Animal-Origin Prebiotics Based on Chitin: An Alternative for the Future? A Critical Review

Modulatory effects of red seaweeds (Palmaria palmata, Porphyra umbilicalis and Chondrus crispus) on the human gut microbiota via an in vitro model

This work investigated the nutritional and mineral composition of three red seaweed species, Palmaria palmata, Porphyra umbilicalis and Chondrus crispus, and an in vitro assay was performed to determinate the effects of the intake of whole red seaweed on gut microbiota, short chain fatty acids production and metabolic pathways. The results obtained showed that 100 g of seaweeds contained essential minerals such as 28-107 % daily needs of Ca, 183-600 % daily needs of Fe and 18-54 % daily needs of Zn, whereas low content were found for Cu and I. Seaweed digestion fermentation showed beneficial effects of gut microbiota, as increases in beneficial species such as Akkermansia muciniphila, and in some seaweed, Bifidobacterium adoslescentis, Bacteroides ovatus or Lactobacillus ruminis. Metabolic pathways did only found little significant differences with respect to inulin fermentation. In view of the results, red seaweed showed prebiotic effects on human gut microbiota.

Gut Microbiota Modulation Through Dietary Approaches Targeting Better Health During Metabolic Disorders

The impact of gut microbiota is known to play a significant role in an individual's metabolism and health. Many harmful food products or dietary imbalance adversely affect human health and changing lifestyle, environmental factors, and food habits may have their effect on gut microbiota. It has emerged that gut microbiota is regarded as an emerging metabolic organ, which is dependent on individual's diet and its composition. This review discusses the significance of lactic acid bacteria as a prominent inhabitant in the gut microbiota and the role of probiotics, prebiotics, and polyphenols to improve human health and metabolism. The role of fermented foods as an important source of probiotics and bioactive molecules is also discussed along with the role of gut microbiota in metabolic disorders like dyslipidemia, obesity, hypercholesterolemia, cancer, and hypertension. Finally, the review gives insights into the effective therapeutic prospects through gut microbiota alterations to tackle these metabolic disorders.

Comparative Analysis of the Gut Microbiota of Thai Indigenous Chicken Fed House Crickets

The gut microbiota is pivotal to chickens' overall health, influencing digestion, nutrient absorption, and immune function. Dietary compounds significantly impact gut microbiota composition. House crickets (Acheta domesticus) have emerged as an alternative protein source for animal feed, rich in proteins and beneficial fatty acids. This study compared the gut microbiota in the cecum and ileum of Thai indigenous chicken breeds (Betong Chicken, white feather with black bone chicken, and black feather with black bone chicken) fed with or without house crickets. Using Oxford Nanopore Technology of 16S rDNA, this study found a similar relative abundance of gut bacteria across groups, with dominant bacteria including Firmicute, Bacteroidetes, Proteobacteria, and Actinobacteria. LEfSe analysis identified differential abundance of beneficial bacteria, such as Ruminococcaceae, Rikenella, and Deferribacteres, in the cecum of the black feather with black bone chicken after cricket feeding. Additionally, Lactobacillaceae exhibited differential abundance in the ileum of this breed post-cricket diet. Consequently, this study provides new data into the gut microbiota of Thai indigenous chickens. It suggests that house cricket diets did not significantly alter microbiota diversity but may enhance beneficial bacteria in certain breeds.

Methods of Protein Extraction from House Crickets (Acheta domesticus) for Food Purposes

Global population is projected to reach 9.1 billion by 2050, emphasizing the need for increased food production. Edible insects, such as house crickets (Acheta domesticus), emerged as promising due to higher nutritional value and efficient feed conversion rates compared to conventional protein sources. Incorporating insect powders into new food products can improve consumer acceptance but often leads to poor technological food processing functionality and/or undesirable organoleptic characteristics. Protein isolates have proven to be effective in enhancing this functionality and consumer acceptance, but existent protein extraction methods still lack improvements concerning the optimization of protein extraction rates. This study aimed to address this gap by developing and comparing the yield of three different protein extraction methods using sodium hydroxide, ascorbic acid or alcalase from house crickets (Acheta domesticus) for food applications. Protein extraction was performed on cricket powder with a mean protein content of 46.35 g/100 g, and the results were evaluated. The enzymatic method shows the highest protein extraction rate at 69.91% with a mean protein content of 60.19 g/100 g, while extraction with NaOH or ascorbic acid resulted in rates of 60.44 and 46.34%, respectively. Further studies on technological food processing functionality and sensorial evaluation of products developed with this protein extract are recommended.

Cross-Cultural Comparison (13 Countries) of Consumers' Willingness to Eat Specific Insect Powders in Five Food Types

By 2050, the world's population will rise to 9 billion, which implies that it is necessary to double protein production. We should consider more sustainable, alternative forms of protein. A solution to this is the use of insects, which offer high levels of protein and require less water than poultry, pork, and beef production. The objective of this study was to evaluate 13 countries' consumer perceptions regarding the willingness to eat specific types of insects as powdered ingredients in five food types. An online survey was conducted using Check All That Apply (CATA) to assess consumer perceptions across 13 countries. Approximately 630 consumers in each country were surveyed (total n > 8100). The CATA data were analyzed using Cochran's Q test, which showed highly significant differences among countries. The willingness to eat insects varied by country, food type, and insect species. The results of this study can be used to understand consumers' perceptions of insects and offer an indicator that can be used when developing insect-containing foods in the future.

Integrative Roles of Functional Foods, Microbiotics, Nutrigenetics, and Nutrigenomics in Managing Type 2 Diabetes and Obesity

Diabetes and obesity are globally prevalent metabolic disorders posing significant public health challenges. The effective management of these conditions requires integrated and personalized strategies. This study conducted a systematic literature review, identifying 335 relevant papers, with 129 core articles selected after screening for duplicates and irrelevant studies. The focus of the study is on the synergistic roles of functional foods, microbiotics, and nutrigenomics. Functional foods, including phytochemicals (e.g., polyphenols and dietary fibers), zoochemicals (e.g., essential fatty acids), and bioactive compounds from macrofungi, exhibit significant potential in enhancing insulin sensitivity, regulating lipid metabolism, reducing inflammatory responses, and improving antioxidant capacity. Additionally, the critical role of gut microbiota in metabolic health is highlighted, as its interaction with functional foods facilitates the modulation of metabolic pathways. Nutrigenomics, encompassing nutrigenetics and genomics, reveals how genetic variations (e.g., single-nucleotide polymorphisms (SNPs)) influence dietary responses and gene expression, forming a feedback loop between dietary habits, genetic variations, gut microbiota, and metabolic health. This review integrates functional foods, gut microbiota, and genetic insights to propose comprehensive and sustainable personalized nutrition interventions, offering novel perspectives for preventing and managing type 2 diabetes and obesity. Future clinical studies are warranted to validate the long-term efficacy and safety of these strategies.

