Antimicrobial activity of lipids extracted from Hermetia illucens reared on different substrates.

As the problem of antimicrobial resistance is constantly increasing, there is a renewed interest in antimicrobial products derived from natural sources, particularly obtained from innovative and eco-friendly materials. Insect lipids, due to their fatty acid composition, can be classified as natural antimicrobial compounds. In order to assess the antibacterial efficacy of Hermetia illucens lipids, we extracted this component from the larval stage, fed on different substrates and we characterized it. Moreover, we analyzed the fatty acid composition of the feeding substrate, to determine if and how it could affect the antimicrobial activity of the lipid component. The antimicrobial activity was evaluated against Gram-positive Micrococcus flavus and Gram-negative bacteria Escherichia coli. Analyzing the fatty acid profiles of larval lipids that showed activity against the two bacterial strains, we detected significant differences for C4:0, C10:0, C16:1, C18:3 n3 (ALA), and C20:1. The strongest antimicrobial activity was verified against Micrococcus flavus by lipids extracted from larvae reared on strawberry, tangerine, and fresh manure substrates, with growth inhibition zones ranged from 1.38 to 1.51 mm, while only the rearing on manure showed the effect against Escherichia coli. Notably, the fatty acid profile of H. illucens seems to not be really influenced by the substrate fatty acid profile, except for C18:0 and C18:2 CIS n6 (LA). This implies that other factors, such as the rearing conditions, larval development stages, and other nutrients such as carbohydrates, affect the amount of fatty acids in insects. KEY POINTS: • Feeding substrates influence larval lipids and fatty acids (FA) • Generally, there is no direct correlation between substrate FAs and the same larvae FAs • Specific FAs influence more the antimicrobial effect of BSF lipids.

CGRP Antagonism and Ketogenic Diet in the Treatment of Migraine.

The study of migraine is based on the complexity of the pathology, both at the pathophysiological and epidemiological levels. Although it affects more than a billion people worldwide, it is often underestimated and underreported by patients. Migraine must not be confused with a simple headache; it is a serious and disabling disease that causes considerable limitations in the daily life of afflicted people, including social, work, and emotional effects. Therefore, it causes a daily state of suffering and discomfort. It is important to point out that this pathology not only has a decisive impact on the quality of life of those who suffer from it but also on their families and, more generally, on society as a whole. The clinical picture of migraine is complex, with debilitating unilateral or bilateral head pain, and is often associated with characteristic symptoms such as nausea, vomiting, photophobia, and phonophobia. Hormonal, environmental, psychological, dietary, or other factors can trigger it. The present review focuses on the analysis of the physiopathological and pharmacological aspects of migraine, up to the correct dietary approach, with specific nutritional interventions aimed at modulating the symptoms. Based on the symptoms that the patient experiences, targeted and specific therapy is chosen to reduce the frequency and severity of migraine attacks. Specifically, the role of calcitonin gene-related peptide (CGRP) in the pathogenesis of migraine is analyzed, along with the drugs that effectively target the corresponding receptor. Particularly, CGRP receptor antagonists (gepants) are very effective drugs in the treatment of migraine, given their high diffusion in the brain. Moreover, following a ketogenic diet for only one or two months has been demonstrated to reduce migraine attacks. In this review, we highlight the diverse facets of migraine, from its physiopathological and pharmacological aspects to prevention and therapy.

Exosomes and Signaling Nanovesicles from the Nanofiltration of Preconditioned Adipose Tissue with Skin-B® in Tissue Regeneration and Antiaging: A Clinical Study and Case Report.

