The Layered Encapsulation of Vitamin B2 and β-Carotene in Multilayer Alginate/Chitosan Gel Microspheres: Improving the Bioaccessibility of Vitamin B2 and β-Carotene

Preparation of pH-enzyme dual-responsive gel microspheres and their treatment of ulcerative colitis

Mesalazine (MSZ), a first-line treatment for ulcerative colitis (UC), was formulated into acid-resistant, colon-targeted gel microspheres to reduce upper gastrointestinal tract (GIT) exposure and extend drug retention in the colon. In this study, we used MSZ/hydroxypropyl-β-cyclodextrin (MSZ/HP-β-CD) as the model drug, dopamine-modified sodium alginate (DA-SA) and konjac glucomannan (KGM) as the carrier matrix, and chitosan (CS) as the coating material. The colon-targeted gel microspheres (MSZ/HP-β-CD/DA-SA/KGM/CS) were prepared using the drop method. These microspheres had a drug loading capacity of 7.9 ± 0.01 % and an encapsulation efficiency of 72.5 ± 0.03 %. The drug primarily released in the colon environment, showing pH and β-mannanase sensitivity. The dried microspheres measured approximately 0.6 mm, suitable for oral administration. In the rat UC model, after oral administration of gel microspheres, the colon length increased, while the DAI score, spleen index, and the expression levels of IL-6, IL-1β, TNF-α, TLR4, MyD88 and NF-κB p65 all decreased. Histopathological examination showed that treated UC rats' colon tissues closely resembled those of healthy controls. These findings indicate that pH-enzyme-responsive coated gel microspheres can effectively target the colon and show potential for UC treatment.

Mechanism of the Discontinuous Structure in Heat-Induced Natural Egg Yolk Mediated by Accumulation of Yolk Sphere Microgels: Morphology, 4D-DIA Proteomics, and Physicochemical Properties

The heat-induced natural egg yolk is a discontinuous object formed by the accumulation of yolk spheres. However, the reason why yolk spheres form individual microgels rather than continuous gels has not been elucidated. This study investigated the different gelation behaviors in the yolk sphere exterior (EYSE) and the yolk sphere interior (EYSI) by using 4D-DIA proteomics, electron microscopy, and multispectral techniques. Results demonstrated that vitellogenin-1, -2, and -3 (EYSI/EYSE fold change: 3.36, 3.53, and 2.42, respectively) were key proteins corresponding to continuous gel structure formation of EYSI. However, the high levels of apolipoprotein A-I (FC: 0.18) and heat shock protein found in EYSE with a special hydrophobic domain for lipid binding impeded the continuous gel formation. Thus, the EYSE formed some small-volume aggregates without continuous gel, which separated individually the microgel of yolk spheres. This study will provide theoretical guidance for the quality regulation of egg yolk products.

Nanoencapsulation of vitamin B2 using chitosan-modified poly(lactic-co-glycolic acid) nanoparticles: Synthesis, characterization, and in vitro studies on simulated gastrointestinal stability and delivery

Vitamin B2, or riboflavin, is essential for maintaining healthy cellular metabolism and function. However, its light sensitivity, poor water solubility, and gastrointestinal barriers limit its storage, delivery, and absorption. Selecting suitable nanomaterials for encapsulating vitamin B2 is crucial to overcoming these challenges. This study employed chitosan-coated poly(lactic-co-glycolic acid) nanoparticles (CS-PLGA NPs) as a novel delivery system to enhance the bioavailability of vitamin B2 for food fortification and nutraceutical applications. The nanoparticles, with sizes below 200 nm, exhibited greater stability than PLGA NPs after freeze-drying and in simulated body fluids. Encapsulation improved the photostability of vitamin B2 under ultraviolet light and prolonged its release in simulated body fluids compared to non-encapsulated vitamin B2. Furthermore, CS-PLGA NPs demonstrated higher uptake in intestinal epithelial cells (Caco-2), indicating enhanced transport and potential for use in fortified food systems. These findings underscore the promise of CS-PLGA NPs for delivering vitamin B2 in food, nutraceutical, and pharmaceutical applications. PRACTICAL APPLICATION: The use of chitosan-coated PLGA NPs for encapsulating vitamin B2 offers a promising solution to enhance its bioavailability, especially for individuals with gastrointestinal absorption issues. This formulation improves stability, controlled release, and cellular uptake, which can lead to more effective supplementation strategies in nutraceutical and pharmaceutical applications. It could benefit patients with vitamin B2 deficiencies, such as those with malabsorption disorders, by ensuring efficient delivery through the gastrointestinal tract. Additionally, this approach can be applied to other water-soluble vitamins or bioactive compounds, offering a versatile platform for improving the efficacy of oral supplements.

