Influence of l-cysteine, oxygen and relative humidity upon survival throughout storage of probiotic bacteria in whey protein-based microcapsules

Protein-polysaccharide based double network microbeads improves stability of Bifidobacterium infantis ATCC 15697 in a gastro-Intestinal tract model (TIM-1)

Microencapsulation of probiotics is a main technique employed to improve cell survival in gastrointestinal tract (GIT). The present study investigated the impact of utilizing proteins i.e. Whey Protein Isolates (WPI), Pea Protein Isolates (PPI) or (WPI + PPI) complex based microbeads as encapsulating agents on the encapsulation efficiency (EE), diameter, morphology along with the survival and viability of Bifidobacterium infantis ATCC 15697. Results revealed that WPI + PPI combination had the highest EE% of the probiotics up to 94.09 % and the smoothest surface with less visible holes. WPI based beads revealed lower EE% and smaller size than PPI based ones. In addition, WPI based beads showed rough surface with visible signs of cracks, while PPI beads showed dense surfaces with pores and depressions. In contrast, the combination of the two proteins resulted in compact and smooth beads with less visible pores/wrinkles. The survival in gastrointestinal tract (GIT) was observed through TNO in-vitro gastrointestinal model (TIM-1) and results illustrated that all microbeads shrank in gastric phase while swelled in intestinal phase. In addition, in-vitro survival rate of free cells was very low in gastric phase (18.2 %) and intestinal phase (27.5 %). The free cells lost their viability after 28 days of storage (2.66 CFU/mL) with a maximum log reduction of 6.76, while all the encapsulated probiotic showed more than 106-7 log CFU/g viable cell. It was concluded that encapsulation improved the viability of probiotics in GIT and utilization of WPI + PPI in combination provided better protection to probiotics.

Structured soft particulate matters for delivery of bioactive compounds in foods and functioning in the colon

The present review discusses challenges, perspectives, and current needs of delivering bioactive compounds (BCs) using soft particulate matters (SPMs) for gut health. SPMs can entrap BCs for incorporation in foods, preserve their bioactivities during processing, storage, and gastrointestinal digestion, and deliver BCs to functioning sites in the colon. To enable these functions, physical, chemical, and biological properties of BCs are integrated in designing various types of SPMs to overcome environmental factors reducing the bioavailability and bioactivity of BCs. The design principles are applied using food grade molecules with the desired properties to produce SPMs by additionally considering the cost, sustainability, and scalability of manufacturing processes. Lastly, to make delivery systems practical, impacts of SPMs on food quality are to be evaluated case by case, and health benefits of functional foods incorporated with delivery systems are to be confirmed and must outweigh the cost of preparing SPMs.

Polysaccharides, proteins, and their complex as microencapsulation carriers for delivery of probiotics: A review on carrier types and encapsulation techniques

Probiotics provide several benefits for humans, including restoring the balance of gut bacteria, boosting the immune system, and aiding in the management of certain conditions such as irritable bowel syndrome and lactose intolerance. However, the viability of probiotics may undergo a significant reduction during food storage and gastrointestinal transit, potentially hindering the realization of their health benefits. Microencapsulation techniques have been recognized as an effective way to improve the stability of probiotics during processing and storage and allow for their localization and slow release in intestine. Although, numerous techniques have been employed for the encapsulation of probiotics, the encapsulation techniques itself and carrier types are the main factors affecting the encapsulate effect. This work summarizes the applications of commonly used polysaccharides (alginate, starch, and chitosan), proteins (whey protein isolate, soy protein isolate, and zein) and its complex as the probiotics encapsulation materials; evaluates the evolutions in microencapsulation technologies and coating materials for probiotics, discusses their benefits and limitations, and provides directions for future research to improve targeted release of beneficial additives as well as microencapsulation techniques. This study provides a comprehensive reference for current knowledge pertaining to microencapsulation in probiotics processing and suggestions for best practices gleaned from the literature.

