Effects of gastrointestinal pH conditions on the stability of the β-lactoglobulin/vitamin D3 complex and on the solubility of vitamin D3

Vitamin-D as a multifunctional molecule for overall well-being: An integrative review

Vitamin D is amongst the most important biomolecules to regularize and help in sustainable health, however, based on the studies, deficiency of this multifunctional vitamin is common. Vitamin D, besides playing a role in the form of vitamins, also acts as a multifunctional hormone (steroid). Vitamin D is synthesized inside the body through various steps starting from ultraviolet radiation exposure and comes from limited food sources, however, vitamin D-fortified food products are still among the major sources of vitamin D. Current review, focused on how vitamin D acts as a multifunctional molecule by effecting different functions in the body in normal or specific conditions and how it is important in fortification and how it can be managed from the available literature till date. During the Covid pandemic, people were aware of vitamin D and took supplementation, fortified foods, and sat under sunlight. As COVID prevalence decreases, people start forgetting about vitamin D. Vitamin D is very crucial for overall well-being as it has protective effects against a broad range of diseases as it can reduce inflammation, cancer cell growth and helps in controlling infection, increase metabolism, muscle, and bone strength, neurotransmitter expression, etc. Therefore, the present review is to provoke the population, and fulfillment of the vitamin D recommended dietary allowance daily must be confirmed.

Vitamin D3 Bioaccessibility from Supplements and Foods-Gastric pH Effect Using a Static In Vitro Gastrointestinal Model

Vitamin D3 deficiency is a global phenomenon, which can be managed with supplementation and food fortification. However, vitamin D3 bioaccessibility may depend on factors such as matrix composition and interactions throughout the gastrointestinal (GI) tract. This research focused on the effect of different matrices on vitamin D3 content during digestion, as well as the effect of pH on its bioaccessibility. The INFOGEST protocol was employed to simulate digestion. Three different types of commercial supplements, two foods naturally rich in vitamin D3, and three fortified foods were investigated. High-Performance Liquid Chromatography was used to determine the initial vitamin D3 content in the supplements and foods, as well as after each digestion stage. The results indicate that the foods exhibited higher bioaccessibility indices compared to the supplements and a higher percentage retention at the end of the gastric phase. The pH study revealed a positive correlation between an increased gastric pH and the corresponding content of vitamin D3. Interestingly, exposing the matrix to a low pH during the gastric phase resulted in an increased intestinal content of D3. Vitamin D3 is more bioaccessible from foods than supplements, and its bioaccessibility is susceptible to changes in gastric pH. Fasting conditions (i.e., gastric pH = 1) enhance the vitamin's bioaccessibility.

Fortification by design: A rational approach to designing vitamin D delivery systems for foods and beverages

Over the past few decades, vitamin D deficiency has been recognized as a serious global public health challenge. The World Health Organization has recommended fortification of foods with vitamin D, but this is often challenging because of its low water solubility, poor chemical stability, and low bioavailability. Studies have shown that these challenges can be overcome by encapsulating vitamin D within well-designed delivery systems containing nanoscale or microscale particles. The characteristics of these particles, such as their composition, size, structure, interfacial properties, and charge, can be controlled to attain desired functionality for specific applications. Recently, there has been great interest in the design, production, and application of vitamin-D loaded delivery systems. Many of the delivery systems reported in the literature are unsuitable for widespread application due to the complexity and high costs of the processing operations required to fabricate them, or because they are incompatible with food matrices. In this article, the concept of "fortification by design" is introduced, which involves a systematic approach to the design, production, and testing of colloidal delivery systems for the encapsulation and fortification of oil-soluble vitamins, using vitamin D as a model. Initially, the challenges associated with the incorporation of vitamin D into foods and beverages are reviewed. The fortification by design concept is then described, which involves several steps: (i) selection of appropriate vitamin D form; (ii) selection of appropriate food matrix; (iii) identification of appropriate delivery system; (iv) identification of appropriate production method; (vii) establishment of appropriate testing procedures; and (viii) system optimization.

