脂肪含量偏高的动物食品摄入增多，导致人们血清胆固醇升高而影响健康。乳酸菌因具有减少血清胆固醇的功能而受到了广泛的关注。然而多数研究只是针对单个或有限几个代谢酶或蛋白质进行，研究缺乏系统性。. 本课题以前期从传统乳制品中分离到的一株具有较强的降胆固醇能力且在发酵乳制品和发酵香肠中具有良好应用前景的嗜酸乳杆菌JY2-2为试验菌株，研究该乳杆菌代谢产物和细胞壁组分对高胆固醇膳食模型小鼠肠道菌群的影响和胆固醇降解的机理。利用宏基因组学、差异蛋白质组学、非靶向代谢组学和PCR Array芯片技术，分析不同模型小鼠肠道菌群结构、肝脏脂蛋白、血浆和肝脏中的差异蛋白、差异代谢谱、胆固醇代谢信号通路的相关基因，探索该菌株降胆固醇的活性物质及其调控机制。

The intake of animal food with high fat content increases, which leads to the increase of serum cholesterol and affects people's health. As the lactic acid bacteria with the function to reduce the serum cholesterol level, have been widely concerned. However, most of the studies only aim at single or a few metabolic enzymes or proteins, the existing studies were lack of systematism. . In this study, a Lactobacillus acidophilus JY2-2 isolated from an Inner Mongolia traditional dairy products, which has a good application foreground in Fermented dairy products and fermented sausage processing engineering and has a stronger capability of lowering cholesterol level will be used as target a strain. In order to analyze and explore the mechanism of the strain cell metabolism products and cell wall components lowering cholesterol level and affecting gut microbiota of hypercholesteremic model mice. The study using metagenomics, differential proteomics, untargeted metabolomics and PCR Array chip technology to show the structure of gut microbiota, liver lipoprotein, differential protein in plasma and liver, the related genes of cholesterol metabolism signaling channel different model mouse, in this way the activity of lactic acid bacteria material basis to lowering cholesterol level and adjustment mechanism would be explored.