α-Lactalbumin Self-Assembled Nanoparticles with Various Morphologies, Stiffnesses, and Sizes as Pickering Stabilizers for Oil-in-Water Emulsions and Delivery of Curcumin

Chitosan-gelatin composite hydrogel antibacterial film for food packaging

Antibacterial hydrogel film can serve as food packaging materials to prevent bacteria growth and spread, thereby extending shelf life and improve food safety. In this study, an efficient antibacterial hydrogel film (CLG) was prepared with chitosan, lysine, and gelatin. The light transmission of the CLG hydrogel film was over 80 % in the visible region, facilitating the observation of chicken breast storage conditions. Additionally, the swelling ratios of the hydrogel films decreased with increasing gelatin concentration, from 145.7 g/g (CLG1) to 92.6 g/g (CLG2) and 81.5 g/g (CLG3). This reduction was attributed to the denser network structure formed by the interaction between gelatin and the CL polymer. The Scanning Electron Microscopy (SEM) showed that the water-absorbed CLG hydrogel had a unique sponge shape. Moreover, the CLG hydrogel film exhibits high antibacterial activity against Escherichia coli (E. coli) and Staphylococcus aureus (S. aureus). In a practical storage experiment, the CLG hydrogel film extended the shelf life of chicken breast by up to 4 days compared to untreated samples, while effectively reducing total volatile basic nitrogen (TVB-N) levels. This hydrogel film is expected to become a promising food packaging material.

Quercetin encapsulation and release using rapid CO2-responsive rosin-based surfactants in Pickering emulsions

Emulsion-based delivery systems are extensively employed for encapsulating functional active ingredients, protecting them from degradation, and enhancing bioavailability and release efficiency. Here, a CO2-responsive surfactant synthesized from rosin displays rapid responsiveness to CO2 at room temperature, transitioning reversibly switches between active and inactive states multiple times. The dual tertiary amines on the rosin rigid structure contributes to its CO2 sensitivity. When in its active cationic form, in conjunction with silica nanoparticles, it exhibits desired Pickering emulsification performance across various oil phases. In the Pickering emulsion loaded with quercetin, the encapsulation efficiency and loading efficiency reached 80.50% and 0.69%, respectively, with stability lasting at least 30 days. The system provides robust protection for quercetin against external factors, such as UV and heat, revealing sustained release effects. This study investigated the potential of using rosin-based CO2-responsive surfactants alongside nanoparticles to design stable Pickering emulsion systems for active substance encapsulation and sustained release.

Recent advances in dietary polyphenols (DPs): antioxidant activities, nutrient interactions, delivery systems, and potential applications

Dietary polyphenols (DPs) have garnered growing interest because of their potent functional properties and health benefits. Nevertheless, the antioxidant capabilities of these substances are compromised by their multifarious structural compositions. Furthermore, most DPs are hydrophobic and unstable when subjected to light, heat, and varying pH conditions, restricting their practical application. Delivery systems based on the interactions of DPs with food constituents such as proteins, polypeptides, polysaccharides, and metal ions are being created as a viable option to improve the functional activities and bioavailability of DPs. In this review, the latest discoveries on the dietary sources, structure-antioxidant activity relationships, and interactions with nutrients of DPs are discussed. It also innovatively highlights the application progress of polyphenols and their green nutraceutical delivery systems. The conclusion drawn is that the various action sites and structures of DPs are beneficial for predicting and designing polyphenols with enhanced antioxidant attributes. The metal complexation of polyphenols and green encapsulation systems display promising outcomes for stabilizing DPs during food processing and in vivo digestion. In the future, more novel targeted delivery systems of DPs for nutrient fortification and intervention should be developed. To expand their usage in customized food products, they should meet the requirements of specific populations for personalized food and nutrition.

Pectin-based cinnamon essential oil Pickering emulsion film with two-sided differential wettability: A major role in the spatial distribution of microdroplets

Pickering emulsions have attracted much attention as a novel emulsifying technology. This research to explore Zein-Citrus pectin nanoparticles stabilized cinnamon essential oil (CEO) Pickering emulsion (ZCCPEs) for constructing Pickering emulsion edible film (PEF). Unlike traditional research, which focuses on antibacterial and antioxidant activities, our research examined the physical properties of PEF, specifically changes in wettability. The results show that PEF has better transparency and tensile strength than the pectin alone direct emulsion film (PAEF), and the spatial distribution of Pickering emulsion droplets gives different wettability on both sides of PEF. The partially hydrophobic upside has important application value in food packaging. At the same time, the PEF is biodegradable and environmentally non-polluting. The edible film loaded with essential oils, developed based on the Pickering stabilization mechanism in this study, possesses several desirable characteristics for potential used as bioactive packaging films in food applications.