Chitosan and its derivatives: A novel approach to gut microbiota modulation and immune system enhancement

Chitosan, a biopolymer derived from the deacetylation of chitin found in crustacean shells and certain fungi, has attracted considerable attention for its promising health benefits, particularly in gut microbiota maintenance and immune system modulation. This review critically examines chitosan's multifaceted role in supporting gut health and enhancing immunity, beginning with a comprehensive overview of its sources, chemical structure, and its dual function as a dietary supplement and biomaterial. Chitosan's prebiotic effects are highlighted, with a focus on its ability to selectively stimulate beneficial gut bacteria, such as Bifidobacteria and Lactobacillus, while enhancing gut barrier integrity and inhibiting the growth of pathogenic microorganisms. The review delves deeply into chitosan's immunomodulatory mechanisms, including its impact on antigen-presenting cells, cytokine profiles, and systemic immune responses. A detailed comparative analysis assesses chitosan's efficacy relative to other prebiotics and immunomodulatory agents, examining challenges related to bioavailability and metabolic activity. Beyond its role in gut health, this review explores chitosan's potential as a dual-action agent that not only supports gut microbiota but also fortifies immune resilience. It introduces emerging research on novel chitosan derivatives, such as chitooligosaccharides, and evaluates their enhanced bioactivity for functional food applications. Special attention is given to sustainability, with an exploration of alternative, plant-based sources of chitosan and their implications for both health and environmental stewardship. Also, the review identifies new research avenues, such as the growing interest in chitosan's role in the gut-brain axis and its potential mental health benefits through microbial interactions. By addressing these innovative areas, the review aims to shift the focus from basic health effects to chitosan's broader impact on public health. The findings encourage further exploration, particularly through human trials, and emphasize chitosan's untapped potential in revolutionizing health and disease management.

Advances in bio-polymer coatings for probiotic microencapsulation: chitosan and beyond for enhanced stability and controlled release

This review paper analyzes recent advancements in bio-polymer coatings for probiotic microencapsulation, with a particular emphasis on chitosan and its synergistic combinations with other materials. Probiotic microencapsulation is essential for protecting probiotics from environmental stresses, enhancing their stability, and ensuring effective delivery to the gut. The review begins with an overview of probiotic microencapsulation, highlighting its significance in safeguarding probiotics through processing, storage, and gastrointestinal transit. Advances in chitosan-based encapsulation are explored, including the integration of chitosan with other bio-polymers such as alginate, gelatin, and pectin, as well as the application of nanotechnology and innovative encapsulation techniques like spray drying and layer-by-layer assembly. Detailed mechanistic insights are integrated, illustrating how chitosan influences gut microbiota by promoting beneficial bacteria and suppressing pathogens, thus enhancing its role as a prebiotic or synbiotic. Furthermore, the review delves into chitosan's immunomodulatory effects, particularly in the context of inflammatory bowel disease (IBD) and autoimmune diseases, describing the immune signaling pathways influenced by chitosan and linking gut microbiota changes to improvements in systemic immunity. Recent clinical trials and human studies assessing the efficacy of chitosan-coated probiotics are presented, alongside a discussion of practical applications and a comparison of in vitro and in vivo findings to highlight real-world relevance. The sustainability of chitosan sources and their environmental impact are addressed, along with the novel concept of chitosan's role in the gut-brain axis. Finally, the review emphasizes future research needs, including the development of personalized probiotic therapies and the exploration of novel bio-polymers and encapsulation techniques.

Microbiota modulation by the inclusion of Tenebrio molitor larvae as alternative to fermented soy protein concentrate in growing pigs diet

Tenebrio molitor meal represents a promising protein source for animal nutrition due to its low environmental impact and high nutritional value. To date, there is limited data in the literature regarding the effects of Tenebrio molitor meal on the modulation of gut microbiota in growing animals, with most results focusing on poultry rather than pigs. The aim of this study was to evaluate the effects of replacing fermented soy protein concentrate with Tenebrio molitor meal on gut microbiota and feed digestibility in growing pigs. A total of 14 growing pigs (80 ± 2 days old) were randomly allotted to two groups: the control group (CON) was fed a commercial diet containing 4% fermented soy protein concentrate (48% crude protein), and the treatment group (TM) was fed a basal diet containing 5% of T. molitor larvae meal formulated to be isonitrogenous and isoenergetic. The study lasted 28 days. Animals were weekly weighted and feed refuse was routinely measured. Fecal, blood samples, and rectal swabs were collected for analysis. No differences were observed in growth and diet digestibility for the protein and lipid components throughout the trial. No differences in the serum concentrations of albumin, globulin, urea, and interleukin-6 were registered in both groups, suggesting an unaltered health status. The TM group showed a significant difference in the beta diversity index considering the total duration of the trial (treatment effect evaluated with PERMANOVA, R2 0.0771, p value = 0.0099) showing an increased abundance of Elusimicrobium spp. and a decrease in Asteroplasma spp. in TM compared to the CON group (p < 0.05). Obtained findings indicate that 5% T. molitor meal can be included as a partial replacement for soy in growing pig formula without impairing pig growth and gut microbiota composition.

Unravelling the Role of Chitin and Chitosan in Prebiotic Activity and Correlation With Cancer: A Narrative Review

This review describes the state of the art regarding the prebiotic role of chitin and the interactions of chitin and chitosan with cancer cells. Chitin is the second most abundant polysaccharide in nature and a constitutive component of crustacean shells and the exoskeleton of insects. Chitosan is the deacetylated form of chitin, which is obtained by chemical processing or the enzymatic activity of deacetylases found in microorganisms and insects. Edible insects have recently been introduced in Western countries, thus raising concerns regarding food safety and due to their chitin content and the release of chitosan during the digestive process. The roles of insect chitin and chitosan in the gastrointestinal tract, microbiome modulation, and cancer have been widely investigated. Several in vitro and in vivo studies have shown the possible microbiota modulation of chitin and its relevant communication with the immune system, thus confirming its prebiotic activity. No evidence has been provided on the cancerogenic activity of chitin; however, studies have suggested that chitin has a cytotoxic effect on cancer cell lines. Chitosan has been confirmed to exhibit apoptotic and cytotoxic activities on cancer cells in several in vitro studies on cancer cell lines and in vivo models. In conclusion, the literature does not show a direct connection between the presence of chitin or chitosan and the onset of cancer. However, cytotoxic and apoptotic activities in relation to cancerous lines have been demonstrated.

Prebiotic saccharides polymerization improves the encapsulation efficiency, stability, bioaccessibility and gut microbiota modulation of urolithin A liposomes

This work was to investigate the effect of four prebiotic saccharides gum arabic (GA), fructooligosaccharide (FOS), konjac glucomannan (KGM), and inulin (INU) incorporation on the encapsulation efficiency (EE), physicochemical stability, and in vitro digestion of urolithin A-loaded liposomes (UroA-LPs). The regulation of liposomes on gut microbiota was also investigated by in vitro colonic fermentation. Results indicated that liposomes coated with GA showed the best EE, bioaccessibility, storage and thermal stability, the bioaccessibility was 1.67 times of that of UroA-LPs. The UroA-LPs coated with FOS showed the best freeze-thaw stability and transformation. Meanwhile, saccharides addition remarkably improved the relative abundance of Bacteroidota, reduced the abundances of Proteobacteria and Actinobacteria. The UroA-LPs coated with FOS, INU, and GA exhibited the highest beneficial bacteria abundance of Parabacteroides, Monoglobus, and Phascolarctobacterium, respectively. FOS could also decrease the abundance of harmful bacteria Collinsella and Enterococcus, and increase the levels of acetic acid, butyric acid and iso-butyric acid. Consequently, prebiotic saccharides can improve the EE, physicochemical stability, gut microbiota regulation of UroA-LPs, and promote the bioaccessibility of UroA, but the efficiency varied based on saccharides types, which can lay a foundation for the application of UroA in foods industry and for the enhancement of its bio-activities.

