In Vitro Antioxidant and Antihypertensive Activity of Edible Insects Flours (Mealworm and Grasshopper) Fermented with Lactococcus lactis Strains

Bioactive peptides derived from insect proteins: Preparation, biological activities, potential applications, and safety issues

Bioactive peptides are polypeptides with specific amino acid sequences that exhibit biological activities and health benefits. Insects have emerged as a sustainable source of proteins in human food and animal feed due to their efficient resource utilization, low environmental footprint, and good nutritional profile. Moreover, insect-derived bioactive peptides (IBPs) offer potential applications in functional foods and pharmaceuticals due to their antioxidant, antimicrobial, antihypertensive, anti-inflammatory, antidiabetic, and anti-obesity activities. In this article, the isolation, purification, and properties of IBPs are reviewed, as well as their potential health benefits, commercial applications, and safety. Despite the growing interest in incorporating IBPs into food products, challenges regarding consumer acceptance, safety, and regulations still persist. Thus, there is a pressing need for further research in this area, as well as clarification of the regulatory framework, before the full potential of insects as a sustainable source of bioactive peptides for human consumption can be realized.

Improvement of properties and olfactory attributes of isolated protein from edible insects by roasting

The characteristics of proteins extracted from two kinds of edible insects (Gryllus Bimaculatus and Tenebrio Molitor, for G.B and T.M, respectively) were compared after roasting at 180 °C for 15 min and 200 °C for 10 min, respectively. The amino acid content decreased by roasting, and the degree of decrease varied depending on the type of edible insect and roasting temperature. Antioxidant activity increased by 5.2-11.3% following roasting, with no significant differences by roasting temperature. The results of Infrared (IR) spectrum and gas chromatography (GC) analysis revealed that compounds contributing to a strong waxy scent and sour taste decreased, whereas those associated with aroma and floral scent increased as a result of roasting. In conclusion, roasting led to an enhancement in the olfactory characteristics of proteins extracted from edible insects, and roasting at 180 °C for 20 min for G.B and 200 °C for 15 min for T.M could be considered optimal.

Biotransformation of insect processing residues: Production of lactic acid bacterial biomass and associated partial removal of proteins from chitin

Processing of edible insects typically involves fractionating into high-value food ingredients, which results in by-products containing chitin and insoluble proteins. This study examined the effectiveness of lactic acid bacteria (LAB) in removing proteins from chitin in insect processing residues. Lesser mealworm processing residues were biologically treated for 48 and 120 h using LAB strains without added carbon sources. Results showed partial deproteinization, up to 29 % with Levilactobacillus brevis after 120 h. Most LAB grew up to 2 log10 colony-forming units/mL in the first 48 h. Confocal microscopy and Fourier-transform infrared spectra indicated that some protein remained attached to chitin. The molecular weight of solubilized proteins was affected by strain and time of incubation, with antioxidant activity increasing significantly after 120 h with Lacticaseibacillus paracasei. The biological treatment of insect processing streams can be a sustainable approach to producing high amounts of LAB biomass with subsequent protein solubilization and chitin release.

Anti-muscle atrophy effect of fermented Tenebrio molitor larvae extract by modulating the PI3K-Akt-mTOR/FoxO3α pathway in mice treated with dexamethasone

This study investigated the anti-sarcopenic effect of fermented Tenebrio molitor larvae (mealworms) extract (FME) in both dexamethasone (DEX)-treated C2C12 cells and mice. FME (100 µg/mL) increased the diameter of myotubes and inhibited the gene and protein expression of atrogin-1 compared to DEX- or non-fermented mealworms extract (ME)-treated C2C12 cells. Male C57BL/6N mice were divided into five groups: Normal Control (NC), DEX (10 mg/kg, intraperitoneal), and three groups of DEX+FME (100, 200, or 500 mg FME/kg/day, oral) for two weeks. FME at doses of 200 and 500 mg/kg effectively improved grip strength when compared to the DEX group. Histological analysis of the quadriceps muscle showed a larger muscle fiber size in the DEX+FME groups compared to DEX group. FME (200 and 500 mg/kg) significantly increased cross-sectional area of the muscle fiber compared to DEX group. FME (500 mg/kg) significantly decreased the ubiquitin, atrogin-1 and MuRF-1 protein levels, and increased levels of MHC and MyoG in DEX-treated mice. The puromycin labeling assay revealed that FME increased protein synthesis in DEX-induced muscle atrophy. The FME treatment demonstrated significant upregulation in phosphorylation levels, including mTOR, FoxO3α, Akt, and PI3K compared to DEX group. In conclusion, FME inhibited the increase in proteins associated with muscle atrophy, including, atrogin-1 and MuRF-1, by regulating the PI3K-Akt-FoxO3α pathway. FME improved the PI3K-Akt-mTOR signaling pathway, which was reduced by DEX. This study suggests that FME has the potential for use in sarcopenia therapy, possibly serving as a natural agent that counteracts the negative effects of DEX on muscle tissue.

