Lactate-utilizing bacteria, isolated from human feces, that produce butyrate as a major fermentation product

Characteristics of volatile fatty acids production and microbial succession under acid fermentation via anaerobic membrane bioreactor treating kitchen waste slurry

In this study, two anaerobic membrane bioreactors (AnMBRs) were proceeded to produce volatile fatty acids (VFAs) from kitchen waste slurry under acidic conditions of pH 5 and 6. Higher fermentation potential and VFA quality were obtained at pH 6, with VFA production, yield and CODVFAs/CODeffluent ratio of 42.0 g/L, 0.4 g/g-CODinfluent and 80 % respectively. The alkali dosages during the stable operation at pH 5 and 6 were 0.03 g-NaOH/g-VFAs and 0.08 g-NaOH/g-VFAs respectively, far lower than that at pH 9 (0.4 g-NaOH/g-VFAs). The microbial community presented marked differences between pH 5 and 6. In addition, chemical cleaning and sludge discharge alleviated membrane fouling and ensured the stable membrane operation at pH 6, while these control strategies had no obvious improvement for fouling at pH 5 due to higher H+ toxicity. In short, pH 6 was more suitable for VFA production than pH 5 with AnMBR treating kitchen waste slurry.

Polyester-derived monomers as microbial feedstocks: Navigating the landscape of polyester upcycling

Since their large-scale adoption in the early 20th century, plastics have become indispensable to modern life. However, inadequate disposal and recycling methods have led to severe environmental consequences. While traditional end-of-life plastics management had predominantly relied on landfilling, a paradigm shift towards recycling and valorization emerged in the 1970s, leading to the development of various, mostly mechanochemical, recycling strategies, together with the more recent approach of biological depolymerization and upcycling. Plastic upcycling, which converts plastic waste into higher-value products, is gaining attention as a sustainable strategy to reduce environmental impact and reliance on virgin materials. Microbial plastic upcycling relies on efficient depolymerization methods to generate monomeric substrates, which are subsequently metabolized by native or engineered microbial systems yielding valuable bioproducts. This review focuses on the second phase of microbial polyester upcycling, examining the intracellular metabolic pathways that enable the assimilation and bioconversion of polyester-derived monomers into industrially relevant compounds. Both biodegradable and non-biodegradable polyesters with commercial significance are considered, with emphasis on pure monomeric feedstocks to elucidate intracellular carbon assimilation pathways. Understanding these metabolic processes provides a foundation for future metabolic engineering efforts, aiming to optimize microbial systems for efficient bioconversion of mixed plastic hydrolysates into valuable bioproducts.

From Gut to Skeletal Muscle: Synergistic Effects of Probiotics and Spirulina Supplementation on Soccer Players' Performance and Body Composition

Nutritional strategies are critical for optimizing soccer players' performance and body composition. Spirulina, a protein-rich plant-based supplement, and probiotics offer individual benefits. However, their combined effects remain underexplored. This study investigated the effects of co-supplementation with spirulina and probiotics on body composition, isokinetic, isometric strength, and performance metrics in male soccer players. In a double-blind, placebo-controlled trial, forty soccer players were randomly assigned to four groups: placebo (PLA), probiotics (PRO), spirulina (SPI), and combined probiotics-spirulina (PRO + SPI). The PRO group received two probiotic capsules (a total dose of 4.5 × 1011 CFU) daily, with breakfast and dinner. The SPI group consumed two 1-g spirulina tablets twice daily (2 g total), with breakfast and dinner. The PRO + SPI group received both supplements in the same dosing regimen, while the PLA group consumed starch-based placebo capsules. Over eight weeks, participants followed identical training regimens. Pre- and post-intervention assessments included body composition (weight, BMI, fat percentage, fat weight, muscle weight), performance metrics (vertical jump, agility, speed, anaerobic sprint tests), and isokinetic and isometric knee strength tests. Statistical analyses utilized repeated measures and Bonferroni post-hoc tests. The PRO + SPI group demonstrated more significant reductions in weight (P = 0.012) and fat weight (P = 0.001) compared to the PLA group, while the SPI group showed a significant reduction in fat percentage (P = 0.034). Agility scores improved significantly in the PRO + SPI group compared to the PLA (P = 0.001) and SPI (P = 0.004) groups. Isokinetic performance metrics, including average power during knee extension at 60°/s and 180°/s, improved significantly in the PRO + SPI group compared to the PLA group (P = 0.018 and P = 0.009, respectively). Similarly, the PRO and SPI groups outperformed the PLA group in isokinetic measures such as absolute peak torque at 60°/s (P = 0.032) and 180°/s (P = 0.006). Also, maximum voluntary isometric contraction (MVIC) improved significantly in the PRO and SPI groups compared to the PLA group (P = 0.001 for both). From gut to skeletal muscle, spirulina, and probiotic co-supplementation significantly enhanced body composition, reduced weight and fat mass, and improved agility and isokinetic strength compared to placebo or individual supplementation. These results emphasize the synergistic potential of this nutritional strategy for optimizing athletic performance and recovery, warranting further investigation across diverse athletic populations.

Complementary foods in infants: an in vitro study of the faecal microbial composition and organic acid production

The transition from breastmilk to complementary foods is critical for maturing the colonic microbiota of infants. Dietary choices at weaning can lead to long-lasting microbial changes, potentially influencing health later in life. However, the weaning phase remains underexplored in colonic microbiome research, and the current understanding of how complementary foods impact the infant's colonic microbiota is limited. To address this knowledge gap, this study assessed the influence of 13 food ingredients on the in vitro microbial composition and production of organic acids by the faecal microbiota in New Zealand infants aged 5 to 11 months. To better represent real feeding practices, ingredients were combined with infant formula, other complementary foods, or both infant formula and other foods. Among the individual food ingredients, fermentation with peeled kūmara (sweet potato) increased the production of lactate and the relative abundance of the genus Enterococcus. Fermentation with blackcurrants, strawberries, or raspberries enhanced acetate and propionate production. Additionally, fermentation with blackcurrants increased the relative abundance of the genus Parabacteroides, while raspberry fermentation increased the relative abundance of the genera Parabacteroides and Eubacterium. When combined with infant formula or with blackcurrants, fermenting black beans increased butyrate production and stimulated the relative abundance of Clostridium sensu stricto 1. These foods are promising candidates for future clinical trials.

Specific dietary fibers steer toward distal colonic saccharolytic fermentation using the microbiota of individuals with overweight/obesity

BACKGROUND

Evidence suggests that increased distal short-chain fatty acid (SCFA) production beneficially impacts metabolic health. However, indigestible carbohydrate availability is limited in the distal colon; consequently, microbes shift toward protein fermentation, often linked to adverse metabolic health effects. We aimed to identify specific fiber(s) that promote saccharolytic fermentation in the distal colon and thereby may (partially) inhibit proteolytic fermentation.

METHODS

Potato-fiber, pectin, and inulin were studied individually and in combination against a high (predigested) protein background using an in vitro model of the colon (TIM-2) inoculated with pooled, standardized fecal microbiota from individuals with overweight/obesity. Microbiota composition and activity were assessed at different timepoints to simulate the travel throughout the colon (proximal: 0-8 h, distal: 8-24 h) and compared to a high protein (HP)_control, receiving only proteins.

RESULTS

Fiber addition increased total SCFA production compared to HP_control (52.11 ± 1.49 vs 27.07 ± 0.26 mmol) whereas total branched-chain fatty acids (BCFA; a marker for protein fermentation) production only slightly decreased (3.31 ± 0.10 vs 4.18 ± 0.40 mmol). Combining potato-fiber and pectin led to the highest total and distal SCFA production and distal SCFA:BCFA. Fiber addition attenuated HP-induced increases in several bacterial taxa including Mogibacterium and Coprococcus, independent of fiber type. Additionally, time- and fiber-specific microbial signatures were identified: inulin increased Bifidobacterium (proximal) relative abundance and pectin and/or potato-fiber increased Prevotella 9 (distal) relative abundance.

CONCLUSION

The most marked increase in distal colonic SCFA production was induced by combining potato-fiber and pectin. Further research should elucidate whether this switch toward saccharolytic fermentation translates into beneficial metabolic health effects in humans.

Impact of flour particle size on digestibility and gut microbiota modulation in brown rice noodles: Balancing cell wall disruption and starch damage

Brown rice noodles are recognized for their health benefits. While previous research has focused on improving noodle properties through various processing conditions, the effects on digestibility and fermentability remain unclear. This study comprehensively investigated how brown rice flour particle size influences noodle digestibility and gut microbiota fermentation in vitro. Particle size first affects flour properties. The average particle size of BR15 flour (62 μm) falls between the length and width of the endosperm cells, effectively disrupting the cell walls while minimizing excessive starch damage, thus achieving an optimal balance and resulting in the highest peak viscosity. As a result, brown rice noodles made from BR15 flour exhibited the lowest starch digestibility in vitro. X-ray diffraction analysis revealed that starch crystals in digestive residues were predominantly V-type, with BR15 showing the highest relative crystallinity. In vitro fecal fermentation indicated elevated Bifidobacterium abundance and butyrate production for BR15 noodles compared to others. The moderate particle size of BR15 brown rice flour imparts unique digestibility and gut microbiota modulation to the noodles produced. This study provides insights into particle size optimization for improving nutritional quality of brown rice noodles.

