In health, the gut microbiome functions as a stable ecosystem maintaining overall balance and ensuring its own survival against environmental stressors through complex microbial interaction. This balance and protection from stressors is maintained through interactions both within the bacterial ecosystem as well as with its host. As a consequence, the gut microbiome plays a critical role in various physiological processes including maintaining the structure and function of the gut barrier, educating the gut immune system, and modulating the gut motor, digestive/absorptive, as well as neuroendocrine system all of which are crucial for human health and disease pathogenesis. Pre- and probiotics, widely available and clinically established, offer various health benefits primarily by beneficially modulating the gut microbiome. However, their clinical outcomes can vary significantly due to differences in host physiology, diets, individual microbiome compositions, and other environmental factors. This perspective paper highlights emerging scientific insights into the importance of microbial micronutrient sharing, gut redox balance, keystone species, and the gut barrier in maintaining a diverse and functional microbial ecosystem, and their relevance to human health. We propose a novel approach that targets microbial ecosystems and keystone taxa performance by supplying microbial micronutrients in the form of colon-delivered vitamins, and precision prebiotics [e.g. human milk oligosaccharides (HMOs) or synthetic glycans] as components of precisely tailored ingredient combinations to optimize human health. Such a strategy may effectively support and stabilize microbial ecosystems, providing a more robust and consistent approach across various individuals and environmental conditions, thus, overcoming the limitations of current single biotic solutions.

Drug abuse poses an enormous threat to global public health. Long-term drug abuse can reduce the quality of life of patients and increase the healthcare burden on society. There is growing interest in developing new methods to mitigate the effects of drug abuse. The gut microbiota plays a key role in maintaining homeostasis within the brain-gut-lung axis, which is critical in drug-abusing patients. The microbiota-brain-gut-lung axis refers to the interactions of microbes with the brain, gut, and lung. The effects of drug abuse on the gut microbiota are increasingly recognized, especially the pathogenesis by which the microbiota-brain-gut-lung axis is involved in regulating organ-organ communication, to explore new therapeutic approaches for clinical drug abuse. Currently, in addition to antibiotics, antiviral drugs, anti-tumor drugs, corticosteroids, drugs for the treatment of neurodegenerative diseases, and anesthetics also cause gut microbiota imbalance. This review summarizes the effects of drug abuse on gut microbiota and the important role of the microbiota-brain-gut-lung axis in drug abuse. Identifying changes in the gut microbiota associated with drug abuse and their underlying mechanisms under the principles of predictive, preventive, and personalized medicine (PPPM) is a critical step toward achieving PPPM. These strategies include FMT, probiotic supplements, and engineered bacteria that can benefit sub-healthy individuals with gut dysbiosis caused by drug abuse.

Restriction of dietary carbohydrates, fat and/or protein is often used to reduce body weight and/or treat (metabolic) diseases. Since diet is a key modulator of the human gut microbiome, which plays an important role in health and disease, this review aims to provide an overview of current knowledge of the effects of macronutrient-restricted diets on gut microbial composition and metabolites. A structured search strategy was performed in several databases. After screening for inclusion and exclusion criteria, thirty-six articles could be included. Data are included in the results only when supported by at least three independent studies to enhance the reliability of our conclusions. Low-carbohydrate (<30 energy%) diets tended to induce a decrease in the relative abundance of several health-promoting bacteria, including Bifidobacterium, as well as a reduction in short-chain fatty acid (SCFA) levels in faeces. In contrast, low-fat diets (<30 energy%) increased alpha diversity, faecal SCFA levels and abundance of some beneficial bacteria, including Faecalibacterium prausnitzii. There were insufficient data to draw conclusions concerning the effects of low-protein (<10 energy%) diets on gut microbiota. Although the data of included studies unveil possible benefits of low-fat and potential drawbacks of low-carbohydrate diets for human gut microbiota, the diversity in study designs made it difficult to draw firm conclusions. Using a more uniform methodology in design, sample processing and sharing raw sequence data could foster our understanding of the effects of macronutrient restriction on gut microbiota composition and metabolic dynamics relevant to health. This systematic review was registered at https://www.crd.york.ac.uk/prospero as CRD42020156929.

Limosilactobacillus reuteri DSM 17938 is among the world's most studied probiotic strains and has been shown to provide several health benefits for the host. We have previously shown that the cell-free supernatant of L. reuteri DSM 17938 possesses antimicrobial activity and contains several bioactive compounds. Furthermore, the strain was shown to be a biofilm producer that releases both planktonic and biofilm Membrane Vesicles (MVs). In this study, membrane vesicles isolated from planktonic (pMVs) and biofilm (bMVs) phenotypes were comparatively investigated for their toxicity, ability to kill cancer as well as non-cancer cell lines and modulate phagocytosis in murine macrophages. Neither pMVs nor bMVs showed any in vivo toxicity in a Galleria mellonella model, and weakly affected cancer and noncancerous cell viability after both short- and long-term treatments. However, they were able to affect phagocytosis in lipopolysaccharide challenged RAW 264.7 macrophages, suggesting possible immunomodulatory properties. NMR-based metabolomic analysis of pMVs and bMVs identified and quantified engulfed compounds, mainly organic acids and amino acids, with lactate being the most abundant molecule in both vesicle types. bMVs contained higher concentrations of all measured metabolites compared to pMVs. Proteomic analysis of pMVs and bMVs described equivalent protein cargos, emphasizing quantitative compositional differences that presumably reflect the physiological state of each parent bacterial phenotype. Through the assignment of molecules possibly acting as mediators of immune/inflammatory responses in the host and/or modulating known beneficial effects of L. reuteri, important signaling functions of these vesicles were suggested. Finally, storage stability of MVs up to four weeks was established.

Genital opening or vaginal canal (VC) in women has different embryological origin than the entire female reproductive system. The microenvironment of the VC post puberty is everchanging due to the hormonal fluctuations in a woman's body. However, the vaginal canal maintains a defined microbiota with higher population of inherent lactic acid bacteria (LAB) species under healthy conditions. The preservation of the beneficial flora in the genital area is dependent on genetic, social, and habitual factors. The understanding and practice of these factors prevents the commencement of various vaginal infections/vaginitis. Common vaginal infections have known antibiotic treatments; however, treatments of few infections are still unavailable. The study of sexual health is scarce in India due to social and economic factors, with less number of studies from various parts of the country. Thus, there is a necessity of new-age prophylactic solutions in such developing countries. This review highlights the origin of the female reproductive system and describes how the hormonal change initiates unique microenvironment development. Later, we have elaborately discussed the precautionary contribution of lactic acid bacteria and their unexplored commercial utilization, which in turn would help in various ways to improve the standards of reproductive hygiene products.

