Encapsulation of bioactive peptides: a strategy to improve the stability, protect the nutraceutical bioactivity and support their food applications

Enhancing storage stability of pea peptides through encapsulation in maltodextrin and gum tragacanth via monitoring scavenge ability to free radicals

Pea peptides can lead to degradation through oxidation, deamidation, hydrolysis, or cyclization during production, processing, and storage, which in turn limit their broader application. To stabilize pea peptides, this study employed spray drying technology to create a pea peptide micro-encapsule using maltodextrin, gum tragacanth, and pea peptides. Four key factors, including polysaccharide ratio, glycopeptide ratio, solid-liquid ratio, and inlet temperature, were optimized to enhance the antioxidant properties of the pea peptide micro-encapsule. The results indicated that the utilization of maltodextrin and gum tragacanth significantly improves the storage stability and antioxidant activity of pea peptides. Moreover, optimal storage stability for pea peptides was achieved with a polysaccharide ratio of 9:1, a glycopeptide ratio of 10:1, a solid-liquid ratio of 4:40, and an inlet temperature of 180 °C. After 60 days of storage, the encapsulated pea peptides maintained 70.22 %, 25.19 %, and 40.32 % for scavenging abilities to hydroxyl radical, superoxide anion, and ABTS radical, respectively. In contrast, the unencapsulated pea peptides showed a decline to 47.02 %, 0 %, and 24.46 % in the same antioxidant activities after storage. These findings underscore the potential of spray drying technology to enhance the functional properties of pea peptides for various applications.

Challenges in Peptide Solubilization - Amyloids Case Study

Peptide science has been a rapidly growing research field because of the enormous potential application of these biocompatible and bioactive molecules. However, many factors limit the widespread use of peptides in medicine, and low solubility is among the most common problems that hamper drug development in the early stages of research. Solubility is a crucial, albeit poorly understood, feature that determines peptide behavior. Several different solubility predictors have been proposed, and many strategies and protocols have been reported to dissolve peptides, but none of them is a one-size-fits-all method for solubilization of even the same peptide. In this review, we look for the reasons behind the difficulties in dissolving peptides, analyze the factors influencing peptide aggregation, conduct a critical analysis of solubilization strategies and protocols available in the literature, and give some tips on how to deal with the so-called difficult sequences. We focus on amyloids, which are particularly difficult to dissolve and handle such as amyloid beta (Aβ), insulin, and phenol-soluble modulins (PSMs).

Recombinant scFv-Fc Anti-kallikrein 7 Antibody-Loaded Thermosensitive Hydrogels Against Skin Desquamation Disorders

Human tissue kallikrein-related peptidase 7 (KLK7) is a serine protease implicated in the physiology of skin desquamation, and its uncontrolled activity can lead to chronic diseases such as psoriasis, atopic dermatitis, and Netherton syndrome. For this reason, kallikrein 7 has been identified as a potential therapeutic target. This work aimed to evaluate Pluronic (PL) hydrogels as topical carriers of four specific scFv-Fc antibodies to inhibit KLK7. The hydrogels comprised PL F127 (30% w/v) alone and a binary F127/P123 (28-2% w/v) system. Each formulation was loaded with 1 μg/mL of each antibody and characterized by physicochemical and pharmaceutical techniques, considering antibody-micelle interactions and hydrogel behavior as smart delivery systems. Results showed that the antibodies were successfully loaded into the PL-based systems, and the sol-gel transition temperature was shifted to high values after the P123 addition. The antibodies released from the gels preserved their rheological properties (G' > G'', 35- to 41-fold) and inhibitory activity against KLK7, even after 24 h. This work presented potential agents targeting KLK7 that may provide strategies for treating skin abnormalities.

