Animal and In Vitro Models as Powerful Tools to Decipher the Effects of Enteric Pathogens on the Human Gut Microbiota

Examining the interplay between intestinal pathogens and the gut microbiota is crucial to fully comprehend the pathogenic role of enteropathogens and their broader impact on human health. Valid alternatives to human studies have been introduced in laboratory practice to evaluate the effects of infectious agents on the gut microbiota, thereby exploring their translational implications in intestinal functionality and overall health. Different animal species are currently used as valuable models for intestinal infections. In addition, considering the recent advances in bioengineering, futuristic in vitro models resembling the intestinal environment are also available for this purpose. In this review, the impact of the main human enteropathogens (i.e., Clostridioides difficile, Campylobacter jejuni, diarrheagenic Escherichia coli, non-typhoidal Salmonella enterica, Shigella flexneri and Shigella sonnei, Vibrio cholerae, and Bacillus cereus) on intestinal microbial communities is summarized, with specific emphasis on results derived from investigations employing animal and in vitro models.

Antioxidant Effects and Probiotic Properties of Latilactobacillus sakei MS103 Isolated from Sweet Pickled Garlic

Fermented vegetable-based foods, renowned for their unique flavors and human health benefits, contain probiotic organisms with reported in vitro antioxidative effects. This study investigates the probiotic properties of Latilactobacillus sakei MS103 (L. sakei MS103) and its antioxidant activities using an in vitro oxidative stress model based on the hydrogen peroxide (H2O2)-induced oxidative damage of RAW 264.7 cells. L. sakei MS103 exhibited tolerance to extreme conditions (bile salts, low pH, lysozyme, H2O2), antibiotic sensitivity, and auto-aggregation ability. Moreover, L. sakei MS103 co-aggregated with pathogenic Porphyromonas gingivalis cells, inhibited P. gingivalis-induced biofilm formation, and exhibited robust hydrophobic and electrostatic properties that enabled it to strongly bind to gingival epithelial cells and HT-29 cells for enhanced antioxidant effects. Additionally, L. sakei MS103 exhibited other antioxidant properties, including ion-chelating capability and the ability to effectively scavenge superoxide anion free radicals, hydroxyl, 2,2'-azino-bis (3-ethylbenzothiazoline-6-sulfonic acid, and 2,2-diphenyl-1-picrylhydrazyl. Furthermore, the addition of live or heat-killed L. sakei MS103 cells to H2O2-exposed RAW 264.7 cells alleviated oxidative stress, as reflected by reduced malondialdehyde levels, increased glutathione levels, and the up-regulated expression of four antioxidant-related genes (gshR2, gshR4, Gpx, and npx). These findings highlight L. sakei MS103 as a potential probiotic capable of inhibiting activities of P. gingivalis pathogenic bacteria and mitigating oxidative stress.

Limosilactobacillus reuteri Regulating Intestinal Function: A Review

Probiotics have extensive use in daily life, due to the function of the changing intestinal metabolism and material conversion processes, wherein they remodel the intestinal microbiota, regulate the intestinal function and affect the organism’s health. Limosilactobacillus reuteri (L. reuteri), originally discovered in breast milk and currently reported to be present within the gut of almost all vertebrates and mammals, is an intestinal probiotic with prebiotic efficacy. Most L. reuteri have good intestinal colonization and bacteriocin secretion abilities, which can increase the expression of the mucin (mucoprotein) genes 2 MUC2 and MUC13, which in turn promote the development and maturation of intestinal organoids, and augment mucin secretion. In enteritis patients, L. reuteri downregulates α Tumor necrosis factor-α, (TNF-α), Interleukin-6 (IL-6), IL-8, and IL-12 expression to attenuate inflammation. It also induces the host’s production of immunoglobulin A (IGA), which manipulates the intestinal microbial community, inhibiting the growth of pathogens. L. reuteri has been widely used in daily life. with in-depth studies having been conducted on the prebiotic effects of L. reuteri. However, the complexity of its application in a clinical setting is still unclear because the pathogenesis of various diseases still requires a large amount of data and theoretical support.

