Effect of Simulated Gastrointestinal Tract Conditions on Survivability of Probiotic Bacteria Present in Commercial Preparations

Potential probiotic Lactobacillus delbrueckii subsp. lactis KUMS-Y33 suppresses adipogenesis and promotes osteogenesis in human adipose-derived mesenchymal stem cell

Today, probiotics are considered to be living microorganisms whose consumption has a certain number of beneficial effects on the consumer. The present study aimed to investigate the effect of a new probiotic extract (Lactobacillus delbrueckii subsp. lactis KUMS Y33) on the differentiation process of human adipose-derived stem cells (hADSCs) into adipocytes and osteocytes and, as a result, clarify its role in the prevention and treatment of bone age disease. Several bacteria were isolated from traditional yogurt. They were evaluated to characterize the probiotic's activity. Then, the isolated hADSCs were treated with the probiotic extract, and then osteogenesis and adipogenesis were induced. To evaluate the differentiation process, oil red O and alizarin red staining, a triglyceride content assay, an alkaline phosphatase (ALP) activity assay, as well as real-time PCR and western blot analysis of osteocyte- and adipocyte-specific genes, were performed. Ultimately, the new strain was sequenced and registered on NBCI. In the probiotic-treated group, the triglyceride content and the gene expression and protein levels of C/EBP-α and PPAR-γ2 (adipocyte-specific markers) were significantly decreased compared to the control group (P < 0.05), indicating an inhibited adipogenesis process. Furthermore, the probiotic extract caused a significant increase in the ALP activity, the expression levels of RUNX2 and osteocalcin, and the protein levels of collagen I and FGF-23 (osteocyte-specific markers) in comparison to the control group (P < 0.05), indicating an enhanced osteogenesis process. According to the results of the present study, the probiotic extract inhibits adipogenesis and significantly increases osteogenesis, suggesting a positive role in the prevention and treatment of osteoporosis and opening a new aspect for future in-vivo study.

The Probiotic Properties and Safety of Limosilactobacillus mucosae NK41 and Bifidobacterium longum NK46

Probiotics should possess specific properties to exert beneficial effects, and their safety must be ensured for human consumption. The purpose of this study was to evaluate the probiotic properties and safety of Limosilactobacillus mucosae NK41 and Bifidobacterium longum NK46 isolated from human feces in vitro. Both strains exhibited high resistance to simulated gastrointestinal fluid. Furthermore, probiotic-related cell surface characteristics including auto-aggregation and cell surface hydrophobicity were assessed by measuring the absorbance at a wavelength of 600 nm, which demonstrated good auto-aggregation ability and affinity for xylene, indicating their effective adhesion to Caco-2 cells. In addition, hemolytic, gelatinase, and β-glucuronidase activities were found to be negative in both strains. The susceptibility to nine commonly used antibiotics was assessed using the broth macrodilution method, which demonstrated that both strains were susceptible to all tested antibiotics. Furthermore, L. mucosae NK41 and B. longum NK46 produced significantly higher levels of L-lactate (71.8 ± 0.7% and 97.8 ± 0.4%) than D-lactate (28.2 ± 0.7% and 2.2 ± 0.4%, respectively). Using PCR amplification to investigate genes associated with virulence factors, we found that neither strain harbored any virulence genes. These findings suggest that L. mucosae NK41 and B. longum NK46 have the potential to be used as probiotics and are considered safe for human consumption.

Assessment of probiotic properties of lactic acid bacteria isolated from an artisanal Colombian cheese

Lactic Acid Bacteria play an important role in the milk fermentation processes of traditional cheeses and have become an important target for the development of novel cheese cultures because of their ability to confer health benefits. This study aimed to evaluate the probiotic potential of 12 Lactic Acid Bacteria (LAB) strains previously isolated and molecularly identified from an artisanal Colombian Double-Cream Cheese. Probiotic properties, including safety (hemolysis and sensibility to antibiotics), pH and bile salt tolerance, auto-aggregation, cell surface hydrophobicity, antibacterial activity, and exopolysaccharide production, were examined. None of the strains were hemolytic, and Pediococcus (16, 18) and Lactobacillus (28, 29) were found to be sensitive to all antibiotics. Moreover, all the strains tolerated pH (3.0, 6.5 and 8.0) and bile salt conditions (0.3, 0.6 and 1.0 % w/v). Pediococcus pentosaceus (16), Leuconostoc citreum (17), Pediococcus acidilactici (18), Enterococcus faecium (21,22), Enterococcus faecalis (24) and Limosilactobacillus fermentum (29) exhibited medium autoaggregation and affinity to chloroform. Six of the strains exhibited a ropy exopolysaccharide phenotype. Antibacterial activity against foodborne pathogens, Salmonella Typhimurium ATCC 14028, Listeria monocytogenes ATCC 19111, Escherichia coli ATCC 25922 and Staphylococcus aureus ATCC 25923, was found to be strain dependent, with the strains 16, 18, 21, 26, 28 and 29 presenting a higher inhibition (>4 mm) against all of them. According to Principal Component Analysis, P. pentosaceus (16), Leu. mesenteroides (26), L. casei (28), L. fermentum (29), and E. faecium (21) showed strong probiotic properties. Our findings suggest that five strains out of the 12 sampled strains are potential probiotics that could be used in the processing of traditional dairy products on an industrial scale to improve their quality.