Influence of divalent metal cations on α-lactalbumin fibril formation

The effect of binding of divalent metal cations (Ca2+, Cu2+, Mg2+, Mn2+, Zn2+) on the kinetics of fibril formation of bovine α-lactalbumin at acidic conditions is considered. The kinetic parameters of the process were determined using a thioflavin T fluorescence assay. The DSC thermograms of bovine α-lactalbumin in the presence and absence of cations were recorded. The duration of the lag period correlates with the changes in the thermal stability of the molten globule of the protein in the presence of cations. The final thioflavin T fluorescence intensity after formation of the mature fibrils decreases under the influence of calcium ions which strongly bind to the monomeric protein, and increases in solutions containing copper and especially zinc. These ions seem to accelerate secondary nucleation processes and change the fibril morphology, which was confirmed by atomic force microscopy imaging.

Development, Stability, and In Vitro/In Vivo Studies of Volatile Oil Pickering Emulsion Stabilized by Modified Amber

Volatile oil stabilization strategies based on encapsulation with a large number of excipients limit further applications. The primary objective of this study is to improve the stability of volatile oils using Pickering emulsion (PE) stabilized by Chinese medicinal powder based on the principle of "integrating drug and excipient". Modified amber was acquired through surface modification, and a stable oil-in-water PE loaded with Acorus tatarinowii volatile oil (ATVO) was constructed from modified amber. The stability, including the peroxide value (PV), malondialdehyde (MDA) content, and the content and composition of volatile components in modified amber-PE (MAPE) under intense light exposure, was analyzed deeply. In addition, the in vitro release and pharmacokinetics of MAPE and ATVO were investigated. The results demonstrate that the PV and MDA content in MAPE were significantly lower than in free ATVO, and the content and composition of volatile components in MAPE were closer to those in untreated ATVO. The release kinetics of β-asarone and α-asarone in MAPE demonstrated rapid and higher release, and pharmacokinetic studies show that MAPE has better bioavailability. This research provides a distinctive Chinese medicine solution to address the vaporization of volatile oil in solid formulations.

Natural Gastrointestinal Stable Pea Albumin Nanomicelles for Capsaicin Delivery and Their Effects for Enhanced Mucus Permeability at Small Intestine

Natural nanodelivery systems are highly desirable owing to their biocompatibility and biodegradability. However, these delivery systems face challenges from potential degradation in the harsh gastrointestinal environment and limitations imposed by the intestinal mucus barrier, reducing their oral delivery efficacy. Here, gastrointestinal stable and mucus-permeable pea albumin nanomicelles (PANs) with a small particle size (36.42 nm) are successfully fabricated via pre-enzymatic hydrolysis of pea albumin isolate (PAI) using trypsin. Capsaicin (CAP) is used as a hydrophobic drug model and loaded in PAN with a loading capacity of 20.02 μg/mg. PAN exhibits superior intestinal stability, with a 40% higher CAP retention compared to PAI in simulated intestinal digestion. Moreover, PAN displays unrestricted movement in intestinal mucus and can effectively penetrate it, since it increases the mucus permeability of CAP by 2.5 times, indicating an excellent ability to overcome the mucus barrier. Additionally, PAN enhances the cellular uptake and transcellular transport of CAP with endoplasmic reticulum/Golgi and Golgi/plasma membrane pathways involved in the transcytosis and exocytosis. This study suggests that partially enzymatically formed PAN may be a promising oral drug delivery system, effectively overcoming the harsh gastrointestinal environment and mucus barrier to improve intestinal absorption and bioavailability of hydrophobic bioactive substances.

Nanoparticle delivery systems of functional substances for precision nutrition

Foodborne functional substances have received much attention for their functional benefits in health and disease. However, these substances are easily affected by the adverse environment during production, transportation, or storage. They will also be damaged by the gastric environment and limited by the mucosal barrier after entering the human body, thus affecting the bioavailability of functional substances in the body. The construction of nanoparticle delivery systems is helpful to protect the biological activity of functional substances and improve their solubility, stability, and absorption of substances. Responsive delivery systems help control the release of functional substances in specific environments and targeted sites to achieve nutritional intervention, disease prevention, and treatment. In this chapter, the main types of foodborne functional substances and their commonly used delivery systems were reviewed, and the application of delivery systems in precision nutrition was described from the aspects of environmental stimuli-responsive delivery systems, site-specific delivery systems, and disease-targeted delivery systems.

Development of porous materials via protein/polysaccharides/polyphenols nanoparticles stabilized Pickering high internal phase emulsions for adsorption of Pb2+ and Cu2+ ions

The porous materials (PM) were prepared by the Pickering high internal phase emulsion (PHIPE) template. Firstly, the nanoparticles named as ZHMNPs or MZHMNPs were fabricated based on zein, Hohenbuehelia serotina polysaccharides and Malus baccata (Linn.) Borkh polyphenols without or with Maillard reaction, the average particle sizes and zeta potentials of which were distributed in a range of 718.1-979.4 nm and -21.6-25.2 mV. ZHMNPs possessed the relatively uniform spherical morphology, while MZHMNPs were irregular in shape. With ZHMNPs or MZHMNPs serving as the stabilizers, the PHIPEs were prepared, and exhibited the good viscoelasticity and excellent storage and freeze-thaw stabilities. Based on above PHIPEs template, the constructed PM possessed the large specific surface area and uniform pore structure. Through the investigations of adsorption performances, PM showed the outstanding adsorption capacities on Pb2+ and Cu2+ ions regardless of dissolving in deionized water or simulated gastrointestinal digestive fluid. Furthermore, the results also showed that the pH, temperature and adsorbent dosage had certain impacts on the adsorption performances of PM on Pb2+ and Cu2+ ions.

