Study on the interaction mechanism of whey protein isolate with phosphatidylcholine: By multispectral methods and molecular docking.

The elucidation of the interaction mechanism between phospholipids and milk proteins within emulsions is pivotal for comprehending the properties of infant formula fat globules. In this study, multispectral methods and molecular docking were employed to explore the relationship between phosphatidylcholine (PC) and whey protein isolate (WPI). Observations indicate that the binding constant, alongside thermodynamic parameters, diminishes as temperature ascends, hinting at a predominantly static quenching mechanism. Predominantly, van der Waals forces and hydrogen bonds constitute the core interactions between WPI and PC. This assertion is further substantiated by Fourier transform infrared spectroscopy, which verifies PC's influence on WPI's secondary structure. A detailed assessment of thermodynamic parameters coupled with molecular docking reveals that PC predominantly adheres to specific sites within α-lactalbumin, ß-lactoglobulin, and bovine serum albumin, propelled by a synergy of hydrophobic interactions, hydrogen bonding, and van der Waals forces, with binding energies noted at -5.59, -6.71, and -7.85 kcal/mol, respectively. An increment in PC concentration is observed to amplify the emulsification properties of WPI whilst concurrently diminishing the zeta potential. This study establishes a theoretical foundation for applying the PC-WPI interaction mechanism in food.

Characteristics of soy films as affected by transglutaminase cross-linking and inclusions of pectin and protein enhancers.

Previously, we showed that water extract (soymilk, except pH was increased to 8 from 6.5) of whole soybean could be used directly as a raw material for producing edible soy films by deposition of the film-forming solution (soy extract with enhancers). However, the strength of such soy films needed improvement because they were weak. The purpose of this study was to investigate how transglutaminase (TG) cross-linking reactions and film enhancers, including pectin (low- and high-methoxyl pectin), whey protein isolate (WPI), and soy protein isolate (SPI), improve the physical properties of soy films. Soy films prepared with TG had tensile strength (TS) of 3.01 MPa and puncture strength (PS) of 0.78 MPa, which were higher by as much as 51% and 30% than that of soy films without TG treatment, respectively. Pectin showed significant effects on the mechanical properties of TG-added soy films in terms of TS, PS, and % elongation. On the other hand, only TS and PS were increased by the addition of WPI or SPI. Heat curing had a significant effect on soy film's physical properties. TG treatment significantly reduced film solubility when soaked in water and various levels of acid (vinegar) and base (baking soda) solutions. Under the experimental conditions of 35 unit TG and 28 min of reaction, the degrees of cross-linking were evidenced by the disappearance of individual protein subunits, except the basic subunit of glycinin, and the reduction of 21% of lysine residues of the proteins. HIGHLIGHTS: Edible soy films were made with transglutaminase and about 21% lysine cross-linked. The mechanical strength of soy films was increased by incorporating film enhancers. Transglutaminase enhanced the mechanical properties of soy films.

Whey Protein Sodium-Caseinate as a Deliverable Vector for EGCG: In Vitro Optimization of Its Bioaccessibility, Bioavailability, and Bioactivity Mode of Actions.

Epigallocatechin gallate (EGCG), the principal catechin in green tea, exhibits diverse therapeutic properties. However, its clinical efficacy is hindered by poor stability and low bioavailability. This study investigated solid particle-in-oil-in-water (S/O/W) emulsions stabilized by whey protein isolate (WPI) and sodium caseinate (NaCas) as carriers to enhance the bioavailability and intestinal absorption of EGCG. Molecular docking revealed binding interactions between EGCG and these macromolecules. The WPI- and NaCas-stabilized emulsions exhibited high encapsulation efficiencies (>80%) and significantly enhanced the bioaccessibility of EGCG by 64% compared to free EGCG after simulated gastrointestinal digestion. Notably, the NaCas emulsion facilitated higher intestinal permeability of EGCG across Caco-2 monolayers, attributed to the strong intermolecular interactions between caseins and EGCG. Furthermore, the emulsions protected Caco-2 cells against oxidative stress by suppressing intracellular reactive oxygen species generation. These findings demonstrate the potential of WPI- and NaCas-stabilized emulsions as effective delivery systems to improve the bioavailability, stability, and bioactivity of polyphenols like EGCG, enabling their applications in functional foods and nutraceuticals.