This study evaluates the efficacy of the postbiotic Probio-Eco in alleviating constipation in humans and mice. A randomized, double-blind, placebo-controlled crossover trial involving 110 adults with chronic constipation (Rome IV criteria) demonstrates that a 3-week Probio-Eco intervention significantly improves constipation symptoms, stool straining, and worry scores. Gut microbiota and metabolomic analyses reveal modulations in specific gut microbiota, succinate, tryptophan derivatives, deoxycholate, propionate, butyrate, and cortisol, correlating with symptom relief. A loperamide-induced mouse model confirms that Probio-Eco and its bioactive components (succinate, 3-indoleacrylic acid, and 5-hydroxytryptophan) alleviate constipation by stimulating mucin-2 secretion, regulating intestinal transport hormones, and promoting anti-inflammatory responses. Multi-omics integration identifies key pathways, including succinate-short-chain fatty acid, tryptophan-5-hydroxytryptophan-serotonin, and tryptophan-3-indoleacrylic acid, driving intestinal homeostasis and motility. These findings highlight the comprehensive efficacy of Probio-Eco and provide robust evidence for its clinical application in constipation management. This study was registered at Chinese Clinical Trial Registry (ChiCTR2100054376).

This study demonstrates that Bacillus subtilis GDAAS-A32-derived postbiotics (BSP) enhance yogurt production by optimizing lactic acid bacteria (LAB) viability and functionality. BSP enhanced the growth kinetics and biomass accumulation of Streptococcus thermophilus and Lactobacillus bulgaricus in both an anaerobic and aerobic pure system. The addition of BSP significantly increased the viable cell counts of S. thermophilus and L. bulgaricus, milk-clotting activity, sensory properties, and extracellular polysaccharide content and improved the rheological properties. Moreover, BSP elevated viable counts of S. thermophilus and L. bulgaricus to 6.18 × 108 CFU/g and 1.03 × 108 CFU/g, respectively, by day 7-representing 11.3-fold and 9.3-fold increases versus controls at 20% supplementation. Metabolomic signatures confirmed peptidoglycan reinforcement and flavor enhancement. Mechanistically, BSP supplementation might reduce urate and H2O2 toxicity through NH3-mediated proton neutralization and oxygen scavenging, while establishing a pyrimidine salvage network and redirecting one-carbon metabolism, resulting in enhanced stress tolerance and significant improvements in bacterial viability.

Probiotics such as Lactobacillus and Bifidobacterium spp. have been shown to be critical for maintaining host homeostasis. In recent years, key compounds of postbiotics derived from probiotic metabolism and cellular secretion have been identified for their role in maintaining organ immunity and regulating intestinal inflammation. In particular, probiotic-derived extracellular vesicles (PEVs) can act as postbiotics, maintaining almost the same functional activity as probiotics. They also have strong biocompatibility and loading capacity to carry exogenous or parental active molecules to reach distal organs to play their roles. This provides a new direction for understanding the intrinsic microbiota-host communication mechanism. However, most current studies on PEVs are limited to their functional effects/benefits, and their specific physicochemical properties, composition, intrinsic mechanisms for maintaining host homeostasis, and possible threats remain to be explored. Here, we review and summarize the unique physicochemical properties of PEVs and their bioactivities and mechanisms in mediating microbiota-host communication, and elucidate the limitations of the current research on PEVs and their potential application as postbiotics.

Parabacteroides distasonis (Pd), a core member of the human gut microbiota, is enriched in centenarians, suggesting a potential role in promoting organismal resilience. While Pd supplementation has been shown to alleviate cancer and inflammatory diseases, its ability to mitigate the decline associated with aging remains unexplored. Here, we demonstrate that postbiotic Pd supplementation induces multiple beneficial effects in 18- and 26-month-old mice following three months of treatment. Pd-treated mice exhibit lower blood glucose levels and increased ketone body production. In the gut, Pd reduces colon shortening observed in aged control mice and decreases the inflammatory mediator NFκB, in the colonic mucosa. Microbiome analysis further reveals enhanced gut microbiota diversity in Pd-supplemented mice. Additionally, FITC-dextran permeability assays indicate improved intestinal barrier function. Cell culture experiments in HCT116 colon cell line show that Pd reduces oxygen consumption and promotes mitochondrial networking, accompanied by upregulation of PGC1α and CHOP, suggesting a mitohormetic response. Beyond metabolic and gut-related benefits, Pd supplementation enhances skeletal muscle strength in both 18- and 26-month-old mice. Proteomic analysis of gastrocnemius muscle reveals that Pd increases the expression of mitochondrial proteins associated with mitochondrial fitness and survival. Notably, Pd-supplemented mice challenged with a high-fat diet gain weight at a slower rate, while maintaining better skeletal muscle coordination and strength. In summary, our findings suggest that postbiotic Pd supplementation enhances metabolic health, reduces inflammation, improves mitochondrial function, and preserves muscle strength in aged mice. These results position Pd as a promising therapeutic tool for promoting healthy aging and combating aging-related diseases.

Immune checkpoint inhibitors (ICIs) constitute a major breakthrough in the field of cancer therapy; their use has resulted in improved outcomes across various tumour types. However, ICIs can cause a diverse range of immune-related adverse events (irAEs) that present a considerable challenge to the efficacy and safety of these treatments. The gut microbiota has been demonstrated to have a crucial role in modulating the tumour immune microenvironment and thus influences the effectiveness of ICIs. Accumulating evidence indicates that alterations in the composition and function of the gut microbiota are also associated with an increased risk of irAEs, particularly ICI-induced colitis. Indeed, these changes in the gut microbiota can contribute to the pathogenesis of irAEs. In this Review, we first summarize the current clinical challenges posed by irAEs. We then focus on reported correlations between alterations in the gut microbiota and irAEs, especially ICI-induced colitis, and postulate mechanisms by which these microbial changes influence the occurrence of irAEs. Finally, we highlight the potential value of gut microbial changes as biomarkers for predicting irAEs and discuss gut microbial interventions that might serve as new strategies for the management of irAEs, including faecal microbiota transplantation, probiotic, prebiotic and/or postbiotic supplements, and dietary modulations.

Short stature of children has captured extensive attention since it reflects the health status of children and affects physical and psychological health throughout children's life. Compelling evidences have revealed that gut microbiota plays a critical role in growth regulation through nutrient metabolism, inflammation modulation, and endocrine signaling. Bifidobacterium animalis subsp. lactis BL-11 (BL-11) is a probiotic strain with potential benefits for gut health and metabolic function, but its effect on growth promotion in children with mild growth delay has not been fully explored.

