Exploring the relationship between polysaccharide compositional features and physiological functions: Insights from Rosa roxburghii and Brasenia schreberi

Background The relationship between structural variations of polysaccharides and their physiological roles remains unclear. Monosaccharide composition influences their antioxidant activity, potentially linking to blood glucose regulation and microbiome modulation. Methods This study focused on Rosa roxburghii Tratt polysaccharide (RP) and Brasenia schreberi polysaccharide (BP). Fractions BSP-40, BSP-60, RRTP-40, and RRTP-60 were prepared, and their structure-function relationships were analyzed via in vitro assays and animal intervention experiments. Results RRTP-40/60 were rich in galacturonic acid and glucose, while BSP-40/60 mainly contained glucose and mannose. RRTP-60 and BSP-40 exhibited a Congo red binding pattern characteristic of a triple helix, unlike RRTP-40 and BSP-60. Polysaccharide administration reduced fasting blood glucose by 24.44% (RP group), 27.56% (RP-BP group), and 29.65% (BP group), decreased triglyceride (TG) and malondialdehyde (MDA) levels, improved hepatic cell morphology, and reduced inflammatory markers. Specifically, the abundance of Muribaculaceae has significantly increased. This bacterial family has been reported to exhibit increased abundance in health interventions and is believed to exert a positive influence on host metabolism through pathways such as the production of short-chain fatty acids, while harmful Lachnospiraceae decreased. Monosaccharide composition correlated significantly with intestinal microbiota. Conclusion The monosaccharide composition and conformational features affect their regulatory effects on blood sugar and the gut microbiota.