Extending Viability of Bifidobacterium longum in Chitosan-Coated Alginate Microcapsules Using Emulsification and Internal Gelation Encapsulation Technology

Influence of the addition of gum arabic and xanthan gum in the preparation of sodium alginate microcapsules coated with chitosan hydrochloride on the survival of Lacticaseibacillus rhamnosus GG

The microencapsulation of Lactocaseibacillus rhamnosus GG in a matrix of sodium alginate, xanthan gum, gum arabic and chitosan hydrochloride is a promising strategy for protecting this probiotic during passage through the gastrointestinal tract. This study evaluated the influence on the viability of Lactocaseibacillus rhamnosus GG encapsulated with these polymers by external ionic gelation with vibratory extrusion and the microcapsules that showed the best results of capsulation efficiency, viability, size and morphology were analyzed by Fourier transform infrared spectroscopy (FTIR), thermal analysis (TGA) and exposure to environmental stress conditions and gastrointestinal simulation. The result revealed encapsulation efficiency values above 95 % for all formulations and survival rate higher than 6 log CFU/mL for most analyzed groups. The lowest viability values after storage at 7 °C were presented by formulations prepared with Arabic Gum and Xanthan, as well as the largest sizes, expansion index, and physical integrity loss of the microcapsules. Sodium alginate microcapsules coated with chitosan hydrochloride demonstrated enhanced viability during storage at 7 °C and 25 °C, alongside superior cell survival rates under environmental stress conditions and simulated gastrointestinal environments indicating that sodium alginate-chitosan hydrochloride microparticles are expected to become an ideal carrier for the actives encapsulation in pharmaceutical and food and industries.

Advances in prebiotic carbohydrate-based targeted delivery: Overcoming gastrointestinal challenges for bioactive ingredients

Natural bioactive ingredients face challenges in extensive application owing to low oral bioavailability. This can be improved by overcoming gastrointestinal barriers and facilitating targeted release through delivery strategies. This study provides a comprehensive review of targeted delivery systems using prebiotic carbohydrate matrices, focusing on structures, release mechanisms and applications. The bioactive ingredients can be encapsulated into nanohydrogels, nanoparticles, nanoemulsions, micro/nanocapsules and nanofibres to achieve controlled/targeted delivery to predetermined locations via interactions with pH, mucus, microbiome, enzymes and other factors in the colon. In particular, the prebiotic function of carbohydrates is generated by colonic microbiota degradation and fermentation, producing beneficial postbiotics through multiple metabolic pathways. This study provides certain insights into the in-depth development and application of prebiotic carbohydrate-based targeted delivery systems in the fields of food and health.

Enhanced Thermal and Storage Stability of Glucose Oxidase via Encapsulation in Chitosan-Coated Alginate and Carboxymethyl Cellulose Gel Particles

Glucose oxidase (GOD) is widely used as an important oxidoreductase in various fields. However, maintaining the vitality and stability of GOD under environmental stress is a challenge. To improve the thermal and storage stability of GOD, this study constructed sodium alginate-carboxymethyl cellulose sodium gel particles (SA/CMC) and chitosan-coated SA/CMC gel particles (CS/SA/CMC) of GOD. The encapsulation efficiency (EE), gel particle structure, stability, and release behavior of GOD were evaluated. The results showed that the thermal stability of GOD encapsulated in SA/CMC and CS/SA/CMC gel particles was improved by approximately 2.8-fold and 4.3-fold compared with the free enzyme at 85 °C, respectively. In addition, CS/SA/CMC gel particles enhanced the enzyme activity retention rate of GOD to over 80% during storage at 4 °C for four weeks. Both SA/CMC and CS/SA/CMC gel particles loaded with GOD had more than 70% of the enzymes released during the simulated gastrointestinal experiment. The results demonstrated that encapsulating GOD in SA/CMC and CS/SA/CMC gel particles could improve its thermal stability and storage stability, which is conducive to further expanding the application of GOD in food, pharmaceutical and feed industries.

Improving the physical stability of Lactobacillus plantarum LP90 during storage by mixing carboxymethylated dextran-whey protein conjugates and small-molecule sugars

To explore the effect of small-molecule sugars on the physical stability of microcapsules and enhance probiotic preservation, carboxymethylated dextran and whey protein conjugate (WP-CD5d) by Maillard reaction were used as the wall material. Trehalose, lactose, and sucrose were used as lyoprotectants to encapsulate Lactobacillus plantarum LP90 (LP90) during storage, forming microcapsules labeled as WP-CD5dH, WP-CD5dR, and WP-CD5dZ, respectively. WP-CD5dH and WP-CD5dR exhibited the highest viability after freeze-drying, with survival rates of 97.8 % ± 0.9 % and 98.5 % ± 0.5 % respectively. LP90 microcapsules exhibited strong resistance to simulated gastrointestinal fluid over 5 h. The Guggenheim-Anderson-de Boer (GAB) and Gordon-Taylor model showed that WP-CD5dH had the best reduction in water plasticization (k was 4.0). 1H NMR spectra confirmed that WP-CD5dH exhibited the lowest molecular mobility. Furthermore, the storage experiment showed that WP-CD5dH provided the best protection for LP90 at 11 % RH, with a K value of 0.021. These results suggest that the probiotic mechanism of small-molecule sugars involves forming intermolecular forces with WP-CD5d, which helps to maintain the glassy state.

Probiotics Encapsulated via Biological Macromolecule for Neurological Therapy and Functional Food: A Review

Probiotics are live microorganisms that confer health benefits to humans, offering significant potential for preventing and treating various diseases. Neurological disorders, driven by multifaceted factors and linked to high disability rates, have become a growing global concern, particularly in the context of an aging population. Recent studies emphasize a strong connection between dysbiosis of the gut microbiota and neurological disorders. Probiotics have emerged as promising therapeutic interventions due to their ability to modulate the gut microbiota and influence the production of key metabolites, such as short-chain fatty acids and neurotransmitters, crucial for neurological health. However, probiotic viability is often compromised, limiting their therapeutic efficacy. We propose that developing high-activity probiotic formulations, coupled with innovative delivery strategies, holds considerable promise for advancing neurological treatments. Encapsulation systems have proven effective in enhancing probiotic stability and efficacy. This review discusses advances in probiotic delivery using biological macromolecule-based encapsulation, addressing key challenges in maintaining viability during production, storage, and digestion. It also highlights emerging delivery systems, such as microencapsulation, aimed at improving stability and therapeutic effectiveness. Additionally, the review explores the potential of functional foods enriched with probiotics for neurological health. Future research should explore clinical applications of encapsulated probiotics and support the development of functional foods to enhance neurological health.