Delayed Impact of Ionizing Radiation Depends on Sex: Integrative Metagenomics and Metabolomics Analysis of Rodent Colon Content

There is an escalating need to comprehend the long-term impacts of nuclear radiation exposure since the permeation of ionizing radiation has been frequent in our current societal framework. A system evaluation of the microbes that reside inside a host's colon could meet this knowledge gap since the microbes play major roles in a host's response to stress. Indeed, our past study suggested that these microbes might break their symbiotic association with moribund hosts to form a pro-survival condition exclusive to themselves. In this study, we undertook metagenomics and metabolomics assays regarding the descending colon content (DCC) of adult mice. DCCs were collected 1 month and 6 months after 7 Gy or 7.5 Gy total body irradiation (TBI). The assessment of the metagenomic diversity profile in DCC found a significant sex bias caused by TBI. Six months after 7.5 Gy TBI, decreased Bacteroidetes were replaced by increased Firmicutes in males, and these alterations were reflected in the functional analysis. For instance, a larger number of networks linked to small chain fatty acid (SCFA) synthesis and metabolism were inhibited in males than in females. Additionally, bioenergy networks showed regression dynamics in females at 6 months post-TBI. Increased accumulation of glucose and pyruvate, which are typical precursors of beneficial SCFAs coupled with the activated networks linked to the production of reactive oxygen species, suggest a cross-sex energy-deprived state. Overall, there was a major chronic adverse implication in male mice that supported the previous literature in suggesting females are more radioresistant than males. The sex-biased chronic effects of TBI should be taken into consideration in designing the pertinent therapeutics.

Short-Chain Fatty Acids Alleviate Perioperative Neurocognitive Disorders Through BDNF/PI3K/Akt Pathway in Middle-Aged Rats

Perioperative neurocognitive disorders (PND), characterized by persistent cognitive impairment lasting from days to years, present substantial clinical challenges in elderly surgical populations, profoundly compromising functional independence, quality of life, and long-term prognosis. We aimed to investigate the effects of short-chain fatty acids (SCFAs) treatment on PND via mediating Brain-derived neurotrophic factor (BDNF)/Phosphatidylinositol3-kinase (PI3K)/Protein kinase B (Akt) pathway. Using 16S rDNA sequencing targeting the V3-V4 hypervariable regions, we first demonstrated significant gut microbiota dysbiosis in PND model rats, accompanied by altered SCFAs profiles. Subsequent fecal microbiota transplantation (FMT) experiments established causal relationships between PND-associated microbial alterations and spatial cognitive deficits. Mechanistically, SCFAs supplementation attenuated neuronal damage and restored synaptic plasticity, as evidenced by Nissl staining quantification (reduced chromatolysis), TUNEL assay (decreased apoptosis rate), and immunohistochemical analysis (upregulated NeuN expression). Molecular investigations revealed that SCFAs-mediated cognitive improvement involved BDNF upregulation and subsequent PI3K/Akt pathway activation, ultimately enhancing neuronal survival and synaptic integrity. Notably, PND animals exhibited characteristic neuropathological features including synaptic density reduction (PSD-95 downregulation), neuroinflammation amplification (IL-6 elevation), and apoptosis activation-all significantly reversed by SCFA intervention. Our findings establish a novel gut-brain axis mechanism wherein microbiota-derived SCFAs may exert neuroprotection through BDNF-dependent PI3K/Akt signaling, and offer potential therapeutic strategies for PND management.

Ultrasonic degradation of mulberry twigs polysaccharides: Effect on in vitro hypoglycemic activity and prebiotic potential

This study aimed to enhance the in vitro hypoglycemic activity of mulberry twigs polysaccharides (MTP) through ultrasonic degradation and to elucidate its underlying mechanisms and prebiotic potential. The results demonstrated that ultrasonic degradation effectively increased its inhibitory activity against α-glucosidase. Structural characterization of MTP revealed that ultrasonic degradation significantly decreasing its molecular weight and monosaccharide composition. Mechanistic studies indicated that the inhibition of α-glucosidase by the degraded product MTP-240 was reversible and followed a single static quenching process. In vitro fermentation assays revealed that MTP-240 promoted the production of short-chain fatty acids (SCFAs), surpassing the inulin control, with pentanoic acid accumulating most substantially. Additionally, MTP-240 enhanced the growth of Bifidobacterium, a beneficial gut bacterium associated with improved glucose levels and antioxidant capacity. These findings suggested that ultrasonic degradation was an effective method for enhancing the glycosidase inhibitory activity of polysaccharides, and the degraded MTP possesses the potential to be developed as a food additive with dual functions of glycosidase inhibition and prebiotic activity. This research provides a theoretical basis for the further development of mulberry resources and related functional foods.

Bugs got milk? Exploring the potential of lactose as a prebiotic ingredient for the human gut microbiota of lactose-tolerant individuals

Milk consumption is important to help meet daily nutrient requirements. However, lactose-present in dairy products-has been associated with digestive discomfort in individuals who are lactose intolerant or have inadequate lactase activity. Yet, a new perspective on this dietary component has emerged: its potential as a prebiotic for the lactose-tolerant population. We hypothesized that ingestion of lactose may improve the microbial community structure and metabolism of the gut microbiota from healthy adults. First, we assessed the acute impact of lactose ingestion on the gut microbiota of adults using a short-duration in vitro batch colonic model. Subsequently, we employed a long-duration in vitro dynamic multivessel colonic model to evaluate the effects of lactose chronic ingestion. In both cases, a mixture of lactose/galactose/glucose was administered in a defined proportion to mimic lactose metabolism and galactose/glucose absorption in lactose-tolerant adults. The hypothesis was confirmed, as a modulatory prebiotic effect was revealed on the microbial community structure and metabolism of the microbiota upon treatments simulating the ingestion of three doses of lactose, equivalent to half a glass, one glass, and two glasses of cow's milk. The long-duration model confirmed this potential, increasing the relative abundance of the beneficial genera Lactobacillus, Akkermansia, and Faecalibacterium, while the usually detrimental genus Clostridium decreased. Additionally, the health-promoting microbial metabolites acetate, propionate, and lactate were increased. Therefore, lactose ingestion could positively modulate the gut microbiota in healthy lactose-tolerant adults, thereby promoting gut health and shedding light on the dietary benefits of consuming milk.

The modulatory effect of pea resistant starch on hyperlipidemia in high fat diet-induced obese mice is related to their supramolecular structural features

BACKGROUND

Resistant starch (RS) has gained attention for its potential in managing metabolic disorders. This study aimed to compare the supramolecular structure and anti-hyperlipidemia effects of RS isolated from native pea starch (NP-RS) and autoclaved pea starch (AP-RS) in high-fat diet (HFD)-induced obese mice. The structural characteristics of NP-RS and AP-RS were analyzed, and their impacts on obesity-related conditions, gene expression, and gut microbiota were evaluated.

RESULTS

The crystalline polymorph of AP-RS shifted from a C-type to a B-type, with significantly higher long- and short-range crystallinity and double helix levels compared to NP-RS, as determined by X-ray diffraction and solid-state carbon-13 nuclear magnetic resonance (13C-NMR) analyses. Small-angle X-ray scattering analysis demonstrated a higher α value for AP-RS, suggested enhanced structural compactness. In vivo experiments revealed that both NP-RS and AP-RS alleviated obesity-related conditions, including body weight control, oxidative stress inhibition, inflammatory response alleviation, and liver function regulation, with AP-RS exhibiting more pronounced effects. These effects were associated with the down-regulation of gene expression levels of liver type glycogen synthase-2 (GYS2), enzyme glycogenin-1 (GYG1), sterol regulatory element binding protein-1 (SREBP-1), fatty acid synthase (FAS) and the up-regulation of insulin induced gene-1 (Insig-1), Insig-2, and acetyl-CoA oxidase 1 (Acox1). Additionally, 16S rDNA sequencing analysis indicated that both NP-RS and AP-RS mitigated HFD-induced gut dysbiosis by increasing the abundance of beneficial bacteria, such as Allobaculum and Bifidobacterium.

CONCLUSION

The resistant characteristics of AP-RS, marked by increased crystallinity and a higher content of double helices, exhibit greater stability. This stability likely leads to differences in accessibility and fermentability between NP-RS and AP-RS substrates in vivo across various intestinal segments, resulting in different physiological responses in obese mice. These findings highlight the potential for designing novel RS-based supplements with tailored metabolic effects to promote health benefits. © 2025 Society of Chemical Industry.

Comparison of metagenomic analysis of fecal and gastrointestinal tract samples for identifying beneficial gut microorganisms

Introduction

Previous research on the gut microbiome has primarily focused on fecal microbiota, raising concerns about whether fecal samples accurately represent the entire intestinal microbiota. Studies have shown that microbial communities across the gastrointestinal (GI) tract are more diverse than those in feces, suggesting that microbial composition may vary depending on the sampling method. Additionally, analyzing the broader diversity of microbial communities in the GI tract may enhance the identification of potentially beneficial microbiota.

Methods

In this study, we compare gut microbiome datasets obtained from fecal samples and GI samples (collected by pooling luminal contents and mucosal scrapings from the stomach to the end of the colon) of 6-month-old mice using 16S rRNA sequencing. We further investigate the associations between gut microbiota and motor, cognitive, and emotional functions in mice, examining differences between the two sample types. To assess these variations, we apply DESeq2 analysis to identify microbial species enriched in high-functioning groups and evaluate how their selection may differ depending on the sampling approach.

Results

Our findings reveal notable differences in microbial composition between fecal and GI samples, suggesting that sampling methods may influence the identification of beneficial bacteria.

Discussion

These results highlight the importance of selecting an appropriate sampling approach in microbiome research to ensure a comprehensive understanding of gut microbiota-host interactions.