Cation Triggered Self-Assembly of α-Lactalbumin Nanotubes

Metal ions play a dual role in biological systems. Although they actively participate in vital life processes, they may contribute to protein aggregation and misfolding and thus contribute to development of diseases and other pathologies. In nanofabrication, metal ions mediate the formation of nanostructures with diverse properties. Here, we investigated the self-assembly of α-lactalbumin into nanotubes induced by coordination with metal ions, screened among the series Mn2+, Co2+, Ni2+, Zn2+, Cd2+, and Au3+. Our results revealed that the affinity of metal ions toward hydrolyzed α-lactalbumin peptides not only impacts the kinetics of nanotube formation but also influences their length and rigidity. These findings expand our understanding of supramolecular assembly processes in protein-based materials and pave the way for designing novel materials such as metallogels in biochip and biosensor applications.

The soybean lecithin-cyclodextrin-vitamin E complex nanoparticles stabilized Pickering emulsions for the delivery of β-carotene: Physicochemical properties and in vitro digestion

In this work, soybean lecithin (LC) was used to modify β-cyclodextrin (β-CD) with hydrophobic fat chains to become amphiphilic (LC-CD), and vitamin E (VE) was encapsulated in former modified β-CD complexes (LC-CD-VE), the new Pickering emulsions stabilized by LC-CD-VE and LC-CD complexes for the delivery of β-carotene (BC) were created. The surface tension, contact angle, zeta potential, and particle size were used to assess the changes in complexes nanoparticles at various pH values. Furthermore, LC-CD-VE has more promise as Pickering emulsion stabilizer than LC-CD because of the smaller particle size (271.11 nm), proper contact angle (58.02°), and lower surface tension (42.49 mN/m). The interactions between β-cyclodextrin, soybean lecithin, and vitamin E were confirmed using Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), nuclear magnetic resonance (NMR), and thermogravimetric analysis (TGA). The durability of Pickering emulsions was examined at various volume fractions of the oil phase and concentrations of nanoparticles. Compared to the emulsion stabilized by LC-CD, the one stabilized by LC-CD-VE showed superior storage stability. Moreover, for the delivery of BC, Pickering emulsions stabilized by LC-CD and LC-CD-VE can outperform bulk oil and Tween 80 stabilized emulsions in terms of UV light stability, storage stability, and bioaccessibility. This work could offer fresh perspectives on stabilizer alternatives for Pickering emulsion delivery systems.

Peptide Supramolecular Self-Assembly: Regulatory Mechanism, Functional Properties, and Its Application in Foods

Peptide self-assembly, due to its diverse supramolecular nanostructures, excellent biocompatibility, and bright application prospects, has received wide interest from researchers in the fields of biomedicine and green life technology and the food industry. Driven by thermodynamics and regulated by dynamics, peptides spontaneously assemble into supramolecular structures with different functional properties. According to the functional properties derived from peptide self-assembly, applications and development directions in foods can be found and explored. Therefore, in this review, the regulatory mechanism is elucidated from the perspective of self-assembly thermodynamics and dynamics, and the functional properties and application progress of peptide self-assembly in foods are summarized, with a view to more adaptive application scenarios of peptide self-assembly in the food industry.

Protein Nanotubes as Advanced Material Platforms and Delivery Systems

Protein nanotubes (PNTs) as state-of-the-art nanocarriers are promising for various potential applications both in the food and pharmaceutical industries. Derived from edible starting sources like α-lactalbumin, lysozyme, and ovalbumin, PNTs bear properties of biocompatibility and biodegradability. Their large specific surface area and hydrophobic core facilitate chemical modification and loading of bioactive substances, respectively. Moreover, their enhanced permeability and penetration ability across biological barriers such as intestinal mucus, extracellular matrix, and thrombus clot, make it promising platforms for health-related applications. Most importantly, their simple preparation processes enable large-scale production, supporting applications in the biomedical and nanotechnological fields. Understanding the self-assembly principles is crucial for controlling their morphology, size, and shape, and thus provides the ground to a multitude of applications. Here, the current state-of-the-art of PNTs including their building materials, physicochemical properties, and self-assembly mechanisms are comprehensively reviewed. The advantages and limitations, as well as challenges and prospects for their successful applications in biomaterial and pharmaceutical sectors are then discussed and highlighted. Potential cytotoxicity of PNTs and the need of regulations as critical factors for enabling in vivo applications are also highlighted. In the end, a brief summary and future prospects for PNTs as advanced platforms and delivery systems are included.