Lactiplantibacillus plantarum encapsulated by chitosan-alginate and soy protein isolate-reducing sugars conjugate for enhanced viability

To investigate the protective effects of various wall materials on probiotics, two types of Lactiplantibacillus plantarum 90 (Lp90) microcapsules were prepared using sodium alginate and chitosan (Lp-AC), soy protein isolate (SPI) and reducing sugars conjugate (Lp -MRP) as wall materials, respectively. The physical properties, cell viability under different conditions and the application of the microcapsules were investigated. Results showed that the selected wall materials were safe to Lp90 and their simulated digestion products exhibited antioxidant activities and prebiotic properties. The encapsulation efficiencies of Lp-AC and Lp-MRP were above 80 %. Both microcapsules significantly enhanced cell survival rates under various conditions including low pH, bile salts, thermal processing, mechanical force, storage, and gastrointestinal digestion, with Lp-MRP demonstrating superior protective effects. When incorporated into milk and orange juice and stored at 4 °C for 28 d, the colony counts of beverages containing Lp90 microcapsules exceeded 6 Log CFU/mL, with minimal changes in total soluble solids. Lp-MRP exhibited higher cell viability and smaller viscosity changes at 25 °C for 28 d. Therefore, the single-layer encapsulation using SPI and reducing sugars conjugate showed promise over traditional chitosan-alginate double-layer encapsulation concerning probiotic protection, targeted delivery, and application.

Lactiplantibacillus plantarum 299V fermented in microcapsules shows enhanced stability and could improve the microbial quality and safety of oysters through bioaccumulation

In this study, microcapsules of Lactiplantibacillus plantarum 299V were prepared using an emulsification/internal gelation technique. Loads of the probiotics were condensed to 9.86 ± 0.13 log CFU/g after 24 h fermentation of the microcapsules. Physical characterization revealed that L. plantarum 299V cells were uniformly distributed within the core of the microcapsules, with a mean diameter of 109.81 ± 0.39 µm and a span value of 0.36 ± 0.00, which were comparable to those of the unfermented microcapsules (p > 0.05). The viability of L. plantarum 299V in the fermented microcapsules was 2.08 ± 0.15 log higher than that of free cells at the end of 5 h simulated gastrointestinal digestion (p < 0.05). Oysters were able to accumulate the fermented microcapsules through filter feeding, resulting in a load of probiotics exceeding 6.00 log CFU/g. The presence of L. plantarum 299V-carrying microcapsules in oyster tissues significantly suppressed spoilage-causing bacteria during 11 days refrigeration storage, suggested by the tested parameters, including total psychrotrophic bacteria, H2S-producing bacteria, and Pseudomonas spp. (p < 0.05). Pathogenic bacteria, including Vibrio parahaemolyticus and Salmonella enterica artificially introduced into oysters, were also significantly suppressed by over 1.00-log within 4 days compared to control samples (p < 0.05). In summary, oysters bioaccumulated with fermented L. plantarum 299V-carrying microcapsules, justified a novel probiotic-carrying product to exsert the health-promoting effect of probiotics. This solution could also enhance the microbial quality and safety of oysters during storage.

Impact of Bifidobacterium longum Subspecies infantis on Pediatric Gut Health and Nutrition: Current Evidence and Future Directions

Background: the intestinal microbiota, a complex community vital to human health, is shaped by microbial competition and host-driven selective pressures. Among these microbes, Bifidobacterium plays a crucial role in early gut colonization during neonatal stages, where Bifidobacterium longum subspecies infantis (B. infantis) predominates and is particularly prevalent in healthy breastfed infants. Objectives: as we embark on a new era in nutrition of the pediatric population, this study seeks to examine the existing understanding regarding B. infantis, encompassing both preclinical insights and clinical evidence. Methods: through a narrative disceptation of the current literature, we focus on its genetic capacity to break down various substances that support its survival and dominance in the intestine. Results: using "omics" technologies, researchers have identified beneficial mechanisms of B. infantis, including the production of short-chain fatty acids, serine protease inhibitors, and polysaccharides. While B. infantis declines with age and in various diseases, it remains a widely used probiotic with documented benefits for infant and child health in numerous studies. Conclusions: the current scientific evidence underscores the importance for ongoing research and clinical trials for a deeper understanding of B. infantis's role in promoting long-term health.

Exploring Calcium Alginate-Based Gels for Encapsulation of Lacticaseibacillus paracasei to Enhance Stability in Functional Breadmaking

This study focuses on evaluating the efficiency of acid-tolerant Lacticaseibacillus paracasei bacteria encapsulated in an alginate-based gel matrix during repeated sourdough fermentation cycles, as well as their preservation during storage and throughout baking at high temperature. A double-coating procedure was applied, involving the encapsulation of bacterial cells in calcium alginate, which was further coated with chitosan. The encapsulation efficiency (EE) did not show significant difference between alginate and alginate-chitosan (97.97 and 96.71%, respectively). The higher number of L. paracasei bacteria was preserved in double-coated microbeads, with survivability rates of 89.51% and 96.90% in wet and dried microbeads, respectively. Encapsulated bacteria demonstrated effective fermentation ability, while double gel-coated cells exhibited slower acidification during sourdough fermentation, maintaining higher efficiency in the second fermentation cycle. The addition of freeze-dried, alginate-based gel-encapsulated bacteria (2-4%, w/w flour) significantly (p < 0.05) improved bread quality and extended its shelf life. A double-layer coating (alginate-chitosan) can be introduced as an innovative strategy for regulating the release of lactic acid bacteria and optimizing fermentation processes. Powdered alginate or alginate-chitosan gel-based L. paracasei microcapsules, at appropriate concentrations, can be used in the production of baked goods with acceptable quality and sensory properties, achieving a lactic acid bacteria count of approximately 106 CFU/g in the crumb, thereby meeting the standard criteria for probiotic bakery products.