Solving the delivery of Lactococcus lactis: Improved survival and storage stability through the bioencapsulation with different carriers

Probiotics are live microorganisms that confer beneficial effects on the health of the host if administered in adequate amounts (10⁶  CFU viable microorganisms/g of food). As the most frequent route of administration of these microorganisms is oral, the number of them that remains viable through the gastrointestinal tract decreases substantially. Thus, in this research work, we developed a series of alginate-based microparticles using different adjuvants such as methylcellulose, carboxymethylcellulose, chitosan, carbopol, β-cyclodextrin, starch, carrageenan, and Eudragit^® RS 100 as carriers for improving the survival of Lactococcus lactis. The alginate-based formulations exhibited very good drug encapsulation efficiency, up to 90%. Release studies from selected microparticles revealed that almost 100% of bacteria were in solution at 30 min. By scanning electron microscopy, irregular nonporous particles with a size between 200 and 500 µm were seen. In particular, microparticles formulated with alginate-carboxymethylcellulose and alginate-methylcellulose exhibited the best protection for the bacterial cells against both simulated gastric juice and simulated intestinal juice. In addition, those microparticulate systems were able to maintain the viability of the encapsulated bacteria in large numbers for at least 24 weeks. Thus, the present study confirmed that these alginate-based microparticles are a valuable approach for keeping the viability and storage stability of L. lactis.

Natural sources and encapsulating materials for probiotics delivery systems: Recent applications and challenges in functional food development

Probiotics are known as the live microorganisms which upon adequate administration elicit a health beneficial response inside the host by decreasing the luminal pH, eliminating the pathogenic bacteria in the gut as well as producing short chain fatty acids (SCFA). With advancements in research; probiotics have been explored as potential ingredients in foods. However, their use and applications in food industry have been limited due to restrictions of maintaining the viability of probiotic cells and targeting the successful delivery to gut. Encapsulation techniques have significant influence on increasing the viability rates of probiotic cells with the successful delivery of cells to the target site. Moreover, encapsulating techniques also prevent the live cells from harsh physiological conditions of gut. This review discusses several encapsulating techniques as well as materials derived from natural sources and nutraceutical compounds. In addition to this, this paper also comprehensively discusses the factors affecting the probiotics viability and evaluation of successful release and survival of probiotics under simulated gastric, intestinal conditions as well as bile, acid tolerant conditions. Lastly applications and challenges of using encapsulated bacteria in food industry for the development of novel functional foods have also been discussed in detail too. Future studies must include investigating the use of encapsulated bacterial formulations in in-vivo models for effective health beneficial properties as well as exploring the mechanisms behind the successful release of these formulations in gut, hence helping us to understand the encapsulation of probiotic cells in a meticulous manner.

Effect of Novel Lactobacillus paracaesi microcapsule on growth performance, gut health and microbiome community of broiler chickens

The beneficial action of probiotics is questioned time and again due to the loss of their survivability under gastrointestinal conditions, particularly gastric acid. In this experiment, a probiotic species was encapsulated to improve its delivery to the distal parts, and its effects on production performance, gut health, and microbial profile in broilers were investigated. A total of 240 Arbor acres (AA) broilers were randomly allotted into 3 treatments with 8 replicate pens per treatment and 10 broilers in each pen for 42 d. Dietary treatments were 1) basal feed without any additives (CON), 2) CON+15 ppm Virginiamycin (ANT), and 3) CON+500 ppm encapsulated Lactobacillus paracaesi (ELP). The result showed that the addition of ELP to the feed did not affect growth performance and carcass characteristics significantly. However, ELP increased the ratio of villus height to crypt depth (P < 0.05) and mRNA expression of ZO-1 (P < 0.05) relative to the CON or ANT group. Similarly, qPCR showed that dietary supplementation of ELP raised gene expression of the anti-inflammatory cytokine and tended to decrease proinflammatory cytokines resulting improve in immunity. Moreover, chicks fed with ELP had lower malondialdehyde (MDA) (P < 0.05) than CON and lower reactive oxygen species (ROS) (P < 0.05) level than ANT in serum. In contrast, the total antioxidant capacity (TAOC) level was tended to increase. The ammonia level of ileum and cecum chyme was decreased (P < 0.05) in the ELP group than CON while the level of propionic acid of cecal content was increased (P < 0.05). 16S rRNA sequencing revealed the dietary treatment modulated the diversity and composition of cecal microflora. At the phylum level, Bacteroidetes was enriched, and Proteobacteria was depleted in the ELP group. At the genus level, ELP increased Bacteroides (P < 0.05) compared to control. The results indicate that oral delivery of probiotics via microcapsule could impart beneficial effects on birds and be used as an alternative to antibiotics.

