ABSTRACT
Objective:To study the effect of Gegen Qinliantang （GQT） on the structure of intestinal flora in dysbacterial diarrhea rats by 16S rRNA sequencing. Method:Sixty healthy SD rats were randomly and equally divided into a control group， a model group， high-， medium-， and low-dose GQT groups， and a Bifidobiogen group. The rat model was induced in the five groups except the control group by administration of mixed antibiotics （178.6 mg·kg<sup>-1</sup> cefradine and 31.25 mg·kg<sup>-1 </sup>gentamicin sulfate） according to the dose. Drug intervention was carried out in each group （7.02， 3.51， and 1.755 g·kg<sup>-1</sup> GQT for the high-， medium-， and low-dose GQT groups， 0.125 g·kg<sup>-1</sup> bifidobacterium capsules for the Bifidobiogen group， and sterile distilled water for the control and model groups） with a volume of 10 mL·kg<sup>-1</sup> for seven days. Colon contents of rats were obtained under anesthesia. The extracted fecal DNA underwent 16S rRNA high-throughput sequencing and the results were analyzed. Result:GQT was proved capable of adjusting the species number and Alpha and Beta diversity， improving the biological richness and diversity of the flora， and positively regulating three differential phyla （Firmicutes， Proteobacteria， and Bacteroidetes） and 14 differential genera （<italic>Bacteroides</italic>，<italic> Parabacteroides</italic>，<italic> Blautia</italic>， etc.） in rat model of dysbacterial diarrhea. Conclusion:The present study confirmed the regulatory effect of GQT on intestinal flora of dysbacterial diarrhea rats， and revealed the physiological and pathological mechanism between intestinal flora and dysbacterial diarrhea.