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Probiotics viability and stability is a core challenge for the food processing industry. To prolong the viability of probiotics (Lactobacillus acidophilus), gelatin (GE)–chitosan (CH) polyelectrolytes‐coated nanoliposomes were developed and characterized. The average particle size of the nanoliposomes was in the range of 131.7–431.6 nm. The mean zeta potential value of the nanoliposomes differed significantly from −42.2 to −9.1 mV. Scanning electron micrographs indicated that the nanoliposomes were well distributed and had a spherical shape with a smooth surface. The Fourier transform infrared spectra revealed that the GE–CH polyelectrolyte coating has been effectively applied on the surface of nanoliposomes and L. acidophilus cells were successfully encapsulated in the lipid‐based nanocarriers. X‐ray diffraction results indicated that nanoliposomes are semicrystalline and GE–CH polyelectrolyte coating had an influence on the crystalline nature of nanoliposomes. Moreover, the coating of L. acidophilus‐loaded nanoliposomes with GE–CH polyelectrolytes significantly improved its viability when exposed to simulated gastrointestinal environments. The findings of the current study indicated that polyelectrolyte‐coated nanoliposomes could be used as an effective carrier for the delivery of probiotics and their application to food matrix for manufacturing functional foods. [ABSTRACT FROM AUTHOR]

Orally delivered probiotics must survive transit through harsh environments during gastrointestinal (GI) digestion and be delivered and released into the target site. The aim of this work was to evaluate the survivability and delivery of gel-encapsulated Lactobacillus rhamnosus GG (LGG) to the colon. New hybrid symbiotic beads alginate/prebiotic pullulan/probiotic LGG were obtained by the extrusion method. The average size of the developed beads was 3401 µm (wet), 921 µm (dry) and the bacterial titer was 109 CFU/g. The morphology of the beads was studied by a scanning electron microscope, demonstrating the structure of the bacterial cellulose shell and loading with probiotics. For the first time, we propose adding an enzymatic extract of feces to an artificial colon fluid, which mimics the total hydrolytic activity of the intestinal microbiota. The beads can be digested by fecalase with cellulase activity, indicating intestinal release. The encapsulation of LGG significantly enhanced their viability under simulated GI conditions. However, the beads, in combination with the prebiotic, provided greater protection of bacteria, enhancing their survival and even increasing cell numbers in the capsules. These data suggest the promising prospects of coencapsulation as an innovative delivery method based on the inclusion of probiotic bacteria in a symbiotic matrix. [ABSTRACT FROM AUTHOR]

This research aims to meet the demand for efficient delivery systems in the food, nutraceutical, and pharmaceutical industries. The study involved the synthesis of starch-based nanoparticles for potential application in the encapsulation of Lactobacillus rhamnosus. Various techniques such as zeta sizer, Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), and scanning electron microscopy (SEM) were used to characterize the encapsulated probiotics in microbeads. The results showed 85.00 % encapsulation efficiency of beads. Microscopic analysis revealed that the probiotics accumulated within the wall material and formed small, smooth polygonal granules on the capsule surface. XRD analysis confirmed the presence of amorphous humps and some crystallinity of nanoparticles in the capsules. Moreover, encapsulation significantly improved probiotic viability under simulated gastrointestinal conditions. This study highlights the potential of starch-based nanoparticles to enhance the stability and viability of probiotics, demonstrating their potential applications across various industrial sectors. Further research should focus on investigating the long-term stability and functional efficacy of encapsulated probiotics in microbeads for real-world applications. [ABSTRACT FROM AUTHOR]

Encapsulation comprises a promising potential for the targeted delivery of entrapped sensitive agents into the food system. A unique combination of cellulose/chitosan (Cl-Ch)-based hybrid wall material was employed to encapsulate L. plantarum by emulsion technique. The developed beads were further subjected to morphological and in vitro studies. The viability of free and encapsulated probiotics was also evaluated in kefir during storage. The developed beads presented porous spherical structures with a rough surface. A 1.58 ± 0.02 log CFU/mL, 1.26 ± 0.01 log CFU/mL, and 1.82 ± 0.01 log CFU/mL reduction were noticed for Cl-Ch hybrid cells under simulated gastro-intestinal and thermal conditions, respectively. The encapsulated cells were found to be acidic and thermally resistant compared to the free cells. Similarly, encapsulated probiotics showed better viability in kefir at the end of the storage period compared to free cells. In short, the newly developed Cl-Ch hybrid-based encapsulation has a promising potential for the targeted delivery of probiotics, as career agents, in gastric transit, and in foods. [ABSTRACT FROM AUTHOR]

The effect that the fructans of Cichorium intybus and Agave salmiana have on health, as well as on the growth of some Lactobacillus species, has been demonstrated. The aim of this work was to evaluate the effect of linear and branched fructans on the growth of seven strains and some probiotic characteristics. The molecular identification of seven strains was performed. Moreover, the growth, resistance to antibiotics and simulated gastrointestinal conditions were also evaluated when these microorganisms were grown in a culture medium containing agave and chicory fructans. The strains were identified as Lactiplantibacillus plantarum, Lactiplantibacillus pentosus, Lactiplantibacillus fabifermentans and Lactiplantibacillus paraplantarum. The results suggest that the seven Lactobacillus strains were able to grow using agave (branched) and chicory (linear) fructans. The linear and branched fructans statistically influenced the kinetic parameters. The specific growth rate varied between 0.270 and 0.573 h−1 and the generation time between 1.21 and 2.45 h for all strains and culture media. All strains showed a growth of 9 Log CFU/mL in all the culture media. Production of lactic, acetic, propionic, butyric, formic and succinic acid was influenced by linear and branched fructans (p < 0.05). All the strains survived simulated gastrointestinal conditions greater than 83%. The resistance of Lactobacillus against ciprofloxacin and rifaximin was significantly affected by linear and branched fructans, but survival to gastrointestinal conditions was not affected by the type of substrate. These results highlight the use of the seven strains, which have probiotic potential; therefore, these could be applied in several biotechnological products. [ABSTRACT FROM AUTHOR]

