Postbiotics, the inactivated microorganisms and their products derived from fermentation, represent an evolution in the rapidly growing biotics industry and extend health benefits without the need for bacterial viability. In this study, we explored the potential of a novel oat-based postbiotic to provide health benefits by modulating the host immune system and gut microbiome. Two Lactobacillus species, Lactiplantibacillus plantarum 276 and Lacticaseibacillus rhamnosus GG, were used together to ferment 15% oat flour for 24 h at 37 °C followed by pasteurisation and freeze-drying to produce the oat-based postbiotic (OP). OP (1 mg/ml) was used to pretreat a mammalian intestinal epithelial cell line (Caco-2) for 1 h before stimulation with TNF-α and IL-1β (10 ng/ml each). The immuno-modulatory and barrier-supporting effect of OP were evaluated by measuring transepithelial electrical resistance (TEER), wound healing, and expression of cytokines genes (IL-6 and CXCL-8) as well as in a nematode (Caenorhabditis elegans) model. OP protected intestinal barrier integrity as measured by TEER in Caco-2 cells and in the C. elegans model. IL-6 and CXCL-8 expressions in OP pretreated cells were upregulated and OP promoted significant wound closure within 24 h. OP also markedly modulated the human gut microbiome as demonstrated by a 6.48-fold increase in native Bifidobacterium spp. in the in vitro human faecal model. Findings of this study suggest that OP is a novel, safe, stable, and effective intervention for foundational gut health and overall wellness.
The multi-strain probiotic formulation (MPF - Oxxyslab™) regulates several biological processes, including oxygenation in human and mouse models of neurodegenerative diseases. Its effect on oxidative metabolism of tumour cells has not yet been investigated. Employing a polarographic approach, we examined the effect of a lysate of MPF and its constituent strains on oxidative phosphorylation (OXPHOS) in colorectal cancer cells. Results indicate that MPF lysate selectively inhibits OXPHOS in undifferentiated but not in differentiated Caco-2 cells. Ceramides, produced through bacterial sphingomyelinase activity, mediate the inhibitory effects of MPF lysate, and the efficacy of the lysate of individual MPF strains in blocking cellular respiration varies due to strain-specific differences in ceramide production. Our results demonstrate that MPF lysate exhibits anti-OXPHOS activity in human colorectal carcinoma cells, selectively targeting undifferentiated Caco-2 cells but not differentiated ones. The reliance of colorectal cancer cells on OXPHOS provides a scientific basis for exploring MPF probiotic formulation as a complementary approach to conventional pharmacology.
Newborns with gastroschisis hospitalised in the neonatal intensive care unit (NICU) are at risk for a disrupted gut microbiome. Infants with gastroschisis are particularly vulnerable to a dysbiotic microbiome; they require prolonged parenteral nutrition (PN) due to intestinal dysmotility, which often leads to growth faltering (GF). This pilot study's goals were to (1) compare the gut microbiome in infants with gastroschisis to infants admitted to the NICU without congenital anomalies, (2) identify differences in the gut microbiome between infants with gastroschisis requiring prolonged PN and those who do not, and (3) compare the microbiome in infants with gastroschisis with GF to those without GF. This was a multi-site prospective cohort study including 17 infants born with gastroschisis and 16 infants with a gestational age greater than 34 weeks admitted to the NICU without congenital anomalies (controls). Prolonged PN was defined as more than 28 days. GF was defined as a decline in weight or length z-score from birth to discharge of ≤-0.8. Stool samples were collected weekly during hospitalisation and analysed by shotgun metagenomics to assess bacterial composition, diversity, and function. Gestational age and birth weight were similar in the gastroschisis group and the control group. Infants with gastroschisis showed increased Staphylococcus aureus and decreased Bifidobacterium longum. Those requiring prolonged PN had a reduced abundance of genes in the glucosidase pathway compared to those who did not. Infants with GF showed a lower abundance of genes involved in the NAD-diphosphatase pathway compared to those without GF. Infants with gastroschisis display a distinct microbial composition and function compared to NICU infants without this condition. Among infants with gastroschisis, differences in bacterial functional capacity were observed in those who required prolonged PN and developed GF.