Impact of quercetin conjugation using alkaline and free radical methods with tandem ultrasonication on the functional properties of camel whey and its hydrolysates.

The structural and functional properties of whey-quercetin and whey hydrolysate-quercetin conjugates synthesized using alkaline and free radical-mediated methods (AM and FRM) coupled with sonication were studied. FTIR showed new peaks at 3000-3500 cm-1 (N-H stretching regions) and the 1000-1100 cm-1 region with the conjugates. Conjugation increased the random coils and α-helix content while decreasing the ß-sheets and turns. It also increased the particle size and surface hydrophobicity which was significantly (p < 0.05) higher in AM than FRM conjugates. AM conjugates had higher radical scavenging activity but lower quercetin content than FRM conjugates. Overall, the functional properties of whey-quercetin conjugates were better than whey hydrolysate-quercetin conjugates. However, hydrolysate conjugates had significantly higher denaturation temperatures irrespective of the method of production. Sonication improved the radical scavenging activity and quercetin content of FRM conjugates while it decreased both for AM conjugates. This study suggested that whey-quercetin conjugates generally had better quality than whey hydrolysate conjugates and sonication tended to further improve these properties. This study highlights the potential for using camel whey or whey hydrolysate-quercetin conjugates to enhance the functional properties of food products in the food industry.

Impact of age on the digestion of cream cheese formulated with opposite caseins to whey proteins ratios: An in vitro study.

Ageing leads to changes in the functionality of the digestive tract but the effect of age on digestion and absorption of nutrients remains unclear. The objective of this study was to investigate in vitro the digestion of two high-protein dairy products similar to cream cheese (24 % w/w proteins, 20 % w/w lipids) with opposite casein to whey protein ratios, 80:20 (WP-20), and 20:80 (WP-80). The new static digestion model adapted to the general older adult population (≥65 y.) proposed by INFOGEST was used, as well as the standard version of the protocol. Kinetics of proteolysis and lipolysis were compared between both models for each product, in the gastric and intestinal phases of digestion. In both cream cheeses, the degree of protein hydrolysis (DH-P) was significantly lower for older adults than for young adults at the end of the gastric phase (-19 % for WP-20, and -44 % for WP-80), and at the end of the intestinal phase (-16 % for WP-20, and -20 % for WP-80). The degree of lipid hydrolysis (DH-L) was also significantly lower for older adults than for young adults at the end of the digestion for WP-20 (-30 %), but interestingly it was not the case for WP-80 (similar DH-L were measured). Free fatty acids were also released faster from WP-80 than from WP-20 in both digestion conditions: after 5 min of intestinal digestion DH-L was already ≈32 % for WP-80 against 14 % for WP-20. This was attributed to the opposite casein to whey protein ratios, leading to the formation of different gel structures resulting in different patterns of deconstruction in the gastrointestinal tract. This study highlights the fact that it is essential to carefully consider the composition, structure, and digestibility of foods to develop products adapted to the specific needs of the older adult population.

Micro-encapsulation of garlic oil using esterified-wheat porous starch and whey protein isolate: Physicochemical properties, release behavior during in vitro digestion.

The study aimed to inhibit the stimulating impact of garlic oil (GO) on the stomach and attain high release in the intestine during digestion. So, wheat porous starch (WPS) was modified with octenyl succinic acid (OSA) and malic acid (MA) to obtain esterified WPS, OWPS and MWPS, respectively. The differences in physicochemical, encapsulation, and digestive properties of two GO microcapsules, WPI/OWPS/GO and WPI/MWPS/GO microcapsules produced by using OWPS and MWPS as variant carrier materials and whey protein isolate (WPI) as the same coating agent, were compared. The results found that OWPS had greater amphiphilicity, while MWPS had better hydrophobicity and anti-digestive ability than WPS. Encapsulation efficiency of WPI/OWPS/GO (94.67 %) was significantly greater than WPI/MWPS/GO (91.44 %). The digestion inhibition and low GO release (approximately 23 %) of WPI/OWPS/GO and WPI/MWPS/GO microcapsules in the gastric phase resulted from the protective effect of WPI combined with the good adsorption and lipophilicity of OWPS and MWPS. Especially, WPI/OWPS/GO microcapsule was relatively stable in the gastric phase and had sufficient GO release (67.24 %) in the intestinal phase, which was significantly higher than WPI/MWPS/GO microcapsule (56.03 %), benefiting from the adsorption and digestive properties of OWPS, and resulting in a total cumulative GO release rate of 90.86 %.