Novel pH-sensitive gellan gum-ε-polylysine hydrogel microspheres for sulforaphene delivery

BACKGROUND

This study aimed to improve the stability and utilization of sulforaphene (SFE) and to enhance the intestinal stability and pH-sensitive release of SFE in the gastrointestinal tract. To achieve this objective, calcium chloride (CaCl2) was used as a crosslinking agent to fabricate novel SFE-loaded gellan gum (GG)-ε-polylysine (ε-PL) pH-sensitive hydrogel microspheres by using the ionic crosslinking technique.

RESULTS

The molecular docking results of GG, ε-PL, and SFE were good and occurred in the natural state. The loading efficiency (LE) of all samples was above 70%. According to the structural characterization results, GG and ε-PL successfully embedded SFE in a three-dimensional network structure through electrostatic interaction. The swelling characteristics and in vitro release results revealed that the microspheres were pH-sensitive, and SFE was mainly retained inside the hydrogel microsphere in the stomach, and subsequently released in the intestine. The result of cytotoxicity assay showed that the hydrogel microspheres were non-toxic and had an inhibitory effect on human colon cancer Caco-2 cells.

CONCLUSION

Thus, the hydrogel microspheres could improve SFE stability and utilization and achieve the intestinal targeted delivery of SFE. © 2024 Society of Chemical Industry.

Bioactive compounds delivery and bioavailability in structured edible oils systems

The health benefits of bioactive compounds are dependent on the amount of intake as well as on the amount of these compounds that become bioavailable and bioaccessible. Various systems have been developed to deliver and increase the bioaccessibility of bioactive compounds. This review explores the impact of gelled (oleogels, bigels, emulgels, emulsions, hydrogels, and hydrogel beads), micro-(gels, particles, spheres, capsules, emulsions, and solid lipid microparticles) and nanoencapsulated systems (nanoparticles, solid lipid nanoparticles, nanostructured lipid carriers, nanoemulsions, liposomes, and nanoliposomes) on the digestibility and bioavailability of lipophilic and hydrophilic bioactives. Structurant molecules, the oil type, antioxidants, emulsifiers, and coatings in delivery systems with promising potential in food applications are critically discussed. The release and bio-accessibility of bioactive compounds in gelled systems are influenced by various factors, such as the type and concentration of gelators, the gelator-to-oil ratio, the type of antioxidant, the network of the system, and its hydrophobicity. The stability, bioaccessibility, and controlled release of bioactives were improved in structured emulsions. Several variables, including wall material, oil/water ratios, encapsulation process, and pH conditions, can affect the bioactives release in microencapsulated systems. Factors like coating type and core-to-wall ratio impact the stability and release of core components. The encapsulating material, the encapsulation technology, and the nature of the nanomaterials all have an impact on the bioaccessibility of nanoencapsulated systems. Nanoliposomes provide enhanced stability and absorption. In general, all encapsulated systems have shown great potential in improving the distribution and availability of bioactive compounds.

