Encapsulation Methodologies Research Articles

A comprehensive review of the characterization, host interactions, and stabilization advancements on probiotics: Addressing the challenges in functional food diversification.

The demand for functional food is rising in tandem with the prevalence of chronic diseases. Probiotics play a crucial role in functional food development, yet their ability to confer health benefits to the host remains a topic of debate according to Food and Agriculture Organization/World Health Organization requirements. The application of culturomics, innovative isolation techniques, within the realm of probiotics is increasingly deemed essential for fully harnessing the latent potential of microbial reservoirs. Nevertheless, its application remains confined predominantly to human fecal sources. Following the integration of probiogenomics, significant advancements have been made in the safety assessment of probiotics. However, the adoption of novel probiotic microorganisms has yet to match the requisite pace. Progress in research concerning host-probiotic interactions by employing omics technologies, particularly in animal models, is notable. Nonetheless, the comprehensive elucidation of mechanisms of action and human trial studies are lagging behind. Additionally, the viability of probiotics, spanning from their production as functional foods to their transit to the human colon, has markedly improved through encapsulation techniques. Nevertheless, opportunities for exploration persist regarding alternative coating materials and diverse encapsulation methodologies. Furthermore, there is a discernible transition in the domain of probiotic-based functional foods, shifting away from a primarily dairy-centric focus toward inclusion in a broader array of food categories. This comprehensive review addresses critical issues ranging from isolation sources and novel techniques to the final functional food developments. while doing so, it explores probiogenomics applications for probiotic characterization, investigations into host-probiotic interactions, and strategies for probiotic stabilization under harsh environmental conditions.

Synthesis and evaluation of Maillard conjugates for encapsulation and controlled delivery of quercetin under simulated gastrointestinal tract conditions

AbstractEncapsulation of bioactive molecules for therapeutic use is gaining great interest in the scientific community. Several encapsulation methodologies have been evaluated, sacrificing, in some cases, either encapsulation efficiency or compound integrity. Our work developed Maillard conjugates (MCs) based on the whey protein (WP)‐Maltodextrin (MD) interaction to encapsulate quercetin by freeze‐drying. The WP:MD ratio used (1:2 or 1:3) yielded the formation of MCs, demonstrated by an increased browning index and changes in the protein secondary structure. Freeze‐drying showed high encapsulation efficiency, reaching 87.65% and 84.72% in treatments loaded with 3.3 mg quercetin/g MCs. Quercetin‐loaded MCs showed spherical‐shape (4–10 μm) and a negative charge, suggesting colloidal stability. Moreover, in vitro tests demonstrated a sustained release of quercetin throughout the oral, gastric, and intestinal phases, highlighting the MCs efficacy as bioactive delivery systems. This work provides useful information to design bioactive compound delivery systems for food and pharmaceutical applications.

Exploring the impact of encapsulation on the stability and bioactivity of peptides extracted from botanical sources: trends and opportunities.

Bioactive peptides derived from plant sources have gained significant attention for their potential use in preventing and treating chronic degenerative diseases. However, the efficacy of these peptides depends on their bioaccessibility, bioavailability, and stability. Encapsulation is a promising strategy for improving the therapeutic use of these compounds. It enhances their stability, prolongs their shelf life, protects them from degradation during digestion, and enables better release control by improving their bioaccessibility and bioavailability. This review aims to analyze the impact of various factors related to peptide encapsulation on their stability and release to enhance their biological activity. To achieve this, it is necessary to determine the composition and physicochemical properties of the capsule, which are influenced by the wall materials, encapsulation technique, and operating conditions. Furthermore, for peptide encapsulation, their charge, size, and hydrophobicity must be considered. Recent research has focused on the advancement of novel encapsulation methodologies that permit the formation of uniform capsules in terms of size and shape. In addition, it explores novel wall materials, including polysaccharides derived from unconventional sources, that allow the precise regulation of the rate at which peptides are released into the intestine.

Microfluidic Strategies for Encapsulation, Protection, and Controlled Delivery of Probiotics.