Encapsulation of low molecular weight (M w) bioactive peptides (BAPs) in electrostatically mediated polyelectrolyte complexes (PECs) of sodium alginate (ALG) and chitosan (CS) was studied, formed via a simple one-step mixing process. PECs were characterized via dynamic light scattering (DLS), mixed-mode phase analysis light scattering (M3-PALS), static light scattering (SLS), small-angle X-ray scattering (SAXS) and transmission electron microscopy (TEM). The encapsulation efficiency (EE) and in vitro release of low M w antihypertensive LKPNM and LKP BAPs (derived from fish hydrolysates) were measured, under both gastric and intestinal pH conditions, via high performance liquid chromatography (HPLC). Two different ALG were tested (M w ≈ 8 and 21 kDa, with mannuronic: guluronic ratios 5.1 and 1.4, respectively), whilst the M w and degree of acetylation (DA) of the CS were ≈111 kDa and ≈10 %, respectively. At the pH (5.5) of PEC formation the BAPs were positively charged. As the molar charge ratio of alginate to chitosan (n−/n+) was increased from 0.1 to 0.6 the PEC size reduced from ca. 800 to 300 ± 50 nm, indicating more compact structures, but increased again significantly to >10 μm around charge neutralisation (n−/n+ = 1) and net PEC ζ-potential swapping from +ve to –ve. The size then decreased again to between 1 and 10 μm as n−/n+ → 10, as expected if the more prevalent polysaccharide (ALG) coated the surface of the PECs. However, higher M w ALG gave significantly smaller (more compact) and more highly negatively charged PECs for n−/n+ > 1. The PECs showed high (≈80%) EE but low (10–20%) release in gastrointestinal conditions, highlighting their potential as effective carriers of such BAPs. [Display omitted] • Bioactive peptides are efficiently encapsulated in alginate + chitosan complexes. • Alginate: chitosan molar charge ratio has a large influence complex size. • Higher M w alginate gives significantly smaller, more compact complexes. • The peptides apparently aid cross-linking of the alginate and chitosan. • Peptide release from complexes at gastrointestinal pH and salt levels was low. [ABSTRACT FROM AUTHOR]

Incorporating probiotic bacteria with different biopolymers as edible films is an effective approach to improve their viability. In this study, three different films (wheat sourdough powder, whole wheat flour, and bovine bone gelatin) are incorporated with Lactobacillus plantarum separately and the viability of bacteria is monitored during the storage time (40 days at 4 °C) and simulated gastrointestinal conditions. The results demonstrated that the sourdough film has the best protective effect on the viability of the cells during the film's preparation, storage time (6.5 Log/CFU/g), and simulated gastrointestinal conditions (7.13 Log/CFU/g). A higher rate of reduction is observed in gelatin film at the end of the storage time (4.03 Log/CFU/g). Physicochemical, and mechanical characteristics are examined. It is observed that the incorporation of bacteria does not affect the thickness, moisture content, and solubility of all films, but changed the mechanical properties of the sourdough and the wheat flour films (p ≤ 0.05). Scanning Electron Microscope images showed a more uniform and compact structure for both bacterial and control gelatin films. Although the sourdough film is appropriate for protecting probiotic bacteria (>106 CFU/g), further studies are needed to improve its mechanical properties. [ABSTRACT FROM AUTHOR]

In the present study, next generation probiotic Akkermansia muciniphila was incorporated into a dairy matrix containing Portuguese whey cheese and Greek-style yoghurt in a proportion of 3.5:1, respectively. Subsequently, this innovative food was characterized in terms of microbiological and physicochemical parameters, total phenolic content and antioxidant, antidiabetic, and antihypertensive activities, as well as its protective effect on A. muciniphila viability during 21 d of refrigerated aerobic storage and when subjected to simulated gastrointestinal passage. The probiotic cheese spread displayed high microbiological quality, low total phenolic content (0.36 mg gallic acid equivalents/g of dried cheese) and interesting biological activities, including antidiabetic (98.10% α-glucosidase inhibition) and antihypertensive (49.18% angiotensin converting enzyme inhibition). Simultaneously, this food ensured a high A. muciniphila viability (>108 CFU/g) during 21 d of refrigerated aerobic storage with subsequent in vitro digestion. Additionally, this probiotic cheese presented a similar profile in terms of texture, color, water activity and pH when compared to the cheese control (without A. muciniphila), suggesting a potentially high acceptance among consumers. In conclusion, the developed cheese spread seems to be a promising and suitable food vector to safeguard A. muciniphila viability during refrigerated aerobic storage for at least 21 d with subsequent gastrointestinal passage. • A. muciniphila was incorporated in a whey cheese and Greek-style yogurt matrix. • Probiotic cheese displayed valuable antidiabetic and antihypertensive activities. • Cheese ensured high A. muciniphila viability during storage and in vitro digestion. • Probiotic addition did not affect texture, color, water activity and pH of cheese. • Whey cheese plus Greek-style yogurt could be a good food vector for A. muciniphila. [ABSTRACT FROM AUTHOR]

Kappa-carrageenan beads thermally protect encapsulated curcumin molecules and release them sustainably during simulated gastrointestinal conditions. [Display omitted] • Curcumin embedded κ-carrageenan hydrogel beads show a high encapsulation efficiency of 74.61 ± 3.2 %. • The beads exhibit sustained and pH-responsive release kinetics, conforming to first-order kinetics in simulated gastric conditions and a two-stage Korsmeyer-Peppas and first-order kinetics in simulated intestinal and aqueous environments. • Sustained release of curcumin over time suggests the potential of κ-carrageenan beads as a suitable delivery system for bioactive components. This study investigates the potential of κ-carrageenan hydrogel beads as a delivery system for curcumin, a bioactive compound with various health benefits. Hydrogel beads were prepared using the extrusion technique with a hypodermic needle. The encapsulation efficiency of curcumin in the κ-carrageenan hydrogel beads was found to be 74.61 ± 3.2 %. FTIR spectroscopy analysis revealed shifts in absorption peaks, indicating possible hydrogen bonding and/or ionic interactions between the polymer and salt. An increase in the melting point of curcumin, by 25 °C, in curcumin- κ-carrageenan beads suggests the heat protection offered by the carrageenan chains to curcumin molecules. The i n vitro release of curcumin from the beads suggests a sustained and pH-dependent release nature. The release kinetics follow the first order and the Korsmeyer-Peppas model. The outcome offers value-added delivery systems of bioactive compounds toward developing novel food and pharmaceutical applications. [ABSTRACT FROM AUTHOR]

