Achieving cost-effective production of lignocellulosic biochemicals hinges on yeast's ability to utilize xylose efficiently. While Kluyveromyces marxianus is a natural xylose-fermenting yeast, its fermentation efficiency remains inadequate, particularly in conversion yield. This study aims to increase the efficiency of xylose utilization by employing adaptive laboratory evolution (ALE) to generate robust strains for single-cell proteins. After 20 batches of serial passaging culture, we successfully obtained an evolved strain, K. marxianus ZHY-3. ZHY-3 was cultured in a synthetic medium with xylose as the only carbon source in shake flasks. Compared with the wild-type ZHY-1, the specific growth rate increased by 3.5-fold, and the xylose yield coefficient increased by 78.6%. In addition, the specific growth rate of ZHY-3 in the glucose synthesis medium has also increased. In order to clarify its potential mechanism, we conducted a whole-genome analysis, and the results showed that in ZHY-3, phenotype-related single nucleotide polymorphisms (SNP) and insertion/deletion variations (InDel) exist in the mitogen-activated protein kinase (MAPK) signaling pathway and cell cycle process regulation related genes. These findings provide a potential strategic target for future metabolic engineering and show that ZHY-3 is a new candidate strain capable of utilizing lignocellulose biomass.

Limosilactobacillus reuteri (L. reuteri) has probiotic advantages such as suppressing pathogenic bacteria, balancing the gut microbiota, regulating immunity, and having anti-inflammatory and antioxidant properties. This study explored its potential antibacterial and anti-inflammatory properties, isolating the bacterium from healthy pig feces. L. reuteri ZY18 was chosen due to its superior acid production, tolerance, and antibacterial characteristics. In vitro, the ZY18 strain had a survival rate of 46.00

Background Obesity and related metabolic complications are associated with adipose tissue (AT) dysfunction, which contributes to metabolic inflexibility. However, the underlying mechanisms remain unclear. Our previous studies demonstrated that a high-fat diet (HFD) induces weight gain, increased fat weight, as well as significant metabolite alterations in serum, liver, and cecum in mice. Therefore, this study aims to investigate the effect of HFD on AT metabolites to elucidate their role in obesity progression. Methods To establish a diet-induced obesity model, nine female Kunming mice were fed a high-fat diet (HFD) for 16 weeks and compared with nine control mice maintained on a normal diet. Subcutaneous abdominal adipose tissue samples (SAAT) were analyzed using ultra-high-performance liquid chromatography-high-resolution mass spectrometry (UHPLC-HRMS) coupled with orthogonal partial least squares discriminant analysis (OPLS-DA). Results By metabolic profiling, 48 significantly different metabolites were identified, including phosphatidylcholines (PCs), lysophosphatidylcholines (LysoPCs), O-phosphoethanolamine, linoleic acid, alpha-linolenic acid, proline betaine, and 3-dehydroxycarnitine. These obesity-associated metabolites were mainly involved in glycerophospholipid metabolism, sphingolipid metabolism, and biosynthesis of unsaturated fatty acids. Among these pathways, glycerophospholipid metabolism exhibited the most pronounced disruption. Conclusions These identified metabolites in SAAT may aid in understanding of the mechanism by which HFD promotes the progression of obesity and related diseases.

The recalcitrant structure of lignocellulose hinders the efficient valorization of wheat straw. White-rot fungi have been extensively studied for their ability to completely degrade lignocellulose, yet the specific mechanisms remain insufficiently elucidated. In this study, the white-rot fungus Irpex lacteus QJ was applied to the solid-state fermentation of raw wheat straw (IW group) and NaOH-pretreated wheat straw (IN group). The degradation efficiency and mechanisms were investigated using enzyme activity assays, structural analyses (scanning electron microscopy, Fourier transform infrared spectroscopy, and X-ray diffraction), and multi-omics approaches. The results demonstrated that I. lacteus QJ effectively degraded wheat straw in both groups, and the IW group had significantly higher degradation rates of cellulose (56.21