Preparation of a Lactobacillus rhamnosus ATCC 7469 microencapsulated-lactulose synbiotic and its effect on equol production

Equol is a highly active product of soy isoflavones produced by specific bacteria in the human or animal colon. However, equol production is influenced by differences in the gut flora carried by the body. Our previous research has shown that a synbiotic preparation comprising the probiotic Lactobacillus rhamnosus ATCC 7469 and the prebiotic lactulose can enhance equol production by modulating the intestinal flora. Nevertheless, the harsh environment of the gastrointestinal tract limits this capability by diminishing the number of probiotics reaching the colon. Microencapsulation of probiotics is an effective strategy to enhance their viability. In this study, probiotic gel microspheres (SA-S-CS) were prepared using an extrusion method, with sodium alginate (SA) and chitosan (CS) serving as the encapsulating materials. Scanning electron microscopy (SEM) was employed to observe the surface morphology and the internal distribution of bacteria within the microcapsules. The structural characteristics of the microcapsules were investigated using Fourier-transform infrared spectroscopy (FTIR) and X-ray diffraction (XRD). Furthermore, the thermal stability, storage stability, probiotic viability post-simulated gastrointestinal fluid treatment, and colon release rate were examined. Finally, the impact of probiotic microencapsulation on promoting equol production by the synbiotic preparation was assessed. The results indicated that the microcapsules exhibited a spherical structure with bacteria evenly distributed on the inner surface. Studies on thermal and storage stability showed that the number of viable cells in the probiotic microcapsule group significantly increased compared to the free probiotic group. Gastrointestinal tolerance studies revealed that after in vitro simulated gastrointestinal digestion, the amount of viable cells in the microcapsules was 7 log10 CFU g-1, demonstrating good gastrointestinal tolerance. Moreover, after incubation in simulated colonic fluid for 150 min, the release rate of probiotics reached 93.13%. This suggests that chitosan-coated sodium alginate microcapsules can shield Lactobacillus rhamnosus ATCC 7469 from the gastrointestinal environment, offering a novel model for synbiotic preparation to enhance equol production.

A comprehensive review of Bifidobacterium spp: as a probiotic, application in the food and therapeutic, and forthcoming trends

Recently, more consumers are interested in purchasing probiotic food and beverage products that may improve their immune health. The market for functional foods and beverages that include Bifidobacterium is expanding because of their potential uses in both food and therapeutic applications. However, maintaining Bifidobacterium's viability during food processing and storage remains a challenge. Microencapsulation technique has been explored to improve the viability of Bifidobacterium. Despite the technical, microbiological, and economic challenges, the market potential for immune-supporting functional foods and beverages is significant. Additionally, there is a shift toward postbiotics as a solution for product innovation, a promising postbiotic product that can be incorporated into various food and beverage formats is also introduced in this review. As consumers become more health-conscious, future developments in the functional food and beverage market discussed in this review could serve as a reference for researchers and industrialist.

Dress me an outfit: advanced probiotics hybrid systems for intelligent IBD therapy

Inflammation bowel disease (IBD) has emerged as a public health challenge worldwide; with high incidence and rapid prevalence, it has troubled billions of people and further induced multitudinous systemic complications. Recent decade has witnessed the vigorous application of food-borne probiotics for IBD therapy; however, the complicated and changeable environments of digestive tract have forced probiotics to face multiple in vivo pressures, consequently causing unsatisfied prophylactic or therapeutic efficacy attributed to off-targeted arrival, damaged viability, insufficient colonization efficiency, etc. Fortunately, arisen hybrid technology has provided versatile breakthroughs for the targeted transplantation of probiotics. By ingeniously modifying probiotics to form probiotics hybrid systems (PHS), the biological behaviors of probiotics in vivo could be mediated, the interactions between probiotics with intestinal components can be facilitated, and diverse advanced probiotic-based therapies for IBD challenge can be developed, which attribute to the intelligent response to microenvironment of PHS, and intelligent design of PHS for multiple functions combination. In this review, various PHS were categorized and their intestinal behaviors were elucidated systematically, their therapeutic effects and intrinsic mechanism were further analyzed. Besides, shortages of present PHS and the corresponding solutions have been discussed, based on which the future perspectives of this field have also been proposed. The undeniable fact is that PHS show an incomparable future to bring the next generation of advanced food science.

Protective Effects of Laminaria japonica Polysaccharide Composite Microcapsules on the Survival of Lactobacillus plantarum during Simulated Gastrointestinal Digestion and Heat Treatment

To improve probiotics' survivability during gastrointestinal digestion and heat treatment, Lactobacillus plantarum was microencapsulated by spray-drying using Laminaria japonica polysaccharide/sodium caseinate/gelatin (LJP/SC/GE) composites. Thermogravimetry and differential scanning calorimetry results revealed that the denaturation of LJP/SC/GE microcapsules requires higher thermal energy than that of SC/GE microcapsules, and the addition of LJP may improve thermal stability. Zeta potential measurements indicated that, at low pH of the gastric fluid, the negatively charged LJP attracted the positively charged SC/GE, helping to maintain an intact microstructure without disintegration. The encapsulation efficiency of L. plantarum-loaded LJP/SC/GE microcapsules reached about 93.4%, and the survival rate was 46.9% in simulated gastric fluid (SGF) for 2 h and 96.0% in simulated intestinal fluid (SIF) for 2 h. In vitro release experiments showed that the LJP/SC/GE microcapsules could protect the viability of L. plantarum in SGF and release probiotics slowly in SIF. The cell survival of LJP/SC/GE microcapsules was significantly improved during the heat treatment compared to SC/GE microcapsules and free cells. LJP/SC/GE microcapsules can increase the survival of L. plantarum by maintaining the lactate dehydrogenase and Na+-K+-ATPase activity. Overall, this study demonstrates the great potential of LJP/SC/GE microcapsules to protect and deliver probiotics in food and pharmaceutical systems.

Microencapsule delivery systems of functional substances for precision nutrition

Microencapsulation, a typical core-shell structure technology, encapsulates functional active ingredients for protection, controlled release, and targeted delivery. In precise nutrition, the focus is on utilizing microcapsule delivery systems for personalized dietary supplements and disease intervention. This chapter outlines the morphological structure of microcapsules, common wall materials, and preparation techniques. It discusses the characteristics of different hydrophilic and lipophilic functional factors and their function as dietary supplements. The role of microencapsulation on the controlled release, odor masking, and enhanced bioavailability of functional factors is explored. Additionally, the application of microcapsule delivery systems in nutritional interventions for diseases like inflammatory bowel disease, alcoholic/fatty liver disease, diabetes, and cancer is introduced in detail. Lastly, the chapter proposes the future developments of anticipation in responsive wall materials for precise nutrition interventions, including both challenges and opportunities.

