Interfacial engineering of Pickering emulsions stabilized by pea protein-alginate microgels for encapsulation of hydrophobic bioactives.

This study aims to investigate the effects of interfacial layer composition and structure on the formation, physicochemical properties and stability of Pickering emulsions. Interfacial layers were formed using pea protein isolate (PPI), PPI microgel particles (PPIMP), a mixture of PPIMP and sodium alginate (PPIMP-SA), or PPIMP-SA conjugate. The encapsulation and protective effects on different hydrophobic bioactives were then evaluated within these Pickering emulsions. The results demonstrated that the PPIMP-SA conjugate formed thick and robust interfacial layers around the oil droplet surfaces, which increased the resistance of the emulsion to coalescence, creaming, and environmental stresses, including heating, light exposure, and freezing-thawing cycle. Additionally, the emulsion stabilized by the PPIMP-SA conjugate significantly improved the photothermal stability of hydrophobic bioactives, retaining a higher percentage of their original content compared to those in non-encapsulated forms. Overall, the novel protein microgels and the conjugate developed in this study have great potential for improving the physicochemical stability of emulsified foods.

Advances in enhancing the mechanical properties of biopolymer hydrogels via multi-strategic approaches.

The limited mechanical properties of biopolymer-based hydrogels have hindered their widespread applications in biomedicine and tissue engineering. In recent years, researchers have shown significant interest in developing novel approaches to enhance the mechanical performance of hydrogels. This review focuses on key strategies for enhancing mechanical properties of hydrogels, including dual-crosslinking, double networks, and nanocomposite hydrogels, with a comprehensive analysis of their underlying mechanisms, benefits, and limitations. It also introduces the classic application scenarios of biopolymer-based hydrogels and the direction of future research efforts, including wound dressings and tissue engineering based on 3D bioprinting. This review is expected to deepen the understanding of the structure-mechanical performance-function relationship of hydrogels and guide the further study of their biomedical applications.

High internal phase double emulsions stabilized by modified pea protein-alginate complexes: Application for co-encapsulation of riboflavin and ß-carotene.

The application of many hydrophilic and hydrophobic nutraceuticals is limited by their poor solubility, chemical stability, and/or bioaccessibility. In this study, a novel Pickering high internal phase double emulsion co-stabilized by modified pea protein isolate (PPI) and sodium alginate (SA) was developed for the co-encapsulation of model hydrophilic (riboflavin) and hydrophobic (ß-carotene) nutraceuticals. Initially, the effect of emulsifier type in the external water phase on emulsion formation and stability was examined, including commercial PPI (C-PPI), C-PPI-SA complex, homogenized and ultrasonicated PPI (HU-PPI), and HU-PPI-SA complex. The encapsulation and protective effects of these double emulsions on hydrophilic riboflavin and hydrophobic ß-carotene were then evaluated. The results demonstrated that the thermal and storage stabilities of the double emulsion formulated from HU-PPI-SA were high, which was attributed to the formation of a thick biopolymer coating around the oil droplets, as well as thickening of the aqueous phase. Encapsulation significantly improved the photostability of the two nutraceuticals. The double emulsion formulated from HU-PPI-SA significantly improved the in vitro bioaccessibility of ß-carotene, which was mainly attributed to inhibition of its chemical degradation under simulated acidic gastric conditions. The novel delivery system may therefore be used for the development of functional foods containing multiple nutraceuticals.

Effectiveness of probiotic- and fish oil-loaded water-in-oil-in-water (W1/O/W2) emulsions at alleviating ulcerative colitis.