Limosilactobacillus reuteri, a recognized probiotic, improves intestinal health in animals, but the mechanism remains unclear. This study investigates the mechanisms by which L. reuteri ZY15, isolated from healthy pig feces, mitigates intestinal barrier damage and inflammation caused by oxidative stress in Enterotoxigenic Escherichia coli (ETEC) K88-challenged mice. The results indicated that L. reuteri ZY15 increased antioxidant capacity by reducing serum reactive oxygen species (ROS) and superoxide dismutase (SOD) levels. L. reuteri ZY15 enhanced the intestinal barrier by upregulating mucin 1, mucin 2, occludin, zonula occludens-1 (ZO-1), and claudin-1 expressions in protein and mRNA levels. It significantly alleviated intestinal inflammation by reducing the proinflammatory cytokines interleukin-1β (IL-1β), interferon-γ (IFN-γ), tumor necrosis factor-α (TNF-α), and interleukin-17 (IL-17) mRNA and protein levels. Notably, L. reuteri ZY15 suppressed intestinal inflammation by inhibiting AKT/mTOR/HIF-1α/RORγt/IL-17 pathway activation. Additionally, it significantly altered the structure of gut microorganisms by enriching Akkermansia and Clostridia_UCG.014, and thereby re-establishing colonization resistance and alleviating ETEC K88-induced intestinal barrier damage and inflammation in mice. Taken together, our findings reveal the protective mechanism of L. reuteri ZY15 in mice challenged with ETEC K88 by regulating AKT/mTOR/HIF-1α/RORγt/IL-17 signaling and microbial imbalance. Leveraging these properties, live L. reuteri ZY15 offers a promising alternative treatment for Escherichia coli-induced diarrhea in weaned piglets.

Lactiplantibacillus plantarum is a widely studied probiotic species with significant strain-specific functional diversity, yet the molecular mechanisms underlying these variations remain largely unexplored. In this study, whole genome sequencing (WGS) and untargeted metabolomics were employed to comprehensively characterize the genetic architecture and extracellular metabolic profile of Lp. plantarum FRT4 (CGMCC 17955), a probiotic strain previously studied for its metabolic effects in animal models. WGS revealed a circular chromosome and five plasmids, encoding 3301 protein-coding genes enriched in amino acid biosynthesis, carbohydrate metabolism, and environmental response pathways. Carbohydrate-active enzymes (CAZy) annotation revealed 135 carbohydrate-active enzyme genes, dominated by glycoside hydrolases and glycosyl transferases. Untargeted metabolomic analysis comparing the fermentation supernatant of FRT4 with non-inoculated MRS medium revealed significant alterations in metabolite composition, including elevated levels of acetylcholine, nicotinamide adenine dinucleotide (NAD), and trans-3-coumarate, and reduced levels of uridine, inosine, and fructose-1-phosphate, indicating active modulation of neurotransmission, redox balance, and purine metabolism. KEGG (Kyoto Encyclopedia of Genes and Genomes) enrichment showed significant regulation of pathways related to amino acid metabolism, carbon metabolism, and cofactor biosynthesis. These findings highlight the metabolic versatility and functional potential of FRT4, offering mechanistic insights into its probiotic effects and providing a basis for its potential application in fermentation-based formulations.

The experiment aimed to optimize the fermentation parameters (nitrogen concentration and moisture concentration) of the citric acid residue produced by Aspergillus niger in a solid-state fermentation process. The experiment involved a seven-day double-factor solid-state fermentation of the fermentation substrate (a mixture of citric acid residue and wheat bran with a mass ratio of 4∶1) using Aspergillus niger. The urea addition amounts were 1%, 2%, and 3%, and the moisture concentrations were 40%, 50%, and 60%. The results showed that under the fermentation parameters of 50% moisture content and 3% urea content, the concentrations of crude fiber, neutral detergent fiber, and acid detergent fiber in the fermented citric acid residue were 15.36%, 36.99%, and 21.53% respectively, the reduced sugar concentration was 41.56 mg/g, the crude protein concentration was 24.78%, and the total energy was 168.92 MJ/kg. The study indicates that under the optimized fermentation conditions of the experiment, the fiber content of the citric acid residue fermented by Aspergillus niger was significantly reduced, the crude protein content was significantly increased, and it had the potential to become a high-quality protein feed raw material.