Selenium-Chelating Peptide Derived from Wheat Gluten: In Vitro Functional Properties

The efficacy of selenium-chelating polypeptides derived from wheat protein hydrolysate (WPH-Se) includes enhancing antioxidant capacity, increasing bioavailability, promoting nutrient absorption, and improving overall health. This study aimed to enhance the bioavailability and functional benefits of exogenous selenium by chelating with wheat gluten protein peptides, thereby creating bioactive peptides with potentially higher antioxidant capabilities. In this study, WPH-Se was prepared with wheat peptide and selenium at a mass ratio of 2:1, under a reaction system at pH 8.0 and 80 °C. The in vitro antioxidant activity of WPH-Se was evaluated by determining the DPPH, OH, and ABTS radical scavenging rate and reducing capacity under different conditions, and the composition of free amino acids and bioavailability were also investigated at various digestion stages. The results showed that WPH-Se possessed significant antioxidant activities under different conditions, and DPPH, OH, and ABTS radical scavenging rates and reducing capacity remained high at different temperatures and pH values. During gastrointestinal digestion in vitro, both the individual digestate and the final digestate maintained high DPPH, OH, and ABTS radical scavenging rates and reducing capacity, indicating that WPH-Se was able to withstand gastrointestinal digestion and exert antioxidant effects. Post-digestion, there was a marked elevation in tryptophan, cysteine, and essential amino acids, along with the maintenance of high selenium content in the gastrointestinal tract. These findings indicate that WPH-Se, with its enhanced selenium and amino acid profile, serves as a promising ingredient for dietary selenium and antioxidant supplementation, potentially enhancing the nutritional value and functional benefits of wheat gluten peptides.

Encapsulation of Tenebrio molitor Hydrolysate with DPP-IV Inhibitory Activity by Electrospraying and Spray-Drying

This study investigates the encapsulation of Tenebrio molitor hydrolysate exhibiting DPP-IV inhibitory activity by spray-drying and electrospraying techniques. First, we optimized the feed formulation and processing conditions required to obtain nano-microcapsules by electrospraying when using Arabic gum as an encapsulating agent and pullulan and Tween 20 as additives. The optimum formulation was also dried by spray-drying, where the removal of the additives was also assayed. Morphology analysis reveals that electrosprayed capsules have a smaller size (1.2 ± 0.5 µm vs. 12.4 ± 8.7 µm) and greater uniformity compared to those obtained by spray-drying. Regarding the surface nitrogen content and DPP-IV inhibitory activity, our results show no significant difference between the electrosprayed capsules and spray-dried capsules containing additives (IC50 of ~1.5 mg protein/mL). Therefore, it was concluded that adding additives during spray-drying allows for a similar encapsulation efficiency and reduced degradation during processing, as achieved by electrospraying technique but providing higher productivity. On the other hand, spray-dried capsules without additives displayed a higher surface nitrogen content percentage, which was mainly due to the absence of Tween 20 in the feed formulation. Consequently, these capsules presented a higher IC50 value (IC50 of 1.99 ± 0.03 mg protein/mL) due to the potential degradation of surface-exposed peptides.

Encapsulation of short-chain bioactive peptides (BAPs) for gastrointestinal delivery: a review

The majority of known peptides with high bioactivity (BAPs) such as antihypertensive, antidiabetic, antioxidant, hypocholesterolemic, anti-inflammatory and antimicrobial actions, are short-chain sequences of less than ten amino acids. These short-chain BAPs of varying natural and synthetic origin must be bioaccessible to be capable of being adsorbed systemically upon oral administration to show their full range of bioactivity. However, in general, in vitro and in vivo studies have shown that gastrointestinal digestion reduces BAPs bioactivity unless they are protected from degradation by encapsulation. This review gives a critical analysis of short-chain BAP encapsulation and performance with regard to the oral delivery route. In particular, it focuses on short-chain BAPs with antihypertensive and antidiabetic activity and encapsulation methods via nanoparticles and microparticles. Also addressed are the different wall materials used to form these particles and their associated payloads and release kinetics, along with the current challenges and a perspective of the future applications of these systems.

