Simulated Gastrointestinal Conditions Research Articles

A protectant for Lactobacillus rhamnosus based on whey protein isolate and isomalt: Stress resistance and underlying mechanisms

Probiotics are exposed to a variety of abiotic and biotic stresses during food fermentation and production, such as acidity, heat, osmolality, and oxidation, which affect their metabolic activity and efficiency. Therefore, it is essential to develop new protective agents to maintain the activity and stability of probiotics. This study introduces a new protectant, spray-dried whey protein isolate (WPI) and isomaltose (ISO). We evaluated the effects of four WPI-ISO ratios (1:0, 2:1, 1:1, 1:2) on the physical properties, including moisture content, water activity (aw), wettability, and glass transition temperature. In addition, we evaluated the environmental tolerance of Lactobacillus rhamnosus to different WPI-ISO ratios under thermal, storage, and simulated gastrointestinal conditions. The results showed that the moisture content (< 7 %) and water activity (< 0.3) of the protectant and probiotic powders met storage stability requirements. The moisture content, water activity, wettability index (WI), and glass transition temperature decreased significantly with the addition of isomalt, thereby improving the pressure resistance of L. rhamnosus through the synergistic effect of WPI and ISO. The WPI-ISO protectant not only improved the environmental tolerance and wettability of probiotics by reducing the moisture content and water activity but also significantly improved the survival rate of L. rhamnosus under various stress conditions such as high temperature and gastrointestinal environment. L. rhamnosus maintains good activity with a viable bacterial count of over 9 lg CFU/g after 90 days of storage, demonstrating effective protection against the environment stress. This study provides a promising new strategy to improve the stability of probiotics in the food industry.

Optimization and evaluation of a chitosan-coated PLGA nanocarrier for mucosal delivery of Porphyromonas gingivalis antigens

Recent advances in understanding Alzheimer's disease (AD) suggest the possibility of an infectious etiology, with Porphyromonas gingivalis emerging as a prime suspect in contributing to AD. P. gingivalis may invade systemic circulation via weakened oral/intestinal barriers and then cross the blood-brain barrier (BBB), reaching the brain and precipitating AD pathology. Based on the proposed links between P. gingivalis and AD, a prospective approach is the development of an oral nanovaccine containing P. gingivalis antigens for mucosal delivery. Targeting the gut-associated lymphoid tissue (GALT), the nanovaccine may elicit both mucosal and systemic immunity, thereby hampering P. gingivalis ability to breach the oral/intestinal barriers and the BBB, respectively.The present study describes the optimization, characterization, and in vitro evaluation of a candidate chitosan-coated poly(lactic-co-glycolic acid) (PLGA-CS) nanovaccine containing a P. gingivalis antigen extract. The nanocarrier was prepared using the double emulsion solvent evaporation method and optimized for selected experimental factors, e.g. PLGA amount, surfactant concentration, w1/o phase ratio, applying a d-optimal statistical design to target the desired physicochemical criteria for its intended application. After nanocarrier optimization, the nanovaccine was characterized in terms of particle size, polydispersity index (PdI), ζ-potential, encapsulation efficiency (EE), drug loading (DL), morphology, and in vitro release profile, as well as for mucoadhesivity, stability under simulated gastrointestinal conditions, antigen integrity, in vitro cytotoxicity and uptake using THP-1 macrophages.The candidate PLGA-CS nanovaccine demonstrated appropriate physicochemical, mucoadhesive, and antigen release properties for oral delivery, along with acceptable levels of EE (55.3 ± 3.5 %) and DL (1.84 ± 0.12 %). The integrity of the encapsulated antigens remained uncompromised throughout NPs production and simulated gastrointestinal exposure, as confirmed by SDS-PAGE and Western blotting analyses. Furthermore, the nanovaccine showed effective in vitro uptake, while exhibiting low cytotoxicity. Taken together, these findings underscore the potential of PLGA-CS NPs as carriers for adequate antigen mucosal delivery, paving the way for further investigations into their applicability as vaccine candidates against P. gingivalis.