Obesity and type 2 diabetes mellitus are global health challenges often associated with disrupted lipid and amino acid metabolism, as well as gut microbiota dysbiosis. Probiotic interventions offer promising potential in ameliorating metabolic disorders, yet strain-specific mechanisms remain to be elucidated. In this study, a canine-derived Pediococcus acidilactici PA-1 was subjected to in vitro evaluation for probiotic properties, and its anti-obesity effects were investigated in high-fat diet (HFD)-induced obese mice. In vitro, PA-1 exhibited safety and favorable probiotic activity including gastrointestinal tolerance, adhesion potential, bile salt hydrolase activity, α-glucosidase inhibition and fatty acid absorption. In vivo, PA-1 supplementation significantly alleviated body weight gain, hepatic steatosis, and lipid accumulation in HFD-fed mice. Multi-omics analyses of liver revealed that PA‑1 modulated hepatic amino acid metabolism at the pathway level (e.g., alanine, aspartate and glutamate metabolism), and led to significant decreases in D‑serine, glycine, and L‑proline in the targeted panel, whereas several others (e.g., L‑aspartate, L‑alanine) showed trend-level decreases. PA‑1 concomitantly suppressed pyruvate flux into the TCA cycle and reduced several TCA intermediates (e.g., fumarate, malate, citrate), eventually Limiting acetyl-CoA availability for de novo Lipogenesis. Additionally, 16S rRNA sequencing demonstrated that PA-1 reshaped the gut microbiota by reducing the Firmicutes/Bacteroidota ratio and enriching the abundance of short-chain fatty acid-producing genera, leading to elevated SCFA concentrations in the cecal contents. This study suggests that PA-1 ameliorates HFD-induced obesity and metabolic disturbances by modulating hepatic amino acid metabolism and gut microbiota composition, highlighting its potential as a functional probiotic for managing obesity-related metabolic disorders.

Intestinal damage induced by immune stress leads to economic losses in broiler production; however, the underlying mechanisms remain unclear. This experiment investigated the effects of immune stress on the intestinal mucosa proteome of Arbour Acres (AA) broilers challenged with Escherichia coli lipopolysaccharide (LPS). A total of 144 one-day-old, male, AA broiler chickens were randomly divided into two groups: the treatment group was challenged with LPS and the control group received an equal volume of saline injection. On day 42, intestinal morphology, enterocytes and mucosal proteomes were analysed from three birds in each replicate, with a total of six replicates per group. The microvilli of intestinal epithelial cells exhibited damage and necrotic enterocytes were evident in broilers challenged with LPS. Proteomic analysis indicated that 851 proteins were differentially expressed in the intestinal mucosa of broiler chickens from the immune stress group; 463 proteins were down-regulated, and 388 proteins were up-regulated. Functional analysis revealed that LPS disrupted intestinal mucosa protein homeostasis, affecting beta-oxidation of fatty acids, oxidative stress and immune function. Furthermore, immune stress increased the expression of alanine, tyrosine, leucine, isoleucine, tryptophan, arginine and serine-tRNA ligase. The data suggest that gut damage in broiler chickens induced by LPS is triggered by dysfunctional and unbalanced proteostasis alterations. This study provides new insights into the mechanisms by which immune challenges impair nutrient absorption and mucosal immunity in broiler chickens.

Obesity and related metabolic disorders are major global health challenges. Postbiotics, such as heat-inactivated probiotics, have attracted attention for their improved safety, stability, and potential metabolic benefits compared to live probiotics. However, the comparative anti-obesity effects and mechanisms of live versus heat-inactivated Lactiplantibacillus plantarum FRT4 remain unclear, so this study systematically evaluated their effects and mechanisms in high-fat-diet-induced obese mice. Mice received oral administration of live or heat-inactivated FRT4 (prepared by heating in a water bath at 80 °C for 5 min) for 16 weeks. Comprehensive analyses included metabolic profiling, histological evaluation, serum and liver biomarkers, gut microbiota composition, liver metabolomics, and transcriptomics. Both live and inactivated FRT4 significantly reduced body weight gain, adiposity, hepatic steatosis, and dyslipidemia, with inactivated FRT4 exhibiting comparable or superior efficacy. Notably, inactivated FRT4 restored gut microbiota composition, increased short-chain fatty acid production, and regulated hepatic metabolic pathways. Multi-omics analyses revealed modulation of lipid biosynthesis, amino acid metabolism, and energy utilization pathways. Specifically, the “biosynthesis of unsaturated fatty acids” pathway was downregulated in metabolomics and significantly enriched in transcriptomics, highlighting its central role in FRT4M-mediated metabolic reprogramming. These findings demonstrate that heat-inactivated Lp. plantarum FRT4 exerts systemic anti-obesity effects via gut–liver axis modulation, supporting its potential as a promising postbiotic intervention for obesity and metabolic dysfunction.