Essential considerations towards development of effective nasal antibiotic formulation: features, strategies, and future directions

INTRODUCTION

Intranasal antibiotic products are gaining popularity as a promising method of administering antibiotics, which provide numerous benefits, e.g. enhancing drug bioavailability, reducing adverse effects, and potentially minimizing resistance threats. However, some issues related to the antibiotic substances and nasal route challenges must be addressed to prepare effective formulations.

AREAS COVERED

This review focuses on the valuable points of nasal delivery as an alternative route for administering antibiotics, coupled with the challenges in the nasal cavity that might affect the formulations. Moreover, this review also highlights the application of nasal delivery to introduce antibiotics for local therapy, brain targeting, and systemic effects that have been conducted. In addition, this viewpoint provides strategies to maintain antibiotic stability and several crucial aspects to be considered for enabling effective nasal formulation.

EXPERT OPINION

In-depth knowledge and understanding regarding various key considerations with respect to the antibiotic substances and nasal route delivery requirement in preparing effective nasal antibiotic formulation would greatly improve the development of nasally administered antibiotic products, enabling better therapeutic outcomes of antibiotic treatment and establishing appropriate use of antibiotics, which in turn might reduce the chance of antibiotic resistance and enhance patient comfort.

Filamentous fungal pellets as a novel and sustainable encapsulation matrix for exogenous bioactive compounds

Edible filamentous fungi (FF) are considered sustainable food materials given their rich nutrient profile and low carbon and water footprints during production. The current study evaluated FF biomass as a natural encapsulation system for exogenous bioactive compounds and as a model system to investigate the complex food matrix-micronutrient interactions during in vitro digestion. Our objective was to compare the fungal pellet, as a multicellular encapsulation system, with single yeast cell-based carriers in terms of loading and release of curcumin, a model compound. The results suggest that the curcumin encapsulation efficiency was similar in single yeast cells and fungal hyphal cells. A vacuum treatment used to facilitate the infusion of curcumin into yeast or fungal cells also enabled rapid internalization of yeast cells into the fungal pellet matrix. Compared to the single-cell encapsulation system, the multicellular systems modified the release kinetics of curcumin during in vitro digestion by eliminating the initial rapid release and reducing the overall release rate of curcumin in the small intestinal phase. These results provide a deeper understanding of the effect of natural edible structures on the bioaccessibility of micronutrients, and demonstrate the potential of using FF biomass as functional food materials.

Identification of the Bioavailable Peptidome of Chia Protein Hydrolysate and the In Silico Evaluation of Its Antioxidant and ACE Inhibitory Potential

The incorporation of novel, functional, and sustainable foods in human diets is increasing because of their beneficial effects and environmental-friendly nature. Chia (Salvia hispanica L.) has proved to be a suitable source of bioactive peptides via enzymatic hydrolysis. These peptides could be responsible for modulating several physiological processes if able to reach the target organ. The bioavailable peptides contained in a hydrolysate obtained with Alcalase, as functional foods, were identified using a transwell system with Caco-2 cell culture as the absorption model. Furthermore, 20 unique peptides with a molecular weight lower than 1000 Da and the higher statistical significance of the peptide-precursor spectrum match (-10 log P) were assessed by in silico tools to suggest which peptides could be those exerting the demonstrated bioactivity. From the characterized peptides, considering the molecular features and the results obtained, the peptides AGDAHWTY, VDAHPIKAM, PNYHPNPR, and ALPPGAVHW are anticipated to be contributing to the antioxidant and/or ACE inhibitor activity of the chia protein hydrolysates.