The Probiotic Strain Clostridium butyricum TO-A Produces Butyrate by Utilizing Lactate and Acetate

Lactate-utilizing bacteria (LUB) are intestinal bacteria that produce butyrate from lactate and acetate, key metabolites in the gut. As LUB help maintain lactate and butyrate concentrations in the intestinal tract, they are promising probiotic candidates. Clostridium butyricum TO-A (CBTOA) has reportedly been effective in treating various gastrointestinal issues in humans and animals. Although CBTOA is known to increase intestinal butyrate levels, it is unclear how it utilizes lactate and acetate, similar to LUB, to produce butyrate. We investigated lactate utilization-related genes in CBTOA and examined the relationship between lactate and acetate utilization and butyrate production using peptone-yeast medium supplemented with D-lactate, L-lactate, and/or acetate. This study demonstrates for the first time that the probiotic strain CBTOA harbors lactate utilization-related genes and efficiently produces butyrate only in the presence of exogenous lactate and acetate instead of sugars. Furthermore, CBTOA expresses a lactate racemase that enables the bacterium to utilize both lactate enantiomers while regulating the ratio of D-lactate to L-lactate in the intestinal microenvironment via racemization. In conclusion, CBTOA efficiently produces butyrate utilizing lactate and acetate, similar to LUB; therefore, CBTOA could be an efficient butyrate supplier as a probiotic strain in the intestinal tract.

Optimizing Precision Probiotics for Mitigating Graft-Versus-Host Disease

Precision probiotics have shown great promise as novel therapies but have not been fully realized. One major obstacle is that different strains of the same gut microbiota species can induce markedly variable phenotypic outcomes. Here, we aimed to optimize and validate in a preclinical model, a six-species precision probiotic therapy for graft-versus-host disease (GVHD), an autoimmune complication following allogeneic stem cell transplantation. We had identified these six species as associated with protection against GVHD in a prior clinical study. We isolated strains of three of the targeted taxa (B. longum, C. bolteae, and Blautia spp.) from human stem cell transplant patients and characterized their SCFA production in vitro. We observed significant strain-to-strain variability among these gut microbiota taxa in their capacity to produce short-chain fatty acids, a microbiota-derived metabolite shown to be important for mitigating gut GVHD and inflammatory bowel disease, in vitro. We found that B. longum was able to augment butyrate production by C. bolteae and Blautia when co-cultured in vitro. "Optimized" precision probiotics mitigated GVHD and significantly increased survival (p = 0.013, log-rank test) in mice compared to a "standard" probiotic consortium of the same bacterial species obtained from a commercial repository. Importantly, the optimized probiotics resulted in significant increases in intestinal short-chain fatty acid concentrations compared to standard probiotics (p < 0.001, Mann-Whitney test). Our findings highlight the promising potential of utilizing an optimized precision probiotic approach to maximize therapeutic efficacy.

Akkermansia muciniphila: promises and pitfallsfor next-generation beneficial microorganisms

Akkermansia muciniphila, a microorganism ubiquitously colonizing the mucosal layer of the human gut, has garnered significant scientific interest as a promising candidate for probiotic therapeutics. Its persistent identification in both laboratory and living organism studies underscores its potential physiological benefits, positioning it as a bacterium of paramount importance in promoting host health. This review examines the diversity and abundance of gut microbiota members, emphasizing the identification of microbial species engaged in cross-feeding networks with A. muciniphila. Insightful exploration into the mechanisms of cross-feeding, including mucin-derived nutrient exchange and metabolite production, unveils the intricate dynamics shaping microbial community stability. Such interactions contribute not only to the availability of essential nutrients within the gut environment but also to the production of metabolites influencing microbial community dynamics and host health. In conclusion, the cumulative evidence from in vitro and in vivo perspectives substantiates the notion that A. muciniphila holds tremendous promise as a next-generation probiotic. By leveraging its unique physiological benefits, particularly in mucosal health and metabolic regulation, A. muciniphila stands poised to revolutionize the landscape of probiotic interventions for enhanced host well-being.

The gut-brain axis and pain signalling mechanisms in the gastrointestinal tract

Visceral pain is a major clinical problem and one of the most common reasons patients with gastrointestinal disorders seek medical help. Peripheral sensory neurons that innervate the gut can detect noxious stimuli and send signals to the central nervous system that are perceived as pain. There is a bidirectional communication network between the gastrointestinal tract and the nervous system that mediates pain through the gut-brain axis. Sensory neurons detect mechanical and chemical stimuli within the intestinal tissues, and receive signals from immune cells, epithelial cells and the gut microbiota, which results in peripheral sensitization and visceral pain. This Review focuses on molecular communication between these non-neuronal cell types and neurons in visceral pain. These bidirectional interactions can be dysregulated during gastrointestinal diseases to exacerbate visceral pain. We outline the anatomical pathways involved in pain processing in the gut and how cell-cell communication is integrated into this gut-brain axis. Understanding how bidirectional communication between the gut and nervous system is altered during disease could provide new therapeutic targets for treating visceral pain.

Gut microbiota metabolites, secretory immunoglobulin A and Bayley-III cognitive scores in children from the CHILD Cohort Study

Background

Dysbiosis of the gut microbiota has been demonstrated in neurodevelopmental disorders but the underlying mechanisms that may explain these associations are poorly understood. Gut secretory immunoglobulin A (SIgA) binds pathogenic microbes, preventing mucosal penetration. Gut microbes also influence SIgA production and its binding characteristics through short-chain fatty acid (SCFA) metabolites, allowing them to regulate the immune response. Serum IgA deficiency has been noted in children with autism spectrum disorders (ASD). In this study, we aimed to determine whether SIgA level in infancy is associated with gut microbiota taxonomy and metabolites, and neurodevelopmental outcomes in preschool children.

Methods

For a subsample of 178 children from the Canadian CHILD Cohort Study, gut microbiota of fecal samples collected at 3-4 months and 12 months was profiled using 16S rRNA sequencing. Gut bacterial metabolites levels and SIgA level were measured by nuclear magnetic resonance (NMR) based metabolomics and SIgA enzyme-linked immunosorbent assay at 3-4 months, respectively. Bayley-III Scale of Infant Development was assessed at 12 and 24 months. We evaluated direct relationships in multiple linear regression models and putative causal relationships in statistical mediation models.

Results

Propionate and butyrate levels at 3-4 months were associated with decreased Bayley cognitive score at 24 months (p-values: 0.01 and 0.02, respectively) in adjusted multiple linear regression models, but when we investigated an indirect relationship mediated by decreased SIgA level at 3-4 months, it did not reach statistical significance (p-values: 0.18 and 0.20, respectively). Lactate level at 3-4 months was associated with increased Bayley cognitive score at 24 months in adjusted multiple linear regression models (p-value: 0.01), but the statistical model mediated by increased SIgA level at 3-4 months did not reach statistical significance neither (p-value: 0.20).

Conclusions

Our study contributes to growing evidence that neurodevelopment is influenced by the infant gut microbiota and that it might involve SIgA level, but larger studies are required.

Short chain fatty acids mediates complement C1q pathway alleviation of perioperative neurocognitive disorders

Perioperative neurocognitive disorders (PND) is one of the most common postoperative complications, which can lead to a harmful impact on self-dependence, longer hospital stays, increased medical costs, morbidity, and mortality amongst older adults. Microglia can modulate synapse elimination involved in the complement component protein 1q (C1q) pathway to induce cognitive dysfunction, which is significantly improved by short chain fatty acids (SCFAs) treatment. Here we investigate the effects of SCFAs treatment on PND via mediating C1q complement pathway. High-throughput sequencing of 16S rDNA from fecal samples of male SD rats was applied to assess the changes in gut microbiota. Fecal microbiota transplantation (FMT) was performed to investigate whether gut microbiota from PND rats could alter cognitive impairment. The blood from the rat tail vein was collected to measure the SCFAs concentrations. Hippocampal and brain tissue samples were obtained to perform Western blots, Golgi and immunofluorescence staining. Primary microglia treated with SCFAs or Histone deacetylase inhibitor were cultured to measure microglial activation states and the expression of acetylated histone. The 16S rDNA sequencing results showed that PND rats had the significant changes in the species diversity of the gut microbiota and the metabolite of specifc species. Gut microbiota from PND rats could alter spatial learning and memory, and meanwhile, the changed SCFAs concentrations in plasma were involved. The synapse elimination in PND rats was strikingly reversed by SCFAs treatment involved in modulation complement C1q via suppressing neuroinflammation. This suggests that a link between gut microbiota dysbiosis and cognitive function impairment is involved in synapse elimination via mediating complement C1q pathway. SCFAs treatment can alleviate PND, the mechanisms of which may be associated with regulating complement C1q pathway.

Fecal microbiota transplantation to prevent acute graft-versus-host disease: pre-planned interim analysis of donor effect

Gut microbiota disruptions after allogeneic hematopoietic cell transplantation (alloHCT) are associated with increased risk of acute graft-versus-host disease (aGVHD). We designed a randomized, double-blind placebo-controlled trial to test whether healthy-donor fecal microbiota transplantation (FMT) early after alloHCT reduces the incidence of severe aGVHD. Here, we report the results from the single-arm run-in phase which identified the best of 3 stool donors for the randomized phase. The primary and key secondary endpoints were microbiota engraftment and severe aGVHD, respectively. Three cohorts of patients (20 total) received FMT, each from a different donor. FMT was safe and effective in restoring microbiota diversity and commensal species. Microbiota engraftment, determined from shotgun sequencing data, correlated with larger microbiota compositional shifts toward donor and better clinical outcomes. Donor 3 yielded a median engraftment rate of 66%, higher than donors 1 (P = 0.02) and 2 (P = 0.03) in multivariable analysis. Three patients developed severe aGVHD; all 3 had received FMT from donor 1. Donor 3 was selected as the sole donor for the randomized phase. Our findings suggest a clinically relevant donor effect and demonstrate feasibility of evidence-based donor selection. FMT is a holistic microbiota restoration approach that can be performed as a precision therapeutic. ClinicalTrials.gov identifier NCT06026371.

