Sashuang Dong

This study systematically evaluated the stability, bioaccessibility, and gut microecological regulatory potential of lightly fermented sour tea (ST) polyphenols during in vitro simulated digestion. While ST maintained stability in the gastric phase, colonic fermentation significantly reduced α-glucosidase inhibition by over 70% and decreased antioxidant capacities. However, ST exhibited powerful prebiotic effects by modulating gut microbiota in a concentration-dependent manner. The 1.0 mg/mL treatment yielded the most favorable outcomes, possessing the highest number of unique OTUs and optimal community diversity. Notably, this concentration significantly reduced the Firmicutes/Bacteroidota ratio and enriched beneficial SCFA-producers: Bacteroides abundance surged from 0.34% in the control to 12.42%, while Phascolarctobacterium increased from 0.15% to 3.72%. Furthermore, functional prediction indicated a specific upregulation in carbohydrate degradation and secondary metabolite biosynthesis pathways. These findings suggested that ST exhibits excellent stability and functional activity during digestion and holds promise as a natural dietary intervention for enhancing gut microecology and promoting host health.

The dynamic regulatory mechanisms by which Lactobacillus casei 139 fermentation modulates the nutritional components and flavor characteristics of Aronia melanocarpa (Michx) Elliott juice were investigated through a systematic evaluation of temporal changes in nutritional and flavor profiles during fermentation. The results indicated that the viable cell density peaked at 6.01 log CFU/mL within 24 h. During fermentation, the pH of A. melanocarpa juice initially increased slightly within 48 h before gradually decreasing, while titratable acidity consistently decreased, reflecting the metabolic activity of Lactobacillus casei 139. Concurrently, total sugar content exhibited a decline followed by a leveling off to a steady state. It was found that the contents of total phenolic and flavonoid contents decreased initially, while the color difference a* first decreased, then increased. Combined electronic nose and sensory analyses revealed that fermentation enhanced aroma complexity, and mitigated astringency by promoting aromatic compound accumulation. The research confirms that fermentation with strain L. casei 139 can effectively improve both the sensory quality and nutritional value of fermented A. melanocarpa beverages.

Type 2 diabetes (T2D) is a complex metabolic disease characterized by chronic hyperglycemia due to insulin resistance and inadequate insulin secretion. Beyond the classically implicated organs, emerging evidence highlights the gut as a central player in T2D pathophysiology through its interactions with metabolic organs. The gut hosts trillions of microbes and enteroendocrine cells that influence inflammation, energy homeostasis, and hormone regulation. Disruptions in gut homeostasis (dysbiosis and increased permeability) have been linked to obesity, insulin resistance, and β-cell dysfunction, suggesting multifaceted “Gut-X axes” contribute to T2D development. We aimed to comprehensively review the evidence for gut-mediated crosstalk with the pancreas, endocrine system, liver, and kidneys in T2D. Key molecular mechanisms (incretins, bile acids, short-chain fatty acids, endotoxins, etc.) were examined to construct an integrated model of how gut-derived signals modulate metabolic and inflammatory pathways across organs. We also discuss clinical implications of targeting Gut-X axes and identify knowledge gaps and future research directions. A literature search (2015–2025) was conducted in PubMed, Scopus, and Web of Science, following PRISMA guidelines (Preferred Reporting Items for Systematic Reviews). Over 150 high-impact publications (original research and review articles from Nature, Cell, Gut, Diabetologia, Lancet Diabetes & Endocrinology, etc.) were screened. Data on gut microbiota, enteroendocrine hormones, inflammatory mediators, and organ-specific outcomes in T2D were extracted. The GRADE framework was used informally to prioritize high-quality evidence (e.g., human trials and meta-analyses) in formulating conclusions. T2D involves perturbations in multiple Gut-X axes. This review first outlines gut homeostasis and T2D pathogenesis, then dissects each axis: (1) Gut–Pancreas Axis: how incretin hormones (GLP-1 and GIP) and microbial metabolites affect insulin/glucagon secretion and β-cell health; (2) Gut–Endocrine Axis: enteroendocrine signals (e.g., PYY and ghrelin) and neural pathways that link the gut with appetite regulation, adipose tissue, and systemic metabolism; (3) Gut–Liver Axis: the role of microbiota-modified bile acids (FXR/TGR5 pathways) and bacterial endotoxins in non-alcoholic fatty liver disease (NAFLD) and hepatic insulin resistance; (4) Gut–Kidney Axis: how gut-derived toxins and nutrient handling intersect with diabetic kidney disease and how incretin-based and SGLT2 inhibitor therapies leverage gut–kidney communication. Shared mechanisms (microbial SCFAs improving insulin sensitivity, LPS driving inflammation via TLR4, and aryl hydrocarbon receptor ligands modulating immunity) are synthesized into a unified model. An integrated understanding of Gut-X axes reveals new opportunities for treating and preventing T2D. Modulating the gut microbiome and its metabolites (through diet, pharmaceuticals, or microbiota therapies) can improve glycemic control and ameliorate complications by simultaneously influencing pancreatic islet function, hepatic metabolism, and systemic inflammation. However, translating these insights into clinical practice requires addressing gaps with robust human studies. This review provides a state-of-the-art synthesis for researchers and clinicians, underlining the gut as a nexus for multi-organ metabolic regulation in T2D and a fertile target for next-generation therapies.