Leuconostoc mesenteroides LVBH107 Antibacterial Activity against Porphyromonas gingivalis and Anti-Inflammatory Activity against P. gingivalis Lipopolysaccharide-Stimulated RAW 264.7 Cells

Probiotics, active microorganisms benefiting human health, currently serve as nutritional supplements and clinical treatments. Periodontitis, a chronic infectious oral disease caused by Porphyromonas gingivalis (P. gingivalis), activates the host immune response to release numerous proinflammatory cytokines. Here, we aimed to clarify Leuconostoc mesenterica (L. mesenteroides) LVBH107 probiotic effects based on the inhibition of P.gingivalis activities while also evaluating the effectiveness of an in vitro P.gingivalis lipopolysaccharide-stimulated RAW 264.7 cell-based inflammation mode. L. mesenteroides LVBH107 survived at acid, bile salts, lysozyme, and hydrogen peroxide conditions, auto-aggregated and co-aggregated with P. gingivalis, exhibited strong hydrophobicity and electrostatic action, and strongly adhered to gingival epithelial and HT-29 cells (thus exhibiting oral tissue adherence and colonization abilities). Moreover, L.mesenteroides LVBH107 exhibited sensitivity to antibiotics erythromycin, doxycycline, minocycline, ampicillin, and others (thus indicating it lacked antibiotic resistance plasmids), effectively inhibited P.gingivalis biofilm formation and inflammation (in vitro inflammation model), reduced the secretion of pro-inflammatory cytokines (TNF-α, IL-6 and IL-1β) and inflammatory mediators (NO and PGE₂), and decreased the expression levels of inflammation related genes. Thus, L.mesenterica LVBH107 holds promise as a probiotic that can inhibit P.gingivalis biofilm formation and exert anti-inflammatory activity to maintain oral health.

Streptococcus strain C17T as a potential probiotic candidate to modulate oral health

In the microbiome, probiotics modulate oral diseases. In this study, Streptococcus strain C17^T was isolated from the oropharynx of a five-year-old healthy child, and its potential probiotic properties were analysed using human bronchial epithelial cells (16-HBE) used as an in vitro oropharyngeal mucosal model. The results demonstrated that the C17^T strain showed tolerance to moderate pH ranges of 4-5 and 0.5-1% bile. However, it was more tolerant to 0.5% bile than 1% bile. It also demonstrated an ability to accommodate maladaptive oropharyngeal conditions (i.e., tolerating lysozyme at 200 μg mL-1) . It was also resistant to hydrogen peroxide at 0.8 mM . In addition, we found out that the strain possesses inhibitory activities against various common pathogenic bacteria. Furthermore, C17^T was not cytotoxic to 16-HBE cells at different multiplicities of infection. Scanning electron microscopy disclosed that C17^T adhesion to 16-HBE cells. Competition, exclusion, and displacement assays showed that it had good anti-adhesive effect against S. aureus. The present study revealed that Streptococcus strain C17^T is a potentially efficacious oropharyngeal probiotic.

Metagenomic insights into the bacteria responsible for producing biogenic amines in sufu