Emerging Technologies and Coating Materials for Improved Probiotication in Food Products: a Review

From the past few decades, consumers' demand for probiotic-based functional and healthy food products is rising exponentially. Encapsulation is an emerging field to protect probiotics from unfavorable conditions and to deliver probiotics at the target place while maintaining the controlled release in the colon. Probiotics have been encapsulated for decades using different encapsulation methods to maintain their viability during processing, storage, and digestion and to give health benefits. This review focuses on novel microencapsulation techniques of probiotic bacteria including vacuum drying, microwave drying, spray freeze drying, fluidized bed drying, impinging aerosol technology, hybridization system, ultrasonication with their recent advancement, and characteristics of the commonly used polymers have been briefly discussed. Other than novel techniques, characterization of microcapsules along with their mechanism of release and stability have shown great interest recently in developing novel functional food products with synergetic effects, especially in COVID-19 outbreak. A thorough discussion of novel processing technologies and applications in food products with the incorporation of recent research works is the novelty and highlight of this review paper.

Advancements in the Pharmaceutical Applications of Probiotics: Dosage Forms and Formulation Technology

Probiotics have demonstrated their high potential to treat and/or prevent various diseases including neurodegenerative disorders, cancers, cardiovascular diseases, and inflammatory diseases. Probiotics are also effective against multidrug-resistant pathogens and help maintain a balanced gut microbiota ecosystem. Accordingly, the global market of probiotics is growing rapidly, and research efforts to develop probiotics into therapeutic adjuvants are gaining momentum. However, because probiotics are living microorganisms, many biological and biopharmaceutical barriers limit their clinical application. Probiotics may lose their activity in the harsh gastric conditions of the stomach or in the presence of bile salts. Moreover, they easily lose their viability under thermal or oxidative stress during their preparation and storage. Therefore, stable formulations of probiotics are required to overcome the various physicochemical, biopharmaceutical, and biological barriers and to maximize their therapeutic effectiveness and clinical applicability. This review provides an overview of the pharmaceutical applications of probiotics and covers recent formulation approaches to optimize the delivery of probiotics with particular emphasis on various dosage forms and formulation technologies.

Development and characterization of probiotic mucilage based edible films for the preservation of fruits and vegetables

There is growing interest among the public and scientific community toward the use of probiotics to potentially restore the composition of the gut microbiome. With the aim of preparing eco-friendly probiotic edible films, we explored the addition of probiotics to the seed mucilage films of quince, flax, and basil. These mucilages are natural and compatible blends of different polysaccharides that have demonstrated medical benefits. All three seed mucilage films exhibited high moisture retention regardless of the presence of probiotics, which is needed to help preserve the moisture/freshness of food. Films from flax and quince mucilage were found to be more thermally stable and mechanically robust with higher elastic moduli and elongation at break than basil mucilage films. These films effectively protected fruits against UV light, maintaining the probiotics viability and inactivation rate during storage. Coated fruits and vegetables retained their freshness longer than uncoated produce, while quince-based probiotic films showed the best mechanical, physical, morphological and bacterial viability. This is the first report of the development, characterization and production of 100% natural mucilage-based probiotic edible coatings with enhanced barrier properties for food preservation applications containing probiotics.