In Vitro evaluation of probiotic properties of lactic acid bacteria strains isolated from juçara fruit native to the Atlantic Forest

Lactic acid bacteria (LAB) are the microorganisms most commonly used as probiotics. Since probiotic benefits are strain-dependent, there is a continuous need for research into new cultures with probiotic properties. Fruits such as juçara (Euterpe edulis Martius), a palm species from the Atlantic Forest threatened with extinction, are rich niches for microorganisms, including LAB. This study investigated the probiotic properties of Lactococcus lactis J7 and Leuconostoc pseudomesenteroides JF17 strains isolated from juçara fruits native to the Atlantic Forest. Probiotic characteristics, such as tolerance to simulated gastrointestinal fluids or juices, hydrophobicity, autoaggregation, coaggregation properties, inhibition of pathogenic microorganisms, and technological properties were evaluated. The survival rate of L. lactis J7 and L. pseudomesenteroides JF17 decreased after exposure to simulated gastrointestinal conditions; however, L. lactis J7 was more resistant, maintaining viability at the end of the enteric phase of 6.07 ± 0.16 log CFU mL-1. The J7 strain also exhibited the highest values in hydrophobicity (12.55 ± 0.52%), autoaggregation (25.63 ± 0.75%), and coaggregation capacity with E. coli ATCC 25922 (21.52 ± 0.98%) and S. Enteritidis ATCC 13076 (22.68 ± 1.01%). Both J7 and JF17 strains demonstrated antimicrobial activity, confirmed by the multilayer agar plate system. Additionally, the growth of the strains was temperature-dependent, and they were able to thrive in high concentrations of sodium chloride (6%). Thus, L. lactis J7 is a promising probiotic candidate for the development of functional products. Nevertheless, further studies using animal models are necessary to explore the properties of these probiotic bacteria. Novel strains isolated from fruits should be studied to broaden the application of probiotic microorganisms in the development of foods and medicines.

Enlarging effects of microplastics on adsorption, desorption and bioaccessibility of chlorinated organophosphorus flame retardants in landfill soil particle-size fractions

Chlorinated organophosphorus flame retardants (Cl-OPFRs) and microplastics (MPs) are emerging pollutants in landfills, but their synergistic behaviors and triggering risks were rarely focused on, impeding the resource utilization of landfill soils. This study systematically investigated the adsorption/desorption behaviors, bioaccessibility and human health risks of Cl-OPFRs in landfill soil particle-size fractions coexisted with MPs under simulated gastrointestinal conditions. The results showed that the adsorption capacity and bioaccessibility of Cl-OPFRs in humus soil were higher than that in subsoil. MPs promoted the adsorption of tris(1-chloro-2-methylethyl) phosphate (TCPP) and tris(1,3-dichloro-2-propyl) phosphate (TDCPP) in landfill soils by up to 34.6 % and 34.1 % respectively, but inhibited the adsorption of tris(2-chloroethyl) phosphate (TCEP) by up to 43.6 %. The bioaccessibility of Cl-OPFRs in landfill soils was positively correlated with MPs addition ratio but negatively correlated with the KOW of Cl-OPFRs, soil organic matter and particle size. MPs addition increased the residual concentration of Cl-OPFRs and significantly increased the bioaccessibility of TCEP and TDCPP by up to 33.1 % in landfill soils, resulting in higher carcinogenic and noncarcinogenic risks. The study presents the first series of the combined behavior and effects of MPs and Cl-OPFRs in landfill soils, and provides a theoretical reference for landfill risk management.