Diabetes and gut microbiome

Diabetes mellitus represents a significant global health problem. The number of people suffering from this metabolic disease is constantly rising and although the incidence is heterogeneous depending on region, country, economic situation, lifestyle, diet and level of medical care, it is increasing worldwide, especially among youths and children, mainly due to lifestyle and environmental changes. The pathogenesis of the two most common subtypes of diabetes mellitus, type 1 (T1DM) and type 2 (T2DM), is substantially different, so each form is characterized by a different causation, etiology, pathophysiology, presentation, and treatment. Research in recent decades increasingly indicates the potential role of the gut microbiome in the initiation, development, and progression of this disease. Intestinal microbes and their fermentation products have an important impact on host metabolism, immune system, nutrient digestion and absorption, gut barrier integrity and protection against pathogens. This review summarizes the current evidence on the changes in gut microbial populations in both types of diabetes mellitus. Attention is focused on changes in the abundance of specific bacterial groups at different taxonomic levels in humans, and microbiome shift is also assessed in relation to geographic location, age, diet and antidiabetic drug. The causal relationship between gut bacteria and diabetes is still unclear, and future studies applying new methodological approaches to a broader range of microorganisms inhabiting the digestive tract are urgently needed. This would not only provide a better understanding of the role of the gut microbiome in this metabolic disease, but also the use of beneficial bacterial species in the form of probiotics for the treatment of diabetes.

A data-driven modeling framework for mapping genotypes to synthetic microbial community functions

Microbial communities play a central role in transforming environments across Earth, driving both physical and chemical changes. By harnessing these capabilities, synthetic microbial communities, assembled from the bottom up, offer valuable insights into the mechanisms that govern community functions. These communities can also be tailored to produce desired outcomes, such as the synthesis of health-related metabolites or nitrogen fixation to improve plant productivity. Widely used computational models predict synthetic community functions using species abundances as inputs, making it impossible to predict the effects of species not included in the training data. We bridge this gap using a data-driven community genotype function (dCGF) model. By lifting the representation of each species to a high-dimensional genetic feature space, dCGF learns a mapping from community genetic feature matrices to community functions. We demonstrate that dCGF can accurately predict communities in a fixed environmental context that are composed in part or entirely from new species with known genetic features. In addition, dCGF facilitates the identification of species roles for a community function and hypotheses about how specific genetic features influence community functions. In sum, dCGF provides a new data-driven avenue for modeling synthetic microbial communities using genetic information, which could empower model-driven design of microbial communities.

Effects of dietary supplementation of myristic acid on jejunal mucosa-associated microbiota, mucosal immunity, and growth performance of nursery pigs

The objective of this study was to investigate the effects of myristic acid on jejunal mucosal microbiota, mucosal immunity, and growth performance of nursery pigs. Thirty-six pigs (6.6 ± 0.4 kg of body weight) were assigned to three treatments (n = 12) for 35 d in three phases: (NC) basal diet; (PC) NC + bacitracin; and (MA) NC + myristic acid compound. Pigs were euthanized to collect jejunal mucosa, jejunal tissues, and ileal digesta. The PC increased (p < 0.05) the relative abundance (RA) of Lactobacillus spp., and Bifidobacterium boum than the NC group. The MA increased (p < 0.05) RA of Bifidobacterium dentium and Megasphaera spp. than the NC group. The PC tended to decrease IL-8 (p = 0.053) and protein carbonyl (p = 0.075) whereas IgG (p = 0.051) and IL-8 (p = 0.090) in jejunal mucosa were decreased by the MA. The PC increased (p < 0.05) the villus height to crypt depth ratio than the NC group. Both bacitracin and myristic acid improved the intestinal health and growth performance of nursery pigs. Effects of bacitracin were rather immediate whereas the effects of myristic acid were obtained after a 3-week feeding.

Butyrate: A potential mediator of obesity and microbiome via different mechanisms of actions

Butyrate, a short-chain fatty acid, is a crucial product of gut microbial fermentation with significant implications for various metabolic and physiological processes. Dietary sources of butyrate are limited, primarily derived from the fermentation of dietary fibers by butyrate-producing gut bacteria. Butyrate exerts its effects primarily as a histone deacetylase (HDAC) inhibitor and through signaling pathways involving G protein-coupled receptors (GPCRs). Its diverse benefits include promoting gut health, enhancing energy metabolism, and potentially alleviating complications associated with obesity. However, the exact role of butyrate in obesity is still under investigation, with a limited number of human trials necessitating further research to determine its efficacy and safety profile. Moreover, butyrate impact on the gut-brain axis and its modulation of microbiome effect on behavior highlight its broader importance in regulating host physiology. A thorough understanding of the metabolic pathways and mechanisms of butyrate is essential for developing targeted interventions for metabolic disorders. Continued research is crucial to fully realize its therapeutic potential and optimize its clinical applications in human health. In summary, this review illuminates the multifaceted role of butyrate as a potential mediator of obesity and related metabolic changes.

The effect of exercise on depression and gut microbiota: Possible mechanisms

Exercise can effectively prevent and treat depression and anxiety, with gut microbiota playing a crucial role in this process. Studies have shown that exercise can influence the diversity and composition of gut microbiota, which in turn affects depression through immune, endocrine, and neural pathways in the gut-brain axis. The effectiveness of exercise varies based on its type, intensity, and duration, largely due to the different changes in gut microbiota. This article summarizes the possible mechanisms by which exercise affects gut microbiota and how gut microbiota influences depression. Additionally, we reviewed literature on the effects of exercise on depression at different intensities, types, and durations to provide a reference for future exercise-based therapies for depression.

The Bifidogenic Effect of 2'Fucosyllactose Is Driven by Age-Specific Bifidobacterium Species, Demonstrating Age as an Important Factor for Gut Microbiome Targeted Precision Medicine

BACKGROUND

The human gut microbiota develops in concordance with its host over a lifetime, resulting in age-related shifts in community structure and metabolic function. Little is known about whether these changes impact the community's response to microbiome-targeted therapeutics. Providing critical information on this subject, faecal microbiomes of subjects from six age groups, spanning from infancy to 70-year-old adults (n = six per age group) were harvested. The responses of these divergent communities to treatment with the human milk oligosaccharide 2'-fucosyllactose (2'FL), fructo-oligosaccharides (FOS), and lactose was investigated using the Ex vivo SIFR® technology that employs bioreactor fermentation and is validated to be predictive of clinical findings. Additionally, it was evaluated whether combining faecal microbiomes of a given age group into a single pooled microbiome produced similar results as the individual microbiomes.

RESULTS

First, marked age-dependent changes in community structure were identified. Bifidobacterium levels strongly declined as age increased, and Bifidobacterium species composition was age-dependent: B. longum, B. catenulatum/pseudocatenulatum, and B. adolescentis were most prevalent for breastfed infants, toddlers/children, and adults, respectively. Metabolomic analyses (LA-REIMS) demonstrated that these age-dependent differences particularly impacted treatment effects of 2'FL (more than FOS/lactose). Further analysis revealed that while 2'FL enhanced production of short-chain fatty acids (SCFAs) and exerted potent bifidogenic effects, regardless of age, the specific Bifidobacterium species enhanced by 2'FL, as well as subsequent cross-feeding interactions, were highly age-dependent. Furthermore, single-pooled microbiomes produced results that were indicative of the average treatment response for each age group. Nevertheless, pooled microbiomes had an artificially high diversity, thus overestimating treatment responses (especially for infants), did not recapitulate interindividual variation, and disallowed for the correlative analysis required to unravel mechanistic actions.

CONCLUSIONS

Age is an important factor in shaping the gut microbiome, with the dominant taxa and their metabolites changing over a lifetime. This divergence affects the response of the microbiota to therapeutics, demonstrated in this study using 2'FL. These results evidence the importance of screening across multiple age groups separately to provide granularity of how therapeutics impact the microbiome and, consequently, human health.

Differential Gut Microbiome Profiles in Long-Distance Endurance Cyclists and Runners

We recently have shown that the gut microbiota composition in female and male runners positively correlates with sports, and female runners show similar gut microbiome diversity to male runners. However, gut microbiota composition has not yet been fully investigated in other endurance athletes, such as cyclists. Therefore, in the current study, we investigated the gut microbiome profiles in competitive, non-professional female and male cyclists compared to what we have shown in runners. We aim to understand (1) whether the gut microbiome signature is sport-specific; (2) whether there is a microbiome difference between female and male cyclists and runners; and (3) whether the gut bacteria expressed in cyclists and runners correlates with exercise performance. Our study included 58 subjects: 18 cyclists (9 males), 22 runners (13 males), and 18 control subjects (9 males). Fecal samples were obtained and subjected to taxonomic analysis to assess the relative abundances of species across subjects based on 16S rRNA sequencing results. Both alpha and beta diversity of the bacterial communities were evaluated to identify compositional variations between the groups. Each participant completed a maximal oxygen consumption test and a time-to-exhaustion test at 85% of the measured VO2max. Cyclists performed the test on an SRM ergometer, while runners used a motorized treadmill. Blood lactate levels were measured at 5 min intervals throughout the time-to-exhaustion trials. Alpha diversity demonstrated a significant difference (p-adj < 0.001) between cyclists and runners. Male cyclists showed significantly lower alpha diversity than runners (p-adj < 0.001). The taxonomic analysis of gut microbiota composition between cyclists, runners, and controls showed a lower or higher abundance of fifteen different bacteria. In cyclists, there was a significant positive correlation between six bacteria, and in runners, there was a significant positive correlation between eight bacteria, with weekly training volume, time-to-exhaustion, VO2max, and blood lactate levels. This study suggests potential sport-specific characteristics in long-distance cyclists' and runners' gut microbiome signatures. These findings emphasize the differences in gut microbiota between cyclists and runners, probably due to the difference in physiological and biomechanical conditions related to the activity mode during each sport.