Composition of the gut microbiota, and related short chain fatty acids (SCFAs) production can influence allergic status. Extensively hydrolysed casein (eHC) infant formulas are used for management of cow's milk protein (CMP) allergy; however, effects of eHC on gut microbiota as a potential mechanism contributing to benefits of eHC for infants with allergy are not well understood. This exploratory study aimed to assess the in vitro effects of eHC on infant gut microbial composition and metabolism. Two batches of a specific eHC preparation, along with a mixture of individual amino acids (AA), were first digested in the in vitro TNO Intestinal Model-1 (TIM-1) simulating infant upper gastrointestinal digestion conditions followed by an in vitro colon fermentation model inoculated with faeces from healthy, formula-fed infants. Peptide profile after digestion of the test compounds, as well as effects of the compounds on microbiota community structure and SCFA production were assessed. Overall peptide profiles of the eHC preparations (qualitative, based on liquid chromatography-mass spectrometry) remained largely unaffected by simulated upper gastrointestinal digestion. Faecal fermentation of the specific eHC preparations influenced microbiota composition, with a major impact on Bacteroides abundance. SCFA production was increased beyond control conditions by eHC but not AA. The impact of the AA mixture differed considerably from that of the eHC containing specific peptides. Results suggest that eHC formulas can impact microbiota composition and SCFA production in an in vitro colon fermentation model. While the descriptive results of this study require future confirmation under a more extensive experimental setup, it can be hypothesised that mechanisms modulating microbiota composition and metabolism occurring in infants fed with eHC formula for the management of CMP allergy might contribute to clinical observations related to allergy and tolerance development.
Fermented milk containing Lacticaseibacillus paracasei strain Shirota (LcS) has been shown to improve stool consistency in various countries; however, its effect on hard or lumpy stools (HLS) in the Vietnamese population remains unclear. We investigated the effects of LcS-fermented milk on constipated Vietnamese adults with a high prevalence of HLS. In a single-centre, open-label trial, 51 participants with HLS were randomised to receive one bottle per day of fermented milk containing ≥6.5 × 109 cfu of LcS for 4 weeks (probiotic group) or no intervention (control group), followed by a 2-week washout. The primary endpoint was the proportion of participants with HLS (Bristol Stool Form Scale score of 1 or 2) in ≥25% of bowel movements over 4 weeks. Secondary endpoints included total stool frequency, HLS frequency, ideal stool form, and defecation-related symptoms - all recorded in daily diaries. The Chinese Constipation Questionnaire (CCQ) and gut microbiota composition (16S rRNA sequencing) were assessed every 2 weeks. During the intervention, the probiotic group had a significantly lower proportion of participants with HLS in ≥25% of bowel movements compared to controls (odds ratio: 0.00; 95% confidence interval: 0.00-0.16; P = 0.005). The probiotic group also showed increased total stool frequency ( P = 0.001), reduced HLS frequency ( P = 0.035), and fewer participants with CCQ scores ≥5 indicating constipation ( P < 0.001) at 4 weeks. Gut microbiota beta-diversity differed between groups after 2 weeks ( P = 0.031), with reductions in Peptococcaceae, Clostridium_methylpentosum_group, and Clostridia (unclassified at the order level), followed by increases in Lachnospiraceae_UCG-004 at 4 weeks and Lachnospiraceae_ND3007_group post-follow-up ( P < 0.050), suggesting microbial changes linked to constipation improvement. No serious adverse events related to the intervention were observed. These findings support daily LcS-fermented milk as a dietary strategy in Vietnam to manage constipation via gut microbiota modulation. The study was registered at ClinicalTrials.gov (ID: NCT05982743).
