为了研究金柚幼果膳食纤维对小鼠肠道健康的影响。将小鼠随机分为6组，按照0.2 mL/10 g体重的剂量进行灌胃。灌胃4周后，HE染色观察结肠组织损伤情况，收集小鼠粪便及结肠，测定水分、pH值和短链脂肪酸（SCFAs）含量。通过试剂盒提取各组小鼠粪便细菌总DNA，利用高通量测序技术对16S rRNA基因的V4区域进行测序，最后通过生物信息学方法对测序数据进行分析，并结合前期研究进行血糖相关指标与肠道菌群的相关性分析。结果显示：金柚幼果膳食纤维实验组可提高糖尿病小鼠在结肠及粪便中的水分含量，SCAFs含量，降低pH值水平，其中水分含量以TDF组上升最为显著，分别提高了8.04%和21.36%；SCAFs含量在结肠、粪便中均在TDF组有显著变化，分别升高475.19%（乙酸）和702.56%（正丁酸）。同时HE染色实验表明金柚幼果膳食纤维在一定程度上可以减缓因糖尿病导致的肠道黏膜损伤；其能够促进有益菌群繁殖，同时抑制有害微生物增殖；该膳食纤维调节小鼠的血糖水平可能与其进入肠道后被益生菌发酵，产生短链脂肪酸有关。结果表明金柚幼果膳食纤维可以维持肠粘膜屏障的完整性，调节肠道菌群的结构，对小鼠的肠道健康具有改善调节的作用。

In order to investigate the effect of dietary fiber from pomelo fruitlets on intestinal health in mice, the mice were randomly divided into 6 groups, in accordance with the dose of 0.2 mL/10 g body weight for intragastric administration. After 4 weeks of gavage, the mouse feces and colon were collected, and the water content, pH value and short-chain fatty acid (SCFAs) content were measured; HE staining was used to observe the damage of colon tissue. The total DNA of the fecal bacteria of each group of mice was extracted by the kit, and the V4 region of the 16S rRNA gene was sequenced using high-throughput sequencing technology. Finally, the sequencing data were analyzed by bioinformatics methods, and the correlation between blood glucose related indicators and intestinal flora was analyzed in combination with previous studies. The results showed that the water content, SCAFs content in the colon and feces of diabetic mice were increased, and the pH level was decreased in the dietary fiber experimental group. The water content in colon and feces of TDF group was increased most significantly, by 8.04% and 21.36%, respectively. SCAFs content in colon and feces were significantly increased in TDF group, increasing by 475.19% (acetic acid) and 702.56% (butyric acid), respectively. Meanwhile, the intestinal mucosal damage caused by diabetes was relieved by the dietary fiber of pomelo fruitlets to some extent in the HE staining experiment Moreover, the growth of beneficial bacteria could be promoted and the proliferation of harmful microorganisms could be inhibited. The blood glucose level of mice was regulated by the dietary fiber, which may be related to the fermentation of probiotics and the production of short-chain fatty acids after entering the intestinal tract. It can be seen that the dietary fiber of pomelo fruitlets can maintain the integrity of intestinal mucosal barrier, regulate the structure of intestinal flora, and improve the intestinal health of mice.

广东省基础与应用基础研究基金项目（2019A1515011283）