研究不同剂量当归超微粉对小鼠肠道菌群多样性、肠道生理结构的作用。将C57BL/6小鼠分为当归超微粉高剂量组（2.0 g/kg）、中剂量组（1.0 g/kg）、低剂量组（0.5 g/kg）、传统饮片组（2.0 g/kg）、传统粉末组（2.0 g/kg）和空白组，灌胃给药15 d，记录体重，在灌喂第15 d时无菌取结肠内容物，扩增肠道菌群16S rRNA基因的V3+V4区，采用高通量测序分析β多样性和α多样性、分析门水平和属水平的物种组成，HE染色法观察胃肠道病理变化。结果显示，C57BL/6小鼠体重正常生长，当归超微粉饮片高剂量组的对小鼠肠道微生物的疣微菌门（Verrucomicrobia）含量显著增加（p<0.05），放线菌门（Actinobacteria）含量减少（p<0.01）。另外，当归超微粉饮片中剂量组拟杆菌门（Bacteroidetes）含量降低最为显著，厚壁菌门（Firmicutes）增加最为显著；在属水平中剂量Faecalibaculum增加最明显（p<0.05），故超微粉的中剂量为最佳实验剂量。各处理组小鼠胃肠道无病理变化。本实验可为当归以超微粉的使用方式，对人体保健或治疗使用的科学用量和安全性，提供理论依据。另外，可为以肠道菌群相关的有效性提供技术支持。

The effects of different doses of ultrafine powder on the diversity of intestinal flora and physiological structure of the intestinal tract in mice were studied. C57BL/6 mice were divided into high-dose ultrafine powder group (2.0 g/kg), medium-dose group (1.0 g/kg), low-dose group (0.5 g/kg) and traditional decoction piece group (2.0 g/kg), the traditional powder group (2.0 g/kg) and the blank group, and subject to intragastric administration for 15 days. The body weights were recorded. On the 15th day of gavage, the colon contents were taken out aseptically, the V3+V4 region of the 16s rRNA gene of the intestinal flora was amplified, and the beta diversity and alpha diversity were analyzed by high-throughput sequencing. The compositions of the species at the phylum level and genus level were analyzed, and the pathological changes of the gastrointestinal tract was examined by HE staining. The results showed that the body weight of C57BL/6 mice grew normally. The high-dose of Angelica sinensis ultrafine powder decoction pieces significantly increased the content of Verrucomicrobia (p<0.05) and decreased the content of Actinobacteria (p<0.01). In addition, in the medium-dose group of Angelica sinensis ultrafine powder decoction pieces, the content of Bacteroidetes decreased the most with the most significant increase of Firmicutes. At the genus level, the medium-dose increased the most significantly the content of Faecalibaculum (p<0.05). Therefore, the medium dose of ultrafine powder was the most suitable experimental dose. There was no pathological change in the gastrointestinal tract of mice in each treatment group. This experiment can provide a theoretical basis for the scientific dosage and safety of Angelica sinensis ultrafine powder for human health care or treatment, and offer technical support for the effectiveness of the intestinal flora.

吉林省科技发展计划项目（20190201153JC）