Background and Objectives: This three-year clinical trial aimed to demonstrate that only the signaling vesicles produced by ADSCa, containing mRNA, microRNA, growth factors (GFs), and bioactive peptides, provide an advantage over classical therapy with adipose disaggregate to make the tissue regeneration technique safer due to the absence of interfering materials and cells, while being extremely minimally invasive. The infiltration of disaggregated adipose nanofat, defined by the Tonnard method, for the regeneration of the dermis and epidermis during physiological or pathological aging continues to be successfully used for the presence of numerous adult stem cells in suspension (ADSCa). An improvement in this method is the exclusion of fibrous shots and cellular debris from the nanofat to avoid inflammatory phenomena by microfiltration. Materials and Methods: A small amount of adipose tissue was extracted after surface anesthesia and disaggregated according to the Tonnard method. An initial microfiltration at 20/40 microns was performed to remove fibrous shots and cellular debris. The microfiltration was stabilized with a sterile solution containing hyaluronic acid and immediately ultrafiltered to a final size of 0.20 microns to exclude the cellular component and hyaluronic acid chains of different molecular weights. The suspension was then injected into the dermis using a mesotherapy technique with microinjections. Results: This study found that it is possible to extract signaling microvesicles using a simple ultrafiltration system. The Berardesca Scale, Numeric Rating Scale (NRS), and Modified Vancouver Scale (MVS) showed that it is possible to obtain excellent results with this technique. The ultrafiltrate can validly be used in a therapy involving injection into target tissues affected by chronic and photoaging with excellent results. Conclusions: This retrospective clinical evaluation study allowed us to consider the results obtained with this method for the treatment of dermal wrinkles and facial tissue furrows as excellent. The method is safe and an innovative regenerative therapy as a powerful and viable alternative to skin regeneration therapies, antiaging therapies, and chronic inflammatory diseases because it lacks the inflammatory component produced by cellular debris and fibrous sprouts and because it can exclude the mesenchymal cellular component by reducing multiple inflammatory cytokine levels.

Odorant binding proteins fromHermetia illucens: potential sensing elements for detecting volatile aldehydes involved in early stages of organic decomposition.

Organic decomposition processes, involving the breakdown of complex molecules such as carbohydrates, proteins and fats, release small chemicals known as volatile organic compounds (VOCs), smelly even at very low concentrations, but not all readily detectable by vertebrates. Many of these compounds are instead detected by insects, mostly by saprophytic species, for which long-range orientation towards organic decomposition matter is crucial. In the present work the detection of aldehydes, as an important measure of lipid oxidation, has been possible exploiting the molecular machinery underlying odour recognition inHermetia illucens(Diptera: Stratiomyidae). This voracious scavenger insect is of interest due to its outstanding capacity in bioconversion of organic waste, colonizing very diverse environments due to the ability of sensing a wide range of chemical compounds that influence the choice of substrates for ovideposition. A variety of soluble odorant binding proteins (OBPs) that may function as carriers of hydrophobic molecules from the air-water interface in the antenna of the insect to the receptors were identified, characterised and expressed. An OBP-based nanobiosensor prototype was realized using selected OBPs as sensing layers for the development of an array of quartz crystal microbalances (QCMs) for vapour phase detection of selected compounds at room temperature. QCMs coated with four recombinantH. illucensOBPs (HillOBPs) were exposed to a wide range of VOCs indicative of organic decomposition, showing a high sensitivity for the detection of three chemical compounds belonging to the class of aldehydes and one short-chain fatty acid. The possibility of using biomolecules capable of binding small ligands as reversible gas sensors has been confirmed, greatly expanding the state-of the-art in gas sensing technology.

Toward a spatially explicit analysis of land vulnerability to degradation: a country-level approach supporting policy strategies.

Vulnerability to land degradation in Mediterranean Europe increased substantially in the last decades because of the latent interplay of climate and land-use change, progressive soil deterioration, and rising human pressure. The present study provides a quantitative evaluation of the intrinsic change over time in the level of vulnerability to land degradation over a representative Mediterranean area (Italy) using a normative indicator, the percentage of land classified as 'critical' in total area. This indicator derives from a spatially explicit elaboration of the ESA (Environmental Sensitive Area) Index (ESAI), a standard methodology of land classification considering different levels of vulnerability to degradation at a particularly refined spatial scale (1 km2). This indicator was calculated over a relatively long time interval (1960-2010) and aggregated at the geographical scale of administrative regions in Italy, a relevant domain in the implementation of the National Action Plan (NAP) to combat desertification and the adoption of individual Regional Action Plans (RAP). A significant - but spatially heterogeneous - increase in 'critical' land was observed in Italy, leading to distinctive dynamics in northern/central regions and southern regions. Climate aridity and anthropogenic pressure leveraged the sudden vulnerability in some marginal land of Northern Italy - a region classified as unexposed to desertification risk - paralleling the levels observed in some districts of Southern Italy, an 'affected' region to desertification risk. These results suggest a re-thinking of mitigation policies proposed in the Italian NAP and a redesign of the RAPs toward place-specific adaptation measures, especially in the 'less exposed' Northern Italian region.