Antibacterial mechanism of whey protein isolated-citral nanoparticles and stable synergistic antibacterial eugenol encapsulated Pickering emulsion for grapes preservation.

The purpose of this study was to prepare Pickering emulsion with synergistic antibacterial effect using whey protein isolated-citral (WPI-Cit) nanoparticles with eugenol for grape preservation. In this emulsion, eugenol was encapsulated in oil phase. The particle size, ζ-potential, and antibacterial mechanism of the nanoparticles were characterized. The rheological properties, antibacterial effects and preservation effects of WPI-Cit Pickering emulsion were measured. The results showed that the optimal preparation condition was performed at WPI/Cit mass ratio of 1:1, WPI-Cit nanoparticles were found to damage the cell wall and membrane of bacteria and showed more effective inhibition against S. aureus. Pickering emulsion prepared with WPI-Cit nanoparticles exhibited a better antibacterial effect after eugenol was encapsulated in it, which extended the shelf life of grapes when the Pickering emulsion was applied as a coating. It demonstrated that the Pickering emulsion prepared in this study provides a new way to extend the shelf life.

Composite-structure oleogels constructed by glycerol monolaurate and whey protein isolate: Preparation, characterization and in vitro digestion.

The Glycerol monolaurate (GML) oleogel was induced using Camellia oil by slowly raising the temp to the melting point (MP) of GML. Whey protein isolate (WPI) solution with different ratios was composited with GML oleogel by emulsion template methods, forming dense spines and honeycomb-like networks and impressed with an adjustable composite structure. Textural results showed that compared with single GML-based oleogels, the GML/WPI composite oleogels had the advantages of high hardness and molding, and structural stability. The composite oleogels had moderate thermal stability and maximal oil binding (96.36%). In particular, as up to 6 wt% GML/WPI, its modulus apparent viscosity was significantly increased in rheology and similar to commercial fats. Moreover, it achieved the highest release of FFA (64.07%) and the synergy provided a lipase substrate and reduced the body's burden. The resulting composite oleogel also showed intermolecular hydrogen bonding and van der Waals force interactions. These findings further enlarge the application in the plant and animal-based combined of fat substitutes, delivery of bioactive molecules, etc., with the desired physical and functional properties according to different proportions.

Granular hydrogels with tunable properties prepared from gum Arabic and protein microgels.

Granular hydrogels have emerged as a new class of materials for 3D printing, tissue engineering, and food applications due to their extrudability, porosity, and modularity. This work introduces a convenient method to prepare granular hydrogel with tunable properties by modulating the interaction between gum Arabic (GA) and whey protein isolate (WPI) microgels. As the concentration of GA increased, the appearance of the hydrogel changed from fluid liquid to moldable solid, and the microstructure changed from a macro-porous structure with thin walls to a dense structure formed by the accumulation of spherical particles. At a GA concentration of 0.5 %, the hydrogels remained fluid. Granular hydrogels containing 1.0 % GA showed mechanical properties similar to those of tofu (compressive strength: 10.8 ± 0.5 kPa, Young's modulus: 16.7 ± 0.4 kPa), while granular hydrogels containing 1.5 % GA showed mechanical properties similar to those of hawthorn sticks and sausages (compressive strength: 300.4 ± 5.8 kPa; Young's modulus: 200.5 ± 3.4 kPa). The hydrogel with 2.0 % GA was similar to hawthorn sticks, with satisfactory bite resistance and elasticity. Such tunability has led to various application potentials in the food industry to meet consumer demand for healthy, nutritious, and diverse textures.

Effects of thermal treatment on the formation and properties of whey protein isolate/whey protein hydrolysate-sodium hyaluronate complexes.

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.

Effects of adding proteins from different sources during heat-moisture treatment on corn starch structure, physicochemical and in vitro digestibility.