Adsorption of bile salts onto crystalline ritonavir particles under simulated gastrointestinal conditions

The formation of a biomolecular corona on nanoparticles in blood is a well-known phenomenon influencing in vivo performance. Analogous phenomena in other biological fluids, such as the formation of a gastrointestinal (GI) corona, remain under-investigated. The ingestion of medicines leads to the generation of drug particles in the GI fluids. Consequently, an understanding of the behavior of drug particles in the gut requires determination of the adsorption of bile components onto these drug particles. This work aims to elucidate the factors affecting adsorption of bile salts onto ritonavir (RTV) particles. Crystalline RTV particles were incubated with non-micellar or micellar bile salts and bile salt depletion from solution was measured using HPLC and small angle X-ray scattering (SAXS). HPLC results show that bile salts adsorb onto RTV particles, with greater adsorption observed for more hydrophobic bile salts, following the order sodium glycodeoxycholate (SGDC)>sodium taurodeoxycholate (STDC)>sodium glycochenodeoxycholate SGCDC>sodium glycocholate (SGC)>sodium taurocholate (STC). Increasing the ionic strength of the solution led to increased adsorption of STDC, where buffer containing 300 mM NaCl resulted in greater adsorption than 150 mM NaCl. Additionally, micellar bile salts showed greater affinity for RTV particles than unimeric bile salts. In contrast, the extent of bile salt depletion was unaltered by addition of phospholipid to form mixed micelles. SAXS analysis of mixed micelles after incubation with RTV particles confirms depletion of bile salt from the supernatant, evidenced by reduced intensity of the micellar scattering feature. In conclusion, this study investigated factors influencing bile salt adsorption onto drug particles, highlighting the need to consider adsorption of bile components in forming the GI-corona.

Viability and stability evaluation of microencapsulated Lactobacillus reuteri in polysaccharide-based bionanocomposite

Microencapsulation is one of the most important methods to enhance the survival of bacteria when exposed to various harsh conditions. The present study evaluated the viability of L. reuteri ATCC 23272 microencapsulated in polysaccharide-based bionanocomposite. Inulin, polydextrose, and pectin were utilized as prebiotics, and magnesium oxide nanoparticles (MgO NPs) as reinforcing agent in the microgel structure. The composition of bionanocomposite was optimized using the simplex-lattice mixture method. Bionanocomposite optimal formulation was achieved by combining 91.6 % inulin and 8.4 % pectin in the presence of MgO NPs. L. reuteri prebiotic score (1.33) and E. coli (1.08), extrusion efficiency (97.57 %), viability after drying (99.37 %), and viability in simulated gastrointestinal conditions (SGI) (91.74 %) were obtained. Not using MgO NPs in the optimal composite structure caused a decrease of 2.14 log CFU/g in SGI. During 28 days of storage of bacteria at 4 and 25 °C, respectively, a reduction of 2.56 and 3.04 log CFU/g was observed for free cells compared to encapsulated cells. SEM, FTIR, and XRD analyses were performed on ingredients and microcapsules with and without bacteria. The results exhibited that the optimal bionanocomposite could be used as a beneficial encapsulation system to improve the performance of probiotics in harsh conditions.

Formulation, Characterization, and In Vitro Simulated Gastrointestinal Fluid Analysis of Chewable Yogurt Tablet Incorporated with Corncob Fiber

This study formulates and evaluates a novel functional food, corncob fiber-infused chewable yogurt tablets, to enhance nutritional value. The tablets have the potential to alleviate gastrointestinal symptoms in the elderly and combat malnutrition in selective eaters, potentially replacing multiple supplement tablets. Four batches of tablets underwent rigorous evaluation, considering physicochemical properties, shelf life, and probiotic viability in simulated gastrointestinal conditions. All tablets exhibited robust stability against simulated fluids (85–90% survival rate) and met desired physicochemical benchmarks. Notably, F1 had the lowest hardness (9.50 kp/cm&lt;sup&gt;²&lt;/sup&gt;), while tensile strength showed no significant variance (0.93–1.18 N/mm&lt;sup&gt;²&lt;/sup&gt;) between tablets. However, F3 and F4 displayed significantly longer disintegration times (41.11–52.82 min). After three months, the average bacterial viability was 7 log no. CFU/g, highlighting the tablets’ potential to deliver intact probiotics for immediate beneficial effects upon consumption. Thus, these chewable yogurt tablets offer a promising means to deliver probiotics effectively while addressing specific dietary challenges.