Techniques, applications and prospects of polysaccharide and protein based biopolymer coatings: A review

The growing relevance of sustainable materials has recently led to the exploration of naturally derived biopolymeric hydrogels as coating materials due to their biodegradability, biocompatibility, ease of fabrication and modification. Although many review articles exist on biopolymeric coatings, they mainly focus on a specific polysaccharide, protein biopolymer, or a particular application- biomedical engineering or food preservation. The current review first summarizes the commonly used polysaccharide and protein-based biopolymers like chitosan, alginate, carrageenan, pectin, cellulose, starch, pullulan, agarose and silk fibroin, gelatin, respectively, with a systematic description of the techniques widely used for physical coating on substrates. Then, broad applications of these biopolymeric coatings on various substrates in biomedical engineering- 3D scaffolds, biomedical implants, and nanoparticles are described in detail. It also entails the application of biopolymeric coatings for food preservation in the form of food packaging and edible coatings. A brief discussion on the newly discovered interest in exploring biopolymers for anticorrosive coating applications is also included. Finally, concluding remarks on the role of biopolymer microstructures in forming homogeneous coatings, prospective alternatives to the currently used biopolymers as coating material and the advent of computer-aided technologies to expedite experimental findings are presented.

Application of biomacromolecules encapsulation systems for the long-term storage of Lactobacillus plantarum F1 and Lactobacillus reuteri 182

The aim of this study was to improve the viability of lactic acid bacteria (LAB) during extended storage of 1 year and mechanical characteristics of the calcium alginate beads with co-encapsulation of prebiotics and chitosan coating and subsequent freeze drying. The results revealed that the addition of trehalose to alginate matrix effectively protects the LAB cells during freeze drying, i.e., the survival rate has increased up to more than 92.5 %. Chitosan coating reinforced Ca-alginate beads, therefore the sphericity and mechanical strength of the beads improved. The findings also showed that bacteria encapsulation with the prebiotics resulted in more cells stability during the prolonged storage of 1 year and were 4.82 ± 0.06 log CFU g-1 in the lyophilized alginate-trehalose beads for Lactobacillus plantarum and 5.64 ± 0.08 log CFU g-1 in the lyophilized alginate-trehalose-inulin beads for Lactobacillus reuteri. No survival, however, was noted for the LAB cells in wet capsules after the same period. This study demonstrated that prebiotics had a significant impact on the viability of cells during freeze drying and storage. What is more, physical properties of the alginate beads were enhanced by coating beads with the chitosan.

Bifidobacterium species viability in dairy-based probiotic foods: challenges and innovative approaches for accurate viability determination and monitoring of probiotic functionality

Bifidobacterium species are essential members of a healthy human gut microbiota. Their presence in the gut is associated with numerous health outcomes such as protection against gastrointestinal tract infections, inflammation, and metabolic diseases. Regular intake of Bifidobacterium in foods is a sustainable way of maintaining the health benefits associated with its use as a probiotic. Owing to their global acceptance, fermented dairy products (particularly yogurt) are considered the ideal probiotic carrier foods. As envisioned in the definition of probiotics as "live organisms," the therapeutic functionalities of Bifidobacterium spp. depend on maintaining their viability in the foods up to the point of consumption. However, sustaining Bifidobacterium spp. viability during the manufacture and shelf-life of fermented dairy products remains challenging. Hence, this paper discusses the significance of viability as a prerequisite for Bifidobacterium spp. probiotic functionality. The paper focuses on the stress factors that influence Bifidobacterium spp. viability during the manufacture and shelf life of yogurt as an archetypical fermented dairy product that is widely accepted as a delivery vehicle for probiotics. It further expounds the Bifidobacterium spp. physiological and genetic stress response mechanisms as well as the methods for viability retention in yogurt, such as microencapsulation, use of oxygen scavenging lactic acid bacterial strains, and stress-protective agents. The report also explores the topic of viability determination as a critical factor in probiotic quality assurance, wherein, the limitations of culture-based enumeration methods, the challenges of species and strain resolution in the presence of lactic acid bacterial starter and probiotic species are discussed. Finally, new developments and potential applications of next-generation viability determination methods such as flow cytometry, propidium monoazide-quantitative polymerase chain reaction (PMA-qPCR), next-generation sequencing, and single-cell Raman spectroscopy (SCRS) methods are examined.

Advances in polysaccharides for probiotic delivery: Properties, methods, and applications

Probiotics are essential to improve the health of the host, whereas maintaining the viability of probiotics in harsh environments remains a challenge. Polysaccharides have non-toxicity, excellent biocompatibility, and outstanding biodegradability, which can protect probiotics by forming a physical barrier and show a promising prospect for probiotic delivery. In this review, we summarize polysaccharides commonly used for probiotic microencapsulation and introduce the microencapsulation technologies, including extrusion, emulsion, spray drying, freeze drying, and electrohydrodynamics. We discuss strategies for better protection of probiotics and introduce the applications of polysaccharides-encapsulated probiotics in functional food, oral formulation, and animal feed. Finally, we propose the challenges of polysaccharides-based delivery systems in industrial production and application. This review will help provide insight into the advances and challenges of polysaccharides in probiotic delivery.

Microencapsulation of Bacillus subtilis and oat β-glucan and their application as a synbiotic in fish feed

To improve survival during storage and exposure to adverse conditions, Bacillus subtilis was microencapsulated with oat β-glucan by spray-drying technology. The characterisation of the microcapsules was designed to compare free and microencapsulated cells through exposure to simulated gastric fluids (SGF) throughout storage for 90 days at different temperatures. The characterisation included analysis of efficiency, morphology, moisture, water activity, hygroscopicity, particle size, and zeta potential. The microcapsules presented a particle size of 1.5 ± 0.34 μm and an encapsulation efficiency of 77.9 ± 3.06%. After SGF, the survival of microencapsulated cells was 8.4 ± 0.07 log CFU mL-1 while that of free cells was 7.6 ± 0.06 log CFU mL-1. After 90 days of storage, only microencapsulated cells remained above 6 log-unit of viability. In conclusion, spray-drying technique combined with the addition of oat β-glucan proved to be an efficient method to protect B. subtilis under storage and SGF with potential application in fish feed.