Combined Analysis of Metabolomics and Biochemical Changes Reveals the Nutritional and Functional Characteristics of Red Palm Weevil Rhynchophus ferrugineus (Coleoptera: Curculionidae) Larvae at Different Developmental Stages

In this study, the changes in the conventional nutrient and mineral compositions as well as the metabolomics characteristics of the red palm weevil (RPW) Rhynchophus ferrugineus Olivier (Curculionidae: Coleoptera) larvae at early (EL), middle (ML) and old (OL) developmental stages were investigated. Results showed that the EL and ML had the highest content of protein (53.87 g/100 g dw) and fat (67.95 g/100 g), respectively, and three kinds of RPW larvae were all found to be rich in unsaturated fatty acids (52.17-53.12%), potassium (5707.12-15,865.04 mg/kg) and phosphorus (2123.87-7728.31 mg/kg). In addition, their protein contained 17 amino acids with the largest proportion of glutamate. A total of 424 metabolites mainly including lipids and lipid-like molecules, organic acids and their derivatives, organic heterocycle compounds, alkaloids and their derivatives, etc. were identified in the RPW larvae. There was a significant enrichment in the ABC transport, citrate cycle (TCA cycle), aminoacyl-tRNA biosynthesis, and mTOR signaling pathways as the larvae grow according to the analysis results of the metabolic pathways of differential metabolites. The water extract of EL exhibited relatively higher hydroxyl, 2,2-diphenyl-1-pyrroline hydrochloride (DPPH) and 2,2'-azobis (3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) radical-scavenging ability with the EC50 values of 1.12 mg/mL, 11.23 mg/mL, and 2.52 mg/mL, respectively. These results contribute to a better understanding of the compositional changes of the RPW larvae during its life cycle and provide a theoretical grounding for its deep processing and high-value utilization.

An overview of fermentation in the food industry - looking back from a new perspective

Fermentation is thought to be born in the Fertile Crescent, and since then, almost every culture has integrated fermented foods into their dietary habits. Originally used to preserve foods, fermentation is now applied to improve their physicochemical, sensory, nutritional, and safety attributes. Fermented dairy, alcoholic beverages like wine and beer, fermented vegetables, fruits, and meats are all highly valuable due to their increased storage stability, reduced risk of food poisoning, and enhanced flavor. Over the years, scientific research has associated the consumption of fermented products with improved health status. The fermentation process helps to break down compounds into more easily digestible forms. It also helps to reduce the amount of toxins and pathogens in food. Additionally, fermented foods contain probiotics, which are beneficial bacteria that help the body to digest food and absorb nutrients. In today's world, non-communicable diseases such as cardiovascular disease, type 2 diabetes, cancer, and allergies have increased. In this regard, scientific investigations have demonstrated that shifting to a diet that contains fermented foods can reduce the risk of non-communicable diseases. Moreover, in the last decade, there has been a growing interest in fermentation technology to valorize food waste into valuable by-products. Fermentation of various food wastes has resulted in the successful production of valuable by-products, including enzymes, pigments, and biofuels.