Abstract The objectives of this study were to develop a probiotic milk powder containing Lactobacillus plantarum NCIMB 8826 immobilized with prebiotic Hi-maize starch and to analyze cell viability after spray drying and exposure to simulated gastric and intestinal conditions. Milk powders containing free L. plantarum and cells immobilized with Hi-maize starch were assessed. Powders were evaluated during storage at 4 °C for 15 days. After spray drying, at 0 and 15 days of storage both treatments had over 8 log CFU/g of viable cells and there were higher viable counts found for immobilized cells compared to free cells after 120 min in simulated gastric fluid. At 15 days of storage, immobilized cells had higher viable counts than free cells after exposure to simulated intestinal fluid for 120 min. The combined probiotic and prebiotic milk powder had stable viable cell counts at refrigerated storage conditions and under simulated gastric and intestinal transit. Graphical abstract

Encapsulation comprises a promising potential for the targeted delivery of entrapped sensitive agents into the food system. A unique combination of cellulose/chitosan (Cl-Ch)-based hybrid wall material was employed to encapsulate L. plantarum by emulsion technique. The developed beads were further subjected to morphological and in vitro studies. The viability of free and encapsulated probiotics was also evaluated in kefir during storage. The developed beads presented porous spherical structures with a rough surface. A 1.58 ± 0.02 log CFU/mL, 1.26 ± 0.01 log CFU/mL, and 1.82 ± 0.01 log CFU/mL reduction were noticed for Cl-Ch hybrid cells under simulated gastro-intestinal and thermal conditions, respectively. The encapsulated cells were found to be acidic and thermally resistant compared to the free cells. Similarly, encapsulated probiotics showed better viability in kefir at the end of the storage period compared to free cells. In short, the newly developed Cl-Ch hybrid-based encapsulation has a promising potential for the targeted delivery of probiotics, as career agents, in gastric transit, and in foods.

Most foods with probiotics claims are associated to dairy products, whose consumption is restricted to part of the population, creating a favorable scenario for the development of probiotic foods in alternative matrices. However, the development of probiotic foods in non-dairy matrices is still a technological challenge, since the foods intrinsic parameters can cause injuries to microorganisms. An alternative to protect the microbial cells in adverse environments involves encapsulation. Therefore, the objective of this study was to evaluate the influence of alginate-jaboticaba peel blend in the improvement of encapsulation efficiency, viability maintenance, and cell survival of Bifidobacterium BB12® under simulated gastrointestinal digestion and after incorporating in traditional jaboticaba jam. The particles were obtained by ion gelling technique using alginate with or without powdered jaboticaba peel. The addition of jaboticaba peel in particles improved encapsulation efficiency (> 90%) and resulted in higher cell survival in simulated gastrointestinal digestion. During storage in jam, the loss in cell viability was approximately constant: c.a. 0.5 log CFU/g/day for encapsulated cells and c.a. 1.0 log CFU/g/day for free cells. These results suggest that use of alginate and powdered jaboticaba peel blend is a promising approach to protect Bifidobacterium BB12® against adverse environments, such as non-dairy food matrices. Key points: • Powdered jaboticaba peel increased the encapsulation efficiency in alginate particles. • Encapsulation improved cell survival under adverse conditions. • Useful approach for the development of non-conventional probiotic products. Graphical abstract [ABSTRACT FROM AUTHOR]

To protect anthocyanins of Iranian borage extract (IBE) by encapsulation, maltodextrin (MD)/modified maize starch (MMS) combinations were used at four ratios (MD/MMS: 1/0, 1/0.25, 1/0.5, 1/1, w /w%). The microencapsulated powders with different ratios of wall material presented encapsulation efficacy between 93.1 and 97.4%. FTIR confirmed the cross-linking interaction between extract and MD/MMS wall. Increased thermal stability of extract was also indicated by DSC analysis. The stability of microstructures and crude extract at two conditions (5 and 40 °C) was evaluated by UV and HPLC methods during 60 days. The results of stability showed that encapsulation by treatment 4 (MD/MMS 1:1) improved the stability of anthocyanins 43.8% compared to crude extract. Additionally, microcapsule created in this treatment provided great antioxidant stability. The release in the simulated gastrointestinal tract revealed that the anthocyanins were chiefly retained inside the microparticles in the stomach, and were released in the intestine. The results demonstrated that the microencapsulation with MD and MMS by the spray-drying method can improve the stability, antioxidant and functional characteristics of borage extract, which could be useful in the food and pharmaceutical industry. [ABSTRACT FROM AUTHOR]

The main goal of this research was to compare the in vitro release rates of nano- and microcapsules of Silybum marianum extract (SME) in animal simulated gastric and intestinal medium conditions. The extract was encapsulated within sodium alginate carriers using emulsification/internal gelation method. Particle size, zeta potential, polydispersity index (PDI) and morphology of nanocapsules were analysed via dynamic light scattering (DLS) and transmission electron microscopy (TEM). In addition, the effect of ultrasonication on nanocapsule properties and the release profiles of SME-loaded nano/microcapsules were evaluated. Results showed that ultrasonication reduced the size of capsules from 657.5 nm to 169.1 nm which resulted in uniform particles with a low PDI. Encapsulation efficiency for nanocapsules was 61%. Alginate nano/microcapsules protected polyphenols in simulated gastric medium as observed by 10% and 12% release, respectively. Nanocapsules released their contents higher and faster than microcapsules in simulated intestinal fluid (P<0.05). In conclusion, alginate nanocapsules containing SME were made successfully with a release rate of over 90% of extract within simulated intestinal medium which can be used for animal target delivery purposes. [ABSTRACT FROM AUTHOR]