Ulcerative colitis (UC) is a common chronic inflammatory disease that causes serious harm to human health. Probiotics have the effect of improving UC. This study evaluated the preventative potential of water-in-oil-in-water (W1/O/W2) emulsions containing both probiotics and fish oil on UC and associated anxiety-like behavior using a mice model. UC model was established in mice by administering dextran sulfate sodium salt (DSS). Free probiotics, probiotic-loaded emulsions, or fish oil and probiotic co-loaded emulsions were then orally administered to the mice. Various bioassays, histological studies, 16s rDNA gene sequencing, and behavioral experiments were conducted to assess changes in the intestinal environment, microbiota, and anxiety-like behavior of the mice. The fish oil and probiotic co-loaded emulsions significantly reduced the inflammatory response by enhancing tight junction protein secretion (ZO-1, Occludin, and Claudin-1), inhibiting pro-inflammatory factors (TNF-α, and IL-1ß), and promoting short-chain fatty acids (SCFAs) production. These emulsions also modified the gut microbiota by promoting beneficial bacteria and suppressing pathogenic bacteria, thereby restoring a balanced gut microbiota. Notably, the emulsions containing both probiotics and fish oil also ameliorated anxiety-like behavior in the mice. The co-delivery of probiotics and fish oil using W1/O/W2 emulsions has shown significant promise in relieving UC and its associated anxiety-like behavior. These findings provide novel insights into the development of advanced therapeutic strategies for treating UC.

Effect of Traditional Chinese Medicine Characteristic Nursing on Perioperative Nursing of Children with Trichiasis Correction Under General Anesthesia.

Objective: To study the nursing impact of traditional Chinese medicine on children undergoing trichiasis correction surgery with general anesthesia. Methods: A total of 104 children with trichiasis admitted to the hospital for correction under general anesthesia from February 2020 to July 2023 were selected as the research objects. They were randomly divided into a comparison group (52 cases) and an observation group (52 cases). The comparison group was given routine nursing after surgery, and the observation group was given special nursing after surgery. Hamilton Anxiety Scale (HAMA) scores and Wong-Baker Smiley face scale scores of the two groups of children before and after nursing were observed, and the nursing satisfaction of family members of the two groups was evaluated. Results: The anesthesia waking time, operation time, eating time and drinking time of the two groups in the observation group were lower than those in the comparison group, and the differences were statistically significant (P < .05). After nursing, the HAMA and HAMD scores of the two groups decreased, and the HAMA and HAMD scores of the two groups in the observation group were lower than those in the comparison group (P < .05). After nursing, the pain scores of the two groups were decreased, and the pain scores of the observation group were lower than those of the control group (P < .05). The visual acuity of the observation group was significantly better than that of the comparison group, and the difference was statistically significant (P < .05). The total satisfaction rate of the observation group was 94.23%, and that of the comparison group was 80.77%, and the total satisfaction rate of the observation group was higher than that of the comparison group (P < .05). The compliance of the observation group was 96.15%, and that of the comparison group was 84.62%, and the compliance of the observation group was higher than that of the comparison group (P < .05). Within 24h after the operation, the incidence of hunger, thirst, abdominal distension, fever, and irritable crying in the observation group was significantly lower than in the control group, and the difference was statistically significant (P < .05). Conclusion: The application of traditional Chinese medicine-based nursing interventions can effectively alleviate negative emotions, alleviate pain, and enhance the satisfaction of family members towards nursing care for children undergoing trichiasis correction surgery under general anesthesia.

Enhanced functional properties of pea protein isolate microgel particles modified with sodium alginate: Mixtures and conjugates.

Protein microgels are emerging as versatile soft particles due to their desirable interfacial activities and functional properties. In this study, pea protein isolate microgel particles (PPIMP) were prepared by heat treatment and transglutaminase crosslinking, and PPIMP were non-covalently and covalently modified with sodium alginate (SA). The effects of polymer ratio and pH on the formation of PPIMP-SA mixtures and conjugates were investigated. The optimal ratio of PPIMP and SA was found to be 20:1, with the optimal pH being 7 and 10, respectively. PPIMP-SA conjugates were prepared by Maillard reaction. It was found that ultrasound (195 W, 40 min) enhanced the degree of glycation of PPIMP, with a highest value of 37.21 ± 0.71 %. SDS-PAGE, browning intensity and FTIR data also confirmed the formation of PPIMP-SA conjugates. Compared with PPIMP and PPIMP-SA mixtures, PPIMP-SA conjugates exhibited better thermal stability, antioxidant, emulsifying and foaming properties, which opens up opportunities for protein microgel in various food applications.

Zein-based nano-delivery systems for encapsulation and protection of hydrophobic bioactives: A review.