Legal situation and consumer acceptance of insects being eaten as human food in different nations across the world-A comprehensive review

Insect consumption is a traditional practice in many countries. Currently, the urgent need for ensuring food sustainability and the high pressure from degrading environment are urging food scientists to rethink the possibility of introducing edible insects as a promising food type. However, due to the lack of the standardized legislative rules and the adequate scientific data that demonstrate the safety of edible insects, many countries still consider it a grey area to introduce edible insects into food supply chains. In this review, we comprehensively reviewed the legal situation, consumer willingness, acceptance, and the knowledge on edible insect harvesting, processing as well as their safety concerns. We found that, despite the great advantage of introducing edible insects in food supply chains, the legal situation and consumer acceptance for edible insects are still unsatisfactory and vary considerably in different countries, which mostly depend on geographical locations and cultural backgrounds involving psychological, social, religious, and anthropological factors. Besides, the safety concern of edible insect consumption is still a major issue hurdling the promotion of edible insects, which is particularly concerning for countries with no practice in consuming insects. Fortunately, the situation is improving. So far, some commercial insect products like energy bars, burgers, and snack foods have emerged in the market. Furthermore, the European Union has also recently issued a specific item for regulating new foods, which is believed to establish an authorized procedure to promote insect-based foods and should be an important step for marketizing edible insects in the near future.

Neuroprotective effects of hydroponic ginseng fermented by Lactococcus lactis KC24 in oxidatively stressed SH-SY5Y cells

BACKGROUND

Panax ginseng Meyer, a traditional herb in Asia, contains bioactive compounds such as polyphenolic compounds, flavonoids, and ginsenosides. Furthermore, fermentation with probiotics can promote the biofunctional activities of ginseng. This study's object was to investigate the neuroprotective effect of hydroponic ginseng against hydrogen peroxide (H₂ O₂ )-induced cytotoxicity and its effect on the fermentation time.

RESULTS

Nonfermented hydroponic ginseng (HNF) was fermented with Lactococcus lactis KC24 at 37 °C for 12 h (H12F) or 24 h (H24F). As fermentation progressed, the content of ginsenosides Rd and F2 increased slightly. The viability of cells pretreated with H₂ O₂ -exposed nonfermented soil-cultivated ginseng (SNF), HNF, H12F, and H24F gradually improved. In addition, a similar cytotoxicity trend was observed for the level of lactate dehydrogenase released. Fermentation with L. lactis KC24 also enhanced the protective effect of HNF in all assays related to the neuroprotective pathway. In other words, superoxide dismutase and catalase messenger RNA (mRNA) expression levels were upregulated in H24F-treated cells. Similarly, H24F also upregulated the mRNA and protein expression of brain-derived neurotrophic factor to the highest observed concentration. Moreover, the Bax/Bcl-2 ratio was the lowest after H24F pretreatment in H₂ O₂ -induced SH-SY5Y cells. Attenuating the cytotoxicity in H₂ O₂ -induced SH-SY5Y cells, H24F markedly reduced caspase-3 and -9 mRNA expression and caspase-3 activity.

CONCLUSION

These results suggest that HNF exhibited higher neuroprotection than SNF, which was enhanced after fermentation. This study demonstrates that H12F and H24F can be potential ingredients for developing healthy functional foods and pharmaceutical materials. © 2023 Society of Chemical Industry.

The Review of Cooking, Drying, and Green Extraction Methods on General Nutritional Properties of Mealworms and Locusts

The processing of edible insects as an alternative source of nutrition may be a key driver in the development of a sustainable food and feed system. This review will study two industrial types of insects-mealworms and locusts-and summarize evidence related to the impact of processing on their micro- and macronutritional characteristics. The focus will be on their potential use as food for human consumption as opposed to animal feed. Literature has indicated that these two insects have the potential to provide protein and fat qualities comparable to or better than traditional mammalian sources. For example, mealworms-the larval form of the yellow mealworm beetlepossess a higher fat content, while adult locusts are rich in fibers, especially chitin. However, due to the different matrix and nutrient compositions, the processing of mealworms or locusts at a commercial scale needs to be tailored to minimize nutritional loss and maximize cost efficiency. The stages of preprocessing, cooking, drying, and extraction are the most critical control points for nutritional preservation. Thermal cooking applications such as microwave technology have demonstrated promising results, but the generation of heat may contribute to a certain nutritional loss. In an industrial context, drying using freeze dry is the preferred choice due to its uniformity, but it can be costly while increasing lipid peroxidation. During the extraction of nutrients, the use of green emerging technologies such as high hydrostatic pressure, pulsed electric field, and ultrasound may provide an alternative method to enhance nutrient preservation.

