Effect of α-linolenic acid (ALA) on proliferation of probiotics and its adhesion to colonic epithelial cells

Functional and mechanistic studies of a phytogenic formulation, Shrimp Best, in growth performance and vibriosis in whiteleg shrimp

Climate change and disease threaten shrimp farming. Here, we studied the beneficial properties of a phytogenic formulation, Shrimp Best (SB), in whiteleg shrimp. Functional studies showed that SB dose-dependently increased shrimp body weight and decreased feed conversion ratio. We found that SB protected against Vibrio parahaemolyticus as evidenced by survival rate, bacterial load, and hepatopancreatic pathology in shrimp. Finally, we explored the likely mechanism by which SB affects growth performance and vibriosis in shrimp. The 16S rRNA sequencing data showed that SB increased 6 probiotic genera and decreased 6 genera of pathogenic bacteria in shrimp. Among these, SB increased the proportion of Lactobacillus johnsonii and decreased that of V. parahaemolyticus in shrimp guts. To dissect the relationship among SB, Lactobacillus and Vibrio, we investigated the in vitro regulation of Lactobacillus and Vibrio by SB. SB at ≥ 0.25 μg/mL promoted L. johnsonii growth. Additionally, L. johnsonii and its supernatant could inhibit V. parahaemolyticus. Furthermore, SB could up-regulate five anti-Vibrio metabolites of L. johnsonii, which caused bacterial membrane destruction. In parallel, we identified 3 fatty acids as active compounds from SB. Overall, this work demonstrated that SB improved growth performance and vibriosis protection in shrimp via the regulation of gut microbiota.

Effects of postbiotics on chronic diarrhea in young adults: a randomized, double-blind, placebo-controlled crossover trial assessing clinical symptoms, gut microbiota, and metabolite profiles

Chronic diarrhea has a considerable impact on quality of life. This randomized, double-blind, placebo-controlled crossover intervention trial was conducted with 69 participants (36 in Group A, 33 in Group B), aiming to investigate the potential of postbiotics in alleviating diarrhea-associated symptoms. Participants received postbiotic Probio-Eco® and placebo for 21 days each in alternating order, with a 14-day washout period between interventions. The results showed that postbiotic intake resulted in significant improvements in Bristol stool scale score, defecation frequency, urgency, and anxiety. Moreover, the postbiotic intervention increased beneficial intestinal bacteria, including Dysosmobacter welbionis and Faecalibacterium prausnitzii, while reducing potential pathogens like Megamonas funiformis. The levels of gut Microviridae notably increased. Non-targeted metabolomics analysis revealed postbiotic-driven enrichment of beneficial metabolites, including α-linolenic acid and p-methoxycinnamic acid, and reduction of diarrhea-associated metabolites, including theophylline, piperine, capsaicin, and phenylalanine. Targeted metabolomics confirmed a significant increase in fecal butyric acid after postbiotic intervention. The levels of aromatic amino acids, phenylalanine and tryptophan, and their related metabolites, 5-hydroxytryptophan and kynurenine, decreased after the postbiotic intervention, suggesting diarrhea alleviation was through modulating the tryptophan-5-hydroxytryptamine and tryptophan-kynurenine pathways. Additionally, chenodeoxycholic acid, a diarrhea-linked primary bile acid, decreased substantially. In conclusion, postbiotics have shown promise in relieving chronic diarrhea.

Lactobacillus co-fermentation of Cerasus humilis juice alters chemical properties, enhances antioxidant activity, and improves gut microbiota

Fermentation with Lactobacillus has been shown to improve the nutritional value of juice. In this study, Cerasus humilis juice was fermented using two commercial probiotics, namely, Lactobacillus acidophilus and Lactobacillus plantarum. The total antioxidant capacity (TAOC), viable count, chemical properties, antioxidant activity after in vitro digestion, and alterations in the gut microbiota composition of the fermented juice were investigated. After fermentation, the TAOC increased from 107.66 U mL-1 to 126.72 U mL-1; viable count increased from 5.85 lg (CFU mL-1) to 8.17 lg (CFU mL-1); and the contents of total phenols, total flavonoids, proanthocyanins, four organic acids, and 29 amino acids had changed. Overall, 47 compounds were identified in the juice, 20 of which were enriched after fermentation. Furthermore, Lactobacillus co-fermentation improved the antioxidant properties of the juice after in vitro digestion and increased the abundance of probiotics to regulate the gut microbiota. These findings illustrate the potential use of Lactobacillus acidophilus and Lactobacillus plantarum in the co-fermentation of C. humilis juice to enhance its nutritional and functional properties.