Carbohydrate polymer-based carriers for colon targeted delivery of probiotics

Probiotics (PRO) have been recognized for their significant role in promoting human health, particularly in relation to colon-related diseases. The effective delivery of PRO to the colon is a fascinating area of research. Among various delivery materials, carbohydrates have shown great potential as colon-targeted delivery (CTD) carriers for PRO. This review explores the connection between probiotics and colonic diseases, delving into their underlying mechanisms of action. Furthermore, it discusses current strategies for the targeted delivery of active substances to the colon. Unlike other reviews, this work specifically focuses on the utilization of carbohydrates, such as alginate, chitosan, pectin, and other carbohydrates, for probiotic colon-targeted delivery applications. Carbohydrates can undergo hydrolysis at the colonic site, allowing their oligosaccharides to function as prebiotics or as direct functional polysaccharides with beneficial effects. Furthermore, the development of multilayer self-assembled coatings using different carbohydrates enables the creation of enhanced delivery systems. Additionally, chemical modifications of carbohydrates, such as for adhesion and sensitivity, can be implemented to achieve more customized delivery of PRO.

Milk fat globule membrane: composition, production and its potential as encapsulant for bioactives and probiotics

Milk fat globule membrane (MFGM) is a complex trilayer structure present in mammalian milk and is mainly composed of phospholipids and proteins (>90%). Many studies revealed MFGM has positive effects on the immune system, brain development, and cognitive function of infants. Probiotics are live microorganisms that have been found to improve mental health and insulin sensitivity, regulate immunity, and prevent allergies. Probiotics are unstable and prone to degradation by environmental, processing, and storage conditions. In this review, the processes used for encapsulation of probiotics particularly the potential of MFGM and its constituents as encapsulating materials for probiotics are described. This study analyzes the importance of MFGM in encapsulating bioactive substances and emphasizes the interaction with probiotics and the gut as well as its resistance to adverse environmental factors in the digestive system when used as a probiotic embedding material. MFGM can enhance the gastric acid resistance and bile resistance of probiotics, mainly manifested in the survival rate of probiotics. Due to the role of digestion, MFGM-coated probiotics can be released in the intestine, and due to the biocompatibility of the membrane, it can promote the binding of probiotics to intestinal epithelial cells, and promote the colonization of some probiotics in the intestine.

Fabrication of whey protein/pectin double layer microcapsules for improving survival of Lacticaseibacillus rhamnosus ZFM231

To improve the viability of Lacticaseibacillus rhamnosus ZFM231 strain in the gastrointestinal tract and exhibit better probiotic effect, an internal emulsification/gelation technique was employed to encapsulate this strain using whey protein and pectin as wall materials to fabricate the double layer microcapsules. Four key factors affecting the encapsulation process were optimized using single factor analysis and response surface methodology. Encapsulation efficiency of L. rhamnosus ZFM231 reached 89.46 ± 0.82 %, the microcapsules possessed a particle size of 172 ± 1.80 μm and ζ-potential of -18.36 mV. The characters of the microcapsules were assessed using optical microscope, SEM, FT-IR and XRD analysis. It was found that after exposure to simulated gastric fluid, the bacterial count (log (CFU g^-1)) of the microcapsules only lost 1.96 units, the bacteria were released readily in simulated intestinal fluid, reaching 86.56 % after 90 min. After stored at 4 °C for 28 days and 25 °C for 14 days, bacterial count of the dry microcapsules decreased from 10.59 to 9.02 and 10.49 to 8.70 log (CFU g^-1), respectively. The double layered microcapsules could significantly increase the storage and thermal abilities of bacteria. Such L. rhamnosus ZFM231 microcapsules could find applications as ingredient of the functional foods and the dairy products.

Membrane Emulsification as an Emerging Method for Lacticaseibacillus rhamnosus GG® Encapsulation

Techniques capable of producing small-sized probiotic microcapsules with high encapsulation yields are of industrial and scientific interest. In this study, an innovative membrane emulsification system was investigated in the production of microcapsules containing Lacticaseibacillus rhamnosus GG® (Lr), sodium alginate (ALG), and whey protein (WPI), rice protein (RPC), or pea protein (PPC) as encapsulating agents. The microcapsules were characterized by particle size distribution, optical microscopy, encapsulation yield, morphology, water activity, hygroscopicity, thermal properties, Fourier-transform infrared spectroscopy (FTIR), and probiotic survival during in vitro simulation of gastrointestinal conditions. The innovative encapsulation technique resulted in microcapsules with diameters varying between 18 and 29 μm, and encapsulation yields > 93%. Combining alginate and whey, rice, or pea protein improved encapsulation efficiency and thermal properties. The encapsulation provided resistance to gastrointestinal fluids, resulting in high probiotic viability at the end of the intestinal phase (> 7.18 log CFU g-1). The proposed encapsulation technology represents an attractive alternative to developing probiotic microcapsules for future food applications.

Graphical Abstract

Supplementary Information

The online version contains supplementary material available at 10.1007/s11947-023-03099-w.

Construction of Probiotic Double-Layered Multinucleated Microcapsules Based on Sulfhydryl-Modified Carboxymethyl Cellulose Sodium for Increased Intestinal Adhesion of Probiotics and Therapy for Intestinal Inflammation Induced by Escherichia coli O157:H7

The decreased number of viable bacteria and the ability of Bifidobacterium to adhere to and colonize the gut in the gastrointestinal environment greatly limit their efficacy. To solve this problem, thiolated carboxymethyl cellulose sodium (CMC) probiotic double-layered multinucleated microcapsules with Bifidobacterium adolescentis FS2-3 in the inner layer and Bacillus subtilis SN15-2 embedded in the outer layers were designed. First, the viable counts and release rates of microcapsules were examined by in vitro simulated digestion assays, and it was found that microcapsules were better protected from gastrointestinal digestion than the controls. Compared with free Bifidobacterium strains, double-layered multinucleated microcapsules have higher viable bacterial survival rates and storage stability. Second, through in vitro rheology, tensile tests, isotherm titration calorimetry, and adhesion tests, it was observed that thiolated CMC could enhance the strong interaction of Bifidobacterium with intestinal mucus and significantly promote the proliferation and growth of probiotics. Finally, double-layered multinucleated microcapsules containing B. adolescentis FS2-3 and B. subtilis SN15-2 modified with sulfhydryl-modified CMC were studied in the intestine. Alleviation of Escherichia coli O157:H7 induced intestinal inflammation. The results showed that microencapsulation could significantly increase the colon content of Bifidobacterium, relieve intestinal inflammation symptoms in mice with bacterial enteritis, and repair the intestinal microbiota disorder caused by inflammation. The probiotic double-layered multinucleated microcapsules prepared in this study can improve the survival rate of probiotics and promote proliferation, adhesion, and colonization of probiotics.