Food bioactive peptides: functionality beyond bitterness

Bitter taste is an aversive taste because it is unconsciously associated with toxic compounds. However, a considerable variability in bitter sensitivity exists in those who have the genetic polymorphism for bitter taste receptors (TAS2Rs). Besides the oral cavity, TAS2Rs are present in many body tissues, including the gastrointestinal tract; therefore, they are crucial players both in the gustatory/hedonic system and in the homeostatic system, triggering numerous biological responses, including adipogenesis, carcinogenesis, or immunity. Bitter-tasting compounds are widely distributed in plant and animal foods and belong to many chemical classes. In this study, the evidence was reviewed on bitter peptides, considering the food sources, their formation in food under different processing and storage conditions and in the gastrointestinal tract during digestion, as well as their biological activities. Bitterness associated with peptides is due to the presence of hydrophobic amino acids in the C-terminus. The current literature mainly explores the enzymes and hydrolysis conditions, with the aim of reducing the formation of bitter peptides in hydrolysate preparation or food. Few studies highlight the bioactivity (namely, antihypertensive, antidiabetic, antioxidant, or immunity boosting), besides the bitterness. However, encapsulation of bitter peptides has been tentatively used to develop antihypertensive and antidiabetic supplements. In the era of personalized nutrition and precision medicine, the evidence available suggests the opportunity to use bitter bioactive peptides as functional ingredients in food. Such types of food may modulate a plethora of physiological mechanisms by targeting TAS2Rs in the gastrointestinal tract, thus modulating appetite sensations or gastrointestinal motility and discomfort according to individual nutritional needs and goals. More studies are needed to optimize the technological strategies to target TAS2Rs by bitter bioactive peptides, improve their stability in food, and validate the biological efficacy through well-designed in vivo studies.

Development of "Smart Foods" for health by nanoencapsulation: Novel technologies and challenges

Importance of nanotechnology may be seen by penetration of its application in diverse areas including the food sector. With investigations and advancements in nanotechnology, based on feedback from these diverse areas, ease, and efficacy are also increasing. The food sector may use nanotechnology to encapsulate smart foods for increased health, wellness, illness prevention, and effective targeted delivery. Such nanoencapsulated targeted delivery systems may further add to the economic and nutritional properties of smart foods like stability, solubility, effectiveness, safeguard against disintegration, permeability, and bioavailability of smart/bioactive substances. But in the way of application, the fabrication of nanomaterials/nanostructures has several challenges which range from figuring out the optimal technique for obtaining them to determining the most suitable form of nanostructure for a bioactive molecule of interest. This review precisely addresses concepts, recent advances in fabrication techniques as well as current challenges/glitches of nanoencapsulation with special reference to smart foods/bioactive components. Since dealing with food materials also raises the quest for safety and regulatory norms a brief overview of the safety and regulatory aspects of nanomaterials/nanoencapsulation is also presented.

Production and identification of immunomodulatory peptides in intestine cells obtained from hemp industrial by-products

Hemp seeds have attracted the interest of the food industry recently, to be employed as functional food, considering their nutritional composition, highlighting the high content and quality of the proteins. In this study, ten hemp protein hydrolysates (HPHs) were obtained by enzymatic hydrolysis with two food-grade proteases from a hemp protein isolate and the inflammatory properties were evaluated in Caco-2 cell line. To this end, the gene expression and the release of proinflammatory and anti-inflammatory cytokines by Caco-2 cells stimulated with bacterial lipopolysaccharide and treated with HPHs at concentrations of 50 and 100 μg/mL were analyzed. The peptides contained in each HPH were identified and those with higher quality of the match in the spectrum were subjected to in silico analyses to determine which peptides were bioactive and contributing to the immunomodulatory activity of the hydrolysates. The results suggest that the immunomodulatory properties of these HPHs could have a beneficial effect at the level of the intestinal epithelium. The HPH20A and HPH60A + 15F exerted high immunomodulatory properties based on the cytokine levels release. The oligopeptides MAEKEGFEWVSF and GLHLPSYTNTPQLVYIVK were proposed as the most active ones. The potential of these peptides as nutraceuticals to prevent or pretreat intestinal inflammation is promising, though requires validation by in vivo assays.