B. C, Huligere SS, Khan MS, Alafaleq NO, Ahmad S, Akhter F, Sreepathi N, P. A, Ramu R. Inhibition of carbohydrate hydrolyzing enzymes by a potential probiotic Levilactobacillus brevis RAMULAB49 isolated from fermented Ananas comosus

The research aimed to explore the potential probiotic characteristics of Levilactobacillus brevis RAMULAB49, a strain of lactic acid bacteria (LAB) isolated from fermented pineapple, specifically focusing on its antidiabetic effects. The importance of probiotics in maintaining a balanced gut microbiota and supporting human physiology and metabolism motivated this research. All collected isolates underwent microscopic and biochemical screenings, and those exhibiting Gram-positive characteristics, negative catalase activity, phenol tolerance, gastrointestinal conditions, and adhesion capabilities were selected. Antibiotic susceptibility was assessed, along with safety evaluations encompassing hemolytic and DNase enzyme activity tests. The isolate's antioxidant activity and its ability to inhibit carbohydrate hydrolyzing enzymes were examined. Additionally, organic acid profiling (LC-MS) and in silico studies were conducted on the tested extracts. Levilactobacillus brevis RAMULAB49 demonstrated desired characteristics such as Gram-positive, negative catalase activity, phenol tolerance, gastrointestinal conditions, hydrophobicity (65.71%), and autoaggregation (77.76%). Coaggregation activity against Micrococcus luteus, Pseudomonas aeruginosa, and Salmonella enterica serovar Typhimurium was observed. Molecular characterization revealed significant antioxidant activity in Levilactobacillus brevis RAMULAB49, with ABTS and DPPH inhibition rates of 74.85% and 60.51%, respectively, at a bacterial cell concentration of 109 CFU/mL. The cell-free supernatant exhibited substantial inhibition of α-amylase (56.19%) and α-glucosidase (55.69%) in vitro. In silico studies supported these findings, highlighting the inhibitory effects of specific organic acids such as citric acid, hydroxycitric acid, and malic acid, which displayed higher Pa values compared to other compounds. These outcomes underscore the promising antidiabetic potential of Levilactobacillus brevis RAMULAB49, isolated from fermented pineapple. Its probiotic properties, including antimicrobial activity, autoaggregation, and gastrointestinal conditions, contribute to its potential therapeutic application. The inhibitory effects on α-amylase and α-glucosidase activities further support its anti-diabetic properties. In silico analysis identified specific organic acids that may contribute to the observed antidiabetic effects. Levilactobacillus brevis RAMULAB49, as a probiotic isolate derived from fermented pineapple, holds promise as an agent for managing diabetes. Further investigations should focus on evaluating its efficacy and safety in vivo to consider its potential therapeutic application in diabetes management.

3D printing of microencapsulated Lactobacillus rhamnosus for oral delivery

3D Printing is an innovative technology within the pharma and food industries that allows the design and manufacturing of novel delivery systems. Orally safe delivery of probiotics to the gastrointestinal tract faces several challenges regarding bacterial viability, in addition to comply with commercial and regulatory standpoints. Lactobacillus rhamnosus CNCM I-4036 (Lr) was microencapsulated in generally recognised as safe (GRAS) proteins, and then assessed for robocasting 3D printing. Microparticles (MP-Lr) were developed and characterised, prior to being 3D printed with pharmaceutical excipients. MP-Lr showed a size of 12.3 ± 4.1 µm and a non-uniform wrinkled surface determined by Scanning Electron Microscopy (SEM). Bacterial quantification by plate counting accounted for 8.68 ±0.6 CFU/g of live bacteria encapsulated within. Formulations were able to keep the bacterial dose constant upon contact with gastric and intestinal pH. Printlets consisted in oval-shape formulations (15 mm × 8 mm × 3.2 mm) of ca. 370 mg of total weight, with a uniform surface. After the 3D printing process, bacterial viability remained even as MP-Lr protected bacteria alongside the process (log reduction of 0.52, p>0.05) in comparison with non-encapsulated probiotic (log reduction of 3.05). Moreover, microparticle size was not altered during the 3D printing process. We confirmed the success of this technology for developing an orally safe formulation, GRAS category, of microencapsulated Lr for gastrointestinal vehiculation.