Oxidative stress is a significant contributor to neuronal damage in multiple sclerosis (MS), marked by an imbalance in reactive oxygen species and antioxidant defences. Probiotics may modulate oxidative stress and improve antioxidant levels. This double-blind, randomised, placebo-controlled clinical trial aimed to evaluate the effects of probiotics supplementation on serum oxidative stress markers and endogenous antioxidants in patients with relapsing-remitting MS (RRMS). Ninety RRMS patients with expanded disability status scale [EDSS] < 4 were randomised into two groups: a probiotics group (Lactocare®) and a placebo group, and received the interventions twice daily for four months. Serum levels of oxidative stress markers (malondialdehyde [MDA]), endogenous antioxidants (glutathione peroxidase [GPx] activity, superoxide dismutase [SOD], catalase activity [CAT], glutathione [GSH]), and total antioxidant capacity (TAC) were measured at baseline and post-treatment. Fifty-five patients, including 26 patients in the probiotic group and 29 patients in the placebo group, completed the study. Both groups showed significant within-group improvements in GPx activity, SOD, and GSH levels, as well as reductions in MDA levels ( P < 0.05); however, no significant between-group differences were found for any markers ( P > 0.05). TAC and CAT levels remained unchanged in both groups. Findings of this study did not support the evidence for antioxidant effects of probiotics supplementation in RRMS patients, and its effects on oxidative stress markers in RRMS patients are found to be comparable to placebo. Iranian Registry of Clinical Trials: IRCT20220713055465N2, registration date: 2023.5.9.
Obesity is a growing public health concern in the Middle East and North Africa (MENA) region, yet limited research has explored how gut microbiota varies between Arab populations. This study compared the gut microbiota composition and diversity of Emirati and Lebanese adults with obesity and assessed the role of age and nationality in shaping microbial variation. A total of 43 Emirati and 30 Lebanese individuals with obesity (body mass index (BMI) ≥35 kg/m2) were recruited. Participants provided anthropometric and biochemical data, dietary records, and stool samples for 16S rRNA sequencing. The analysis revealed significantly higher BMI, weight, and fat mass in Emirati participants, while Lebanese individuals reported higher fibre intake. Taxonomic profiling showed higher relative abundances of Pseudomonadota, Mycoplasmatota, Cyanobacteriota, and Lentisphaerota in the Lebanese group, whereas Bacteroidota was more abundant among Emiratis. Lebanese participants also exhibited significantly greater microbial alpha-diversity. Beta-diversity analysis confirmed clear distinctions in microbial community structure between the two groups. Linear Discriminant Analysis Effect Size (LefSe) (LDA score >10log2) and regression models ( P < 0.05) identified specific bacterial genera associated with nationality, although these associations were attenuated after adjusting for age. These findings suggest that gut microbiota in Arab populations is influenced by demographic, dietary, and environmental factors, emphasising the need for culturally tailored microbiota-based strategies to manage obesity and related metabolic conditions.
Irritable bowel syndrome (IBS) is a chronic functional disorder characterised by abdominal pain and altered bowel habits. The most prevalent subtype is diarrhoea-predominant IBS (IBS-D). The combination of Bacillus subtilis HU58 and Heyndrickxia faecalis (formerly Bacillus coagulans) SC208 has previously exerted positive effects in people with antibiotic-associated diarrhoea and infective diarrhoea. The present multicentre study conducted in India aimed to evaluate the effectiveness and safety of the dual-strain probiotic in adults (18-65 years) with IBS-D. In this randomised, double-blind, placebo-controlled pilot study, 61 participants were recruited and assessed for changes in abdominal pain intensity (Numeric Rating Scale, NRS) and stool consistency (Bristol Stool Form Scale, BSFS) over a 4-week intervention period, with secondary outcomes including responder rates for IBS Global Assessment of Improvement (IBS-GAI) and perceived stress (Perceived Stress Scale, PSS). The probiotic group showed significantly higher overall responder rates for both abdominal pain and stool consistency ( P = 0.003) compared to the placebo group. Significant improvements were observed in abdominal pain ( P = 0.003) and stool consistency ( P = 0.035) scores in the probiotic versus placebo group from baseline to end of intervention. IBS-GAI responder rates were significantly higher among the probiotic versus placebo group ( P = 0.017) whilst perceived stress scores did not differ significantly between groups. In conclusion, supplementation with B. subtilis HU58 and H. faecalis SC208 for 4 weeks was safe and effective in improving stool consistency and abdominal pain in individuals with IBS-D, supporting its potential for symptom management in IBS-D. The trial is registered at https://ctri.nic.in/Clinicaltrials (CTRI/2022/07/044154).