Harmful levels of biogenic amines (BAs) are frequently identified in sufu. The microorganisms and mechanisms responsible for BA production in sufu, however, are not well documented. In this study, sufu samples were randomly obtained from various regions of China. Putrescine, tyramine, and histamine were quantitated as the most abundant BAs. According to the metagenome sequencing, the abundances and diversities of genes encoding the critical enzymes in BA production were acquired. The results showed that genes encoding arginine-, ornithine-, tryptophan-, and histidine decarboxylases were the predominant amino acid decarboxylase genes. Furthermore, 34 metagenome-assembled genomes (MAGs) were generated, of which 23 encoded at least one gene involved in BA production. Genetic analysis of MAGs indicated genera affiliated with Enterococcus, Lactobacillus-related, and Lactococcus were the major histamine-synthesizing bacteria, and tyrosine may be utilized by Bacillus, Chryseobacterium, Kurthia, Lysinibacillus, Macrococcus, and Streptococcus to product tyramine. The critical species involved in two putrescine-producing pathways were also explored. In the ornithine decarboxylase pathway, Lactobacillus-related and Veillonella were predicted to be the main performers, whereas Sphingobacterium and unclassified Flavobacteriaceae were the dominant executors in the agmatine deiminase pathway. The present study not only explained the BAs formation mechanism in sufu but also identified specific bacteria used to control BAs in fermented soybean products.

Global transcriptomic analysis of Lactobacillus delbrueckii subsp. bulgaricus ATCC11842 reveals the role of LDB_RS05285 in the post-acidification of yogurt

During the storage of yogurt, acid-resistant bacteria continue to produce lactic acid (i.e., post-acidification process), leading to undesirable taste and flavor. Many methods have been proposed to inhibit post-acidification. However, the specific genes involved during this biological process have not yet been systematically studied. Hence, herein, we assessed the culture starter Lactobacillus delbrueckii subsp. bulgaricus ATCC11842 with regards to its transcriptomes under in vitro acid- and cold-culture conditions. Through differential gene expression analysis, we screened out 69 candidate genes that persistently responded to acid with or without cold stress. qPCR was then used to determine the in situ expression levels of these candidate genes at different stages of yogurt fermentation and storage. Genes whose expression levels did not change much from the end of fermentation to the early stage of yogurt storage were more likely to be post-acidification genes, as such stability indicated that they were not affected by cold stress. LDB_RS05285 was determined to be one such gene; the overexpression of this gene showed that the increase of gene expression could reduce the acid production of the strain without affecting normal growth. Therefore, the genetic manipulation techniques that increased the expression level of the LDB_RS05285 gene might have the potential to inhibit the post-acidification of yogurt. Thus, LDB_RS05285 plays an important role in the post-acidification process and would become a new target for regulating yogurt post-acidification.

Comparison of the composition and function of the gut microbiome in herdsmen from two pasture regions, Hongyuan and Xilingol

There is a close relationship between the gut microbiome and health in humans including regulation of immunity and energy metabolism. This study investigated differences in the gut microbiome of herdsmen from two regions: Hongyuan pasture in Sichuan and Xilingol pasture in Inner Mongolia. We found significant differences in the gut microbiome between the two groups. The main discriminatory species between the two groups were Bifidobacterium longum, Bifidobacterium breve, Phascolarctobacterium succinatutens, Prevotella stercorea, Prevotella copri, Eubacterium biforme, and Fusobacterium prausnitzii. The abundances of Bifidobacterium longum and Bifidobacterium breve were significantly lower in the gut microbiomes of Hongyuan herdsmen than in the gut microbiomes of Xilingol herdsmen. Functional metagenomic analysis showed that more genes were enriched in glycoside hydrolase and transposase in the gut microbiome of Hongyuan herdsmen compared with Xilingol herdsmen, suggesting a higher energy demand in the gut microbiome of Hongyuan herdsmen. Significantly more genes associated with glycolysis, starch degradation, and sucrose degradation were also found in the gut microbiome of Hong yuan herdsmen compared with Xilingol herdsmen. These results indicate that herdsmen from different pastoral regions had distinct gut microbiome composition and functions.