Zein is a kind of excellent carrier materials to construct nano-sized delivery systems for hydrophobic bioactives, owing to its unique interfacial behavior, such as self-assembly and packing into nanoparticles. In this article, the chemical basis and preparation methods of zein nanoparticles are firstly reviewed, including chemical crosslinking, emulsification/solvent evaporation, antisolvent, pH-driven method, etc., as well as the pros and cons of different preparation methods. Various strategies to improve their physicochemical properties are then summarized. Lastly, the encapsulation and protection effects of zein-based nano-sized delivery systems (e.g., nanoparticles, nanofibers, nanomicelles and nanogels) are discussed, using curcumin as a model bioactive ingredient. This review will provide guidance for the in-depth development of hydrophobic bioactives formulations and improve the application value of zein in the food industry.

Encapsulation of multiple probiotics, synbiotics, or nutrabiotics for improved health effects: A review.

Adequate intake of live probiotics can provide benefits to human health and wellbeing. However, free probiotics tend to lose their viability during the production, storage, and distribution of foods, as well as during their passage through the human gastrointestinal tract. A well-designed probiotic encapsulation system can enhance the viability of probiotics in foods and within the gastrointestinal tract, thereby ensuring more live bacteria reach the colon in an active form. This review summarizes the design of encapsulated probiotics and focuses on recent progress on the development of co-encapsulation systems containing mixed probiotics, mixtures of probiotics and prebiotics ("synbiotics"), or mixtures of probiotics and nutraceuticals ("nutrabiotics"). It then discusses the application of these co-encapsulation systems in functional foods, and highlights their potential benefits for human health, including regulating intestinal flora balance, safeguarding intestinal barrier integrity, maintaining immune homeostasis, and regulating blood glucose levels. Finally, challenges facing the large-scale commercialization of probiotic-loaded functional foods are discussed and suggestions for improving their performance are highlighted.

Ultrasound-assisted preparation of lactoferrin-EGCG conjugates and their application in forming and stabilizing algae oil emulsions.

The aim of this study was to prepare lactoferrin-epigallocatechin-3-gallate (LF-EGCG) conjugates and to determine their ability to protect emulsified algal oil against aggregation and oxidation. LF-EGCG conjugates were formed using an ultrasound-assisted alkaline treatment. The ultrasonic treatment significantly improved the grafting efficiency of LF and EGCG and shortened the reaction time from 24 h to 40 min. Fourier transform infrared spectroscopy and circular dichroism spectroscopy analyses showed that the covalent/non-covalent complexes could be formed between LF and EGCG, with the CO and CN groups playing an important role. The formation of the conjugates reduced the α-helix content and increased the random coil content of the LF. Moreover, the antioxidant activity of LF was significantly enhanced after conjugation with EGCG. LF-EGCG conjugates as emulsifiers were better at inhibiting oil droplet aggregation and oxidation than LF alone. This study demonstrates that ultrasound-assisted formation of protein-polyphenol conjugates can enhance the functional properties of the proteins, thereby extending their application as functional ingredients in nutritionally fortified foods.

Development and application of hydrophilic-hydrophobic dual-protein Pickering emulsifiers: EGCG-modified caseinate-zein complexes.

Zein nanoparticles are commonly used as colloidal emulsifiers to form and stabilize Pickering emulsions. However, the strong surface hydrophobicity of zein nanoparticles limits their widespread application. In this study, composite colloidal emulsifiers were fabricated from zein, sodium caseinate (NaCas), and epigallocatechin gallate (EGCG). Initially, NaCas-EGCG conjugates were formed using either an alkaline or enzymatic method. The enzymatic method led to conjugates containing more EGCG and with a higher thermal stability and surface hydrophilicity. Colloidal emulsifiers were prepared using an antisolvent precipitation method that involved titrating an ethanolic zein solution into an aqueous NaCas-EGCG conjugate solution. The potential application of these emulsifiers for forming and stabilizing high internal phase emulsions (HIPEs) was then explored. The emulsification properties of the zein nanoparticles were improved after they were complexed with NaCas-EGCG conjugates. Pickering HIPEs containing closely packed polygon oil droplets were formed from the colloidal emulsifiers, even at low particle concentrations (0.3% w/v). Overall, our results show that the functional performance of zein nanoparticles can be improved by complexing them with NaCas-EGCG conjugates. The novel colloidal emulsifiers developed in this study may therefore have useful applications in the food and other industries.

