Dietary Supplementation of Brevibacillus laterosporus S62-9 Improves Broiler Growth and Immunity by Regulating Cecal Microbiota and Metabolites.

Brevibacillus laterosporus has been added as a direct-fed microbiota to chicken. Yet, few studies have reported the effects of B. laterosporus on broiler growth and gut microbiota. The aim of this study was to evaluate the effects of B. laterosporus S62-9 on growth performance, immunity, cecal microbiota, and metabolites in broilers. A total of 160 1-day-old broilers were randomly divided into S62-9 and control groups, with or without 106 CFU/g B. laterosporus S62-9 supplementation, respectively. During the 42 days feeding, body weight and feed intake were recorded weekly. Serum was collected for immunoglobulin determination, and cecal contents were taken for 16S rDNA analysis and metabolome at Day 42. Results indicated that the broilers in S62-9 group showed an increase in body weight of 7.2% and 5.19% improvement in feed conversion ratio compared to the control group. The B. laterosporus S62-9 supplementation promoted the maturation of immune organs and increased the concentration of serum immunoglobulins. Furthermore, the α-diversity of cecal microbiota was improved in the S62-9 group. B. laterosporus S62-9 supplementation increased the relative abundance of beneficial bacteria including Akkermansia, Bifidobacterium, and Lactobacillus, while decreased the relative abundance of pathogens including Klebsiella and Pseudomonas. Untargeted metabolomics revealed that 53 differential metabolites between the two groups. The differential metabolites were enriched in 4 amino acid metabolic pathways, including arginine biosynthesis and glutathione metabolism. In summary, B. laterosporus S62-9 supplementation could improve the growth performance and immunity through the regulation of gut microbiota and metabolome in broilers.

Dietary Effect of Brevibacillus laterosporus S62-9 on Chicken Meat Quality, Amino Acid Profile, and Volatile Compounds.

Probiotics are being used in diets to improve the quality of chicken meat. The aim of the study was to investigate the effects of dietary supplementation with Brevibacillus laterosporus S62-9 microbial agent on the meat quality, amino acids, and volatile compounds of chicken. The experiment was carried out with 160 1-day-old Arbor Acres male broiler chickens, rearing for 42 d. The chickens were randomly divided into two groups of 8 replicates each, with 10 chickens in each group. No supplement was added to the basal diet in the control group and Brevibacillus laterosporus S62-9 microbial agent was added to the diet of the experimental group. At the end of the experiment, the meat quality, meat chemical composition, amino acid composition, and volatile compounds of chicken were determined. The results showed that pH (p < 0.05), pressing loss (p < 0.05), cooking loss (p < 0.05), and shear force (p < 0.01) were notably decreased, the percentage of breast meat (p < 0.01), protein content (p < 0.05) were visibly increased, and remarkable changes were observed in the amino acid composition (change in seven amino acids) and volatile compounds profile (an increase of about 20-fold in the contents of 1-octen-3-ol and hexanal). In summary, it was found that Brevibacillus laterosporus S62-9 microbial agent can be used as a novel and effective feed supplement to improve the nutritional quality and flavor characteristics of broilers.

Anti-inflammatory and gut microbiota regulatory effects of walnut protein derived peptide LPF in vivo.

Walnut peptides have been reported to exhibit diverse activities. In this study, we investigated the protective and recovery effects of the walnut derived peptide leucine-proline-phenylalanine (LPF) on dextran sulfate sodium (DSS)-induced colitis in mice. The peptide LPF mitigated the severity of symptoms during the development phase of colitis, as evidenced by changes in body weight, disease activity index score, and serum inflammatory cytokine levels. Moreover, the treatment groups showed beneficial effects, including increased colon length, reduced colonic cell apoptosis, decreased production of inflammatory factors, and expansion of splenic regulatory T cells during the recovery period. Additionally, 16S rDNA sequencing results indicated that 100 mg/kg LPF (M group) reversed the dysbiosis of gut microbiota in colitis mice. This included partial recovery of diversity of microbiota, increase in relative abundance of the family Lachnospiraceae and Ruminococcaceae during the development phase of colitis. Additionally, the composition of gut microbiota in the M group was constantly improved during the recovery period of colitis, showing increased relative abundance of beneficial genera and decreased abundance of potentially harmful genera compared with that in the DSS group. In summary, the peptide LPF could contribute to remission of colitis symptoms and restoration through reduction in cell apoptosis, anti-inflammatory effects, and regulation of gut microbiota.