Short-Term Supplementation of Sauerkraut Induces Favorable Changes in the Gut Microbiota of Active Athletes: A Proof-of-Concept Study

BACKGROUND

Since the gut microbiota is important for athlete health and performance, its optimization is increasingly gaining attention in sports nutrition, for example, with whole fermented foods. Sauerkraut is a traditional fermented food rich in pro-, pre-, and postbiotics, which has not yet been investigated in the field of sports nutrition.

METHODS

To determine whether sauerkraut could be used for gut microbiota optimization in sports nutrition, a proof-of-concept study was conducted. The microbiota composition of organic pasteurized sauerkraut was analyzed, and then healthy active athletes were provided with the same sauerkraut for 10 days as an intervention. The effects of sauerkraut on the athlete's gut microbiota, laboratory parameters, and bowel function were assessed.

RESULTS

Significant changes in the gut microbiota composition were seen on taxonomic and functional levels, independent of baseline microbiota composition, even after short-term supplementation. Most notably, there was an increase in several health-promoting genera of the family Lachnospiraceae, as well as significant alterations in metabolic pathways regarding cell wall synthesis and the metabolism of nucleotide bases. An increase in the proportion of lymphocytes and a decrease in B12 vitamin levels was observed, as well as a risk of indigestion in certain athletes, which significantly resolved after seven days of supplementation in all athletes. It is unclear whether the observed effects are attributable to the sauerkraut's own microbiome or its pre- and postbiotics since it is a whole food.

CONCLUSIONS

Our study has demonstrated that the concept of whole fermented foods, such as sauerkraut, could potentially be feasible and effective in sports nutrition for gut microbiota optimization.

Bifidobacterium species serve as key gut microbiome regulators after intervention in gestational diabetes mellitus

Gut microbiome dysbiosis is associated with gestational diabetes mellitus (GDM), and its modulation represents a promising approach for enhancing glycemic control. In this study, we aimed to discover specific alterations in the gut microbiome through lifestyle management. We performed metagenome sequencing on fecal samples and measured short-chain fatty acid (SCFA) in plasma samples from 27 well-controlled GDM pregnancies before and after glycemic control. At the same time, 38 normal glucose tolerance (NGT) samples served as controls. Additionally, we employed two-sample Mendelian Randomization (MR) to validate our findings against Genome-Wide Association Study (GWAS) database. Our dynamic analysis revealed Bifidobacterium genus increased in GDM patients after intervention. The MR analysis confirmed that the family of Bifidobacteriaceae (OR 0.929, 95% CI, 0.886-0.975; P = 0.003) was the only negatively associated family with GDM. Further analysis indicated the increased abundance of Bifidobacterium species were negatively correlated with glycemic traits (Spearman rho mean - 0.32 ± 0.34) but positively correlated with plasma SCFA levels (Spearman rho mean 0.24 ± 0.19). Functional analysis revealed that the quorum-sensing pathway had the strongest effect on the ability of Bifidobacterium to promote glucose homeostasis (Spearman rho = -0.34), suggesting its role in regulating intestinal microbiota. Finally, the multivariable MR analysis demonstrated that two pathways, COLANSYN PWY and PWY 7323, responsible for cell surface compound synthesis in gram-negative bacteria, mediated 14.83% (P = 0.017) and 16.64% (P = 0.049) of the protective effects of Bifidobacteriaceae against GDM, respectively. In summary, Bifidobacterium is an effective gut microbiota regulator for GDM-related glucose homeostasis.

The effect of probiotics and casein supplementation on aerobic capacity parameters of male soccer players

BACKGROUND

In the realm of sports science, nutrition is a well-established pillar for athletes' training, performance, and post-workout recovery. However, the role of gut microbiota, often overlooked, is a novel and intriguing aspect that can significantly impact athletic performance. With this in mind, our study ventures into uncharted territory, investigating the effect of probiotic and casein supplementation on the aerobic capacity of male soccer players.

METHOD

A double-blinded and placebo-controlled study was conducted with 44 male soccer players (Age: 22.81 ± 2.76 yr, Height: 177.90 ± 6.75 cm, Weight: 67.42 ± 8.44 kg). The participants were subjected to the Bruce test in the beginning; then, they were randomly divided into four groups, each consisting of 11 people: probiotics (PRO), casein (CAS), probiotics with casein (PRO+CAS), and placebo (PLA). PRO group was given one probiotic capsule (containing strains of Lactiplantibacillus plantarum BP06, Lacticaseibacillus casei BP07, Lactobacillus acidophilus BA05, Lactobacillus delbrueckii BD08 bulgaricus, Bifidobacterium infantis BI04, Bifidobacterium longum BL03, Bifidobacterium breve BB02 and Streptococcus salivarius thermophilus BT01, with a total dose of 4.5 × 1011 CFU) during dinner, while the CAS group consumed 20 grams of casein powder 45 minutes before bed. The PRO+CAS group was given one probiotic capsule during dinner and 20 grams of casein powder 45 minutes before bed. The participants in the PLA group were given one red capsule (containing 5 grams of starch) during dinner. All participants were instructed to take the supplements only on training days, three times a week for four weeks. The maximal oxygen consumption (VO2max), Ventilatory Threshold (VT), Time-to-exhaustion (TTE), Respiratory Compensation Point (RCP), Isocapnic area Time (Time-IC), Isocapnic area oxygen consumption (VO2-IC), and Hypocapnic Hyperventilation area Time (Time-HHV), after the Bruce test were Measured. All data were analyzed using SPSS Windows software, mixed repeated measure ANOVA, and Bonferroni post hoc test at p < 0.05 level.

RESULTS

The current study's findings illustrated that, after the intervention, TTE (p = 0.01) and RCP (p = 0.01) were significantly improved in PRO+CAS compared to the PLA group. No significant difference was observed between PRO and PLA (p = 0.52), PRO and CAS (p = 0.999), PRO and PRO+CAS (p = 0.9), CAS and PLA (p = 0.65), CAS and PRO+CAS (p = 0.73) in TTE. In addition, no significant difference was observed between PRO and CAS (p = 0.999), PRO and PLA (p = 0.40), PRO and PRO+CAS (p = 0.999), CAS and PLA (p = 0.263), CAS and PRO+CAS (p = 0.999) in RCP. Time-HHV was significantly higher in PRO+CAS (p = 0.000) and CAS (p = 0.047) compared to the PLA group. However, no significant difference was observed in the Time-HHV between PRO and CAS (p = 0.999), PRO and PRO+CAS (p = 0.25), PRO and PLA (p = 0.12), and CAS and PRO+CAS (p = 0.57). Additionally, all the groups had no significant differences in VO2max, VT1, VO2-IC and Time-IC.

CONCLUSION

The findings showed that consuming probiotics and casein could relatively improve the aerobic capacity of male soccer players. Nevertheless, simultaneous consumption of probiotics and casein had a more pronounced effect on aerobic capacity indicators, especially TTE and Time-HHV.

Analyzing the gut microbiota and microbial-associated metabolites of tomato-based sauces

Red Cooked Sauce (RCS) and Red Raw Sauce (RRS) are a mixture of natural crops that have a promising content of bioactive compounds (BC). The aim was to determine the effect of the indigestible fraction (IF) during the colonic fermentation in RCS and RRS by studying the two-way relationship between gut microbiota composition and microbial metabolites produced from BC fermented in the TNO in vitro dynamic model of the human colon (TIM-2). Total BC in undigested and predigested RRS, 957 and 715 mg/100 g DW, respectively, was significantly higher (p < 0.05) than in the RCS, 571 and 406 mg/100 g DW, respectively. Catenibacterium and Holdemanella increased during RCS fermentation, while 13 genera showed a clear positive correlation with most microbial phenolic metabolites. Our findings suggest that the mechanisms, pathways, and enzymes involved in producing microbial metabolites exhibited uniqueness among bacterial taxa, even within shared genus/family classifications.

Gut microbiota changes in healthy individuals, obstructive sleep apnea patients, and patients treated using continuous positive airway pressure: a whole-genome metagenomic analysis

PURPOSE

This study investigated variations in gut microbiota among severe obstructive sleep apnea (OSA) patients and changes in gut microbiota after continuous positive airway pressure (CPAP) treatment.

METHOD

From November 2020 to August 2021, laboratory-based polysomnography (PSG) was used to measure sleep parameters in healthy controls, severe OSA patients, and severe OSA patients treated with CPAP for three months. A fully automated biochemical analyzer was used to evaluate routine blood tests and biochemical indicators. Whole-genome metagenomic analysis was used to determine the microbial composition of gut samples from all participants. The relationships between gut microbiota and hypertension were examined using correlation analysis.

RESULT

The relative abundances of Bacteroides, Firmicutes, and Parabacteroides were significantly lower at the species level. Enterobacterales and Turicibacter were significantly higher in participants with severe OSA than healthy controls. Negative correlations were identified between Bacteroides coprocola and systolic blood pressure (SBP) (r =  - 0.710, P = 0.003) and diastolic blood pressure (DBP) (r =  - 0.615, P = 0.015). Conversely, a positive correlation was found between Escherichia coli and SBP (r = 0.568, P = 0.027).

CONCLUSION

The metabolic pathways and gut microbiota differed significantly between the control group and individuals with severe OSA. Additionally, CPAP therapy substantially changed the metabolic pathways and gut microbial composition among patients diagnosed with severe OSA. Correlation analysis further revealed a strong association between Escherichia coli, Bacteroides coprocola, and blood pressure levels.