Influence of guabiroba pulp (campomanesia xanthocarpa o. berg) added to fermented milk on probiotic survival under in vitro simulated gastrointestinal conditions

In fermented milks inoculated with two thermophilic strains (Lactobacillus bulgaricus and Streptococcus thermophilus), guabiroba pulp (Campomanesia xanthocarpa O. Berg) was added in different concentrations: 5% (I5 sample) and 10% (I10 sample), compared to a control sample, with no pulp addition. In these fermented milks, Bifidobacterium BB-12 was added and the samples were submitted to a progressive gastrointestinal simulation in vitro. The cells count was performed, including the survival rates for all the progressive steps of the simulated digestion. Total phenolic content (TPC) and antioxidant activity analysis by FRAP (Ferric Reducing Antioxidant Power) and DPPH (2,2-diphenyl-1-picrylhydrazyl) were performed in all the gastrointestinal steps. Before and during the entire gastrointestinal tract, the Bifidobacterium BB-12 count was 8-9 log CFU g^-1, above the recommended for a probiotic product, with a highlight in intestinal colon steps. The I10 sample showed the highest viable cell count, the highest total phenolic content and antioxidant activity throughout the entire gastric steps (p < 0.05). The fermented milk proved to be an effective matrix for the probiotic stability and incorporation of guabiroba components. Bioactive compounds present in the guabiroba pulp may have occasioned a prebiotic and protective effect on Bifidobacterium BB-12 after gastric conditions. The possible bioconversion of these compounds in more active forms can contribute to the absorption in epithelial cells, enhancing fermented milks with guabiroba pulp as important sources of dietary accessible bioactive compounds.

Potential of Nanonutraceuticals in Increasing Immunity

Nutraceuticals are defined as foods or their extracts that have a demonstrably positive effect on human health. According to the decision of the European Food Safety Authority, this positive effect, the so-called health claim, must be clearly demonstrated best by performed tests. Nutraceuticals include dietary supplements and functional foods. These special foods thus affect human health and can positively affect the immune system and strengthen it even in these turbulent times, when the human population is exposed to the COVID-19 pandemic. Many of these special foods are supplemented with nanoparticles of active substances or processed into nanoformulations. The benefits of nanoparticles in this case include enhanced bioavailability, controlled release, and increased stability. Lipid-based delivery systems and the encapsulation of nutraceuticals are mainly used for the enrichment of food products with these health-promoting compounds. This contribution summarizes the current state of the research and development of effective nanonutraceuticals influencing the body's immune responses, such as vitamins (C, D, E, B12, folic acid), minerals (Zn, Fe, Se), antioxidants (carotenoids, coenzyme Q10, polyphenols, curcumin), omega-3 fatty acids, and probiotics.

Oxidative stress tolerance and antioxidant capacity of lactic acid bacteria as probiotic: a systematic review

Lactic acid bacteria (LAB) are the most frequently used probiotics in fermented foods and beverages and as food supplements for humans or animals, owing to their multiple beneficial features, which appear to be partially associated with their antioxidant properties. LAB can help improve food quality and flavor and prevent numerous disorders caused by oxidation in the host. In this review, we discuss the oxidative stress tolerance, the antioxidant capacity related herewith, and the underlying mechanisms and signaling pathways in probiotic LAB. In addition, we discuss appropriate methods used to evaluate the antioxidant capacity of probiotic LAB. The aim of the present review is to provide an overview of the current state of the research associated with the oxidative stress tolerance and antioxidant capacity of LAB.

Synbiotic edible film from konjac glucomannan composed of Lactobacillus casei-01® and Orafti®GR, and its application as coating on bread buns

BACKGROUND

Konjac glucomannan-based edible films formulated with Lactobacillus casei-01® and chicory-derived inulin Orafti®GR were studied for their properties, stability, and application as coatings on bread buns.

RESULTS

Thickness and transparency were variable and dependent on the formulations. Alterations in color properties of all supplemented films were unnoticeable by unaided human eyes, with ΔE less than 3. Lactobacillus casei-01® and Orafti®GR were associated with higher water solubility of the films. Lactobacillus casei-01® decreased the water vapor permeability of the films while Orafti®GR promoted it. The mechanical properties in all combinations remained unchanged, although those with Orafti®GR showed profoundly reduced tensile strength. Scanning electron micrographs and Fourier transform infrared spectra of the films confirmed good homogeneity and intermolecular attraction between the prebiotic and konjac glucomannan. Cell viability in the films stored at room temperature decreased sharply, becoming less than the minimum recommended level after day 4, while viable L. casei-01® in coatings on bread buns gradually decreased, with a reduction of ca. 2 log colony-forming units (CFU) portion^-1 over the 7 day storage period at room temperature.