This study aimed to evaluate the effect of BL-11 supplementation on height velocity (HV) and annual growth rate (AGR) in 3- to 7-year-old children with below-average height using a self-controlled clinical trial design over a 3-month intervention period.

A total of 124 children aged 3-7 years with height in the 3rd to 25th percentiles (P3-P25) range and an AGR of <5 cm/year were enrolled. Each child received a daily dose of BL-11 for 3 months. Baseline height was measured before the intervention, and post-intervention height was recorded at the end of the 3-month period. The primary outcome was the change in HV and AGR and secondary outcomes included changes in height percentile.

After 3 months of BL-11 supplementation, the children showed a significant increase in HV, with a mean improvement of 2.23 cm/3-month (8.92 cm/year) compared to the pre-intervention rate of <5 cm/year (P value = 0.004). The height percentiles were also improved and about 55.88 % (19/34) children with height in P3-P10 shifted to P10-P25. No serious adverse events were reported.

Supplementation with Bifidobacterium animalis subsp. lactis BL-11 for 3 months significantly improved height velocity in 3- to 7-year-old children with below-average height. The findings suggest that BL-11 may be a safe and effective probiotic intervention for promoting growth in children with mild growth delay. Further long-term studies are warranted to confirm the durability and consistency of these effects.

The interest in employing cell components as well as metabolites obtained from varied probiotic strains is increasing because of the growing concern regarding safety issues related to live microbial cells. Numerous benefits over conventional probiotics will facilitate the implementation of postbiotics as feed supplements in poultry nutrition. The beneficial characteristics, such as immunomodulation and antibacterial action, point to the possibility of postbiotics improving host health by altering the physiology of the host and ameliorating the disease condition in poultry. As we proceed forward with the ultimate aim of lowering antibiotic use in poultry, maximising performance and maintaining poultry production will be reliant on the best mixes of diverse alternatives as postbiotics, together with appropriate farm management practices. Trials with emphasis on validating the health claims made by these bioactive compounds are highly necessary. Furthermore, the employment of postbiotics under challenging conditions in poultry needs to be explored. This review focuses on highlighting the aspects about postbiotics and its various biological effects on meat and egg production in the poultry industry.

The gut microbiota represents a rich and adaptive microbial network inhabiting the gastrointestinal tract, performing key functions in nutrient processing, immune response modulation, intestinal wall protection, and microbial defense. Its composition remains highly personalized and responsive to external influences, including lifestyle patterns, physical activity, body composition, and nutritional intake. The interactions of the gut microbiota with bodily systems are conventionally interpreted as broad systemic impacts on organ balance. Yet, emerging research-exemplified by the gut microbiota-brain axis-suggests the potential existence of more targeted and direct communication mechanisms. Dysbiosis, characterized by microbial ecosystem disturbance, generates multiple metabolic compounds capable of entering systemic circulation and reaching distant tissues, notably including ocular structures. This microbial imbalance has been associated with both systemic and localized conditions linked to eye disorders. Accumulating scientific evidence now supports the concept of a gut-retina axis, underscoring the significant role of microbiota disruption in generating various retinal pathologies. This review comprehensively investigates gut microbiota composition, functional dynamics, and dysbiosis-induced alterations, with specific focus on retinal interactions in age-related macular degeneration, diabetic retinopathy, glaucoma, and retinal artery occlusion. Moreover, the review explores microbiota-targeted therapeutic strategies, including precision nutritional interventions and microbial transplantation, as potential modulators of retinal disease progression.

With the gradual rise of antibiotic-free farming practices, the exploration of novel, green, and low-pollution alternatives to antibiotics has become one of the key research focus in the field of agricultural science. In the development of antibiotic alternatives, probiotics, particularly host-associated probiotics, have been found to play a significant role in enhancing the production performance of livestock and poultry. However, research on and application of probiotics specifically for meat pigeons remain relatively underdeveloped.

To assess and investigate the probiotic efficacy and mechanisms during homologous lactic acid bacteria (LAB) transplant to host-pigeons, LAB strains with good probiotic properties were isolated from the intestinal contents of 28-day-old Mimas pigeons. And then measured the production indexes, intestinal flora, and intestinal transcriptomics of the hosts after instillation of LAB strains.

A total of 360 at 1-day-old pigeons were randomly divided into four groups and gavaged 0.4 mL Ligilactobacillus salivarius S10 with concentration of 0, 108, 109, and 1010 CFU/mL, designated as the control group (CG), the low concentration group (LG), the medium concentration group (MG), and the high concentration group (HG), respectively.

The findings revealed that an optimal concentration of 109 CFU/mL L. salivarius S10, a dominant strain isolated and screened, enhanced the growth performance and intestinal development of young pigeons. 16S rRNA gene sequencing analysis demonstrated a significant increase in the abundance of Lactobacillus, Pantoea_A and Enterococcus_H and a significant reduction in the abundance of Clostridium_T in the pigeon ileum (p < 0.05) under selected concentration treatment. Transcriptomic profiling of the ileum revealed 1828 differentially expressed genes (DEGs) between CG and MG. Notably, DEGs involved in the MAPK signaling pathway, such as RAF1, PDGFRB, and ELK4, were significantly correlated with differential ileal bacteria, suggesting that modulation of intestinal flora can influence the expression of genes related to cell proliferation and differentiation in the ileum, which is potentially important in promoting the growth and development of pigeons.

Ligilactobacillus salivarius S10 possesses the potential to be used as a probiotic for pigeons, which can influence the expression of gut development-related DEGs by regulating the intestinal flora, and further improve the growth performance of pigeons. This research provides a scientific foundation for developing pigeon-specific probiotics and promotes healthy farming practices for meat pigeons. Furthermore, it opens new avenues for improving the economic efficiency of pigeon farming.

Microbially synthesized postbiotics have unique properties and advantages; however, systematic studies on the efficient production and biological functions of postbiotics from Bacillus subtilis are limited, which greatly restricts their applications. In this study, we obtained a novel crude exopolysaccharide (EPS) postbiotic from Bacillus subtilis H4. We systematically optimized the EPS production strategy using single-factor analysis, Plackett-Burman design, the path of steepest ascent method, and response surface methodology. The optimized EPS yield was significantly improved, with a maximum yield of 15.01 g/L under the addition of 4.12% soy peptone, 8.99% sucrose, and 0.06% MnSO4. We found that EPS is a neutral, heterogeneous polysaccharide with a pyranose ring, with a molecular weight of 44,304.913 kDa and a melting point of 218 °C. It consists of glucose, galactose, arabinose, glucosamine, and mannose at a molar ratio of 58.85:19.81:14.75:10.89:6.58. EPS exhibits strong antioxidant capacities, scavenging ABTS and DPPH radicals with IC50 values of 1 and 6 mg/mL, respectively. Moreover, it shows notable anti-inflammatory properties, dramatically inhibiting the lipopolysaccharide (LPS)-induced elevation of nitric oxide (NO) levels and over-activation of the TLR4-NF-κB signaling pathway. These findings highlight the potential of EPS as a multifunctional bioactive compound, offering great promise for its application in the food, clinical, and feed industries.