The Link Between the Gut Microbiome and Bone Metastasis

The gut microbiome is essential for regulating host metabolism, defending against pathogens, and shaping the host's immune system. Mounting evidence highlights that disruption in gut microbial communities significantly impacts cancer development and treatment. Moreover, tumor-associated microbiota, along with its metabolites and toxins, may contribute to cancer progression by promoting epithelial-to-mesenchymal transition, angiogenesis, and metastatic spread to distant organs. Bones, in particular, are common sites for metastasis due to a rich supply of growth and neovascularization factors and extensive blood flow, especially affecting patients with thyroid, prostate, breast, lung, and kidney cancers, where bone metastases severely reduce the quality of life. While the involvement of the gut microbiome in bone metastasis formation is still being explored, proposed mechanisms suggest that intestinal dysbiosis may alter the bone microenvironment via the gut-immune-bone axis, fostering a premetastatic niche and immunosuppressive milieu suitable for cancer cell colonization. Disruption in the delicate balance of bone modeling and remodeling may further create a favorable environment for metastatic growth. This review focuses on the link between beneficial or dysbiotic microbiome composition and bone homeostasis, as well as the role of the microbiome in bone metastasis development. It also provides an overview of clinical trials evaluating the impact of gut microbial community structure on bone parameters across various conditions or health-related issues. Dietary interventions and microbiota modulation via probiotics, prebiotics, and fecal microbiota transplantation help support bone health and might offer promising strategies for addressing bone-related complications in cancer.

Influence of dairy matrix on the prebiotic effects of inulin related to gut metabolic activity and bone health

Inulin is a well-recognized prebiotic ingredient established to modulate the gut microbiome and its metabolic functionality. However, little is known about how the food matrix interacts with the prebiotic efficacy of inulin. The aim of the present study was to investigate the interaction between the food matrix (milk vs. yogurt) and the gut microbiome modulatory effects of inulin and its influence on calcium bioavailability as reflected in bone mineralization. For this purpose, a 6-week dietary intervention was conducted in healthy young growing male rats (n = 36) which received a diet matrix that included: (1) milk, (2) milk supplemented with 5% inulin, (3) yogurt, or (4) yogurt supplemented with 5% inulin. All diets were limited in calcium content and provided a daily intake of 46 mg calcium per rat. We found that inulin fortification of a yogurt diet exerted a larger effect on gut fermentation as reflected in pH and the generation of acetate in the distal part of the intestine and feces compared with inulin fortification of milk. Inulin was also associated with a higher acetate concentration in plasma when supplied in yogurt compared with milk. No effects of inulin supplementation were found on bone parameters. In conclusion, the present study suggested that the prebiotic efficacy of inulin is higher when supplied in a fermented dairy product than milk. However, neither adding inulin to yogurt or milk affected bone mineralization or the bone structure.

The gut microbiome is associated with susceptibility to febrile malaria in Malian children

Malaria is a major public health problem, but many of the factors underlying the pathogenesis of this disease are not well understood, including protection from the development of febrile symptoms, which is observed in individuals residing in areas with moderate-to-high transmission by early adolescence. Here, we demonstrate that susceptibility to febrile malaria following Plasmodium falciparum infection is associated with the composition of the gut microbiome prior to the malaria season in 10-year-old Malian children, but not in younger children. Gnotobiotic mice colonized with the fecal samples of malaria-susceptible children were shown to have a significantly higher parasite burden following Plasmodium infection compared to gnotobiotic mice colonized with the fecal samples of malaria-resistant children. The fecal microbiome of the susceptible children was determined to be enriched for bacteria associated with inflammation, mucin degradation and gut permeability, and to have increased levels of nitric oxide-derived DNA adducts and lower levels of mucus phospholipids compared to the resistant children. Overall, these results indicate that the composition of the gut microbiome is associated with the prospective risk of febrile malaria in Malian children and suggest that modulation of the gut microbiome could decrease malaria morbidity in endemic areas.

Dietary pectin and inulin: A promising adjuvant supplement for collagen-induced arthritis through gut microbiome restoration and CD4+ T cell reconstitution

Dietary strategies rich in fiber have been demonstrated to offer benefits to individuals afflicted with rheumatoid arthritis (RA). However, the specific mechanisms through which a high-fiber diet (HFD) mitigates RA's autoimmunity remain elusive. Herein, we investigate the influence of pectin- and inulin-rich HFD on collagen-induced arthritis (CIA). We establish that HFD significantly alleviates arthritis in CIA mice by regulating the Th17/Treg balance. The rectification of aberrant T cell differentiation by the HFD is linked to the modulation of gut microbiota, augmenting the abundance of butyrate in feces. Concurrently, adding butyrate to the drinking water mirrors the HFD's impact on ameliorating CIA, encompassing arthritis mitigation, regulating intestinal barrier integrity, and restoring the Th17/Treg equilibrium. Butyrate reshapes the metabolic profile of CD4+ T cells in an AMPK-dependent manner. Our research underscores the importance of dietary interventions in rectifying gut microbiota for RA management and offers an explanation of how diet-derived microbial metabolites influence RA's immune-inflammatory-reaction.

Interconnection of the Gut-Skin Axis in NC/Nga Mouse with Atopic Dermatitis: Effects of the Three Types of Bifidobacterium bifidum CBT-BF3 (Probiotics, Postbiotics, and Cytosine-Phosphate-Guanine Oligodeoxynucleotide) on T Cell Differentiation and Gut Microbiota

The gut microbiota is an immune system regulator in the gut-skin axis. Dysfunctional interactions between the gut microbiota and the gut immune system can lead to the development of skin diseases such as atopic dermatitis (AD). Probiotics and postbiotics positively affect the balance of the gut microbiota, immune regulation, protection against pathogens, and barrier integrity. This study investigated the effects of probiotic Bifidobacterium bifidum, postbiotic B. bifidum (heat-killed), and cytosine-phosphate-guanine oligodeoxynucleotide (CpG ODN) on the gut microbiota and T cell differentiation in NC/Nga mice induced with AD. 2,4-Dinitrochlorobenzene-induced AD mice had an increased SCORing atopic dermatitis-index and increased mRNA expression levels of Th2 and Th17 cell transcription factors and cytokines, and thymic stromal lymphopoietin (TSLP) cytokine in their mesenteric lymph nodes (mLNs; p<0.05). However, oral administration of the three types of B. bifidum (probiotics, postbiotics, CpG ODN) to AD mice decreased the mRNA expression levels of Th2 and Th17 cell transcription factors and cytokines as well as TSLP cytokine. They increased the mRNA expression levels of regulatory T (Treg) cell transcription factor and cytokine, galectin-9, and filaggrin genes (p<0.05). These effects were more noticeable in the mLNs than in the spleen. In addition, AD mice showed a decrease in Faecalibacterium prausnitzii, Roseburia spp., Leuconostoc citreum, Weissella cibaria, and Weissella koreensis (p<0.05). However, oral administration of the three types of B. bifidum increased Bacteroides spp., Bifidobacterium spp., F. prausnitzii, and Roseburia spp. (p<0.05).

Influence of gender, age, and body mass index on the gut microbiota of individuals from South China

Background

The symbiotic gut microbiota is pivotal for human health, with its composition linked to various diseases and metabolic disorders. Despite its significance, there remains a gap in systematically evaluating how host phenotypes, such as gender, age, and body mass index (BMI), influence gut microbiota.

Methodology/principal findings

We conducted an analysis of the gut microbiota of 185 Chinese adults based on whole-metagenome shotgun sequencing of fecal samples. Our investigation focused on assessing the effects of gender, age, and BMI on gut microbiota across three levels: diversity, gene/phylogenetic composition, and functional composition. Our findings suggest that these phenotypes have a minor impact on shaping the gut microbiome compared to enterotypes, they do not correlate significantly within- or between-sample diversity. We identified a substantial number of phenotype-associated genes and metagenomic linkage groups (MLGs), indicating variations in gut microflora composition. Specifically, we observed a decline in beneficial Firmicutes microbes, such as Eubacterium, Roseburia, Faecalibacterium and Ruminococcus spp., in both older individuals and those with higher BMI, while potentially harmful microbes like Erysipelotrichaceae, Subdoligranulum and Streptococcus spp. increased with age. Additionally, Blautia and Dorea spp. were found to increase with BMI, aligning with prior research. Surprisingly, individuals who were older or overweight exhibited a lack of Bacteroidetes, a dominant phylum in the human gut microbiota that includes opportunistic pathogens, while certain species of the well-known probiotics Bifidobacterium were enriched in these groups, suggesting a complex interplay of these bacteria warranting further investigation. Regarding gender, several gender-associated MLGs from Bacteroides, Parabacteroides, Clostridium and Akkermansia were enriched in females. Functional analysis revealed a multitude of phenotype-associated KEGG orthologs (KOs).

Conclusions/significance

Our study underscores the influence of gender, age, and BMI on gut metagenomes, affecting both phylogenetic and functional composition. However, further investigation is needed to elucidate the precise roles of these bacteria, including both pathogens and probiotics.

The associations between gut microbiota and fecal metabolites with intelligence quotient in preschoolers

BACKGROUND

The awareness of the association between the gut microbiota and human intelligence levels is increasing, but the findings are inconsistent. Furthermore, few research have explored the potential role of gut microbial metabolites in this association. This study aimed to investigate the associations of the gut microbiota and fecal metabolome with intelligence quotient (IQ) in preschoolers.

METHODS

The 16 S rRNA sequencing and widely targeted metabolomics were applied to analyze the gut microbiota and fecal metabolites of 150 children aged 3-6 years. The Wechsler Preschool and Primary Scale of Intelligence, Fourth Edition (WPPSI-IV) was used to assess the cognitive competence.