Eco-friendly and safe alternatives for the valorization of shrimp farming waste

The seafood industry generates waste, including shells, bones, intestines, and wastewater. The discards are nutrient-rich, containing varying concentrations of carotenoids, proteins, chitin, and other minerals. Thus, it is imperative to subject seafood waste, including shrimp waste (SW), to secondary processing and valorization for demineralization and deproteination to retrieve industrially essential compounds. Although several chemical processes are available for SW processing, most of them are inherently ecotoxic. Bioconversion of SW is cost-effective, ecofriendly, and safe. Microbial fermentation and the action of exogenous enzymes are among the significant SW bioconversion processes that transform seafood waste into valuable products. SW is a potential raw material for agrochemicals, microbial culture media, adsorbents, therapeutics, nutraceuticals, and bio-nanomaterials. This review comprehensively elucidates the valorization approaches of SW, addressing the drawbacks of chemically mediated methods for SW treatments. It is a broad overview of the applications associated with nutrient-rich SW, besides highlighting the role of major shrimp-producing countries in exploring SW to achieve safe, ecofriendly, and efficient bio-products.

In vitro antibiofilm, antibacterial, antioxidant, and antitumor activities of the brown alga Padina pavonica biomass extract

The antibiofilm, antibacterial, antioxidant, and anticancer activities of the methanolic extract of Padina pavonica L. were determined. Results deduced that the algal extract had a high biofilm formation inhibitory action done via crystal violet (CV) assay, to 88-99%. The results showed a strong antibacterial against the identified bacteria species. Staphylococcus aureus, Enterococcus faecalis, Pseudomonas aeruginosa, Klebsiella pneumonia, Bacillus subtilis, and the extract had moderate antibacterial activity against Escherichia coli, Pseudomonas fluorescens and Streptococcus agalactiae. The algal extract has a concentration-dependent DPPH radical scavenging activity (84.59%, with IC50 = 170.31 µg/ml). The inhibitory percent of P. pavonica methanolic extract in vitro antiproliferative activity was 1.79-98.25% with IC50 = 15.14 µg/ml against lung carcinoma. Phenols, terpenes, amino acids, alkaloids, flavones, alcohols, and fatty acids were among the metabolites whose biological actions were evaluated. In conclusion, for the first time, P. pavonica methanolic extract exhibited effective antibiofilm, antibacterial, antioxidant, and anticancer activities.      .

Integrating microbiome science and evolutionary medicine into animal health and conservation

Microbiome science has provided groundbreaking insights into human and animal health. Similarly, evolutionary medicine - the incorporation of eco-evolutionary concepts into primarily human medical theory and practice - is increasingly recognised for its novel perspectives on modern diseases. Studies of host-microbe relationships have been expanded beyond humans to include a wide range of animal taxa, adding new facets to our understanding of animal ecology, evolution, behaviour, and health. In this review, we propose that a broader application of evolutionary medicine, combined with microbiome science, can provide valuable and innovative perspectives on animal care and conservation. First, we draw on classic ecological principles, such as alternative stable states, to propose an eco-evolutionary framework for understanding variation in animal microbiomes and their role in animal health and wellbeing. With a focus on mammalian gut microbiomes, we apply this framework to populations of animals under human care, with particular relevance to the many animal species that suffer diseases linked to gut microbial dysfunction (e.g. gut distress and infection, autoimmune disorders, obesity). We discuss diet and microbial landscapes (i.e. the microbes in the animal's external environment), as two factors that are (i) proposed to represent evolutionary mismatches for captive animals, (ii) linked to gut microbiome structure and function, and (iii) potentially best understood from an evolutionary medicine perspective. Keeping within our evolutionary framework, we highlight the potential benefits - and pitfalls - of modern microbial therapies, such as pre- and probiotics, faecal microbiota transplants, and microbial rewilding. We discuss the limited, yet growing, empirical evidence for the use of microbial therapies to modulate animal gut microbiomes beneficially. Interspersed throughout, we propose 12 actionable steps, grounded in evolutionary medicine, that can be applied to practical animal care and management. We encourage that these actionable steps be paired with integration of eco-evolutionary perspectives into our definitions of appropriate animal care standards. The evolutionary perspectives proposed herein may be best appreciated when applied to the broad diversity of species under human care, rather than when solely focused on humans. We urge animal care professionals, veterinarians, nutritionists, scientists, and others to collaborate on these efforts, allowing for simultaneous care of animal patients and the generation of valuable empirical data.

Edible insects as a source of biopeptides and their role in immunonutrition

Many edible insect species are attracting the attention of the food industry and consumers in Western societies due to their high content and quality of protein, and consequently, the potential to be used as a more environmentally friendly dietary source could be beneficial for humans. On the other hand, prevention of inflammatory diseases using nutritional interventions is currently being proposed as a sustainable and cost-effective strategy to improve people's health. In this regard, finding bioactive compounds such as peptides with anti-inflammatory properties from sustainable sources (e.g., edible insects) is one area of particular interest, which might have a relevant role in immunonutrition. This review aims to summarize the recent literature on the discovery of immunomodulatory peptides through in vitro studies from edible insects, as well as to describe cell-based assays aiming to prove their bioactivity. On top of that, in vivo studies (i.e., animal and human), although scarce, have been mentioned in relation to the topic. In addition, the challenges and future perspectives related to edible-insect peptides and their role in immunonutrition are discussed. The amount of literature aiming to demonstrate the potential immunomodulatory activity of edible-insect peptides is scarce but promising. Different approaches have been employed, especially cell assays and animal studies employing insect meal as supplementation in the diet. Insects such as Tenebrio molitor or Gryllodes sigillatus are some of the most studied and have demonstrated to contain bioactive peptides. Further investigations, mostly with humans, are needed in order to clearly state that peptides from edible insects may contribute to the modulation of the immune system.

A scientific version of understanding "Why did the chickens cross the road"? - A guided journey through Bacillus spp. towards sustainable agriculture, circular economy and biofortification

The world, a famished planet with an overgrowing population, requires enormous food crops. This scenario compelled the farmers to use a high quantity of synthetic fertilizers for high food crop productivity. However, prolonged usage of chemical fertilizers results in severe adverse effects on soil and water quality. On the other hand, the growing population significantly consumes large quantities of poultry meats. Eventually, this produces a mammoth amount of poultry waste, chicken feathers. Owing to the protein value of the chicken feathers, these wastes are converted into protein hydrolysate and further extend their application as biostimulants for sustained agriculture. The protein profile of chicken feather protein hydrolysate (CFPH) produced through Bacillus spp. was the maximum compared to physical and chemical protein extraction methods. Several studies proved that the application of CFPH and active Bacillus spp. culture to soil and plants results in enhanced plant growth, phytochemical constituents, crop yield, soil nutrients, fertility, microbiome and resistance against diverse abiotic and biotic stresses. Overall, "CFPH - Jack of all trades" and "Bacillus spp. - an active camouflage to the surroundings where they applied showed profound and significant benefits to the plant growth under the most adverse conditions. In addition, Bacillus spp. coheres the biofortification process in plants through the breakdown of metals into metal ions that eventually increase the nutrient value of the food crops. However, detailed information on them is missing. This can be overcome by further real-world studies on rhizoengineering through a multi-omics approach and their interaction with plants. This review has explored the best possible and efficient strategy for managing chicken feather wastes into protein-rich CFPH through Bacillus spp. bioconversion and utilizing the CFPH and Bacillus spp. as biostimulants, biofertilizers, biopesticides and biofortificants. This paper is an excellent report on organic waste management, circular economy and sustainable agriculture research frontier.