Proteins impact starch digestion, but the specific mechanism under heat-moisture treatment remains unclear. This study examined how proteins from various sources-white kidney bean, soybean, casein, whey-altered corn starch's structure, physicochemical properties, and digestibility during heat-moisture treatment (HMT). HMT and protein addition could significantly reduce starch's digestibility. The kidney bean protein-starch complex under HMT had the highest resistant starch at 19.74 %. Most proteins effectively inhibit α-amylase, with kidney bean being the most significantly (IC50 = 1.712 ± 0.085 mg/mL). HMT makes starch obtain a more rigid structure, limits its swelling ability, and reduces paste viscosity and amylose leaching. At the same time, proteins also improve starch's short-range order, acting as a physical barrier to digestion. Rheological and low-field NMR analyses revealed that protein enhanced the complexes' shear stability and water-binding capacity. These findings enrich the understanding of how proteins from different sources affect starch digestion under HMT, aiding the creation of nutritious, hypoglycemic foods.

Modulating Whey Proteins Antigenicity with Lactobacillus delbrueckii subsp. bulgaricus DLPU F-36 Metabolites: Insights from Spectroscopic and Molecular Docking Studies.

Numerous studies have highlighted the potential of Lactic acid bacteria (LAB) fermentation of whey proteins for alleviating allergies. Nonetheless, the impact of LAB-derived metabolites on whey proteins antigenicity during fermentation remains uncertain. Our objective was to elucidate the impact of small molecular metabolites on the antigenicity of α-lactalbumin (α-LA) and ß-lactoglobulin (ß-LG). Through metabolomic analysis, we picked 13 bioactive small molecule metabolites from Lactobacillus delbrueckii subsp. bulgaricus DLPU F-36 for coincubation with α-LA and ß-LG, respectively. The outcomes revealed that valine, arginine, benzoic acid, 2-keto butyric acid, and glutaric acid significantly diminished the sensitization potential of α-LA and ß-LG, respectively. Moreover, chromatographic analyses unveiled the varying influence of small molecular metabolites on the structure of α-LA and ß-LG, respectively. Notably, molecular docking underscored that the primary active sites of α-LA and ß-LG involved in protein binding to IgE antibodies aligned with the interaction sites of small molecular metabolites. In essence, LAB-produced metabolites wield a substantial influence on the antigenic properties of whey proteins.

The mechanism of resveratrol stabilization and degradation by synergistic interactions between constituent proteins of whey protein.

Whey protein isolate (WPI) is mainly composed of ß-lactoglobulin (ß-LG), α-lactalbumin (α-LA) and bovine serum albumin (BSA). The aim of this study was to compare and analyze the influence of WPI and its three main constituent proteins, as well as proportionally reconstituted WPI (R-WPI) on resveratrol. It was found that the storage stability of resveratrol was protected by WPI, not affected by R-WPI, but reduced by individual whey proteins at 45°C for 30 days. The rank of accelerated degradation of resveratrol by individual whey proteins was BSA > α-LA > ß-LG. The antioxidant activity, localization of resveratrol and oxidation of carrier proteins were determined by ABTS, H2O2 assay, synchronous fluorescence, carbonyl and circular dichroism. The non-covalent interactions and disulfide bonds between constituent proteins improved the antioxidant activity of the R-WPI-resveratrol complex, the oxidation stability of the carrier and the solvent shielding effect on resveratrol, which synergistically inhibited the degradation of resveratrol in R-WPI system. The results gave insight into elucidating the interaction mechanism of resveratrol with protein carriers.

Digestion of whey peptide induces antioxidant and anti-inflammatory bioactivity on glial cells: Sequences identification and structural activity analysis.

Whey derived peptides have shown potential activity improving brain function in pathological condition. However, there is little information about their mechanism of action on glial cells, which have important immune functions in brain. Astrocytes and microglia are essential in inflammatory and oxidative defense that take place in neurodegenerative disease. In this work we evaluate antioxidant and anti-inflammatory potential bioactivity of whey peptide in glial cells. Peptides were formed during simulated gastrointestinal digestion (Infogest protocol), and low molecular weight (<5kDA) peptides (WPHf) attenuated reactive oxygen species (ROS) production induced by hydrogen peroxide stimulus in both cells in dose-dependent manner. WPHf induced an increase in the antioxidant glutathione (GSH) content and prevented GSH reduction induced by lipopolysaccharides (LPS) stimulus in astrocytes cells in a cell specific form. An increase in cytokine mRNA expression (TNFα and IL6) and nitric oxide secretion induced by LPS was attenuated by WPHf pre-treatment in both cells. The inflammatory pathway was dependent on NFκB activation. Bioactive peptide ranking analysis showed positive correlation with hydrophobicity and negative correlation with high molecular weights. The sequence identification revealed 19 peptides cross-referred with bioactive database. Whey peptides were rich in leucine, valine and tyrosine in the C-terminal region and lysine in the N-terminal region. The anti-inflammatory and antioxidant potential of whey peptides were assessed in glia cells and its mechanisms of action were related, such as modulation of antioxidant enzymes and anti-inflammatory pathways. Features of the peptide structure, such as molecular size, hydrophobicity and types of amino acids present in the terminal region are associated to bioactivity.