Revisiting the influence of pH on 1JCαH and chemical shifts of glycine and alanine short oligopeptides

The pH dependence of several NMR parameters of glycine and alanine short oligopeptides has been reported previously in different studies. Here we have thoroughly examined, summarized and demonstrated the dependences of 1H, 13C and 15N chemical shifts and protonation states of amino acids using two-dimensional NMR experiments. Nevertheless, 1JCαH one bond spin-spin coupling constants are more informative and convenient for determination of the position and protonation state of glycine and alanine residue in the oligopeptide chain. In particular, for various oligopeptides (up to six residues), it was shown that the pH dependence of 1JCαH of N-terminal glycine and alanine residues is larger than that of C-terminal groups, and in backbone residues, it is not influenced by pH and only slightly depends on the position of the amino acid residue in the chain.

Chitosan Microparticles Enhance the Intestinal Release and Immune Response of an Immune Stimulant Peptide in Oncorhynchus mykiss

The aquaculture industry is constantly increasing its fish production to provide enough products to maintain fish consumption worldwide. However, the increased production generates susceptibility to infectious diseases that cause losses of millions of dollars to the industry. Conventional treatments are based on antibiotics and antivirals to reduce the incidence of pathogens, but they have disadvantages, such as antibiotic resistance generation, antibiotic residues in fish, and environmental damage. Instead, functional foods with active compounds, especially antimicrobial peptides that allow the generation of prophylaxis against infections, provide an interesting alternative, but protection against gastric degradation is challenging. In this study, we evaluated a new immunomodulatory recombinant peptide, CATH-FLA, which is encapsulated in chitosan microparticles to avoid gastric degradation. The microparticles were prepared using a spray drying method. The peptide release from the microparticles was evaluated at gastric and intestinal pH, both in vitro and in vivo. Finally, the biological activity of the formulation was evaluated by measuring the expression of il-1β, il-8, ifn-γ, Ifn-α, and mx1 in the head kidney and intestinal tissues of rainbow trout (Oncorhynchus mykiss). The results showed that the chitosan microparticles protect the CATH-FLA recombinant peptide from gastric degradation, allowing its release in the intestinal portion of rainbow trout. The microparticle-protected CATH-FLA recombinant peptide increased the expression of il-1β, il-8, ifn-γ, ifn-α, and mx1 in the head kidney and intestine and improved the antiprotease activity in rainbow trout. These results suggest that the chitosan microparticle/CATH-FLA recombinant peptide could be a potential prophylactic alternative to conventional antibiotics for the treatment of infectious diseases in aquaculture.

Effect of Heat Treatment on Protein Self-Digestion in Ruminants' Milk

This study investigated whether heat treatments (raw, 63 °C for 30 min, and 85 °C for 5 min) affect protein hydrolysis by endogenous enzymes in the milk of ruminants (bovine, ovine, and caprine) using a self-digestion model. Self-digestion consisted of the incubation for six hours at 37 °C of the ruminants' milk. Free amino group concentration was measured by the o-phthaldialdehyde method, and peptide sequences were identified by chromatography-mass spectrometry. Results showed that heat treatments prior to self-digestion decreased the free NH2 by 59% in bovine milk heated at 85 °C/5 min, and by 44 and 53% in caprine milk heated at 63 °C/30 min and 85 °C/5 min, respectively. However, after self-digestion, only new free amino groups were observed for the raw and heated at 63 °C/30 min milk. β-Casein was the most cleaved protein in the raw and heated at 63 °C/30 min bovine milk. A similar trend was observed in raw ovine and caprine milk. Self-digestion increased 6.8-fold the potential antithrombin peptides in the bovine milk heated at 63 °C/30 min. Enhancing bioactive peptide abundance through self-digestion has potential applications in the industry for functional products. Overall, heat treatments affected the free amino groups according to the species and heat treatment applied, which was reflected in the varying degrees of cleaved peptide bonds and peptides released during self-digestion.