Dysbiosis, characterized by a microbial imbalance, particularly within the gut microbiota, has emerged as a significant health concern linked to various diseases. This study analyzed 8097 patent documents from The Lens database (2005-2024) to examine global innovation trends in dysbiosis management. The patent filings showed exponential growth, peaking at 1222 documents in 2022, with the United States leading in publications (4361 documents). The analysis revealed three primary innovation clusters: bacterial-based therapeutics (44.8% of patents), specific therapeutic applications (27.6%), and diagnostic methods (15.9%). The disease associations predominantly included inflammatory conditions, infections, and cancer. The patent classifications highlighted a significant focus on probiotic development and microbiota modulation. The surge in patent activity since 2014 correlates with advances in DNA sequencing technology and the growing recognition of dysbiosis's role in human health. This analysis provides valuable insights into the evolving landscape of microbiome therapeutics and future directions for dysbiosis management.

Fermented foods have been consumed for millennia, valued for their extended shelf life, distinctive sensory properties, and potential health benefits. Emerging research suggests that fermented food consumption may contribute to gut microbiome diversity, immune modulation, and metabolic regulation; however, mechanistic insights and clinical validation remain limited. This review synthesizes current scientific evidence on the microbial and metabolite composition of fermented foods, their proposed health effects, and safety considerations for vulnerable populations. Additionally, we highlight the need for standardized definitions, serving sizes, and regulatory frameworks to enhance consumer transparency and research reproducibility. By providing a structured overview of existing data and knowledge gaps, this review establishes a foundation for integrating fermented foods into dietary recommendations and guiding future research directions.

Fruits and vegetables (FVs) are rich sources of macro and micro-nutrients crucial for a healthy diet. In addition to these nutrients, FVs also contain fibre and phytochemicals known for their antioxidant properties. Despite the growing evidence of the disease-preventive role of antioxidants in FVs, their bioavailability and bioaccessibility vary significantly and have not been adequately explored. Lactic acid bacterial (LAB) fermentation is considered the most appropriate and accessible biotechnological approach to maintain and enhance the safety, nutritional, sensory and shelf-life properties of perishable foods such as FVs. This review critically assesses how LAB fermentation could be utilised as a promising biotransformation strategy to enhance the bioavailability of antioxidants in FVs. Furthermore, it discusses the potential use of uniquely nutritious Australian native fruits as suitable candidates for LAB fermentation. Further research is essential to identify the beneficial properties of bioactive compounds and effective LAB-based biotransformation strategies to improve the bioavailability and bioaccessibility of antioxidants in FVs.

Cancer has long been associated with genetic and environmental factors, but recent studies reveal the important role of gut microbiota in its initiation and progression. Around 13% of cancers are linked to infectious agents, highlighting the need to identify the specific microorganisms involved. Gut microbiota can either promote or inhibit cancer growth by influencing oncogenic signaling pathways and altering immune responses. Dysbiosis can lead to cancer, while certain probiotics and their metabolites may help reestablish micro-ecological balance and improve anti-tumor immune responses. Research into targeted approaches that enhance therapy with probiotics is promising. However, the effects of probiotics in humans are complex and not yet fully understood. Additionally, methods to counteract harmful bacteria are still in development. Early clinical trials also indicate that modifying gut microbiota may help manage side effects of cancer treatments. Ongoing research is crucial to understand better how gut microbiota can be used to improve cancer prevention and treatment outcomes.

Everyday actions such as eating, tooth brushing or applying cosmetics inherently modulate our microbiome. Advances in sequencing technologies now facilitate detailed microbial profiling, driving intentional microbiome-targeted product development. Inspired by an academic-industry workshop held in January 2024, this review explores the oral, skin and gut microbiomes, focussing on the potential long-term implications of perturbations. Key challenges in microbiome safety assessment include confounding factors (ecological variability, host influences and external conditions like geography and diet) and biases from experimental measurements and bioinformatics analyses. The taxonomic composition of the microbiome has been associated with both health and disease, and perturbations like regular disruption of the dental biofilm are essential for preventing caries and inflammatory gum disease. However, further research is required to understand the potential long-term impacts of microbiome disturbances, particularly in vulnerable populations including infants. We propose that emerging technologies, such as omics technologies to characterize microbiome functions rather than taxa, leveraging artificial intelligence to interpret clinical study data and in vitro models to characterize and measure host-microbiome interaction endpoints, could all enhance the risk assessments. The workshop emphasized the importance of detailed documentation, transparency and openness in computational models to reduce uncertainties. Harmonisation of methods could help bridge regulatory gaps and streamline safety assessments but should remain flexible enough to allow innovation and technological advancements. Continued scientific collaboration and public engagement are critical for long-term microbiome monitoring, which is essential to advancing safety assessments of microbiome perturbations.

It is now well-established that exercise can disturb various aspects of gastrointestinal integrity and function. The pathophysiology of these perturbations, termed "exercise-induced gastrointestinal syndrome (EIGS)," can lead to exercise-associated gastrointestinal symptom (Ex-GIS) inconveniences. EIGS outcomes can impact physical performance and may lead to clinical manifestation warranting medical intervention, as well as systemic responses leading to fatality. Athlete support practitioners seek prevention and management strategies for EIGS and Ex-GIS. This current position statement aimed to critically appraise the role of EIGS and Ex-GIS prevention and management strategies to inform effective evidence-based practice and establish translational application. Intervention strategies with mostly consistent beneficial outcomes include macronutrient (i.e., carbohydrate and protein) intake and euhydration before and during exercise, dietary manipulation of fermentable oligo-, di-, and mono-saccharides and polyols (FODMAP), and gut training or feeding tolerance adjustments for the specific management of Ex-GIS from gastrointestinal functional issues. Strategies that may provide benefit and/or promising outcomes, but warrant further explorations include heat mitigating strategies and certain nutritional supplementation (i.e., prebiotics and phenols). Interventions that have reported negative outcomes included low-carbohydrate high-fat diets, probiotic supplementation, pharmaceutical administration, and feeding intolerances. Owing to individual variability in EIGS and Ex-GIS outcomes, athletes suffering from EIGS and/or support practitioners that guide athletes through managing EIGS, are encouraged to undertake gastrointestinal assessment during exercise to identify underlying causal and exacerbation factor/s, and adopt evidence-based strategies that provide individualized beneficial outcomes. In addition, abstaining from prevention and management strategies that present unclear and/or adverse outcomes is recommended.

