pH switchable Pickering emulsion based on soy peptides functionalized calcium phosphate particles

Pickering emulsion co-delivery system: Stimuli-responsive biomineralized particles act as particulate emulsifiers and bioactive carriers

Pickering emulsions provide a promising platform for the efficient delivery of bioactive. However, co-delivery of fragile bioactives with different physicochemical properties for comprehensive effects still faces practical challenges due to the limited protection for bioactives and the lack of stimuli-responsive property for on-demand release. Herein, a stimuli-responsive co-delivery system is developed based on biomineralized particles stabilized Pickering emulsions. In this tailor co-delivery system, hydrophilic bioactive (pepsin) with the fragile structure is encapsulated and immobilized by biomineralization, the obtained biomineralized particles (PPS@CaCO3) are further utilized as emulsifiers to form O/W Pickering emulsions, in which the hydrophobic oxidizable bioactive (curcumin) is stably trapped into the dispersed phase. The results show that two bioactives are successfully co-encapsulated in Pickering emulsions, and benefiting from the protection capacities of biomineralization and Pickering emulsions, the activity of pepsin and curcumin shows a 7.33-fold and 144.83-fold enhancement compared to the free state, respectively. Moreover, In vitro study demonstrates that Pickering emulsions enable to co-release of two bioactives with high activity retention by the acid-induced hydrolyzation of biomineralized particles. This work provides a powerful stimuli-responsive platform for the co-delivery of multiple bioactive compounds, enabling high activity of bioactives for the comprehensive health effects.

Condensation of Soy Protein Peptides Contributes to Sequester Bile Acids and Mitigate LPS-Induced Inflammation

Soy protein is widely known to have serum triglyceride (TG) and cholesterol-lowering effects associated with a reduced risk of cardiovascular disease. Recent studies highlighted that the extension region (ER) domain of soy 7S globulin (β-conglycinin) is a key component responsible for the serum TG-lowering effect via modulation of bile acid (BA) homeostasis. Here, we studied the sequestration of BAs by ER peptides during intestinal digestion in vitro and assessed the anti-inflammatory effects of ER peptides using Caco-2/HT29-MTX/RAW264.7 triple-cell cocultures as an intestine cell model. Results show that ER peptides, which share characteristics of intrinsically disordered regions (IDRs), are capable of forming peptide condensates and exhibit the capability to sequester BA-containing colloidal structures during intestinal digestion in vitro. Moreover, BAs enhance the penetration of peptide condensates within the mucus layer, enabling ER peptides to mitigate lipopolysaccharide (LPS)-induced gut inflammation. These results provide a possible explanation for the molecular mechanisms underlying the modulation of BA homeostasis by soybean proteins.

Computational Insights into a CO2-Responsive Emulsion Prepared Using the Superamphiphile Assembled by Electrostatic Interactions

The superamphiphiles exhibit broad prospects for fabricating stimuli-responsive emulsions. Because the superamphiphiles are assembled via noncovalent interactions, they have the advantage of fast response and high efficiency. Recently, a series of switchable emulsions using CO2-responsive superamphiphiles have been developed, which extends the applications of CO2-responsive materials in widespread field. However, there is still a lack of fundamental understanding on the switching mechanism related to the assembled structure of superamphiphiles at the oil-water interface. We employed molecular dynamics (MD) simulations to investigate the reversible emulsification/demulsification process of a responsive emulsion system stabilized by a recently developed responsive superamphiphile (BTOA), which consists of oleic acid (OA) and cationic amine (named 1,3-bis(aminopropyl)tetramethyldisiloxane, BT). The simulation results present the morphologies in both the emulsion and demulsification states. It is found that the ionized OA- and the protonated BT+ together form an adsorption layer at the oil-water interface. The hydrophobic parts of BT+ are inserted into the adsorption layer, and the two amine groups contact the water phase. This adsorption layer reduces the interfacial tension and stabilizes the emulsion. After the bubbling of CO2, the surfactants were fully protonated to OA and BT2+. Because of the changes in the molecular polarity, OA and BT2+ entered the oil and water phases, respectively, resulting in demulsification. The structural and dynamical properties were analyzed to reveal the different intermolecular interactions that were responsible for the reversible reversibility of the emulsion. The observations are considered to be complementary to experimental studies and are expected to provide deeper insights into studies on developing responsive materials via supramolecular assemblies.