Rapid UV Photo-Cross-Linking of α-Lactalbumin Hydrogel Biomaterial To Enable Wound Healing

Although both the function and biocompatibility of protein-based biomaterials are better than those of synthetic materials, their usage as medical material is currently limited by their high costs, low yield, and low batch-to-batch reproducibility. In this article, we show how α-lactalbumin (α-LA), rich in tryptophan, was used to produce a novel type of naturally occurring, protein-based biomaterial suitable for wound dressing. To create a photo-cross-linkable polymer, α-LA was methacrylated at a 100-g batch scale with >95% conversion and 90% yield. α-LAMA was further processed using photo-cross-linking-based advanced processing techniques such as microfluidics and 3D printing to create injectable hydrogels, monodispersed microspheres, and patterned scaffolds. The obtained α-LAMA hydrogels show promising biocompatibility and degradability during in vivo testing. Additionally, the α-LAMA hydrogel can accelerate post-traumatic wound healing and promote new tissue regeneration. In conclusion, cheap and safe α-LAMA-based biomaterials could be produced, and they have a beneficial effect on wound healing. As a result, there may arise a potential partnership between the dairy industry and the development of pharmaceuticals.

SVR Chemometrics to Quantify β-Lactoglobulin and α-Lactalbumin in Milk Using MIR

Protein content variation in milk can impact the quality and consistency of dairy products, necessitating access to in-line real time monitoring. Here, we present a chemometric approach for the qualitative and quantitative monitoring of β-lactoglobulin and α-lactalbumin, using mid-infrared spectroscopy (MIR). In this study, we employed Hotelling T2 and Q-residual for outlier detection, automated preprocessing using nippy, conducted wavenumber selection with genetic algorithms, and evaluated four chemometric models, including partial least squares, support vector regression (SVR), ridge, and logistic regression to accurately predict the concentrations of β-lactoglobulin and α-lactalbumin in milk. For the quantitative analysis of these two whey proteins, SVR performed the best to interpret protein concentration from 197 MIR spectra originating from 42 Cornell University samples of preserved pasteurized modified milk. The R2 values obtained for β-lactoglobulin and α-lactalbumin using leave one out cross-validation (LOOCV) are 92.8% and 92.7%, respectively, which is the highest correlation reported to date. Our approach introduced a combination of preprocessing automation, genetic algorithm-based wavenumber selection, and used Optuna to optimize the framework for tuning hyperparameters of the chemometric models, resulting in the best chemometric analysis of MIR data to quantitate β-lactoglobulin and α-lactalbumin to date.

Emulsifying performance of the hexadecyltrimethylammonium bromide (CTAB) complexed alginate microgels: Effects from their deformability on oil-water interface

Hexadecyltrimethylammonium bromide complexed alginate-Ca2+ microgels (C/AMGs) were developed as emulsifiers, which shown remarkably improved emulsifying performance than non-complexed alginate-Ca2+ microgels (AMGs) in previous study. This work focus on the impact of deformability on the emulsifying performance of C/AMGs. By regulating alginate concentration (1.0-4.0 wt%), microgels with different deformability were prepared. Deformability was proved to have great influence on the emulsifying performance of C/AMGs, which was evaluated by Langmuir trough measurements, emulsion appearance, centrifugation stability, digestive behavior, and oxidative stability. Particle size and SEM images indicated microgels prepared with lower alginate concentration are more deformable. C/AMGs (2.0 wt%) exhibits the best emulsifying performance, which could be ascribed to the appreciated deformability and mechanical strength. Digestive behavior and oxidative stability of alginate-Ca2+ microgel (2.0 wt%) stabilized emulsions were further investigated. Compared with alginate-Ca2+ microgel (2.0 wt%) stabilized emulsions, C/AMGs (2.0 wt%) stabilized emulsions shown delayed lipid digestion and lower POV. Results of this work supporting that Mickering mechanism have potential in fabricating functional emulsions based on natural polysaccharides.

Correlationship between self-assembly behavior and emulsion stabilization of pea protein-high methoxyl pectin complexes treated with ultrasound at pH 2.0

This study investigated the effects of ultrasound on the self-assembly behavior of pea protein (PP)-high methoxyl pectin (HMP) complexes at pH 2.0 through transmission electron microscopy (TEM), Fourier transform infrared spectroscopy (FTIR), and intrinsic fluorescence analysis. The emulsion stabilization mechanism of PP-HMP treated with ultrasound (PP-HMP-US) was also elucidated. The results indicated that ultrasound increased the emulsifying activity index (EAI) and emulsifying stability index (ESI) of PP-HMP. Moreover, PP-HMP-US-based emulsions formed small, dispersed oil drops, which were stable during storage. PP-HMP- and PP-HMP-US-based emulsions did not demonstrate any creaming. The TEM results revealed that ultrasound can regulate the self-assembly behavior of PP and HMP to form spherical particles with a core-shell structure. This structure possessed low turbidity, a small particle size, and high absolute zeta potential values. The FTIR and intrinsic fluorescence spectra demonstrated that ultrasound increased the α-helix and β-sheet contents and exposed the tryptophan groups to more hydrophilic environments. Ultrasound also promoted the PP-HMP self-assembly through electrostatic interaction and improved its oil-water interfacial behavior, as indicated by the EAI and ESI values of PP-HMP-US-based emulsions. The current results provide a reference for the development of an innovative emulsifier prepared by ultrasound-treated protein-pectin complexes at low pH.

