Accumulating evidence has reported that the gut microbiota could play important roles in the occurrence and progression of colorectal cancer. The nondigestible plant polysaccharides have always been fermented by the intestinal microbiota. Polysaccharides, the predominant functional composition found in jujube fruit, has been shown to inhibit carcinogenesis in animal models. However, the molecular mechanisms involved in polysaccharides preventing carcinogenesis are still uncharacterized. The aim of this study was to investigate the modulatory effects of jujube polysaccharides (JP) on intestinal microbiota, and the influence of JP on the gut flora structure was then analyzed using an AOM/DSS-induced colitis cancer mouse model, using high-throughput sequencing. Contrasted with control group, the addition of JP could ward off colon cancer by ameliorating colitis cancer-induced gut dysbiosis. In addition, there was a significant decrease in Firmicutes/Bacteroidetes post JP treatment. What's more, KEGG pathways of metabolic pathways, ATP-binding cassette (ABC) transporters and two-component system enriched the most differentially expressed genes after JP intervention for 13 weeks. These results suggested that JP showed prebiotic-like activities by positively modulating intestinal microbiota and affecting certain metabolic pathways contributing to host health. In conclusion, our results demonstrated an appreciable capability of JP to restore the gut microbiota profile altered by AOM/DSS, indicating the potential of jujube polysaccharides as promising prebiotic candidates for the prevention and treatment of colorectal cancer.

Two tartary buckwheat samples (Xingku No.2 and Diqing) grown at three locations were analyzed for free and bound phenolic content and antioxidant properties. Moreover, the relative contributions of variety and growing environment to phenolic content and antioxidant properties were determined, as well as correlations of these properties to growing conditions. The total phenolic contents varied from 5,150 to 9,660 μmol of gallic acid equivalents per 100 gram of dry weight (DW) of tartary buckwheat and the free phenolics accounted for 94% to 99%. Rutin content was in the range from 518.54 to 1,447.87 mg per 100 gram of DW of tartary buckwheat. p-Hydroxybenzoic, ferulic and protocatechuic acids were the prominent phenolic acids and other phenolics, including p-coumaric, gallic, caffeic, vanillic and syringic acids were also detected. Tartary buckwheat exhibited higher DPPH^· and ABTS^·+ scavenging activities and was more effective at preventing the bleaching of β-carotene in comparison with reference antioxidant and plant phenolics constituents. Additionally, growing conditions and the interaction between variety and environment may have more contribution than variety to individual phenolics and antioxidant properties of tartary buckwheat. Environmental parameters such as higher altitudes may also have an increasing effect on rutin and phenolic acids. This study suggests that tartary buckwheat has potential health benefits because of its high phenolic content and antioxidant properties. These components could also be enhanced by optimizing the growing conditions of a selected variety.

A novel neutral polysaccharide designated as PAP1b was isolated from Areca catechu L. by hot water extraction, ethanol precipitation, and column chromatography. PAP1b was mainly composed of mannose, galactose, xylose, and arabinose in a ratio of 4.1:3.3:0.9:1.7, with an average molecular weight of 37.3 kDa. Structural characterization indicated that the backbone of PAP1b appeared to be composed mainly of → 6-β-Manp-(1 →, → 4)-α-Galp-(1 → and → 3,6)-β-Manp-(1 →) residues with some branches, and terminal of (1 →)-linked-β-Manp residues. The results of bioactivity experiments showed that PAP1b had antioxidant in vitro, esspecially on scavenging DPPH and hydroxyl radicals. Therefore, the polysaccharide from Areca catechu L. could be used as a potential antioxidant in functional food.