Novel Pickering bigels stabilized by whey protein microgels: Interfacial properties, oral sensation and gastrointestinal digestive profiles.

In the ongoing quest to formulate sensory-rich, low-fat products that maintain structural integrity, this work investigated the potential of bigels, especially those created using innovative Pickering techniques. By harnessing the unique properties of whey protein isolate (WPI) and whey protein microgel (WPM) as interfacial stabilizers, WPM-based Pickering bigels exhibited a remarkable particle localization at the interface due to specific intermolecular interactions. The rise in protein concentration not only intensified particle coverage and interface stabilization but also amplified attributes like storage modulus, yield stress, and adhesiveness, owing to enhanced intermolecular forces and a compact gel matrix. Impressively, WPM-based Pickering bigels outshone in practical applications, showcasing exceptional oil retention during freeze-thaw cycles and extended flavor release-a promising indication for frozen food product applications. Furthermore, these bigels underwent a sensory evolution from a lubricious texture at lower concentrations to a stable plateau at higher ones, offering an enriched consumer experience. In a comparative digestibility assessment, WPM-based Pickering bigels demonstrated superior prowess in decelerating the release of free fatty acids, indicating slowed lipid digestion. This study demonstrates the potential to fine-tune oral sensations and digestive profiles in bigels by modulating Pickering particle concentrations.

Multiscale approach to the characterization of the interfacial properties of micellar casein and whey protein blends and their effects on recombined dairy creams.

In this study, whipped cream with blends of micellar casein (MCN) and whey protein (WPI) in different ratios were prepared to investigate the role of protein interfacial behavior in determining foam properties at multiple scales, using theoretical modeling, and microscopic and macroscopic analysis. Fluid force microscopy has been used for the first time as a more realistic and direct means of analyzing interfaces properties in multiphase systems. The adsorption kinetics showed that the interfacial permeability constant of WPI (4.24 × 10-4 s-1) was significantly higher than that of the MCN (2.97 × 10-4 s-1), and the WPI interfacial layer had a higher modulus of elasticity (71.38 mN/m) than that of the MCN (47.89 mN/m). This model was validated via the mechanical analysis of the fat globules in real emulsions. The WPI-stabilized fat globule was found to have a higher Young's modulus (219.67 Pa), which contributes to the integrity of its fat globule morphology. As the ratio of MCN was increased in the sample, however, both the interfacial modulus and Young's modulus decreased. Moreover, the rate of partial coalescence was found to increase, a phenomenon that decreased the stability of the emulsion and increased the rate of aeration. The mechanical analysis also revealed a higher level of adhesion between MCN-stabilized fat globule (25.16 nN), which increased fat globule aggregation and emulsion viscosity, while improving thixotropic recovery. The synergistic effect of the blended MCN and WPI provided the highest overrun, at 194.53 %. These studies elucidate the role of the interfacial behavior of proteins in determining the quality of whipped cream and provide ideas for the application of proteins in multiphase systems.

Effect of enzymatic hydrolysis with Alcalase or Protamex on technological and antioxidant properties of whey protein hydrolysates.

The aim of this study was to evaluate the effect of the enzymatic hydrolysis, performed using Alcalase and Protamex enzymes, on the technological functionalities and the antioxidant capacity of whey protein hydrolysates (WPHs) to identify the conditions allowing to obtain target functionality/ies. Samples were characterized for hydrolysis degree (DH), molecular weight distribution, structural properties, and food-related functionalities. Free sulfhydryl groups and surface hydrophobicity significantly decreased with the increase in DH, regardless of the used enzyme. The foaming and antioxidant properties of Alcalase WPHs were higher as compared to those of WPI, reaching the maximum value at DH = 18-20 %, while higher DH resulted in impaired functionality. Gelling properties were guaranteed when WPI was hydrolysed by Protamex at DH < 15 % while foaming and antioxidant abilities were fostered at 15 < DH < 21 %. These results were well correlated with MW distribution and were rationalized into a road map which represents a useful tool in the selection of proper hydrolysis conditions (time, DH, enzyme type) to obtain WPHs with tailored functionalities. Research outcomes highlighted the possibility to drive protein hydrolysis to optimize the desired functionality/ies.