The colloid and interface strategies to inhibit lipid digestion for designing low-calorie food

Although fat is one of the indispensable components of food flavor, excessive fat consumption could cause obesity, metabolism syndromes and an imbalance in the intestinal flora. In the pursuit of a healthy diet, designing fat reducing foods by inhibiting lipid digestion and calorie intake is a promising strategy. Altering the gastric emptying rates of lipids as well as acting on the lipase by suppressing the enzymatic activity or limiting lipase diffusion via interfacial modulation can effectively decrease lipolysis rates. In this review, we provide a comprehensive overview of colloid-based strategies that can be employed to retard lipid hydrolysis, including pancreatic lipase inhibitors, emulsion-based interfacial modulation and fat substitutes. Plants-/microorganisms-derived lipase inhibitors bind to catalytic active sites and change the enzymatic conformation to inhibit lipase activity. Introducing oil-in-water Pickering emulsions into the food can effectively delay lipolysis via steric hindrance of interfacial particulates. Regulating stability and physical states of emulsions can also affect the rate of hydrolysis by altering the active hydrolysis surface. 3D network structure assembled by fat substitutes with high viscosity can not only slow down the peristole and obstruct the diffusion of lipase to the oil droplets but also impede the transportation of lipolysis products to epithelial cells for adsorption. Their applications in low-calorie bakery, dairy and meat products were also discussed, emphasizing fat intake reduction, structure and flavor retention and potential health benefits. However, further application of these strategies in large-scale food production still requires more optimization on cost and lipid reducing effects. This review provides a comprehensive review on colloidal approaches, design, principles and applications of fat reducing strategies to meet the growing demand for healthier diet and offer practical insights for the low-calorie food industry.

Precursor template-induced egg white-derived peptides self-assembly for the enhancement of curcumin: Structure, environmental stability, and bioavailability

Natural multicomponent peptides with abundant bioactivity, varied sizes, and tunable interaction potential are available for rational designing novel self-assembled delivery carriers. Herein, we exploited zein-hyaluronic acid nanoparticles (Z-HA NPs) with a predetermined ordered structure as precursor templates to induce the self-assembly of egg white-derived peptides (EWDP) to generate stable spherical architectures for the enhancement of curcumin (Cur). The resulting Z-EWDP-HA NPs encapsulated hydrophobic Cur through robust hydrogen bonding and hydrophobic interactions with high encapsulation efficiency (97.38% at pH 7.0). The NPs presented superior Cur aqueous solubility, redispersibility, and photothermal stability. More importantly, the self-assembled EWDP could exert synergistic antioxidant activity with Cur and enhance the bioaccessibility of Cur. Meanwhile, the favorable biocompatibility and membrane affinity of EWDP further prolonged residence and time-controlled release feature of Cur in the small intestine. Precursor template-induced multicomponent peptides' self-assembly provides an efficient and controllable strategy for co-enhanced bioactivity and self-assembly capacity of peptides, which could dramatically broaden the functionalization of multicomponent peptides hydrolyzed from natural food proteins.

Ion-Induced Reassembly between Protein Nanotubes and Nanospheres

Proteins used as building blocks to template nanostructures with manifold morphologies have been widely reported. Understanding their self-assembly and reassembly mechanism is important for designing functional biomaterials. Herein, we show that enzyme-hydrolyzed α-lactalbumin (α-lac) can self-assemble into either nanotubes in the presence of Ca2+ ions or nanospheres in the absence of Ca2+ in solution. Remarkably, such assembled α-lac nanotubes can be elongated by adding preassembled α-lac nanospheres and Ca2+ solution, which suggests that the self-assembled α-lac nanospheres undergo disassembly and reassembly processes into existing nanotube nuclei. By performing atomic force microscopy (AFM), transmission electron microscopy (TEM), and confocal laser scanning microscopy (CLSM), it indicates that there is an equilibrium among nanotubes, nanospheres, hydrolyzed α-lac, and Ca2+ in solution. The structural transition between nanotubes and nanospheres is driven from a less stable structure into a more stable structure determined by the conditions. During the transition from nanospheres into nanotubes, the hydrolyzed α-lac in nanospheres transfers into helical ribbon form at both nanotube extremities. Then helical ribbons close into mature nanotubes, extending the length of the initial nuclei. Besides, by dilution or adding ethylene glycol bis(2-aminoethyl ether) tetraacetic acid (EGTA), the decreased Ca2+ concentration in solution drives the Ca2+ dissociating from nanotubes into solution, leading to the transitions from nanotubes into nanospheres. The reversible transformation between nanotubes and nanospheres is achieved by adjusting the pH value from 7.5 to 5.0 and back to 7.5. This is because the stability of nanotubes decreases from pH 7.5 to 5 but increases from 5 to 7.5. Significantly, this approach can be used for the fabrication of various responsive nanomaterials from the same starting material.

