【摘要】 为探究褐藻胶寡糖（Alginate oligosaccharides,AOS）在肠道环境中对沙门氏菌的影响，使用酶解法获得AOS，评价AOS的体外模拟消化特征，利用体外模拟发酵模型对鸡肠道菌群发酵AOS过程中的细菌总数和沙门氏菌总数定量，并利用转录组学分析沙门氏菌在肠道环境中对AOS的响应。结果表明，在模拟胃肠液中，AOS还原糖含量和分子质量都没有明显变化，AOS不易被消化。当AOS被肠道细菌发酵时，菌群中沙门氏菌的相对丰度从4.6%降到1.1%。转录组学和实时荧光定量PCR分析表明，沙门氏菌鞭毛组装、双组分系统、侵染、毒力关键基因的表达量下调。可见，AOS的肠道菌群代谢产物可以抑制沙门氏菌的生长和毒性。更多还原

【Abstract】 In order to explore the effect of alginate oligosaccharides(AOS)on S. enterica in the intestinal environment,AOS was prepared by enzymatic degradation,furthermore the simulated digestion characteristics of AOS were evaluated in vitro. The total number of bacteria and S. enterica in the process of AOS fermentation by chicken gut microbiota were quantified by in vitro simulated fermentation model,and the response of S. enterica to AOS in the intestinal environment was analyzed by transcriptomics. The results showed that the content of reducing sugar and molecular weight of AOS did not change significantly,indicating that AOS were not digested. When AOS was fermented by gut microbiota,the relative abundance of S. enterica in the flora decreased from 4. 6% to 1. 1%. Transcriptomics and reverse transcription-quantitative PCR analysis showed that the expression of key genes of S. enterica flagella assembly,two-component system,infection and virulence was down-regulated. Therefore,the gut microbiota metabolites of AOS could inhibit the growth and virulence of S. enterica.更多还原