Background: Probiotics have recently emerged as promising agents in the prevention and treatment of various human diseases. This study investigates the therapeutic potential of Weizmannia coagulans SA9 in the management of type 2 diabetes mellitus (T2DM). Methods: The in vitro antidiabetic activity of W. coagulans SA9 was primarily assessed via its α-glucosidase inhibitory capacity, complemented by metabolomic profiling to identify putative bioactive metabolites. The antidiabetic efficacy was further evaluated in a db/db mouse model, focusing on glucose tolerance, inflammatory biomarkers, and gut microbiota composition. Results: W. coagulans SA9 showed significant inhibitory effects on α-glucosidase and α-amylase, and DNJ and other active substances were detected in its culture supernatant. After 6 weeks of continuous administration, the fasting blood glucose level, glucose tolerance, and inflammation indexes of mice were significantly improved. Beneficial changes in the structure of the intestinal flora occurred after the probiotic intervention, as evidenced by a significant decrease in harmful bacteria (e.g., Aerococcus urinaeequi) and a significant enrichment of beneficial bacteria (e.g., Limosilactobacillus reuteri). Conclusions: W. coagulans SA9 exerts robust antidiabetic effects and holds promise as a novel strategy for the prevention and management of T2DM.

A strain identified as Schleiferilactobacillus harbinensis was isolated from Chinese sauerkraut, and its exopolysaccharide (EPS) exhibited excellent in vitro cholesterol-lowering bioactivity. Besides, the whole genome of this strain and the structure characteristics of the purified EPS were investigated in this study. S. harbinensis Z171 presented a strong EPS production capacity, with five nucleotide sugar biosynthesis pathways regulated by an EPS synthesis gene cluster. Structural characterization revealed that the purified fraction F-EPS1A was a neutral polysaccharide with a molecular weight of 6.4 × 10⁴ Da. The structure of F-EPS1A contained a backbone that comprised blocks of four 1,2-linked and three 1,3-linked alpha mannose units. Some 1,2-linked alpha mannose residues were branched at C6 with side chains formed by single alpha mannose or a disaccharide consisting of 1,6-linked alpha mannose residues. The structural characteristics endowed F-EPS1A with a high level of cholesterol-lowering bioactivity. In addition, whole genome analysis indicated that S. harbinensis Z171 possessed a strong EPS production capacity. These findings suggested that the EPS produced by S. harbinensis Z171 could be applied as a potential cholesterol-lowering prebiotic agent or supplement in functional food.

Aronia melanocarpa is a fruit rich in antioxidant compounds with notable health benefits; however, its astringency limits its widespread consumption. This study examined the effects of fermentation with Lactiplantibacillus plantarum 1243 and Lacticaseibacillus paracasei 139 on the microbiological dynamics, quality indicators, and flavor profile of Aronia melanocarpa juice. The results showed that, compared to the unfermented juice, the microbial count reached 7.03 lg CFU/mL at 24 h of fermentation, followed by a decline to 3.90 lg CFU/mL at 96 h. Soluble sugars experienced an initial decline, subsequently increased, and then decreased again. Acidity firstly reduced and then increased, while pH increased initially and then decreased. Total phenolic and flavonoid contents remained relatively stable at 24 h before showing a significant reduction. The DPPH radical scavenging activity significantly increased during fermentation, reaching a peak of 71.7% at 48 h. Overall improvement was observed in color and sensory acceptance of the juice. Flavor analysis demonstrated an increase in aromatic organic compounds, aliphatic aromatics, and methyl compounds, contributing to aroma enhancement in Aronia melanocarpa juice. These findings establish a basis for the use of lactic acid bacteria fermentation to enhance the quality, flavor, and functionality of Aronia melanocarpa juice, supporting the development of functional beverages.