CONCLUSION

The synbiotic film and coating developed in this study are a relatively simple strategy for incorporating L. casei-01® and Orafti®GR into bread buns, which are short shelf-life foods. Bread buns with synbiotic coating could diversify functional food choices. Pretreatment, together with other technologies, is required to maintain a desirable number of active probiotic cells for longer. © 2020 Society of Chemical Industry.

Development of Whey Protein Concentrate-Pectin-Alginate Based Delivery System to Improve Survival of B. longum BL-05 in Simulated Gastrointestinal Conditions

Bifidobacterium longum BL-05 encapsulated beads were developed by using whey protein concentrate (WPC) and pectin (PE) as encapsulating material through extrusion/ionic gelation technique with the objective to improve survival of probiotics in harsh gastrointestinal conditions. B. longum BL-05 was grown in MRS (de man rogosa and sharpe) broth, centrifuged and mixed with polymeric gel solution. Bead formulations E₄ (2.5% WPC + 1.5% PE) and E₅ (2% PE) showed the highest value for encapsulation efficiency, size, and textural properties (hardness, cohesiveness, springiness) due to increasing PE concentration. The survivability and viability of free and encapsulated B. longum BL-05 was assessed through their resistance to simulated gastric juice (SGJ), tolerance to bile salt, release profile in simulated intestinal fluid (SIF), and storage stability during 28 days at 4 °C. The microencapsulation provided protection to B. longum BL-05 and encapsulated cells were exhibited significant (p < 0.05) resistance to SGJ and SIF as compared to free cells. Bead formulations E₃ (5.0% WPC + 1.0% PE) and E₄ (2.5% WPC + 1.5% PE) exhibited more resistance to SGJ (at pH 2 for 2 h) and at 2% bile salt solution but comparatively slow release as compared to other bead formulations. Free cells lost their viability when stored at 4 °C after 28 days but microencapsulated cells demonstrated promising results during storage and viable cell count was > 10⁷ CFU/g. This study revealed that extrusion using WPC and PE as encapsulating material could be considered as one of the novel technologies for protection and effective delivery of probiotics.

Effect of storage and stress conditions on the counts of Bifidobacterium animalis microencapsulated and incorporated in plantain flour

Abstract The probiotic activity in the intestinal microbiota depends on its survival during food storage and its passage through the gastrointestinal tract. This study aimed to evaluate the effect of storage and stress conditions such as temperature, pH and bile salts on the viability of Bifidobacterium animalis microencapsulated and incorporated in plantain flour. Between days 21 and 28, the failure percentage decreased from 93% to 27%. The mean counts of B. animalis were statistically different with change of temperature, pH and bile salt concentration. For the temperature, the counts obtained at 50 °C and 80 °C decreased by 60.1% and 90.2%, respectively. Likewise, at pH 2.5 showed a over 90% survival reduction during 60 min; whilst at pH 3.5 during 60 min the survivals were less than 50%. Finally, the counts achieved using 1 g/L of bile salts were higher than those obtained at 3 and 5 g/L. The results indicate the need to evaluate other capsular components to improve the survival of B. animalis microencapsulated and incorporated in plantain flour.

The Combined Usage of β-Cyclodextrin and Milk Proteins in Microencapsulation of Bifidobacterium bifidum BB-12

The present study aimed to determine the effects of combined usage of β-cyclodextrin with whey protein isolate and sodium caseinate on the microencapsulation of Bifidobacterium bifidum-BB12 by spray drying.From the results, the highest count of B. bifidum was provided by whey protein isolate as 8.62 log CFU/g. The increasing concentration of β-cyclodextrin considerably increases gastric and intestinal resistance to B. bifidum cells. In the gastric and intestinal test, the highest protection was determined in whey protein isolate substituted with 10% β-cyclodextrin with reduction rates of 0.98 and 3.30%, respectively. Moreover, free cells did not survive in the same gastric conditions. The lowest hygroscopicity was determined in whey protein isolate as 8.57%. It must be noted that increasing β-cyclodextrin concentration in carrier material combination led to an increase in hygroscopicity of microcapsules. In general, substitution with β-cyclodextrin increased the particle size of microparticles, and microcapsules produced with whey protein isolate had a smaller size than that of sodium caseinate.