Bioactive Peptides from Edible Mushrooms-The Preparation, Mechanisms, Structure-Activity Relationships and Prospects

Mushroom bioactive peptides (MBPs) are bioactive peptides extracted directly or indirectly from edible mushrooms. MBPs are known to have antioxidant, anti-aging, antibacterial, anti-inflammatory and anti-hypertensive properties, and facilitate memory and cognitive improvement, antitumour and anti-diabetes activities, and cholesterol reduction. MBPs exert antioxidant and anti-inflammatory effects by regulating the MAPK, Keap1-Nrf2-ARE, NF-κB and TNF pathways. In addition, MBPs exert antibacterial, anti-tumour and anti-inflammatory effects by stimulating the proliferation of macrophages. The bioactivities of MBPs are closely related to their molecular weights, charge, amino acid compositions and amino acid sequences. Compared with animal-derived peptides, MBPs are ideal raw materials for healthy and functional products with the advantages of their abundance of resources, safety, low price, and easy-to-achieve large-scale production of valuable nutrients for health maintenance and disease prevention. In this review, the preparation, bioactivities, mechanisms and structure-activity relationships of MBPs were described. The main challenges and prospects of their application in functional products were also discussed. This review aimed to provide a comprehensive perspective of MBPs.

Antioxidant Effect Assessment and Trans Epithelial Analysis of New Hempseed Protein Hydrolysates

Hempseed (Cannabis sativa) is one of the most promising sources of plant proteins. It contains approximately 24% (w/w) protein, and edestin accounts for approximately 60-80% (w/w) of its total proteins. In a framework of research aimed at fostering the proteins recovered from the press cake by-products generated after the extraction of hempseed oil, two hempseed protein hydrolysates (HH1 and HH2) were produced at an industrial level using a mixture of different enzymes from Aspergillus niger, Aspergillus oryzae, and Bacillus licheniformis for different times (5 h and 18 h). Using a combination of different direct antioxidant tests (DPPH, TEAC, FRAP, and ORAC assays, respectively), it has been demonstrated that HHs exert potent, direct antioxidant activity. A crucial feature of bioactive peptides is their intestinal bioavailability; for this reason, in order to solve this peculiar issue, the ability of HH peptides to be transported by differentiated human intestinal Caco-2 cells has been evaluated. Notably, by using mass spectrometry analysis (HPLC Chip ESI-MS/MS), the stable peptides transported by intestinal cells have been identified, and dedicated experiments confirmed that the trans-epithelial transported HH peptide mixtures retain their antioxidant activity, suggesting that these hempseed hydrolysates may be considered sustainable antioxidant ingredients to be exploited for further application, i.e., nutraceutical and/or food industries.

Encapsulation of Bioactive Peptides by Spray-Drying and Electrospraying

Bioactive peptides derived from enzymatic hydrolysis are gaining attention for the production of supplements, pharmaceutical compounds, and functional foods. However, their inclusion in oral delivery systems is constrained by their high susceptibility to degradation during human gastrointestinal digestion. Encapsulating techniques can be used to stabilize functional ingredients, helping to maintain their activity after processing, storage, and digestion, thus improving their bioaccessibility. Monoaxial spray-drying and electrospraying are common and economical techniques used for the encapsulation of nutrients and bioactive compounds in both the pharmaceutical and food industries. Although less studied, the coaxial configuration of both techniques could potentially improve the stabilization of protein-based bioactives via the formation of shell-core structures. This article reviews the application of these techniques, both monoaxial and coaxial configurations, for the encapsulation of bioactive peptides and protein hydrolysates, focusing on the factors affecting the properties of the encapsulates, such as the formulation of the feed solution, selection of carrier and solvent, as well as the processing conditions used. Furthermore, this review covers the release, retention of bioactivity, and stability of peptide-loaded encapsulates after processing and digestion.

Bioactive food-derived peptides for functional nutrition: Effect of fortification, processing and storage on peptide stability and bioactivity within food matrices

New challenges in food production and processing are appearing due to increasing global population and the purpose of achieving a sustainable food system. Bioactive peptides obtained from food proteins can be employed to prevent or pre-treat several diseases such as diabetes, cardiovascular diseases, inflammation, thrombosis, cancer, etc. Research on the bioactivity of protein hydrolysates is very extensive, especially in vitro tests, although there are also tests in animal models and in humans studies designed to verify their efficacy. However, there is very little published literature on the functionality of these protein hydrolysates as an ingredient in food matrices, as well as the effect that thermal or non-thermal processing, and storage may have on the bioactivity of these bioactive peptides. This review aims to summarize the published literature on protein hydrolysates as a functional ingredient including processing, storage and simulated gastrointestinal digestion regarding the bioactivity of these peptides inside food matrices.