Sesamol incorporated cellulose acetate-zein composite nanofiber membrane: An efficient strategy to accelerate diabetic wound healing.

Recently, the function of nanofiber membranes prepared from electrospinning in accelerating wound healing has attracted wide attention. In this study, novel nanofiber membranes consisted of cellulose acetate (CA) and zein were fabricated to provide efficient delivery vehicles for sesamol, and then the effect of sesamol-loaded composite nanofiber membranes on the wound healing of diabetic mice was studied. It was found the critical concentration of CA was between 15% and 25% (w/v), and the most suitable concentration of stabilizing fibers was 22.5%. When the CA/zein ratio was 12:8, the fiber obtained small diameter and uniform distribution, stable intermolecular structure, low infiltration speed and high stability in water. The composite nanofiber membrane with high-dose sesamol (5% of total polymer concentration, w/w) promoted formation of myofibroblasts by enhancing TGF-ß signaling pathway transduction, and promoted keratinocyte growth by inhibiting chronic inflammation in wounds, thus enhancing wound healing in diabetic mice. This study can further broaden the application range of sesamol, CA and zein, and provide reference for the design and development of new wound dressings in the future.

Co-encapsulation of Epigallocatechin Gallate (EGCG) and Curcumin by Two Proteins-Based Nanoparticles: Role of EGCG.

In this study, a novel plant-protein-based nanoparticle delivery system was developed to encapsulate and stabilize curcumin and epigallocatechin gallate (EGCG) with different polarities. The strongly hydrophobic curcumin was embedded within the hydrophobic cores of zein nanoparticles using an antisolvent method, while the weakly hydrophobic EGCG was adsorbed to the region between the zein core and caseinate shell. The physicochemical properties, structure, and stability of the core-shell particles were characterized using dynamic light scattering, particle electrophoresis, fluorescence spectroscopy, and Fourier transform infrared spectroscopy. The bioaccessibility of curcumin in the core-shell nanoparticles was determined using a simulated gastrointestinal tract. Mean particle diameters around 100-200 nm could be produced by modulating the mass ratio of curcumin to zein. The encapsulation efficiency of curcumin in the core-shell nanoparticles was higher (96.2%) in the presence of EGCG than in its absence (77.9%). Moreover, the water dispersibility and 1,1-diphenyl-2-picrylhydrazyl radical scavenging capacity of the nanoparticles were significantly improved in the presence of EGCG. The simulated gastrointestinal tract experiments indicated that curcumin had a high bioaccessibility in the optimized core-shell nanoparticles. Overall, our findings suggest that EGCG can be used to improve the functional properties of curcumin-loaded zein-caseinate nanoparticles, which may increase their use in food, cosmetics, and pharmaceutical applications.

Fabrication and characterization of functional protein-polysaccharide-polyphenol complexes assembled from lactoferrin, hyaluronic acid and (-)-epigallocatechin gallate.

Proteins, polysaccharides, and polyphenols can be assembled into ternary complexes with functional attributes that combine the desirable facets of each individual component. In the present work, we characterized the interactions among lactoferrin (LF), hyaluronic acid (HA) and (-)-epigallocatechin gallate (EGCG) dispersed in aqueous solutions at various pH values (2 to 9), HA levels (0 to 0.5 wt%), and EGCG levels (0 to 0.105 wt%). The antioxidant activity of the complexes was also evaluated. The ternary complexes formed macroscopic hydrogels at pH 2, microgel dispersions at pH 3, and soluble complexes at pH > 4. Information about the role of hydrogen bonds, electrostatic forces, and hydrophobic interactions was obtained using spectroscopic methods. The antioxidant activity of the ternary complexes was much higher at pH 5 than at pH 3, which was attributed to the ability of the hydrogels to inhibit the access of the free radicals generated in the aqueous phase to EGCG trapped inside. These results may be useful for optimizing the formulation of effective delivery systems for natural antioxidants.