The viability and persistence of orally administered microbes in the human gut are essential to their biological function. We previously described the development of two synbiotic medical foods, SBD111 and SBD121, each comprising four food-derived microbial strains and prebiotic fibres for the dietary management of postmenopausal bone loss and rheumatoid arthritis, respectively. Here, we report a randomised, open-label clinical study examining gut persistence of SBD111 and SBD121 microbes by testing faecal samples from healthy adults following administration for seven days. Thirty-eight participants, aged 18-64 years with a body mass index (BMI) of 18.5-35 kg/m2, were randomised to receive one of the two synbiotic medical foods daily for one week, followed by a four-week monitoring period. Employing quantitative PCR (qPCR), shotgun metagenomics, and culture-based assays, we evaluated the presence and viability of the microbial strains comprising each synbiotic medical food during and after administration. SBD111 and SBD121 were well-tolerated with minimal adverse events reported. Strains were detected in over 80% of participants during the administration period, with strain abundance peaking in the first week. Persistence in the follow-up period varied by strain and detection method. The microbial strains were detected by qPCR and metagenomic sequencing for a median of seven days and three days during the follow-up period, respectively. However, Bacillus amyloliquefaciens was consistently detected for seven days by both methods. Culture-based assays confirmed the presence of viable strains from both synbiotic medical foods in stool samples up to one-week post-consumption. Faecal metagenome diversity and metabolic functional potential remained stable throughout the administration and follow-up periods. Collectively, these results establish that SBD111 and SBD121 deliver viable microbes that transiently persist in the gut, reinforcing their promise for safe and targeted dietary interventions and highlighting the value of multi-platform detection strategies for comprehensive microbial persistence assessment. This trial, funded by Sōlarea biō, is registered at ClinicalTrials.gov (NCT06614166).
Health care practitioners (HCPs) strive to provide the best medical care for each individual patient. The question as to what constitutes 'the best' does, however, not have a single straightforward answer. Evidence-based Medicine (EBM) and Personalized Medicine (PM) are two paradigms that have emerged as means to improve intervention selection. Both paradigms have their own strengths and weaknesses that affect their use in clinical decision-making. In this review we discuss the strengths and weaknesses from the patient's and HCP perspective: how to find the best intervention for a particular patient. We review methodological and practical aspects, and zoom out from the scientific level to the epistemological level to integrate EBM and PM. Both EBM and PM are based on a realist worldview and by adopting a pragmatist worldview the strengths of both paradigms can be combined. We apply this pragmatic approach, called Evidence-based Personalized Medicine (EBPM), to microbiome-targeting interventions. The example EBPM implementation uses four steps. First, it allows HCPs to provide information (clinical diagnosis, complaints, patient needs, laboratory measures) about an individual patient. Second, it uses a GRADE-based system to grade evidence of specific intervention components. Next, it combines the patient profile data and preferences with the graded evidence, to come to a suggestion for a personalized intervention. Finally, this method enables gathering of treatment effects providing feedback into the system and further improve suggestions for future patients.
Oxidative stress plays a key role in colitis, a type of Inflammatory Bowel Disease, particularly when associated with a high-fat diet (HFD). Probiotics are known to alleviate inflammation through multiple mechanisms. This study aimed to evaluate the efficacy of a potential probiotic mixture with high antioxidant activity in attenuating colitis in mice fed either a normal diet (ND) or an HFD, with a focus on oxidative stress-related pathways. Eighty-eight Lactobacillus and Bifidobacterium strains isolated from healthy human faeces and milk were screened for antioxidant capacity. The six most active strains were selected to formulate a probiotic cocktail. Male C57BL/6 mice were divided into ND and HFD groups, each receiving dextran sulphate sodium (DSS) alone or combined with the probiotic cocktail. Disease indices, histopathology, and the expression of genes related to NF-kB and Nrf2 signalling, as well as oxidative and inflammatory markers, were assessed. Mice treated with the probiotic cocktail showed significant attenuation of DSS-induced colitis, evidenced by lower Disease Activity Index and pathological scores, and improved intestinal morphology ( P < 0.05). Both dietary groups exhibited elevated antioxidant enzyme activity and anti-inflammatory cytokine levels ( P < 0.05). The modulation of Nrf2 and NF-kB-related gene expression was more pronounced in ND-fed mice. The findings suggest that this novel probiotic cocktail can effectively alleviate colitis symptoms, likely by regulating oxidative stress and inflammatory pathways. Its incorporation as an adjunct therapy, particularly alongside a balanced diet, may offer a promising strategy for colitis management.