Stability and bioactivity of peptides in food matrices based on processing conditions

Bioactive peptides (BPs) generated from food proteins can serve therapeutic purposes against degenerative and cardiovascular diseases such as inflammation, diabetes, and cancer. There are numerous reports on the in vitro, animal, and human studies of BPs, but not as much information on the stability and bioactivity of these peptides when incorporated in food matrices. The effects of heat and non-heat processing of the food products, and storage on the bioactivity of the BPs, are also lacking. To this end, we describe the production of BPs in this review, followed by the food processing conditions that affect their storage bioactivity in the food matrices. As this area of research is open for industrial innovation, we conclude that novel analytical methods targeting the interactions of BPs with other components in food matrices would be greatly significant while elucidating their overall bioactivity before, during and after processing.

Encapsulated Peptides and Proteins with an Effect on Satiety

The world scenario has undergone a nutritional transition in which some countries have left the reality of malnutrition and now face an epidemic of excess body weight. Researchers have been looking for strategies to reverse this situation. Peptides and proteins stand out as promising molecules with anti-obesity action. However, oral administration and passage through the gastrointestinal tract face numerous physiological barriers that impair their bioactive function. Encapsulation aims to protect the active substance and modify the action, one possibility of potentiating anti-obesity activity. Research with encapsulated peptides and proteins has demonstrated improved stability, delivery, controlled release, and increased bioactivity. However, it is necessary to explore how proteins and peptides affect weight loss and satiety, can impact the nutritional status of obesity, and how encapsulation can enhance the bioactive effects of these molecules. This integrative review aimed to discuss how the encapsulation of protein molecules impacts the nutritional status of obesity. From the studies selected following pre-established criteria, it was possible to infer that the encapsulation of proteins and peptides can contribute to greater efficiency in reducing weight gain, changes in adipose tissue function, and lower hormone levels that modulate appetite and body weight in animals with obesity.

Interactions between Soybean Trypsin Inhibitor and Chitosan in an Aqueous Solution

Supramolecular structures obtained from protein-polysaccharide association may be applied to encapsulate bioactive compounds or to improve the physical stability and texture properties of colloid-based products. In this study, the interaction of 0.1 wt% soybean trypsin inhibitor (STI) with different concentrations of chitosan (CS) in aqueous solutions was investigated under different pH by the analysis of state diagram, turbidity, zeta potential, spectroscopy, and microstructure; the protective effect of STI-CS complex coacervates on STI stability in simulated gastric juice was also discussed. The results suggested that interactions between STI and CS could form soluble/insoluble complexes mainly through hydrophobic interactions (pH 4.0) or electrostatic interactions (pH 6.0). The CD spectra showed that the secondary structure of STI did not change significantly when CS with the same charge was mixed with STI, and the secondary structure of STI was slightly changed when CS with the opposite charge was mixed with STI. Simulated gastric digestion experiments showed that the complex formed by non-covalent bonding had a protective effect on the active protein. This study provides information about the effect of different CS concentrations and pH values on the formation of complexes of CS and STI in an aqueous solution and provides theoretical references for the construction of supramolecular-structured carrier substances based on CS and STI.