Mycelium: A Nutrient-Dense Food To Help Address World Hunger, Promote Health, and Support a Regenerative Food System

There is a need for transformational innovation within the existing food system to achieve United Nations Sustainable Development Goal 2 of ending hunger within a sustainable agricultural system by 2030. Mycelium, the vegetative growth form of filamentous fungi, may represent a convergence of several features crucial for the development of food products that are nutritious, desirable, scalable, affordable, and environmentally sustainable. Mycelium has gained interest as technology advances demonstrate its ability to provide scalable biomass for food production delivering good flavor and quality protein, fiber, and essential micronutrients urgently needed to improve public health. We review the potential of mycelium as an environmentally sustainable food to address malnutrition and undernutrition, driven by food insecurity and caloric dense diets with less than optimal macro- and micronutrient density.

Emerging relevance of cell wall components from non-conventional yeasts as functional ingredients for the food and feed industry

Non-conventional yeast species, or non-Saccharomyces yeasts, are increasingly recognized for their involvement in fermented foods. Many of them exhibit probiotic characteristics that are mainly due to direct contacts with other cell types through various molecular components of their cell wall. The biochemical composition and/or the molecular structure of the cell wall components are currently considered the primary determinant of their probiotic properties. Here we first present the techniques that are used to extract and analyze the cell wall components of food industry-related non-Saccharomyces yeasts. We then review the current understanding of the cell wall composition and structure of each polysaccharide from these yeasts. Finally, the data exploring the potential beneficial role of their cell wall components, which could be a source of innovative functional ingredients, are discussed. Such research would allow the development of high value-added products and provide the food industry with novel inputs beyond the well-established S. cerevisiae.

Protective Effects of Alginate and Chitosan Oligosaccharides against Clostridioides difficile Bacteria and Toxin

Clostridioides difficile infection is expected to become the most common healthcare-associated infection worldwide. C. difficile-induced pathogenicity is significantly attributed to its enterotoxin, TcdA, which primarily targets Rho-GTPases involved in regulating cytoskeletal and tight junction (TJ) dynamics, thus leading to cytoskeleton breakdown and ultimately increased intestinal permeability. This study investigated whether two non-digestible oligosaccharides (NDOs), alginate (AOS) and chitosan (COS) oligosaccharides, possess antipathogenic and barrier-protective properties against C. difficile bacteria and TcdA toxin, respectively. Both NDOs significantly reduced C. difficile growth, while cell cytotoxicity assays demonstrated that neither COS nor AOS significantly attenuated the TcdA-induced cell death 24 h post-exposure. The challenge of Caco-2 monolayers with increasing TcdA concentrations increased paracellular permeability, as measured by TEER and LY flux assays. In this experimental setup, COS completely abolished, and AOS mitigated, the deleterious effects of TcdA on the monolayer's integrity. These events were not accompanied by alterations in ZO-1 and occludin protein levels; however, immunofluorescence microscopy revealed that both AOS and COS prevented the TcdA-induced occludin mislocalization. Finally, both NDOs accelerated TJ reassembly upon a calcium-switch assay. Overall, this study established the antipathogenic and barrier-protective capacity of AOS and COS against C. difficile and its toxin, TcdA, while revealing their ability to promote TJ reassembly in Caco-2 cells.

Inclusion of up to 20% Black Soldier Fly larvae meal in broiler chicken diet has a minor effect on caecal microbiota

Background

The Black Soldier Fly larvae (BSFL) are a source of nutrients and bioactive compounds in broiler diets. Some components of the BSFL may serve as a prebiotic or may impact the intestinal microbiota of the broilers by other modes of action, which in turn can affect the health and performance of broilers. Here, we investigate the impact of up to 20% BSFL in broiler diets on the diversity and composition of the broiler's microbiota.

Methods

Four hundred broilers were fed five iso-nutritious experimental diets with increasing levels of BSFL meal reaching 0%, 5%, 10%, 15%, 20% in the finisher diets. Eight caecal content samples coming from each of the eight replicates per treatment were collected at two time points (day 21 and day 42) for DNA extraction and sequencing of the V3-V4 regions using Illumina MiSeq 2 × 300 bp pair-end sequencing with 341f and 805r primers. Analysis of variance and Spearman's correlation were performed, while QIIME2, DADA2, and Calypso were used for data analysis.

Results

When broilers were 21 days of age, the abundance of two groups of sequence variants representing Enterococcus and unclassified Christensenellaceae was significantly lower (p-value = 0.048 and p-value = 0.025, respectively) in the 20% BSFL group compared to the 0% BSFL group. There was no relevant alteration in the microbiota diversity at that stage. On day 42, the Spearman correlation analysis demonstrated that the sequence variants representing the genus Coprococcus showed a negative relationship with the BSFL inclusion levels (p-value = 0.043). The sequence variants representing the genus Roseburia and Dehalobacterium demonstrated a positive relationship with the BSFL dietary inclusion (p-value = 0.0069 and p-value = 0.0034, respectively). There was a reduction in the dissimilarity index (ANOSIM) caused by the 20% BSFL dietary inclusion.

Conclusion

The addition of up to 20% BSFL in broiler diets did not affect the overall caeca microbiota diversity or composition at day 21. On day 42, there was a reduction in the beta diversity caused by the 20% BSFL dietary inclusion. The abundance of the bacterial group Roseburia was increased by the BSFL dietary inclusion, and it may be beneficial to broiler immunity and performance.

Yellow Mealworm (Tenebrio molitor) and Lesser Mealworm (Alphitobius diaperinus) Proteins Slowed Weight Gain and Improved Metabolism of Diet-Induced Obesity Mice

BACKGROUND

High-protein diets not only meet amino acid needs but also modulate satiety and energy metabolism. Insect-based proteins are sustainable, high-quality proteins. Mealworms have been studied, but limited information is known about their ability to impact metabolism and obesity.

OBJECTIVE

We determined the effects of defatted yellow mealworm (Tenebrio molitor)- and whole lesser mealworm (Alphitobius diaperinus)-based proteins on the body weight (BW), serum metabolites, and liver and adipose tissue (AT) histology and gene expression of diet-induced obesity mice.

METHODS

Male C57BL/6J mice were fed a high-fat diet (HFD; 46% kcal) to induce obesity and metabolic syndrome. Obese mice were then assigned to treatments (n = 10/group) and fed for 8 wk: HFD: HFD with casein protein; B50: HFD with 50% protein from whole lesser mealworm; B100: HFD with 100% protein from whole lesser mealworm; Y50: HFD with 50% protein from defatted yellow mealworm; Y100: HFD with 100% protein from defatted yellow mealworm. Lean mice (n = 10) fed a low-fat-diet (LFD; 10% kcal) were included. Longitudinal food intake, BW, body composition, and glucose response were measured. At time of killing, serum metabolites, tissue histopathology and gene expression, and hepatic triglycerides were analyzed.

RESULTS

After 8 wk, HFD, B50, and B100 had greater (P < 0.05) weight gain than LFD, whereas Y50 and Y100 did not. Y50, B100, and Y100 had a lower (P < 0.05) BW change rate than HFD. Mealworm-based diets led to increased (P < 0.05) serum high-density lipoprotein (HDL) and reduced (P < 0.05) serum low-density lipoprotein (LDL) concentrations and reduced (P<0.05) LDL/HDL ratio. Mealworm-based diets led to increased (P < 0.05) hepatic expression of genes related to energy balance, immune response, and antioxidants and reduced (P < 0.05) AT expression of genes associated with inflammation and apoptosis. Mealworm-based diets altered (P < 0.05) hepatic and AT expression of glucose and lipid metabolism genes.