Chitosan-Coated Alginate Microcapsules of a Full-Spectrum Cannabis Extract: Characterization, Long-Term Stability and In Vitro Bioaccessibility

Cannabinoids present in Cannabis sativa are increasingly used in medicine due to their therapeutic potential. Moreover, the synergistic interaction between different cannabinoids and other plant constituents has led to the development of full-spectrum formulations for therapeutic treatments. In this work, the microencapsulation of a full-spectrum extract via vibration microencapsulation nozzle technique using chitosan-coated alginate is proposed to obtain an edible pharmaceutical-grade product. The suitability of microcapsules was assessed by their physicochemical characterization, long-term stability in three different storage conditions and in vitro gastrointestinal release. The synthetized microcapsules contained mainly ∆9-tetrahydrocannabinol (THC)-type and cannabinol (CBN)-type cannabinoids and had a mean size of 460 ± 260 µm and a mean sphericity of 0.5 ± 0.3. The stability assays revealed that capsules should be stored only at 4 °C in darkness to maintain their cannabinoid profile. In addition, based on the in vitro experiments, a fast intestinal release of cannabinoids ensures a medium-high bioaccessibility (57-77%) of therapeutically relevant compounds. The full characterization of microcapsules indicates that they could be used for the design of further full-spectrum cannabis oral formulations.

Development of engineered probiotics with tailored functional properties and their application in food science

The potential health benefits of probiotics may not be cognized because of the substantial curtailment in their viability during food storage and passage through the gastrointestinal system. Intestinal flora composition, and resistance against pathogens are among the health benefits associated with probiotic consumption. In the gastric environment, pH 2.0, probiotics dramatically lose their viability during the transit through the gastrointestinal system. The challenge remains to maintain cell viability until it reaches the large intestine. In extreme conditions, such as a decrease in pH or an increase in temperature, encapsulation technology can enhance the viability of probiotics. Probiotic bacterial strains can be encapsulated in a variety of ways. The methods are broadly systematized into two categories, liquid and solid delivery systems. This review emphasizes the technology used in the research and commercial sectors to encapsulate probiotic cells while keeping them alive and the food matrix used to deliver these cells to consumers.

Graphical abstract

Microencapsulation of Probiotics with Soy Protein Isolate and Alginate for the Poultry Industry

Many probiotic products, with properly selected microorganisms, may not be effective for the intended purpose due to the low tolerance of microorganisms to gastrointestinal digestion. The microencapsulation seems to be one of the most promising techniques to protect probiotics against adverse environmental conditions. Therefore, the aim of this work was the design of soy protein isolate-alginate microcapsules for the encapsulation of probiotics for the poultry industry by the water-in-oil emulsion technique. To this end, the strain Ligilactobacillus salivarius CRL2217, with the ability to bind wheat germ agglutinin (WGA) on its surface and protect intestinal epithelial cells from the cytotoxicity of the glycoprotein, was used as model microorganism. Several parameters were varied in order to find the better conditions for microencapsulation: oil source and nature, SPI and sodium alginate concentration, stirring equipment and time for emulsion formation, CaCl2 concentration, and absence or presence of stirring after the addition of the CaCl2 solution. The survival of entrapped cells to a simulated gastric digestion and their survival and release during simulated intestinal digestion were also investigated. The obtained particles effectively protected L. salivarius CRL2217 from the proteolytic activity and low pH present in the gastric environment. Besides, their content was released in contact with a simulated intestinal juice, as viable counts and binding of WGA after a simulated intestinal digestion revealed. This work paves the way for the design of probiotic supplements for poultry including gastrointestinal digestion-susceptible bacteria.

Fabrication of electrospun gum Arabic-polyvinyl alcohol blend nanofibers for improved viability of the probiotic

In the current study, the probiotic (Lactobacillus acidophilus) was encapsulated using Gum Arabic and polyvinyl alcohol blended nanofibers by electrospinning. Obtained nanofibers were characterized in terms of particle size, diameter, mechanical strength, and encapsulation efficiency. The molecular and internal structure characterization was carried out using Fourier transform infrared spectroscopy and X-ray diffraction respectively. Thermo Gravimetric (TGA) analysis was conducted to determine the thermal features of PVA/GA/probiotics nanofibers. Free and encapsulated probiotics were also subjected to in vitro assay under different detrimental conditions. Images obtained using SEM indicated that probiotics were successfully encapsulated in blends by a nano-spider. FTIR and XRD spectra showed bonding interactions between the wall and core materials. In-vitro assay indicated that probiotics with encapsulated showed significantly (P < 0.05) viability compared to free cells. Free cells lost their viability under simulated gastrointestinal conditions while encapsulated cells retained viability count above the therapeutic number (107 cfu).

Preparation and Characteristics of Alginate Microparticles for Food, Pharmaceutical and Cosmetic Applications

Alginates are the most widely used natural polymers in the pharmaceutical, food and cosmetic industries. Usually, they are applied as a thickening, gel-forming and stabilizing agent. Moreover, the alginate-based formulations such as matrices, membranes, nanospheres or microcapsules are often used as delivery systems. Alginate microparticles (AMP) are biocompatible, biodegradable and nontoxic carriers, applied to encapsulate hydrophilic active substances, including probiotics. Here, we report the methods most frequently used for AMP production and encapsulation of different actives. The technological parameters important in the process of AMP preparation, such as alginate concentration, the type and concentration of other reagents (cross-linking agents, oils, emulsifiers and pH regulators), agitation speed or cross-linking time, are reviewed. Furthermore, the advantages and disadvantages of alginate microparticles as delivery systems are discussed, and an overview of the active ingredients enclosed in the alginate carriers are presented.

