Investigating the fermentation of Porphyra haitanensis linear sulfated heteropolysaccharide by microbial communities using fluorescence labeling

作者：Zhiyun Wang, Dongkun Tu, Sijia Ke, Shiqi Xiao, Juanjuan Guo, Peilin Chen · 发表于：LWT · 年份：2026 · DOI：10.1016/j.lwt.2026.119765 · 研究领域：Seaweed-derived Bioactive Compounds、Algal biology and biofuel production、Polysaccharides Composition and Applications

This study aimed to investigate the effects of Porphyra haitanensis polysaccharide (PHP40) varying in vitro fermentation durations on microbial communities in mouse fecal, alongside conformation changes in PHP under different fermentation periods. In this work, PHP40 was fluorescently labeled with fluorescein isothiocyanate, and its conformation changes during fermentation were characterized using fluorescence spectroscopy and laser confocal microscopy. Structural analysis revealed that PHP40 was composed of galactose and glucose, with a backbone consisting of →3G4Sα(1→4)α-LA(1→4)Gα(1→4)β-Glc(1→, confirming that PHP40 is a linear sulfated heteropolysaccharide. Compared with the Glc group, the relative abundances of Acinetobacter , Staphylococcus , Bacillus and Rhodococcus in the PHP40 group gradually decreased during fermentation, whereas those of Enterococcus and Escherichia-Shigella gradually increased, particularly at 12 h and 24 h of fermentation. Notably, the fluorescence maximum absorption peak of the PHP40_24h group exhibited an obvious red shift compared to the other fermentation time-point groups, accompanied by increased fluorescence intensity. This lays a solid foundation for further studying the kinetics of PHP40 and provides a scientific basis for analyzing bioactive polysaccharides.