CONCLUSIONS

In addition to serving as an alternative protein source, mealworms may confer health benefits to obese patients.

Utilization of Tenebrio molitor Larvae Reared with Different Substrates as Feed Ingredients in Growing Pigs

The procurement of adequate feed resources is one of the most important challenges for the animal industry worldwide. While the need for feeds rich in protein is constantly increasing, their production cannot readily keep up. Consequently, to overcome this challenge in a sustainable way, it is necessary to identify and develop new feeding strategies and feed ingredients, such as insect meals. In the present study, Tenebrio molitor larvae that were reared on two different substrates (standard and enriched with medicinal aromatic plant material) were used as feed ingredients for growing pigs. A total of 36 weaned pigs (34 days old) were randomly allocated to three treatment groups and fed either the control diet (A) or diets supplemented at 10% with one of the two insect meals (B and C). At the end of the trial (42 days), blood, feces, and meat samples were collected for analysis. The insect meal supplementation did not affect (p > 0.05) overall performance but significantly modified (p < 0.001) the fecal microflora balance and the blood cholesterol (p < 0.001), while the rest of the blood parameters tested were not affected. Moreover, this dietary supplementation significantly affected some microbial populations (p < 0.001), improved the total phenolic content (p < 0.05), and the fatty acid profile (p < 0.001) of the meat cuts, but did not affect (p > 0.05) meat color or proximate composition. Further research is needed to evaluate the different types and levels of inclusion of insect meals in pig nutrition.

Chitin and omega-3 fatty acids in edible insects have underexplored benefits for the gut microbiome and human health

A healthy gut microbiome is critical for nutrient metabolism, pathogen inhibition and immune regulation, and is highly influenced by diet. Edible insects are good sources of protein and micronutrients, but unlike other animal-derived foods, they also contain both dietary fibre and omega-3 fatty acids that can modulate gut microbiota. Here we explore the potential impacts of insect consumption on the microbiome. Laboratory, animal and human studies indicate that insect fibre in the form of chitin and its derivatives can modify gut microbiota with beneficial outcomes. Some insects also contain favourable omega-3/omega-6 ratios. We identify gaps in the literature-especially a dearth of human studies-that must be addressed to better understand health impacts of entomophagy. Insects, already eaten across the globe, can be farmed using fewer resources than conventional livestock. Widening the research scope offers an opportunity to advance use of edible insects to address interconnected environmental and health challenges.

The Human Gut Virome and Its Relationship with Nontransmissible Chronic Diseases

The human gastrointestinal tract contains large communities of microorganisms that are in constant interaction with the host, playing an essential role in the regulation of several metabolic processes. Among the gut microbial communities, the gut bacteriome has been most widely studied in recent decades. However, in recent years, there has been increasing interest in studying the influences that other microbial groups can exert on the host. Among them, the gut virome is attracting great interest because viruses can interact with the host immune system and metabolic functions; this is also the case for phages, which interact with the bacterial microbiota. The antecedents of virome-rectification-based therapies among various diseases were also investigated. In the near future, stool metagenomic investigation should include the identification of bacteria and phages, as well as their correlation networks, to better understand gut microbiota activity in metabolic disease progression.

Population dynamics of Brachionus calyciflorus driven by the associated natural bacterioplankton

Zooplankton provides bacteria with a complex microhabitat richen in organic and inorganic nutrients, and the bacteria community also changes the physiochemical conditions for zooplankton, where the symbiotic relationship between them plays an important role in the nutrient cycle. However, there are few studies on the effect of associated bacteria on the population dynamics of rotifers. In order to make clear their relationships, we reconstructed the associated bacterial community in Brachionus calyciflorus culture, and examined the life history and population growth parameters, and analyzed the diversity and community composition of the associated bacteria at different growth stages of B. calyciflorus. The results showed that the addition of bacteria from natural water can promote the population growth and asexual reproduction of B. calyciflorus, but has no significant effect on sexual reproduction, exhibited by the improvement of its life expectancy at hatching, net reproduction rates and intrinsic growth rate, no significant effects on the generation time and mixis ratio of offspring. It was found that the B. calyciflorus-associated bacterial community was mainly composed of Proteobacteria, Bacteroidota, Actinobacteriota, Cyanobacteria and Firmicutes. Through correlation network analysis, the members of Burkholderiales, Pseudomonadales, Micrococcales, Caulobacterales and Bifidobacteriales were the keystone taxa of B. calyciflorus-associated bacteria. In addition, the relative abundance of some specific bacteria strains increased as the population density of B. calyciflorus increased, such as Hydrogenophaga, Acidovorax, Flavobacterium, Rheinheimera, Novosphingobium and Limnobacter, and their relative abundance increased obviously during the slow and exponential phases of population growth. Meanwhile, the relative abundance of adverse taxa (such as Elizabethkingia and Rickettsiales) decreased significantly with the increase in rotifer population density. In conclusion, the closely associated bacteria are not sufficient for the best growth of B. calyciflorus, and external bacterioplankton is necessary. Furthermore, the function of keystone and rare taxa is necessary for further exploration. The investigation of the symbiotic relationship between zooplankton-associated bacterial and bacterioplankton communities will contribute to monitoring their roles in freshwater ecosystems, and regulate the population dynamics of the micro-food web.

Dietary supplementation with full-fat Hermetia illucens larvae and multi-probiotics, as a substitute for antibiotics, improves the growth performance, gut health, and antioxidative capacity of weaned pigs

BACKGROUND

Dietary supplementation of full-fat black soldier fly larvae (BSFL full-fat meal; alone or in combination with multi-probiotics) was tested as an alternative to dietary antibiotics in weaning piglets. We also tested the effects of these diets on growth performance, nutrient digestibility coefficients, immune status, oxidative stress, intestinal histomorphology, and rectal microbial modulations in weaned pigs. A total of 80 piglets [(Landrace × Large White) × Duroc] of both sexes (a ratio of gilts and barrows; 1:1), were randomly allotted to four diet groups: positive control (PC) diet supplemented with 0.02% amoxicillin; negative control (NC) diet without supplement addition; BSFL12 diet (NC + 12% BSFL full-fat meal); and BSFL + Pro diet (BSFL full-fat meal + 0.1% multi-probiotics, including Bacillus subtilis, B. licheniformis, and Saccharomyces cerevisiae). All groups had five replicates, with four piglets per replicate.

RESULTS

Dietary BSFL + Pro improved the overall average daily gain (P = 0.013), and gain-to-feed ratio (P = 0.032). The BSFL12 and BSFL + Pro diets improved nutrient digestibility and increased the serum levels of immunoglobulin A and glutathione peroxidase, while reducing the levels of pro-inflammatory cytokines. The spleen weight was higher and caecal pH was lower in pigs fed the BSFL + Pro diet than in those fed the NC diet (P = 0.011 and P = 0.021, respectively). Pigs fed the BSFL diets had longer duodenal villi, a higher villus height-to-crypt depth ratio (P = 0.004), and shorter crypt depth (P = 0.017) than those fed NC. The BSFL + Pro diet also increased faecal Lactobacillus spp. count (P = 0.008) and reduced Escherichia coli (P = 0.021) counts compared with that seen with PC and NC diets, respectively.

CONCLUSIONS

Dietary supplementation with BSFL or BSFL + multi-probiotics can improve the growth performance and intestinal health of pigs and may be an effective strategy to replace antibiotics for weaned pigs.