Hydrogel Derived from Glucomannan-Chitosan to Improve the Survival of Lactobacillus acidophilus FNCC 0051 in Simulated Gastrointestinal Fluid

The probiotic encapsulating hydrogel derived from porang (Amorphophallus oncophyllus) glucomannan and chitosan was investigated with regard to its encapsulation efficiency, physical properties, prebiotic activity, and survival under simulated gastrointestinal conditions. The hydrogel's encapsulation efficiency was improved by varying the number of the Lactobacillus acidophilus FNCC 0051, which also served to increase the diameter (2-3 mm), polydispersity index (1.23-1.65), positive zeta potential, whiteness, and brightness of the hydrogel. Moreover, the hydrogel's prebiotic activity score was higher than that of inulin after 24 h of incubation, reflecting its role as a cell encapsulant, particularly when it comes to maintaining cells during exposure to simulated gastrointestinal fluid. The cell viability increased from 86% to 100% when immersed in intestinal juice, which is comparable to the increase achieved using alginate and konjac glucomannan hydrogels. Future animal studies are required to determine the cell viability in actual gastrointestinal conditions and assess the health effects of the hydrogel.

Immunostimulatory Activity of Lactic Acid Bacteria Cell-Free Supernatants through the Activation of NF-κB and MAPK Signaling Pathways in RAW 264.7 Cells

Lactic acid bacteria (LAB) can improve host health and has strong potential for use as a health functional food. Specific strains of LAB have been reported to exert immunostimulatory effects. The primary goal of this study was to evaluate the immunostimulatory activities of novel LAB strains isolated from humans and foods and to investigate the probiotic properties of these strains. Cell-free supernatants (CFS) obtained from selected LAB strains significantly increased phagocytosis and level of nitric oxide (NO) and pro-inflammatory cytokines such as tumor necrosis factor (TNF)-α and interleukin (IL)-6 in RAW264.7 macrophage cells. The protein expression of inducible NO synthase (iNOS) and cyclooxygenase (COX)-2, which are immunomodulators, was also upregulated by CFS treatment. CFS markedly induced the phosphorylation of nuclear factor-κB (NF-κB) and MAPKs (ERK, JNK, and p38). In addition, the safety of the LAB strains used in this study was demonstrated by hemolysis and antibiotic resistance tests. Their stability was confirmed under simulated gastrointestinal conditions. Taken together, these results indicate that the LAB strains selected in this study could be useful as probiotic candidates with immune-stimulating activity.

Exploring the Probiotic Potential of Dairy Industrial-Relevant Lactobacilli

Usually, the search for new candidate probiotics starts from strain isolation, followed by genotypic and phenotypic characterisations. For the best candidates, the final selection criteria, i.e., an efficient biomass production and the survival to stressful conservation processes, may often represent a bottleneck. The aim of this study is to reverse this classic bottom-up approach, thereby evaluating the in vitro probiotic properties of microbes that are already commercialized and employed in the dairy sector. The major advantage of reversing the traditional scheme is to deal with strains that are already suitable for the scale-up at the industrial level. In this work, four lactobacilli strains were analysed, belonging to the species of Lactiplantibacillus plantarum (strains PLA and PLA2) and Lacticaseibacillus rhamnosus (strains PAR4 and RHM). Both L. plantarum strains showed the best survival under simulated oro-gastrointestinal stress; PLA and PAR4 had the strongest inhibitory activity against all the tested harmful bacteria, with the latter strain showing also the highest percentage of Caco-2 adhesion; RHM was the best biofilm producer on abiotic surface. Finally, cell-free surnatants from all the strain cultures exhibited anti-inflammatory action on THP-1 macrophages. For all the studied strains, it is possible to claim beneficial functional properties other than the technological ones for which they are already marketed. The possible use of the four strains in a mixture could represent a strategy to diversify and maximize their beneficial potential. Nonetheless, future studies are necessary to validate in vivo the observed beneficial properties and to evaluate any effect of the vehicle product on the probiotic aptitude.