Abstract This study microencapsulated anthocyanin compounds extracted from blueberry (Vaccinium spp.) by spray drying using different inlet air temperatures (120, 140 and 160 °C) and wall materials (maltodextrin DE20 and hi-maize) to evaluate the microcapsule characteristics, stability and behavior under simulated gastrointestinal tract conditions. The encapsulation efficiency, moisture content, water activity, particle size, determination of total monomeric anthocyanins, storage stability, morphology and simulated gastrointestinal conditions were analyzed as responses. The microcapsules produced with different wall materials and different inlet temperatures presented an encapsulation efficiency between 74.40 and 85.22%. The microcapsule which presented the lowest degradation constant (0.0060) and longest half-life (115.47 days) during storage was treatment T3 (9% maltodextrin DE20 and 9% hi-maize) at 140 °C. Treatment T3 also presented more uniform particles, ensuring a better protection and retention of the active material. Microencapsulation was effective in protection during storage and improved the delivery of compounds of interest under the simulated gastrointestinal conditions in comparison to the free extract during all the steps that comprised the simulated gastric system. Graphical abstract Image Highlights • Encapsulation efficiency of anthocyanins compounds was between 74.40 and 85.22%. • Microencapsulation process resulted in losses between 42.36 and 64% of anthocyanins. • T3 treatment at 140 °C showed the highest protection of anthocyanins. • T3 treatment at 140 °C showed lowest degradation constant and longest half-life. • Microencapsulation was effective in the improved delivery of anthocyanins compounds. [ABSTRACT FROM AUTHOR]

Abstract In recent years application of bacteriophages in the reduction of bacterial pathogens that may contaminate the food supply has become of growing interest. The aim of this study was to produce dried macrospheres ensuring viability of bacteriophages during exposure to adverse conditions of the digestive system after storage for an extended period of time. The viability of phages entrapped in mannitol-alginate wet and dried formulations was investigated for up to 4 weeks of storage at room temperature. Phage-loaded beads were exposed to an acidic environment (pH 2.5) of simulated gastric fluid and directly transferred to intestinal medium to dissolve. During the period from 1 to 4 weeks the survival of bacteriophage T4 in dried macrospheres under simulated gastrointestinal conditions revealed only a slight decrease and resulted in a final survival of 5.02 log 10 pfu/ml. The results of this study show that the addition of 0.3 M mannitol may improve phage protection against gastrointestinal conditions and enable a large proportion of bacteriophage T4 to remain active. The potential of the developed technology can be considered in oral application of bacteriophages to reduce intestinal colonization of pathogenic bacteria via prolonged stability of phages in a dry state. Highlights • Mannitol-alginate macrospheres protect phages under gastrointestinal conditions. • A dried formulation showed high stability during long-term storage. • Encapsulated phages can be used to control foodborne pathogens. [ABSTRACT FROM AUTHOR]

Phytate is a potent inhibitor of mineral absorption in humans occurring in plant-based food. Application of lactobacilli that produce phytate-degrading enzymes (phytases) to reduce phytate is an interesting yet a not much explored sector of research. Therefore, phytate dephosphorylation by Lactobacillus plantarum MTCC 1325 was evaluated. Cells at stationary phase showed phytase activity which was maximal at 24 h of growth. Glucose concentration and the type of phosphorous source in the media modulated the enzyme activity. Fermentation of cereal and/or legume flours with the strain resulted in phytate reduction with the highest in sorghum (73%) and the lowest in horse gram (34%). Further, the strain showed tolerance to acid, bile, and simulated gastrointestinal fluid. Significant phytase activity in the presence of simulated gastrointestinal fluids along with the ability to produce phytases post-exposure to simulated gastrointestinal fluids is of interest. To the best of our knowledge, this is the first report on the effect of simulated gastrointestinal fluid on cell-associated phytases of lactobacilli. The results of the investigation indicate that L. plantarum MTCC 1325 could be used as a starter in cereal-legume fermentation and as potential probiotics to achieve phytate hydrolysis in food matrices and also in gastrointestinal tract. [ABSTRACT FROM AUTHOR]

Abstract Probiotics are commonly added to dairy foods, but due to intolerances and allergies associated with dairy consumption there has been a growing interest in alternative delivery systems. Thus, the viability of Lactobacillus plantarum NCIMB 8826 in a non-alcoholic lactic acid fermented apple juice during 15 d of storage at 4 °C when exposed to simulated gastric and intestinal conditions was evaluated. Tests were conducted on apple juice containing free L. plantarum cells or cells that were immobilized on pectin and added to the juice. During fermentation, the viability of free cells decreased to 7.44 log CFU/mL and the immobilized cells increased to 8.05 log CFU/mL. A decline was observed in the pH and °Brix of the juices with free and immobilized cells, while the lactic acid content increased. All samples except for the juice with free cells at 0 d of storage maintained more than 107 viable CFU/mL when exposed to simulated gastric and intestinal conditions. Fermented apple juice containing immobilized cells during 15 d of refrigerated storage can be used as a functional food for consumers desiring non-dairy probiotic beverages. Highlights • Pectin can immobilize Lactobacillus plantarum NCIMB 8826 in apple juice. • Free and immobilized L. plantarum can ferment apple juice. • Immobilization prior to fermentation protects cells in simulated gut conditions. • Storage of fermented juice at 4 °C aids cell viability in simulated gut conditions. [ABSTRACT FROM AUTHOR]

The aim of this study was to evaluate the influence of edible coatings based on linseed mucilage, alginate, and fructooligosaccharide containing Lactobacillus casei LC-01 on the shelf-life of fresh-cut yacon cubes. The cell viability and survival under in vitro gastrointestinal conditions analysis were performed to evaluate the stability of the microorganism. To evaluate the influence of edible coatings on fresh-cut yacon, physicochemical parameters pH, acidity, soluble solids, color, and weight loss were analyzed. Edible coatings were efficient probiotic cells carrier, preserving the number of viable cells at about 8 log CFU g−1. Under simulated gastrointestinal conditions, the reduction in the number of viable cells of the microorganism was on average 2.96 log CFU g−1, indicating the yacon as viable matrix to carrier probiotic bacteria. The edible coatings helped to preserve the physicochemical parameters of the vegetable, reducing the weight loss and darkening, important factors for the commercialization of the product. [ABSTRACT FROM AUTHOR]