Fatty liver hemorrhage syndrome (FLHS) has become one of the major factors leading to the death of laying hen in caged egg production. FLHS is commonly associated with lipid peroxidation, hepatocyte injury, decreased antioxidant capacity, and inflammation. However, there are limited evidences regarding the preventive effect of Lactiplantibacillus plantarum on FLHS in laying hens and its mechanisms. Our previous results showed that Lp. plantarum FRT4 alleviated FLHS by regulating lipid metabolism, but did not focus on its antioxidant and anti-inflammatory functions and mechanisms. Therefore, this study aimed to investigate the preventive mechanisms of Lp. plantarum FRT4 in alleviating FLHS, with a focus on its role in antioxidant activity and inflammation regulation. Supplementation with Lp. plantarum FRT4 enhanced the levels of T-AOC, T-SOD, and GSH-Px, while reducing the levels of TNF-α, IL-1β, IL-8, and NLRP3 in the liver and ovary of laying hens. Additionally, Lp. plantarum FRT4 upregulated the mRNA expressions of SOD1, SOD2, CAT, and GPX1, downregulated the mRNA expressions of pro-inflammatory factors IL-1β, IL-6, and NLRP3, and upregulated the mRNA expressions of anti-inflammatory factors IL-4 and IL-10. Lp. plantarum FRT4 improved the structure and metabolic functions of gut microbiota, and regulated the relative abundances of dominant phyla (Bacteroidetes, Firmicute, and Proteobacteria) and genera (Prevotella and Alistipes). Additionally, it influenced key KEGG pathways, including tryptophan metabolism, amino sugar and nucleotide sugar metabolism, insulin signaling pathway, FoxO signaling pathway. Spearman analysis revealed that the abundance of microbiota at different taxonomic levels was closely related to antioxidant enzymes and inflammatory factors. Furthermore, Lp. plantarum FRT4 modulated the mRNA expressions of related factors in the FoxO/TLR-4/NF-κB signaling pathway by regulating gut microbiota. Moreover, the levels of E2, FSH, and VTG were significantly increased in the ovary after Lp. plantarum FRT4 intervention. Lp. plantarum FRT4 effectively ameliorates FLHS in laying hens. This efficacy is attributed to its antioxidant and anti-inflammatory properties, which are mediated by modulating the structure and function of gut microbiota, and further intervening in the FoxO/TLR-4/NF-κB signaling pathway. These actions enhance hepatic and ovarian function and increase estrogen levels.

The white-rot fungus Irpex lacteus is recognized for its strong ligninolytic and polysaccharide-degrading capacity, but the key advantages in degrading lignocellulose and the regulation of its enzyme systems remain poorly understood. In this study, we identified a rich repertoire of carbohydrate-active enzymes in the genome of I. lacteus QJ. Relative to other white-rot fungi, an expanded glycoside hydrolase gene family in I. lacteus QJ suggesting strong potential for lignocellulose degradation. When I. lacteus QJ was cultivated on glucose or wheat straw for 4 and 8 days, wheat straw strongly induced carbohydrate-active enzyme genes on day 4, while ligninolytic enzyme genes exhibited delayed upregulation on day 8. The cellobiose dehydrogenase plays an important role in the degradation processes. Its expression pattern is consistent with that of cellulase, and it can support peroxidase activity by providing H2O2. These findings reveal temporal coordination between polysaccharide- and lignin-degrading enzymes, providing new theoretical ideas for the application of I. lacteus during the degradation process. Our results not only improve the mechanistic understanding of fungal lignocellulose deconstruction but also inform strategies to enhance biological pretreatment of agricultural residues for biorefinery applications.