Wool keratin as a novel alternative protein: A comprehensive review of extraction, purification, nutrition, safety, and food applications

The growing global population and lifestyle changes have increased the demand for specialized diets that require protein and other essential nutrients for humans. Recent technological advances have enabled the use of food bioresources treated as waste as additional sources of alternative proteins. Sheep wool is an inexpensive and readily available bioresource containing 95%-98% protein, making it an outstanding potential source of protein for food and biotechnological applications. The strong structure of wool and its indigestibility are the main hurdles to achieving its potential as an edible protein. Although various methods have been investigated for the hydrolysis of wool into keratin, only a few of these, such as sulfitolysis, oxidation, and enzymatic processes, have the potential to generate edible keratin. In vitro and in vivo cytotoxicity studies reported no cytotoxicity effects of extracted keratin, suggesting its potential for use as a high-value protein ingredient that supports normal body functions. Keratin has a high cysteine content that can support healthy epithelia, glutathione synthesis, antioxidant functions, and skeletal muscle functions. With the recent spike in new keratin extraction methods, extensive long-term investigations that examine prolonged exposure of keratin generated from these techniques in animal and human subjects are required to ascertain its safety. Food applications of wool could improve the ecological footprint of sheep farming and unlock the potential of a sustainable protein source that meets demands for ethical production of animal protein.

Direct Action of Non-Digestible Oligosaccharides against a Leaky Gut

The epithelial monolayer is the primary determinant of mucosal barrier function, and tight junction (TJ) complexes seal the paracellular space between the adjacent epithelial cells and represent the main "gate-keepers" of the paracellular route. Impaired TJ functionality results in increased permeation of the "pro-inflammatory" luminal contents to the circulation that induces local and systemic inflammatory and immune responses, ultimately triggering and/or perpetuating (chronic) systemic inflammatory disorders. Increased gut leakiness is associated with intestinal and systemic disease states such as inflammatory bowel disease and neurodegenerative diseases such as Parkinson's disease. Modulation of TJ dynamics is an appealing strategy aiming at inflammatory conditions associated with compromised intestinal epithelial function. Recently there has been a growing interest in nutraceuticals, particularly in non-digestible oligosaccharides (NDOs). NDOs confer innumerable health benefits via microbiome-shaping and gut microbiota-related immune responses, including enhancement of epithelial barrier integrity. Emerging evidence supports that NDOs also exert health-beneficial effects on microbiota independently via direct interactions with intestinal epithelial and immune cells. Among these valuable features, NDOs promote barrier function by directly regulating TJs via AMPK-, PKC-, MAPK-, and TLR-associated pathways. This review provides a comprehensive overview of the epithelial barrier-protective effects of different NDOs with a special focus on their microbiota-independent modulation of TJs.

Nutritional composition, heavy metal content and in vitro effect on the human gut microbiota of Talitrus saltator, an underutilized crustacean from the Atlantic coast

In this study, an undervalued marine crustacean (Talitrus saltator) was characterized in terms of nutritional and heavy metal composition and its potential to affect human gut microbiota. Nutritional analysis of this crustacean revealed that it complies with the criteria established in European legislation to include nutritional claims in their labeling, such as "source of fiber," "low in fat," "low in sugars" and "high in protein." The analysis of the heavy metal content did not reveal any risk derived from the presence of Cd, Hg, or Pb, whereas essential metals contained in 100 g exceeded the minimum daily requirements recommended in Europe for Zn (19.78 mg/kg), Cu (2.28 mg/kg), and Fe (32.96 mg/kg). Using an in vitro system, the effect of T. saltator on the human colonic microbiota shows some beneficial effects, such as fermentation-maintained populations of Bifidobacterium or Lactobacillus, did not increase Firmicutes phylum counts, decreased the Firmicutes/Bacteroidetes ratio, and stimulated 11 metabolic pathways with respect to baseline. These results are unusual in a high protein content-food. However, negative effects were also found in gut microbiota relative proportions, such as an increase in the Proteobacteria phylum and especially some opportunistic bacteria from this phylum, probably due to the antimicrobial effect of chitin on other groups more sensitive to its effect. This work shows for the first time the effect of T. saltator on human colonic microbiota using and in vitro system. The presence of chitin in its composition could provide some beneficial effects by modulating the microbiota, but as T. saltator is a high-protein food, more studies should be carried out showing these benefits.

Chemical features and biological functions of water-insoluble dietary fiber in plant-based foods

Insoluble dietary fiber (IDF) is a nutritional component constituting the building block of plant cell walls. Our understanding of the role of IDF in plant-based foods has advanced dramatically in recent years. In this Review, we summarize research progress on the subtypes, structure, analysis, and extraction methods of IDF. The impact of different food processing methods on the properties of IDF is discussed. The role of gut microbiota in the health benefits of IDF is introduced. This review provides a better understanding of the chemical features and biological functions of IDF, which may promote the future application of IDF in functional food products. Further investigation of the mechanisms underlying the health benefits of IDF enables the development of effective strategies for the prevention and treatment of human diseases.

Polysaccharide-Based Edible Gels as Functional Ingredients: Characterization, Applicability, and Human Health Benefits

Nowadays, edible materials such as polysaccharides have gained attention due to their valuable attributes, especially gelling property. Polysaccharide-based edible gels (PEGs) can be classified as (i) hydrogels, (ii) oleogels and bigels, (iii) and aerogels, cryogels and xerogels, respectively. PEGs have different characteristics and benefits depending on the functional groups of polysaccharide chains (e.g., carboxylic, sulphonic, amino, methoxyl) and on the preparation method. However, PEGs are found in the incipient phase of research and most studies are related to their preparation, characterization, sustainable raw materials, and applicability. Furthermore, all these aspects are treated separately for each class of PEG, without offering an overview of those already obtained PEGs. The novelty of this manuscript is to offer an overview of the classification, definition, formulation, and characterization of PEGs. Furthermore, the applicability of PEGs in the food sector (e.g., food packaging, improving food profile agent, delivery systems) and in the medical/pharmaceutical sector is also critically discussed. Ultimately, the correlation between PEG consumption and polysaccharides properties for human health (e.g., intestinal microecology, "bridge effect" in obesity, gut microbiota) are critically discussed for the first time. Bigels may be valuable for use as ink for 3D food printing in personalized diets for human health treatment. PEGs have a significant role in developing smart materials as both ingredients and coatings and methods, and techniques for exploring PEGs are essential. PEGs as carriers of bioactive compounds have a demonstrated effect on obesity. All the physical, chemical, and biological interactions among PEGs and other organic and inorganic structures should be investigated.

Chitosan and Chitooligosaccharide: The Promising Non-Plant-Derived Prebiotics with Multiple Biological Activities

Biodegradable chitin is the second-most abundant natural polysaccharide, widely existing in the exoskeletons of crabs, shrimps, insects, and the cell walls of fungi. Chitosan and chitooligosaccharide (COS, also named chitosan oligosaccharide) are the two most important deacetylated derivatives of chitin. Compared with chitin, chitosan and COS not only have more satisfactory physicochemical properties but also exhibit additional biological activities, which cause them to be widely applied in the fields of food, medicine, and agriculture. Additionally, due to their significant ability to improve gut microbiota, chitosan and COS are deemed prospective prebiotics. Here, we introduced the production, physicochemical properties, applications, and pharmacokinetic characteristics of chitosan and COS. Furthermore, we summarized the latest research on their antioxidant, anti-inflammatory, and antimicrobial activities. Research progress on the prebiotic functions of chitosan and COS is particularly reviewed. We creatively analyzed and discussed the mechanisms and correlations underlying these activities of chitosan and COS and their physicochemical properties. Our work enriched people's understanding of these non-plant-derived prebiotics. Based on this review, the future directions of research on chitosan and COS are explored. Collectively, optimizing the production technology of chitin derivatives and enriching understanding of their biological functions will shed more light on their capability to improve human health.

