College of Food Science and Technology, Yunnan Agricultural University, Kunming 650201, China; Institute of Agro-Food Science and Technology, Shandong Academy of Agricultural Sciences, Jinan 250100, China.
Institute of Agro-Food Science and Technology, Shandong Academy of Agricultural Sciences, Jinan 250100, China.
Int J Biol Macromol. 2024 Nov;279(Pt 4):135568. doi: 10.1016/j.ijbiomac.2024.135568. Epub 2024 Sep 11.
This study investigated the physicochemical properties, digestive stability, and in vitro fermentation behavior of Polygonatum kingianum polysaccharide (PKP) fractions (PKP60, PKP70, PKP80) obtained through graded ethanol precipitation. High-performance gel permeation chromatography revealed significant molecular weight differences among the fractions, while reverse-phase high-performance liquid chromatography indicated consistent monosaccharide types with variations in their proportions. Uronic acid analysis confirmed that all polysaccharide fractions met the criteria for neutral polysaccharides. Congo red staining confirmed the presence of a triple-helix structure in all PKP fractions. Comprehensive analysis demonstrated that these fractions remained stable during in vitro digestion, as evidenced by consistent molecular weights and total carbohydrate content, with no significant production of free monosaccharides or reducing sugars. All PKP fractions were fermented by gut microbiota, resulting in the production of short-chain fatty acids. Beta diversity and structural analyses of gut microbiota revealed distinct modulatory effects associated with each PKP fraction. The PKP fractions promoted probiotic growth, especially PKP70, which significantly enhanced Bifidobacterium proliferation, indicating strong prebiotic potential. These findings underscore the importance of isolation and purification methods in determining the functionality and gut microbiota-modulating effects of plant-derived polysaccharides, emphasizing the need for in-depth research that extends beyond merely evaluating their source.
本研究通过分级乙醇沉淀法获得玉竹多糖（PKP）的分级醇沉部分（PKP60、PKP70、PKP80），并对其理化性质、消化稳定性和体外发酵行为进行了研究。高效凝胶渗透色谱法显示各部分的分子量存在显著差异，而反相高效液相色谱法则表明存在一致的单糖类型，但比例有所不同。糖醛酸分析证实所有多糖部分均符合中性多糖的标准。刚果红染色证实所有 PKP 部分均存在三螺旋结构。综合分析表明，这些部分在体外消化过程中保持稳定，分子量和总碳水化合物含量一致，没有游离单糖或还原糖的显著产生。肠道微生物群发酵所有 PKP 部分，产生短链脂肪酸。肠道微生物群的 beta 多样性和结构分析揭示了与每个 PKP 部分相关的独特调节作用。PKP 部分促进了益生菌的生长，特别是 PKP70，它显著促进了双歧杆菌的增殖，表明其具有很强的益生元潜力。这些发现强调了分离和纯化方法在确定植物来源多糖的功能和肠道微生物群调节作用方面的重要性，强调需要进行深入研究，而不仅仅是评估其来源。