We investigated the therapeutic potential of Lactobacillus salivarius in colitis mice, and the mice were randomly allocated into three groups with each consisting of 10 mice (n = 10): a control group (CSG), a DSS-induced colitis model group (DSG), and a L. salivarius intervention group (LSG). The intervention group received daily oral administration of L. salivarius for seven consecutive days. Compared to the DSS model group, mice receiving L. salivarius exhibited significantly reduced weight loss, lower DAI scores, lessened colon shortening, and improved histopathological profiles, indicating a substantial reduction in inflammatory damage. Additionally, ITS sequencing revealed that L. salivarius significantly influenced the composition of the intestinal fungal community, decreasing the abundance of pathogenic fungi, such as Candida species, by approximately 40%, and restoring fungal homeostasis by reducing the Basidiomycota/Ascomycota ratio. Moreover, L. salivarius effectively alleviated DSS-induced oxidative stress by lowering serum MDA levels while enhancing the activity of SOD and GSH-Px. Furthermore, the probiotic intervention resulted in 30-40% reduction in pro-inflammatory factors (TNF-α, IL-6, and IL-1β) and an increase in the anti-inflammatory factor IL-10 levels, suggesting a pronounced anti-inflammatory effect. In conclusion, L. salivarius exerts significant protective effects against DSS-induced colitis by modulating the gut fungal community, mitigating oxidative stress, and suppressing inflammatory responses. This study is novel in that few probiotic studies have investigated the impact of L. salivarius on gut fungi in DSS-induced colitis. These findings highlight its potential as a therapeutic candidate for managing inflammatory bowel disease.
Although several internationally recognised scientific groups and non-governmental organisations have attempted to define 'postbiotics,' there remains no consensus. Leading experts have highlighted persistent problems of terminological inconsistency, lack of standardisation, and unclear boundaries between related concepts. What is needed is a comprehensive analysis that integrates existing definitions with considerations of manufacturing processes, mechanisms of action, and clinical applications. Ultimately, progress requires harmonisation of terminology to ensure comparability across studies and to provide a solid foundation for both academic and industry development.
Abnormal colonisation of the ileal mucosa by adherent-invasive Escherichia coli (AIEC) is a key feature of Crohn's disease. To date, no curative treatment for this disease exists, highlighting the need to develop new therapies targeting the origin of the inflammation, in particular the intestinal microbiota and more specifically AIEC. This study investigated the anti-virulence properties of 17 bacterial strains (lactobacilli and bifidobacteria) and three plant extracts (walnut and green tea leaves and liquorice roots) against AIEC. In vitro, six lactobacilli strains and one bifidobacterium strain reduced AIEC LF82 adhesion to Caco-2/TC7 cells and/or suppressed IL-8 secretion induced by AIEC. Although plant extracts did not prevent adhesion or inflammation, they inhibited AIEC growth. In a murine model of dextran sulfate sodium-induced colitis exacerbated by LF82 infection, two Lacticaseibacillus strains, one Bifidobacterium strain, and walnut and green tea extracts efficiently alleviated colitis and reduced faecal lipocalin-2 levels. For the green tea extract and one Lacticaseibacillus strain, beneficial effects were correlated with a decreased number of AIEC associated with the colonic mucosa. Building on these findings, bacteria and plant extract combinations were tested in the same model. A formulation combining two Lacticaseibacillus strains (Lbs. casei and Lbs. rhamnosus) with the walnut extract demonstrated the greatest efficacy, markedly reducing colitis score and preserving intestinal mucosa integrity. While untreated mice remained heavily colonised, the combination promoted AIEC elimination from the gut of half the mice, contributing to the alleviation of colitis symptoms. These results highlight the ability of combinations of specific bacteria/plant extracts to limit the presence of AIEC in the ileal mucosa of Crohn's disease patients, presenting a promising approach for disease management.