Kidney tea ameliorates hyperuricemia in mice via altering gut microbiota and restoring metabolic profile

Clerodendranthus spicatus (Thunb.) C. Y. Wu, also known as kidney tea (KT), has been widely employed in kidney protection in Chinese Medicine. It has been reported that KT can lower uric acid (UA) and mitigate gout, while the mechanism remains to be elucidated. Given the close relationship between hyperuricemia (HUA), intestinal flora and host metabolism, this study aimed to explore the mechanism by which KT lowers UA from the perspective of the fecal microbiome and metabolome. Initially, mice were intraperitoneally injected with potassium oxonate to induce the HUA model. The results showed that KT markedly reduced the serum level of UA and impaired renal damage in HUA mice. Subsequently, the result of 16S rRNA gene sequencing analysis indicated that KT administration appeared a significant improvement in the structure of the intestinal flora, especially increased the abundances of Roseburia and Enterorhabdus, while decreased the abundances of Ileibacterium and UBA1819. Moreover, the levels of differential metabolites (including twenty-five in feces and eight in serum) identified by untargeted metabolomics returned to normal after KT intervention. Taken together, the mechanism of KT in alleviating HUA is related to the regulation of the intestinal flora and the remodeling of metabolic disorders, which will lay a theoretical foundation for KT as a UA-lowering drug.

Effect of Complex Prebiotics on the Intestinal Colonization Ability of Limosilactobacillus fermentum DALI02

Intestinal colonization is beneficial to the role of probiotics, and prebiotics can promote the adhesion and colonization of probiotics in the intestine. This study optimized the combination of complex prebiotics that could improve the growth ability and adhesion ability of Limosilactobacillus fermentum (L. fermentum) DALI02 to Caco-2 cells in vitro and determined the effect of its colonization quantity and colonization time in the immunocompromised rat model. The results showed that all five prebiotics (fructo-oligosaccharides (FOS), galacto-oligosaccharides (GOS), inulin, stachyose, and xylo-oligosaccharides (XOS)) significantly promoted the growth and adhesion of L. fermentum DALI02. It was found that 0.5% (w/w) inulin had the best growth promotion effect, and 0.5% FOS had the strongest adhesion promotion (the adhesion rate was increase by 1.75 times). In addition, 0.05% FOS, 0.20% GOS, 0.30% inulin, 0.20% stachyose, and 0.30% XOS could significantly improve the adhesion rate of L. fermentum DALI02 from 1.72% to 3.98%. After 1 w of intervention, the quantity of colonization in the fermented broth with prebiotics group was significantly higher than that in the fermented broth group. The intervention time was extended from 1 d to 4 w, and the amount of colonization of L. fermentum DALI02 in the fermented broth with prebiotics group increased significantly from 4.32 lgcopies/g to 5.12 lgcopies/g. After the intervention, the serum levels of lipopolysaccharide (LPS) and D-lactic acid in rats were significantly reduced, and the most significant was in the fermented broth with prebiotics group, with LPS and D-lactic acid levels of 74.11 pg/mL and 40.33 μmol/L, respectively. Complex prebiotics can promote the growth and adhesion of L. fermentum DALI02 and significantly increase the quantity of colonization and residence time of the strain in the intestine, which helps the restoration of intestinal barrier function and other probiotic effects.

Targeting intestinal flora and its metabolism to explore the laxative effects of rhubarb

Rhubarb, a traditional herb, has been used in clinical practice for hundreds of years to cure constipation, but its mechanism is still not clear enough. Currently, growing evidence suggests that intestinal flora might be a potential target for the treatment of constipation. Thus, the aim of this study was to clarify the laxative effect of rhubarb via systematically analyzing the metagenome and metabolome of the gut microbiota. In this study, the laxative effects of rhubarb were investigated by loperamide-induced constipation in rats. The gut microbiota was determined by high-throughput sequencing of 16S rRNA gene. Ultra-high performance liquid chromatography-quadrupole time-of-flight mass spectrometry was used for fecal metabolomics analysis. The data showed that rhubarb could significantly shorten gastrointestinal transit time, increase fecal water content and defecation frequency, improve gastrointestinal hormone disruption, and protect the colon mucus layer. Analysis of 16S rRNA gene sequencing indicated that rhubarb could improve the disorder of intestinal microbiota in constipated rats. For example, beneficial bacteria such as Ligilactobacillus, Limosilalactobacillus, and Prevotellaceae UCG-001 were remarkably increased, and pathogens such as Escherichia-Shigella were significantly decreased after rhubarb treatment. Additionally, the fecal metabolic profiles of constipated rats were improved by rhubarb. After rhubarb treatment, metabolites such as chenodeoxycholic acid, cholic acid, prostaglandin F2α, and α-linolenic acid were markedly increased in constipation rats; in contrast, the metabolites such as lithocholic acid, calcidiol, and 10-hydroxystearic acid were notably reduced in constipation rats. Moreover, correlation analysis indicated a close relationship between intestinal flora, fecal metabolites, and biochemical indices associated with constipation. In conclusion, the amelioration of rhubarb in constipation might modulate the intestinal microflora and its metabolism. Moreover, the application of fecal metabolomics could provide a new strategy to uncover the mechanism of herbal medicines.Key points• Rhubarb could significantly improve gut microbiota disorder in constipation rats.• Rhubarb could markedly modulate the fecal metabolite profile of constipated rats.