Kafirin microparticles have potential as colon-targeted delivery systems because of their ability to protect encapsulated material from digestive processes of the upper gastrointestinal tract (GIT). The aim was to optimize prednisolone loading into kafirin microparticles, and investigate their potential as an oral delivery system. Response surface methodology (RSM) was used to predict the optimal formulation of prednisolone loaded microparticles. Prednisolone release from the microparticles was measured in simulated conditions of the GIT. The RSM models were inadequate for predicting the relationship between starting quantities of kafirin and prednisolone, and prednisolone loading into microparticles. Compared to prednisolone released in the simulated gastric and small intestinal conditions, no additional drug release was observed in simulated colonic conditions. Hence, more insight into factors affecting drug loading into kafirin microparticles is required to improve the robustness of the RSM model. This present method of formulating prednisolone-loaded kafirin microparticles is unlikely to offer clinical benefits over commercially available dosage forms. Nevertheless, the overall amount of prednisolone released from the kafirin microparticles in conditions simulating the human GIT demonstrates their ability to prevent the release of entrapped core material. Further work developing the formulation methods may result in a delivery system that targets the lower GIT. [ABSTRACT FROM AUTHOR]

Phytate is considered an anti-nutrient, because it is not digestible for humans given our lack of phytase activity (PhyA). It has been hypothesized that Lactobacilli may act as carriers of phytate-degrading activity in the gastrointestinal tract. Therefore, the aim of this work was to assess the PhyA of nineteen probiotic bacteria exposed to simulated gastrointestinal fluids. Each culture was inoculated to three different growth media (MRS, MRS-MOPS and MRS-MOPS + AA). Cell-free extracts were used to test for PhyA assay. The highest PhyA ( P < 0.05) was observed in MRS-MOPS, which was higher than MRS (control). A decrease in PhyA was observed in crude enzyme extracts (CEE) after exposure to gastrointestinal fluids. However, PhyA was higher at low gastric pH values. PhyA was greater in CEE obtained from bacteria that were previously exposed to simulated gastrointestinal conditions, than in those that were not exposed. CEE from Lc-L9 and Lc-12A strains showed the highest activities under intestinal conditions; while Lc-7R1 and Ls-B1917 were the highest under gastric conditions. The ability of specific probiotic bacteria to degrade phytate after exposure to simulated gastrointestinal conditions was demonstrated, which suggests that these bacteria may contribute to improve phytate degradation in humans during digestion. [ABSTRACT FROM AUTHOR]

The aim of this study was to evaluate the capability of Lactobacillus reuteri NRRL 14171 and Lactobacillus casei Shirota to remove dietary acrylamide (AA) under simulated gastrointestinal conditions using a dynamic system. The effects of different AA levels or bacteria concentration on toxin removal by Lactobacillus strains were assessed. Thereafter, AA-removing capability of bacteria strains under either fasting or postprandial simulated gastrointestinal conditions was evaluated. Commercial potato chips were analyzed for their AA content, and then used as a food model. Average AA content (34,162 μg/kg) in potato chips exceeded by ca . 34-fold the indicative values recommended by the EU. Toxin removal ability was dependent on AA content and bacterial cell concentration. A reduction on bacterial viability was observed in the food model and at the end of both digestive processes evaluated. However, bacteria survived in enough concentrations to remove part of the toxin (32–73%). Both bacterial strains were able to remove AA under different simulated gastrointestinal conditions, being L. casei Shirota the most effective ( ca. 70% removal). These findings confirmed the risk of potato chips as dietary AA exposure for consumers, and that strains of the genus Lactobacillus could be employed to reduce the bioavailability of dietary AA. [ABSTRACT FROM AUTHOR]

This study considers the influence of exposure to simulated gastrointestinal conditions (saliva, gut, intestine and acidic conditions of the gut) on IgG binding of unmodified allergens and three types of LMW allergoids of Artemisia vulgaris pollen extract obtained by means of potassium cyanate, succinic and maleic anhydride. It also concerns the optimization of a self-developed ELISA assay for comparison of the specific IgG binding of mugwort pollen extract and modified mugwort pollen derivatives. The ELISA was conducted with a mugwort pollen extract coupled to the plate, using the sera from 12 mugwort-pollen allergic patients. The exposure to saliva fluid for 2 min did not influence the IgG binding properties of allergens and allergoids. Exposure of mugwort pollen allergens and LMW allergoids to the acidic conditions of the gut did not dramatically change their IgG binding properties. By exposing mugwort pollen extract and LMW derivatives to the SGF conditions for 1 h, the percent of IgG binding epitopes was reduced to a half of its starting value in the extract and to about 30 % in all the allergoid samples. After prolonged exposure only the carbamyl derivative showed reduced IgG binding. Changes of the IgG binding potential of all four samples after exposure in SIF followed a similar pattern.

This study considers the influence of exposure to simulated gastrointestinal conditions (saliva, gut, intestine and acidic conditions of the gut) on IgG binding of unmodified allergens and three types of LMW allergoids of Artemisia vulgaris pollen extract obtained by means of potassium cyanate succinic and maleic anhydride. It also concerns the optimization of a self-developed ELISA assay for comparison of the specific IgG binding of mugwort pollen extract and modified mugwort pollen derivatives. The ELISA was conducted with a mugwort pollen extract coupled to the plate, using the sera from 12 mugwort- pollen allergic patients. The exposure to saliva fluid for 2 min did not influence the IgG binding properties of allergens and allergoids. Exposure of mugwort pollen allergens and LMW allergoids to the acidic conditions of the gut did not dramatically change their IgG binding properties. By exposing mugwort pollen extract and LMW derivatives to the SGF conditions for 1 h, the percent of IgG binding epitopes was reduced to a half of its starting value in the extract and to about 30%in all the allergoid samples. After prolonged exposure only the carbamyl derivative showed reduced IgG binding. Changes of the IgG binding potential of all four samples after exposure in SIF followed a similar pattern.

