This study utilized a proprietary dynamic biomimetic digestion reactor to compare the differential behaviors of broken-wall pine pollen (PB), whole-wall pine pollen (WPB), and pine pollen wall extract (T) during simulated gastrointestinal digestion and colonic fermentation in middle-aged individuals. Morphological changes were observed using scanning electron microscopy, and glucose release, enzyme activity, intestinal gas composition, and gut microbiota structure were dynamically monitored. The results indicate that cell wall disruption significantly accelerated structural breakdown, resulting in the highest glucose release, superoxide dismutase, and lipase activities during the gastric and small intestinal phases, as well as the highest activity of alkaline phosphatase and H₂ and CO₂ gases during colonic fermentation. Due to its intact outer wall, WPB exhibited more robust and sustained enzyme activity and gas production, which was particularly beneficial for maintaining catalase activity in the descending colon of women. The T group demonstrated exceptional glucose and flavonoid release during digestion, but exhibited low SOD activity in the colon and a specific increase in H₂S and VOCs in the descending colon. Furthermore, all three groups inhibited Escherichia-Shigella, with gender differences observed in the regulatory patterns. This study elucidates the processing-driven differential regulatory characteristics of pine pollen on in vitro intestinal fermentation behaviors, providing an in vitro experimental basis for the development of differentiated pine pollen products tailored to the needs of different populations.

Akkermansia muciniphila, a next-generation probiotic in the human intestinal mucus layer, exhibits significant health-promoting properties. However, traditional static culture systems fail to replicate the dynamic peristaltic environment of the gastrointestinal tract, limiting understanding of its metabolic characteristics. This study employed an improved gastrointestinal bioreactor simulating intestinal peristalsis to investigate A. muciniphila growth dynamics and metabolomic profiles under dynamic conditions. Dynamic cultivation significantly enhanced bacterial growth. Biomass reached 1.32 ± 0.03 g/L in bovine heart infusion (BHI) medium and 2.03 ± 0.05 g/L in BHI supplemented with 2.5 g/L porcine mucin. These values represent increases of 45.05% and 123.08% relative to static BHI cultures, respectively. Dynamic conditions markedly elevated short-chain fatty acid production (acetic, propionic, isobutyric, isovaleric acids). Untargeted metabolomics identified 1463 metabolites with 1294 showing significant differential expression. Dynamic cultivation substantially altered amino acid biosynthesis, fatty acid, purine, and pyrimidine metabolism. These findings advance the understanding of A. muciniphila physiology and provide insights into its metabolic characteristics under simulated intestinal conditions.