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Polysaccharide‐protein multilayers (PPMLs) consisting of bovine serum albumin (BSA) and chondroitin sulfate (CS) are assembled in acidic solution (pH 4.2) via layer‐by‐layer deposition method. The formation of PPMLs on gold surface and their responsiveness to pH change from 4.2 to 7 is investigated by Surface Plasmon Resonance Spectroscopy. The buildup of the multilayer at pH 4.2 exhibits non‐linear growth while the formation of the first layers is strongly affected by the physicochemical properties of the gold surface. Neutral solution (pH 7) affects the interactions between the biopolymers and results in a partially disassemble (disintegration) of the multilayer film. On one hand, the single pair of layers, BSA‐CS and the double pair of layers, (BSA‐CS)2, assemblies are stable in neutral pH, a result that will be of interest for biomedical applications. On the other hand, multilayer films consisting of more than four layers that is (BSA‐CS)2

Macrophages are the most abundant cell group in atherosclerosis (AS) lesions and play a vital role in all stages of AS progression. Recent research has shown that reactive oxygen species (ROS) generation from photodynamic therapy (PDT) induces macrophage autophagy to improve abnormal lipid metabolism and inflammatory environment. Especially in macrophage-derived foam cells, which has become a potential strategy for the treatment of AS. In this study, we prepared the conjugate (DB) of dextran (DEX) and bovine serum albumin (BSA). The DB was used as the emulsifier to prepare nanoemulsion loaded with upconversion nanoparticles (UCNPs) and chlorin e6 (Ce6) (UCNPs-Ce6@DB). The DEX modified on the surface of the nanoemulsion can recognise and bind to the scavenger receptor class A (SR-A) highly expressed on macrophages and promote the uptake of macrophage-derived foam cells in AS plates through SR-A-mediated endocytosis. In addition, UCNPs-Ce6@DB-mediated PDT enhanced ROS generation and induced autophagy in macrophage-derived foam cells, enhanced the expression of ABCA 1, a protein closely related to cholesterol efflux, and inhibited the secretion of pro-inflammatory cytokines. Ultimately, UCNPs-Ce6@DB was shown to inhibit plaque formation in mouse models of AS. In conclusion, UCNPs-Ce6@DB offers a promising treatment for AS. [ABSTRACT FROM AUTHOR]

[Display omitted] • Thermal treatment altered WPI/WPH structure and promoted their interaction with SH. • The formation of WPI-SH and WPH-SH enhanced the thermal stability of proteins. • The formation of WPI-SH and WPH-SH complexes reduced the antigenicity of proteins. In dairy products, the added sodium hyaluronate may form complexes with proteins, thereby affecting product properties. In the present study, the interaction between whey protein isolate (WPI)/ whey protein hydrolysate (WPH) and sodium hyaluronate (SH) was characterized under thermal treatment at different temperatures (25 ℃, 65 ℃, 90 ℃ and 121 ℃) after studying effects of protein/SH ratio and pH on complex formation. The addition of SH reduced the particle size of WPI/WPH and increased potential value in the system, with greater variation with increasing treatment temperature. The structural properties of complexes were studied. The binding with SH decreased the contents of free amino group and free thiol group, as well as the fluorescence intensity and surface hydrophobicity. FTIR results and browning intensity measurement demonstrated the formation of Maillard reaction products. Moreover, the attachment of SH improved the thermal stability of WPI/WPH and decreased their antigenicity. [ABSTRACT FROM AUTHOR]