Kafirin microparticles have potential as colon-targeted delivery systems because of their ability to protect encapsulated material from digestive processes of the upper gastrointestinal tract (GIT). The aim was to optimize prednisolone loading into kafirin microparticles, and investigate their potential as an oral delivery system. Response surface methodology (RSM) was used to predict the optimal formulation of prednisolone loaded microparticles. Prednisolone release from the microparticles was measured in simulated conditions of the GIT. The RSM models were inadequate for predicting the relationship between starting quantities of kafirin and prednisolone, and prednisolone loading into microparticles. Compared to prednisolone released in the simulated gastric and small intestinal conditions, no additional drug release was observed in simulated colonic conditions. Hence, more insight into factors affecting drug loading into kafirin microparticles is required to improve the robustness of the RSM model. This present method of formulating prednisolone-loaded kafirin microparticles is unlikely to offer clinical benefits over commercially available dosage forms. Nevertheless, the overall amount of prednisolone released from the kafirin microparticles in conditions simulating the human GIT demonstrates their ability to prevent the release of entrapped core material. Further work developing the formulation methods may result in a delivery system that targets the lower GIT.

Bacillus cereus is a Gram-positive bacterium widely distributed in soil and vegetation. This bacterial species can also contaminate raw or processed foods. Pathogenic B. cereus strains can cause a range of infections in humans, as well as food poisoning of an emetic (intoxication) or diarrheal type (toxico-infection). Toxico-infections are due to the action of the Hbl toxin, Nhe toxin, and cytotoxin K produced by the microorganism in the gastrointestinal tract. This occurs once the spores or vegetative B. cereus cells survive the pH barrier of the stomach and reach the small intestine where they produce toxins in sufficient amounts. This article discusses the effect of various factors on the survival of B. cereus in the gastrointestinal tract, including low pH and the presence of digestive enzymes in the stomach, bile salts in the small intestine, and indigenous microflora in the lower parts of the gastrointestinal tract. Additional aspects also reported to affect B. cereus survival and virulence in the gastrointestinal tract include the interaction of the spores and vegetative cells with enterocytes. In vitro studies revealed that both vegetative B. cereus and spores can survive in the gastrointestinal tract suggesting that the biological form of the microorganism may have less influence on the occurrence of the symptoms of infection than was once believed. It is most likely the interaction between the pathogen and enterocytes that is necessary for the diarrheal form of B. cereus food poisoning to develop. The adhesion of B. cereus to the intestinal epithelium allows the bacterium to grow and produce enterotoxins in the proximity of the epithelium. Recent studies suggest that the human intestinal microbiota inhibits the growth of vegetative B. cereus cells considerably. [ABSTRACT FROM AUTHOR]

The protective effects of encapsulation on the survival of Lactobacillus reuteri and the retention of the bacterium's probiotic properties under simulated gastrointestinal conditions were investigated. Viable counts and the remaining probiotic properties of calcium (Ca)-alginate encapsulated (A group), chitosan-Ca-alginate encapsulated (CA group), and unencapsulated, free L. reuteri (F group) were determined. Encapsulation improved the survival of L. reuteri subjected to simulated gastrointestinal conditions, with the greatest protective effect achieved in the CA group. The degree of cell membrane injury increased with increasing bile salt concentrations at constant pH, but the extent of injury was less in the encapsulated than in the free cells. Adherence rates were, in descending order: CA (0.524%) > A (0.360%) > F (0.275%). Lactobacillus reuteri cells retained their antagonistic activity toward Listeria monocytogenes even after incubation of the Iactobacilli under simulated gastrointestinal conditions. Displacement of the pathogen by cells released from either of the encapsulation matrices was higher than that by free cells. The safety of L. reuteri was demonstrated in an in vitro invasion assay. [ABSTRACT FROM AUTHOR]

[Display omitted] • Microalgae biomasses enhanced the probiotic survival during freeze-drying. • Microalgae protection exerted during storage varied with probiotic strain tested. • Microalgae biomasses protected probiotic cultures during in vitro digestion. • Microalgae biomasses reduced probiotic membrane damage during freeze-drying. • Ultrastructural aspects of probiotic cells varied with the microalgae tested. This study aimed to assess Spirulina platensis, Chlorella vulgaris, Scenedesmus quadricauda, and Lagerheimia longiseta microalgae potential as protective agents for probiotic cultures [(Lactobacillus acidophilus (La-05) and Lacticaseibacillus casei (Lc-01)] during freeze-drying, refrigeration storage (4 °C, 120 days), and in vitro simulated gastrointestinal conditions (SGIC). The occurrence of membrane damage and ultrastructural aspects of the cells were also verified. Fructooligosaccharides (FOS) were used as a positive control and saline solution as a negative control. The effects of the cryoprotectants on probiotic survival depended on the tested probiotic culture and microalgae biomass. For La-05, all tested cryoprotectants caused a lower reduction in probiotic counts during the freeze-drying and up to 90 days of storage. S. platensis kept higher probiotic counts during storage, while C. vulgaris protected the probiotic against the SGIC. L. longiseta decreased the probiotic membrane damage, mainly due to the production of exopolysaccharides, which was observed in the scanning electron microscopy (SEM). For Lc-01, all tested cryoprotectants promoted a lower reduction in probiotic counts up to 120 days of storage. FOS and S. quadricauda protected the probiotics during freeze-drying and refrigeration storage, while C. vulgaris protected the probiotic against the SGIC and caused lower membrane damage, mainly due to physical protection observed in SEM. In conclusion, microalgae biomasses exerted similar or better cryoprotectant effects on probiotics than FOS, a recognized cryoprotective agent. [ABSTRACT FROM AUTHOR]