The bioavailability, metabolism and microbial modulation of curcumin-loaded nanodelivery systems

Curcumin (Cur), the major bioactive component of turmeric (Curcuma longa) possesses many health benefits. However, low solubility, stability and bioavailability restricts its applications in food. Recently, nanocarriers such as complex coacervates, nanocapsules, liposomes, nanoparticles, nanomicelles, have been used as novel strategies to solve these problems. In this review, we have focused on the delivery systems responsive to the environmental stimuli such as pH-responsive, enzyme-responsive, targeted-to-specific cells or tissues, mucus-penetrating and mucoadhesive carriers. Besides, the metabolites and their biodistribution of Cur and Cur delivery systems are discussed. Most importantly, the interaction between Cur and their carriers with gut microbiota and their effects of modulating the gut health synergistically were discussed comprehensively. In the end, the biocompatibility of Cur delivery systems and the feasibility of their application in food industry is discussed. This review provided a comprehensive review of Cur nanodelivery systems, the health impacts of Cur nanocarriers and an insight into the application of Cur nanocarriers in food industry.

A Comprehensive Review of Self-Assembled Food Protein-Derived Multicomponent Peptides: From Forming Mechanism and Structural Diversity to Applications

Food protein-derived multicomponent peptides (FPDMPs) are a natural blend of numerous peptides with various bioactivities and multiple active sites that can assume several energetically favorable conformations in solutions. The remarkable structural characteristics and functional attributes of FPDMPs make them promising codelivery carriers that can coassemble with different bioactive ingredients to induce multidimensional structures, such as fibrils, nanotubes, and nanospheres, thereby producing specific health benefits. This review offers a prospective analysis of FPDMPs-based self-assembly nanostructures, focusing on the mechanism of formation of self-assembled FPDMPs, the internal and external stimuli affecting peptide self-assembly, and their potential applications. In particular, we introduce the exciting prospect of constructing functional materials through precursor template-induced self-assembly of FPDMPs, which combine the bioactivity and self-assembly capacity of peptides and could dramatically broaden the functional utility of peptide-based materials.

Investigation and Characterization of Pickering Emulsion Stabilized by Alkali-Treated Zein (AZ)/Sodium Alginate (SA) Composite Particles

Pickering emulsions stabilized by food-grade colloidal particles have attracted increasing attention in recent years due to their "surfactant-free" nature. In this study, the alkali-treated zein (AZ) was prepared via restricted alkali deamidation and then combined with sodium alginate (SA) in different ratios to obtain AZ/SA composite particles (ZS), which were used to stabilize Pickering emulsion. The degree of deamidation (DD) and degree of hydrolysis (DH) of AZ were 12.74% and 6.58% respectively, indicating the deamidation occurred mainly in glutamine on the side chain of the protein. After the treatment with alkali, AZ particle size decreased significantly. Moreover, the particle size of ZS with different ratios was all less than 80 nm. when the AZ/SA ratio was 2:1(Z2S1) and 3:1(Z3S1), the three-phase contact angle (θ_o/w) were close to 90°, which was favorable for stabilizing the Pickering emulsion. Furthermore, at a high oil phase fraction (75%), Z3S1-stabilized Pickering emulsions showed the best long-term storage stability within 60 days. Confocal laser scanning microscope (CLSM) observations showed that the water-oil interface was wrapped by a dense layer of Z3S1 particles with non-agglomeration between independent oil droplets. At constant particle concentration, the apparent viscosity of the Pickering emulsions stabilized by Z3S1 gradually decreased with increasing oil phase fraction, and the oil-droplet size and the Turbiscan stability index (TSI) also gradually decreased, exhibiting solid-like behavior. This study provides new ideas for the fabrication of food-grade Pickering emulsions and will extend the future applications of zein-based Pickering emulsions as bioactive ingredient delivery systems.

The fortification of encapsulated soy isoflavones and texture modification of soy milk by α-lactalbumin nanotubes

Nanocarriers can improve the dispersibility of hydrophobic bioactive compounds and potentially improve the texture of liquid food formulations. Here, nanotubes (NTs) with a high aspect ratio formed by self-assembly of peptides partially hydrolyzed from α-lactalbumin (α-lac) were used to deliver soy isoflavones (IFs) and modify soy milk texture. IFs encapsulated by nanotube (NT/IFs) via hydrophobic interactions, which had improved dispersibility, with a maximum loading efficiency of 4%. The rheological characterization showed that the nanotubes enhanced the viscoelastic property and long term-stability of soy milk. About 80% of the NT/IFs in soy milk survived simulated in in vitro gastric digestion promoting the release of IFs in the intestinal phase. Overall, this work demonstrated that α-lac nanotubes may be a multi-functional carrier system for hydrophobic compounds providing beneficial changes to functional food texture.

