The study explored the changes of a sulfated polysaccharide (SP) from Gracilaria Lemaneiformis during simulated human digestive system. The results showed SP was scarcely degraded without significant difference. Moreover, the results of fermentation in vitro indicated 53.7% of SP were utilized by gut microbiota with the molecular weight decreasing by 59.41% at 48 h. Meanwhile, 50.07 ± 2.82 mM of short chain fatty acids were produced in culture medium. Besides, in contrast with the regulation of galacto-oligosaccharide sacrificing diversity and richness of community, SP could regulate the composition of microbiota in a mild way. What’s more, Proteobacteria and Firmicutes were the most sensitive phyla responding to changes of pH values in this study. And Sutterella, Phascolarctobacterium, Parabacteroides, Lachnospiraceae_UCG-004, Desulfovibrio and Bacteroides were dominant genera for degrading and utilizing SP. Furthermore, the metagenomic function characteristics of microbes might be changed by SP. Thus, SP could be a potential prebiotic.

该研究探索了在模拟的人的消化系统中，江Gra中硫酸多糖（SP）的变化。结果表明，SP几乎没有降解，没有显着差异。此外，体外发酵结果表明，肠道菌群利用了53.7％的SP，在48 h时分子量降低了59.41％。同时，在培养基中产生了50.07±2.82mM的短链脂肪酸。此外，与调节低聚半乳糖以牺牲群落多样性和丰富性相反，SP可以温和地调节微生物群的组成。此外，在这项研究中，Proteobacteria和Firmicutes是对pH值变化最敏感的门。和Sutterella，Phascolarctobacter，Parabacteroides，Lachnospiraceae_UCG-004，Desulfovibrio和Bacteroides是降解和利用SP的主要属。此外，SP可能会改变微生物的宏基因组功能特征。因此，SP可能是潜在的益生元。