RESULTS

The observed species index, gut microbiome health index, and microbial dysbiosis index presented significant differences between children with full-scale IQ (FSIQ) below the borderline (G1) and those with average or above-average (all P < 0.05). The abundance of Acinetobacter, Blautia, Faecalibacterium, Prevotella_9, Subdoligranulum, Collinsella, Dialister, Holdemanella, and Methanobrevibacter was significantly associated with preschooler's WPPSI-IV scores (P < 0.05). In all, 87 differential metabolites were identified, mainly including amino acid and its metabolites, fatty acyl, and benzene and substituted derivatives. The differential fecal metabolites carnitine C20:1-OH, 4-hydroxydebrisoquine, pantothenol, creatine, N,N-bis(2-hydroxyethyl) dodecanamide, FFA(20:5), zerumbone, (R)-(-)-2-phenylpropionic acid, M-toluene acetic acid, trans-cinnamaldehyde, isonicotinic acid, val-arg, traumatin, and 3-methyl-4-hydroxybenzaldehyde were significantly associated with the preschooler's WPPSI-IV scores (P < 0.05). The combination of Acinetobacter, Isonicotinic acid, and 3-methyl-4-hydroxybenzaldehydenine may demonstrate increased discriminatory power for preschoolers in G1.

CONCLUSION

This study reveals a potential association between gut microbiome and metabolites with IQ in preschoolers, providing new directions for future research and practical applications. However, due to limitations such as the small sample size, unclear causality, and the complexity of metabolites, more validation studies are still needed to further elucidate the mechanisms and stability of these associations.

Soymilk yogurt fermented using Pediococcus pentosaceus TOKAI 759 m improves mice gut microbiota and reduces pro-inflammatory cytokine production

This study aimed to determine the anti-inflammatory activities and bioactive compounds of soymilk yogurt prepared using Lactiplantibacillus plantarum TOKAI 17 or Pediococcus pentosaceus TOKAI 759 m. Mice were divided into five groups: normal diet (ND), soymilk, soymilk yogurt using L. plantarum TOKAI 17 (SY 17) or P. pentosaceus TOKAI 759 m (SY 759 m), and 0.5 × 109 cells of each starter strain (BC 17 or BC759m). In the SY 759 m group, the serum pro-inflammatory cytokine levels and the cytotoxicity of natural killer cells were attenuated compared to the ND group. In the cecum microbiota, the abundances of butyrate-producing bacteria increased in the SY 759 m and BC 17 groups. Furthermore, SY 759 m metabolites contained high levels of aglycone isoflavone, adenine and showed a significant decrease in CCL-2 and interleukin-6 production in lipopolysaccharide-induced macrophage. In conclusion, soymilk yogurt produced using P. pentosaceus TOKAI 759 m modulates the gut microbiota and can potentially prevent pro-inflammatory cytokine production.

Potential Prebiotic Effects of Artemisia capillaris-Derived Transglycosylated Product

This study investigated the impact of a transglycosylated product (ACOD) catalyzed by Leuconostoc mesenteroides MKSR dextransucrase using sucrose as a glucosyl donor and both maltose and Artemisia capillaris as acceptors on gut microbiota through fecal fermentation. ACOD promoted the growth of probiotics such as Lactiplantibacillus plantarum, Lacticaseibacillus casei, Lacticaseibacillus rhamnosus GG, and Leuconostoc mesenteroides MKSR, while inhibiting the growth of pathogenic bacteria such as Escherichia coli, E. coli O157:H7, Enterococcus faecalis, Listeria monocytogenes, Staphylococcus aureus, Shigella flexneri, Streptococcus mutans, Pseudomonas aeruginosa, and Bacillus cereus during independent cultivation. Fecal fermentation for 24 h revealed that ACOD significantly increased the production of short-chain fatty acids (SCFAs) compared to the blank and fructoooligosaccharide (FOS) groups. Specifically, ACOD led to a 4.5-fold increase in acetic acid production compared to FOSs and a 3.3-fold increase in propionic acid production. Both the ACOD and FOS groups exhibited higher levels of butyric acid than the blank. Notably, ACOD significantly modulated the composition of the gut microbiota by increasing the relative abundances of Lactobacillus and decreasing Escherichia/Shigella and Salmonella. In contrast, FOSs remarkably promoted the growth of Salmonella. These findings suggest that ACOD is a potential candidate for prebiotics that improve the intestinal environment by being actively used by beneficial bacteria.

Lactiplantibacillus argentoratensis AGMB00912 alleviates diarrhea and promotes the growth performance of piglets during the weaning transition

BACKGROUND

Preventing post-weaning diarrhea (PWD) in weaned piglets is a crucial challenge in the swine production industry. The stress of weaning, dietary shifts from maternal milk to solid feed, and environmental changes lead to decreased microbial diversity, increased pathogen abundance, and compromised intestinal integrity. We have previously identified Lactiplantibacillus argentoratensis AGMB00912 (LA) in healthy porcine feces, which demonstrated antimicrobial activity against pathogens and enhanced short-chain fatty acid production. This research aimed to evaluate the efficacy of LA strain supplementation as a strategy to inhibit PWD and enhance overall growth performance in weaned piglets.

RESULTS

LA supplementation in weaned piglets significantly increased body weight gain, average daily gain, and average daily feed intake. It also alleviated diarrhea symptoms (diarrhea score and incidence). Notably, LA was found to enrich beneficial microbial populations (Lactobacillus, Anaerobutyricum, Roseburia, Lachnospiraceae, and Blautia) while reducing the abundance of harmful bacteria (Helicobacter and Campylobacter). This not only reduces the direct impact of pathogens but also improves the overall gut microbiota structure, thus enhancing the resilience of weaned piglets. LA treatment also promotes the growth of the small intestinal epithelial structure, strengthens gut barrier integrity, and increases short-chain fatty acid levels in the gut.

CONCLUSIONS

The study findings demonstrate the promising potential of LA in preventing PWD. Supplementation with the LA strain offers a promising feed additive for improving intestinal health and growth in piglets during the weaning transition, with the potential to significantly reduce the incidence and severity of PWD.

Thermophile-fermented feed modulates the gut microbiota related to lactate metabolism in pigs

AIMS

Extracts of fermented feed obtained via fermentation of marine animal resources with thermophilic Bacillaceae bacteria increase the fecundity of livestock. The intestinal bacterial profiles in response to long-term administration of this extract to pigs were investigated.

METHODS AND RESULTS

Half of a swine farm was supplied with potable water containing an extract of fermented feed for more than 2 years, whereas the other half was supplied with potable water without the extract. Feces from 6-month-old pigs rearing in these two areas were collected. 16S rRNA gene sequencing and isolation of lactic acid bacteria revealed an increase in the D/L-lactate-producing bacterium, Lactobacillus amylovorus, and a decrease in several members of Clostridiales following administration of fermented feed. A lactate-utilizing bacterium, Megasphaera elsdenii, was more abundant in the feces of pigs in the fermented feed group. All representative isolates of M. elsdenii showed rapid utilization of D-lactate relative to L-lactate, and butyrate and valerate were the main products.

CONCLUSION

The probiotic effect of fermented feed is associated with the modulation of lactate metabolism in the digestive organs of pigs.

Trait-based study predicts glycerol/diol dehydratases as a key function of the gut microbiota of hindgut-fermenting carnivores

BACKGROUND

Microbial pdu and cob-cbi-hem gene clusters encode the key enzyme glycerol/diol dehydratase (PduCDE), which mediates the transformation of dietary nutrients glycerol and 1,2-propanediol (1,2-PD) to a variety of metabolites, and enzymes for cobalamin synthesis, a co-factor and shared good of microbial communities. It was the aim of this study to relate pdu as a multipurpose functional trait to environmental conditions and microbial community composition. We collected fecal samples from wild animal species living in captivity with different gut physiology and diet (n = 55, in total 104 samples), determined occurrence and diversity of pdu and cob-cbi-hem using a novel approach combining metagenomics with quantification of metabolic and genetic biomarkers, and conducted in vitro fermentations to test for trait-based activity.

RESULTS

Fecal levels of the glycerol transformation product 1,3-propanediol (1,3-PD) were higher in hindgut than foregut fermenters. Gene-based analyses indicated that pduC harboring taxa are common feature of captive wild animal fecal microbiota that occur more frequently and at higher abundance in hindgut fermenters. Phylogenetic analysis of genomes reconstructed from metagenomic sequences identified captive wild animal fecal microbiota as taxonomically rich with a total of 4150 species and > 1800 novel species but pointed at only 56 species that at least partially harbored pdu and cbi-cob-hem. While taxonomic diversity was highest in fecal samples of foregut-fermenting herbivores, higher pduC abundance and higher diversity of pdu/cbi-cob-hem related to higher potential for glycerol and 1,2-PD utilization of the less diverse microbiota of hindgut-fermenting carnivores in vitro.

CONCLUSION

Our approach combining metabolite and gene biomarker analysis with metagenomics and phenotypic characterization identified Pdu as a common function of fecal microbiota of captive wild animals shared by few taxa and stratified the potential of fecal microbiota for glycerol/1,2-PD utilization and cobalamin synthesis depending on diet and physiology of the host. This trait-based study suggests that the ability to utilize glycerol/1,2-PD is a key function of hindgut-fermenting carnivores, which does not relate to overall community diversity but links to the potential for cobalamin formation. Video Abstract.