Physiological and Technological Properties of Probiotic Lacticaseibacillus rhamnosus GG Encapsulated with Alginate-Chitosan Mixture and Its Incorporation in Whole Milk.

This study developed and evaluated chitosan-sodium alginate capsules containing the probiotic Lacticaseibacillus rhamnosus GG using extrusion and emulsification techniques. The encapsulated L. rhamnosus GG cells were also evaluated for technological and probiotic-related physiological functionalities, as well as when incorporated in UHT and powdered milk. Extrusion (86.01 ± 1.26%) and emulsification (74.43 ± 1.41%) encapsulation techniques showed high encapsulation efficiency and high survival rates of L. rhamnosus GG during 28days of refrigeration and room temperature storage, especially emulsification capsules (> 81%). The encapsulated L. rhamnosus GG cells showed high survival rates during exposure to simulated gastrointestinal conditions (72.65 ± 1.09-114.15 ± 0.44%). L. rhamnosus GG encapsulated by extrusion and emulsification performed satisfactorily in probiotic-related physiological (pH and bile salts tolerance) and technological properties (positive proteolytic activity, diacetyl and exopolysaccharides production, high NaCl tolerance (> 91%), besides having high heat tolerance (> 76%)). L. rhamnosus GG in extrusion and emulsification capsules had high survival rates (> 89%) and did not significantly affect physicochemical parameters in Ultra-High Temperature (UHT) and powdered milk during storage. The results demonstrate that L. rhamnosus GG can be successfully encapsulated with alginate-chitosan as a protective material through extrusion and emulsification techniques. UHT and powdered milk could serve as appropriate delivery systems to increase the intake of this encapsulated probiotic by consumers.

Bacillus spp. Isolated from Miang as Potential Probiotics in Nile Tilapia Culture-In Vitro Research.

Among 79 Bacillus spp. isolated from Miang, a fermented tea in north Thailand, 17 Bacillus strains were selected with probiotic potential in Nile tilapia culture based on the capabilities of bacteriocin production and associated antimicrobial activities against fish pathogens, Aeromonas hydrophila and Streptococcus agalactiae. However, only six isolates were selected for further extensive studies based on the strength of their antimicrobial activities and their tolerance against simulated gastrointestinal conditions. The molecular identification by 16S rRNA gene sequence analysis revealed that five isolates, K2.1, K6.1, K7.1, K15.4, and K22.6, were Bacillus tequilensis, and the isolate K29.2 was Bacillus siamensis. B. siamensis K29.2 showed complete susceptibility to antibiotics tested in this study, while B. tequilensis K 15.4 showed moderate resistance to some antibiotics; therefore, both strains were selected as potential probiotic bacteria. B. tequilensis K15.4 and B. siamensis K29.2 were capable of the production and secretion of extracellular protease and polysaccharide degrading enzymes, including cellulase, xylanase, and β-mannanase. The tannin tolerant test also demonstrated their ability to grow on selective agar plates and secrete cellulase and β-mannanase in the presence of hydrolyzable tannin. In addition, in vitro digestion of commercial fish substrate revealed that the extracellular enzymes produced by both strains efficiently reacted with feed protein and polysaccharides. Based on the results from this study, B. siamensis K29.2 was deemed to have the highest potential multifunctional probiotic qualities for application in Nile tilapia culture, while the antibiotic-resistant gene in B. tequilensis K15.4 must be clarified before field application.

Preparation, characterization and microencapsulation of walnut (Juglans regia L.) peptides-zinc chelate.