Structural and Functional Characterization of a Novel Recombinant Antimicrobial Peptide from Hermetia illucens.

Antibiotics are commonly used to treat pathogenic bacteria, but their prolonged use contributes to the development and spread of drug-resistant microorganisms raising the challenge to find new alternative drugs. Antimicrobial peptides (AMPs) are small/medium molecules ranging 10-60 residues synthesized by all living organisms and playing important roles in the defense systems. These features, together with the inability of microorganisms to develop resistance against the majority of AMPs, suggest that these molecules might represent effective alternatives to classical antibiotics. Because of their high biodiversity, with over one million described species, and their ability to live in hostile environments, insects represent the largest source of these molecules. However, production of insect AMPs in native forms is challenging. In this work we investigate a defensin-like antimicrobial peptide identified in the Hermetia illucens insect through a combination of transcriptomics and bioinformatics approaches. The C-15867 AMP was produced by recombinant DNA technology as a glutathione S-transferase (GST) fusion peptide and purified by affinity chromatography. The free peptide was then obtained by thrombin proteolysis and structurally characterized by mass spectrometry and circular dichroism analyses. The antibacterial activity of the C-15867 peptide was evaluated in vivo by determination of the minimum inhibitory concentration (MIC). Finally, crystal violet assays and SEM analyses suggested disruption of the cell membrane architecture and pore formation with leaking of cytosolic material.

Functional insights from the GC-poor genomes of two aphid parasitoids, Aphidius ervi and Lysiphlebus fabarum.

BACKGROUND: Parasitoid wasps have fascinating life cycles and play an important role in trophic networks, yet little is known about their genome content and function. Parasitoids that infect aphids are an important group with the potential for biological control. Their success depends on adapting to develop inside aphids and overcoming both host aphid defenses and their protective endosymbionts. RESULTS: We present the de novo genome assemblies, detailed annotation, and comparative analysis of two closely related parasitoid wasps that target pest aphids: Aphidius ervi and Lysiphlebus fabarum (Hymenoptera: Braconidae: Aphidiinae). The genomes are small (139 and 141 Mbp) and the most AT-rich reported thus far for any arthropod (GC content: 25.8 and 23.8%). This nucleotide bias is accompanied by skewed codon usage and is stronger in genes with adult-biased expression. AT-richness may be the consequence of reduced genome size, a near absence of DNA methylation, and energy efficiency. We identify missing desaturase genes, whose absence may underlie mimicry in the cuticular hydrocarbon profile of L. fabarum. We highlight key gene groups including those underlying venom composition, chemosensory perception, and sex determination, as well as potential losses in immune pathway genes. CONCLUSIONS: These findings are of fundamental interest for insect evolution and biological control applications. They provide a strong foundation for further functional studies into coevolution between parasitoids and their hosts. Both genomes are available at https://bipaa.genouest.org.

Ecdysteroidogenesis in Heliothis virescens (Lepidoptera: Noctuidae): Recombinant Prothoracicotropic Hormone and Brain Extract Show Comparable Effects.

Prothoracicotropic hormone (PTTH) is a neuropeptide that triggers a cascade of events within the prothoracic gland (PG) cells, leading to the activation of all the crucial enzymes involved in ecdysone biosynthesis, the main insect steroid hormone. Studies concerning ecdysteroidogenesis predicted PTTH action using brain extract (BE), consisting in a complex mixture in which some components positively or negatively interfere with PTTH-stimulated ecdysteroidogenesis. Consequently, the integration of these opposing factors in steroidogenic tissues leads to a complex secretory pattern. A recombinant form of prothoracicotropic hormone (rPTTH) from the tobacco budworm Heliothis virescens (F.) (Lepidoptera: Noctuidae) was expressed and purified to perform in vitro tests in a standard and repeatable manner. A characterization of rPTTH primary and secondary structures was performed. The ability of rPTTH and H. virescens BE to stimulate ecdysteroidogenesis was investigated on the third day of fifth larval stage. rPTTH activity was compared with the BE mixture by enzyme immunoassay and western blot, revealing that they equally stimulate the production of significant amount of ecdysone, through a transduction cascade that includes the TOR pathway, by the phosphorylation of 4E binding protein (4E-BP) and S6 kinase (S6K), the main targets of TOR protein. The results of these experiments suggest the importance of obtaining a functional pure hormone to perform further studies, not depending on the crude brain extract, composed by different elements and susceptible to different uncontrollable variables.