Barley-based probiotic food mixture: health effects and future prospects

Consumers around the globe are increasingly aware of the relation between nutrition and health. In this sense, food products that can improve gastrointestinal health such as probiotics, prebiotics and synbiotics are the most important segment within functional foods. Cereals are the potential substrates for probiotic products as they contain nutrients easily assimilated by probiotics and serve as the transporters of Lactobacilli through the severe conditions of gastrointestinal tract. Barley is one of the important substrates for the probiotic formulation because of its high phenolic compounds, β-glucans and tocols. The purpose of this review is to examine recent information regarding barley-based probiotic foods with a specific focus on the potential benefits of barley as a substrate for probiotic microorganisms in the development of dairy and nondairy based food products, and to study the effects of food matrices containing barley β-glucans on the growth and features of Lactobacillus strains after fermentation.

Antagonistic effects of Lactobacillus reuteri against Escherichia coli O157:H7 in white-brined cheese under different storage conditions

This study aimed to investigate the survival of the foodborne pathogen Escherichia coli O157:H7 in white-brined cheeses as influenced by the presence of Lactobacillus reuteri. The white cheeses were made from pasteurized bovine milk inoculated with E. coli O157:H7 (cocktail of 3 strains) to achieve ∼5 log₁₀ cfu/g with absence or presence of Lb. reuteri (∼6 log₁₀ cfu/g). Cheese samples were brined in 10% or 15% NaCl solution and stored at 10°C and 25°C for 28 d. The white-brined cheeses were assessed for salt content, pH, water activity (A_w), and numbers of E. coli O157:H7, Lb. reuteri, nonstarter lactic acid bacteria (NSLAB), yeasts, and molds. Results showed that E. coli O157:H7 survived in cheese stored in both brine solutions at 10°C and 25°C regardless of the presence of Lb. reuteri. A substantial reduction was observed in cheese stored in 10% NaCl brine at 25°C, followed by cheese stored in 15% NaCl brine at 10°C by 2.64 and 2.16 log₁₀ cfu/g, respectively, in the presence of Lb. reuteri and by 1.02 and 1.87 log₁₀ cfu/g, respectively, in the absence of Lb. reuteri under the same conditions. The pathogen in brine solutions survived but at a lower rate. Furthermore, the growth of Lb. reuteri and NSLAB were enhanced or slightly decreased in cheese and brine by 28 d, respectively. The salt concentrations of cheese ranged from 4 to 6% and 5 to 7% (wt/wt), during 28-d ripening in 10 and 15% brine, respectively. Values of pH and A_w slightly increased at d 1 after exposure to brine and reached 4.69 to 6.08 and 0.91 to 0.95, respectively, in all treatments. Therefore, the addition of Lb. reuteri can be used as a biopreservation method to inhibit the survival of E. coli O157:H7 in white-brined cheese when combined with the appropriate temperature, NaCl level, and storage time.

The Biotechnological Potential of Pediococcus spp. Isolated from Kombucha Microbial Consortium

In the past decade, the probiotic market has grown rapidly, both for foods and supplements intended to enhance wellness in healthy individuals. Different lactic acid bacteria (LAB), especially Lactobacillus spp., of different origins have already been used to develop commercial probiotic products. Nowadays, LAB new alternative sources, such as non-dairy fermented food products, are being exploited. One such source is Kombucha, a fermented low-alcohol beverage made of tea leaves. In this regard, we tested seven Pediococcus spp. strains isolated from a local industrial Kombucha for their biotechnological potential. Two, out of the seven isolates, identified as Pediococcus pentosaceus (L3) and Pediococcus acidiliactici (L5), were selected as successful candidates for the food industry, due to their probiotic and technological properties. In regard to their resistance in the gastro-intestinal tract, both selected strains were tolerant to a pH of 3.5, presence of 0.3% pepsin, and 0.5% bile salt concentration. On the antagonistic side, the fresh suspension of selected isolates had high inhibitory activity against pathogenic bacteria, such as Salmonella enterica Typhimurium, Listeria monocytogenes, Listeria ivanovii, Bacillus cereus, Proteus hauseri, and methicillin resistant Staphylococcus aureus. In addition, moderate to high inhibitory activity was noticed against foodborne molds (e.g., Penicillium expansum and Penicillium digitatum). These safety issues were supported by their negative hemolytic activity and good antioxidant potential (56-58%). Selected isolates were sensitive to ampicillin, penicillin, erythromycin, and lincomycin, while a broad range of other antibiotics were not effective inhibitors. On the technological side, both strains tolerated 5% NaCl and, during the freeze-drying process, had a good survival rate (86-92%). The selected Pediococcus strains have proven properties to be used for further development of functional products.