Improving the physicochemical stability of Pickering emulsion stabilized by glycosylated whey protein isolate/cyanidin-3-glucoside to deliver curcumin

Protein-polysaccharide-polyphenol delivery systems function as a promising tool to deliver bioactive ingredients aiming to improve their solubility and bioavailability. In this study, whey protein isolate (WPI), short-chain inulin (SCI), and cyanidin-3-glucoside (C3G) were first used to stabilize Pickering emulsions. The physicochemical properties and stability of curcumin encapsulated or not in Pickering emulsions were explored. Results showed that glycosylation and C3G reduced surface and interfacial tension on protein surfaces and inhibited the aggregation of emulsion droplets, thereby reducing the emulsion's particle size. WPI-SCI/C3G stabilized Pickering emulsion had the best stability. The CLSM results showed that the WPI-SCI and WPI-SCI/C3G stabilized emulsions were uniformly dispersed, suggesting that glycosylation and the interaction between protein and C3G enhanced the adsorption capacity of the interfacial protein and improved the stability of the Pickering emulsion. The retention rates of curcumin-loaded WPI-SCI- (67.34 %) and WPI-SCI/C3G- (77.07 %) stabilized Pickering emulsions on day 8 of storage were higher than those in WPI- (33.97 %) and WPI/C3G- (37.02 %) stabilized emulsions, and the degradation half-life was also extended from 7 days to >15 days. These findings provide a theoretical basis for the application of WPI Pickering emulsion and indicate a useful means for the delivery of bioactive components.

Preparation of a multifunctional non-stick tamarind polysaccharide-polyvinyl alcohol hydrogel immobilized with a quorum quenching enzyme for maintaining fish freshness

Hydrogels have become promising materials for food packaging due to their unique microstructure. However, hydrogel materials suitable for seafood preservation have rarely been reported. In this study, a tamarind polysaccharide-polyvinyl alcohol hydrogel with the ability to maintain seafood freshness was prepared and characterized. The hydrogel possesses quick self-healing, good tissue fitting, and freezing tolerance capability. Moreover, a peeling force of only 0.1 N between the hydrogel and the fillet tissue confirmed the non-stick properties. The FTIR characteristic peak at 1600 cm^-1 and 1450 cm^-1 proved the ester bond-based chemical cross-linking of the hydrogel. Release profiles at pH 6.0 to 8.0 verified the pH-responsive release of quorum-quenching (QQ) enzymes over 120 h, which enabled the hydrogel to achieve biofilm and protease inhibitory activities. In vivo spoilage tests showed that the shelf life of hydrogel-coated red snapper fillets was extended by >3 days. These results illustrate the potential of the prepared hydrogel as functional packaging for seafood preservation.

Platelet Membrane Cloaked Nanotubes to Accelerate Thrombolysis by Thrombus Clot-Targeting and Penetration

Thrombotic diseases have a high rate of mortality and disability, and pose a serious threat to global public health. Currently, most thrombolytic drugs especially protein drugs have a short blood-circulation time, resulting in low thrombolytic efficiency. Therefore, a platelet membrane (Pm) cloaked nanotube (NT-RGD/Pm) biomimetic delivery system with enhanced thrombolytic efficiency is designed. Nanotubes (NT) with an excellent clot-penetration properties are used to load a protein thrombolytic drug urokinase (Uk). Platelet-targeting arginine glycine-aspartic peptide (RGD) is grafted onto the surface of the nanotubes (NT-RGD) prior to cloaking. Multiple particle tracking (MPT) technique and confocal laser scanning microscope (CLSM) analysis are applied and the results show that the nanotubes possess a strong penetration and diffusion capacity in thrombus clots. After the Pm cloaking on NT-RGD/Uk, it shows a thrombus microenvironmental responsive release property and the half-life of Uk is six times longer than that of free Uk. Most importantly, NT-RGD-Uk/Pm exhibits a 60% thrombolytic efficiency in the FeCl₃ -induced thrombosis mouse model, and it is able to significantly reduce the bleeding side effects of Uk. This Pm-cloaked nanotube system is an effective and promising platform for the controlled and targeted delivery of drugs for the thrombus treatment.

Progress in the Application of Food-Grade Emulsions

The detailed investigation of food-grade emulsions, which possess considerable structural and functional advantages, remains ongoing to enhance our understanding of these dispersion systems and to expand their application scope. This work reviews the applications of food-grade emulsions on the dispersed phase, interface structure, and macroscopic scales; further, it discusses the corresponding factors of influence, the selection and design of food dispersion systems, and the expansion of their application scope. Specifically, applications on the dispersed-phase scale mainly include delivery by soft matter carriers and auxiliary extraction/separation, while applications on the scale of the interface structure involve biphasic systems for enzymatic catalysis and systems that can influence substance digestion/absorption, washing, and disinfection. Future research on these scales should therefore focus on surface-active substances, real interface structure compositions, and the design of interface layers with antioxidant properties. By contrast, applications on the macroscopic scale mainly include the design of soft materials for structured food, in addition to various material applications and other emerging uses. In this case, future research should focus on the interactions between emulsion systems and food ingredients, the effects of food process engineering, safety, nutrition, and metabolism. Considering the ongoing research in this field, we believe that this review will be useful for researchers aiming to explore the applications of food-grade emulsions.