In this research, a novel kind of walnut (Juglans regia L.) peptides-zinc (Zn-WPs) chelate was obtained using the mass ratio of the walnut peptides (WPs) to ZnSO4.7H2O of 3.5:1 at pH 8.5 and 50°C for 84min, with the chelation rate of 84.5%. In comparison to walnut peptides (WPs), the contents of aspartic acid and glutamic acid in Zn-WPs chelate are approximately 27%, indicating that hydrophilic amino acids predominantly bind with walnut peptides. Following chelation with zinc ions, the ultraviolet-visible (UV) characteristic absorption peak shifted from 213nm to 210nm, while the average particle size of the chelate increased to 8.0±0.14µm, presenting a loose spherical structure under scanning electron microscopy. These findings suggest the formation of new substances. Fourier-transform infrared spectroscopy (FTIR) revealed carboxyl, amino, and peptide bonds as the chelation sites of WPs and zinc. The IC50 of walnut peptides-zinc (Zn-WPs) chelate is 2.91mg/mL, indicative of a favorable DPPH radical scavenging rate. Furthermore, Zn-WPs chelate microcapsules were produced via the spray drying method, achieving an encapsulation rate of 75.67±0.83% under optimal conditions. These microcapsules demonstrate robust stability across diverse environmental conditions. This study underscores the potential of Zn-WPs and its chelate microcapsules to enhance stability and bioactivity under varying circumstances. PRACTICAL APPLICATION: In this study, a new walnut peptide-zinc (Zn-WPs) chelate was prepared. The presence of zinc ions changes the structure and properties of walnut peptides and improves its stability. The production of Zn-WPs chelate microcapsules enables Zn-WPs to have strong in vitro stability under different pH and simulated gastrointestinal digestion conditions. These results provide novel insights for developing the walnut peptides as bioactive ingredients in functional foods.

Date yogurt supplemented with Lactobacillus rhamnosus (ATCC 53103) encapsulated in wild sage (Salvia macrosiphon) mucilage and sodium alginate by extrusion: The survival and viability against the gastrointestinal condition, cold storage, heat, and salt with low pH.

The efficacy of probiotics in providing health benefits may be related to their ability to survive at a sufficient concentration of 106 CFU/g during storage in food and colonization in the gastrointestinal tract. Microencapsulation is a viable method to improve the survivability of probiotics under harsh environmental conditions. In this research, microencapsulated Lactobacillus rhamnosus (MLR) was produced by a two-layer extrusion technique with sodium alginate and wild sage (Salvia macrosiphon) mucilage (SMM) in varying concentrations ranging from 0.2% to 0.8% as the first and second wall materials, respectively. The microencapsulation efficiency and second layer diameter of beads increased significantly with the increase in SMM concentrations. Microencapsulated Lactobacillus rhamnosus (LR) maintained its minimal concentration (6 log CFU/g) during 9 min at 72°C. The MLR-date yogurt (DY) sample had the lowest pH, highest acidity, and highest survival rate among the others at the end of storage. In simulated gastrointestinal conditions (SGC), the survival rates of free LR (FLR) and MLR were 45% and 47% on the 14th day of storage, respectively. In sensory properties, MLR had the highest score in odor and texture parameters but not in others. The MLR viscosity (666.3 mPa·s-1) and SEM images show a relatively denser structure for MLR. In conclusion, this study emphasized the potential of using double-layered beads to protect probiotics, providing valuable inspiration for developing new functional foods with higher survival ability in harsh conditions.

Formulation optimization of a probiotic low-calorie chocolate milk and investigating its qualitative properties during storage