Probiotics are indispensable for maintaining the structure of gut microbiota and promoting human health, yet their survivability is frequently compromised by environmental stressors such as temperature fluctuations, pH variations, and mechanical agitation. In response to these challenges, microfluidic technology emerges as a promising avenue. This comprehensive review delves into the utilization of microfluidic technology for the encapsulation and delivery of probiotics within the gastrointestinal tract, with a focus on mitigating obstacles associated with probiotic viability. Initially, it elucidates the design and application of microfluidic devices, providing a precise platform for probiotic encapsulation. Moreover, it scrutinizes the utilization of carriers fabricated through microfluidic devices, including emulsions, microspheres, gels, and nanofibers, with the intent of bolstering probiotic stability. Subsequently, the review assesses the efficacy of encapsulation methodologies through in vitro gastrointestinal simulations and in vivo experimentation, underscoring the potential of microfluidic technology in amplifying probiotic delivery efficiency and health outcomes. In sum, microfluidic technology represents a pioneering approach to probiotic stabilization, offering avenues to cater to consumer preferences for a diverse array of functional food options.

Chemical Stability of Metal Halide Perovskite Detectors

Metal halide perovskite (MHP) detectors are highly esteemed for their outstanding photoelectric properties and versatility in applications. However, they are unfortunately prone to degradation, which constitutes a significant barrier to their sustained performance. This review meticulously delves into the causes leading to their instability, predominantly attributable to factors such as humidity, temperature, and electric fields and, notably, to various radiation factors such as X-rays, γ-rays, electron beams, and proton beams. Furthermore, it outlines recent advancements in strategies aimed at mitigating these detrimental effects, emphasizing breakthroughs in composition engineering, heterostructure construction, and encapsulation methodologies. At last, this review underscores the needs for future improvements in theoretical studies, material design, and standard testing protocols. In the pursuit of optimizing the chemical stability of MHP detectors, collaborative efforts are in an imperative need. In this way, broad industrial applications of MHP detectors could be achieved.

Nano/microformulations for Bacteriophage Delivery.

Encapsulation methodologies allow the protection of bacteriophages for overcoming critical environmental conditions. Moreover, they improve the stability and the controlled delivery of bacteriophages which is of great innovative value in bacteriophage therapy. Here, two different encapsulation methodologies of bacteriophages are described using two biocompatible materials: a lipid cationic mixture and a combination of alginate with the antacid CaCO3. To perform bacteriophage encapsulation is necessary to dispose of a purified and highly concentrated lysate (around 1010 to 1011 pfu/mL) and a specific equipment. Both methodologies have been successfully applied for encapsulating Salmonella bacteriophages with different morphologies. Also, the material employed does not modify the antibacterial action of bacteriophages. Moreover, both technologies can be adapted to any bacteriophage and possibly to any delivery route for bacteriophage therapy.

Biofunctionalized Nanomaterials: Alternative for Encapsulation Process Enhancement

In recent years, interest in the development of nanometric materials with specific characteristics has grown; however, there are few scientific contributions that associate encapsulation methodologies and matrices with the particle objective (metabolic directions, type of administration, biological impact, and biocompatibility). This review focuses on describing the benefits and disadvantages of different techniques for designing custom particles and alternatives for the biofunctionalization nanomaterials regarding the biological impact of a nanomaterial with potential use in foods known as nutraceuticals. The study of optical properties, physicochemical factors, and characteristics such as rheological can predict its stability in the application matrix; however, not only should the characterization of a nanocomposite with applications in food be considered, but also the biological impact that it may present.

Drug Delivery: Hydrophobic DrugEncapsulation into Amphiphilic Block CopolymerMicelles.

Drug encapsulation into amphiphilic block copolymer micelles aims to increase drug solubility and minimize drug degradation upon administration, avoid undesirable side effects and ameliorate drug bioavailability. Drug encapsulation methodologies including thin-film hydration method and organic cosolvent method are described in this chapter. Often, it is desirable to determine the most efficient solubilization protocol leading to functional drug delivery nanovehicles in each case. The encapsulation of curcumin into PEO-b-PPO-b-PEO (Pluronic F-127) polymeric micelles through thin-film hydration method presents the most promising results. Indomethacin can be loaded successfully into the hydrophobic cores of PEO-b-PCL amphiphilic block copolymer micelles following both encapsulation protocols.

The Entrapment of Somatostatin in a Lipid Formulation: Retarded Release and Free Radical Reactivity.