Formation, Structure and stability of high internal phase Pickering emulsions stabilized by BSPI-C3G covalent complexes

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The HIIPPE was stabilized by BSPI-C3G covalent particles.

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HIPPEs stabilized with 74% (v/v) oil phase fraction have a stable gel-like state.

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HIPPEs stability was the best with the 3 % (w/v) BSPI-C3G particle concentration.

Food-grade high internal phase Pickering emulsions (HIPPEs) are stabilized by protein-based particles, which have attracted extensive attention due to their good gel-like structure. The black soybean isolate protein/cyanidin-3-O-glucoside (BSPI-C3G) covalent particles were used as a particulate emulsifier to form stable HIPPEs with oil phase fractions (74 % v/v) and low particle concentrations (0.5 %–3 % w/v) The particle size distribution and microstructure demonstrated that the BSPI-C3G covalent particles acted as an interfacial layer and surrounded the oil droplets. As the concentration of BSPI-C3G particles increased from 0.5 % to 3 %, the droplet size, elasticity, antioxidant capacity of the heated or stored HIPPEs more stable. So, the HIPPEs had the best stability with the BSPI-C3G particle at 3 % (w/v) concentration. These findings may extend the application of BSPI and C3G in foods and provide the guidelines for the rational design of food-grade HIPPEs stabilized by protein/anthocyanin complexes.

Intestinal-targeted nanotubes-in-microgels composite carriers for capsaicin delivery and their effect for alleviation of Salmonella induced enteritis

Salmonella is a word-wide food-borne pathogen, which can cause severe enteritis and intestinal microbiota imbalance. Capsaicin (Cap), a food-based bioactive ingredient, has antibacterial and anti-inflammatory properties. However, its low solubility, low bioavailability and the irritation to digestive tract greatly limit its applications. Here, an intestinal responsively "nanotubes-in-microgel" composite carrier was constructed by capturing α-lactalbumin (α-lac) nanotubes in low-methoxy pectin microgels (LMP-NT) (52 μm). Cap was loaded in such system via hydrophobic interaction with a loading capacity of 38.02 mg/g. The LMP microgels remained stable and protected NT/Cap from early releasing in the gastric condition. It showed an excellent mucoadhesive capacity, which can prolong the intestinal retention up to 12 h and control release NT/Cap in intestine. Afterward, NT/Cap could penetrate across the mucus layer deeply and enter the intestinal villi epithelial cells efficiently. LMP-NT microgels achieved a mucoadhesive-to-penetrating transition in response to intestinal pH, improving the epithelium absorption and the in vivo bioavailability of Cap. Oral administration of LMP-NT/Cap could effectively alleviate enteritis caused by Salmonella infection and maintain the homeostasis of gut microbiota. Overall, this work suggested that LMP-NT composite microgels were promising for intestine-targeted and oral delivery of hydrophobic bioactive food compounds.

Squalene-Rich Amaranth Oil Pickering Emulsions Stabilized by Native α-Lactalbumin Nanoparticles

The stabilization of Pickering emulsions by nanoparticles has drawn great interest in the field of food science and technology. In this study, α-Lactalbumin nanoparticles prepared by the desolvation and cross-linking method from protein solutions with initial pH values of 9 and 11 were used to stabilize squalene-rich amaranth oil Pickering o/w emulsions. The effect of different concentrations of nanoparticles on the size, size distribution, ζ potential, and emulsion stability was evaluated using dynamic light scattering, electron microscopy, and light backscattering. Dependence of the emulsions' droplet size on the nanoparticle concentration was observed, and the critical coverage ratio was reached when 5-10% nanoparticles concentration was used. Our findings suggest that α-LA nanoparticles at a 10% concentration can be used as novel stabilizers for Pickering emulsions to provide protection for beneficial lipophilic bioactive compounds. This is the first time that native α-LA nanoparticles have been used as stabilizers of Pickering emulsions.

Bioactives in bovine milk: chemistry, technology, and applications

The significance of dairy in human health and nutrition is gaining significant momentum as consumers continue to desire wholesome, nutritious foods to fulfill their health and wellness needs. Bovine milk not only consists of all the essential nutrients required for growth and development, it also provides a broad range of bioactive components that play an important role in managing human homeostasis and immune function. In recent years, milk bioactives, including α-lactalbumin, lactoferrin, glycomacropeptide, milk fat globule membrane, and milk oligosaccharides, have been intensively studied because of their unique bioactivity and functionality. Challenges for the application of these bioactive components in food and pharmaceutical formulations are associated with their isolation and purification on an industrial scale and also with their physical and chemical instability during processing, storage, and digestion. These challenges can be overcome by advanced separation techniques and sophisticated nano- or micro-encapsulation technologies. Current knowledge about the chemistry, separation, and encapsulation technology of major bioactives derived from bovine milk and their application in the food industry is reviewed here.