Li Jiayi, Lv Youjing, Shao Meng, Lv Depeng, Fu Zhiliang, Guo Peng, Li Quancai, Shang Qingsen
Key Laboratory of Marine Drugs of Ministry of Education, Shandong Key Laboratory of Glycoscience and Glycotherapeutics, School of Medicine and Pharmacy, Ocean University of China, Qingdao 266003, China.
Laboratory for Marine Drugs and Bioproducts, Qingdao Marine Science and Technology Center, Qingdao 266237, China.
Nutrients. 2025 Apr 24;17(9):1424. doi: 10.3390/nu17091424.
Alginate and its oligosaccharides (AOS) are widely used in the food industry all over the world. However, how they are fermented by the human gut microbiota has not been fully elucidated. Here, we aim to explore the structure-property relationships of the fermentation of these carbohydrates by the human gut microbiota. High-performance liquid chromatography, 16S rRNA gene amplicon high-throughput sequencing, whole genome sequencing, and metabolome analysis were used to study the fermentation of alginate and AOS by the human gut microbiota. Low-molecular-weight alginate and AOS were more fermentable than alginate. Moreover, fermentation of AOS with a molecular weight (Mw) of 0.8 kDa produced higher amounts of acetate and butyrate than that with a Mw of 0.3 kDa. was a keystone species responsible for the fermentation. Additionally, each strain was characterized with a unique capability for AOS fermentation. Specifically, P19-10, a bacterium isolated from healthy human colon, exhibited the best fermentation capacity. Genomic analysis suggested that P19-10 was armed with a plethora of carbohydrate-active enzymes. Additionally, the polysaccharide lyase family 6_1 was identified as a candidate enzyme responsible for the utilization of AOS. Moreover, fermentation of AOS by P19-10 was associated with significant changes in bacterial metabolites and metabolic pathways. Our study provides novel mechanistic insights into the fermentation of alginate and AOS by human gut microbiota, which has applications for the development of new carbohydrate-based nutraceuticals and foods.
藻酸盐及其寡糖（AOS）在全球食品工业中广泛应用。然而，它们如何被人体肠道微生物群发酵尚未完全阐明。在此，我们旨在探索这些碳水化合物被人体肠道微生物群发酵的结构-性质关系。使用高效液相色谱、16S rRNA基因扩增子高通量测序、全基因组测序和代谢组分析来研究人体肠道微生物群对藻酸盐和AOS的发酵。低分子量藻酸盐和AOS比藻酸盐更易发酵。此外，分子量（Mw）为0.8 kDa的AOS发酵产生的乙酸盐和丁酸盐比Mw为0.3 kDa的AOS更多。 是负责发酵的关键物种。此外，每个 菌株都具有独特的AOS发酵能力。具体而言，从健康人结肠分离出的细菌P19-10表现出最佳发酵能力。基因组分析表明，P19-10拥有大量碳水化合物活性酶。此外，多糖裂解酶家族6_1被鉴定为负责利用AOS的候选酶。此外，P19-10对AOS的发酵与细菌代谢物和代谢途径的显著变化有关。我们的研究为人体肠道微生物群对藻酸盐和AOS的发酵提供了新的机制见解，这对开发新的基于碳水化合物的营养保健品和食品具有应用价值。