The natural peptide somatostatin has hormonal and cytostatic effects exerted by the binding to specific receptors in various tissues. Therapeutic uses are strongly prevented by its very short biological half-life of 1–2 min due to enzymatic hydrolysis, therefore encapsulation methodologies are explored to overcome the need for continuous infusion regimes. Multilamellar liposomes made of natural phosphatidylcholine were used for the incorporation of a mixture of somatostatin and sorbitol dissolved in citrate buffer at pH = 5. Lyophilization and reconstitution of the suspension were carried out, showing the flexibility of this preparation. Full characterization of this suspension was obtained as particle size, encapsulation efficiency and retarded release properties in aqueous medium and human plasma. Liposomal somatostatin incubated at 37 °C in the presence of Fe(II) and (III) salts were used as a biomimetic model of drug-cell membrane interaction, evidencing the free radical processes of peroxidation and isomerization that transform the unsaturated fatty acid moieties of the lipid vesicles. This study offers new insights into a liposomal delivery system and highlights molecular reactivity of sulfur-containing drugs with its carrier or biological membranes for pharmacological applications.

Micro- and nano-encapsulation in food industry

Encapsulation can be defined as a process of entrapping one substance within another substance producing particles with diameters of a few nm to a few mm. The entrapped material is usually a liquid, but may be a solid or a gas. The main reason of using encapsulation is the fact that some nutrients do not remain in the food for a significant amount of time or may react with the other food components causing undesirable effects. It is possible to use micro- and nanoencapsulation techniques. The first one, microencapsulation, is a technology that can improve the retention time of the nutrient in the food and allow controlled release at specific times, during food consumption or in the intestinal gut (microencapsulation of vitamin). Nanoencapsulation has the potential to protect sensitive bioactive food ingredients from unfavourable environmental conditions, enhance solubilisation, improve taste and odour masking, and enhance bioavailability of poorly absorbable function ingredients. In this review, some relevant aspects of encapsulation methodologies, coating materials and their uses in food technology were discussed.

Isorhamnetin encapsulation into biogenic silica from Cyclotella sp. using a microfluidic device for drug delivery applications

Abstract Diatoms have the peculiarity to synthesize amorphous silica around the cell wall. Frustules (empty silica shells) have the advantages of being biocompatible, biodegradable, nontoxic and rich with hydroxyl groups on the surface. Frustules have been used in diverse fields, but recently their application in the biomedical field has been investigated. Drug delivery systems (DDS) have been studied to improve the therapeutic effect of different drugs, especially hydrophobic drugs. Different encapsulation methodologies have been used to load the drug in a carrier such as drop-wise methodology or solvent evaporation. However, a reproducible methodology that reduces handling error must be explored. Herein, a novel technique ESCARGOT (Embedded SCAffold RemovinG Open Technology) was used to fabricate the microfluidic device and exploited as a novel tool to encapsulate hydrophobic drugs into the in-house developed biogenic silica from Cyclotella sp. Isorhamnetin was used as a model drug with hydrophobic in nature. Three different concentrations were studied: 20, 60 and 100 μg/mL, and three different resident times in the device (0.4, 1 and 2 min). The highest encapsulation efficiency (EE%) and loading capacity (LC%) were 17.92% and 1.63% respectively. According to the statistical analysis, the optimum conditions to obtain a maximum EE% were 2 min and 20 μg/mL. The isorhamnetin release behavior was observed with a burst release in the first hour with 48.26%, while the total amount of drug was delivered in 3 h. The feasibility of frustules as carriers and the microfluidic device as a mixer was successfully accessed. This methodology could be used as a standardization technique to obtain reproducible results.

Developments in encapsulation of insulin: Is oral delivery now possible?

This review presents the possibilities of oral delivery of insulin. Insulin, being readily destroyed/ transformed by the proteolytic enzymes and first-pass effects in the digestive system, has mainly been administered through injection, such as intravenous injection and transdermal injection. With developments in the material sciences, appropriate encapsulation methodologies have been developed that could be employed to protect insulin from the digestive effects of the human GI system, and thereby have opened a gateway of research exploring the oral route of insulin delivery. One approach is to incorporate insulin into an emulsion with an appropriate oil-phase, which protects the insulin from degradation. Coating with natural or synthetic polymeric materials, or with lipids, followed by size-reduction to 100-1000 nm is applied as another common approaches of insulin encapsulation. Other approaches like liposomes, nanogels, etc. are also being explored. This review gives a summary of methods of preparation as well as in vitro and in vivo bioavailability of insulin through these methods. It is observed that the oral bioavailability of insulin intake has increased from about 0.1% to about 20% for encapsulated insulin.

Use of Electrosprayed Agave Fructans as Nanoencapsulating Hydrocolloids for Bioactives.