Thyroid hormone inhibition in L6 myoblasts of IGF-I-mediated glucose uptake and proliferation: new roles for integrin αvß3.

Thyroid hormones L-thyroxine (T4) and 3,3',5-triiodo-L-thyronine (T3) have been shown to initiate short- and long-term effects via a plasma membrane receptor site located on integrin αvß3. Also insulin-like growth factor type I (IGF-I) activity is known to be subject to regulation by this integrin. To investigate the possible cross-talk between T4 and IGF-I in rat L6 myoblasts, we have examined integrin αvß3-mediated modulatory actions of T4 on glucose uptake, measured through carrier-mediated 2-deoxy-[3H]-D-glucose uptake, and on cell proliferation stimulated by IGF-I, assessed by cell counting, [3H]-thymidine incorporation, and fluorescence-activated cell sorting analysis. IGF-I stimulated glucose transport and cell proliferation via the cell surface IGF-I receptor (IGFIR) and, downstream of the receptor, by the phosphatidylinositol 3-kinase signal transduction pathway. Addition of 0.1 nM free T4 caused little or no cell proliferation but prevented both glucose uptake and proliferative actions of IGF-I. These actions of T4 were mediated by an Arg-Gly-Asp (RGD)-sensitive pathway, suggesting the existence of crosstalk between IGFIR and the T4 receptor located near the RGD recognition site on the integrin. An RGD-sequence-containing integrin inhibitor, a monoclonal antibody to αvß3, and the T4 metabolite tetraiodothyroacetic acid all blocked the inhibition by T4 of IGF-I-stimulated glucose uptake and cell proliferation. Western blotting confirmed roles for activated phosphatidylinositol 3-kinase and extracellular regulated kinase 1/2 (ERK1/2) in the effects of IGF-I and also showed a role for ERK1/2 in the actions of T4 that modified the effects of IGF-I. We conclude that thyroid hormone inhibits IGF-I-stimulated glucose uptake and cell proliferation in L6 myoblasts.

Potato leaf extract and its component, α-solanine, exert similar impacts on development and oxidative stress in Galleria mellonella L.

Plants synthesize a broad range of secondary metabolites that act as natural defenses against plant pathogens and herbivores. Among these, potato plants produce glycoalkaloids (GAs). In this study, we analyzed the effects of the dried extract of fresh potato leaves (EPL) on the biological parameters of the lepidopteran, Galleria mellonella (L.) and compared its activity to one of the main EPL components, the GA α-solanine. Wax moth larvae were reared from first instar on a diet supplemented with three concentrations of EPL or α-solanine. Both EPL and α-solanine affected survivorship, fecundity, and fertility of G. mellonella to approximately the same extent. We evaluated the effect of EPL and α-solanine on oxidative stress in midgut and fat body by measuring malondialdehyde (MDA) and protein carbonyl (PCO) contents, both biomarkers of oxidative damage. We evaluated glutathione S-transferase (GST) activity, a detoxifying enzyme acting in prevention of oxidative damage. EPL and α-solanine altered MDA and PCO concentrations and GST activity in fat body and midgut. We infer that the influence of EPL on G. mellonella is not enhanced by synergistic effects of the totality of potato leaf components compared to α-solanine alone.

Designing a public web-based information system to illustrate and disseminate the development and results of the DESIRE Project to combat desertification.