Development of bio-yoghurt chewable tablet: a review

Purpose

This paper aims to discuss the limitations surrounding the yoghurt industry and challenges to producing a bio-yoghurt tablet. The paper looks into challenge facing the yoghurt industry, such as manufacturing and distribution, its short shelf life, heat-sensitivity and relatively heavy weight. It further looks into the selection of strains, excipients and storage conditions with special consideration towards maintaining the viability of the probiotics inside bio-yoghurt tablets. The paper also discusses yoghurt standards and definitions across various countries and suggests a more uniform standard be embraced across countries for ease of categorization and production.

Design/methodology/approach

The paper is divided into a few major sections; each exploring various aspects of the yoghurt industry. Topics discussed include challenges in yoghurt production and storage; processes involved in bio-yoghurt tablet production, e.g. maximising viability, choice of excipients and more; market trends of yoghurt consumption and potential; and various food standards in countries around the world with a focus on yoghurt.

Findings

The review finds that yoghurt is a segment of the food industry with big growth potential. Most of the problems associated with yoghurt, i.e. poor shelf life, and heavy weight, can be circumvented by transforming it into a bio-yoghurt tablet. The paper further identifies food standard variations among different countries around the world which could impede yoghurt manufacture and acceptance.

Originality/value

This paper looks the various challenges surrounding the increased uptake of yoghurt, specifically in the Asian markets and suggests a viable option to overcome this problem, i.e. the use of a bio-yoghurt tablet. Should the worldwide bodies come together and agree to a universal standard involving yoghurt, the industry may see an even bigger expansion.

Probiotics in Food Systems: Significance and Emerging Strategies Towards Improved Viability and Delivery of Enhanced Beneficial Value

Preserving the efficacy of probiotic bacteria exhibits paramount challenges that need to be addressed during the development of functional food products. Several factors have been claimed to be responsible for reducing the viability of probiotics including matrix acidity, level of oxygen in products, presence of other lactic acid bacteria, and sensitivity to metabolites produced by other competing bacteria. Several approaches are undertaken to improve and sustain microbial cell viability, like strain selection, immobilization technologies, synbiotics development etc. Among them, cell immobilization in various carriers, including composite carrier matrix systems has recently attracted interest targeting to protect probiotics from different types of environmental stress (e.g., pH and heat treatments). Likewise, to successfully deliver the probiotics in the large intestine, cells must survive food processing and storage, and withstand the stress conditions encountered in the upper gastrointestinal tract. Hence, the appropriate selection of probiotics and their effective delivery remains a technological challenge with special focus on sustaining the viability of the probiotic culture in the formulated product. Development of synbiotic combinations exhibits another approach of functional food to stimulate the growth of probiotics. The aim of the current review is to summarize the strategies and the novel techniques adopted to enhance the viability of probiotics.

Importance of intact secondary protein structures of cell envelopes and glass transition temperature of the stabilization matrix on the storage stability of probiotics

Lactobacillus reuteri LR6 cells were stabilized using a novel combination of wet granulation and fluidized-bed-drying techniques. The stabilized cells were stored at 37 °C and at two water activity (a_w) levels (0.11 & 0.30). Superior storage stability was recorded in the lower a_w environment, supported by a stronger glassy matrix when skim milk powder was used as the excipient. The initial viable cell populations of the samples stabilized in different matrices ranged from 8.3 to 9.1 log CFU/g. At the end of the storage period, the viable cell populations were reduced to 6.7 to 7.3 log CFU/g at a_w 0.11 and to 6.1 to 6.6 CFU/g when the a_w was maintained at 0.30. Fourier transform infrared spectroscopic examination of the cell envelopes revealed substantial dissimilarities between samples at the beginning and at the end of the storage period, which indicated alteration in the secondary protein structures of the cell envelope and also correlated well with the loss in cell viability. In milk-powder-based matrices, adjusting the a_w to 0.30 resulted in a weaker or no glassy state whereas the same matrices had a high glass transition temperature at a_w 0.11. This strong glassy matrix and low a_w combination was found to enhance the bacterial stability at the storage temperature of 37 °C. Scanning electron microscopy revealed the formation of corrugated surfaces and blister-type deformations on the cell envelopes during the stabilization process.

