Fine-tuning dietary fibre to target gut microbiota accessibility

该项目将探索来自天然基质的益生元纤维的生物可及性及其对人类肠道微生物群的可及性。大多数关于益生元（低聚果糖（FOS）、半乳糖低聚糖（GOS）、阿拉伯木聚糖低聚糖（AXOS））功效的证据都是通过提取和高度精炼的低聚物进行整理的。人们越来越重视最低限度加工的食品，远离高度精制的材料将满足这一需求。这种以天然植物为基础的起始材料的最小加工可以控制组成低聚物的可及性，包括发酵、酶的使用、脉冲电场和热/物理机械预处理等技术以及起始材料的成熟程度。这些过程将改变“母体”多糖的聚合程度和来自天然基质的低聚糖的扩散性——这将微调肠道微生物群对纤维的可及性。该项目将利用人体肠道微生物群模型，结合前沿代谢组学和宏基因组学，研究纤维加工对肠道微生物群组成和微生物可及性的影响。因此，该项目处于物理科学和微生物组科学的交叉点，将对纤维来源进行创新比较，并通过预处理控制纤维来源的程度，以测量纤维来源对肠道发酵的影响，以及对肠道微生物群和代谢标志物的后续影响。

The project will explore the bioaccessibility of prebiotic fibres from natural matrices and their accessibility to the human gut microbiota. Most of the evidence on the efficacy of prebiotics (fructo-oligosaccharides (FOS), galacto-oligosaccharides (GOS), arabinoxylan-oligosaccharides (AXOS)) has been collated using the extracted and highly refined oligomers. There is an increasing emphasis on minimally processed foods and moves away from highly refined materials would meet this need. Such minimal processing of natural plant-based starting materials which control the accessibility of the constituent oligomers might include fermentation, the use of enzymes, technologies such as pulse electric fields and thermo/physico mechanical pre-processing and the degree of ripening of the starting material. These processes will create changes in both the degree of polymerization of the 'parent' polysaccharide and the diffusivity of the oligosaccharides from the natural matrices - which fine-tunes accessibility of the fibre by the gut microbiota. This project will use models of the human gut microbiota combined with cutting-edge metabolomics and metagenomics to study the impact of processing of fibre on gut microbiota composition and microbial accessibility.The project therefore sits at the interface between physical sciences and microbiome science and will an innovative comparison of fibre sources and the extent to which they can be controlled through pre-processing, to measure the effect on in gut fermentation, and subsequent effects on the gut microbiota and metabolic markers.