Until around 1995 it was challenging to make the scientific results of research projects publicly available except through presentations at meetings or conferences, or as papers in academic journals. Then it began to be clear that the Internet could become the main medium to publish and share new information with a much wider audience. The DESIRE Project (desertification mitigation and remediation of land-a global approach for local solutions) has built on expertise gained in previous projects to develop an innovative online 'Harmonized Information System' (HIS). This documents the context, delivery and evaluation of all tasks in the DESIRE Project using non-scientific terminology, with much of it also available in the local languages of the study sites. The DESIRE-HIS makes use of new possibilities for communication, including video clips, interactive tools, and links to social media networks such as Twitter. Dissemination of research results using this approach has required careful planning and design. This paper sets out the steps that have culminated in a complete online Information System about local solutions to global land management problems in desertification-affected areas, including many practical guidelines for responsible land management. As many of those who are affected by desertification do not have Internet access, printable dissemination materials are also available on the DESIRE-HIS.

In vitro antifungal activity and in vivo edible coating efficacy of insect-derived chitosan against Botrytis cinerea in strawberry.

Strawberry is a perishable fruit, susceptible to development of rot by a range of fungi, in particular Botrytis cinerea. Chitosan represents an alternative to agrochemicals for improving shelf-life and fighting fungal pathogens. A chitosan-based coating derived from pupal exuviae of Hermetia illucens has been recently formulated for improving shelf-life of strawberry stored at 4 °C and mixed condition (4 °C and room temperature). The effects of a decolored (PEDEC) and not decolored (PEND) chitosan from the black soldier fly were evaluated and compared with commercial chitosans from crustaceans (CCs), in vitro and in vivo. An inhibition/reduction of fungal growth and a disturbance of normal fungal morphology were observed, being MIC of 0.5 mg mL-1 and 1 mg mL-1 and growth inhibition of 70 % and 4% for PEND and PEDEC, respectively. Both edible coatings distributed via aerograph showed equal or better potential application than CCs in controlling B. cinerea in strawberry post-harvest treated. Different effects for chitosans depended on their different molecular weight and deacetylation degree distributions, and the presence or absence of melanin pigments in their structure. PEND could act directly against the fungus, with effects predominantly associated with fungitoxic properties; PEDEC might principally provide viable alternatives, such as the elicitation of biochemical defense responses in fruits, for example through total phenols, in particular the flavonoids.

Larval Frass of Hermetia illucens as Organic Fertilizer: Composition and Beneficial Effects on Different Crops.

Hermetia illucens has received a lot of attention as its larval stage can grow on organic substrates, even those that are decomposing. Black soldier fly breeding provides a variety of valuable products, including frass, a mixture of larval excrements, larval exuviae, and leftover feedstock, that can be used as a fertilizer in agriculture. Organic fertilizers, such as frass, bringing beneficial bacteria and organic materials into the soil, improves its health and fertility. This comprehensive review delves into a comparative analysis of frass derived from larvae fed on different substrates. The composition of micro- and macro-nutrients, pH levels, organic matter content, electrical conductivity, moisture levels, and the proportion of dry matter are under consideration. The effect of different feeding substrates on the presence of potentially beneficial bacteria for plant growth within the frass is also reported. A critical feature examined in this review is the post-application beneficial impacts of frass on crops, highlighting the agricultural benefits and drawbacks of introducing Hermetia illucens frass into cultivation operations. One notable feature of this review is the categorization of the crops studied into distinct groups, which is useful to simplify comparisons in future research.

Identification of Multifunctional Putative Bioactive Peptides in the Insect Model Red Palm Weevil (Rhynchophorus ferrugineus).