Physical, Chemical, and Biological Properties of Chitosan-Coated Alginate Microparticles Loaded with Porcine Interleukin-1β: A Potential Protein Adjuvant Delivery System

We previously developed chicken interleukin-1β (IL-1β) mutants as single-dose adjuvants that induce protective immunity when co-administered with an avian vaccine. However, livestock such as pigs may require a vaccine adjuvant delivery system that provides long-lasting protection to reduce the need for successive booster doses. Therefore, we developed chitosan-coated alginate microparticles as a carrier for bovine serum albumin (BSA) or porcine IL-1β (pIL-1β) and assessed their physical, chemical, and biological properties. Electrospraying of the BSA-loaded alginate microparticles (BSA/ALG MPs) resulted in an encapsulation efficiency of 50%, and those MPs were then coated with chitosan (BSA/ALG/CHI MPs). Optical and scanning electron microscopy, zeta potential analysis, and Fourier transform infrared spectroscopy were used to characterize these MPs. The BSA encapsulation parameters were applied to ALG/CHI MPs loaded with pIL-1β, which were not cytotoxic to porcine fibroblasts but had enhanced bio-activity over unencapsulated pIL-1β. The chitosan layer of the BSA/ALG/CHI MPs prevented burst release and facilitated sustained release of pIL-1β for at least 28 days. In conclusion, BSA/ALG/CHI MPs prepared as a carrier for pIL-1β may be used as an adjuvant for the formulation of pig vaccines.

Antimicrobial potential of probiotic cell-free and Carum copticum L. seed extracts co-nanoencapsulated in cellulose acetate fibers

The aim of this work was to co-nanoencapsulate Lactobacillus acidophilus (LCFE) and Bifidobacterium bifidum (BCFE) cell-free extract and zenyan (Carum copticum L.) seed water (ZWE) and ethanolic (ZEE) extract in electrospun cellulose acetate (CA) nanofibers and evaluate antimicrobial potential. The zeta potential, SEM image, antibacterial (MIC and MBC), and antifungal (MIC and MFC) activities were evaluated. TPC (total phenol content) of water and ethanol extract of zenyan seed were 14.05 and 136.44 mg GAE/g, respectively. A zeta potential of -40.25, -45.80, -43.71, 48.55, 35.50, 47.93, 31.50, 44.69, and -29.61 mV was found for nanofibers of pure CA (cellulose acetate), CA/LCFE, CA/BCFE, CA/ZWE, CA/ZEE, CA/LCFE/ZWE, CA/LCFE/ZEE, CA/BCFE/ZWE, and CA/LCFE/ZEE, respectively. CA electrospun nanofiber loaded with different extracts showed nanosized diameter and uniform structure. Nanoencapsulated extracts showed considerably higher antibacterial and antifungal activity compared to free extracts. Antibacterial activity of lactobacilli cell-free extract was higher than bifidobacteria, which indicated the presence of the higher amount of antibacterial compounds in lactobacilli extract. Gram-positive bacteria (S. aureus and L. monocytogenes) had the lowest MIC and MBC of free and nanoencapsulated extracts while Gram-negatives (E. coli, S. dysenteriae, and S. enteritidis) had higher MIC and MBC. CA-coated zenyan extracts (water and ethanolic) inhibited the growth of the assayed fungi at the MIC ranging 0.25 to 0.95%. These concentrations were 1.5-2 times lower than those obtained for pure extracts. For nanoencapsulated cell-free extracts of both probiotics, the MIC values were about five times lower than the free extracts. The highest antimicrobial activity obtained for CA nanofibers contained zenyan ethanolic extract and cell-free extract of lactobacilli or bifidobacteria.

Advances in polysaccharide-based nano/microcapsules for biomedical applications: A review

Biocompatible and biodegradable polysaccharides are abundant and renewable natural materials. Polysaccharides and their derivatives are developed into various carrier materials for biomedical applications. In particular, advanced polysaccharide-based nano/microcapsules have received extensive attention in biomedical applications due to their good encapsulation ability and tunability. In recent years, polysaccharide-based nano/microcapsules have been widely used in drug carriers, gene carriers, antigen carriers, wound dressings, bioimaging and biosensors. Numerous research results have confirmed the feasibility, safety, and effectiveness of polysaccharide-based nano/microcapsules in the above-mentioned biomedical applications. This review discussed and analyzed the latest research strategies and design considerations for these applications in detail. The preparation methods, application strategies, and design considerations of polysaccharide-based nano/microcapsules are summarized and analyzed, and their challenges and future research prospects in biomedicine are further discussed. It is expected to provide researchers with inspiration and design ideas.

Novel nano-encapsulated probiotic agents: Encapsulate materials, delivery, and encapsulation systems

Gut microbes are closely associated with most human health. When ingested orally, probiotics can effectively regulate the composition and quantity of human intestinal microorganisms, which is beneficial to human health. However, probiotics will be affected by the harsh environment of the digestive tract during the in vivo transportation process, and ensuring the viability of probiotics is a great challenge. Probiotic encapsulating technology provides an effective solution to this problem. The introduction of extreme temperatures, large probiotic microcapsule sizes and the difficulty in controlling probiotic microcapsule particle sizes mean that traditional microcapsule encapsulation methods have some limitations. From traditional microcapsule technology to the bulk encapsulation of probiotics with nanofibers and nanoparticles to the recent ability to wear nano "armor" for a single probiotic through biofilm, biological membrane and nanocoating. Emerging probiotic nanoagents provides a new conceptual and development direction for the field of probiotic encapsulation. In this review, we presented the characteristics of encapsulated probiotic carrier materials and digestive tract transport systems, we focused on the encapsulation systems of probiotic nanoagents, we analyzed the shortcomings and advantages of the current agent encapsulation systems, and we stated the developmental direction and challenges for these agents for the future.

Biopolymer-Based Multilayer Microparticles for Probiotic Delivery to Colon

The potential health benefits of probiotics may not be realized because of the substantial reduction in their viability during food storage and gastrointestinal transit. Microencapsulation has been successfully utilized to improve the resistance of probiotics to critical conditions. Owing to the unique properties of biopolymers, they have been prevalently used for microencapsulation of probiotics. However, majority of microencapsulated products only contain a single layer of protection around probiotics, which is likely to be inferior to more sophisticated approaches. This review discusses emerging methods for the multilayer encapsulation of probiotic using biopolymers. Correlations are drawn between fabrication techniques and the resultant microparticle properties. Subsequently, multilayer microparticles are categorized based on their layer designs. Recent reports of specific biopolymeric formulations are examined regarding their physical and biological properties. In particular, animal models of gastrointestinal transit and disease are highlighted, with respect to trials of multilayer microencapsulated probiotics. To conclude, novel materials and approaches for fabrication of multilayer structures are highlighted.