Graphical Abstract

Bioactive Peptide Discovery from Edible Insects for Potential Applications in Human Health and Agriculture

In the past decade, there has been fast-growing interest among researchers to discover bioactive peptides from edible insects and to evaluate their potential applications in the management of human, livestock, and plant health. This review summarizes current knowledge of insect-derived peptides and their potential role in tackling human health issues and solving agriculture problems by protecting crops and livestock against their pathogens. Numerous bioactive peptides have been identified from edible insect species, including peptides that were enzymatically liberated from insect proteins and endogenous peptides that occur naturally in insects. The peptides exhibited diverse bioactivities, encompassing antioxidant, anti-angiotensin-converting enzyme, anti-dipeptidyl peptidase-IV, anti-glucosidase, anti-lipase, anti-lipoxygenase, anti-cyclooxygenase, anti-obesity, and hepatoprotective activities. Such findings point to their potential contribution to solving human health problems related to inflammation, free radical damage, diabetes, hypertension, and liver damage, among others. Although most of the experiments were performed in vitro, evidence for the in vivo efficacy of some peptides is emerging. Evidence of the protective effects of insect-derived endogenous antimicrobial peptides in combating farm animal and plant pathogens is available. The ability of insect-derived endogenous neuropeptides to protect plants against herbivorous insects has been demonstrated as well. Nevertheless, the potency of peptides identified from insect protein hydrolysates in modulating livestock and plant health remains a knowledge gap to be filled.

Edible Insects an Alternative Nutritional Source of Bioactive Compounds: A Review

Edible insects have the potential to become one of the major future foods. In fact, they can be considered cheap, highly nutritious, and healthy food sources. International agencies, such as the Food and Agriculture Organization (FAO), have focused their attention on the consumption of edible insects, in particular, regarding their nutritional value and possible biological, toxicological, and allergenic risks, wishing the development of analytical methods to verify the authenticity, quality, and safety of insect-based products. Edible insects are rich in proteins, fats, fiber, vitamins, and minerals but also seem to contain large amounts of polyphenols able to have a key role in specific bioactivities. Therefore, this review is an overview of the potential of edible insects as a source of bioactive compounds, such as polyphenols, that can be a function of diet but also related to insect chemical defense. Currently, insect phenolic compounds have mostly been assayed for their antioxidant bioactivity; however, they also exert other activities, such as anti-inflammatory and anticancer activity, antityrosinase, antigenotoxic, and pancreatic lipase inhibitory activities.

Environmental effects of harvesting some Mexican wild edible insects: An overview

Most traditional edible insects are collected from the forest and agricultural fields, where they are considered pests. However, their importance goes beyond this. They also have an ecological role and potential to be an emerging alternative source of high-quality nutrients that can help satisfy the growing food demand for the human population. Agricultural insect pests are a healthy food source during the harvesting season in many tropical countries. In Mexico, wild insects such as chicatana (queen of flying leaf-cutter ant, Atta mexicana Smith, 1,858; Hymenoptera: Formicidae), chapulín (grasshopper, Pyrgomorphidae), chinicuil (agave red worm, Comadia redtenbacheri Hammerschmidt, 1,848: Lepidoptera, Cossidae), and meocuil (agave white worm, Aegiale hesperiaris Walker 1,856, Lepidoptera, Hesperiidae) are seasonally collected from the agricultural land and forest for food and medicine. Thus, their consumption might be regarded as support for biological plague control. However, in most countries (Mexico included), there is a lack of legislation about edible insects from harvesting to sacrifice and even their main safety aspects. So then, this research aims to provide an updated assessment of the potential use of agricultural pest insects as a sustainable alternative for food, considering current international legislative and ethical concerns about harvesting and consuming wild edible insects, focusing on some of the wild edible pest insects in Mexico.