Background/Objectives: Obesity is increasingly recognized as a global health concern due to its association with metabolic disorders and gut microbiota dysbiosis. While probiotics offer promise in regulating gut microbiota and improving host metabolism, strain-specific effects remain underexplored, particularly for canine-derived probiotics. This study aimed to isolate and characterize a novel probiotic strain, Ligilactobacillus animalis LA-1, and evaluate its anti-obesity effects and underlying mechanisms using a high-fat diet (HFD)-induced obese mouse model. Methods: LA-1 was isolated from the feces of a healthy dog and assessed for probiotic potential in vitro, including gastrointestinal tolerance, bile salt hydrolase activity, cholesterol-lowering capacity, and fatty acid absorption. Male C57BL/6J mice were fed either a standard chow diet or an HFD for 16 weeks, with HFD mice receiving oral LA-1 supplementation (2 × 109 CFU/day). Multi-omics analyses, including 16S rRNA gene sequencing, short-chain fatty acid (SCFA) quantification, and untargeted liver metabolomics, were employed to investigate the effects of LA-1 on gut microbiota composition, metabolic pathways, and obesity-related phenotypes. Results: LA-1 supplementation significantly alleviated HFD-induced weight gain, hepatic lipid accumulation, and adipose tissue hypertrophy, without affecting food intake. It improved serum lipid profiles, reduced liver injury markers, and partially restored gut microbiota composition, decreasing the Firmicutes/Bacteroidetes ratio and enriching SCFA-producing genera. Total SCFA levels, particularly acetate, propionate, and butyrate, increased following LA-1 treatment. Liver metabolomics revealed that LA-1 modulated pathways involved in lipid and amino acid metabolism, resulting in decreased levels of acetyl-CoA, triglycerides, and bile acids. Conclusions: L. animalis LA-1 exerts anti-obesity effects via gut microbiota modulation, enhanced SCFA production, and hepatic metabolic reprogramming. These findings highlight its potential as a targeted probiotic intervention for obesity and metabolic disorders.

This study explored Trichoderma asperellum’s lignocellulose degradation potential in wheat straw (WS) and NaOH-treated WS via solid-state fermentation (SSF) over 30 days. Compared to the control, WS treated with T. asperellum (TW) and NaOH-treated WS with T. asperellum (TN) showed increased dry matter loss rates of 15.67 and 15.76%, respectively. Cellulose degradation reached 33.51 and 28.00%, while hemicellulose degradation increased to 31.56 and 63.86%. Crude protein (CP) content rose to 10.96 and 7.44%, and reducing sugar content to 10.86 and 12.41 mg/g, respectively. T. asperellum effectively reduced lignocellulose content and enhanced substrate nutrition, supporting subsequent uses of WS as fertilizer, feed, or for bioethanol production. Enzymatic activity and structural analyses were performed to further confirm the lignocellulose-degrading ability of T. asperellum and to analyze the degradation mechanisms. Transcriptomic analysis revealed that, compared with the control group, the TN group had 4,548, 4,399, and 6,051 differentially expressed genes (DEGs) at 5, 10, and 30 days, respectively, mainly involved in cellulose and hemicellulose degradation, carbohydrate metabolism, carbohydrate transport, glycoside hydrolases, and polysaccharide binding. T. asperellum can modify lignin by expressing dye-decolorizing peroxidase genes, and multiple key genes were identified for further research into its genetic regulation in lignocellulose degradation.

This experiment aims to investigate the physicochemical properties of fermented soybean meal (FSBM) and its effects on the growth and development of broilers when used as a substitute for soybean meal (SBM). The process optimization of FSBM was based on indicators such as particle size, moisture content, temperature, and the amounts of protease and microbial agents added. The physicochemical indicators of the FSBM meal were measured accordingly. On this basis, 320 one-day-old AA broilers were randomly divided into 4 treatment groups, with each group having 8 replicates. The treatment groups were: control (CON) group was fed a basal diet. The experimental group replaced 5 % (FSBM-1), 7.5 % (FSBM-2), and 10 % (FSBM-3) of SBM with FSBM. The trial period lasted for 42 d. The results indicate that the crude protein (CP) and acid-soluble protein (ASP) content of FSBM have significantly increased. Additionally, the amino acid content of FSBM surpasses that of SBM. Furthermore, the peak area percentage (PAP), number average molecular weight (NAMW), and weight average molecular weight (WAMW) for molecules below 5000 Da have shown significant increases (P<0.05). FSBM also significantly reduces anti-nutritional factors, including raffinose, stachyose, glycinin, etc. In the broiler chicken experiment, the ADG of the FSBM-1 group from 22 to 42 d and from 1 to 42 d was significantly increased (P<0.05), while the F/G was significantly reduced (P<0.05). Additionally, compared to the CON group, the nutrient apparent metabolism rates of dry matter (DM), crude protein (CP), and energy (EN) in the diet were also significantly enhanced (P<0.05). The comparison of broiler chickens in the FSBM-1 group at 21 d and 42 d shows a significant decrease (P<0.05) in the crypt depth (CD), while the villus height to crypt depth (V/C) significantly increased (P<0.05). In summary, fermentation can significantly reduce the anti-nutritional factors present in SBM and enhance feed quality. Replacing 5% of SBM with FSBM can notably improve the growth performance and intestinal morphology of broiler chickens.