The gut microbiome has a crucial role in cancer development and therapy through its interactions with the immune system and tumour microenvironment. Although evidence links gut microbiota composition to cancer progression, its precise role in modulating treatment responses remains unclear. In this Review, we summarize current knowledge on the gut microbiome's involvement in cancer, covering its role in tumour initiation and progression, interactions with chemotherapy, radiotherapy and targeted therapies, and its influence on cancer immunotherapy. We discuss the impact of microbial metabolites on immune responses, the relationship between specific bacterial species and treatment outcomes, and potential microbiota-based therapeutic strategies, including dietary interventions, probiotics and faecal microbiota transplantation. Understanding these complex microbiota-immune interactions is critical for optimizing cancer therapies. Future research should focus on defining microbial signatures associated with treatment success and developing targeted microbiome modulation strategies to enhance patient outcomes.

Microbial communities are not simply remnants of the past but dynamic entities that continuously evolve under the selective pressures of nature, reflecting the intricate and adaptive processes of evolution. The microbiota residing in the various regions of the human body has numerous roles in different physiological processes such as nutrition, metabolism, immune regulation, etc. In the zeal of achieving empirical insights into the ambit of the gut microbiome, the research over the years led to the revelation of reciprocal interaction between the gut microbiome and the cognitive functioning of the human body. Dysbiosis in the gut microbial composition disturbs the homeostatic cognitive functioning of the human body. This dysbiosis has been associated with various chronic diseases, including brain cancer, such as glioma, glioblastoma, etc. This review explores the mechanistic role of dysbiosis-mediated progression of brain cancers and their subtypes. Moreover, it demonstrates the regulatory role of microbial metabolites produced by the gut microbiota, such as short-chain fatty acids, amino acids, lipids, etc., in the tumour progression. Further, we also provide valuable insights into the microbiota mediating the efficiency of therapeutic regimens, thereby leveraging gut microbiota as potential biomarkers and targets for improved treatment outcomes.

The role of the gut-liver axis in liver cirrhosis is becoming increasingly recognized. We investigated the fecal microbiome in patients with liver cirrhosis and its potential function as a predictive biomarker of hepatic encephalopathy.

Patients were divided into either a high plasma ammonia (HPA) group or a low plasma ammonia (LPA) group according to the upper limit of normal of plasma ammonia concentration. 16S rRNA sequencing of fecal samples was performed to study how the microbiota affects the clinical symptoms of liver cirrhosis. The Stroop test was used to assess the ability of the brain to inhibit habitual behaviors.

Totally, 21 subjects were enrolled. Among the 18 patients with liver cirrhosis, 14 were male, the age range was 42-56 years, and the plasma ammonia level range was 20-125.9 μmol/l. The Stroop test showed more severe cognitive impairment in HPA than in LPA individuals. At the same time, there were significant differences in fecal microbiome characteristics between the two groups, characterized by a further increase in the abundance of the Proteobacteria phylum in the gut (especially aerobic Enterobacteriaceae ). Function predictions of Phylogenetic Investigation of Communities by Reconstruction of Unobserved States in the microbiome further explained the increase in the Enterobacteriaceae -dominated polyamine synthesis pathway in the gut microbiome of HPA groups.

Cirrhotic patients with hyperammonemia have a specific fecal bacterial composition (characterized via expansion of Enterobacteriaceae ). The ability to bio-synthesize polyamines that Enterobacteriaceae possesses is likely to be a key factor in the elevation of plasma ammonia.

With growing recognition of the pivotal role of gut microbiota in human health, probiotics have gained widespread attention for their potential to restore microbial homeostasis. However, a critical challenge persists: limited colonization efficiency among most probiotic strains compromises their therapeutic efficacy. This overview synthesizes ecological principles with cutting-edge microbiome research to elucidate the dynamic interplay between dietary components and probiotic colonization within the intestinal niche. This overview systematically analyzes: (1) stage-specific colonization mechanisms spanning microbial introduction, establishment, and proliferation; (2) nutrient-driven modulation of gut microbiota composition and function; and (3) the dual role of common dietary patterns as both facilitators and disruptors of probiotic persistence. Notably, this overview identifies key dietary strategies, including precision delivery of prebiotic fibers and polyphenol-microbiota crosstalk, that enhance niche adaptation through pH optimization, adhesion potentiation, and competitive exclusion of pathogens. Furthermore, this overview critically evaluates current limitations in probiotic research, particularly strain-specific variability and methodological constraints in simulating host-microbe-diet tripartite interactions. To bridge these gaps, this overview proposes an interdisciplinary framework integrating omics-driven strain selection, engineered delivery systems, and personalized nutrition models. Collectively, this work advances a mechanistic understanding of diet-microbiota interactions while providing actionable insights for developing targeted probiotic therapies and evidence-based dietary interventions to optimize gut ecosystem resilience.

Previous research shown that live probiotics have immunomodulatory effects, however the effectiveness of heat-inactivated bacteria and their immune-related components require further study. This study evaluated the immunomodulatory effects of heat-inactivated BBMN68 in BALB/c mice and explored immunomodulatory postbiotic components in vitro. Cyclophosphamide-induced immunosuppressed mice were orally administered heat-inactivated BBMN68 for 15 days. Postbiotic components from heat-inactivated BBMN68 were utilized to stimulate RAW264.7 cells for 24 h. In vivo, heat-inactivated BBMN68 significantly mitigated body weight decline, improved immune organ index and enhanced hematopoietic function in immunosuppressed mice. Additionally, it promoted delayed-type hypersensitivity responses and increased serum hemolysin and immunoglobulin (IgA, IgG, and IgM) levels. Oral administration of heat-inactivated BBMN68 increased serum cytokine (IL-2, TNF-α, IFN-γ, IL-4 and IL-6), while reducing IL-1β and IL-10. It also boosted beneficial microbiota (Lachnospiraceae_NK4A136_group and Dubosiella) and reduced harmful microbiota (Clostridium_sensu_stricto_1, Faecalibaculum and Romboutsia) by altering the Firmicutes/Bacteroidetes ratio. Unlike live probiotics, heat-inactivated BBMN68 is safer and has stronger immunomodulatory effects than Levamisole. It uniquely modulated gut microbiota compared to other heat-inactivated probiotics. In vitro, peptidoglycan from heat-inactivated BBMN68 cell wall suppressed TNF-α and IL-1β mRNA in RAW264.7 cells. These results suggest BBMN68 and its postbiotics can enhance immune responses, offering potential as safe immunomodulatory agents.