Droplet size dependency and spatial heterogeneity of lipid oxidation in whey protein isolate-stabilized emulsions.

Spatiotemporal assessment of lipid and protein oxidation is key for understanding quality deterioration in emulsified food products containing polyunsaturated fatty acids. In this work, we first mechanistically validated the use of the lipid oxidation-sensitive fluorophore BODIPY 665/676 as a semi-quantitative marker for local peroxyl radical formation. Next, we assessed the impact of microfluidic and colloid mill emulsification (respectively producing mono- and polydisperse droplets) on local protein and lipid oxidation kinetics in whey protein isolate (WPI)-stabilized emulsions. We further used BODIPY 581/591 C11 and CAMPO-AFDye 647 as colocalisation markers for lipid and protein oxidation. The polydisperse emulsions showed an inverse relation between droplet size and lipid oxidation rate. Further, we observed less protein and lipid oxidation occurring in similar sized droplets in monodisperse emulsions. This observation was linked to more heterogeneous protein packing at the droplet surface during colloid mill emulsification, resulting in larger inter-droplet heterogeneity in both protein and lipid oxidation. Our findings indicate the critical roles of emulsification methods and droplet sizes in understanding and managing lipid oxidation.

Whey protein-loaded 3D-printed poly (lactic) acid scaffolds for wound dressing applications.

Chronic skin wounds pose a global clinical challenge, necessitating effective treatment strategies. This study explores the potential of 3D printed Poly Lactic Acid (PLA) scaffolds, enhanced with Whey Protein Concentrate (WPC) at varying concentrations (25, 35, and 50% wt), for wound healing applications. PLA's biocompatibility, biodegradability, and thermal stability make it an ideal material for medical applications. The addition of WPC aims to mimic the skin's extracellular matrix and enhance the bioactivity of the PLA scaffolds. Fourier Transform Infrared Spectroscopy results confirmed the successful loading of WPC into the 3D printed PLA-based scaffolds. Scanning Electron Microscopy (SEM) images revealed no significant differences in pore size between PLA/WPC scaffolds and pure PLA scaffolds. Mechanical strength tests showed similar tensile strength between pure PLA and PLA with 50% WPC scaffolds. However, scaffolds with lower WPC concentrations displayed reduced tensile strength. Notably, all PLA/WPC scaffolds exhibited increased strain at break compared to pure PLA. Swelling capacity was highest in PLA with 25% WPC, approximately 130% higher than pure PLA. Scaffolds with higher WPC concentrations also showed increased swelling and degradation rates. Drug release was found to be prolonged with increasing WPC concentration. After seven days of incubation, cell viability significantly increased in PLA with 50% WPC scaffolds compared to pure PLA scaffolds. This innovative approach could pave the way for personalized wound care strategies, offering tailored treatments and targeted drug delivery. However, further studies are needed to optimize the properties of these scaffolds and validate their effectiveness in clinical settings.

Adenosine Encapsulation and Characterization through Layer-by-Layer Assembly of Hydroxypropyl-ß-Cyclodextrin and Whey Protein Isolate as Wall Materials.

Adenosine, as a water-soluble active substance, has various pharmacological effects. This study proposes a layer-by-layer assembly method of composite wall materials, using hydroxypropyl-ß-cyclodextrin as the inner wall and whey protein isolate as the outer wall, to encapsulate adenosine within the core material, aiming to enhance adenosine microcapsules' stability through intermolecular interactions. By combining isothermal titration calorimetry with molecular modeling analysis, it was determined that the core material and the inner wall and the inner wall and the outer wall interact through intermolecular forces. Adenosine and hydroxypropyl-ß-cyclodextrin form an optimal 1:1 complex through hydrophobic interactions, while hydroxypropyl-ß-cyclodextrin and whey protein isolate interact through hydrogen bonds. The embedding rate of AD/Hp-ß-CD/WPI microcapsules was 36.80%, and the 24 h retention rate under the release behavior test was 76.09%. The method of preparing adenosine microcapsules using composite wall materials is environmentally friendly and shows broad application prospects in storage and delivery systems with sustained release properties.