Effects of Apricot Fibre on the Physicochemical Characteristics, the Sensory Properties and Bacterial Viability of Nonfat Probiotic Yoghurts

In this study, the physical, chemical, rheological, and microbiological characteristics and the sensory properties of nonfat probiotic yoghurt produced at two different concentrations of apricot fibre (1% and 2%, w/v) and three different types of probiotic culture (Lactobacillus (L.) acidophilus LA-5, Bifidobacterium animalis subsp. lactis BB-12 (Bifidobacterium BB-12), and their mixtures) were investigated. As the fibre content increased, the rheological, structural, and sensory properties of probiotic yoghurt were negatively affected, while counts of L. delbrueckii subsp. bulgaricus, L. acidophilus LA-5, and Bifidobacterium BB-12 increased. When all the results were evaluated, the best results were obtained by using L. acidophilus LA-5 as probiotic culture and adding 1% (w/v) apricot fibre.

Different stress tolerance of spray and freeze dried Lactobacillus casei Shirota microcapsules with different encapsulating agents

In this study, the effects of encapsulation with maltodextrin and reconstituted skim milk (RSM) and their binary and ternary blends with gum arabic (GA) by spray and freeze drying methods on viability of probiotic Lactobacillus casei Shirota under different stress conditions were evaluated. All microcapsules showed high survival ratios (7.91-9.37 log cfu/g) after microencapsulation. The viability of microencapsulated cells was significantly higher than free cells when exposed to stress conditions. Spray dried microcapsules exposed to low pH showed small decrease in the viability of cells compared to freeze dried microcapsules, but freeze drying microcapsules showed higher protective effect at 85 and 90 °C. After exposure to 3% bile salt, almost 2.5 log decreases in the encapsulated cell counts were determined for both methods. The results indicated that using RSM:GA mixture as an encapsulating agent showed the higher cell protection against high temperature, acidic pH and bile salts.

Staying alive: growth and survival of Bifidobacterium animalis subsp. animalis under in vitro and in vivo conditions

Members of the Bifidobacterium genus are widely used as probiotics in fermented milk products. Bifidobacterium animalis subsp. animalis CNCM I-4602 grows and survives poorly in reconstituted skimmed milk (RSM). Availing of genome and transcriptome information, this poor growth and survival phenotype in milk was substantially improved by the addition of certain compounds, such as yeast extract, uric acid, glutathione, cysteine, ferrous sulfate, and a combination of magnesium sulfate and manganese sulfate. Carbohydrate utilization of CNCM I-4602 was also investigated, allowing the identification of several carbohydrate utilization gene clusters, and highlighting this strain's inability to utilize lactose, unlike the type strain of this subspecies, B. animalis subsp. animalis ATCC25527 and the B. animalis subsp. lactis subspecies. In addition, the ability of B. animalis subsp. animalis CNCM I-4602 to colonize a murine model was investigated, which showed that this strain persists in the murine gut for a period of at least 4 weeks. Associated in vivo transcriptome analysis revealed that, among other genes, a gene cluster encoding a predicted type IVb tight adherence (Tad) pilus was upregulated, indicating that this extracellular structure plays a role in the colonization/adaptation of the murine gastrointestinal tract by this strain.

Microencapsulated cells of Lactobacillus paracasei subsp. paracasei in biopolymer complex coacervates and their function in a yogurt matrix

L. paracasei subsp. paracasei E6 cells were encapsulated by complex coacervation using whey protein isolate (WPI) and gum arabic and introduced in stirred yogurts. The encapsulated cells showed improved survival during product cold storage and on exposure to simulated gastric juice.