Due to concern regarding the consumption of high amount of sugar in diet and role of diet in combating overweigh and related disease, the aim of present study was to optimize a reduced calorie probiotic chocolate milk formula with suitable physicochemical properties. The formula comprising inulin, stevia (Stevia rebaudiana Bertoni), chia (Salvia hispanica L.) seed gum (CSG), and whey protein concentrate (WPC) which optimized using Box-Behnken design (BBD) and then enriched with an encapsulated probiotic strain Lactobacillus acidophilus (DSM1643). The independent variables included inulin (2–8%), CSG (0.1–0.5 %), stevia (50–100 % replacement of sugar), and WPC (1–3%). The dependent variables were selected as viscosity, average particle size, sedimentation percentage, and general acceptance. Optimization done toward achieving the highest viscosity and general acceptance and the lowest sedimentation percentage and average particle size. The optimal conditions were found to be 7.99 % inulin, 70 % stevia, 0.34 % CSG, and 1 % WPC. Under these conditions, the viscosity, sedimentation percentage, average particle size, and general acceptance of the product were equal to 40.69 mPa s, 2.2 %, 434.221 nm, and 5.1, respectively. Next, the chocolate milk was enriched with at 109 CFU/g probiotic bacteria and evaluated. The probiotic strain was resistant to simulated gastrointestinal conditions and under this condition the free bacterial cells count declined by 8 logCFU/g while the encapsulated cells decreased approximate 3 logCFU/g. The bacteria count did not undergo a significant change until the 5th day of storage. The results showed that the inulin, stevia, CSG, and WPC at optimal concentrations and encapsulated probiotic bacteria could be simultaneously applied to produce a product with good properties. This formula could be considered as a new product with health improving properties, low calorie which is suitable for people suffering from diabetes and obesity.

Lactobacillus rhamnosus GG coating with nanocomposite ameliorates intestinal inflammation

The steady increase in the prevalence of inflammatory bowel disease (IBD) is regarded as a worldwide health issue. Gut microorganisms could modulate host immune and metabolic status and are associated with health effects. Probiotics, Lactobacillus rhamnosus GG (LGG), are beneficial microorganisms that ameliorate disease and exert advantageous effects on intestinal homeostasis. However, the viability of probiotics will suffer from various risk factors in the digestive tract. In this view, we developed a probiotic coating with nanocomposite using tannic acid (TA) and casein phosphopeptide (CPP) through layer-by-layer technology to overcome the challenges after oral administration. LGG showed an improved survival rate in simulated gastrointestinal conditions after coated. The coating (LGG/TA-Mg2+/CPP) had potent reactive oxygen species (ROS) scavenging ability and improved the survival rate of colorectal epithelial cells after H2O2 stimulation. In DSS-induced colitis, administration of LGG/TA-Mg2+/CPP ameliorated intestinal inflammation and reduced the disruption of barrier function. Furthermore, LGG/TA-Mg2+/CPP increased the abundance and diversity of the gut microbiota. In the mouse model of DSS colitis, LGG/TA-Mg2+/CPP can better activate the EGFR/AKT signaling pathway, thereby protecting the epithelial barrier function of the colon epithelium. In conclusion, the probiotic coating with nanocomposite may become a delivery platform for probiotics applied to IBD.

Microencapsulation of Lactobacillus sakei and Lactobacillus rhamnosus in whey protein isolate and sodium hyaluronate for potential food-grade probiotic delivery system

In this study, dairy protein (whey protein isolate, WPI) and dairy ingredients (sodium hyaluronate, SH) were selected as candidates for probiotic encapsulation, directly useable as starters for dairy products. The effects of different weight ratios of WPI and SH (1:0, 3:1, 1:1, 1:3, and 0:1) on the encapsulation of two probiotic strains were investigated. Characteristic properties and survival ability under low pH, bile salts, simulated gastrointestinal conditions, high temperatures, and freezing temperatures were determined. The highest encapsulation rates of Lb. sakei and Lb. rhamnosus were 98.48% and 86.59%, respectively. Differential Scanning Calorimetry (DSC) and Fourier Transform Infrared (FTIR) spectroscopy results showed that the interaction between WPI and SH via hydrophobic and hydrogen bonding increased thermal stability. Compared to free bacterial cells, the survival rate significantly increased at pH 2.0. Under simulated gastrointestinal conditions, Lb. sakei J15 was achieved the best protection with a with a 45.39% survival rate at a WPI:SH ratio of 3:1, whereas Lb. rhamnosus S8 also had a survival rate of 62.96% at the same ratio. At the highest experimental temperature (70 °C), Lb. sakei J15 had the highest survival rate of 31.95% at a WPI:SH ratio of 1:3, whereas Lb. rhamnosus S8 exhibited a 20.55% survival rate at the WPI:SH ratio of 3:1. Although different ratios exhibited varying properties, a WPI:SH ratio of 3:1 was the most effective for maintaining bacterial viability under external environmental conditions. These findings demonstrate a new probiotic delivery system and provide insights into the underlying mechanisms of complex formation and bacterial survival.