High degree of polymerization Agave fructans (HDPAF) are presented as a novel encapsulating material. Electrospraying coating (EC) was selected as the encapsulation technique and β-carotene as the model bioactive compound. For direct electrospraying, two encapsulation methodologies (solution and emulsion) were proposed to find the formulation which provided a suitable particle morphology and an adequate concentration of β-carotene encapsulated in the particles to provide a protective effect of β-carotene by the nanocapsules. Scanning electron microscopy (SEM) images showed spherical particles with sizes ranging from 440 nm to 880 nm depending on the concentration of HDPAF and processing parameters. FTIR analysis confirmed the interaction and encapsulation of β-carotene with HDPAF. The thermal stability of β-carotene encapsulated in HDPAF was evidenced by thermogravimetric analysis (TGA). The study showed that β-carotene encapsulated in HDPAF by the EC method remained stable for up to 50 h of exposure to ultraviolet (UV) light. Therefore, HDPAF is a viable option to formulate nanocapsules as a new encapsulating material. In addition, EC allowed for increases in the ratio of β-carotene:polymer, as well as its photostability.

Nano/Micro Formulations for Bacteriophage Delivery.

Encapsulation methodologies allow the protection of bacteriophages for overcoming critical environmental conditions. Moreover, they improve the stability and the controlled delivery of bacteriophages which is of great innovative value in bacteriophage therapy. Here, two different encapsulation methodologies of bacteriophages are described using two biocompatible materials: a lipid cationic mixture and a combination of alginate with the antacid CaCO3. To perform bacteriophage encapsulation, a purified lysate highly concentrated (around 1010-1011pfu/mL) is necessary, and to dispose of a specific equipment. Both methodologies have been successfully applied for encapsulating Salmonella bacteriophages with different morphologies. Also, the material employed does not modify the antibacterial action of bacteriophages. Moreover, both technologies can also be adapted to any bacteriophage and possibly to any delivery route for bacteriophage therapy.

Type 1 Diabetes Prevention: A Goal Dependent on Accepting a Diagnosis of an Asymptomatic Disease.

Type 1 diabetes, a disease defined by absolute insulin deficiency, is considered a chronic autoimmune disorder resulting from the destruction of insulin-producing pancreatic β-cells. The incidence of childhood-onset type 1 diabetes has been increasing at a rate of 3%–5% per year globally. Despite the introduction of an impressive array of therapies aimed at improving disease management, no means for a practical “cure” exist. This said, hope remains high that any of a number of emerging technologies (e.g., continuous glucose monitoring, insulin pumps, smart algorithms), alongside advances in stem cell biology, cell encapsulation methodologies, and immunotherapy, will eventually impact the lives of those with recently diagnosed or established type 1 diabetes. However, efforts aimed at reversing insulin dependence do not address the obvious benefits of disease prevention. Hence, key “stretch goals” for type 1 diabetes research include identifying improved and increasingly practical means for diagnosing the disease at earlier stages in its natural history (i.e., early, presymptomatic diagnosis), undertaking such efforts in the population at large to optimally identify those with presymptomatic type 1 diabetes, and introducing safe and effective therapeutic options for prevention.

Probiotics production and alternative encapsulation methodologies to improve their viabilities under adverse environmental conditions

Probiotic products are dietary supplements containing live microorganisms producing beneficial health effects on the host by improving intestinal balance and nutrient absorption. Among probiotic microorganisms, those classified as lactic acid bacteria are of major importance to the food and feed industries. Probiotic cells can be produced using alternative carbon and nitrogen sources, such as agroindustrial residues, at the same time contributing to reduce process costs. On the other hand, the survival of probiotic cells in formulated food products, as well as in the host gut, is an essential nutritional aspect concerning health benefits. Therefore, several cell microencapsulation techniques have been investigated as a way to improve cell viability and survival under adverse environmental conditions, such as the gastrointestinal milieu of hosts. In this review, different aspects of probiotic cells and technologies of their related products are discussed, including formulation of culture media, and aspects of cell microencapsulation techniques required to improve their survival in the host.