Synthesis and characterization of ion-induced sodium alginate/soy protein isolate microgels for the controlled release

In this study, sodium alginate/ soy protein isolate (SPI) microgels cross-linked by various divalent cations including Cu2+, Ba2+, Ca2+, and Zn2+ were fabricated. Cryo-scanning electron microscopy observations revealed distinctive structural variations among the microgels. In the context of gastric pH conditions, the degree of shrinkage of the microgels followed the sequence of Ca2+ > Ba2+ > Cu2+ > Zn2+. Meanwhile, under intestinal pH conditions, the degree of swelling was ranked as Zn2+ > Ca2+ > Ba2+ > Cu2+. The impact of these variations was investigated through in vitro digestion studies, revealing that all microgels successfully delayed the release of β-carotene within the stomach. Within the simulated intestinal fluid, the microgel cross-linked with Zn2+ exhibited an initial burst release, while those cross-linked with Cu2+, Ba2+, or Ca2+ displayed a sustained release pattern. This research underscores the potential of sodium alginate/SPI microgels cross-linked with different divalent cations as efficient controlled-release delivery systems.

Development of a tobramycin-loaded calcium alginate microsphere/chitosan composite sponge with antibacterial effects as a wound dressing

Traditional dressings exhibit several disadvantages, as they frequently lead to bacterial infections, cause severe tissue adhesion and perform a relatively single function. Therefore, in this study, a composite sponge dressing with antibacterial properties and excellent physicochemical properties was developed. Six groups of tobramycin-loaded calcium alginate microspheres were prepared by changing the amount of tobramycin added, and the optimal group was selected. Then, seven groups of tobramycin-loaded calcium alginate microsphere/chitosan composite sponges were fabricated via a solvent blending process and a freeze-drying method. The surface morphology, physicochemical properties,in vitrodegradation properties,in vitrodrug release properties, antibacterial properties and cytotoxicity of the composite sponges were examined. Group 3.0 contained the best microspheres with the largest drug loading capacity, good swelling performance and cumulative drug release rate, obvious and sustained antibacterial activity, and good cytocompatibility. The tobramycin-loaded calcium alginate microsphere/chitosan composite sponges exhibited three-dimensional porous structures, and their porosity, swelling rate, water absorption and water retention rates and water vapor transmission rate met the standards needed for an ideal dressing. The comprehensive performance of the sponge was best when 20 mg of drug-loaded microspheres was added (i.e. group 20). The cumulative drug release rate of the sponge was 29.67 ± 4.14% at 7 d, the diameters of the inhibition zones against the three bacteria were greater than 15 mm, and L929 cell proliferation was promoted. These results demonstrated that the tobramycin-loaded calcium alginate microsphere/chitosan composite sponge with 20 mg of tobramycin-loaded microspheres shows promise as a dressing for infected wounds.

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

Delivery Systems to Enhance Bioaccessibility and Bioavailability of Bioactive Factors: Structure, Property, and Food Applications

Incorporating bioactive factors to strengthen food nutrition is important for functional food development [...].

Alginate Gel-Based Carriers for Encapsulation of Carotenoids: On Challenges and Applications

Sodium alginate is one of the most interesting and the most investigated and applied biopolymers due to its advantageous properties. Among them, easy, simple, mild, rapid, non-toxic gelation by divalent cations is the most important. In addition, it is abundant, low-cost, eco-friendly, bio-compatible, bio-adhesive, biodegradable, stable, etc. All those properties were systematically considered within this review. Carotenoids are functional components in the human diet with plenty of health benefits. However, their sensitivity to environmental and process stresses, chemical instability, easy oxidation, low water solubility, and bioavailability limit their food and pharmaceutical applications. Encapsulation may help in overcoming these limitations and within this review, the role of alginate-based encapsulation systems in improving the stability and bioavailability of carotenoids is explored. It may be concluded that all alginate-based systems increase carotenoid stability, but only those of micro- and nano-size, as well as emulsion-based, may improve their low bioaccessibility. In addition, the incorporation of other biopolymers may further improve encapsulation system properties. Furthermore, the main techniques for evaluating the encapsulation are briefly considered. This review critically and profoundly explains the role of alginates in improving the encapsulation process of carotenoids, suggesting the best alternatives for those systems. Moreover, it provides a comprehensive cover of recent advances in this field.