The protein-polysaccharide nanofibers have attracted intensive attention in promoting wound healing, due to their components and nanoscale fibrous structure that mimics the native extracellular matrix (ECM). For the full-thickness wounds, in addition to promoting healing, hemostatic property and antibacterial activity are also of critical importance. However, currently, protein-polysaccharide-based nanofiber membranes exhibit poor mechanical properties, lack inherent hemostatic and antibacterial capabilities, as well as the ability to promote tissue repair. In this study, we developed composited membranes, which were composed of collagen (Col) and chitosan (Chs), through solvent alteration and post-processing, the membranes showed enhanced stability under physiological conditions, proper hydrophilic performance and improved mechanical property. Appropriated porosity and water vapor transmission rate, which benefit to wound healing, were detected among all the membranes except for Col membrane. Aimed at wound dressing, hemocompatibility, antibacterial activity and cell proliferation of the electrospun membranes were evaluated. The results indicated that the Col/Chs composited membranes exhibited superior blood clotting capacity, and the membranes with Chs exceeding 60% possessed sufficient antibacterial activity. Moreover, compared with Chs nanofibers, significant increase in cell grow was detected in Col/Chs (1:3) membrane. Taken together, the electrospun membrane with multiple properties favorable to wound healing, superior blood coagulation, sufficient antibacterial performance and promoting cell proliferation property make it favorable candidate for full-thickness skin wound healing., (© 2024 IOP Publishing Ltd.)

The protein–polysaccharide combinations that lead to electrostatic complex and coacervate formation are the object of extensive research using both layer-by-layer and mixed emulsion approaches. The protein–polysaccharide conjugates demonstrated interesting physicochemical properties as stabilizers and emulsifiers, as well as texture modifiers in food products. Furthermore, they are potential optimal nutrient delivery systems. Their complex behavior due to several factors such as pH, ionic strength, concentration, heat, and mechanical treatments is the main reason behind the continuous growth of the research field. The review is reporting some recent advances on the topic, along with an overview of the possible interactions between protein and polysaccharide, from Maillard reaction to enzymatic cross-linking passing through coacervates. [ABSTRACT FROM AUTHOR]

• Nano-encapsulation significantly improved the water solubility of curcumin. • The interaction of curcumin and zein through hydrogen bonding. • Binding of coating material to zein nanoparticles resulted in increased apparent viscosity. • The excellent stability of nanoparticles own to the electrosteric stabilization provided by sodium alginate. Curcumin is a polyphenol with multiple biological activities, but its extremely poor water solubility severely limits its application in the food industry. The purposes of this work were to study the effect of nano-encapsulation on the water solubility of curcumin (C), the interaction of curcumin with zein (Z), the thermal properties, rheological properties, and the stability under different environmental pressures of the nanoparticles. The results of particle size, zeta potential, and surface hydrophobicity (H 0) indicated that the combination of coating materials including sodium caseinate (SC) and sodium alginate (SA) with zein nanoparticles by electrostatic interaction led to a gradual increase in the particle size of composite nanoparticles and a decrease in surface hydrophobicity. The nano-encapsulation significantly improved the water solubility of curcumin and causing its crystal structure to change to an amorphous state. Fourier transform infrared spectroscopy confirmed that curcumin bound to zein through hydrogen bonding. Rheological test results showed that the coating materials combined with zein led to an increase in the apparent viscosity of the nanoparticles. The stability analysis results indicated that the composite nanoparticles with a sodium alginate coating have excellent stability of pH, salt solution and storage, and excellent anti-gastrointestinal fluids digestion characteristics when compared to pure protein nanoparticles. [ABSTRACT FROM AUTHOR]

A single emulsifier material is seldom sufficient to cater to the requirements of complex emulsion-based food formulations that have to function over a wide range of pH, ionic strength, storage time, and temperature. Food emulsions have to be designed to satisfy several requirements for use which could be achieved by combining the beneficial properties of multiple emulsifiers. The present article reviews novel biological materials that are used to design oil-in-water (o/w) emulsions. More specifically, the major focus is to discuss (o/w) interfaces stabilized by multiple biopolymers. Prevalent ways by which two or more emulsifiers could be combined is by (i) forming multi-layered emulsions and (ii) conjugation of two compounds of beneficial traits. Multilayer emulsions make use of a combination of protein, phospholipids, and carbohydrates to stabilize (o/w) interfaces. On the other hand, covalent bonding between a protein and polysaccharide is induced to form a single entity known as conjugate that is superior to the individual biopolymers in terms of emulsion stability. Therefore, properties required to maintain emulsion stability such as surface activity, solubility, steric and electrostatic repulsion, and antioxidant effects from two different hydrocolloids could be integrated. [ABSTRACT FROM AUTHOR]