Encapsulation of Bioactive Compounds for Food and Agricultural Applications

This review presents an updated scenario of findings and evolutions of encapsulation of bioactive compounds for food and agricultural applications. Many polymers have been reported as encapsulated agents, such as sodium alginate, gum Arabic, chitosan, cellulose and carboxymethylcellulose, pectin, Shellac, xanthan gum, zein, pullulan, maltodextrin, whey protein, galactomannan, modified starch, polycaprolactone, and sodium caseinate. The main encapsulation methods investigated in the study include both physical and chemical ones, such as freeze-drying, spray-drying, extrusion, coacervation, complexation, and supercritical anti-solvent drying. Consequently, in the food area, bioactive peptides, vitamins, essential oils, caffeine, plant extracts, fatty acids, flavonoids, carotenoids, and terpenes are the main compounds encapsulated. In the agricultural area, essential oils, lipids, phytotoxins, medicines, vaccines, hemoglobin, and microbial metabolites are the main compounds encapsulated. Most scientific investigations have one or more objectives, such as to improve the stability of formulated systems, increase the release time, retain and protect active properties, reduce lipid oxidation, maintain organoleptic properties, and present bioactivities even in extreme thermal, radiation, and pH conditions. Considering the increasing worldwide interest for biomolecules in modern and sustainable agriculture, encapsulation can be efficient for the formulation of biofungicides, biopesticides, bioherbicides, and biofertilizers. With this review, it is inferred that the current scenario indicates evolutions in the production methods by increasing the scales and the techno-economic feasibilities. The Technology Readiness Level (TRL) for most of the encapsulation methods is going beyond TRL 6, in which the knowledge gathered allows for having a functional prototype or a representative model of the encapsulation technologies presented in this review.

Formulation Strategies to Improve the Stability and Handling of Oral Solid Dosage Forms of Highly Hygroscopic Pharmaceuticals and Nutraceuticals

Highly hygroscopic pharmaceutical and nutraceutical solids are prone to significant changes in their physicochemical properties due to chemical degradation and/or solid-state transition, resulting in adverse effects on their therapeutic performances and shelf life. Moisture absorption also leads to excessive wetting of the solids, causing their difficult handling during manufacturing. In this review, four formulation strategies that have been employed to tackle hygroscopicity issues in oral solid dosage forms of pharmaceuticals/nutraceuticals were discussed. The four strategies are (1) film coating, (2) encapsulation by spray drying or coacervation, (3) co-processing with excipients, and (4) crystal engineering by co-crystallization. Film coating and encapsulation work by acting as barriers between the hygroscopic active ingredients in the core and the environment, whereas co-processing with excipients works mainly by adding excipients that deflect moisture away from the active ingredients. Co-crystallization works by altering the crystal packing arrangements by introducing stabilizing co-formers. For hygroscopic pharmaceuticals, coating and co-crystallization are the most commonly employed strategies, whereas coating and encapsulation are popular for hygroscopic nutraceuticals (e.g., medicinal herbs, protein hydrolysates). Encapsulation is rarely applied on hygroscopic pharmaceuticals, just as co-crystallization is rarely used for hygroscopic nutraceuticals. Therefore, there is potential for improved hygroscopicity reduction by exploring beyond the traditionally used strategy.

The current research status and strategies employed to modify food-derived bioactive peptides

The ability of bioactive peptides to exert biological functions has mainly contributed to their exploitation. The exploitation and utilization of these peptides have grown tremendously over the past two decades. Food-derived peptides from sources such as plant, animal, and marine proteins and their byproducts constitute a more significant portion of the naturally-occurring peptides that have been documented. Due to their high specificity and biocompatibility, these peptides serve as a suitable alternative to pharmacological drugs for treating non-communicable diseases (such as cardiovascular diseases, obesity, and cancer). They are helpful as food preservatives, ingredients in functional foods, and dietary supplements in the food sector. Despite their unique features, the application of these peptides in the clinical and food sector is to some extent hindered by their inherent drawbacks such as toxicity, bitterness, instability, and susceptibility to enzymatic degradation in the gastrointestinal tract. Several strategies have been employed to eliminate or reduce the disadvantages of peptides, thus enhancing the peptide bioactivity and broadening the opportunities for their applications. This review article focuses on the current research status of various bioactive peptides and the strategies that have been implemented to overcome their disadvantages. It will also highlight future perspectives regarding the possible improvements to be made for the development of bioactive peptides with practical uses and their commercialization.