Abstract:To explore the effects of selenium-enriched green tea extract on mice with intestinal flora dysregulation， ceftriaxone sodium was used to establish the intestinal flora dysregulation model. Changes in the levels of secretory immunoglobulin A（SIgA） and lipopolysaccharide（LPS） in the intestinal tissues， as well as shortchain fatty acids （SCFAs） in mouse feces， were detected. The regulatory effect of selenium-enriched green tea extract on intestinal flora in mice was detected using 16S rRNA high-throughput sequencing. The results showed that selenium-enriched green tea extract significantly increased the SIgA content in the ileum of intestinal flora-dysregulated mice， enhanced SCFAs content in feces， and decreased the LPS content in colon tissue.Compared to ordinary green tea， selenium-enriched green tea extract exhibited stronger intestinal immunomodulatory and anti-inflammatory effects. High-throughput sequencing results showed that selenium-enriched green tea extract could significantly regulate the changes in intestinal microbial diversity induced by ceftriaxone sodium in mice. It inhibited the growth of Proteobacteria and Actinomyces while promoting the proliferation of beneficial bacteria such as Lachnospiraceae， Akkermansia， and Bacteroides. Therefore， selenium-enriched green tea extract could effectively regulate the intestinal microflora of mice.