Stability assessment and improvement of a Lactobacillus plantarum mutant with low post-fermentation acidification characteristics

Intracellular pH homeostasis through the extrusion of a proton by F₀F₁-ATPase is one of the key mechanisms used by lactic acid bacteria in response to acid stress, and also influences their post-fermentation acidification. In this study, the genotypic and phenotypic stability of a low post-fermentation acidification (LPA) mutant (designated as DGCC12411^m) of Lactobacillus plantarum DGCC12411 was assessed. Compared with its mother strain, the pH of DGCC12411^m in De Man, Rogosa, and Sharpe (MRS) broth after 48-h cultivation was 0.35 pH units higher. Incorporation of DGCC12411^m in yogurt stored at ambient temperature (ambient yogurt) showed a reduced post-fermentation acidification during storage at 25°C for 120 d. Whole-genome sequencing analysis showed a SNP mutation (GGT > GAT at positions 505 to 507) in DGCC12411^m, which resulted in the substitution of a highly conserved glycine residue by aspartic acid at the Walker A motif of the F₀F₁-ATPase α-subunit. However, degeneration of the LPA phenotype was observed after 5 passages of DGCC12411^m in MRS broth. Analysis of DNA sequencing on both the whole population and the isolates showed that a back mutation occurred at the SNP site (GAT changed back to GGT) over the passaging, and the reversion gradually increased from a ratio of 10.8% at P5 to 60.0% at P10. We also found that the LPA phenotype stability of DGCC12411^m was improved by supplementing 0.1 M potassium phosphate buffer to the growth medium as well as by reducing the inoculation rate of DGCC12411^m to 2% (vol/vol). Such LPA Lactobacillus strains have potential for use as starter cultures in fermented foods with less change in acidity during shelf-life storage.

Isolation and Comparative Genomic Analysis of Reuterin-Producing Lactobacillus reuteri From the Chicken Gastrointestinal Tract

Lactobacillus reuteri is a natural inhabitant of selected animal and human gastrointestinal tract (GIT). Certain strains have the capacity to transform glycerol to 3-hydroxypropionaldehyde (3-HPA), further excreted to form reuterin, a potent antimicrobial system. Reuterin-producing strains may be applied as a natural antimicrobial in feed to prevent pathogen colonization of animals, such as in chicken, and replace added antimicrobials. To date, only seven L. reuteri strains isolated from chicken have been characterized which limits phylogenetic studies and host-microbes interactions characterization. This study aimed to isolate L. reuteri strains from chicken GIT and to characterize their reuterin production and antimicrobial resistance (AMR) profiles using phenotypic and genetic methods. Seventy strains were isolated from faces, crops and ceca of six chicken from poultry farms and samples from slaughterhouse. Twenty-five strains were selected for further characterization. Draft genomes were generated for the new 25 isolates and integrated into a phylogenetic tree of 40 strains from different hosts. Phylogenetic analysis based on gene content as well as on core genomes showed grouping of the selected 25 L. reuteri chicken isolates within the poultry/human lineage VI. Strains harboring pdu-cob-cbi-hem genes (23/25) produced between 156 mM ± 11 and 330 mM ± 14 3-HPA, from 600 mM of glycerol, in the conditions of the test. All 25 chicken strains were sensitive to cefotaxime (MIC between 0.016 and 1 μg/mL) and penicillin (MIC between 0.02 and 4 μg/mL). Akin to the reference strains DSM20016 and SD2112, the novel isolates were resistant to penicillin, possibly associated with identified point mutations in ponA, pbpX, pbpF and pbpB. All strains resistant to erythromycin (4/27) carried the ermB gene, and it was only present in chicken strains. All strains resistant to tetracycline (5/27) harbored tetW gene. This study confirms the evolutionary history of poultry/human lineage VI and identifies pdu-cob-cbi-hem as a frequent trait but not always present in this lineage. L. reuteri chicken strains producing high 3-HPA yield may have potential to prevent enteropathogen colonization of chicken.

