Effects of Persimmon (Diospyros kaki L. cv. Mopan) Polysaccharide and Their Carboxymethylated Derivatives on Lactobacillus Strains Proliferation and Gut Microbiota: A Comparative Study

Persimmon is a fruit that contains sugars, vitamins, phenolic compounds, and various other nutrients. The aim of this study was to explore the structure of carboxymethylated persimmon polysaccharide (CM-PFP) and its interaction with the human gut microbiota. Carboxymethyl modification of the persimmon polysaccharide (PFP) increased both the Mw and Mn, enhanced dispersion stability, and decreased thermal stability. Both PFP and CM-PFP promoted the proliferation of Lactobacillus while inhibiting the proliferation of Staphylococcus aureus and Escherichia coli. In the simulated fecal fermentation, the pH of PFP- and CM-PFP-containing media decreased, the content of short-chain fatty acids increased, and the abundance of intestinal flora at the phylum and genus levels changed. The relative abundance of harmful intestinal bacteria was significantly reduced in both PFP and CM-PFP groups. Furthermore, it was found that CM-PFP was more easily metabolized than PFP, glucose, and fructo-oligosaccharide (FOS) and had a proliferation increase effect on Lactobacillus. Therefore, CM-PFP has a significant positive effect on both Lactobacillus proliferation and the human gut microbiota.