Characterization of pectin-zein nanoparticles encapsulating tanshinone: Antioxidant activity, controlled release properties, physicochemical stability to environmental stresses

Tanshinone compounds, natural antioxidants found in the roots of Salvia subg Perovskia plants, offer various health benefits and can serve as natural food additives, replacing synthetic antioxidants. In this study, the nanoparticles were created using the antisolvent method, which were then evaluated for their antioxidant and antibacterial properties, as well as their ability to release tanshinone and withstand environmental stress. The results of the study demonstrated a significant improvement in the antioxidant capabilities of tanshinone with the nanoparticle coating. The T/Z/P NPs exhibited enhanced tanshinone release under simulated gastrointestinal conditions compared to T/Z nanoparticles. These nanoparticles displayed remarkable stability against fluctuations in environmental pH and thermal conditions. The study also revealed that the critical flocculation concentration of the system was 0.5 M of salt. Furthermore, the T/Z/P NPs showed good stability during storage at 4°C for 30 days, making them an excellent candidate for use in various food products.

Whole genome sequence analysis and in vitro probiotic characteristics of Lactococcus lactis ZFM559

Lactococcus lactis, a candidate probiotic, is extensively applied in the fermentation of the food industry and is recognized for its potential to enhance human health. In this study, L. lactis ZFM559, which exhibits probiotic properties, was isolated from fresh milk. In vitro assays have demonstrated it has the ability to inhibit and co-aggregate with multiple pathogenic strains, as well as good tolerance to high osmotic pressure (10% NaCl), low pH (3.0), and simulated gastrointestinal conditions. Moreover, L. lactis ZFM559 is capable of producing folate and inhibiting α-glucosidase activity. Whole-genome sequencing has revealed the components of its genome, which include one circular chromosome and three linear plasmids. Functional annotation of the genome has identified the pathway for γ-aminobutyric acid synthesis, genes and enzymes associated with flavor production and lactose decomposition, and proteins related to environmental stress tolerance. Additionally, a complete gene cluster (including LanT, HlyD, LcnB, and GlyS) for the synthesis of bacteriocins was identified. In summary, L. lactis ZFM559 can be considered a probiotic with significant potential for applications in the food industry and human health.

Survivability of probiotic under simulated gastrointestinal conditions as affected by synbiotic (alginate-arabinoxylan) encapsulation

ABSTRACT The food industry is faced with a significant challenge in maintaining the viability and stability of probiotics during processing and in model food. Encapsulation technology offers a promising solution to this issue. This study was aimed to investigate the effect of Sodium Alginate (SA) and arabinoxylan (AX) composite encapsulation on the viability & stability of Lactobacillus rhamnosus GG. The AX was extracted from maize and characterized, and then the SA-AX composite was used to encapsulate the probiotics. The resulting microbeads were analyzed for their morphological, molecular, and physicochemical properties. The MAX-SA microbeads demonstrated the highest efficiency at 97.9 ± 0.6%, followed by MAX at 95 ± 1.5% and SA at 92 ± 1.4%. The FTIR spectra revealed specific functional groups in the samples. The MAX-SA and MSA matrices had a dispersed structure, while the MAX matrix had a smooth microstructure. The microcapsules had an average size ranging from 718 ± 2 mm to 734 ± 2 mm. The viability of the encapsulated probiotics was assessed under storage conditions, simulated gastrointestinal conditions, and model food. Encapsulated probiotics showed higher viability than free probiotics in simulated gastrointestinal conditions, and pineapple juice fortified with encapsulated probiotics showed a higher probiotic count. Overall, the study found that MAX-SA was the most effective in maintaining probiotic viability under stressed conditions.