Different interactions driving the binding of soy proteins (7S/11S) and flavonoids (quercetin/rutin): Alterations in the conformational and functional properties of soy proteins

The purpose of this research was to comparatively investigate the interactions between bioactive flavonoids (quercetin and rutin) and two predominant soy proteins (β-conglycinin and glycinin), and the structural and functional properties of their complexes. The binding affinities of quercetin/rutin toward 7S/11S were structure-dependent, in that rutin had a higher binding affinity than that of quercetin, and 11S exhibited higher affinity toward quercetin/rutin than that of 7S. The interactions in the 7S/11S-quercetin complexes were driven by van der Waals forces and hydrogen-bonding interactions, whereas the 7S/11S-rutin complexes exhibited hydrophobic interactions. Binding to quercetin or rutin altered the secondary structures (decrease in the α-helix and random coil contents and increase in the β-sheet content), decreased the surface hydrophobicity and thermal stability, and enhanced the antioxidant capacity of 7S and 11S. These findings provide valuable information that can facilitate the design of custom-tailored protein-flavonoid macromolecules.

Development of functional whey cheese enriched in vitamin D3: nutritional composition, fortification, analysis, and stability study during cheese processing and storage

"Ricotta" cheese is a traditional and popular Italian fresh whey cheese commonly produced from cow's milk. Food fortification is an efficient strategy to reduce the high global prevalence of vitamin D deficiency. This study aims to study the chemical-nutritional analysis of ricotta cheese and to assess its suitability as a dairy matrix for vitamin D fortification. The chemical-nutritional analyses revealed that ricotta cheese is a good source of proteins (7.8 g/100 g) with high levels of branched-chain amino acids (1.8 g/100 g). Moreover, ricotta contains high levels of calcium (0.4 g/100 g) and phosphorus (0.2 g/100 g). 50 mg of vitamin D₃ were added to 95 kg of cheese reaching a mean fortification level of 41.4 ± 4.0 µg/100 g of ricotta cheese. The fortification study showed that vitamin D homogenously distributes in ricotta cheese after the homogenisation process. Moreover, vitamin D₃ has high heat stability (93.8 ± 1.8%) and remains stable throughout the shelf-life of the fortified food. This study demonstrates that ricotta cheese represents an ideal alternative dairy matrix for vitamin D₃ fortification.

Vitamin D3 cress seed mucilage -β-lactoglobulin nanocomplexes: Synthesis, characterization, encapsulation and simulated intestinal fluid in vitro release

Vitamin D₃ (VD₃) as an essential lipid-soluble active ingredient with numerous applications in food and pharmaceutical sectors; however, poor water solubility reduces its bioavailability significantly. Application of protein-polysaccharide complexes as a promising way to protect and trigger programmed release of bioactive molecules has established an optimal window in nutraceutical delivery systems. In this study, complexes of β-lactoglobulin (Blg) and cress seed mucilage (CSM) were used to retain VD₃ at undesirable circumstances, such as acidic pH values. The interaction of CSM-Blg was studied by rheological tests and the best formulation was chosen for encapsulation of VD₃ via crosslinking with calcium ions (2-10 mM). The results demonstrated that complexation protect VD₃ at low pH values with the maximum encapsulation efficiency of 84.2 %. The in vitro study indicated that Blg-CSM-VD₃ was more stable in simulated gastric fluid, and in turn VD₃ was released in simulated intestinal fluid; the complexes treated with calcium ions had a slower release rate than normal complexes. The release trend of VD₃ followed the diffusion-Fickian law and the principal interactions included hydrophobic, electrostatic and hydrogen bonding. The results indicated that Blg-CSM complexes can retain VD₃ at acidic environment and induce sustained release, which brings about practical advantages for vitamin delivery in the food and pharmaceutical sectors.

Insights on Health and Food Applications of Equus asinus (Donkey) Milk Bioactive Proteins and Peptides-An Overview

Due to its similarity with human milk and its low allergenic properties, donkey milk has long been used as an alternative for infants and patients with cow's milk protein allergy (CMPA). In addition, this milk is attracting growing interest in human nutrition because of presumed health benefits. It has antioxidant, antimicrobial, antitumoral, antiproliferative and antidiabetic activity. In addition, it stimulates the immune system, regulates the gastrointestinal flora, and prevents inflammatory diseases. Although all donkey milk components can contribute to functional and nutritional effects, it is generally accepted that the whey protein fraction plays a significant role. This review aims to highlight the active proteins and peptides of donkey milk in comparison with other types of milk, emphasizing their properties and their roles in different fields of health and food applications.