Food-Grade Oil-in-Water (O/W) Pickering Emulsions Stabilized by Agri-Food Byproduct Particles

In recent years, emulsions stabilized by solid particles (known as Pickering emulsions) have gained considerable attention due to their excellent stability and for being environmentally friendly compared to the emulsions stabilized by synthetic surfactants. In this context, edible Pickering stabilizers from agri-food byproducts have attracted much interest because of their noteworthy benefits, such as easy preparation, excellent biocompatibility, and unique interfacial properties. Consequently, different food-grade particles have been reported in recent publications with distinct raw materials and preparation methods. Moreover, emulsions stabilized by solid particles can be applied in a wide range of industrial fields, such as food, biomedicine, cosmetics, and fine chemical synthesis. Therefore, this review aims to provide a comprehensive overview of Pickering emulsions stabilized by a diverse range of edible solid particles, specifically agri-food byproducts, including legumes, oil seeds, and fruit byproducts. Moreover, this review summarizes some aspects related to the factors that influence the stabilization and physicochemical properties of Pickering emulsions. In addition, the current research trends in applications of edible Pickering emulsions are documented. Consequently, this review will detail the latest progress and new trends in the field of edible Pickering emulsions for readers.

Recent progress in fish oil-based emulsions by various food-grade stabilizers: Fabrication strategy, interfacial stability mechanism and potential application

Fish oil, rich in a variety of long-chain ω-3 PUFAs, is widely used in fortified foods due to its broad-spectrum health benefits. However, its undesired characteristics include oxidation sensitivity, poor water solubility, and fishy off-flavor greatly hinder its exploitation in food field. Over the past two decades, constructing fish oil emulsions to encapsulate ω-3 PUFAs for improving their physicochemical and functional properties has undergone great progress. This review mainly focuses on understanding the fabrication strategies, stabilization mechanism, and potential applications of fish oil emulsions, including fish oil microemulsions, nanoemulsions, double emulsions, Pickering emulsions and emulsion gels. Furthermore, the role of oil-water interfacial stabilizers in the fish oil emulsions stability will be discussed with a highlight on food-grade single emulsifiers and natural complex systems for achieving this purpose. Additionally, its roles and applications in food industry and nutrition field are delineated. Finally, possible innovative food trends and applications are highlighted, such as novel fish oil-based delivery systems construction (e.g., Janus emulsions and nutraceutical co-delivery systems), exploring digestion and absorption mechanisms and enhancing functional evaluation (e.g., nutritional supplement enhancer, and novel fortified/functional foods). This review provides a reference for the application of fish oil-based emulsion systems in future precision diet intervention implementations.

The Potential Application of Pickering Multiple Emulsions in Food

Emulsions stabilized by adsorbed particles—Pickering particles (PPs) instead of surfactants and emulsifiers are called Pickering emulsions. Here, we review the possible uses of Pickering multiple emulsions (PMEs) in the food industry. Food-grade PMEs are very complex systems with high potential for application in food technology. They can be prepared by traditional two-step emulsification processes but also using complex techniques, e.g., microfluidic devices. Compared to those stabilized with an emulsifier, PMEs provide more benefits such as lower susceptibility to coalescence, possible encapsulation of functional compounds in PMEs or even PPs with controlled release, etc. Additionally, the PPs can be made from food-grade by-products. Naturally, w/o/w emulsions in the Pickering form can also provide benefits such as fat reduction by partial replacement of fat phase with internal water phase and encapsulation of sensitive compounds in the internal water phase. A possible advanced type of PMEs may be stabilized by Janus particles, which can change their physicochemical properties and control properties of the whole emulsion systems. These emulsions have big potential as biosensors. In this paper, recent advances in the application of PPs in food emulsions are highlighted with emphasis on the potential application in food-grade PMEs.

Redox and pH-responsive emulsions based on TiO2 nanoparticles and ferrocene derivates

We synthesized a novel surfactant ferrocene azine (FcA) and developed a redox and pH-responsive emulsion stabilized by TiO2 nanoparticles and oxidized ferrocene azine (Fc+A) with fluorescence through simple mixing instead...

