Abstract:This paper investigated the effects of different forms of palmitoleic acid（POA）in regulating intestinal flora of mice with ulcerative colitis（UC）.A UC mouse model was constructed using dextran sulfate sodium salt（DSS）induction.Sixty male BALB/c mice were randomly divided into normal control（NC），model control（MC），positive control（PC，salazosulfapyridine），sea buckthorn pulp oil（SBPO），POA and soy isolate protein-palmitoleic acid（SPI-POA）groups.The anti-inflammatory effect of POA on UC was determined by measuring body weight，disease activity index（DAI），and immune organ indices of thymus and spleen，while its effect on the intestinal flora of UC mice was clarified by 16S rDNA sequencing to study the composition and diversity of microorganisms in the colonic contents.The results showed that compared with the MC group，the administered mice had recovered body weight，reduced DAI score，lowered spleen index（P＜0.01），and increased thymus index（P＜0.01）.Among them，the SPI-POA group had most obvious effect.POA improved the abundance of intestinal flora of UC mice，promoted the proliferation of Muribaculaceae and Lactobacillus and alleviated the dysbiosis caused by inflammation.The effects of the POA group and SPI-POA group tended to be similar to those of the PC group.Therefore，SPI-POA improved UC by regulating the diversity and structure of intestinal flora，and was a potential anti-inflammatory food of plant origin.