High-Throughput Sequencing and Metabolomics Reveal Differences in Bacterial Diversity and Metabolites Between Red and White Sufu

Sufu is a traditional fermented soybean food produced in China. However, the microbial compositions and metabolites of different types of sufu have not been studied in detail. Accordingly, in this study, we evaluated the differences in bacterial communities and metabolites between commercial red sufu (RS) and white sufu (WS). Principal coordinate analysis and the unweighted pair group method with arithmetic means analysis of 16S rRNA genes revealed that the bacterial community structures of RS and WS differed dramatically. At the phylum level, the relative abundances of Firmicutes and Proteobacteria were significantly different between RS and WS (P < 0.01). Moreover, the abundances of Lactococcus and Tetragenococcus genera were significantly different between RS and WS (P < 0.01). Among metabolites, most free amino acids, few of volatile flavor compounds, and some organic acids showed significant differences between RS and WS (P < 0.05). Additionally, correlations between microbiota and metabolites were determined. Aggregated boosted tree analysis showed that formic acid had the highest relative influence (20.27%) on bacterial community diversity (Chao 1), following by arginine (5.38%), propanol (4.57%), oxalic acid (4.46%), and hexanol (4.43%). Moreover, Streptococcaceae and Moraxellaceae had the highest relative influence on the concentration of formic acid (12.84% and 8.75%, respectively). The profiles obtained in this study improve our understanding of the relationships between bacterial flora and metabolites in different types of sufu. These findings may help us interpret the roles of bacterial communities in the flavor and characteristics of sufu.

A Novel Shell Material-Highland Barley Starch for Microencapsulation of Cinnamon Essential Oil with Different Preparation Methods

Highland barley starch (HBS), as a carbohydrate shell material with excellent performance in microcapsule applications, has rarely been reported. In the present study, three different microcapsules (CEO-SWSM, CEO-PM, and CEO-UM) were synthesized successfully via saturated aqueous solution method, molecular inclusion method and ultrasonic method, respectively, using HBS as shell material coupled with cinnamon essential oil (CEO) as the core material. The potential of HBS as a new shell material and the influence of synthetic methods on the performance of microcapsules, encapsulation efficiency (EE), yield, and release rate of CEO-SWSM, CEO-PM, and CEO-UM were determined, respectively. The results confirmed that CEO-PM had the most excellent EE (88.2%), yield (79.1%), as well as lowest release rate (11.5%, after 25 days of storage). Moreover, different kinetic models were applied to fit the release process of these three kinds of microcapsules: CEO-SWSM, CEO-PM, and CEO-UM had the uppermost R-squared value in the Higuchi model, the zero-order model, and the first-level model, respectively. Over all, this work put forward a novel perspective for the improved encapsulation effect of perishable core materials (e.g., essential oil) for the food industry.

Dynamic comparison of gut microbiota of mice infected with Shigella flexneri via two different infective routes