Edible mayonnaise-like Pickering emulsion stabilized by pea protein isolate microgels: Effect of food ingredients in commercial mayonnaise recipe

Particle stabilized O/W Pickering emulsion has great potential for making egg-free mayonnaise. In this study, we fabricated pea protein isolate (PPI) microgels by gel-breaking method and applied in mayonnaise-like Pickering emulsion. The effects of acetic acid (pH), sodium chloride (NaCl), and sucrose, which are typically used in commercial mayonnaise were studied. The minimum droplet size (47.0 μm) was found below isoelectric point. The NaCl decreased ζ-potential to almost 0 and risen droplet size to 75.9 μm. The sucrose enhanced the emulsion's viscosity while lowering thixotropic recovery rate. Based on droplet size, viscosity, thixotropic recovery, and microstructure; 350 mmol NaCl and 4 wt% sucrose was finally used to make egg-free mayonnaise-like Pickering emulsion, and showed similar properties compared with commercial mayonnaise, and the thixotropy recovery rate was near 100%. A plant-scale test further confirmed the feasibility. The results showed the PPI microgels had a strong application prospect to form egg-free mayonnaise.

Fabrication of Bacterial Cellulose Nanofibers/Soy Protein Isolate Colloidal Particles for the Stabilization of High Internal Phase Pickering Emulsions by Anti-solvent Precipitation and Their Application in the Delivery of Curcumin

In this study, the anti-solvent precipitation and a simple complex method were applied for the preparation of bacterial cellulose nanofiber/soy protein isolate (BCNs/SPI) colloidal particles. Fourier transform IR (FT-IR) showed that hydrogen bonds generated in BCNs/SPI colloidal particles via the anti-solvent precipitation were stronger than those generated in BCNs/SPI colloidal particles self-assembled by a simple complex method. Meanwhile, the crystallinity, thermal stability, and contact angle of BCNs/SPI colloidal particles via the anti-solvent precipitation show an improvement in comparison with those of BCNs/SPI colloidal particles via a simple complex method. BCNs/SPI colloidal particles via the anti-solvent precipitation showed enhanced gel viscoelasticity, which was confirmed by dynamic oscillatory measurements. Furthermore, high internal phase Pickering emulsions (HIPEs) were additionally stable due to their stabilization by BCNs/SPI colloidal particles via the anti-solvent precipitation. Since then, HIPEs stabilized by BCNs/SPI colloidal particles via the anti-solvent precipitation were used for the delivery of curcumin. The curcumin-loaded HIPEs showed a good encapsulation efficiency and high 2,2-diphenyl-1-picrylhydrazyl (DPPH) removal efficiency. Additionally, the bioaccessibility of curcumin was significantly increased to 30.54% after the encapsulation using the prepared HIPEs. Therefore, it can be concluded that the anti-solvent precipitation is an effective way to assemble the polysaccharide/protein complex particles for the stabilization of HIPEs, and the prepared stable HIPEs showed a potential application in the delivery of curcumin.

Edible CaCO3 nanoparticles stabilized Pickering emulsion as calcium-fortified formulation

Background

Nanoparticles assembled from food-grade calcium carbonate have attracted attention because of their biocompatibility, digestibility, particle and surface features (such as size, surface area, and partial wettability), and stimuli-responsiveness offered by their acid-labile nature.

Results

Herein, a type of edible oil-in-water Pickering emulsion was structured by calcium carbonate nanoparticles (CaCO₃ NPs; mean particle size: 80 nm) and medium-chain triglyceride (MCT) for delivery of lipophilic drugs and simultaneous oral supplementation of calcium. The microstructure of the as-made CaCO₃ NPs stabilized Pickering emulsion can be controlled by varying the particle concentration (c) and oil volume fraction (φ). The emulsification stabilizing capability of the CaCO₃ NPs also favored the formation of high internal phase emulsion at a high φ of 0.7–0.8 with excellent emulsion stability at room temperature and at 4 °C, thus protecting the encapsulated lipophilic bioactive, vitamin D3 (VD3), against degradation. Interestingly, the structured CaCO₃ NP-based Pickering emulsion displayed acid-trigged demulsification because of the disintegration of the CaCO₃ NPs into Ca²⁺ in a simulated gastric environment, followed by efficient lipolysis of the lipid in simulated intestinal fluid. With the encapsulation and delivery of the emulsion, VD3 exhibited satisfying bioavailability after simulated gastrointestinal digestion.

Conclusions

Taken together, the rationally designed CaCO₃ NP emulsion system holds potential as a calcium-fortified formulation for food, pharmaceutical and biomedical applications.