The aim of this study was to evaluate the characteristics of probiotic stirred yoghurt and the survival of free and microencapsulated cells of Lactobacillus acidophilus LA-5 during refrigerated storage. L. acidophilus LA-5 was microencapsulated by ionic gelation and complex coacervation techniques using pectin and whey protein as wall and coating materials, respectively. The survival of probiotics subjected to conditions simulating the passage through the gastrointestinal tract and the sensory acceptance of yoghurts were evaluated after 35 days of refrigerated storage. The yoghurt containing encapsulated L. acidophilus LA-5 showed lower post-acidification and improved probiotics survival (62%) when compared to the yoghurt containing free cells of L. acidophilus LA-5 (10%) after 35 days of refrigerated storage. The encapsulated L. acidophilus LA-5 showed higher survival than the free microorganism during simulated gastrointestinal conditions. After 35 days of storage, no significant difference was observed for the attributes appearance, aroma, flavor, and overall impression for both samples. However, with respect to the attribute texture, the yoghurt containing encapsulated L. acidophilus LA-5 was less accepted than yoghurt containing free cells of L. acidophilus LA-5. Microencapsulation of L. acidophilus LA-5 by ionic gelation and complex coacervation provided lower post-acidification in probiotic yoghurts, and protection to the microorganism, during 35 days of refrigerated storage and during the passage through the simulated gastrointestinal conditions. [ABSTRACT FROM AUTHOR]

In order to protect peroral β-galactosidase from being degraded and hydrolyse milk lactose efficiently in the environments of gastrointestinal tract, a double-capsule delivery system composed of enteric-coated capsule and polylactic acid (PLA) nanocapsules (NCs) was developed for encapsulation of β-galactosidase. β-galactosidase-loaded PLA NCs in the size range of 100–200 nm were prepared by a modified w1/o/w2 technique. During the encapsulation process, dichloromethane/ethyl acetate (1 : 1, v/v) as the solvent composition, high-pressure homogenisation (150 bar, 3 min) as the second emulsification method and polyvinyl alcohol or Poloxamer 188 as a stabiliser in the inner phase could efficiently improve the activity retention of β-galactosidase (>90%). Subsequently, the prepared NCs were freeze-dried and filled in a hydroxypropyl methylcellulose phthalate (HP55)-coated capsule. In vitro results revealed that the HP55-coated capsule remained intact in the simulated gastric fluid and efficiently protected the nested β-galactosidase from acidic denaturation. Under the simulated intestinal condition, the enteric coating dissolved rapidly and released the β-galactosidase-loaded PLA NCs, which exhibited greater stability against enzymatic degradation and higher hydrolysis ratio (∼100%) towards milk lactose than the free β-galactosidase. These results suggest that this double-capsule delivery system represents promising candidate for efficient lactose hydrolysis in the gastrointestinal tract. [ABSTRACT FROM AUTHOR]

Abstract: Various microbial polymers, namely xanthan gum, gellan gum, pullulan gum and jamilan, were tested as a suitable encapsulating material for Lactobacillus plantarum CRL 1815 and Lactobacillus rhamnosus ATCC 53103. Resulting capsules were also studied for their pH and simulated gastrointestinal conditions tolerance. The morphology of the microcapsules was studied using scanning electron microscopy. pH tolerance was tested at pH 2.0, 3.5, 5.0 and 6.5 over a 6h incubation period. Simulated gastrointestinal conditions were assayed with simulated gastric and pancreatic juices and simulated bile over a 24h incubation period. Suspensions of probiotic organisms were used as a control. The results from encapsulation with microbial polymers indicate that mixtures of 1% xanthan gum with 0.75% gellan gum and 1% jamilan with 1% gellan gum were the most suitable for microencapsulation. Results for the pH tolerance tests showed no improvement in the viability of cells in relation to the control, except for pH 2.0 where lactobacilli encapsulated in xanthan:gellan gum (1%:0.75%) prolonged their viability by 6h exposure. Xanthan:gellan gum (1%:0.75%) was the most effective of the encapsulating materials tested in protecting L. plantarum and L. rhamnosus against simulated bile, improving its viability in 1–2logCFU when compared with control. The results of this study suggest that microbial polymers are an interesting source of encapsulating material that should be taken into account for prospective studies of probiotic encapsulation for oral delivery applications. [Copyright &y& Elsevier]

Abstract: Lactobacillus casei was entrapped in beads made with sodium alginate (A), amidated low-methoxyl pectin (P), and blends of A–P (1:2, 1:4, 1:6 ratios) by the extrusion technique. Diameter, sphericity and textural properties of the beads and the survivability of entrapped Lb. casei in yoghurt and in simulated gastrointestinal conditions were determined. Entrapment efficiency of Lb. casei and diameter increased as the proportion of P and the total biopolymers concentration increased. Principal Component Analysis showed that the survivability of Lb. casei in yoghurt, and in simulated gastric juice, was positively correlated with the diameter and all the textural properties of the beads, while survivability after exposure to simulated gastric juice and bile salts was positively correlated with the sphericity of the beads. The beads made with A–P blends in 1:4 and 1:6 ratios provided a significant better protection to the entrapped Lb. casei under all conditions studied. [Copyright &y& Elsevier]

Abstract: Few in vitro screening assays for biological activities of plant extracts consider the potential effect of the gastrointestinal system on orally consumed plant extracts. Crude water and methanol extracts of Tarchonanthus camphoratus (wild camphor) and Agathosma betulina (‘buchu’) were prepared and exposed to simulated gastric fluid and simulated intestinal fluid during dissolution studies to address this aspect. The crude extracts and resulting simulated gastric fluid and simulated intestinal fluid products were screened for antimicrobial activity against Staphylococcus aureus (ATCC 25923), Enterococcus faecalis (ATCC 29212), Escherichia coli (ATCC 25922) and Proteus vulgaris (ATCC 33420). The T. camphoratus crude extract exhibited antimicrobial activity which was reduced after exposure to simulated gastric fluid. After exposure to simulated intestinal fluid no antimicrobial activity was detected, which suggests chemical alteration or degradation of the active compounds. For A. betulina, the crude water extract and simulated gastric fluid product exhibited no antimicrobial activity, while the simulated intestinal fluid product exhibited antimicrobial activity. This suggests activation of antimicrobial constituents during exposure to simulated intestinal fluid. The chemical composition profiles of the crude extracts and products were determined by means of liquid chromatography coupled to an ultraviolet detector (LC-UV) and a mass spectrometer (LC-MS) to qualitatively assess the effect of exposure to simulated gastrointestinal conditions on the chemical composition of the extracts. In many cases, the peak area of compounds decreased after exposure to simulated gastric fluid and simulated intestinal fluid, while the peak area of other compounds increased. Thus, it can be deduced that the antimicrobial activity and chemical composition was altered after exposure to intestinal conditions during dissolution studies. [Copyright &y& Elsevier]