The gut-brain axis (GBA) is a bidirectional communication network between the gastrointestinal tract and the brain, modulated by gut microbiota and related biomarkers. Malnutrition disrupts GBA homeostasis, exacerbating GBA dysfunction through gut dysbiosis, impaired neuroactive metabolite production, and systemic inflammation. Nutraceuticals, including probiotics, prebiotics, synbiotics, postbiotics, and paraprobiotics, offer a promising approach to improving GBA homeostasis by modulating the gut microbiota composition and related neuroactive metabolites. This review aims to elucidate the interplay between gut microbiota-derived biomarkers and GBA dysfunction in malnutrition and evaluate the potential of nutraceuticals in combating malnutrition. Furthermore, it explores the future of personalised nutraceutical interventions tailored to individual genetic and microbiome profiles, providing a targeted approach to optimise health outcomes. The integration of nutraceuticals into GBA health management could transform malnutrition treatment and improve cognitive and metabolic health.

(Poly)phenols are bioactive compounds in plant-based foods with well documented health benefits. Their metabolism in dependent on gut microbiota composition, diversity, and function, which modulate their bioavailability and physiological effects. This review examines recent insights into (poly)phenol-gut microbiota interactions, emphasizing their relevance in mediating health benefits and mechanisms of action.

Recent studies have identified a high interindividual variability in (poly)phenol metabolism, explored microbial-derived metabolites with potential health benefits, and revealed bidirectional influences between (poly)phenols and gut microbiota composition. Advances in analytical techniques and large-scale studies have refined our understanding of these interactions, but inconsistencies remain in linking specific microbial signatures to health outcomes.

Standardized methodologies and long-term studies are needed to clarify the impact of (poly)phenol-derived metabolites on human health. Future research should focus on personalized and targeted nutrition approaches to optimize (poly)phenol benefits.

The human gut microbiome, composed of a vast array of microorganisms that have co-evolved with humans, is crucial for the development and function of brain systems. Research has consistently shown bidirectional communication between the gut and the brain through neuronal, endocrine, and immunological, and chemical pathways. Recent neuroscience studies have linked changes in the microbiome and microbial metabolites to various neuropsychiatric disorders such as autism, depression, anxiety, schizophrenia, eating disorders, and neurocognitive disorders. Novel metagenome-wide association studies have confirmed these microbiome variations in large samples and expanded our understanding of the interactions between human genes and the gut microbiome. The causal relationship between gut microbiota and neuropsychiatric disorders is being elucidated through the establishment of large cohort studies incorporating microbiome data and advanced statistical techniques. Ongoing animal and human studies focused on the microbiota-gut-brain axis are promising for developing new prevention and treatment strategies for neuropsychiatric conditions. The scope of these studies has broadened from microbiome-modulating therapies including prebiotics, probiotics, synbiotics and postbiotics to more extensive approaches such as fecal microbiota transplantation. Recent systematic reviews and meta-analyses have strengthened the evidence base for these innovative treatments. Despite extensive research over the past decade, many intriguing aspects still need to be elucidated regarding the role and therapeutic interventions of the microbiota-gut-brain axis in neuropsychiatric disorders.

Pediatric asthma, a prevalent chronic disease with rising global incidence, imposing substantial healthcare and socioeconomic burdens. Emerging evidence highlights the gut-lung axis as a pivotal therapeutic target, with microbiota dysbiosis implicated in immune dysregulation and airway hyperresponsiveness. This systematic review evaluated the efficacy and safety of probiotics, prebiotics, synbiotics, and postbiotics in pediatric asthma management.

A comprehensive search of PubMed, Cochrane library, Web of Science, and Embase was conducted up to 2nd January 2025. Inclusion criteria encompassed randomized controlled trials (RCTs) evaluating the therapeutic use of probiotics, prebiotics, synbiotics, or postbiotics in children and/or adolescents (<18 years) with asthma.

Eighteen studies (13 RCTs, n = 2,419 participants) were analyzed, focusing on children aged < 18 years. Probiotic interventions, predominantly Lactobacillus (5 studies) and Bifidobacterium (5 studies), demonstrated significant reductions in asthma exacerbations and improved pulmonary function, with strain-specific effects linked to Th2 cytokine suppression and gut-lung axis modulation. Postbiotics, including bacterial lysates (OM-85 BV, PMBL®), attenuated airway hyperresponsiveness and systemic inflammation. Synbiotics reduced viral respiratory infections and healthcare utilization. However, there is still a lack of direct RCTs to explore the therapeutic effects of prebiotics on pediatric asthma. Key limitations include methodological heterogeneity (dosing: 108-1010 CFU/day; duration: 8 weeks-12 months) and risk of bias (3 low-risk, 12 with concerns).

Our findings underscored the potential of microbiota-targeted therapies but highlight the need for standardized protocols, strain-specific trials, and pediatric prebiotic research. Future studies should integrate multi-omics to elucidate mechanisms and optimize personalized interventions.

https://www.crd.york.ac.uk/PROSPERO/view/CRD42025641318, identifier: CRD42025641318.

Atopic dermatitis (AD) is a complex immune-mediated disease characterised by recurrent eczematous lesions and pruritus, which adversely affects the quality of life (QoL). Genetic factors, environmental factors, immune dysregulation, and skin barrier dysfunction contribute to its pathophysiology. Non-pharmacological management strategies aim to preserve the skin barrier, address immune dysregulation, and minimise triggers. In this review, wediscuss various non-pharmacological interventions, including allergen (aeroallergens, food allergens, and contact allergens) avoidance, bathing-related measures, moisturisers, clothing choices, therapies targeting the skin microbiome, and allergen-specific immunotherapy, in addition to education and psychotherapy. Non-pharmacological therapies are essential for the holistic management of AD, but their effectiveness varies, highlighting the need for further research and tailored approaches to individual patient needs.