Innate immunity, the body's initial defense against bacteria, fungi, and viruses, heavily depends on antimicrobial peptides (AMPs), which are small molecules produced by all living organisms. Insects, with their vast biodiversity, are one of the most abundant and innovative sources of AMPs. In this study, AMPs from the red palm weevil (RPW) Rhynchophorus ferrugineus (Coleoptera: Curculionidae), a known invasive pest of palm species, were examined. The AMPs were identified in the transcriptomes from different body parts of male and female adults, under different experimental conditions, including specimens collected from the field and those reared in the laboratory. The RPW transcriptomes were examined to predict antimicrobial activity, and all sequences putatively encoding AMPs were analyzed using several machine learning algorithms available in the CAMPR3 database. Additionally, anticancer, antiviral, and antifungal activity of the peptides were predicted using iACP, AVPpred, and Antifp server tools, respectively. Physicochemical parameters were assessed using the Antimicrobial Peptide Database Calculator and Predictor. From these analyses, 198 putatively active peptides were identified, which can be tested in future studies to validate the in silico predictions. Genome-wide analysis revealed that several AMPs have predominantly emerged through gene duplication. Noticeably, we detect a newly originated defensin allele from an ancestral defensin via the deletion of two amino acids following gene duplication in RPW, which may confer an enhanced resilience to microbial infection. Our study shed light on AMP gene families and shows that high duplication and deletion rates are essential to achieve a diversity of antimicrobial mechanisms; hence, we propose the RPW AMPs as a model for exploring gene duplication and functional variations against microbial infection.

A comprehensive characterization of Hermetia illucens derived chitosan produced through homogeneous deacetylation.

The increasing demand for chitin and chitosan is driving research to explore alternative sources to crustaceans. Insects, particularly bioconverters as Hermetia illucens, are promising substitutes as they process food industry waste into valuable molecules, including chitin. Chitosan can be produced by chitin deacetylation: hot deacetylation to obtain a heterogeneous chitosan, the commonly produced, and cold deacetylation to obtain a homogeneous chitosan, not widely available. The two different treatments lead to a different arrangement of the amine and acetyl groups in the chitosan structure, affecting its molecular weight, deacetylation degree, and biological activity. This is the first report on the production and chemical-physical and biological characterization of homogenous chitosan derived from H. illucens larvae, pupal exuviae, and adults. This work, in addition to the report on heterogeneous chitosan by our research group, completes the overview of H. illucens chitosan. The yield values obtained for homogeneous chitosan from pupal exuviae (3 and 7 %) are in the range of insect (2-8 %) and crustaceans (4-15 %) chitosan. The evaluation of the antioxidant activity and antimicrobial properties against Gram-negative (Escherichia coli) and Gram-positive (Micrococcus flavus) bacteria confirmed the great versatility of H. illucens chitosan for biomedical and industrial applications and its suitability as an alternative source to crustaceans.

Insect-derived chitosan, a biopolymer for the increased shelf life of white and red grapes.

Post-harvest water loss and microbial infections are the root cause of the rapid deterioration of fresh fruit after the picking process, with both environmental and economic implications. Therefore, it is crucial to find solutions that can increase the shelf life of fresh fruits. For this purpose, edible coatings, naturally derived and non-synthetic, are acknowledged as a safe strategy. Among polymeric coatings, chitosan is one of the most effective. In this work, this biopolymer, produced from chitin extracted from Hermetia illucens, an alternative and more sustainable source than crustaceans (the commercial one), was exploited to extend the shelf life of white and red grapes. Chitosan from H. illucens pupal exuviae, at 0.5 % and 1 % concentrations, was applied on both grapes, which were then stored at room temperature or 4 °C. The study of chemical-physical parameters such as weight loss, Total Soluble Solids and pH, demonstrated the effectiveness of the biopolymer, even better than crustacean chitosan. Moreover, the analysis of nutraceutical properties has demonstrated that this natural edible coating improves the quality of grapes, with beneficial effects for human health. The obtained results, therefore, confirmed the viability of using insect-chitosan as an alternative to crustaceans for the preservation of fresh food.

Morphological characterization of the antenna of Torymus sinensis (Hymenoptera: Torymidae) and a comparison within the superfamily Chalcidoidea.

The parasitoid Torymus sinensis (Hymenoptera: Torymidae) has been successfully used in Italy since 2005 for biological control of the invasive cynipid Dryocosmus kuriphilus (Hymenoptera: Cynipidae), highly destructive for the economically relevant Castanea sativa (Fagales: Fagaceae). In order to investigate the morphological aspects related to sensorial behavior, a fine morphology study of the antennae and their sensilla was conducted by scanning electron microscopy on both sexes of T. sinensis. The antennae, composed of a scape, a pedicel and a flagellum with ten flagellomeres, had chaetic sensilla of six subtypes, placoid sensilla of three subtypes, trichoid sensilla, sensilla with a roundish grooved tip, and coeloconic sensilla. The chaetic sensilla of the first three subtypes were found in the scape and in the pedicel, and those of the last three subtypes, together with trichoid, roundish grooved tip and coeloconic sensilla, were found only on flagellomeres. Sexual dimorphism was detected in the morphology of the proper pedicel and the flagellum, and in the presence and distribution of the sensilla and their subtypes. The morphological aspects of the antenna of T. sinensis and of its sensilla were compared with those found in the family Torymidae and in other families of the extremely diverse superfamily Chalcidoidea.