Effect of gastrointestinal resistant encapsulate matrix on spray dried microencapsulated Lacticaseibacillus rhamnosus GG powder and its characterization

This study investigated spray drying a method for microencapsulating Lacticaseibacillus rhamnosus GG using a gastrointestinal resistant composite matrix. An encapsulate composite matrix comprising green banana flour (GBF) blended with maltodextrin (MD) and gum arabic (GA). The morphology of resulted microcapsules revealed a near-spherical shape with slight dents and no surface cracks. Encapsulation efficiency and product yield varied significantly among the spray-dried microencapsulated probiotic powder samples (SMPPs). The formulation with the highest GBF concentration (FIV) exhibited maximum post-drying L. rhamnosus GG viability (12.57 ± 0.03 CFU/g) and best survivability during simulated gastrointestinal digestion (9.37 ± 0.05 CFU/g). Additionally, glass transition temperature (Tg) analysis indicated good thermal stability of SMPPs (69.3 – 92.9 ℃), while Fourier Transform infrared (FTIR) spectroscopy confirmed the structural integrity of functional groups within microcapsules. The SMPPs characterization also revealed significant variation in moisture content, water activity, viscosity, and particle size. Moreover, SMPPs exhibited differences in total phenolic and flavonoid, along with antioxidant activity and color values throughout the study. These results suggested that increasing GBF concentration within the encapsulating matrix, while reducing the amount of other composite materials, may offer enhanced protection to L. rhamnosus GG during simulated gastrointestinal conditions, likely due to the gastrointestinal resistance properties of GBF.

Assessment of Phenolic Compound Bioaccessibility in Yerba Mate-Supplemented Bread via in vitro Gastrointestinal Simulation

ABSTRACT This research investigated how incorporating yerba mate (YM) affects whole grain bread’s phenolic profile and in vitro antioxidant activity following simulated gastrointestinal conditions. Three samples were prepared: BWWF (control), B1, and B2 (2.5 and 4.5% YM, respectively). Some phenolic compounds in breads, such as chlorogenic, benzoic, syringic, p-coumaric, and syringaldehyde acid, showed bioaccessible potential since they appeared during the three phases of gastrointestinal digestion. In the gastric phase the compounds present, ferulic acid (bread WWF) was the major compound with 6960 µg/g, for bread with 2.5% YM and bread with 4.5% YM was rutin and chlorogenic acid with 14,945 µg/g and 7881 µg/g, respectively. In the intestinal phase, there was a significant reduction in the levels of phenolic compounds. Bioaccessibility was influenced by the addition of YM, indicating that including this plant in food could add value to this regional product.

Lactiplantibacillus plantarum ACCC 11095 microencapsulated by lotus seeds cross-linked resistant starch: Survival under simulated gastrointestinal conditions and its structural changes

Under simulated gastrointestinal digestion, we investigated the protective and releasing effects of lotus seed cross-linked resistant starch (LSCS) with low, medium, and high cross-linking degree toward Lactiplantibacillus plantarum ACCC 11095 and associated structural changes. Probiotic microcapsules (PM) made of high crosslinking starch showed better encapsulation rates (48.81%) and released 6.26 log CFU/g of viable bacteria after digestion, which helped colonize and exert probiotic effects in the intestinal tract. Scanning electron microscopy and Fourier Transform Infrared spectroscopy confirmed better high crosslinking starch protection for probiotic bacteria. This was closely related to PM embedded materials. Correlation analysis showed that agglomeration between high crosslinking starch starch granules in PM was significantly enhanced, and amorphous zones were hydrolyzed to a lesser extent, providing better Lactiplantibacillus plantarum ACCC 11095 protection. Thus, high crosslinking starch demonstrated potential as an oral probiotic carrier in terms of cost, suitability for functional foods, and commercialization potential.