Abstract：
Dietary fibers have attracted much attention due to their multiple benefits on gut health. In this work, the protective mechanism of dietary fiber from sweetpotato residues (SRDF) on the high-fat diet (HFD)-induced intestinal barrier injury was investigated using microbiome-metabolomics-based approach. The physicochemical property analysis demonstrated a thermal stability below 200 °C and porous pectin-polysaccharide structure of SRDF with high in vitro functional activities. The biochemical analysis indicated that SRDF significantly ameliorated intestinal barrier function by improving intestinal morphology and permeability and inhibiting inflammatory response. Microbiome analysis demonstrated that SRDF significantly reversed the HFD-induced dysbacteriosis, decreased the ratio of Firmicutes/Bacteroides and enhanced the relative abundance of probiotics, such as Muribaculaceae and Bifidobacteriaceae. Metabolomics analysis showed that SRDF also significantly altered the metabolic profile in the colon, wherein the differential metabolites were mainly involved in amino acid metabolism (especially tryptophan). Pearson correlation coefficient identified the beneficial relationship between intestinal microbiome and metabolome induced by SRDF. The limitation of this study was that the mouse model may not fully replicate the human intestinal responses due to the difference between the standard environmental conditions and natural world. Generally, our results implied the great potential of SRDF as a functional food ingredient.
摘要：
膳食纤维因其对肠道健康的多重益处而备受关注。在这项工作中,采用基于微生物组代谢组学的方法研究了甘薯渣膳食纤维（SRDF）对高脂饮食（HFD）诱导的肠屏障损伤的保护机制。理化性质分析表明，SRDF的热稳定性低于200°C，多孔果胶-多糖结构具有较高的体外功能活性。生化分析表明，SRDF通过改善肠道形态和通透性，抑制炎症反应，显著改善肠道屏障功能。微生物组分析表明，SRDF显著逆转了HFD诱导的菌群失调，降低了厚壁菌/拟杆菌的比例，提高了益生菌的相对丰度，如Muribaculaceae和双歧杆菌科。代谢组学分析显示SRDF也显著改变了结肠的代谢谱,其中差异代谢产物主要参与氨基酸代谢（尤其是色氨酸）。Pearson相关系数确定了由SRDF诱导的肠道微生物组和代谢组之间的有益关系。这项研究的局限性在于，由于标准环境条件和自然界之间的差异，小鼠模型可能无法完全复制人类肠道反应。一般来说,我们的研究结果暗示了SRDF作为功能性食品成分的巨大潜力.