Irritable bowel syndrome (IBS) is faced by gastroenterologists daily, and probiotics are a potential therapeutic tool; however, there are no strain recommendations. This multicenter, real-world, single-arm, open-label study aims to assess a novel probiotic mixture's effectiveness, safety, and patient satisfaction in patients with IBS. This study was conducted by 52 Italian gastroenterologists across 16 of the 21 Italian regions who enrolled patients with IBS (n = 1,098). Throughout the 8-week treatment (T1) period with a probiotic mixture (Lactobacillus paracasei 101/37 LMG P-17504, Lactobacillus plantarum 14D CECT 4528, Bifidobacterium breve Bbr8 LMG P-17501, Bifidobacterium breve BL10 LMG P-17500, and Bifidobacterium animalis ssp. lactis Bi1 LMG P-17502), participants completed a questionnaire to evaluate IBS symptoms at baseline, at the end of treatment, and after one-month follow-up (T2). The primary outcome was the progress of abdominal pain and bloating according with a 5-point Likert scale, (0 absence and 5 highly intense symptoms) and treatment success was defined as a change towards categories of lower IBS severity for abdominal pain and/or bloating. Treatment success for abdominal pain and bloating was achieved in 73% and 81.9% at T1 and 68% and 73.1% at T2, respectively. The probiotic was associated with significantly reducing abdominal pain and bloating at T1 and T2 (P < 0.001). Patients with regular bowel movements increased to 68.5% at T1 and 68.7% at T2, respectively (P < 0.001). Patients reporting that IBS did not affect their daily life increased from 1.8% at entry to 22.7% at T1 and 41.6% at T2 (P < 0.001). This real-world, single-arm, open-label study showed that an 8-week treatment with a novel probiotic mixture is effective, safe, well tolerated, and can improve patients' social lives during and after treatment. Future randomised placebo-controlled studies are necessary to validate these findings. The trial is registered at www.ClinicalTrials.gov (NCT06610149).
The effects of probiotics on the gut microbiota and microbial metabolites in healthy individuals are not well understood. Faecal and serum samples were collected at the start and end of a 3-month, double-blind, placebo-controlled, randomised study with three different probiotic formulations in free-living, healthy adults. The composition of the faecal microbiota and levels of faecal and/or serum short-chain fatty acids (SCFA) and bile acids (BA) were measured and the probiotic formulations were found to impart differing effects including shifts in the composition and structure of the faecal microbiota, enhanced levels of circulating short chain fatty acids such as butyrate and propionate, and elevated levels of sulphated bile acids in faeces. This was in contrast to the outcomes for the placebo population where very little change occurred over the study. These findings demonstrate that probiotic supplementation elicits formulation specific effects and that there are potential benefits for healthy individuals.
Equol is an isoflavone produced by intestinal microbiota from daidzein. It has been assumed that individuals with equol-producing microbiota are those who mainly benefit from isoflavone consumption. However, no obvious genotypic differences can be found between the microbiota of equol-producing individuals and non-equol-producing individuals. The aim of this work was to find phenotypic differences in isoflavone metabolism between equol-producing and non-equol-producing intestinal microbiota. Of the 17 faecal samples used in this work, six produced equol from both daidzein and dihydrodaidzein (DHD); however, only equol-producing faecal samples produced 5-hydroxy-equol from genistein and dihydrogenistein (DHG). The equol producing microbiota metabolised most of daidzein, genistein, DHD and DHG present in the medium, while the metabolism of daidzein and genistein by non-equol producing microbiota is much lower, and they do not metabolise DHD and DHG. Moreover, equol-producing faecal samples produced lower concentrations of O-DMA than the non-equol-producing faecal samples. In addition, we demonstrated that most of the O-DMA is produced from daidzein. Therefore, there are important phenotypic differences between equol-producing and non-equol-producing intestinal microbiota, and these differences explain the differentiation between equol-producing and non-equol-producing individuals, and help to understand the metabolism of isoflavones by microbiota and how intestinal microbiota is responsible for the benefits of isoflavone intake.