Analysis of the characteristics of intestinal microbiota in patients with different severity of obstructive sleep apnea

Intestinal microbiota imbalance plays an important role in the progression of obstructive sleep apnea (OSA), and is considered to be the main mediator that triggers metabolic comorbidities. Here, we analyzed the changes in intestinal microbiota in patients with different severities of OSA based on apnea hypopnea index (AHI) classification, and explored the role of intestinal microbiota in the severity of OSA. This study included 19 healthy volunteers and 45 patients with OSA [5 ≤ AHI < 15 (n = 14), 15 ≤ AHI < 30 (n = 13), AHI ≥ 30 (n = 18)]. Relevant sleep monitoring data and medical history data were collected, and microbial composition was analyzed using 16S rRNA high-throughput sequencing technology. The diversity analysis of intestinal microbiota among different groups of people was conducted, including alpha diversity, beta diversity, species diversity, and marker species as well as differential functional metabolic pathway prediction analysis. With the increase of AHI classification, the alpha diversity in patients with OSA significantly decreased. The results revealed that the severity of OSA is associated with differences in the structure and composition of the intestinal microbiota. The abundance of bacteria producing short-chain fatty acids (such as Bacteroides, Ruminococcacea, and Faecalibacterium) in severe OSA is significantly reduced and a higher ratio of Firmicutes to Bacteroidetes. Random forest analysis showed that Parabacteroides was a biomarker genus with important discriminatory significance. The differential metabolic pathway prediction function shows that the main function of maintaining intestinal microbiota homeostasis is biosynthetic function. Our results show that the differences in the composition of intestinal microbiota in patients with different severities of OSA are mainly related to short-chain fatty acid-producing bacteria. These changes may play a pathological role in OSA combined with metabolic comorbidities.

Multi-omics revealed the mechanism of feed efficiency in sheep by the combined action of the host and rumen microbiota

This study was conducted to investigate potential regulatory mechanisms of feed efficiency (FE) in sheep by linking rumen microbiota with its host by the multi-omics analysis. One hundred and ninety-eight hybrid female sheep (initial body weight = 30.88 ± 4.57 kg; 4-month-old) were selected as candidate sheep. Each test sheep was fed in an individual pen for 60 days, and the residual feed intake (RFI) was calculated. The ten candidate sheep with the highest RFI were divided into the Low-FE group, and the ten with the lowest RFI were divided into the High-FE group, all selected for sample collection. The RFI, average daily gain and average daily feed intake were highly significantly different between the two experimental groups (P < 0.05). Compared with Low-FE group, the insulin-like growth factor-1 and very low-density lipoprotein in serum and the propionate in rumen significantly increased in High-FE group (P < 0.01), but the acetate:propionate ratio in rumen significantly decreased in High-FE group (P = 0.034). Metagenomics revealed Selenomonas ruminantium, Selenomonas sp. and Faecalibacterium prausnitzi i were key bacteria, and increased abundance of the genes encoding the enzymes for cellulose degradation and production of propionate in High-FE group. The results of proteomics and section showed the rumen papilla length (P < 0.001) and expression of carbonic anhydrase and Na+/K+-ATPase were significantly higher in High-FE group (P < 0.05). On the other hand, the acetyl-CoA content significantly increased in the liver of High-FE group (P = 0.002). The relative expression levels of insulin-like growth factor-1 and apolipoprotein A4 genes were significantly up-regulated in the liver of High-FE group (P < 0.01), but relative expression level of monoacylglycerol O-acyltransferase 3 gene was significantly down-regulated (P = 0.037). These findings provide the mechanism by which the collaborative interaction between rumen microbiota fermentation and host uptake and metabolism of fermentation products impacts feed efficiency traits in sheep.

Lactobacillus acidophilus KBL409 protects against kidney injury via improving mitochondrial function with chronic kidney disease

PURPOSE

Recent advances have led to greater recognition of the role of mitochondrial dysfunction in the pathogenesis of chronic kidney disease (CKD). There has been evidence that CKD is also associated with dysbiosis. Here, we aimed to evaluate whether probiotic supplements can have protective effects against kidney injury via improving mitochondrial function.

METHODS

An animal model of CKD was induced by feeding C57BL/6 mice a diet containing 0.2% adenine. KBL409, a strain of Lactobacillus acidophilus, was administered via oral gavage at a dose of 1 × 109 CFU daily. To clarify the underlying mechanisms by which probiotics exert protective effects on mitochondria in CKD, primary mouse tubular epithelial cells stimulated with TGF-β and p-cresyl sulfate were administered with butyrate.

RESULTS

In CKD mice, PGC-1α and AMPK, key mitochondrial energy metabolism regulators, were down-regulated. In addition, mitochondrial dynamics shifted toward fission, the number of fragmented cristae increased, and mitochondrial mass decreased. These alterations were restored by KBL409 administration. KBL409 supplementation also improved defects in fatty acid oxidation and glycolysis and restored the suppressed enzyme levels involved in TCA cycle. Accordingly, there was a concomitant improvement in mitochondrial respiration and ATP production assessed by mitochondrial function assay. These favorable effects of KBL409 on mitochondria ultimately decreased kidney fibrosis in CKD mice. In vitro analyses with butyrate recapitulated the findings of animal study.

CONCLUSIONS

This study demonstrates that administration of the probiotic Lactobacillus acidophilus KBL409 protects against kidney injury via improving mitochondrial function.

Gut microbiota derived short-chain fatty acids in physiology and pathology: An update

Short-chain fatty acids (SCFAs) are essential molecules produced by gut bacteria that fuel intestinal cells and may also influence overall health. An imbalance of SCFAs can result in various acute and chronic diseases, including diabetes, obesity and colorectal cancer (CRC). This review delves into the multifaceted roles of SCFAs, including a brief discussion on their source and various gut-residing bacteria. Primary techniques used for detection of SCFAs, including gas chromatography, high-performance gas chromatography, nuclear magnetic resonance and capillary electrophoresis are also discussed through this article. This review study also compiles various synthesis pathways of SCFAs from diverse substrates such as sugar, acetone, ethanol and amino acids. The different pathways through which SCFAs enter cells for immune response regulation are also highlighted. A major emphasis is the discussion on diseases associated with SCFA dysregulation, such as anaemia, brain development, CRC, depression, obesity and diabetes. This includes exploring the relationship between SCFA levels across ethnicities and their connection with blood pressure and CRC. In conclusion, this review highlights the critical role of SCFAs in maintaining gut health and their implications in various diseases, emphasizing the need for further research on SCFA detection, synthesis and their potential as diagnostic biomarkers. Future studies of SCFAs will pave the way for the development of novel diagnostic tools and therapeutic strategies for optimizing gut health and preventing diseases associated with SCFA dysregulation.

Differential effects of pectin-based dietary fibre type and gut microbiota composition on in vitro fermentation outcomes

Interactions between human gut microbiota and dietary fibres (DF) are influenced by the complexity and diversity of both individual microbiota and sources of DF. Based on 480 in vitro fermentations, a full factorial experiment was performed with six faecal inocula representing two enterotypes and three DF sources with nanometer, micrometer, and millimeter length-scales (apple pectin, apple cell walls and apple particles) at two concentrations. Increasing DF size reduced substrate disappearance and fermentation rates but not biomass growth. Concentrated DF enhanced butyrate production and lactate cross-feeding. Enterotype differentiated final microbial compositions but not biomass or fermentation metabolite profiles. Individual donor microbiota differences did not influence DF type or concentration effects but were manifested in the promotion of different functional microbes within each population with the capacity to degrade the DF substrates. Overall, consistent effects (independent of donor microbiota variation) of DF type and concentration on kinetics of substrate degradation, microbial biomass production, gas kinetics and metabolite profiles were found, which can form the basis for informed design of DF for desired rates/sites and consequences of gut fermentation. These results add further evidence to the concept that, despite variations between individuals, the human gut microbiota represents a community with conserved emergent properties.

Next generation probiotics for human health: An emerging perspective

Over recent years, the scientific community has acknowledged the crucial role of certain microbial strains inhabiting the intestinal ecosystem in promoting human health, and participating in various beneficial functions for the host. These microorganisms are now referred to as next-generation probiotics and are currently considered as biotherapeutic products and food or nutraceutical supplements. However, the majority of next-generation probiotic candidates pose nutritional demands and exhibit high sensitivity towards aerobic conditions, leading to numerous technological hurdles in large-scale production. This underscores the need for the development of suitable delivery systems capable of enhancing the viability and functionality of these probiotic strains. Currently, potential candidates for next generation probiotics (NGP) are being sought among gut bacteria linked to health, which include strains from the genera Bacteroids, Faecalibacterium, Akkermansia and Clostridium. In contrast to Lactobacillus spp. and Bifidobacterium spp., NGP, particularly Bacteroids spp. and Clostridium spp., appear to exhibit greater ambiguity regarding their potential to induce infectious diseases. The present review provides a comprehensive overview of NGPs in terms of their health beneficial effects, regulation framework and risk assessment targeting relevant criteria for commercialization in food and pharmaceutical markets.

Oral Anaerobutyricum soehngenii augments glycemic control in type 2 diabetes

This randomized, double-blind, placebo-controlled trial investigated the impact of 14-day Anaerobutyricum soehngenii L2-7 supplementation on postprandial glucose levels in 25 White Dutch males with type 2 diabetes (T2D) on stable metformin therapy. The primary endpoint was the effect of A. soehngenii versus placebo on glucose excursions and variability as determined by continuous glucose monitoring. Secondary endpoints were changes in ambulatory 24-h blood pressure, incretins, circulating metabolites and excursions of plasma short-chain fatty acids (SCFAs) and bile acids upon a standardized meal. Results showed that A. soehngenii supplementation for 14 days significantly improved glycemic variability and mean arterial blood pressure, without notable changes in SCFAs, bile acids, incretin levels, or anthropometric parameters as compared to placebo-treated controls. Although well-tolerated and effective in improving glycemic control in the intervention group, further research in larger and more diverse populations is needed to generalize these findings.