Characterization and enhanced functionality of nanoparticles based on linseed protein and linseed gum biocomplexes

The formation, characterization, and functionality of hybrid nanoparticles based on linseed bio-macromolecules extracted as linseed protein (LP) and linseed gum (LG) from the remaining meal after oil extraction were investigated. The assembly of bioparticles at different protein to polysaccharide ratios as a function of pH was characterized in terms of absorbance measurements, dynamic light scattering and surface charge. The wettability of the assembled particles as well as the plain LP and LG was also determined. By increasing the LG proportion in the bioparticles, both the size of the particles and their contact angle tended to decrease, whereas their zeta potential became more negative over the whole studied pH range. The formed negatively charged particles at pH 3 with a 50:50 LP to LG ratio and a size of approximately 300 nm were selected and their functional properties (solubility, emulsifying and foaming properties) were compared to the individual biopolymers. The interaction between LG and LP was found to modify the functional properties of native LP especially at and around its isoelectric point. The LP-LG particles could be useful for stabilizing plant-based emulsions and foams.

Functionalized calcium orthophosphates (CaPO4) and their biomedical applications

Due to the chemical similarity to natural calcified tissues (bones and teeth) of mammals, calcium orthophosphates (abbreviated as CaPO₄) appear to be good biomaterials for creation of artificial bone grafts. However, CaPO₄ alone have some restrictions, which limit their biomedical applications. Various ways have been developed to improve the properties of CaPO₄ and their functionalization is one of them. Namely, since surfaces always form the interfaces between implanted grafts and surrounding tissues, the state of CaPO₄ surfaces plays a crucial role in the survival of bone grafts. Although the biomedically relevant CaPO₄ possess the required biocompatible properties, some of their properties could be better. For example, functionalization of CaPO₄ to enhance cell attachment and cell material interactions has been developed. In addition, to prepare stable formulations from nanodimensional CaPO₄ particles and prevent them from agglomerating, the surfaces of CaPO₄ particles are often functionalized by sorption of special chemicals. Furthermore, there are functionalizations in which CaPO₄ are exposed to various types of physical treatments. This review summarizes the available knowledge on CaPO₄ functionalizations and their biomedical applications.

Modulation of Gut Microbiota by Soybean 7S Globulin Peptide That Involved Lipopolysaccharide-Peptide Interaction

Soybean protein exhibits nutritional significance for the control of metabolic syndrome, and evidence suggests that gut microbiota are implicated in the control of metabolic disorders. This study aimed to investigate the modulation of pepsin-released peptides of soybean 7S globulin on gut microbiota and possible association between changes of gut microbiota composition and lipopolysaccharide (LPS)-peptide interaction. In vitro fermentation experiments showed that the extension region (ER) fragments of soybean 7S globulin selectively suppressed proinflammatory Gram-negative bacteria. ER peptides also promoted the highest production of short-chain fatty acids (SCFAs), which were associated with increase of the relative abundance of Lachnospiraceae and Lactobacillaceae. Isothermal titration calorimetry (ITC) and Langmuir monolayer studies demonstrated that ER peptides exhibited high affinity to LPS in the presence of Ca²⁺ and developed into β-sheet-rich aggregate structures, thus weakening the stability of LPS monolayers. This finding supplies a possible explanation for improvement of the effects of soybean 7S globulin on metabolic disease.

Interaction of Soybean 7S Globulin Peptide with Cell Membrane Model via Isothermal Titration Calorimetry, Quartz Crystal Microbalance with Dissipation, and Langmuir Monolayer Study

To understand the underlying molecular mechanism of the cholesterol-lowering effect of soybean 7S globulins, the interactions of their pepsin-released peptides (7S-peptides) with cell membrane models consisting of dipalmitoylphosphatidylcholine (DPPC), dioleoylphosphatidylcholine (DOPC), and cholesterol (CHOL) were systematically studied. The results showed that 7S-peptides were bound to DPPC/DOPC/CHOL liposomes mainly through van der Waals forces and hydrogen bonds, and the presence of higher CHOL concentrations enhanced the binding affinity (e.g., DPPC/DOPC/CHOL = 1:1:0, binding ratio = 0.114; DPPC/DOPC/CHOL = 1:1:1, binding ratio = 2.02). Compression isotherms indicated that the incorporation of 7S-peptides increased the DPPC/DOPC/CHOL monolayer fluidity and the lipid raft size. The presence of CHOL accelerated the 7S-peptide accumulation on lipid rafts, which could serve as platforms for peptides to develop into β-sheet rich structures. These results allow us to hypothesize that 7S-peptides may indirectly influence membrane protein functions via altering the membrane organization in the enterocytes.

One-step formation of a double Pickering emulsion via modulation of the oil phase composition

A facile one-step emulsification strategy was developed to generate a food-grade W/O/W double Pickering emulsion by using corn-peptide-functionalized calcium phosphate particles (CP-CaP) as emulsifier.