Compositional Quality and Possible Gastrointestinal Performance of Marketed Probiotic Supplements

The local pharmacies and shops are brimming with various probiotic products that herald a range of health benefits. The poor quality of probiotic products in both dosage and species is symptomatic of this multi-billion-dollar market making it difficult for consumers to single out reliable ones. This study aims to fill the potential gap in the labeling accuracy of probiotic products intended for human consumption. We describe a combinatorial approach using classical culture-dependent technique to quantify and molecular techniques (16 s rRNA gene sequencing, multilocus sequence, and ribotyping) for strain recognition of the microbial contents. The full gamut of probiotic characteristics including acid, bile and lysozyme tolerances, adhesiveness, anti-pathogenicity, and degree of safeness were performed. Their capacity to endure gastro-intestinal (GIT) stresses and select drugs was assessed in vitro. Our results forced us to declare that the local probiotic market is essentially unregulated. Almost none of the probiotic products tested met the label claim. Some (11%) have no viable cells, and a quarter (27%) showing significant inter-batch variation. A lower microbial count was typical with undesirables constituting a quarter of the total (~ 27%). Half of the products contained antibiotic-resistant strains; the unregulated use of these probiotics carries the risk of spreading antibiotic resistance to gut pathobionts. Poor tolerance to gut conditions and mediocre functionalism make the case worse. The current regulatory systems do not take this discrepancy into account. We recommend an evidence-based regular market surveillance of marketed probiotics to ensure the authenticity of the claims and product effectiveness.

Lactic Acid Bacteria Isolated from Fresh Vegetable Products: Potential Probiotic and Postbiotic Characteristics Including Immunomodulatory Effects

The ability to perform effectively in the gastrointestinal tract (GIT) is one of the most significant criteria in the selection of potential probiotic bacteria. Thus, the present study aimed to investigate the potential probiotic characteristics of some selected lactic acid bacteria (LAB) isolated from vegetable products. Probiotic characteristics included tolerance to acid and bile, cholesterol-removing ability, bile salt hydrolysis, resistance against lysozyme and antibiotics, production of exopolysaccharides (EPS), antimicrobial and hemolytic activities, and cell surface characteristics (auto-aggregation, co-aggregation, and hydrophobicity). The survival rate of isolates after G120 ranged from 8.0 to 8.6 Log₁₀ CFU/mL. After the intestinal phase (IN-120), the bacterial count ranged from 7.3 to 8.5 Log₁₀ CFU/mL. The bile tolerance rates ranged from 17.8 to 51.1%, 33.6 to 63.9%, and 55.9 to 72.5% for cholic acid, oxgall, and taurocholic acid, respectively. Isolates F1, F8, F23, and F37 were able to reduce cholesterol (>30%) from the broth. The auto-aggregation average rate increased significantly after 24 h for all isolates, while two isolates showed the highest hydrophobicity values. Moreover, isolates had attachment capabilities comparable to those of HT-29 cells, with an average of 8.03 Log₁₀ CFU/mL after 2 h. All isolates were resistant to lysozyme and vancomycin, and 8 out of the 17 selected isolates displayed an ability to produce exopolysaccharides (EPS). Based on 16S rRNA sequencing, LAB isolates were identified as Enterococcus faecium, E. durans, E. lactis, and Pediococcus acidilactici.

Physiological and Genomic Analysis of Bacillus pumilus UAMX Isolated from the Gastrointestinal Tract of Overweight Individuals

The study aimed to evaluate the metabolism and resistance to the gastrointestinal tract conditions of Bacillus pumilus UAMX (BP-UAMX) isolated from overweight individuals using genomic tools. Specifically, we assessed its ability to metabolize various carbon sources, its resistance to low pH exposure, and its growth in the presence of bile salts. The genomic and bioinformatic analyses included the prediction of gene and protein metabolic functions, a pan-genome and phylogenomic analysis. BP-UAMX survived at pH 3, while bile salts (0.2-0.3% w/v) increased its growth rate. Moreover, it showed the ability to metabolize simple and complex carbon sources (glucose, starch, carboxymethyl-cellulose, inulin, and tributyrin), showing a differentiated electrophoretic profile. Genome was assembled into a single contig, with a high percentage of genes and proteins associated with the metabolism of amino acids, carbohydrates, and lipids. Antibiotic resistance genes were detected, but only one beta-Lactam resistance protein related to the inhibition of peptidoglycan biosynthesis was identified. The pan-genome of BP-UAMX is still open with phylogenetic similarities with other Bacillus of human origin. Therefore, BP-UAMX seems to be adapted to the intestinal environment, with physiological and genomic analyses demonstrating the ability to metabolize complex carbon sources, the strain has an open pan-genome with continuous evolution and adaptation.