Shigella is one of the main pathogens causing diarrheal disease, and is associated with high morbidity and mortality in developing countries. Previous clinical data and animal studies have shown that the outcomes of oral and peritoneal infections of Shigella differ, and that the latter is more serious. Furthermore, a variety of pathogenic bacteria are known to cause changes in intestinal flora after infection, and the influence of Shigella infection on intestinal flora remains poorly understood. In the present study, the 16S rRNA high-throughput sequencing method was used to compare the changes in gut microbiota profiles in feces of mice infected with Shigella via two routes. In addition, the present study investigated the association between the differences in infection performance and bacterial communities. The present results suggested that the intraperitoneal route induced a distinct decrease in α-diversity in the fecal microbiota when compared to the control at a later time, while the effect of the oral route on α-diversity was not obvious. Oral infection of Shigella had a rapid and significant effect on gut microbiota, mainly causing a decreased abundance of Lactobacillus and an increased abundance of Prevotella and Escherichia/Shigella in the early stage of infection. By contrast, the effect of intraperitoneal infection on the gut microbiota was relatively slow and small. The principal coordinate analysis results suggested that the dynamic profile of gut microbiota between the two infective routes was consistent with the infection process. Probiotics, such as Lactobacillus reuteri and Faecalitalea exhibited significantly reduced abundance after Shigella infection. Collectively, the present results suggested that gut microbiota may play a pivotal role in the pathogenesis of Shigella infection. Future studies should investigate the effect of Shigella infection on the interaction between pathogenic bacteria and intestinal flora. The present results suggested that the use of probiotics may facilitate the prevention and treatment of shigellosis.

Genomic analysis of Lactobacillus reuteri WHH1689 reveals its probiotic properties and stress resistance

Lactobacillus reuteri (L. reuteri) WHH1689, which was isolated from Chinese traditional highland barley wine, exhibited high survival period at room temperature in drinkable probiotic yogurt. This article aimed to indicate the genes involved in probiotic function of WHH1689 and reveal potential stress resistance based on genomic analysis. Analysis of comparative genome with closely related L. reuteri strains identified special stress adaptation. MUMmer and ACT softwares were applied for collinear analysis, and OrthoMCL program was used for sequence alignment involved in distribution of protein cluster. We identified genes coding for carbohydrate transport and enzymes, carbon metabolism pathway, gastrointestinal tract resistance, adhesive ability, and folic acid biosynthesis, etc. Genome sequence and comparative genome analysis of L. reuteri WHH1689 demonstrated specific genes for genetic adaptation and stress resistance. Tolerance, adhesion, and folate test indicated the strain had multiple probiotics. L. reuteri WHH1689 has the potential to be a probiotic candidate in dairy foods.

Isolation and Characterization of Potentially Probiotic Bacterial Strains from Mice: Proof of Concept for Personalized Probiotics

Modulation of the gut microbiota through the use of probiotics has been widely used to treat or prevent several intestinal diseases. However, inconsistent results have compromised the efficacy of this approach, especially in severe conditions such as inflammatory bowel disease (IBD). The purpose of our study was to develop a personalized probiotic strategy and assess its efficacy in a murine model of intestinal inflammation. Commensal bacterial strains were isolated from the feces of healthy mice and then administered back to the host as a personalized treatment in dextran sodium sulfate (DSS)-induced colitis. Colonic tissues were collected for histological analysis and to investigate inflammatory markers such as Il-1β, Il-6, TGF-β, and Il-10, and the enzyme myeloperoxidase as a neutrophil marker. The group that received the personalized probiotic showed reduced susceptibility to DSS-colitis as compared to a commercial probiotic. This protection was characterized by a lower disease activity index and reduced histopathological damage in the colon. Moreover, the personalized probiotic was more effective in modulating the host immune response, leading to decreased Il-1β and Il-6 and increased TGF-β and Il-10 expression. In conclusion, our study suggests that personalized probiotics may possess an advantage over commercial probiotics in treating dysbiotic-related conditions, possibly because they are derived directly from the host's own microbiota.

Complete Genome Sequence of Lactobacillus reuteri WHH1689, Isolated from Traditional Chinese Highland Barley Wine

Here, we report the complete genome sequence of Lactobacillus reuteri WHH1689, which was isolated from traditional Chinese highland barley wine in the Tibetan Plateau of China. The genome consists of a circular chromosome (2.04 Mb).