In Vitro Evaluation of the Antibacterial Activity of the Peptide Fractions Extracted from the Hemolymph of Hermetia illucens (Diptera: Stratiomyidae).

Antimicrobial peptides (AMPs) are a chemically and structurally heterogeneous family of molecules produced by a large variety of living organisms, whose expression is predominant in the sites most exposed to microbial invasion. One of the richest natural sources of AMPs is insects which, over the course of their very long evolutionary history, have adapted to numerous and different habitats by developing a powerful innate immune system that has allowed them to survive but also to assert themselves in the new environment. Recently, due to the increase in antibiotic-resistant bacterial strains, interest in AMPs has risen. In this work, we detected AMPs in the hemolymph of Hermetia illucens (Diptera, Stratiomyidae) larvae, following infection with Escherichia coli (Gram negative) or Micrococcus flavus (Gram positive) and from uninfected larvae. Peptide component, isolated via organic solvent precipitation, was analyzed by microbiological techniques. Subsequent mass spectrometry analysis allowed us to specifically identify peptides expressed in basal condition and peptides differentially expressed after bacterial challenge. We identified 33 AMPs in all the analyzed samples, of which 13 are specifically stimulated by Gram negative and/or Gram positive bacterial challenge. AMPs mostly expressed after bacterial challenge could be responsible for a more specific activity.

An Overview of Ovarian Calyx Fluid Proteins of Toxoneuron nigriceps (Viereck) (Hymenoptera: Braconidae): An Integrated Transcriptomic and Proteomic Approach.

The larval stages of the tobacco budworm, Heliothis virescens (Fabricius) (Lepidoptera: Noctuidae), are parasitized by the endophagous parasitoid wasp, Toxoneuron nigriceps (Viereck) (Hymenoptera: Braconidae). During the injections of eggs, this parasitoid wasp also injects into the host body the secretion of the venom gland and the calyx fluid, which contains a polydnavirus (T. nigriceps BracoVirus: TnBV) and the Ovarian calyx fluid Proteins (OPs). The effects of the OPs on the host immune system have recently been described. In particular, it has been demonstrated that the OPs cause hemocytes to undergo a number of changes, such as cellular oxidative stress, actin cytoskeleton modifications, vacuolization, and the inhibition of hemocyte encapsulation capacity, which results in both a loss of hemocyte functionality and cell death. In this study, by using a combined transcriptomic and proteomic analysis, the main components of T. nigriceps ovarian calyx fluid proteins were identified and their possible role in the parasitic syndrome was discussed. This study provides useful information to support the analysis of the function of ovarian calyx fluid proteins, to better understand T. nigriceps parasitization success and for a more thorough understanding of the components of ovarian calyx fluid proteins and their potential function in combination with other parasitoid factors.

Hermetia illucens, an innovative and sustainable source of chitosan-based coating for postharvest preservation of strawberries.

The ability of chitosan produced from pupal exuviae of Hermetia illucens to retard the decay of the local strawberry (Fragaria x ananassa) cultivar Melissa was investigated for the first time in this paper. The results demonstrated the effectiveness of insect chitosan compared to the commercial polymer in preserving and enhancing, at the same time, some physicochemical parameters (weight loss, pH and soluble solids content) and nutraceutical properties (total polyphenol content, total flavonoid content and total antioxidant activity) of strawberries stored at RT, 4°C and at mixed storage conditions (4°C + RT). Moreover, chitosan from H. illucens was also effective in reducing fungal decay and improving fruit shelf life. The obtained results confirm that insect chitosan, particularly deriving from H. illucens pupal exuviae, can be a viable alternative to crustacean one in safeguarding postharvest fruits.