Large amounts of spent mushroom substrate (SMS) are produced globally, but their utilization efficiency is low, which leads to negative environmental impacts, such as water, soil, and air pollution. SMS contains nutrients, such as cell proteins, with a potential application in animal feed. However, the lignocellulose in SMS restricts animal digestion and absorption, thus hindering its application in animal nutrition. We investigated the potential of cellulase, xylanase, β-galactosidase, and a variety of microorganisms to optimize the conditions for reducing sugars’ (RS) production and the degradation rate of neutral detergent fibers. The results showed that the optimum proportion of multiple enzymes for glucose production of up to 210.89 mg/g were 10% cellulase, 10% xylanase, and 2% β -galactosidase, at 50 °C and 60% moisture for a 20 h hydrolysis duration. To enhance the optimal enzymolysis combination, co-fermentation experiments with multiple microorganisms and enzymes showed that inoculation with 10% Bacillus subtilis, 2% Pediococcus acidilactici, and 2% Saccharomyces cerevisiae, in combination with 10% cellulase, 10% xylanase, 2% β-galactosidase, and 1% urea, at 36.8°C and 59% moisture for 70 h hydrolysis, could lead to a 23.69% degradation rate of the neutral detergent fiber. This process significantly increased the degradation rate of the neutral detergent fiber and the nutrient content of Pleurotus eryngii compared to the initial fermentation conditions. Overall, our study generated optimal co-fermentation conditions for bacteria and enzymes and provides a practical reference for biological feed synthesis using P. eryngii spent mushroom substrate.

The natural edible characteristics of Chinese herbs have led more and more people to study them as an alternative product to antibiotics. In this study, crude extracts of Glycyrrhiza radix and Atractylodes macrocephala (abbreviated as GRAM) with glycyrrhizic acid content not less than 0.2 mg/g were selected to evaluate the effects of GRAM on the immune and antioxidant capacity of model animals. Thirty 21-day-old male Leghorn chickens were weighed and randomly assigned to one of three groups of ten animals each. The treatments comprised a control group (CON), in which saline was injected at day 31, day 33, and day 35, an LPS-treated group (LPS), in which LPS (0.5 mg/kg of BW) was injected at day 31, day 33, and day 35, and finally a GRAM and LPS-treated group, (G-L) in which a GRAM-treated diet (at GRAM 2 g/kg) was fed from day 21 to day 35 with LPS injection (0.5 mg/kg of BW) at day 31, day 33, and day 35. The results of diarrhea grade and serum antioxidant measurement showed that the LPS group had obvious diarrhea symptoms, serum ROS and MDA were significantly increased, and T-AOC was significantly decreased. The oxidative stress model of LPS was successfully established. The results of immune and antioxidant indexes showed that feeding GRAM significantly decreased levels of the pro-inflammatory factors TNF-α, IL-1β, and IL-6 (p < 0.05) and significantly increased levels of the anti-inflammatory factors IL-4 and IL-10 and levels of the antioxidant enzymes GSH-Px and CAT (p < 0.05). GRAM resisted the influence of LPS on ileum morphology, liver, and immune organs and maintained normal index values for ileum morphology, liver, and immune organs. In summary, this study confirmed the antidiarrheal effect of GRAM, which improved the immune and antioxidant capacity of model animals by regulating inflammatory cytokine levels and antioxidant enzyme activity in poultry.