Co-encapsulation of vitamins B12 and D3 using spray drying: Wall material optimization, product characterization, and release kinetics

Spray drying is the most commonly used encapsulation technique to stabilize sensitive bioactive compounds and sometimes enhances their performance. Vitamin B₁₂ and vitamin D₃ deficiencies are reported worldwide and co-encapsulation can provide a combined solution to this problem. The present work aimed at encapsulation of vitamin B₁₂ and D₃ by spray drying using experimental design to optimize wall material combination. Optimized solution obtained from the experimental design (gum acacia : Hi-Cap® 100 : maltodextrin = 38:60:2) provided spherical particles with smooth surface and better stability of both the vitamins. In vitro release mechanism showed a slow release for both the vitamins after encapsulation. The optimized co-encapsulated microcapsules obtained in this work showed an improved bioavailability of 151% for vitamin B₁₂ and 109% for vitamin D₃ in comparison with the control. This study delivered a suitable medium to provide water soluble vitamin B₁₂ and fat soluble vitamin D₃ in single product.

Gastrointestinal digestion enhances the endothelium-dependent vasodilation of a whey hydrolysate in rat aortic rings

Whey proteins present encrypted biofunctional peptides that need to be released from the native protein to exert their biological activity. Antihypertensive whey peptides are the most studied ones, which can be explained by high prevalence of this chronic degenerative disease. The present study investigated whether the molecular changes occurred during the gastrointestinal digestion of a whey protein hydrolysate could modulate its vasorelaxant potential in rat aortic rings. Spectrophotometric data and SDS-PAGE gel showed a small degree of hydrolysis during the gastric phase and intense intestinal proteolysis. RP-HPLC revealed the formation of a large peptide profile. During the simulated digestion, 198 peptides were generated and identified and, left-shifted the concentration-response curve of the endothelium-dependent vasorelaxation, as recorded for the digested hydrolysates. In conclusion, gastrointestinal digestion of the whey hydrolysate leads to the generation of bioactive peptides with enhanced vasodilatory potency, reinforcing the relevance of whey-derived products in blood pressure regulation.

Atomization of denatured whey proteins as a novel and simple way to improve oral drug delivery system properties

In the sphere of drug delivery, denatured whey protein (DWP) has in recent times gained press. However, to date, no scalable and affordable dosage form has been developed. The objective of our study was to evaluate the potential use of spray-dried DWP as a ready to use excipient for oral drug delivery. Therefore, solid state, FTIR spectra and wettability were studied. Dissolution, mucoadhesion and the effect on paracellular permeability were also evaluated. The spray-dried DWP particles were spherical with 4μm mean diameter. Further, relative to native WP, the spray-dried DWP particles bore reduced wettability, and their structure was characterized by the exposure of a high amount of free thiol and by the formation of intermolecular β-sheets. The DWP powders were mucoadhesive, enzymatic inhibitors, biocompatible and they induced the opening of tight junctions. Our study shows great potential for the use of spray-drying as a technique to modify the dissolution rate of drugs and enhance the oral bioavailability of molecules. That is, the use of spray drying as a single step ready to use DWP excipient.

Interaction between 2-(p-toluidino)-6-naphthalenesulfonic acid sodium salt (TNS) and β-lactoglobulin

The major bovine milk protein β-lactoglobulin (β-LG), a member of the lipocalin superfamily, can bind a wide range of ligands and act as a transporter. In the present study, the combination of the hydrophobic molecule 2-(p-toluidino)-6-naphthalenesulfonic acid sodium salt (TNS) with β-LG was analyzed using fluorescence spectroscopy and AutoDock modeling to discern the major binding sites of the protein and to determine the capacity of other small ligands to bind with β-LG by utilizing TNS as a reference. The experimental data indicate that in a neutral pH environment, TNS is located in the hydrophobic domain of the protein, 2.5 nm away from the Trp19 residues of β-LG. The binding constant of the small molecule to β-LG is (3.30 ± 0.32) × 106 (mol L–1)−1. An interaction model between the ligand and β-LG was developed, and AutoDock modeling also demonstrates that the ligand is located in the central hydrophobic calyx of β-LG within the regions covered by the Förster radius of the Trp19–ligand pair. Although the interaction between the ligand and β-LG is affected by increasing ion strength, pH change, and heat treatment, the complex is maintained until the secondary structure of β-LG is destroyed. Additionally, the ligand binding stabilizes the folding of β-LG. The binding constants of sodium dodecyl sulfate (SDS) and sodium dodecylbenzene sulfonate (SDBS) to β-LG were obtained using competitive ligand binding measurements. With a sensitive fluorescence signal and stable complex, the ligand could be utilized as a reference to detect the binding of other small ligands to β-LG.

Designing food delivery systems: challenges related to the in vitro methods employed to determine the fate of bioactives in the gut

This review discussesin vitroavailable approaches to study delivery and uptake of bioactive compounds and the associated challenges.