The increasing global prevalence of inflammatory diseases, such as ulcerative colitis and irritable bowel syndrome, represents a challenging task for healthcare systems. Several approaches to disease management target the intestinal microbiome, which plays a key role in health and disease. One promising approach is modulating the microbiome using human milk oligosaccharides (HMOs). Originating from human milk, HMOs are indigestible carbohydrates that act in a host-optimized prebiotic fashion by providing an energy source for health-promoting intestinal bacteria and exhibiting systemic effects. Commercial products supporting infant health and development have been the primary fields of HMO application. Advancements in the large-scale production of HMOs through bioengineering and precision fermentation have led to evaluation of their potential for managing inflammatory diseases. Several in vitro studies and observations on model systems have been clinically validated in infants, resulting in a large body of evidence supporting the safety and efficacy of HMOs in inflammatory disorders. Although novel approaches seek to explore interventions in adults, the primary goal for the future is to provide cost-efficient, safe, and reliable healthcare compounds across all age groups.

This study investigates the regenerative and protective effects of postbiotics (cell-free supernatant) derived from the Lactiplantibacillus plantarum EIR/IF-1 strain on human periodontal ligament mesenchymal stromal cells (hPDL-MSCs).

hPDL-MSCs were isolated from periodontal ligament tissues (PDL) of wisdom teeth using enzymatic digestion and subsequently characterized through immunophenotyping. The effect of postbiotics on the viability of hPDL-MSCs was assessed using the MTT assay and flow cytometry, while their impact on cell migration was evaluated via the scratch assay. Anti-inflammatory effects of postbiotics were investigated on lipopolysaccharide (LPS, derived from Porphyromonas gingivalis)-stimulated hPDL-MSCs through Enzyme-Linked Immunosorbent Assay (ELISA). Additionally, the antioxidant effects of postbiotics were analyzed in hydrogen peroxide (H₂O₂)-induced hPDL-MSCs by measuring reactive oxygen species (ROS) levels using flow cytometry. The expression of collagen type I (COL1A1) gene was further assessed by quantitative reverse transcription PCR and immunofluorescence staining.

Treatment with postbiotics (250 µg/mL) significantly increased the viability and migration capability of hPDL-MSCs, while enhancing collagen production for PDL repair. Treatment with postbiotics for 24 h resulted in a 54.53 ± 2.01% reduction in intracellular ROS levels compared to untreated H2O2-induced hPDL-MSCs. Furthermore, postbiotics significantly decreased the production of pro-inflammatory cytokines (IL-8, IL-6, and IL-1β), and increased the anti-inflammatory cytokine IL-10 (2.67-fold) compared to untreated LPS-stimulated hPDL-MSCs.

Our findings indicate that postbiotics exhibit biological activity throughout all stages of the healing process, beginning with the modulation of the inflammatory response to LPS stimulation, followed by the promotion of cell migration, proliferation, and collagen synthesis. Given the unmet need for safe and adjuvant therapeutic approaches that promote comprehensive periodontal regeneration in periodontal diseases, this study presents postbiotics as a promising candidate.

Postbiotics could be integrated into regenerative therapies as a novel bioactive material to improve the healing and regenerative outcomes in periodontal defects by both controlling inflammation and stimulating tissue repair processes.

Improving nitrogen utilization efficiency in ruminant livestock is vital for feeding a growing global population and lowering environmental pollution. The rumen and intestine harbor distinct epithelial structures and biogeographically stratified microbiota, and their co-oscillation assemblage patterns fulfill the pivotal role of metabolizing dietary nitrogen into bioavailable nutrients in ruminants. There is cursory evidence to suggest that an increased understanding of the spatial gastrointestinal microbiota‒host interactions will aid in the development of nutritional strategies to improve nitrogen utilization efficiency. In this review, we first explore the current knowledge on the processes of protein degradation, microbial protein synthesis, and urea nitrogen salvage in ruminal microorganisms and the epithelium. Second, we summarize the mechanisms of microbiota‒host interplay with regard to the amino acid utilization process in the intestine. Finally, we discuss the most pertinent and promising manipulation strategies that have emerged to balance food security and environmental impacts. In this review, we highlight the significance of leveraging gastrointestinal microbiota‒host co-oscillation patterns to improve nitrogen utilization efficiency, and put forward perspectives for future research opportunities that precisely target this coordinated interplay in the nitrogen metabolic network.

In our study, were evaluated effect on colorectal cancer cells of possible probiotic bacteria and new bioactive substances (paraprobiotics/postbiotics), miRNA-expression. Lactobacillus rhamnosus, Lactobacillus reuteri strains, HT-29, and Caco-2 were used. The cytotoxicity of the biotics was determined by MTT and miRNA expression. In line with the data obtained, it was determined that probiotics had a proliferative effect on the fibroblast cell line and a cytotoxic effect on cancer cells. It was observed that paraprobiotics had a minimal effect compared to probiotics, postbiotics had a greater effect. In this work, the activities of new pharmabiotics are compared with living cells, eliminating the limitations of probiotics in terms of shelf life and viability, and thus allowing the creation of new commercial domestic and national products, which increases the unique value of our study. In addition, there will be safer alternatives for suppressed immune systems, and various disadvantages of probiotics can be eliminated.

The current definition of a postbiotic is a "preparation of inanimate microorganisms and/or their components that confers a health benefit on the host". Postbiotics can be mainly classified as metabolites, derived from intestinal bacterial fermentation, or structural components, as intrinsic constituents of the microbial cell. Secondary bile acids deoxycholic acid (DCA) and lithocholic acid (LCA) are bacterial metabolites generated by the enzymatic modifications of primary bile acids by microbial enzymes. Secondary bile acids function as receptor ligands modulating the activity of a family of bile-acid-regulated receptors (BARRs), including GPBAR1, Vitamin D (VDR) receptor and RORγT expressed by various cell types within the entire human body. Secondary bile acids integrate the definition of postbiotics, exerting potential beneficial effects on human health given their ability to regulate multiple biological processes such as glucose metabolism, energy expenditure and inflammation/immunity. Although there is evidence that bile acids might be harmful to the intestine, most of this evidence does not account for intestinal dysbiosis. This review examines this novel conceptual framework of secondary bile acids as postbiotics and how these mediators participate in maintaining host health.