Abstract: Lactobacillus rhamnosus cultured in sweet whey and harvested in the late log phase was entrapped in the inner aqueous phase of a double water-in-oil-in-water emulsion using concentrated sweet whey as emulsifier. The primary and double emulsion droplets showed practically no changes in their morphology and droplet size with aging time. The viability of the entrapped L. rhamnosus in the double emulsion was compared to that of non-entrapped control cells exposed to low pH and bile salt conditions. The viability of the control cells (initial number=6.57±0.3logcfuml−1) decreased significantly under low pH and bile salt conditions, and their survival was 71% and 89%, respectively. The survival of the entrapped cells (initial number=6.74±0.2log cfu ml−1) increased significantly under low pH and bile salt conditions, and their survival was 108% and 128%, respectively. It is concluded that the double emulsion protected L. rhamnosus against simulated gastrointestinal tract conditions. [Copyright &y& Elsevier]

The health benefits of honey as an oral therapeutic agent for the treatment of diarrhoea caused by Shigella sonnei depend on the ability of honey to withstand human gastrointestinal conditions. This study aimed to investigate whether honey could withstand and inhibit the growth of Shigella sonnei under such conditions. We initially evaluated the survival of Shigella sonnei in human simulated gastric conditions (SGC) and simulated intestinal conditions (SIC). This was followed by determination of the susceptibility of Shigella sonnei to Manuka and Talah honey under gastrointestinal conditions. The colony forming units (CFU) of Shigella sonnei and minimum inhibitory concentrations (MICs) of honey were calculated. Shigella sonnei was unable to survive in the acidic environment of the stomach without food matrix and survived only when inoculated with a food source, resulting in 1.5 × 105 ± 0.2 CFU at 60 min and 1.7 × 105 ± 0.3 CFU after 120 min of incubation. In SIC, it survived both with and without food matrix at the same CFU (1.2 × 107 ±0.4) at 60 min and 1.7 × 107 ±0.2 CFU after 120 min of incubation. Growth of Shigella sonnei was not observed in SGC in the presence of either honey at different concentrations without a food source. In the presence of a food source, Manuka honey inhibited the growth of Shigella sonnei at 10% v/v and Talah honey at 20% v/v dilutions in SGC. In SIC, Manuka honey inhibited the growth of Shigella sonnei at 15% and 20% v/v dilutions, whereas Talah honey inhibited Shigella sonnei at 20% and 25% v/v dilutions without and with food sources, respectively. Shigella sonnei can survive in the acidic environment of the stomach if inoculated with a food source. Acidic pH and pepsin had no deleterious effects on the antibacterial capability of honey. However, bile reduced the antibacterial activity of honey in the intestinal environment. • Shigella sonnei was able to survive in the acidic environment of the stomach when inoculated on ground beef. • Both Manuka and Talah honeys inhibited the growth of Shigella sonnei in the gastrointestinal environment. • Antibacterial activity of honey has increased in gastric simulated conditions. • Bile salts and food reduced the antibacterial activity of honey in intestinal simulated environment. [ABSTRACT FROM AUTHOR]

• Alginate-based nanofibers were fabricated by using electrospinning technique. • Lactobacillus paracasei KS-199 was encapsulated within the alginate mats. • Molecular, thermal and morphological analyses confirmed very good encapsulation. • Viability rate of the strain was determined under simulated conditions and kefir. • Viability rate of the strain could be remarkably enhanced by the encapsulation. • In this study, Lactobacillus paracasei KS-199 was encapsulated within alginate-based electrospun nanofiber mats possessing uniform, well-defined, smooth and bead-free structure with an average size of 305 nm in diameter. Enhanced protection ability of the mats was observed in thermal degradation assays (weight loss from 93.4 to 84.5%). Probiotic and in situ viabilities were determined in simulated gastrointestinal and in vitro conditions, respectively, demonstrating that nanoencapsulation of the strain could enhance its survival in simulated gastric juice (the viability rate from 64.1 to 70.8 log cfu/mL) and improved its viability/survival (from 6.65 to 7.38 log cfu/mL) in kefir, respectively. Inoculation of kefir with encapsulated strain did not change the characteristic pseudoplastic flow behavior and viscoelastic nature (being predominantly elastic than viscous; G ′ > G ′′ values) of kefir. Given these results, it is possible to suggest that alginate can be an important tailor-made biopolymer playing an essential role for encapsulation of probiotics with increased viability. [ABSTRACT FROM AUTHOR]

• Encapsulation efficiency of produced capsules was between 93.05% and 98.87%. • Microencapsulation improved the thermal stability of red raspberry anthocyanin (AC). • Treatment H (SPI + AG with 0.05% AC) showed the highest anthocyanin retention value during storage for 60 days at 37 °C. • Microencapsulation improved the delivery of (AC) under simulated gastrointestinal condition. This study involves microencapsulation of anthocyanin extract (AC) from red raspberry using a freeze drying technique involving ultrasonication of soy protein isolate (SPI), gum arabic (AG), and their combination. Analyses included microcapsule properties, encapsulation efficiency, antioxidant capacity using the DPPH assay, Fourier-transform infrared spectroscopy (FTIR), color, thermal stability, stability during storage, morphology, and simulated gastrointestinal conditions. Encapsulation efficiency (EE) ranged from 93.05% to 98.87% for all microcapsules. The morphology of microcapsules by scanning electron microscopy (SEM) indicated a broken glass shape, with mean size of microcapsules ranging from 21.07 ± 2.71 μm to 48.19 ± 2.33 μm using Mastersizer analyzer. A good relationship obtained between zeta potential (ZP) and FTIR spectrum indicated that there is a chemical cross linking interaction between wall material and core material. All microcapsules enhanced the thermal stability of AC in the temperature range 80–114 °C. Furthermore, AC retention (up to 48%) during storage at 37 °C for 60 days revealed that treatment H combination of SPI and AG was best. In addition, SPI and AG combination presented good release behavior under simulated gastrointestinal conditions compared with unencapsulated anthocyanin. [ABSTRACT FROM AUTHOR]