Full-fat field cricket (Gryllus bimaculatus) as a substitute for fish meal and soybean meal for weaning piglets: effects on growth performance, intestinal health, and redox status

Full-fat field cricket meal (FCP) is an alternative protein ingredient in livestock production; however, the effects of replacing conventional protein sources with FCP in nursery diets have not been determined. In this study, the effects of the partial replacement of either fish meal or soybean meal with FCP on weaning pigs were evaluated, including the analyses of growth performance, nutrient utilization, intestinal morphology, 
immunity, oxidative stress, and fecal microbial counts. A total of 100 crossbred weaning pigs [(Landrace × Large White) × Duroc] were allotted to one of the following five treatments with five replicates (four pigs/pen) and fed for 28 d postweaning. Treatments were 1) a corn-soybean meal (SBM)-based diet with 5% fish meal (Positive control; PC), 2) a corn-SBM-based diet without fish meal (Negative control; NC), 3) field crickets replacing fishmeal on a total Lys basis (FCP1), 4) field crickets replacing fishmeal on a kg/kg basis (FCP2), and 5) field crickets replacing fish meal and soybean meal (FCP3). The piglets on FCP1 had a higher body weight on days 14 and 28, and an increased average daily gain over the experimental period than NC (P < 0.05); FCP2 and FCP3 were similar to the FCP1 treatment. The incidence of diarrhea was lower under an FCP-supplemented diet than under the NC diet throughout the study (P < 0.05). Pigs fed FCP1 and FCP2 had a higher digestibility of crude 
protein (P = 0.041), and all FCP groups increased crude fat digestibility (P = 0.024). FCP1 and FCP2 also increased jejunal villus height 
(P = 0.009), whereas the increase in jejunal villus-to-crypt ratios (P = 0.019) was greater in pigs fed the FCP2 diet than those fed the NC diet. Furthermore, FCP2 supplementation increased serum immunoglobulin A levels on days 14 and 28, including reduced serum interleukin-6 and tumor necrosis factor alpha levels (P < 0.05). Pigs fed an FCP2 diet had reduced malondialdehyde levels than those fed a PC diet, while pigs fed an FCP2 diet had higher superoxide dismutase and glutathione peroxidase levels, and more fecal Lactobacillus spp. than those fed an NC diet (P < 0.05). These results support the use of FCP as an alternative protein ingredient with beneficial effects on growth performance, intestinal morphology, antioxidant capacity, and intestinal microbiota. In particular, FCP can be used as a partial substitute for fish meal and soybean meal without detrimental effects on weaning pigs.

Chitin derivatives ameliorate DSS-induced ulcerative colitis by changing gut microbiota and restoring intestinal barrier function

Chitin derivatives (CDs), including chitosan (CS), chitooligosaccharides (COS), and glucosamine (GlcN), were administrated in dextran sodium sulfate (DSS)-induced ulcerative colitis (UC) mice. UC symptoms such as body weight loss, reduced food intake, and increased disease activity index were relieved (except GlcNL group). CDs (except GlcNL) exerted a strong protective effect on colon length and colonic structure. Treatment with CDs (except GlcNL) increased IL-10 level, reduced levels of IL-1β, IL-6, TNF-α, myeloperoxidase, and inducible nitric oxide synthase, and enhanced expression of tight junction proteins significantly. CDs (except GlcNL) significantly upregulated IκB-α level, and downregulated p65 and p38 phosphory lation and TLR-4 mRNA transcription level, indicating inhibition of TRL-4/NF-κB/MAPK signaling pathway activity. CD treatments increased relative abundance of gut microbiota, modulated its composition, and increased the concentrations of SCFAs. Our findings indicate that CDs exert an ameliorative effect on UC by change of gut microbiota composition and restoration of intestinal barrier function.

Yellow Mealworm and Black Soldier Fly Larvae for Feed and Food Production in Europe, with Emphasis on Iceland

Insects are part of the diet of over 2 billion people worldwide; however, insects have not been popular in Europe, neither as food nor as a feed ingredient. This has been changing in recent years, due to increased knowledge regarding the nutritional benefits, the need for novel protein production and the low environmental impact of insects compared to conventional protein production. The purpose of this study is to give an overview of the most popular insects farmed in Europe, yellow mealworm, Tenebrio molitor, and black soldier fly (BSF), Hermetia illucens, together with the main obstacles and risks. A comprehensive literature study was carried out and 27 insect farming companies found listed in Europe were contacted directly. The results show that the insect farming industry is increasing in Europe, and the success of the frontrunners is based on large investments in technology, automation and economy of scale. The interest of venture capital firms is noticeable, covering 90% of the investment costs in some cases. It is concluded that insect farming in Europe is likely to expand rapidly in the coming years, offering new proteins and other valuable products, not only as a feed ingredient, but also for human consumption. European regulations have additionally been rapidly changing, with more freedom towards insects as food and feed. There is an increased knowledge regarding safety concerns of edible insects, and the results indicate that edible insects pose a smaller risk for zoonotic diseases than livestock. However, knowledge regarding risk posed by edible insects is still lacking, but food and feed safety is essential to put products on the European market.

Chitosan as a Valuable Biomolecule from Seafood Industry Waste in the Design of Green Food Packaging

Chitosan is a versatile biomolecule with a broad range of applications in food and pharmaceutical products. It can be obtained by the alkaline deacetylation of chitin. This biomolecule can be extracted using conventional or green methods from seafood industry residues, e.g., shrimp shells. Chitin has limited applications because of its low solubility in organic solvents. Chitosan is soluble in acidified solutions allowing its application in the food industry. Furthermore, biological properties, such as antioxidant, antimicrobial, as well as its biodegradability, biocompatibility and nontoxicity have contributed to its increasing application as active food packaging. Nevertheless, some physical and mechanical features have limited a broader range of applications of chitosan-based films. Green approaches may be used to address these limitations, leading to well-designed chitosan-based food packaging, by employing principles of a circular and sustainable economy. In this review, we summarize the properties of chitosan and present a novel green technology as an alternative to conventional chitin extraction and to design environmentally friendly food packaging based on chitosan.

Chitinase Chit62J4 Essential for Chitin Processing by Human Microbiome Bacterium Clostridium paraputrificum J4

Commensal bacterium Clostridium paraputrificum J4 produces several extracellular chitinolytic enzymes including a 62 kDa chitinase Chit62J4 active toward 4-nitrophenyl N,N'-diacetyl-β-d-chitobioside (pNGG). We characterized the crude enzyme from bacterial culture fluid, recombinant enzyme rChit62J4, and its catalytic domain rChit62J4cat. This major chitinase, securing nutrition of the bacterium in the human intestinal tract when supplied with chitin, has a pH optimum of 5.5 and processes pNGG with K_m = 0.24 mM and k_cat = 30.0 s^-1. Sequence comparison of the amino acid sequence of Chit62J4, determined during bacterial genome sequencing, characterizes the enzyme as a family 18 glycosyl hydrolase with a four-domain structure. The catalytic domain has the typical TIM barrel structure and the accessory domains-2x Fn3/Big3 and a carbohydrate binding module-that likely supports enzyme activity on chitin fibers. The catalytic domain is highly homologous to a single-domain chitinase of Bacillus cereus NCTU2. However, the catalytic profiles significantly differ between the two enzymes despite almost identical catalytic sites. The shift of pI and pH optimum of the commensal enzyme toward acidic values compared to the soil bacterium is the likely environmental adaptation that provides C. paraputrificum J4 a competitive advantage over other commensal bacteria.

