人参皂苷是人参的主要活性成分，人参及其制品经口服后，天然人参皂苷需经肠道菌代谢后被水解成稀有人参皂苷而发挥其药理作用。由于肠道内定居的微生物菌群受诸多因素影响，个体间肠道菌群多样性和结构组成差异较大。对于肠道内缺少代谢人参皂苷菌群的人群，口服人参后无法达到预期的疗效。因此，肠道菌群多样性与人参皂苷在体内的代谢吸收密切相关。在前期研究中，我们发现大鼠个体间人参皂苷的代谢存在明显差异。在本课题中，我们以人参皂苷代谢具有显著差异的大鼠大肠内容物为研究对象，采用宏基因组学方法研究其肠道微生物多样性、种群结构、功能活性等，探寻并鉴定参与代谢人参皂苷的菌属或菌种，阐明个体间肠道菌群多样性与人参皂苷代谢差异的相关性，揭示不同个体服用人参后的效果差异原因；构建肠道微生物宏基因组文库，筛选、鉴定关键功能基因；筛选代谢人参皂苷的活性菌株，为人参皂苷代谢机制研究提供有价值的线索。

Ginsenosides are the main active components of ginseng. After oral administration of ginseng and its products, naturally occurring ginsenosides will metabolic and hydrolysis into rare ginsenosides by intestinal bacteria to play its pharmacological role. Due to the intestinal microflora settlers affected by many factors, its diversity and structures are quite different. For the populations who are lack of intestinal microflora to metabolize ginseng saponins, they can not reach the corresponding effect after oral administration of ginseng. Thus, intestinal microbial diversity is closely related to absorption and metabolism of ginsenosides in vivo. In the previous study, we found significant differences in the metabolism of ginsenosides in rats. In this study, we use rat colon contents that have significant differences as the research object to explore and identify the bacteria species or genus involved in the metabolism of ginsenosides, and clarify the correlation between individual intestinal flora diversity and metabolic differences of ginsenosides, to reveal the reason of different efficacy of different individuals taking ginseng. Establish intestinal microflora metagenomic library, screen and identify the key of the functional genes. Furthermore, screen the active strains of metabolism of ginsenosides to providing valuable clues for studies on metabolic mechanism of ginsenosides.