Beyond Human Nutrition of Edible Insects: Health Benefits and Safety Aspects

Nowadays, edible insects are considered an outstanding source of nutrients, primarily because they contain high-quality protein, amino acids, and vitamins. Insects are considered a promising alternative protein source towards alleviating future global food shortage problems due to their production considered as being more sustainable by using less agricultural land and water, as well as releasing a smaller amount of greenhouse gas emissions. However, other important aspects to consider about the consumption of edible insects include their health benefits and some safety aspects, which has been relatively overlooked. In this sense, edible insects contain bioactive compounds that can provide diverse bioactivities, such as antioxidant, antihypertensive, anti-inflammatory, antimicrobial, and immunomodulatory with a positive impact on human health. On the other hand, edible insects are a nutrient-rich food that can provide a perfect growth medium for diverse microorganisms, as well as possess some anti-nutritive factors. These two main aspects could represent food safety concerns for consumers. In this context, recent scientific evidence indicates that preservation methods, mainly thermal treatments, utilized in the cooking or processing of edible insects decreased the microbial levels and anti-nutritive factors, which suggests that edible insects do not represent a critical biological risk to humans. Besides, edible insects could have a positive effect on gut microbiota, either by their pre-biotic effect or their antimicrobial activity towards pathogens. Thus, this review is focused on studies related to the health benefits of edible insects and their isolated components, as well as discussion about potential issues related to their microbial content and anti-nutritive factors; this review will provide a synopsis on whether edible insects may be considered safe for human consumption.

The Impact of Insect Flour on Sourdough Fermentation-Fatty Acids, Amino-Acids, Minerals and Volatile Profile

Acheta domesticus (L.1758) has been recently accepted by the European Union as a novel food, being the third insect that has been approved for human consumption. Nowadays, researchers' attention is focused on exploiting new protein sustainable sources, and, therefore, insect flour has gained more and more interest. Organic acids, fatty acids, amino acids, aroma volatile compounds, and minerals were analyzed through HPLC-RID (High-performance liquid chromatography), GC-MS (Gas chromatography-mass spectrometry), LC-MS (Liquid chromatography-mass spectrometry), ITEX/GC-MS and AAS (Atomic Absorption Spectrophotometry), respectively. Fermentation of the insect flour with Lactobacillus plantarum ATCC 8014 strain (Lp) leads to an increase in organic acids such as lactic, acetic, and oxalic, whilst citric acid decreases its value. SFA (saturated fatty acids) and MUFA (monosaturated fatty acids) groups were positively influenced by Lp fermentation; meanwhile, PUFA (polysaturated fatty acids) decreased during fermentation. A positive trend was observed for amino acids, aroma volatile content, and minerals enhancement during insect sourdough fermentation, mainly at 24 h of fermentation. Acheta domesticus (A. domesticus) sourdough fermentation represents a new tool that needs to be further exploited aiming to improve the nutritional qualities of the final products.

Edible insects, a valuable protein source from ancient to modern times

The current COVID-19 pandemic has demonstrated that we are not prepared to deal with food security amid unexpected situations; the FAO (Food and Agriculture Organization) has stipulated that the future of our food & agriculture looks challenging toward the year 2050; primarily in response to the fact that global population is expected to increase by 9 billion people by 2050. Although entomophagy has been practiced by humans for thousands of years, until recently, edible insects have gained special attention due to their high nutritional value (particularly their high protein and essential amino acid content) and lower environmental impact that could help alleviate the global food demand. Edible insects are classified into eight main orders belonging to Blattodea (cockroaches and termites), Coleoptera (beetles), Diptera (flies), Hemiptera (cicadas, stink bugs), Hymenoptera (bees, wasps, ants), Lepidoptera (butterflies, moths), Odonata (dragonflies), and Orthoptera (crickets, grasshoppers, locusts). Several traditional cooking (e.g., boiling, roasting, sun-drying) and processing technologies (e.g., pasteurization, enzymatic proteolysis, high pressure processing) have shown that it is feasible to prepare safe and nutritious insects and/or foods with insects. Nevertheless, challenges associated with consumers acceptance to eat insects, as well as potential presence of anti-nutritive factors and allergens, need to be carefully evaluated as the industry grows in the coming years. Foreseeing such food shortages during pandemics and future food security concerns, consumers, scientists, and the food industry need to consider the value of farming insects as promising protein sources.