Chitosan Oligosaccharide Ameliorates Metabolic Syndrome Induced by Overnutrition via Altering Intestinal Microbiota

Chitosan oligosaccharides (COS) play a prebiotic role in many ways, whereas its function on microbiota is not fully understood. In this study, the effects of COS on metabolic syndrome were initially investigated by testing changes in the physiological indicators after adding COS to the diet of mice with high fat (group H) and low fat (group L). The results showed that COS markedly inhibited the accumulation of body weight and liver fat induced by high-fat diet, as well as restored the elevated concentration of blood glucose and fasting insulin to normal levels. Next, changes of the murine intestinal microbiota were examined. The results exhibited that COS reduced with-in-sample diversity, while the between-sample microbial diversity enhanced. Specifically, COS enriched Clostridium paraputrificum and Clostridium ramosum in the mice on a high-fat diet, while the abundance of Clostridium cocleatum was reduced. As a comparison, Parabacteroides goldsteinii and Bacteroides uniformis increased their abundance in response to COS in the low-fat diet group. Noticeably, a large amount of Akkermansia muciniphila was enriched in both high-fat or low-fat diet groups. Among the differential fecal bacteria, Clostridium ramosume was found to be positively interacted with Faecalibacterim prausnitzii and Clostridium paraputrificum; Clostridium paraputrificum had a positive interactions with Lactococcus chungangensis and Bifidobacterium mongoliense, suggesting that COS probably ameliorate metabolic syndrome through the microbiota in view of the lipid-lowering effects of these interacted bacteria. Furthermore, the gene expression data revealed that COS improved the functions related to intestinal barrier and glucose transport, which could be the trigger and consequence of the variations in gut microbiota induced by COS. Additionally, correlation analysis found that intestinal bacteria are related to physiological parameters, which further supports the mediating role of gut microbiota in the beneficial effect of COS. In summary, our research results provide new evidence for the prebiotic effects of COS.

Therapeutic Properties of Edible Mushrooms and Herbal Teas in Gut Microbiota Modulation

Edible mushrooms are functional foods and valuable but less exploited sources of biologically active compounds. Herbal teas are a range of products widely used due to the therapeutic properties that have been demonstrated by traditional medicine and a supplement in conventional therapies. Their interaction with the human microbiota is an aspect that must be researched, the therapeutic properties depending on the interaction with the microbiota and the consequent fermentative activity. Modulation processes result from the activity of, for example, phenolic acids, which are a major component and which have already demonstrated activity in combating oxidative stress. The aim of this mini-review is to highlight the essential aspects of modulating the microbiota using edible mushrooms and herbal teas. Although the phenolic pattern is different for edible mushrooms and herbal teas, certain non-phenolic compounds (polysaccharides and/or caffeine) are important in alleviating chronic diseases. These specific functional compounds have modulatory properties against oxidative stress, demonstrating health-beneficial effects in vitro and/or In vivo. Moreover, recent advances in improving human health via gut microbiota are presented. Plant-derived miRNAs from mushrooms and herbal teas were highlighted as a potential strategy for new therapeutic effects.

Reflections on the Use of an Invertebrate Chordate Model System for Studies of Gut Microbial Immune Interactions

The functional ecology of the gastrointestinal tract impacts host physiology, and its dysregulation is at the center of various diseases. The immune system, and specifically innate immunity, plays a fundamental role in modulating the interface of host and microbes in the gut. While humans remain a primary focus of research in this field, the use of diverse model systems help inform us of the fundamental principles legislating homeostasis in the gut. Invertebrates, which lack vertebrate-style adaptive immunity, can help define conserved features of innate immunity that shape the gut ecosystem. In this context, we previously proposed the use of a marine invertebrate, the protochordate Ciona robusta, as a novel tractable model system for studies of host-microbiome interactions. Significant progress, reviewed herein, has been made to fulfill that vision. We examine and review discoveries from Ciona that include roles for a secreted immune effector interacting with elements of the microbiota, as well as chitin-rich mucus lining the gut epithelium, the gut-associated microbiome of adults, and the establishment of a large catalog of cultured isolates with which juveniles can be colonized. Also discussed is the establishment of methods to rear the animals germ-free, an essential technology for dissecting the symbiotic interactions at play. As the foundation is now set to extend these studies into the future, broadening our comprehension of how host effectors shape the ecology of these microbial communities in ways that establish and maintain homeostasis will require full utilization of "multi-omics" approaches to merge computational sciences, modeling, and experimental biology in hypothesis-driven investigations.

Dietary Supplements Intended for Children--Proposed Classification of Products Available on the Market

Lately, it has been observed that the variety of dietary supplements is rapidly growing. The aim of the study is to extend the classification of dietary supplements (DSs) intended for children above the age of 3, as well as to categorize the ingredients used to manufacture such products. Three hundred fifteen dietary supplements intended for children from 3 to 12 years old, available on the Polish market, were chosen. Evaluation of product specifications provided by the producers, which included lists of ingredients as well as health and nutrition claims found on labels or online, was conducted. Among the available products, one can distinguish supplements with overall health effects used to supplement the diet (such as multivitamin supplements) as well as products for specific conditions, which can be divided into a total of 10 groups of products. Substances that can be found in dietary supplements were also systematized and divided into eight categories, which constitute a division of DSs active ingredients. The results of this research are an extension to the already existing Polish and European classification, which can be applied to classify products intended for children as well as for adults.

Intestinal Population in Host with Metabolic Syndrome during Administration of Chitosan and Its Derivatives

Chitosan and its derivatives can alleviate metabolic syndrome by different regulation mechanisms, phosphorylation of AMPK (AMP-activated kinase) and Akt (also known as protein kinase B), suppression of PPAR-γ (peroxisome proliferator-activated receptor-γ) and SREBP-1c (sterol regulatory element–binding proteins), and translocation of GLUT4 (glucose transporter-4), and also the downregulation of fatty-acid-transport proteins, fatty-acid-binding proteins, fatty acid synthetase (FAS), acetyl-CoA carboxylase (acetyl coenzyme A carboxylase), and HMG-CoA reductase (hydroxy methylglutaryl coenzyme A reductase). The improved microbial profiles in the gastrointestinal tract were positively correlated with the improved glucose and lipid profiles in hosts with metabolic syndrome. Hence, this review will summarize the current literature illustrating positive correlations between the alleviated conditions in metabolic syndrome hosts and the normalized gut microbiota in hosts with metabolic syndrome after treatment with chitosan and its derivatives, implying that the possibility of chitosan and its derivatives to serve as therapeutic application will be consolidated. Chitosan has been shown to modulate cardiometabolic symptoms (e.g., lipid and glycemic levels, blood pressure) as well as gut microbiota. However, the literature that summarizes the relationship between such metabolic modulation of chitosan and prebiotic-like effects is limited. This review will discuss the connection among their structures, biological properties, and prebiotic effects for the treatment of metabolic syndrome. Our hope is that future researchers will consider the prebiotic effects as significant contributors to the mitigation of metabolic syndrome.