Microencapsulating Alginate-Based Polymers for Probiotics Delivery Systems and Their Application

Probiotics exhibit many health benefits and a great potential for broad applications in pharmaceutical fields, such as prevention and treatment of gastrointestinal tract diseases (irritable bowel syndrome), prevention and therapy of allergies, certain anticancer effects, and immunomodulation. However, their applications are limited by the low viability and metabolic activity of the probiotics during processing, storage, and delivery in the digestive tract. To overcome the mentioned limitations, probiotic delivery systems have attracted much attention. This review focuses on alginate as a preferred polymer and presents recent advances in alginate-based polymers for probiotic delivery systems. We highlight several alginate-based delivery systems containing various types of probiotics and the physical and chemical modifications with chitosan, cellulose, starch, protein, fish gel, and many other materials to enhance their performance, of which the viability and protective mechanisms are discussed. Withal, various challenges in alginate-based polymers for probiotics delivery systems are traced out, and future directions, specifically on the use of nanomaterials as well as prebiotics, are delineated to further facilitate subsequent researchers in selecting more favorable materials and technology for probiotic delivery.

Encapsulation of probiotics: past, present and future

Background

Probiotics are live microbial supplements known for its health benefits. Consumption of probiotics reported to improve several health benefits including intestinal flora composition, resistance against pathogens. In the recent years, there is an increasing trend of probiotic-based food products in the market.

Main body

Probiotics cells are targeted to reach the large intestine, and the probiotics must survive through the acidic conditions of the gastric environment. It is recommended to formulate the probiotic bacteria in the range of 108–109 cfu/g for consumption and maintain the therapeutic efficacy of 106–107 cfu/g in the large intestine. During the gastrointestinal transit, the probiotics will drastically lose its viability in the gastric environment (pH 2). Maintaining cell viability until it reaches the large intestine remains challenging task. Encapsulating the probiotics cells with suitable wall material helps to sustain the survival of probiotics during industrial processing and in gastrointestinal transit. In the encapsulation process, cells are completely enclosed in the wall material, through different techniques including spray drying, freeze drying, extrusion, spray freeze drying, emulsification, etc. However, spray-drying and freeze-drying techniques are successfully used for the commercial formulation; thus, we limited to review those encapsulation techniques.

Short conclusions

The survival rate of spray-dried probiotics during simulated digestion mainly depends on the inlet air temperature, wall material and exposure in the GI condition. And fermentation, pH and freeze-drying time are the important process parameters for maintaining the viability of bacterial cells in the gastric condition. Improving the viability of probiotic cells during industrial processing and extending the cell viability during storage and digestion will be the main concern for successful commercialization.

Graphical abstract

Encapsulation of Plant Biocontrol Bacteria with Alginate as a Main Polymer Material

One of the most favored trends in modern agriculture is biological control. However, many reports show that survival of biocontrol bacteria is poor in host plants. Providing biocontrol agents with protection by encapsulation within external coatings has therefore become a popular idea. Various techniques, including extrusion, spray drying, and emulsion, have been introduced for encapsulation of biocontrol bacteria. One commonly used biopolymer for this type of microencapsulation is alginate, a biopolymer extracted from seaweed. Recent progress has resulted in the production of alginate-based microcapsules that meet key bacterial encapsulation requirements, including biocompatibility, biodegradability, and support of long-term survival and function. However, more studies are needed regarding the effect of encapsulation on protective bacteria and their targeted release in organic crop production systems. Most importantly, the efficacy of alginate use for the encapsulation of biocontrol bacteria in pest and disease management requires further verification. Achieving a new formulation based on biodegradable polymers can have significant effects on increasing the quantity and quality of agricultural products.

Microencapsulation: a pragmatic approach towards delivery of probiotics in gut

Probiotics confer numerous health benefits and functional foods prepared with these microbes own largest markets. However, their viability during transit from gastrointestinal tract is a concerning issue. Microencapsulation of probiotics is a novel technique of major interest to increase their survivability in GIT and food matrices by providing a physical barrier to protect them under harsh conditions. This article contributes the knowledge regarding microencapsulation by discussing probiotic foods, different methods and approaches of microencapsulation, coating materials, their release mechanisms at the target site, and interaction with probiotics, efficiency of encapsulated probiotics, their viability assessment methods, applications in food industry, and their future perspective. In our opinion, encapsulation has significantly got importance in the field of innovative probiotic enriched functional foods development to preserve their viability and long-term survival rate until product expiration date and their passage through gastro-intestinal tract. Previous review work has targeted some aspects of microencapsulation, this article highlights different methods of probiotics encapsulation and coating materials in relation with food matrices as well as challenges faced during applications: Gut microbiota; Lactic acid bacteria; Micro-encapsulation; Stability enhancement; Cell's release, Health benefits.

Inclusion of Probiotics into Fermented Buffalo (Bubalus bubalis) Milk: An Overview of Challenges and Opportunities

Buffalo-milk-based dairy products provide various health benefits to humans since buffalo milk serves as a rich source of protein, fat, lactose, calcium, iron, phosphorus, vitamin A and natural antioxidants. Dairy products such as Meekiri, Dadih, Dadi and Lassie, which are derived from Artisanal fermentation of buffalo milk, have been consumed for many years. Probiotic potentials of indigenous microflora in fermented buffalo milk have been well documented. Incorporation of certain probiotics into the buffalo-milk-based dairy products conferred vital health benefits to the consumers, although is not a common practice. However, several challenges are associated with incorporating probiotics into buffalo-milk-based dairy products. The viability of probiotic bacteria can be reduced due to processing and environmental stress during storage. Further, incompatibility of probiotics with traditional starter cultures and high acidity of fermented dairy products may lead to poor viability of probiotics. The weak acidifying performance of probiotics may affect the organoleptic quality of fermented dairy products. Besides these challenges, several innovative technologies such as the use of microencapsulated probiotics, ultrasonication, the inclusion of prebiotics, use of appropriate packaging and optimal storage conditions have been reported, promising stability and viability of probiotics in buffalo-milk-based fermented dairy products.