Polysaccharides are often used as rheology modifiers in multiphasic protein-rich food systems. Recently, proteinaceous microgels have garnered research attention as promising lubricating agents. However, whether proteinaceous microgels can be used to replace polysaccharides in a tribological context remains poorly understood. In this study we compared the flow and oral-tribological behaviour of Newtonian solutions of the polysaccharide dextran (D, 1–11 wt%) when combined with a dispersion of whey protein isolate (W, 1–13 wt%) or whey protein microgels (WPM, 41.7 vol%) and compared with microgels of D conjugated to W (Conj(D[11] + W[5])MG) or dispersions of WPM in W solutions. W and WPM alleviated frictional forces between elastomeric surfaces as well as biomimetic tongue-like surfaces in the boundary lubrication regime. Despite the negligible influence of D on the thin-film lubricity, its impact on viscous-facilitated lubricity was significant. The importance of measurements with the tongue-mimicked setup emerged where Conj(D[11] + W[5])MG did not show significant lubricity enhancement despite its outstanding performance with conventional tribo-testing setups. By optimising a combination of WPM and non-microgelled W, we demonstrate that a combined viscous and thin-film lubricity could be achieved through a single-protein-component without the need of polysaccharides. The dispersions of WPM (41.7 vol%) deliver the same flow and viscous-friction behaviour to that of 5 wt% D and excel in thin-film lubricity. These findings pave the way towards design of processed foods with clean labels, taking advantage of using a single proteinaceous moiety whilst delivering enhanced lubricity and viscosity modification without the need of any additional thickener. [Display omitted] • Whey protein microgels (WPM) provide fluid-film and boundary lubricity. • WPM (41.7 vol%) deliver the same thickening behaviour as dextran (D) at 5 wt%. • WPM can be used as replacer for thickeners and lubrication-enhancer, simultaneously. • Microgels of D-conjugated whey protein deliver superlubricity upon entrained. • Superlubricity of conjugated microgels disappeared in a tongue-mimicked tribometer. [ABSTRACT FROM AUTHOR]

Proteins and polysaccharides are common ingredients in food products. In many food formulations, proteins and polysaccharides (two major biopolymers) are used simultaneously. Understanding their interactions can help controlling physical properties and stability of formulated foods. Interactions between β-lactoglobulin (BLG) and tragacanth gum (TG) were studied in aqueous solutions at pH ranging from 3.5 to 5.5 and at different biopolymers concentrations. BLG and TG solutions were prepared in distilled water under gentle stirring at 20°C. Different biopolymers concentrations were mixed and pH value were adjusted by HCl. Absorbance of the mixtures were measured at 650 nm using UV-Visible spectrophotometer. The measured absorbances were plotted against pH. In this study, pHC, pHφ, and pHopt were identified and measured for different biopolymers concentrations. Phase separation observed during experiments is an associative phase separation. Complex sizes increased between pHC and pHφ because of soluble complexes formation and then a decrease in complex sizes was observed and this decrease was due to neutralization of initiate complexes and solubilization of biopolymers complexes. This wide range of complex formation helps product developer to use tragacanth gum in a large range of formulations. [ABSTRACT FROM AUTHOR]

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The immunomodulating activity of Kp, an antitumor protein-polysaccharide preparation from the shake-cultured mycelia of Phellinus linteus, was investigated in ICR mice subcutaneously implanted with 1×10 cells of sarcoma 180. The mice were intraperitoneally administered with Kp at a dose of 100 mg/kg once daily for five consecutive days starting from 24 hrs after the tumor implantation. Ten days after the last injection, the mice were immunized with 1×10 or 4×10 sheep red blood cells (SRBC) and five days later, the antibody-forming immune response were assessed by direct hemolytic plaque assay. To an immunization dose of 1×10 SRBC, the Kp-treated mice elicited a successful humoral immune response despite the tumor-burden and produced 259×10 plaque-forming cells (PFC)/spleen, while the corresponding tumor-bearing control mice showed virtually no response (2.0×10 PFC/spleen) (the stimulation index=129.5). However, to an immunization dose of 4×10 SRBC, both of the control mice and Kp-treated mice showed almost the same level of strong humoral immune response. From these data it is clear that Kp effectively restores the humoral immune response of the tumor-bearing ICR mice. [ABSTRACT FROM AUTHOR]