-based bioactive components are emerging as novel sources of drugs, effective against various diseases. Inflammation is considered to be an innate immune response developed by different organisms against foreign pathogens and cellular stress. However, repetitive elevated inflammation is considered to be responsible for development of many other diseases including colitis and arthritis. Due to the limited activities and side effects of non-steroidal anti-inflammatory drugs, researchers are continuously looking for alternative sources of drug molecules to alleviate the inflammatory related complications. Recently, insect-based bioactive components, such as venoms, haemocytes, cecropin A, papiliocin, N-acetyldopamine dimers, cecropin-TY1 peptide, cop A3 peptide, glycosaminoglycan, coprisin peptide, silk fibroin microparticles, and silk fibroin nanoparticles have been found to be active against different inflammatory mechanisms and associated diseases. Cancers, are some of the deadliest diseases, which are mainly treated by chemotherapy, radiation therapy and surgery. However, such treatments, mainly chemotherapy, is associated with enormous side effects. Therefore, as an alternative, less hazardous option, compounds from insects with anti-cancerous activity are being explored. Insect-derived compounds, such as cantharidin, norcantharidin, isocoumarin, plancyols A, plancypyrazine A, pancratistatin, narciclasine, and ungeremine, show potential anti-cancerous activity. In this review, we will be discussing the role of different potential drug molecules of insect origin with special emphasis on anti-inflammation and their association with health disorders and cancer.