This comprehensive review explores the evolving role of probiotic-based foods and beverages, highlighting their potential as functional and "future foods" that could significantly enhance nutrition, health, and overall well-being. These products are gaining prominence for their benefits in gut health, immune support, and holistic wellness. However, their future success depends on addressing critical safety concerns and navigating administrative complexities. Ensuring that these products "do more good than harm" involves rigorous evaluations of probiotic strains, particularly those sourced from the human gastrointestinal tract. Lactic acid bacteria (LABs) serve as versatile and effective functional starter cultures for the development of probiotic foods and beverages. The review emphasizes the role of LABs as functional starter cultures and the development of precision probiotics in advancing these products. Establishing standardized guidelines and transparent practices is essential, requiring collaboration among regulatory bodies, industry stakeholders, and the scientific community. The review underscores the importance of innovation in developing "friendly bacteria," "super probiotics," precision fermentation, and effective safety assessments. The prospects of functional probiotic-based foods and beverages rely on refining these elements and adapting to emerging scientific advancements. Ultimately, empowering consumers with accurate information, fostering innovation, and maintaining stringent safety standards will shape the future of these products as trusted and beneficial components of a health-conscious society. Probiotic-based foods and beverages, often infused with LABs, a "friendly bacteria," are emerging as "super probiotics" and "future foods" designed to "do more good than harm" for overall health.

Lacticaseibacillus casei IDCC 3451 (3451) was evaluated for its effects on the gut-brain axis using Caenorhabditis elegans (C. elegans) and mouse models of stress and inflammation. In C. elegans, 3451 extended lifespans by 25 %, improved motility, and chemotaxis, enhanced survival under pathogen challenge, and reduced amyloid beta accumulation by 42 %. Transcriptomic profiling revealed upregulation of genes involved in neurotransmitter signaling and serine/threonine pathways. In the unpredictable chronic mild stress (UCMS) mouse model, 3451 administration increased the time spent in the center of the open field by 65 % and reduced immobility in the forced swim test by 32 %, indicating anxiolytic and antidepressant effects. Serum levels of aspartate aminotransferase (AST) and gamma-glutamyl transferase (GGT) were decreased by 18 % and 24 %, respectively. Additionally, 3451 restored the expressions of 5HT1AR, GABAR, and tight junction proteins, including ZO-1 and Claudin1. Metabolomic analysis showed increased glycine and decreased palmitic acid levels, associated with an increased abundance of Ruminococcus and Akkermansia. In the dextran sulfate sodium (DSS)-induced colitis model, 3451 reduced the disease activity index by 36 %, improved colon histology, increased goblet cell preservation, and upregulated ZO-1 and IL-10 expression. Threonine levels were also increased and correlated with a higher abundance of Coprococcus. These findings demonstrate that 3451 improved behavioral and intestinal outcomes through coordinated modulation of host signaling, metabolite production, and gut microbial composition, highlighting its therapeutic potential for managing IBD and neurobehavioral disorders.

Constipation is a common problem which often causes negative impacts on the patient's quality of life. Apart from the pharmacologic and diet approaches, the use of probiotics has gradually shown promising efficacy to alleviate constipation. However, an exact understanding of the underlying mechanisms of probiotic actions on alleviating constipation is still unclear and need to be explored. In this review, we propose a model, 'probiotics in human colon', from a bioprocess engineering perspective. This model can be interpreted as a new concept of bionic colonic bioreactor design of a human colon in vitro, in which the transport phenomena during the fermentation of chyme by probiotics can be detected. By reviewing the anatomy structure and peristalsis mode of the human colon, we have focused on the influence by probiotics on the physical properties of colonic contents during the fermentation process. We relate physical properties such as shape, water content, density, hardness, viscosity, and elasticity to constipation symptoms directly. The influences on the physical properties of colon contents triggered by probiotics can be a potential key to understand the mechanisms for alleviating constipation.

This review addresses critical gaps in knowledge and provides a literature overview of the molecular pathways connecting gut microbiota dysbiosis to increased intestinal permeability (commonly referred to as "leaky gut") and its contribution to metabolic disorders. Restoring a healthy gut microbiota holds significant potential for enhancing intestinal barrier function and metabolic health. These interventions offer promising therapeutic avenues for addressing leaky gut and its associated pathologies in metabolic syndrome.

In metabolic disorders such as obesity and type 2 diabetes (T2D), beneficial microbes such as those producing short-chain fatty acids (SCFAs) and other key metabolites like taurine, spermidine, glutamine, and indole derivatives are reduced. Concurrently, microbes that degrade toxic metabolites such as ethanolamine also decline, while proinflammatory, lipopolysaccharide (LPS)-enriched microbes increase. These microbial shifts place a higher burden on intestinal epithelial cells, which are in closest proximity to the gut lumen, inducing detrimental changes that compromise the structural and functional integrity of the intestinal barrier. Such changes include exacerbation of tight junction protein (TJP)s dysfunction, particularly through mechanisms such as destabilization of zona occludens (Zo)-1 mRNA or post-translational modifications. Emerging therapeutic strategies including ketogenic and Mediterranean diets, as well as probiotics, prebiotics, synbiotics, and postbiotics have demonstrated efficacy in restoring beneficial microbial populations, enhancing TJP expression and function, supporting gut barrier integrity, reducing leaky gut and inflammation, and ultimately improving metabolic disorders. This review summarizes the mechanisms by which gut microbiota contribute to the development of leaky gut and inflammation associated with metabolic syndrome. It also explores strategies for restoring gut microbiota balance and functionality by promoting beneficial microbes, increasing the production of beneficial metabolites, clearing toxic metabolites, and reducing the proportion of proinflammatory microbes. These approaches can alleviate the burden on intestinal epithelial cells, reduce leaky gut and inflammation, and improve metabolic health.

This study was performed to evaluate the effects of dietary supplementation with viable Bacillus subtilis, inactivated Lactobacillus plantarum, and their combination on growth and slaughter performance, immune organ and small intestine development, and cecal microbiota of broilers. A total of 480 one-day-old broilers were used across a 42-day feeding experiment and were fed a basal diet, a basal diet + 300 mg/kg viable B. subtilis (probiotic), 320 mg/kg heat-killed L. plantarum (postbiotic), or their mixtures (combination). Each diet had six replicates, and each replicate had 20 broilers. Compared to the control group, the final body weight and average daily gain increased, and the feed conversion ratio decreased in the probiotic and postbiotic groups, while the combination group showed parameters comparable to those of the postbiotic group. Feeding broilers with probiotic, postbiotic, and their combination increased the dressing-out percentage, indices of the spleen and bursa of Fabricius, and lengths and weights of the small intestine. In addition, the villus height/crypt depth ratio of both the duodenum and jejunum was increased in the probiotic and postbiotic groups. Broilers in the combination group had a lower abundance of Proteobacteria, while those in the probiotic and postbiotic groups had a higher abundance of Desulfovibrio in the cecum. Overall, we concluded that dietary supplementation with viable B. subtilis and inactivated L. plantarum could improve growth and slaughter performance, organ development, intestinal morphology, and cecal microbiota of broilers. However, their combination had not yielded a synergistic and additive effect on broilers.