This research sought to assess the anti-obesity potential of Enterococcus faecalis EF-1. An extensive and robust in vitro methodology confirmed EF-1’s significant potential in combating obesity, probably due to its excellent gastrointestinal tract adaptability, cholesterol-lowering property, bile salt hydrolase activity, α-glucosidase inhibition, and fatty acid absorption ability. Moreover, EF-1 exhibited antimicrobial activity against several pathogenic strains, lacked hemolytic activity, and was sensitive to all antibiotics tested. To further investigate EF-1’s anti-obesity properties in vivo, a high-fat diet (HFD) was used to induce obesity in C57BL/6J mice. Treatment with EF-1 (2 × 109 CFU/day) mitigated HFD-induced body weight gain, reduced adipose tissue weight, and preserved liver function. EF-1 also ameliorated obesity-associated microbiota imbalances, such as decreasing the Firmicutes/Bacteroidetes ratio and boosting the levels of bacteria (Faecalibacterium, Mucispirillum, Desulfovibrio, Bacteroides, and Lachnospiraceae_NK4A136_group), which are responsible for the generation of short-chain fatty acids (SCFAs). Concurrently, the levels of total SCFAs were elevated. Thus, following comprehensive safety and efficacy assessments in vitro and in vivo, our results demonstrate that E. faecalis EF-1 inhibits HFD-induced obesity through the regulation of gut microbiota and enhancing SCFA production. This strain appears to be a highly promising candidate for anti-obesity therapeutics or functional foods.

Background Fatty liver hemorrhage syndrome (FLHS) becomes one of the most major factors resulting in the laying hen death for caged egg production. This study aimed to investigate the therapeutic effects of Lactiplantibacillus plantarum ( Lp. plantarum ) FRT4 on FLHS model in laying hen with a focus on liver lipid metabolism, and gut microbiota. Results The FLHS model of laying hens was established by feeding a high-energy low-protein (HELP) diet, and the treatment groups were fed a HELP diet supplemented with differential proportions of Lp. plantarum FRT4. The results indicated that Lp. plantarum FRT4 increased laying rate, and reduced the liver lipid accumulation by regulating lipid metabolism (lipid synthesis and transport) and improving the gut microbiota composition. Moreover, Lp. plantarum FRT4 regulated the liver glycerophospholipid metabolism. Meanwhile, “gut-liver” axis analysis showed that there was a correlation between gut microbiota and lipid metabolites. Conclusions The results indicated that Lp. plantarum FRT4 improved the laying performance and alleviated FLHS in HELP diet-induced laying hens through regulating “gut-liver” axis. Our findings reveal that glycerophospholipid metabolism could be the underlying mechanism for the anti-FLHS effect of Lp. plantarum FRT4 and for future use of Lp. plantarum FRT4 as an excellent additive for the prevention and mitigation of FLHS in laying hens.

Bacillus licheniformis (B. Licheniformis) has been considered to be an effective probiotic to maintain gut health and boost productivity in the pig industry, but there is no complete understanding of its mechanisms. We determined whether weaned piglets exposed to BL-S6 (probiotic) had altered intestinal barrier function or microbiota composition. In our study, 108 weaned piglets (54 barrows and 54 gilts) were divided equally into three groups, each with six pens and six piglets/pen, and fed a basal diet supplemented without or with antibiotic (40 g/t of Virginiamycin and 500 g/t of Chlortetracycline) or probiotic (1000 g/t of B. Licheniformis) for a 14-day trial. On day 14, one piglet was chosen from each pen to collect blood and intestinal samples. Compared with the control group, dietary supplementation with a probiotic promoted body weight (BW) gain and average daily gains (ADG) while reducing diarrhea incidence (p < 0.05). Probiotics enhanced superoxidase dismutase (SOD) activity and decreased malondialdehyde (MDA) levels in serum (p < 0.05), and increased the level of mRNA expression of SOD1, Nrf2, and HO-1 (p < 0.05) in the jejunum mucosa. Moreover, supplementation with probiotics improved intestinal mucosal integrity as evidenced by higher villus heights and a higher ratio of villus heights to crypt depths (duodenum and jejunum) and higher mRNA and protein levels of occludin and ZO-1 in jejunum mucosa (p < 0.05). The intestinal sIgA levels (p < 0.05) were elevated in the probiotic group, and that of serum immunoglobulin A (IgA) tended to be higher (p = 0.09). Furthermore, weaning piglets who were given probiotics had a better balance of the cecum microbiota, with lactobacillus abundance increased and clostridium_sensu_stricto_1 abundance decreased. In conclusion, dietary supplementation with the probiotic BL-S6 promoted intestinal integrity, which was associated, in part, with modulating intestinal barrier function and microbial diversity in weaned piglets; it may offer a promising alternative to antibiotics to prevent diarrhea.