Comparison of the Acidity of Heteropolyacids Encapsulated in or Impregnated on SBA-15

Heteropolyacids (HPA) immobilized onto SBA-15 silica were prepared by two different ways using either impregnation or encapsulation methodologies. Two Keggin-type HPA, H3PW12O40 and H4SiW12O40 were considered in this study. The resulting hybrid materials were fully characterized by N2 adsorption-desorption isotherms, XRD, FT-IR, Raman, diffuse reflectance UV-Vis spectroscopies and 31P MAS NMR. All characterization methods showed that at room temperature the catalysts contained well-dispersed and intact Keggin units throughout the solid. The catalytic activity of these solids was investigated in the isomerization of n-hexane. The impregnated and encapsulated phosphotungstic catalysts performed similarly in catalysis showing that the amount of active sites was nearly the same in both catalysts. On the contrary, the tungstosilicic encapsulated material was completely inactive while its impregnated counterpart was even more active than the phosphotungstic derived catalysts. The acidity of the solids was measured by various methods: microcalorimetry of ammonia adsorption, ammonia desorption followed by Temperature Programmed Desorption (TPD) and DRIFT/GC-MS and pyridine adsorption followed by infrared spectroscopy. Only pyridine adsorption and ammonia desorption followed by DRIFT/GC-MS agreed with the catalytic data. Ammonia adsorption followed by microcalorimetry was not able to differentiate between the four catalysts while the TPD experiments led to unreliable results, as not only the evolved ammonia but also other molecules such as water were taken into account in the measurements. The behavior difference between the encapsulated silico- and phosphotungstic acids was explained by a more pronounced encapsulation in the case of silicon.

English

Encapsulation technologies are used to keep probiotic cell viable throughout storage, commercialization and use in food products, so that these cells are active during their passage through the gastrointestinal tract. This review describes the most common encapsulation technologies and encapsulation materials used for maintaining the viability of probiotic bacteria under adverse external conditions. Illustrations are presented to facilitate the understanding of the various encapsulation methodologies. Supercritical fluid technologies for encapsulation as well as new wall materials are discussed. It is concluded that several variables affect the viability of encapsulated probiotic cells and therefore optimization tools including response, genetic algorithms, quadratic sequential programming are needed for appropriate material selection.   Key words: Lactic acid bacteria, lyophilization, spray drying, extrusion, cellular viability.

Encapsulation of actives for sustained release

Encapsulation of actives in miniature reservoirs, called microcapsules, is used for protection and in particular controlled release of the active. Regarding controlled release applications, the most common function of the microcapsule is to sustain or extend the release of the active. A number of encapsulation methodologies are available including; internal phase separation, interfacial polymerization, formation of multiple emulsions, Layer-by-Layer adsorption of polyelectrolytes and soft templating techniques, all of which are reviewed in this Perspective. The choice of method depends on the nature of the active (hydrophilic/hydrophobic, size, physical state) and on the intended release rate and release profile. Ways to manipulate the release of the active by tailoring the physicochemical properties of the microcapsule are reviewed. Moreover, appropriate diffusion models are introduced to describe the release profile from a variety of microcapsule morphologies, including Fickian diffusion models and Brownian motion, and the meaning and the misuse of the term "zero-order release" are briefly discussed.

Formulating the alginate–polyornithine biocapsule for prolonged stability: Evaluation of composition and manufacturing technique

Alginate encapsulation is one of the most widely used techniques for introducing cell-based therapeutics into the body. Numerous encapsulation methodologies exist, utilizing a variety of alginates, purification technologies, and unique polycationic membrane components. The stability of a conventional alginate formulation encapsulated using a commercially available technique and apparatus has been characterized extensively. The current study employs an encapsulation protocol and ultra-pure alginate pioneered at the University of Perugia. The enhanced microcapsules were produced, characterized, and implanted into the brain, peritoneal cavity, and subcutaneous space of Long-Evans rats. After 14, 28, 60, 90, 120, and 180 or 215 days, capsules were explanted and the surface was analyzed using Fourier-transform infrared spectroscopy (FTIR) and scanning electron microscopy (SEM). Image analysis was carried out to measure changes in diameter and wall thickness. FTIR peak analysis and surface morphology from SEM indicated that the enhanced encapsulation technique and formulation produced a stable biocapsule capable of survival in all sites, including the harsh peritoneal environment, for at least 215 days. Preimplant analysis showed a marked increase in the structural integrity of the enhanced formulation with improved elasticity and burst strength compared with the baseline formulation, which remained stable for less than 60 days. The enhanced microcapsule composition showed advantages in physical strength and longevity, indicating that small changes in encapsulation methodologies and materials selection can dramatically impact the stability and longevity of alginate microcapsules and their contents.