Development and Evaluation of Cross-Linked Alginate-Chitosan-Abscisic Acid Blend Gel

Abscisic acid (ABA) has been proposed to play a significant role in the ripening of nonclimacteric fruit, stomatal opening, and response to abiotic stresses in plants, which can adversely affect crop growth and productivity. The biological effects of ABA are dependent on its concentration and signal transduction pathways. However, due to its susceptibility to the environment, it is essential to find a suitable biotechnological approach to coat ABA for its application. One promising approach is to utilize alginate and chitosan, two natural polysaccharides known for their strong affinity for water and their ability to act as coating agents. In this study, an alginate-chitosan blend was employed to develop an ABA cover. To achieve this, an alginate-chitosan-abscisic acid (ALG-CS-ABA) blend was prepared by forming ionic bonds or complexes with calcium ions, or through dual cross-linking. This was done by dripping a homogeneous solution of alginate-chitosan and ABA into a calcium chloride solution, resulting in the formation of the blend. By combining the unique properties of alginate, chitosan, and ABA, the resulting ALG-CS-ABA blend can potentially offer enhanced stability, controlled release, and improved protection of ABA. These characteristics make it a promising biotechnological approach for various applications, including the targeted delivery of ABA in agricultural practices or in the development of innovative plant-based products. Further evaluation and characterization of the ALG-CS-ABA blend will provide valuable insights into its potential applications in the fields of biomedicine, agriculture, and tissue engineering.

Thermoplastic starch/bentonite clay nanocomposite reinforced with vitamin B2: Physicochemical characteristics and release behavior

This study presents the development and characterization of a nanocomposite material, consisting of thermoplastic starch (TPS) reinforced with bentonite clay (BC) and encapsulated with vitamin B₂ (VB). The research is motivated by the potential of TPS as a renewable and biodegradable substitute for petroleum-based materials in the biopolymer industry. The effects of VB on the physicochemical properties of TPS/BC films, including mechanical and thermal properties, water uptake, and weight loss in water, were investigated. In addition, the surface morphology and chemical composition of the TPS samples were analyzed using high-resolution SEM microscopy and EDS, providing insight into the structure-property relationship of the nanocomposites. The results showed that the addition of VB significantly increased the tensile strength and Young's modulus of TPS/BC films, with the highest values observed for nanocomposites containing 5 php of VB and 3 php of BC. Furthermore, the release of VB was controlled by the BC content, with higher BC content leading to lower VB release. These findings demonstrate the potential of TPS/BC/VB nanocomposites as environmentally friendly materials with improved mechanical properties and controlled release of VB, which can have significant applications in the biopolymer industry.

In Vitro Digestibility of Minerals and B Group Vitamins from Different Brewers' Spent Grains

Brewers' spent grain (BSG), the main by-product of the brewing industry, is a rich source of minerals and water-soluble vitamins such as thiamine, pyridoxine, niacin, and cobalamin. Bioaccessibility through in vitro digestion is an important step toward the complete absorption of minerals and B group vitamins in the gastrointestinal system. Inductively coupled plasma optical emission spectrometry (ICP-OES) together with inductively coupled plasma quadrupole mass spectrometry (ICP-MS) was used for the quantification of the macro- and micro-minerals. An ultra-high performance liquid chromatography (UHPLC) system coupled with a diode array detector (DAD) was used for B group vitamin identification. Four different industrial BSG samples were used in the present study, with different percentages of malted cereals such as barley, wheat, and degermed corn. Calcium's bioaccessibility was higher in the BSG4 sample composed of 50% malted barley and 50% malted wheat (16.03%), while iron presented the highest bioaccessibility value in the BSG2 sample (30.03%) composed of 65% Pale Ale malt and 35% Vienna malt. On the other hand, vitamin B1 had the highest bioaccessibility value (72.45%) in the BSG3 sample, whilst B6 registered the lowest bioaccessibility value (16.47%) in the BSG2 sample. Therefore, measuring the bioaccessibilty of bioactive BSG compounds before their further use is crucial in assessing their bioavailability.