Lactobacillus johnsonii CRL1647 has been studied due to its beneficial effects on Apis mellifera L. bee colonies. In this work, we analyzed the characteristics of its cell envelope and the relationship of this bacterial structure with adhesion. The study revealed that CRL1647 cells did not harbor S-layer proteins, whereas L. acidophilus ATCC4356, used as a positive control, showed a typical S-layer protein band. L. johnsonii CRL1647 hemagglutinated with sheep erythrocytes. Interestingly, the hemagglutination abilities of L. johnsonii CRL1647 were affected by the treatments with proteinase K and sodium metaperiodate. Transmission electron microscopy (TEM) analysis confirmed that L. acidophilus ATCC4356 has S-layer and revealed that the L. johnsonii CRL1647 cell surface was full of prolongations like 'hairs'. These ultra-structures completely disappeared after the treatment with proteinase K. The CRL1647 strain was able to efficiently adhere to intestinal epithelial cells and was phagocyted by macrophages. Both, adhesion and phagocytosis were significantly diminished when CRL1647 cells were pretreated with proteinase K. From these results, it can be inferred that the principal molecules involved in the adherence of L. johnsonii CRL1647 have a glycoprotein structure, differing them from S-layer proteins.
Probiotics offer numerous health benefits and are increasingly incorporated into dietary supplements and food products. Rigorous safety evaluations are essential to ensure their suitability for human consumption. This study evaluates the safety profile of Lactiplantibacillus plantarum N13, isolated from traditional fermented dairy products, through genomic and phenotypic analyses. Whole-genome sequencing confirmed general length of strain N13 (containing three plasmids) is about 3,318,516 bp, GC content is 44.4% and the absence of antibiotic resistance and virulence genes. Antibiotic susceptibility tests demonstrated that N13 is sensitive to ampicillin (1 μg/ml), gentamycin (4 μg/ml), kanamycin (32 μg/ml), erythromycin (0.5 μg/ml), clindamycin (0.25 μg/ml), tetracycline (32 μg/ml), and chloramphenicol (8 μg/ml), meeting the European Food Safety Authority (EFSA) guidelines. Additionally, genome analysis confirmed that N13 lacks genes related to biogenic amine biosynthesis, indicating its low risk of biogenic amine production. Scanning electron microscopy confirmed that N13 cells exhibited typical L. plantarum morphology. Phenotypic assays demonstrated that N13 is non-hemolytic and lacks harmful enzyme activity, including α-galactosidase, β-glucuronidase, and α-mannosidase. Acute and 28-day oral toxicity tests demonstrated that N13 was well tolerated in both Immunocompetent Research mice and Sprague Dawley rats, with no observable toxic effects or adverse changes even at high doses. At the recommended dose (0.5 × 1010 CFU/kg), N13 exhibited good oral safety. These findings establish L. plantarum N13 as a safe and promising probiotic strain, paving the way for its further application in dietary and functional food products.
This study investigated the effects of Dysosmobacter welbionis J115T on stress- and anxiety-related behaviours, inflammation, and neurobiological markers under different dietary conditions in female mice. Daily oral gavage with D. welbionis J115T for six weeks did not significantly impact body weight or fat mass, regardless of dietary treatment. Notably, high-fat diet (HFD)-fed female mice displayed increased body weight and adipose tissue accumulation compared to control diet (CTD) counterparts; however, this was not significantly altered by D. welbionis J115T administration. Behavioural testing revealed that HFD-fed female mice exhibited a mild stress/anxiety-like phenotype, especially in the elevated plus maze (EPM) and forced swim test (FST), which was attenuated by D. welbionis J115T treatment. These mice showed increased exploratory behaviour in the light-dark test (LDT), reduced time spent in closed arms of the EPM, and longer cumulative time in a highly active state in the FST. Plasma corticosterone levels, elevated post-behavioural testing in all female groups, increased less in HFD-fed D. welbionis-treated mice, suggesting a blunted stress response. These findings highlight sex-specific behavioural and molecular responses to dietary and probiotic interventions and suggest that D. welbionis J115T may modulate stress-related behaviours in female mice via the gut-brain axis.
